RAPID ENVIRONMENTAL IMPACT ASSESSMENT

Transcription

1 RAPID ENVIRONMENTAL IMPACT ASSESSMENT FOR THE PROPOSED AUGMENTATION & EXPANSION OF EXISTING THERMAL POWER PLANT BY M/s. ARS Metals Pvt. Ltd. Chennai, Tamil Nadu AT Sithurnatham, Sirupuzhalpettai & Eguvarapalayam villages, Gummidipoondi taluk, Thiruvallur district, Tamil Nadu Project Proponent M/s. ARS Metals Pvt. Ltd. Chennai, Tamil Nadu EIA Consultant M/s. Vimta Labs Limited Hyderabad / Coimbatore QCI/NABET Accredited EIA Consultant FINAL EIA REPORT JULY 2015

2 PREFACE ARS METALS PVT. LTD. Chennai, Tamil Nadu, India RAPID ENVIRONMENTAL IMPACT ASSESSMENT FOR THE PROPOSED AUGMENTATION & EXPANSION OF EXISTING THERMAL POWER PLANT AT SITHURNATHAM, SIRUPUZHALPETTAI & EGUVARAPALAYAM VILLAGES, GUMMIDIPOONDI TALUK, THIRUVALLUR DISTRICT, TAMIL NADU For and on behalf of VIMTA LABS LIMITED Approved by : K. S. Muneeswaran Signed : Designation : Senior Manager Date : This EIA report has been prepared for the purpose of obtaining Environmental Clearance from MoEF-CC, New Delhi in line with the ToR issued by MoEF-CC vide letter no. F. No. J-13012/7/2010-IA.II (T) dt This report has been prepared by Vimta Labs Limited with all reasonable skill, care and diligence within the terms of the contract with the client, incorporating our General Terms and Conditions of Business and taking account of the resources devoted to it by agreement with the client.

3 district, Tamilnadu Table of contents TABLE OF CONTENTS Chapter # Title Page # Preface Table of Contents List of Annexures List of Figures List of Tables i iii viii ix x 1.0 Introduction Purpose of the report Identification of the project & project proponent Brief description of the project Project objective Nature and size of the project Location of the project Scope of the study Study area for EIA Methodology of the study Project description Type of Project Need for the project Project location & layout Size or magnitude of operation Land requirement Fuel requirement, source, quality &transportation Power evacuation Man power requirement Water requirement Infrastructure Infrastructure for labour Project schedule for implementation Technology and process description Plant layout Mechanical equipment and systems Plant water system Coal handling system Ash handling system Miscellaneous auxiliaries Cranes, hoists & elevators Associated facilities General stores 52 VIMTA Labs Limited, Hyderabad/Coimbatore iii

4 district, Tamilnadu Table of contents TABLE OF CONTENTS (Contd..) Chapter # Title Page # 2.11 Sources of pollution and mitigation measures Air pollution source and mitigation measures Wastewater generation and mitigation measures Solid waste generation and mitigation measures Noise pollution and mitigation measures Environmental laboratory Description of the environment Introduction Methodology Geology & hydrogeology Administrative details Basin and sub-basin Drainage Rainfall and climate Geomorphology and soil types Soil Ground water scenario Land use studies Objectives Methodology Land use pattern based on satellite imagery Meteorology Methodology Synthesis of data on climatic conditions Air quality Methodology adopted for air quality survey Instruments used for sampling Instruments used for analysis Sampling and analytical techniques Presentation of primary data Observations of primary data Noise level survey Identification of sampling locations Method of monitoring Instrument used for monitoring Parameters measured during monitoring Presentation of results Soil characteristics Data generation Baseline soil status Water quality Methodology Water sampling locations Presentation of results 98 VIMTA Labs Limited, Hyderabad/Coimbatore iv

5 district, Tamilnadu Table of contents TABLE OF CONTENTS (Contd..) Chapter # Title Page # 3.10 Ecology and biodiversity Introduction Objectives of the study Methodology General ecology of the study area Forest blocks Terrestrial biodiversity Fauna of the core zone Flora of the buffer zone Fauna of the buffer zone Aquatic ecosystems Conclusions Demography and socio-economics Methodology adopted for the study Review of demographic and socio-economic Demography Social structure Literacy levels Occupational structure Anticipated environmental impacts & mitigation measures Introduction Impacts during construction phase Impact on land use Impact on soil Impact on topography Impact on air quality Impact on water quality Impact on noise levels Impact on terrestrial ecology Impacts during operational phase Topography Impact on air quality point sources Impact on air quality - fugitive emissions Impact on water resources and water quality Impact on land use Impact on soil Impact of solid wastes Impacts on ecology Impacts on noise levels Predictions of impacts on socio economics Impacts on public health and safety 134 VIMTA Labs Limited, Hyderabad/Coimbatore v

6 district, Tamilnadu Table of contents TABLE OF CONTENTS (Contd..) Chapter # Title Page # 4.4 Environment management plan during erection phase Land environment management Air quality management Water quality management Noise level management Ecological management Environment management plan during operation phase Air pollution management Water pollution management Rainwater harvesting system Noise pollution management Solid waste management Greenbelt development Species for plantation Cost provision for environmental measures Corporate social responsibility Analysis of Alternatives Analysis of alternative sites for location of power plant Analysis of Alternative for Unit Size Selection Environmental monitoring programme Introduction Implementation schedule of EMP Environmental monitoring and reporting procedure Monitoring schedule Monitoring methods and data analysis of 152 environmental monitoring 6.6 Report schedules of the monitoring data Infrastructure for monitoring of environmental 154 protection measures 7.0 Additional studies Public consultation Risk assessment Hazard identification Hazard assessment and evaluation Disaster management plan Off-site Emergency Preparedness Plan Occupational Health and Safety 183 VIMTA Labs Limited, Hyderabad/Coimbatore vi

7 district, Tamilnadu Table of contents 7.8 Public Consultation 187 TABLE OF CONTENTS (Contd..) Chapter # Title Page # 8.0 Project benefits Introduction Availability of Quality Power Improvements in the Physical Infrastructure Improvement in the Social Infrastructure Employment Potential Administrative aspects of environment management plan Institutional Arrangements for Environment 191 Protection and Conservation 10.0 Summary & conclusion Identification of project and project proponent Details of the proposed project Baseline environmental status Anticipated environmental impacts Environmental management plan Post Project Environment Monitoring Programme Risk Assessment and Disaster Management Plan Project benefits Conclusion Disclosure of consultant Introduction The quality policy Milestones and accreditations Management and board of directors Services offered Services Facilities Quality systems Achievements 213 QCI/NABET accreditation certificate of consultant 214 VIMTA Labs Limited, Hyderabad/Coimbatore vii

8 district, Tamilnadu Table of contents LIST OF ANNEXURES Annexure # Title Annexure 1 Annexure 2 Annexure 3 Annexure 4 Annexure 5 Annexure 6 Annexure 7 Annexure 8 Annexure 9 Annexure 10 Annexure 11 Annexure 12 Annexure 13 Annexure 14 Annexure 15 Annexure 16 Annexure 17 Annexure 18 Annexure 18B Annexure 19 Annexure 20 Annexure 21 TORs issued by MoEF Compliance report for ToR issued by MoEF EC & CTO for the Existing Plant MoEF certified EC compliance Administrative setupmaps Applicable Environmental Standards Methodology adopted for sampling and analysis Study area map Ambient Air Quality Results of study area Demographic details of the study area Land use details of the study area Drainage pattern & water bodies Plant & site photos CGWA Letter for Ground water uptake letter Lab Report On Coal Characteristics MoEF Questionnaires for Environmental Appraisal of Thermal Power Plant Public Hearing - Advertisement copy English Executive Summary Tamil Executive Summary Public Hearing - Minutes of the Meeting MoU for coal supply Agreement for selling Fly ash VIMTA Labs Limited, Hyderabad/Coimbatore viii

9 district, Tamilnadu Table of contents LIST OF FIGURES Figure# Title Page# 1.1 Index map of the plant site km study area map Topographic map Aerial view of the plant site Plant layout Water balance (upon expansion) Power generation flow scheme Hydrogeology of Thiruvallur district Flow chart showing methodology of land use mapping Satellite imagery of the study area Landuse of the study area (A) Windrose for pre monsoon & monsoon season- IMD, Chennai (B) Windrose for post monsoon & winter season IMD, Chennai (C) Annual wind rose - IMD, Chennai Site specific wind rose (May July 2014) Air quality sampling locations Noise monitoring locations Soil sampling locations Water sampling locations Ecological sampling locations Short term 24 hourly incremental GLCs of PM Short term 24 hourly incremental GLCs of SO Short term 24 hourly incremental GLCs of NO X Predicted noise dispersion contours Damage Contour For Two LDO Tanks (150 Kl Each) On Fire Damage Contour For Two HFO Tanks (300 Kl Each) On Fire On-Site Emergency Organization Chart Public Hearing Photos Organizational structure of environment cell Km Radius Study Area Of The Project Site 194 VIMTA Labs Limited, Hyderabad/Coimbatore ix

10 district, Tamilnadu Table of contents LIST OF TABLES Table# Title Page# 1.1 Project brief Environmental setting of the plant Environmental attributes and frequency of monitoring Demand projections Salient features of thermal power plant Land break-up Coal consumption Indonesian coal characteristics Man power demand Water demand Steam generator specifications Turbine specifications Sources of wastewater and its management Details of coal handling system Stack monitoring data Wastewater generation from the power plant Solid waste generation and disposal Noise level exposure limits Ground water resources Sensitivity of meteorology monitoring equipment Climatological data-imd, Chennai Seasonal frequencies of cyclones in east coast of India Summary of wind pattern IMD, Chennai Summary of the meteorological data at site Details of ambient air quality monitoring locations Monitored parameters and frequency of sampling Instruments used for analysis of samples Techniques used for ambient air quality monitoring Summary of ambient air quality results Details of noise monitoring locations Noise levels in the study area Analytical techniques for soil analysis Details of soil sampling locations Soil analysis results Standard soil classification Details of water sampling locations Ground water quality Surface water quality List of ecological sampling locations List of forest blocks within 10 Km radius List of flora in the core area List of fauna in the core area List of flora from the buffer zone 107 VIMTA Labs Limited, Hyderabad/Coimbatore x

11 district, Tamilnadu Table of contents 3.26 List of fauna from the buffer zone List of plankton recorded during study period Aquatic fauna from study area Distribution of population Distribution of population by social structure Distribution of literate and literacy rate Occupational structure Hourly mean meteorological data Stack details Predicted 24-hourly incremental concentrations Resultant concentrations due to incremental GLC s Types of wastewater generation and treatment details Expected quality of wastewater Expected solid waste from power plant Major noise generating sources Selected areas of fly ash utilization Cost provision for environmental measures (a)Expenses towards CSR (b)Expenses towards CSR EMP implementation schedule Environmental monitoring schedule during construction stage Environmental monitoring schedule during operation phase Hazardous materials proposed to be stored/transported Category wise schedule of storage tanks Properties of fuels used in the plant Applicability of GOI rules to fuel/chemical storage Preliminary hazard analysis for storage areas Preliminary hazard analysis for the whole plant in general Fire explosion and toxicity index Fire explosion and toxicity index Damage due to the incident radiation intensities Radiation exposure and lethality Scenarios considered for MCA Analysis Properties of fuels considered for modeling Occurrence of various intensities Pool fire Hazard analysis for process in power plant Hazardous events contributing to risk at on-site facility Off-site action plan Environmental setting of the plant Salient Features of the Proposed Project Summary of Ambient Air Quality in the Study Area Resultant Concentrations Due to Incremental GLCs Expected Solid Waste from Power Plant 202 Details of Personnel Involved In Current EIA Report 214 VIMTA Labs Limited, Hyderabad/Coimbatore xi

12 1.0 INTRODUCTION Rapid Environmental Impact Assessment for the proposed augmentation & district, Tamilnadu Chapter 1 Introduction M/s. ARS Metals Private Limited (hereinafter referred to as ARS) proposes for an augmentation & expansion of its existing thermal power plant (TPP) at Sithurnatham, Sirupuzhalpettai & Eguvarapalayam villages of Gummidipoondi taluk, Thiruvallur district, Tamil Nadu. The existing plant operates in a total plant area of ha (62.99 acres) for which EC has been obtained vide Letter No. J /7/2010-IA.II (T) dated 20 th May, 2011 for 2 x 60 MW. Of this, only 1 x 60 MW is under operation since commencing the power plant. The proposed expansion activity involves augmentation of the other 60 MW to 135 MW and erection of additional 350 MW Super Critical TPP. For the current expansion, additional ha (28.39 acres) of land, adjacent (NE) to existing plant site has been acquired. Altogether, the plant after expansion will be operated in ha (91.38 acres). The total cost for the proposed expansion will be INR 2,400/- Crores. The purpose of proposed expansion is to meet its group captive requirement and the excess power will be sold to Tamil Nadu state grid. This chapter describes the purpose of the report, identification of the current expansion activity and the project proponent, brief description of nature, size and location of the project and importance to the region and country. This chapter also describes the scope of the study and details of regulatory scoping carried out as per Terms of Reference (ToR) issued by Ministry of Environment and Forests (MoEF), New Delhi. 1.1 Purpose of the report In order to obtain Environmental Clearance from MoEF and Consent for Establishment (CFE) from the Tamilnadu Pollution Control Board (TNPCB) for the current expansion activities, Environmental Impact Assessment (EIA) report with detailed Environmental Management Plan (EMP) is essential as per the EIA notification and its subsequent amendments. As per the EIA Notification dated 14 th September 2006, the proposed activity falls under schedule. no. 1 (d) [Thermal Power Plant > 500 MW] and categorized under category A. The project was presented in the 18 th meeting of the reconstituted expert appraisal committee (EAC) MoEF [Thermal Power] held on 1 st August 2014 for ToR approval and received ToR vide letter no. F. No. J-13012/7/2010-IA.II (T) dt (Annexure 1). The objective of this REIA is to foresee the potential environmental problems that would crop up out of the proposed expansion activity and address them in the project planning and design stage. VIMTA Labs Limited, Hyderabad/Coimbatore 1

13 district, Tamilnadu Chapter 1 Introduction The specific objectives of this REIA are as follows: To review the current environmental status of the plant under operation, and its surrounding area, to estimate the pollution that would occur after commissioning the proposed expansion activity, and its impact on the surrounding environment. To suggest an EMP including pollution control methods, to ensure that the pollution will be well within the limits as prescribed by CPCB and TNPCB and minimize the adverse environmental impacts of the development, so that the quality of environment is not only preserved but also enhanced. To propose a Post Project Monitoring Plan (PPMP) to ensure that the EMP achieves its desired objectives. 1.2 Identification of Project & Project Proponent The proposed augmentation / expansion of the existing thermal power plant is identified and justified based on the growing demand of power requirement. India's Electricity Act 2003 introduced structural changes to the power industry, permitting private investment for the first time since This allowed power producers to sell power directly to industrial consumers under the Group Captive model. ARS has been a pioneer in developing the Group Captive model which allows the flexibility to choose between two market routes. ARS Metals Pvt. Ltd. ARS is a pioneer in the field of manufacturing TMT re-bars (Thermo Mechanically Treated) and Mild Steel Billets. ARS metals being one of the largest integrated steel plants in Southern India, has acquired high reverence from its loyal customers throughout South India. ARS has a unique distribution network in South India. The company has made it easy for the customers to procure their requirements such as high quality TMT rebars and mild steel billets at their location through authorized distributors at various places in the South India. Company Highlights One of the largest integrated Steel Plants in Southern India. Fully modern & automated plant for best quality TMT re-bars and Mild Steel Billets. Excellent distribution Network spread across entire Southern India. Sophisticated infrastructure facilities for R&D. Stringent Quality Control standards to ensure the best quality TMT re-bars and Mild Steel Billets. VIMTA Labs Limited, Hyderabad/Coimbatore 2

14 district, Tamilnadu Chapter 1 Introduction 1.3 Brief Description of the Project Project Objective The proposed expansion involves augmentation of 60 MW to 135 MW Group Captive Power Plant (GCPP) and erection of additional 350 MW Independent Power Plant (IPP) in addition to the existing 1 x 60 MW (GCPP) under operation Nature and Size of the Project The existing plant operates in a total plant area of ha (62.99 acres) for which EC has been obtained vide Letter No. J-13012/7/2010-IA.II (T) dated 20 th May, 2011 for 2 x 60 MW. Of this, only 1 x 60 MW is under operation since commencing the power plant. The proposed expansion activity involves augmentation of the other 60 MW to 135 MW and erection of additional 350 MW TPP. For the current expansion, additional ha (28.39 acres) of land, adjacent (NE) to existing plant site has been acquired. Altogether, the plant after expansion will be operated in ha (91.38 acres). The total cost for the proposed expansion will be INR 2,400/- Crores. The details of the project are given in Table-1.1. TABLE 1.1 PROJECT BRIEF Sr. No. Description Details 1 Name of the project Augmentation & expansion of existing thermal power plant 2 Registered address of the Rajesh Bhatia proponent Director M/s. ARS Metals Private Limited D-109, 2 nd Floor, LBR complex, Anna Nagar (East), Chennai Telephone numbers Ph. No Location of the plant site Sithurnatham, Sirupuzhalpettai & Eguvarpalayam villages, Gummidipoondi taluk & Thiruvallur district, Tamil Nadu 5 Power generation capacity Status Existing (as per EC) Upon expansion Total Capacity 2 x 60 MW (120 MW) 1 x 60 MW 1 x 135 MW 1 x 350 MW [Super critical] 545 MW _ 6 Power requirement The entire power demand will be met from the existing & proposed captive power plant 7 Fuel requirement Fuel Existing After expansion Coal (TPD) 1000 (0.3 MTPA) 7712 (2.31 MTPA) VIMTA Labs Limited, Hyderabad/Coimbatore 3

15 district, Tamilnadu Chapter 1 Introduction 8 Water Requirement Total water demand: 240 KLD Fresh water requirement: KLD Source: Existing bore wells 9 Details of Land use/land Cover within plant site Total plant area after expansion ha (91.38 acres) Sr. No. Description Area ha acres % 1 Boiler house Turbine generator hall Air cooled condenser Water treatment plant ESP and stack Switch yard Coal storage yard Greenbelt Raw water reservoir Road Ash dyke Open area Total _ 10 Total investment of the project/activity The total cost for the proposed expansion is INR 2400/- Crores 11 Funds allocated for EMP Capital cost: INR. 360 Crores Recurring cost: INR. 26 Crores/annum 12 Estimated Employment Present employees 150 nos. Additional employees 200 nos. 13 Name of the Environment Consultant involved in EIA report preparation M/s. VIMTA LABS LIMITED S. No. in QCI list: #159 Branch office: No. 8 Azad Road R. S. Puram, Coimbatore Regd. office: 142, IDA, Phase-II, Cherlapally, Hyderabad QCI/NABET Accredited EIA Consultancy Organization, NABL Accredited, ISO Certified and MoEF Recognized Laboratory VIMTA Labs Limited, Hyderabad/Coimbatore 4

16 district, Tamilnadu Chapter 1 Introduction Location of the Project The plant site falls within »» North latitude and and longitude. The entire plant area falls in the Survey of India topo sheet nos. 57 O/15, 66 C/2 & 66 C/3. Existing plant site is 4.8 km, West of National Highway 5. The nearest railway station is Gummidipoondi R.S., which is at a distance of about 6.1 km, ESE. The nearest airport is Anna International Airport, Chennai which is located at a distance of 48.3 km, SSE from plant site. The project site falls in Sithurnatham, Sirupuzhalpettai & Eguvarpalayam villages, Gummidipoondi taluk, Thiruvallur district, Tamilnadu. List of S.F. Nos. covered under the project area are given below. Existing land area: ha (62.99 acres) 52/3 52/4 207/1 pt 206/2 44/2 207/13 209/7 651/1 611/1G 52/6 52/2 207/10 207/2 44/3 207/14 209/8 651/2 611/1I 52/7 52/8 207/11 207/4 50/3A 207/17 53/4 651/3 52/9 52/1B 207/12 46/2 51/12 207/18 53/6 651/4 53/12 49/3 207/16 49/8 51/3 207/15 53/10 611/1A 53/13 49/5 45/4 50/2C 51/6 207/19 53/11 611/1B 50/4 50/5C 49/1 50/2E 52/1A 209/1 53/7 611/1C 50/5B 50/2B 49/2 50/2A 207/3 209/2 53/5 611/1D 50/6B 50/2D 49/4 50/3C 207/5 209/3 53/8 611/1F 52/5 50/5D 49/6 50/3D 207/7 209/4 53/9 611/1H 45/3 50/6A 49/7 50/3E 207/8 209/5 611/1K 611/1J 46/1 50/5A 207/1 pt 50/3B 207/9 209/ /1E Proposed additional land area : ha (28.39 acres) 210/1L 210/1K 63/12 A 210/1H 119/18C 119/6F 131/14 210/1A 210/1M 609/1 210/1I 131/17 131/11A 129/9B 609/3 210/2 609/6A 210/1J 107/7 126/7 129/1 610/2C 609/5C 612/1A 126/2C 126/6A 126/2A 129/2 63/3 609/2 63/11 117/8B 117/8C 126/2B 129/10A 210/1B 609/4 63/3 120/15B 120/14 131/20 129/11 210/1C 609/6B 63/5A 131/9 131/7 131/15 29/10B 210/1D 610/2B 63/5B 134/5C 131/10C 128/5 129/1 210/1F 610/1A 210/1B 128/3 128/4 120/5 210/1G 609/5A 210/1E 125/2C 125/2B 118/8A The environmental setting of the plant is given in Table-1.2. The location map of the project site is shown in Figure-1.1 and the topographic map (5.0 km) showing site co-ordinates is shown is Figure-1.3. Aerial view of the project site showing the existing plant site and the proposed area allotted for the erection of 350 MW (IPP) is shown in Figure-1.4. VIMTA Labs Limited, Hyderabad/Coimbatore 5

17 district, Tamilnadu Chapter 1 Introduction EXISTING PLANT SITE FIGURE 1.1 INDEX MAP OF THE PLANT SITE VIMTA Labs Limited, Hyderabad/Coimbatore 6

18 district, Tamilnadu Chapter 1 Introduction FIGURE KM STUDY AREA MAP VIMTA Labs Limited, Hyderabad/Coimbatore 7

19 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 1 Introduction ARS Metals Private Limited TOPO Map showing the project site and its co-ordinates FIGURE 1.3 TOPOGRAPHIC MAP VIMTA Labs Limited, Hyderabad/Coimbatore 8

20 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 1 Introduction EXISTING PLANT AREA FOR PROPOSED EXPANSION EXISTING PLANT FIGURE 1.4 AERIAL VIEW OF THE PLANT SITE VIMTA Labs Limited, Hyderabad/Coimbatore POWER PLANT 9

21 WIND ROSE PLOT: COMMENTS: WRPLOT View - Lakes Environmental Software DATA PERIOD: CALM WINDS: AVG. WIND SPEED: COMPANY NAME: MODELER: TOTAL COUNT: DATE: DISPLAY: PROJECT NO.: >= Calms: 3.34% Rapid Environmental Impact Assessment for the proposed augmentation & District, Tamilnadu Chapter 1 Introduction TABLE 1.2 ENVIRONMENTAL SETTING OF THE PLANT Sr. No. Particulars Details NORTH 20% 16% 12% 8% 4% WEST EAST WIND SPEED (m/s) 1 Site-coordinates Refer Figure Elevation 18.0 m AMSL 3 Climatic conditions (IMD, a. Annual Max. Temp: C Chennai) b. Annual Min. Temp: C c. Annual Total Rainfall: mm d. Predominant Wind Direction: Pre-monsoon: S, SSW Monsoon: SSW, SW, S Post monsoon: NNE, E, N, NE Winter: NE, S, NNE, E Annual: SSW, S, SW 4 Station # 03 Wind Speed Direction (blowing from) Climatic conditions (Plant site) 1 st May to 31 st July 2014 a. Max. Temp: C b. Min. Temp: C c. Rainfall: mm d. Predominant Wind Direction: First pre-dominant: West 18.49% Second pre-dominant: South 14.56% Third pre-dominant: WSW 11.94% Calm: 3.34% SOUTH 5 Start Date: 1/1/ :00 Land use End Date: 1/30/ :00 Industrial 6 Nearest highway NH km, East % 719 hrs. Nearest railway station 3.57 m/s 8/25/2014 Gummidipoondi R.S. 6.1 km, ESE 8 Nearest airport Anna International Airport, Chennai 48.3km, SSE 9 Nearest habitations Chitoornatham 0.5 km, West Eguvarpalayam 1.7 km, NNW 10 Densely populated area Chennai city 44.7 km, SSE 11 Inland water bodies Chittoornatham pond 1.0 km, West Pulicat lake 8.1 km, NE Arani river 7.4 km, SSE Pallavada lake 6.6 km, NW 12 Ecologically sensitive zones like Nil Wild Life Sanctuaries, National Parks and biospheres 13 Defense establishments None within 10 km radius 14 Socio-economic factors No Resettlement and Rehabilitation issues 15 Seismicity zone Zone III as per IS: 1893 (Part-1) Nearest sea coast Bay of Bengal 26.7 km, East 17 Reserve forests Puliyur forest 3.1 km, SSW Periyapuliyur forest 4.3 km, SW Pallavakam R.F. 5.6 km WSW Thervoy R.F. 5.7 km, SW Manali R.F. 5.7 km, SSW Siruvada forest 8.2 km, WSW Palem forest 12.3 km, WNW 18 Historical / archaeological Nil within 15.0 km from project boundary places VIMTA Labs Limited, Hyderabad/Coimbatore 10

22 District, Tamilnadu Chapter 1 Introduction 1.4 Scope of the Study With a view to assess the environmental impacts due to the proposed expansion activity ARS availed the services of M/s. Vimta Labs Ltd, Hyderabad / Coimbatore to prepare EIA Report for various environmental attributes including air, noise, water, land and ecology along with parameters of human interest which may be affected and to prepare an EMP for mitigating adverse impacts. This EIA report has been compiled incorporating one season based baseline environmental quality data as per the guidelines and requirements of MoEF, Central Pollution Control Board (CPCB) and Tamil Nadu Pollution Control Board (TNPCB). Environmental baseline monitoring has been carried out during non-monsoon season (1 st May to 31 st July 2014) and used to identify potential impacts. Modeling exercises have been carried out to predict and evaluate impacts. An Environment Management Plan is also delineated Study Area for EIA The study area for EIA study comprises of 10 km radius area around the periphery of existing plant site and the proposed area allotted for the expansion activities. The study area map is shown in Figure-1.2. The scope of the study broadly includes: Field sampling of environmental attributes at various representative locations in the study area to establish the baseline environmental status; Collate and compile secondary data including socio-economic data from published literature / government publications; Estimate pollution loads that would be generated by the proposed project; Predict incremental levels of pollutants in the study area due to the proposed project; Evaluate the predicted impacts on the various environmental attributes by using scientifically developed and widely accepted Environmental Impact Assessment Modeling Methodologies; Prepare an Environment Management Plan (EMP) to mitigate the predicted impacts; and Identify critical environmental attributes required to be monitored during the project execution and to suggest post project monitoring. VIMTA Labs Limited, Hyderabad/Coimbatore 11

23 District, Tamilnadu Chapter 1 Introduction 1.5 Methodology of the Study Reconnaissance survey was conducted by M/s. Vimta Labs Limited, Hyderabad and officials of ARS and sampling locations were identified on the basis of: Predominant wind directions expected during the period of baseline monitoring in the study area and also recorded by Indian Meteorological Department (IMD) Topography and location of surface water bodies like ponds, canals and rivers; Location of villages / towns / sensitive areas; Identified pollution pockets, if any within the study area; Accessibility, power availability and security of monitoring equipment; Areas which represent baseline conditions; and Collection, collation and analysis of baseline data for various environmental attributes. The monitored environmental attributes and frequency of monitoring are presented in Table 1.3. VIMTA Labs Limited, Hyderabad/Coimbatore 12

24 District, Tamilnadu Chapter 1 Introduction TABLE 1.3 ENVIRONMENTAL ATTRIBUTES AND FREQUENCY OF MONITORING Sr. No. Attributes Parameters Frequency 1 Ambient air quality PM 10, PM 2.5, SO 2 and NO X, CO, Pb, As, Ni, C 6 H 6, B(a)P, O 3, NH 3 & Hg 2 Meteorology Wind speed, Direction, temperature, Relative humidity, Rainfall, cloud cover and atmospheric pressure 3 Water quality Physical, Chemical and Bacteriological parameters. As per IS:10500 (2012) 4 Ecology Existing terrestrial and aquatic flora and fauna in the study area Two consecutive days per week at 8 locations One hourly recording of wind speed, wind direction, cloud cover, temperature (13- weeks) at 1 location Grab samples were collected from nine (6 GW + 2 SW) locations once during the study period Through field studies once during the study period and based on the review of secondary data 5 Noise levels Noise levels in db (A) Once during study period at ten locations 6 Soil characteristics Parameters related to At eight locations once agricultural and during the study period afforestation potential 7 Land use Establishing land use Based on the land use data pattern published in District Census Handbook, 2001 & based on Satellite Imagery 8 Socio-economic aspects Socio-economic and work force characteristics and Based on published statistics of 2001 Census other demographic aspects 9 Geology Geological history Geological data based on data collected from secondary sources & based on Satellite Imagery 10 Hydrology (surface & ground) 11 Risk assessment, disaster management plan and occupational health & safety Drainage area and pattern, nature of streams, aquifer characteristics, recharge and discharge areas Identify areas where disaster can occur and identify areas of occupational hazards Based on data collected from secondary sources Based on pool fire modeling and risk assessment studies VIMTA Labs Limited, Hyderabad/Coimbatore 13

25 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description 2.0 PROJECT DESCRIPTION This chapter addresses the details of the proposed augmentation & expansion of thermal power plant (TPP) in context with the basic raw material requirement, processes and capacities, utilities and services, infra-structural facilities, sources of pollution and proposed mitigation measures. 2.1 Type of Project The proposed expansion deals with the augmentation & expansion of existing thermal power plant. Of the existing power plants 1 x 60 MW (60 MW) is operating and the proposed project involves augmentation of another existing 60 MW to 135 MW and erection of additional 350 MW TPP. The existing power plant consists of a 60 MW CFBC pulverized coal fired boiler rated to generate tonnes of steam per hour (TPH). The current expansion involves installation of 135 MW & 350 MW TPP with a boiler rating of 563 TPH & 950 TPH respectively. The superheated steam pressure will be 170 kg/cm 2 and temperature will be 537 ºC with reheat temperature of 537 ºC. Coal required for the plant upon the expansion would be 2.31 MTPA which will be sourced by sea from Indonesia to Ennore port which is located ~50 km by road and thereon through trucks (40 T Container) to the plant site. The total water demand will be about 240 KLD which will be drawn from existing borewells within the plant site. Power evacuation will be from Thervaikandigai, which is located 14.0 km from site and hence a new transmission line will be erected. 2.2 Need for the Project The demand projections on all India basis for the year , and are given in Table-2.1. TABLE-2.1 DEMAND PROJECTIONS Year Electricity Energy Requirement at Annual Peak Electric Load at Power Station Bus Bars (GWh) Station Bus Bars (MW) Justification of the Project Deficit in power supply demand Projected power demand by the end of 12 th five year plan Ever increasing power demand Governments focus of infrastructural development as part of industrialization Hence, the proposed augmentation cum expansion of coal based TPP is justified. VIMTA Labs Limited, Hyderabad/Coimbatore 15

26 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description 2.3 Project Location & Layout The project site is located in Sithurnatham, Sirupuzhalpettai & Eguvarpalayam villages, Gummidipoondi taluk, Thiruvallur district, Tamil Nadu. The map showing the general and specific location of the plant is shown Figure-1.1, 1.2 & 1.3 of Chapter 1. The detail of environmental setting is also given in Table 1.2 of Chapter 1. Layout of the existing power plant has been planned considering the space requirements for all the equipment, systems, buildings, structures, coal storage area and marshalling yard, ash silos, raw water storage tank, water treatment plant etc., Necessary plant drainage system has been provided at the existing plant site and also planned for the proposed additional area for the expansion activities. In laying out various facilities, following general aspects have been taken into consideration: Provision to install 1 X 350 MW TPP (Independent); Coal storage yard for 7 days requirement; Ash silos for fly ash storage; Predominant wind directions as shown in the wind rose to minimise pollution, fire risk etc.; Raw water supply, storage facilities; and Availability of adequate space for fabrication / construction equipment. All facilities of the plant area will be laid out in close proximity to each other to the extent practicable so as to minimize the land requirement. The layout facilitates movement of men and materials between the various facilities both during construction and operation. The layout map showing the plant site and plant boundary is shown in Figure Size or Magnitude of Operation Taking into account, reliability of equipment and matching capacities between the different sections of the plant, the type of equipment/installation system and the departmental capacities at the plant, have been arrived. A condensed description of proposed utilities and major equipment is given in the following sections. The capacity of total power plant after the proposed expansion will be 545 MW [Existing 1 x 60 MW (Sub critical boiler); Proposed 1 x 135 MW (Sub critical boiler) + 1 x 350 MW (Super critical boiler)]. The salient features of proposed power plant are presented in Table-2.2. VIMTA Labs Limited, Hyderabad/Coimbatore 16

27 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description FIGURE-2.1 PLANT LAYOUT VIMTA Labs Limited, Hyderabad/Coimbatore 17

28 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description TABLE-2.2 SALIENT FEATURES OF THERMAL POWER PLANT Sr. No. Features Description 1 Total capacity 545 MW 2 Configuration Under operation: 1 x 60 MW Proposed: 1 x 135 MW + 1 X 350 MW 3 Technology 1 X 60 MW & 1 X 135 MW PF Boiler with re-heat cycle: M.S: 170 kg/cm 2 / 537 O C; Reheat: 537 O C 1 X 350 MW Super Critical PF Boiler with re-heat cycle: M.S: 255 kg/cm 2 / 585 O C; Reheat: 585 O C 4 Boilers 1 x TPH; Sub critical (Existing 1 x 60 MW) 1 x 563 TPH; Sub critical (Proposed 135 MW) 1 x 950 TPH; Super critical (Proposed 350 MW) CFBC/Pulverized Coal fired, natural circulation boilers 5 Generators Three generators with rated 60 MW, 11KV, 50 Hz, 3 ph and 0.8 PF 135 MW, 350 MW 6 Power evacuation Power evacuation will be from Thervaikandigai, which is located 14.0 km from site 7 Condenser Air cooled condenser 8 Auxiliary Cooling System Finfan coolers for cooling of turbine, generator and boiler auxiliaries 9 HFO/LDO Storage Tanks 2 x 300 KL HFO tanks and 2 x 150 KL LDO tanks 10 Switchyard, 230 KV System Generator, Transformer and Station Transformer 11 Fuel Coal 12 Source of Coal Indonesia Coal (Imported) 13 Coal Handling Ground hoppers, stacker, reclaimers and double stream conveying system 14 Coal Requirement 2.31 MTPA at 85% PLF 15 Sulphur content 0.5% 16 Ash Content in Coal 9.0% 17 Ash generation Bottom Ash Fly Ash MTPA MTPA MTPA A B 18 Ash Handling Dry ash collection 19 ESP efficiency 99.99% 20 Stack 145 m AGL [Common for 1 x 60 MW & 1 X 135 MW] 220 m AGL [1 x 350 MW] 21 Total water demand 240 KLD (0.098 cusec) 22 Source of water Existing borewells 23 Project cost INR Crores VIMTA Labs Limited, Hyderabad/Coimbatore 18

29 2.4.1 Land Requirement Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The existing plant operates in an area of ha (62.99 acres). Additionally ha (28.39 acres) of barren land adjacent to the existing site has been acquired for the current expansion activities. Totally the plant upon expansion operates in an area of ha (91.38 acres). Out of which, an area about ha will be used for plant facilities and ha area will be used for greenbelt development. The break up details of the land use is given in Table-2.3. Sr. No. Land Use TABLE-2.3 LANDUSE BREAK-UP Existing (ha) Proposed (ha) Area Upon Expansion (ha) 1 Boiler house Turbine generator hall Air cooled condenser Water treatment plant ESP and stack Switch yard Coal storage yard Greenbelt Raw water reservoir Road area Ash dyke Open area Total % Fuel requirement, Source, Quality & Transportation Fuel Requirement and Source As a coal based thermal power plant, the primary fuel of the plant will be 100% Indonesian coal. The maximum annual coal consumption for the plant after expansion will be about 2.31 MTPA. Coal requirement details along with its source are presented in Table 2.4. Coal from Indonesia would be transported through sea to Ennore port and thereon through trucks to the existing plant site. The coal requirement for the proposed power plant is based on PLF : 85% Plant heat rate : 2500 kcal/kwhr Gross Calorific value : 4,500 kcal/kg Secondary fuel Light Diesel Oil (LDO) will be used only for cold start and Heavy Fuel Oil (HFO) will be used as support fuel at low loads and flame stabilization. The required quantity will be brought to plant site via road transportation. VIMTA Labs Limited, Hyderabad/Coimbatore 19

30 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description TABLE-2.4 COAL CONSUMPTION Coal Consumption Sr. No. Power Generation Upon expansion Existing (TPD) (TPD) 1 1 x 60 MW 1,000 1, x 135 MW -- 1, X 350 MW -- 4,760 Total 1,000 7,712 Annual requirement 0.30 MTPA 2.31 MTPA TABLE-2.5 INDONESIAN COAL CHARACTERISTICS Power Evacuation Sr. No. Particulars Properties 1 Gross Calorific Value 4,500 kcal/kg 2 Moisture 9.0 % 3 Ash 9.0% 4 Fixed Carbon 41.0% 5 Sulphur 0.5% 6 Volatile Matter 39.0 % Power evacuation will be from Thervaikandigai, which is located 14.0 km from site and hence a new transmission line will be erected Man power requirement The total manpower of the existing plant is about 150 employees. Upon expansion, additional 200 employees will be required, which includes officers and supervisors also. The break-up of manpower requirement is given in Table-2.6. TABLE-2.6 MAN POWER DEMAND Sr. No. Category No. of persons 1 Managers / officers 20 2 Technical / administrative assistants 40 3 Skilled /semiskilled workers 140 Total 200 VIMTA Labs Limited, Hyderabad/Coimbatore 20

31 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Water Requirement The water requirement of the existing and the proposed activity will be obtained from the existing borewells itself. Rain water harvesting reservoir (70 MLD) has been constructed for harvesting rainwater through storm water drains. Additional rain water reservoir is also proposed to be constructed for additional water demand for the expansion activities. The total water demand for the plant after the proposed expansion will be 240 KLD with a daily fresh water requirement of KLD. About KLD of treated wastewater will be reused for the process requirement (Boiler make-up / DM Plant). The break-up of the water requirement details are given in Table TABLE-2.7 WATER DEMAND Sr. No. Power Generation Water Requirement Existing (KLD) Upon expansion (KLD) MW x 135 MW + 1 X 350 MW Total (0.039 cusec) (0.098 cusec) Description Water Quantity (KLD) DM water for boiler make-up Domestic consumption 16.0 DM plant regeneration 31.0 Total 240 (0.098 cusec) VIMTA Labs Limited, Hyderabad/Coimbatore 21

32 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Ground Water /Rain Water Reservoir Boiler Make-up 1 x 60 MW Boiler Make-up x 135 MW & 1 x 350 MW All Values are in KLD 173 Raw Water 240 Cooling Pond I Cooling Pond II DM PLANT 1 x 60 MW 25 DM PLANT 25 1 x 135 MW & 1 x 350 MW 6 31 Neutralization Pit Domestic Consumption 1 x 60 MW 4.8 Guard Pond 10 Domestic Consumption 1 x 135 MW & 1 x 350 MW 8.0 STP Greenbelt RO Plant Ash Quenching & Coal Dust Suppression R O Rejects FIGURE WATER BALANCE (UPON EXPANSION) VIMTA Labs Limited, Hyderabad/Coimbatore 22

33 2.4.6 Infrastructure Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Availability of infrastructure facilities like railways and road access to the site for ease of transportation of equipment and fuel etc.; Facility for interconnection with transmission and distribution system for evacuation of power; Optimum investment requirement for development of the infrastructure; and Availability of medical, education, market and railway station within an accessible distance. Roads The approach road for the plant will be from NH 5. As a national highway, the road will be suitable for carrying heavy equipment. The internal roads are available to provide access to different areas of the plant. All internal plant roads will be 7.0 m wide black topping with 1.5 m wide shoulders on both sides of the road. Single lane roads will be of 4.0 m wide black topping with 1.0 m wide shoulders on both sides of the road. Access roads to building/facilities will generally be single lane roads without shoulders. Drainage Lined open drains are being provided at the plant site to carry the surface runoff; these drains will run alongside the roads and will lead to the final disposal point. Plinth protection provided around buildings will slope to the drains. Reinforced concrete culverts or concrete pipe culverts will be provided at road crossings. Sewerage System Sewage from the existing plant and from the proposed buildings and facilities will be routed into a sewage treatment plant through a sewerage concrete pipe. Manholes shall be provided at every junctions. A permanent sewage treatment plant shall cater to the sewage discharge of the plant. The treated water will be utilized for the greenbelt maintenance. Landscaping Landscaping has been already developed within the existing plant premises and will also be developed for the additional plant area. Necessary afforestation/ green belt development work will be carried out as per the stipulation of Ministry of Environment & Forests. Plants and tree saplings planted will be maintained and irrigated by usage of treated sewage from the plant. VIMTA Labs Limited, Hyderabad/Coimbatore 23

34 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Infrastructure for Labour The basic amenities for the labour force during erection and operation phase are proposed. The facilities comprises of the following: Separate shelters will be provided for male and female labours for resting; Separate wash rooms (sanitary facilities) will be provided for male and female labours; The contractors will be directed to provide fuel to labours for cooking; First aid facilities will be made available; and Drinking water will be provided. 2.5 Project schedule for Implementation The erection and commissioning activities for the proposed expansion will be completed by December, 2017 subject to receipt of all approvals from statutory authorities. i. BTG orders to place - October, 2015; ii. Commencement of civil works - December, 2015; iii. Commencement of boiler erection - April, 2016; iv. Boiler hydro test - March, 2017; v. Synchronization - November, 2017; vi. Commissioning - December, Technology and Process Description Various utilities are being maintained and will be provided for the smooth and efficient functioning of the existing & proposed plant. The proposed utilities are discussed in subsequent sections. The process flow of the plant is given in Figure Plant Layout The general topography of the land for the main plant is plain. The land area is free of any forest and with minimum habitation. No cultivation is being carriedout in the additional land allotted for the proposed unit. The general layout plan for the proposed units (1 x 135 MW & 1 X 350 MW) has been worked out taking into consideration the various aspects like available land, ground features, ground contour, corridor for outgoing transmission lines, road/rail approaches, railway siding arrangement for coal transportation, wagon tipplers, prevailing wind direction and location of ACC, strategically locating major plant equipment etc., An area of 5.69 ha has been identified for installation of the proposed 1 x 135 MW & 1 x 350 MW units. This land area is considered including space for installation of boilers (0.78 ha), turbine generator hall (0.82 ha), air cooled condenser (1.54 ha), water treatment plant (0.35 ha), ESP & chimney (0.53 ha), Switch yard (1.67 ha). Coal storage yard has been proposed in an area of 1.55 ha. Buffer zone for plantation as required for such installation has also been considered. VIMTA Labs Limited, Hyderabad/Coimbatore 24

35 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Ash dyke (Existing 0.64 ha + Proposed 2.61 ha = 3.25 ha) is allocated for temporary dumping of bottom ash (6 years) and unsold fly ash for approx. 2 years. Considering 15 M height (5m below ground and 10m above ground), about 3.25 ha of land has been earmarked for dumping ash generated from the plant for a period of 2 years (As per CEA norms, Beginning from the 1st year, every year 10% of the Fly ash to be utilized and after 10 years 100% Fly ash generated should be utilized). This will cater for dumping of bottom ash for 6 years and 10% quantity of fly ash for 2 years. It is proposed to fill the low lying areas in the vicinity with the bottom ash for area development. Bottom ash also has a ready market as building material for uses such as landfill etc. Entrepreneurs will be encouraged to use fly ash for manufacturing bricks, tiles, light aggregates etc., Greenbelt will be provided in the proposed plant area in addition to the existing greenbelt all along the periphery of the plant site boundary, ash dyke area, partly along raw water reservoir area and any vacant area lying within the plant site Mechanical Equipment and Systems Thermodynamic Cycle The proposed units will be a conventional thermal power plant operating on sub critical pressure (1 x 135 MW) & super critical pressure (1 x 350 MW), single reheat steam cycle with regenerative feed heating arrangement. Sub critical operation (Exis. 1 x 60 MW; Prop. 1 x 135 MW) The superheated steam from the boilers at 170 bar and 537ºC is supplied to the High Pressure (HP) turbine. This steam, after expansion in the HP turbine is sent back to the boiler as cold reheat steam. After reheating in the boiler, the reheated steam (Hot reheat steam) at about 42 bar and 537 ºC is sent to Intermediate Pressure (IP) and Low Pressure (LP) turbine and is finally exhausted into the condenser. The exhaust steam is cooled and condensed in the air cooled condenser. VIMTA Labs Limited, Hyderabad/Coimbatore 25

36 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description FIGURE-2.3 POWER GENERATION FLOW SCHEME VIMTA Labs Limited, Hyderabad/Coimbatore 26

37 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The feed heating system consists of 4 stages of low pressure (LP) heaters in series, one gland steam condenser, one separate drain cooler for low pressure heater, one deaerator and 3 stages of high pressure (HP) heaters in series. The condensate from the hot well of each condenser is extracted by 2 x 100% capacity condensate extraction pumps (1W + 1S) and is pumped to the deaerator through gland steam condenser, drain cooler and LP heaters. The feed water is de-aerated in the deaerator and is collected in feed water storage tank. Water from this tank is drawn by the boiler feed pumps and is pumped to the boiler through the HP heaters. 3 x 50% capacity feed water pumps have been envisaged for each unit. Condensate in the LP heaters and feed water in HP heaters is heated progressively by bled steam drawn from Cold reheat line and extraction steam of the IP and LP turbine. Condensate drain from the HP heaters will be cascaded to the deaerator feed storage tank and drain from the LP heaters would be cascaded to the condenser through the drain cooler. The auxiliary steam for the power station is drawn from main steam line and after pressure reduction and desuperheating is used for de-aeration, turbine gland sealing, etc. Provision for steam supply to auxiliary steam system from cold reheat piping through adequately sized pressure reducing and desuperheating station will also be there. The unit is also provided with HP and LP bypass system for quick hot start and boiler stability with large load rejections. Description of major plant and equipment of a typical power plant unit is given hereunder. Steam generator & accessories The steam generator which would be designed for firing 100% coal would be radiant, reheat, natural circulation, single drum, balanced draft. Semi-outdoor type of unit rated to deliver t/hr of superheated steam at 170 bar, 537 O C when supplied with feed water at a temperature of C at economiser inlet. The steam generator would be provided with six mill type coal pulverisers along with individual raw coal feeders and coal bunkers. The boiler would be designed to handle and burn HFO/LSHS oil as secondary fuel up to 22.5% MCR capacity for startup and low-load operation. The boiler would also be provided with light diesel oil (LDO) firing system having a capacity corresponding to about 7.5% MCR for warm-up during start-up. The required fuel oil and light fuel oil pressurizing units and fuel oil heating equipment will be provided. High energy arc (HEA) ignitors would be provided to ignite LDO as well as fuel oil. VIMTA Labs Limited, Hyderabad/Coimbatore 27

38 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The steam generator would consist of a corner fired water cooled furnace, radiant and convection superheaters, reheaters, attemperators, economiser, regenerative air heaters, Steam coil air heaters etc. The draft plant comprises 2x60% axial forced draft fans, 2x60% radial induced draft fans and 2x60% radial type primary air fans. Electrostatic precipitators and fly ash hoppers with associated ducting/piping would be provided for the collection of ash. Soot blowers would be provided at strategic locations and would be designed for sequential automatic operation from the unit control room. Turbine Generator Unit The steam turbine would be rated for 135 MW maximum continuous output, at the generator terminals, with throttle steam conditions of 170 bar pressure and 537 O C superheat, 537 O C reheat temperature, kg/cm 2 back pressure and, all feed water "heaters in service. The steam turbine would be a reheat, condensing unit tandem compound with a double exhaust LP turbine. The generator would be rated for 135 MW, 3 phase, 50Hz, 3000 rpm and 0.8 pf. The generator stator would be water cooled. The rotor would be suitable for conventional hydrogen cooling, with the windings cooled with hydrogen circulated by fans mounted on the rotor. The turbine-generator would be complete with all accessories customarily supplied by turbine-generator manufacturer such as protective system, lube and control oil systems, seal oil system. Jacking oil system, seal steam system, turbine drain system. HP/LP bypass system. Electro-hydraulic control system, automatic turbine run-up system. on-line automatic turbine test system and turbine supervisory instrumentation. The turbine-generator would also have all necessary indicating and control devices to permit the unit to be placed on turning gear, to be rolled, accelerated and synchronized automatically from the control room. Other turbine-generator accessories would include an oil purification unit with transfer pumps and clean and dirty oil storage tanks of adequate capacity. The condensing plant would comprise double-pass surface type condenser of single shell construction. The condenser would be mounted on spring supports designed to take up its own and turbine exhaust hood thermal expansion. 1x100% capacity priming vacuum pump would be provided to create vacuum in the condenser during start-up and 2x100% capacity main vacuum pumps to remove the non-condensible gases liberated during normal operation. Mechanical vacuum pumps are motor driven and unlike steam jet air ejectors do not require any motive steam. Vacuum pumps are therefore more convenient for unit start-up and are preferred. VIMTA Labs Limited, Hyderabad/Coimbatore 28

39 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The unit would be provided with a 60% HP-LP bypass system. a) To prevent a boiler trip in the event of a full export load throw-off and maintain the unit in operation at house load. b) To prevent a boiler trip following a turbine trip and enable quick restart of the turbo set. c) To minimise warm restart deviations of the unit after a trip. d) To conserve condensate during start-up e) To facilitate quick load changes in both directions without affecting the steam generator operation during start-up. Air Cooled Condenser Air cooled condenser is typically of A-frame design. This design not only facilitates condensate draining and collection but it also ensures that there is no dead zone in the heat transfer surface and there is high operating stability during load transients. The vapour inlet header constituents the apex of the A. A large diameter and comparatively lengthy pipe connects this header to the exhaust from low pressure stage of the turbine and its large volume makes this inlet subsystem prone to air leakage as well as requiring a longer time to evacuate during plant start up. At the bottom of the A-frame are two outlet headers, each connected to the inlet headers by banks of finned tube. Most of the panels on ACC are of parallel type, both condensing vapour and condensate flow together down insides of the pipe. Piping also connects the two outlet headers together, allowing the vapour to pass from one side to other as well as the condensate to be collected. Whereas in counter flow arrangement, the vapour rising up into the tube banks from outlet headers while the condensate flows back down to these headers so that it can be collected and withdrawn. Meanwhile, the upper ends of the tubes in these section are connected to their own headers which are provided with steam jet air ejectors for removal of non-condesibles. The finned tubes are necessary because of the low thermal conductivity, low density and low heat capacity of air. The large surface area required to obtain a given heat removal rate, the area increasing with the design ambient air temperature. Major components of ACC Condensing & venting modules Air movement equipments Windwall andmodule partition walls Air evacuation equipment with piping Condensate collection headers Condensate storage tank and pumping system Exhaust steam ducting with expansion joints VIMTA Labs Limited, Hyderabad/Coimbatore 29

40 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Fin cleaning system Instrumentation & controls Pressure relief device (rupture disc)for protection of ducting Steam duct condensate draining system Electricals VFD, MCC, cables etc Wet Cooling System vs Dry Cooling System Air cooled condenser have become the need of the hour than the conventional method due to depletion of the water source. It is very well known fact, water is becoming a scarce natural source. Using water for thermal power plant has negative impact on environment and ecology. Besides this cost of storage, pump and treatment of water for cooling power application is a major concern. System Wet Cooling System Dry Cooling System Availability of coolant Water is scarce hence it Air is free has become costly Maintenance cost High 25 % of wet cooling system Effluent treatment Necessary Not required Fouling and Scaling Major concern Not required Cleaning Frequent tube cleaning is required Occasional fin cleaning is required Infrastructure Pumping system and Not required storage system required Annual energy consumption High Low Condensing Equipment and Accessories Condensate Pumps Two 100% capacity condensate pumps, one working and one standby would be provided. The pumps would be vertical, canister type, multistage centrifugal pumps driven by AC motors. Boiler Feed Pumps Three 50% capacity motor driven boiler feed pumps would be provided to pump the feed water from the deaerator to the steam generator through the high pressure heaters. Two pumps would normally be in operation, with the third as standby. The boiler feed pumps would be horizontal, multistage centrifugal pumps of barrel type. Each boiler feed pump would be provided with a booster pump driven from the same shaft as the main pump. Each boiler feed pump would be provided with a variable speed hydraulic coupling, with built-in step-up gear to regulate the boiler feed pump speed. Low Pressure Heaters The three low pressure heaters, namely 1, 2 & 3 would be of surface type designed for vertical mounting with U-shaped stainless steel tubes, with their VIMTA Labs Limited, Hyderabad/Coimbatore 30

41 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description ends rolled in carbon steel tube sheets. Low pressure heater No.1 would be provided with an external drain cooler. Deaerator The deaerating feed water heater would be a direct contact, variable pressure type of heater with a spray or spray tray type of deaeration arrangement. The feed water storage tank would have a storage capacity adequate to feed the boiler for 10 minutes when operating at MCR conditions. Gland Steam Condenser A surface type gland steam condenser would be used to condense the gland steam exhausted from the turbine glands. The gland steam condenser would be of single-pass type with the main condensate flowing through the tubes to condense the steam. Exhausters would be provided to evacuate the air from the shell side and maintain the shell at the required negative pressure. High Pressure Heaters The two high pressure heaters, namely 5 & 6 would be of surface type designed for vertical mounting with stainless steel-tubes welded into stainless steel clad tube sheets. Both HP heaters would be provided with a desuperheating zone and a drain cooling zone in addition to the condensing zone. Super critical operation (Proposed 1 x 350 MW) Steam Generator The Steam Generator shall be of forced or assisted circulation with super-critical steam parameters, once through type, single reheat arrangement for firing pulverized coal. The steam generator shall be drum less, but shall include two (2) nos. of separators and 1 x 100% start-up drain recirculation pump along with all other necessary auxiliaries. TABLE-2.8 STEAM GENERATOR SPECIFICATIONS Sr. No. Parameters Data 1 Main Super-heated steam pressure 258bar (a) 2 Main Super-heated steam temperature 588ºC 3 CRH inlet pressure bar (a) 4 CRH inlet Temperature 343ºC 5 HRH outlet pressure bar (a) 6 HRH outlet temperature 585ºC 7 Feed water inlet temperature 289 ºC 8 Fuel used Raw Coal LDO for start-up & HFO for stabilization up to 30% BMCR condition 9 Gross Calorific value of Coal 4220 Kcal/Kg - Imported coal VIMTA Labs Limited, Hyderabad/Coimbatore 31

42 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The steam generator shall be designed for satisfactory, continuous and reliable operation at high efficiency with the range of coal being provided to this thermal power plant with minimum requirement of support fuel oil for flame stabilization within its control range. The furnace design shall have adequate residence time provided to burn the fuel completely. The Steam Generator shall be designed to fire the blended coal having 70% of imported coal and 30% of Indian coal. Each steam generator shall have suitable pulverized coal firing arrangement comprising coal bunkers with 16 hours storage capacity. Gravimetric raw coal feeders, pulverizing mills (vertical/horizontal) and other required auxiliaries will be installed. The milling system will be sized to ensure rated performance for lifetime. Selection of the number of mills shall consider one ready standby pulveriser mill to achieve BMCR while the steam generator is fired with worst coal. The mill capacity selection shall be based on 90% loading with worst coal with all mills operating. The steam generating unit shall be provided with LDO pressurizing units for supplying LDO to oil burners during boiler cold and hot start-ups and HFO for flame stabilisation with coal firing during low load operations up to maximum 30% BMCR load. For maintaining the steam temperature control range (rated steam temperature of 569 ± 5 C) within the prescribed limits at the outlet of super-heater and reheater, de-superheating stations will be provided. The water required for desuperheating shall be tapped off at the outlet of the steam generator feed water pumps to control the final steam temperature between 60% to 100% MCR load. Tilting Burners will also be used to control Reheat temperature 2 x 60% RAPH will be provided for each steam generator for primary and secondary air heating. SCAPH will be provided at the discharge duct of each F.D. fan, and will be installed close to the regenerative air heater. The SCAPH will be of modular construction type with fin tubes and will be designed to maintain the cold end temperature above acid dew point temperature during steam generator start-up and low load operations. The steam generator balanced draft system per unit will be provided with two (2) sets of FD fans, two (2) sets of ID fans, and two (2) sets of PA fans; each set rated for 60% of BMCR (Steam generator MCR) capacity. The FD fans may be of constant speed, axial flow type with hydraulic blade pitch control; ID fan of radial, backward curved type with VFD and the PA fan of constant speed, centrifugal type with variable blade pitch control. All necessary regulating and isolating dampers will be provided to all fans for safe, efficient and convenient operation of the steam generator. VIMTA Labs Limited, Hyderabad/Coimbatore 32

43 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Turbine Generator Unit The steam turbine would be tandem compounded, single reheat, condensing, horizontally split machine with uncontrolled extractions for Four (4) LP heaters, Three (3) HP heaters and One(1) Deaerator. The steam turbine will consist of proven HP turbine, IP turbine, and LP turbine modules. However the final number of heaters will depend upon the steam turbine supplier selected for this project. The turbine will have a lubricating oil system for supplying oil to turbine and generator bearings and also to hydrogen seal oil system of the generator. The lubricating oil will be cooled by closed circuit cooling water system water as cooling medium. Necessary protective & supervisory system will be provided to ensure troublefree, safe and efficient operation of the turbine generator. TABLE-2.9 TURBINE SPECIFICATIONS Sr. No. Design Description Units Parameters 1 Main Steam Inlet Pressure Bar(a) Main Steam Inlet Temperature ºC Reheat steam inlet pressure Bar(a) Reheat steam inlet temperature ºC Exhaust pressure Bar(a) Feed water temperature at last HP heater outlet ºC Valve Wide Open Flow % MCR Turbine rating MW 350 The generator would be rated suitably with 3 phase, 50Hz, 3000 rpm and 0.8 pf. The generator stator would be water cooled. The rotor would be suitable for conventional hydrogen cooling, with the windings cooled with hydrogen circulated by fans mounted on the rotor. The turbine-generator would be complete with all accessories customarily supplied by turbine-generator manufacturer such as protective system, lube and control oil systems, seal oil system. Jacking oil system, seal steam system, turbine drain system, HP/LP bypasses system, Electro-hydraulic control system, automatic turbine run-up system, On-line automatic turbine test system and turbine supervisory instrumentation. The turbine- generator would also have all necessary indicating and control devices to permit the unit to be placed on turning gear, to be rolled, accelerated and synchronized automatically from the control room. Other turbine-generator accessories would include an oil purification unit with transfer pumps and clean and dirty oil storage tanks of adequate capacity. The condensing plant would comprise of Air cooled condenser of single row construction. 1 x 100% capacity priming vacuum pump would be provided to create vacuum in the condenser during start-up and 2 x 100% capacity main VIMTA Labs Limited, Hyderabad/Coimbatore 33

44 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description vacuum pumps to remove the non-condensable gases liberated during normal operation. Mechanical vacuum pumps are motor driven and unlike steam jet air ejectors do not require any motive steam. Vacuum pumps are therefore more convenient for unit start-up and are preferred. The unit would be provided with a 60% HP-LP bypass system. i. To prevent a boiler trip in the event of a full export load throw-off and maintain the unit in operation at house load; ii. To prevent a boiler trip following a turbine trip and enable quick restart of the turbo set; iii. To minimise warm restart deviations of the unit after a trip; iv. To conserve condensate during start-up; v. To facilitate quick load changes in both directions without affecting the steam generator operation during start-up. Condensate Pumps Unit shall comprise of 3 x 50% capacity CEPs. The CEP will be designed for 10% Margin in capacity and 10% margin in head over and above the pump sizing consideration indicated below. The condensate extraction pumps will be vertical; multi stage, enclosed can type with flanged connection driven by electric motor. Boiler Feed Pumps Three 50% capacity motor driven boiler feed pumps would be provided to pump the feed water from the deaerator to the steam generator through the high pressure heaters. Two pumps would normally be in operation, with the third as standby. The boiler feed pumps would be horizontal, multistage centrifugal pumps of barrel type. Each boiler feed pump would be provided with a booster pump driven from the same shaft as the main pump. Each boiler feed pump would be provided with a variable speed hydraulic coupling, with built-in step-up gear to regulate the boiler feed pump speed. Regenerative Feed Water Heating System Regenerative feed heating system is envisaged for the turbine cycle to improve the efficiency. The feed heating system with four (4) numbers of LP heaters, one number direct contact type deaerating heater and three (3) numbers of HP heaters are foreseen for this type of unit. HP and LP feed heaters will be tube and shell type. LP feed heaters will be of horizontal and U-tube type with integral drain cooler. HP heaters will be horizontal and U-tube type with integral desuperheating, condensing and drain cooling sections Deaerator For deaerating and heating of the feed water the unit will be provided with a spray-cum-tray type deaerating heater with a horizontal feed water storage tank of 6 minutes capacity of steam generator MCR condition. The deaerator will be capable of deaerating all the incoming condensate from LP feed water heaters and drains from HP feed water heaters to provide steam generator feed to match VIMTA Labs Limited, Hyderabad/Coimbatore 34

45 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description the steam generator MCR requirements continuously. The deaerator will be designed to keep the oxygen content of the condensate below cc/litre with zero carbon dioxide. Deaerator will normally operate by taking extraction steam from IP turbine casing. However, during low load operation and start-up, the deaerator will be pegged with steam drawn from auxiliary header Gland Steam Condenser A surface type gland steam condenser would be used to condense the gland steam exhausted from the turbine glands. The gland steam condenser would be of single-pass type with the main condensate flowing through the tubes to condense the steam. Exhausters would be provided to evacuate the air from the shell side and maintain the shell at the required negative pressure. Condensate Polishing Unit Online condensate polishing unit of full-flow Mixed bed type is envisaged to treat the condensate to maintain desired quality of condensate water as recommended by BTG manufacturer. The CPU shall also be capable of maintaining the desired condensate quality during start-up and condenser tube leakage Electrostatic Precipitator (ESP) Steam generating unit shall be provided with the required electrostatic precipitator (ESP). ESP shall have two parallel gas paths; one gas path can be isolated for maintenance while the other path being in operation. Each path shall comprise of the required number of fields in series for collection of fly ash. The ESP will have efficiency of around 99.9%. The ESP will have adequate number of ash hoppers provided with electric heaters. ESP will be provided with Microprocessor based controller. The design of ESP shall be such that the outlet dust burden or solid particulate matter (SPM) content at its outlet does not exceed 50 mg/nm³ at 100% BMCR with worst coal, with one field out of service. 2.7 Plant Water System The requirement of water for the plant will be for meeting the following requirement: i. Make-up For the re-circulating Auxiliary cooling water system ii. Power cycle make-up (through D.M plant) iii. Make-up to the air-conditioning and air washer system iv. Drinking Water v. Service Water vi. Dust suppression system vii. For maintaining greenery The source of water for the plant is existing borewells & rain water harvesting system. Water will be collected in a raw water reservoir through a well-developed rain water harvesting system and the plant drains which will be pre-treated and VIMTA Labs Limited, Hyderabad/Coimbatore 35

46 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description then treated to the required levels for usage in the plant. The total water demand of the TPP is 240 KLD. A raw water reservoir of 60 MLD capacity is established which would cater to the required water quantity. From the plant water reservoir, the water is fed to clarifiers. Clarified water will be feed for Filtration Plant, which will cater the needs of treated/soft water requirements of the plant. Raw Water reservoir A raw water reservoir of capacity 60 MLD is provided. The raw water reservoir at site will be of earthen construction with suitable lining. Water Pre-Treatment Plant The purpose of pre-treatment system is to treat the raw water from raw water storage tank and reduce the suspended solids and any organics prior to downstream use. Raw water is pumped by means of 2 x 100% plant make up pumps through 2 x 50 % Solid Contact Clarifiers for reduction of suspended solids. The overflow of the clarifiers will be taken to clarified water storage RCC tank. The clarified water feed to the DM plant will be pumped through multimedia filters for further reduction in suspended solids and led to a filtered water storage tank for downstream use. The clarified water is used for: i. Makeup for HVAC system; ii. Service water system; iii. Fire water system. Filtered water is also used for potable water requirement after suitable chlorination. Filtered water storage tank will have a total capacity of 8 hours consumptive requirements. The filtered water is used as i. Inlet water to DM plant; ii. Potable water; iii. Coal handling plant requirements other than dust Suppression Plant and equipment use including boiler blow down tanks quench; iv. Miscellaneous uses. Pre-treatment chemicals such as alum, lime and polyelectrolyte will be dosed at inlet to the clarifier. A sludge sump will be provided and the collected sludge will be transported to sludge thickener for further treatment and disposal. Chlorination with sodium hypochlorite will be done at the outlet of clarifier. The pre-treatment plant will be complete with 2 x 50% Solid Contact Clarifiers and associated chemical storage, handling and dosing system, sludge handling system, 2 x 100% multi grade filters, backwash pumps, backwash waste collection tank and transfer pumps, RCC clarified water storage tank, filtered water storage tank, all piping, valves and instruments as required. The system is sized based on the Design Raw Water Analysis. The clarified water and filtered water requirement will be based on downstream consumptions of systems. VIMTA Labs Limited, Hyderabad/Coimbatore 36

47 DM Plant Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The purpose of the Cycle Make-Up Treatment (DM) System is to produce Demineralized water of required quality and quantity for steam cycle. The DM plant will treat filtered water to produce Demineralized water for make up to steam cycle, closed cooling water system and miscellaneous use during maintenance operation. 2 X 100% (1W + 1 S) each of 35m³/hr (Net Output Capacity) streams will be provided. The net demineralized water that can be produced from each stream will be 700 m³/day. The Cation & Anion Exchangers service and regeneration cycle is 20 hours and 4 hours respectively. Mixed Bed (MB) unit will be regenerated once in 7 days. Regeneration of Cation & Anion vessels is by counter current mode and regeneration of MB is in concurrent mode. The DM water is stored in two DM water tanks of each capacity 500 m3. It is further distributed to various user points. Regeneration system for Cation Exchangers consists of Acid Storage Tank and Acid Measuring Tanks for Cation exchanger and Mixed Bed (Cation) Exchanger. Regeneration system for Anion Exchanger consists of Caustic Storage tank and Caustic Dilution Tank for Anion exchanger, Neutralization pit and Mixed Bed (Anion) exchanger. Transfer Pumps are envisaged for Transfer of Acid/Alkali from tankers to the storage tanks. Ejectors are used for injection of Regeneration chemicals. Acid & Alkali storage tanks will be sized to store 30 days requirement of chemicals. Waste Water Treatment System The Waste Water Treatment system envisaged will cover all the plant wastewater which are to be disposed. The objective of the treatment is to make the wastewater suitable for disposal as per the guidelines of the State Pollution Control Board (PCB). All the wastewater after treatment will be fed to the common monitoring basin to ensure that the effluent meets the PCB stipulations before reuse within the plant and or disposal outside the plant. The details of various waste water sources and their treatment schemes are given in Table VIMTA Labs Limited, Hyderabad/Coimbatore 37

48 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description TABLE-2.10 SOURCES OF WASTEWATER AND ITS MANAGEMENT Sources of wastewater Runoff Water From Coal Yard Runoff Water From Limestone Yard Neutralized Waste Water Treatment & Disposal The runoff from the coal yard will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt The runoff from the limestone yard will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt Make-up water treatment plant waste will be taken to separate neutralization pit, neutralized and then pumped to the Common Monitoring Basin (CMB) Oily Waste Water Oil bearing effluent generated from fuel oil handling area plant floor wash etc. will be treated in an oil/water separator to separate oil from water and the treated waste water sent to CMB. The oily sludge will be collected and disposed offsite Sewage Water from Toilets in the Power Plant The Sewage water generated from the Power Plant will be treated in an anaerobic filter and the treated effluent will be collected and used for horticulture. Suitable arrangements for collection of sludge, its compaction and safe disposal will be provided Boiler Blow Down Boiler blow down waste water will be fed to neutralization pit of water treatment plant and from there it will be sent CMB Special Waste Water Special waste water like Air Preheater washing water, acid cleaning of boiler etc. will be collected and treated in a chemical waste cleaning plant to make it suitable for offsite disposal Clarifier Sludge The sludge collected in the clarifier will be taken to a sedimentation tank and the clear water will be sent to CMB. The collected sludge will be taken to a sludge drying bed and spread over the green belt within the plant boundaries Common Monitoring Basin The outlet from the CMB after ensuring that the quality meets the requirements stipulated in the PCB norms, will be used for coal yard dust suppression, limestone dust suppression and watering of green belt VIMTA Labs Limited, Hyderabad/Coimbatore 38

49 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Chlorination System Raw water chlorination plant is required to dose chlorine in the clarifier during pre-treatment stage. It is dosed to remove the organic matters present in the raw water. Sodium hypochlorite dosing will be provided for chlorination of raw water. The chlorination system consists of sodium hypochlorite dosing tank and dosing pumps. Chemical Feed System Although high purity water will be used as heat cycle make-up, careful chemical conditioning of the feed steam condensate cycle is essential as a safeguard against corrosion and possible scale formation due to ingress of contaminants in the make-up system. Chemical feed system will comprise of the following: A) Hydrazine System The most harmful contaminant, which is always present in the make-up water, causing serious corrosion in the high-pressure boiler is dissolved oxygen. Hydrazine solution will be used as a de-oxygenator, to wipe off traces of dissolved oxygen left over in the feed water after deaerator. Hydrazine solution will be prepared in a solution tank. Water from the condensate pump discharge header will be used as the diluting medium. Dosing pump will deliver hydrazine solution at controlled rates continuously at the condensate pump discharge headers and/or boiler feed pump suction lines. A dosing pump will be provided. B) Phosphate Dosing System The rate of corrosion on mild steel surface is lowest when the solution in contact has a ph within 9 to 10. Proper attention is required so that the alkalinity does not become excessive, as in such case the corrosion rate will go on increasing. To impart desired alkalinity to boiler water and also to safely remove scale-forming compound in water, if any, due to system contamination as non-adherent harmless precipitate, tri-sodium phosphate solution will be added in the boiler drum. Phosphate solution will be prepared in a common tank. Water from the condensate pump discharge header will be used as the solvent. The solution will be transferred to individual metering tanks, from which respective phosphate dosing pumps will inject the solution to respective boiler drums are required. Potable Water Treatment Plant The purpose of potable water treatment system is to treat the water from filter water tank to disinfect prior to downstream use. Filtered water, from filtered water tank, is pumped to the overhead potable water storage tank. This water is chlorinated by dosing sodium hypochlorite in the line for disinfections and makes the water suitable for potable purposes. VIMTA Labs Limited, Hyderabad/Coimbatore 39

50 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Service Water System Clarified water will be used as service water. Clarified water will be pumped from the clarified water storage tank with the help of 2 x 100% service water transfer pumps to overhead service water tank. Further distribution for various points of use will be done from this tank by gravity except for boiler floor wash for which the water will be pumped using booster pumps. Closed cooling Water (CCW) System The CCW system will be provided as part of the SG & auxiliaries and STG & auxiliaries which will meet the cooling water requirements of all the auxiliary equipment of the STG and SG units such as turbine lube oil coolers, generator air cooler, exciter air coolers, ID/SA/PA fan bearing oil coolers, BFP auxiliaries such as lube oil coolers, working oil coolers, drive motors, etc., condensate pump bearings and sample coolers. The total estimated aux. cooling water requirement for the above auxiliaries is about 2500 m³/hr. A closed loop system using passivized DM water is proposed for the CCW system. In CCW system, DM water is circulated by 2 X100% capacity each Closed Cooling Water (CCW) pumps. The hot water from these auxiliaries is cooled in the plate type CCW heat exchangers 2 No (1 W+1S). An overhead expansion tank of adequate capacity is proposed to ensure positive suction to the CCW pumps and also serve as the source of make-up to the CCW system. Normal make- up to the CCW expansion tank is provided from the DM water make up pumps. To minimize the corrosion, a corrosion inhibiting chemical solution will be added to the CCW system. 2.8 Coal handling system Design Criteria, Assumptions and System Capacity Coal will be received in trucks from nearest Port and unloaded using hydraulic tippers / unloading hoppers for tipper trucks. Belt conveyors, stacking, and reclaiming, screening, crushing and conveying same to steam generator bunkers is based on the following functional requirements and assumptions: Coal required for 1 x 350 MW unit at MCR condition based on worst coal having a gross calorific value of 4000 Kcal/kg is TPH; Storage capacity of stockpile is considered Seven (7) days at plant site. The calculations for Coal handling system capacity considering Worst type coal are given in Table VIMTA Labs Limited, Hyderabad/Coimbatore 40

51 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description TABLE 2.11 DETAILS OF COAL HANDLING SYSTEM CAPACITY Sr. No. Description Units Design Coal 1 Calorific value Kcal/kg MCR fuel consumption TPH Coal consumption per day TPD No. of hours of CHS operation per day hours 12 5 Average capacity of coal plant for TPH 250 1x350MW plant 6 Rated capacity of System selected considering 12 hrs operation of the plant TPH 500 The estimated maximum daily coal consumption for the power station will be around 4760 tonnes. It is considered that coal of size (+) 50 mm will also be received in the station. Coal receipt, storage and Handling system Raw coal of size 300 mm max will be crushed to 25 mm size in Ring granulator type crushers ( 2 x 100%). Crushed coal will be either sent to Coal yard for storage (capacity to hold 30 days requirement) or sent to bunkers for firing. One no Stacker-cum-Reclaimer will be used to stack and reclaim the coal. Coal handling plant (CHP) will be consisting of 3 nos. truck tipplers (2W+1S) and 3 nos unloading hoppers for tipper trucks, crushing / stacking, reclaiming from the stockyard and conveying the same to steam generator bunkers using travelling tippers. 2 x 100% capacity conveyor system will be provided throughout. Inline Magnetic separators and metal detectors will be provided at Crusher house and bunker floor to separate magnetic and non-magnetic particles in coal. Belt weighers and coal samplers will be provided at appropriate locations to record the quality and quantity of coal received and utilized. When coal is required in the boiler bunkers and primary crusher is not in operation, coal will be reclaimed by the stacker / re-claimer and fed to boiler bunkers through secondary crusher. An emergency reclaim ground hopper will be provided to reclaim coal by dozers when stacker / re-claimer is not in operation. Required no. of dozers / mobile equipment will be provided. The stockpile of coal will have adequate storage for at least 7 days coal consumption. The stockpile will be provided with necessary fire hydrant system, compacting and dust suppression system. The capacity of the conveying system from of crusher up to the boiler bunkers onwards will be to meet the 24 hours MCR coal requirement of boiler in 12 hours. The conveyors will have 100% standby system. VIMTA Labs Limited, Hyderabad/Coimbatore 41

52 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Coal samplers and belt weigh scales will be provided in the junction tower prior to bunker feeding conveyor. Necessary inline magnetic separators and metal detectors will be provided in the conveyors feeding the crusher house. Bunker filling will be done by tipper conveyor arrangement. Bunker top will be sealed to have effective dust control and ventilation system in the bunker floor. Dust suppression system will be provided in all the transfer towers, crusher houses, and coal stockpile to minimize the air pollution problem. Necessary spray system arrangement will be provided in the coal stockpile. Bunker ventilation / dust extraction will be provided to extract the dust due to bunker filling operation. The coal stockpiles will be provided with ring main headers with hydrant valves located as per the statutory requirements for fire fighting operations. The complete coal handling system operation will be controlled from coal handling control room located near crusher house. The stacker / reclaimer will be operated from local station. A PLC based safety-interlocking system for coal-handling plant will be provided such that sequential starting/shut down of all the equipment due to trip condition of downstream conveying equipment is ensured. 2.9 Ash Handling System Ash handling, disposal and utilization As per the present comprehensive Guidelines of Ministry of Environment & Forests (MoEF) for fly ash utilization and disposal, all power stations should provide arrangements for dry ash collection and disposal (The Gazette of India: Extraordinary - Notification of Environment and Forests, New Delhi, dated 14 th September, 1999). In view of this, dry ash handling and disposal system has been considered for the existing & proposed unit. The design of ash handling system for the proposed units has been considered based on maximum 10% ash (max.) and 0.5% Sulphur (max.) in Coal. The following data has been considered for design of ash handling system: a. Hourly coal firing rate at MCR condition per unit for coal (maximum) 239 tons / hr b. Ash content in coal considered For the design of ash handling equipment 10% (maximum) For ash disposal area calculations 10% c. The system adopted for bottom ash removal will be dry system and for fly ash removal will be vacuum-cum-pressure type pneumatic system. d. The ash disposal will be in by means of trucks. e. As a contingency measure, wet ash system is also considered both for bottom ash and fly ash. VIMTA Labs Limited, Hyderabad/Coimbatore 42

53 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description f. Fly ash will be handled in dry and systems are designed for unloading in trucks to facilitate selling of fly ash. It will be ensured from the boiler manufacturer that the unburnt carbon content in the fly ash is limited to 3% by weight, so that the fly ash is acceptable to the cement manufacturers for using in their cement manufacturing process. The ash generated from the plant will be about 451 TPD (0.135 MTPA) considering ash content in the coal of 10%, and a plant load factor of 85%. Dry bottom ash handling system Shall allow the extraction of bottom ash coming from solid fuel fired boilers in completely dry manner. The bottom ash handling system shall consist of a completely robust extraction and conveying arrangement through steel belt conveyor suitable for handling dry bottom ash including clinkers. Arrangements shall be provided for cooling of bottom ash. The collected bottom ash shall be crushed in the crushers and then conveyed to the bottom ash silo. Suitable type and quantity of crushers shall be provided for crushing of bottom ash into smaller size for meeting requirements of pneumatic conveying up to bottom ash silo via buffer hopper. Bottom ash generation per unit will be calculated at 100 % PLF considering generation of bottom ash at 25% of total ash with worst coal. The Dry bottom ash from the buffer hopper shall be pneumatically conveyed to the bottom ash silo by positive pressure conveying system using transport air compressors. From bottom ash silo, suitable provision shall be provided for unloading the bottom ash into trucks or discharged for wet disposal; the slurry is led to the bottom ash slurry sump. From the sump, the slurry is transported to the dump area using ash slurry disposal pumps and pipelines. Fly Ash Handling System Ash collected in ECO hoppers shall be conveyed to the intermediate Fly ash hoppers from here the ash shall be conveyed to the fly ash silos. Vaccum Conveying Systems Fly ash collected in ESP, Air Preheater duct, and APH hoppers shall be conveyed from hoppers to buffer hoppers by vaccum system for onward pressure transportation to storage silos for collection in dry form. Each fly ash hopper shall be provided with manual chute isolation valve and ash intake valve below the hopper flange. Ash intake valves in the first three fields of the ESP shall be air assisted diffuser intake type valves. Gravity discharge intake valves shall be provided for the rest of the ESP fields and other APH and Duct hoppers. VIMTA Labs Limited, Hyderabad/Coimbatore 43

54 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description During System operation, the ash intake valve opens and fly ash shall fall under gravity into the ash conveying pipeline (branch pipeline) running below the fly ash hoppers. Each branch pipe of the conveying system shall be provided with an air intake valve thru which the atmospheric air shall enter the conveying line. Each branch line shall be laid along the flue gas path and four such pipelines emerging out of one ESP shall be connected to a header pipe, which shall be fed tom the bag filter separator cum buffer hopper. Each branch pipeline shall be separated from each other by cylinder operated isolation valve. RCC Silos The bottom ash and fly ash will be collected in the RCC silos. Individual silos for bottom ash & fly ash storage have been installed for each boiler. Capacity of fly ash silo is 791 m 3 and the capacity of bottom ash silo is 216 m 3. RCC silo will be for collecting bottom ash mixture from the boilers. The bottom ash storage silo will have 16 hours storage capacity. Fly ash silo will be for collecting fly ash. This silo also will have adequate storage capacity. The silos will be fitted with bag filters with the exhauster of the silo top to displace air from the silo Dry Ash Disposal Through Closed Tankers Dry Fly ash will be transported to the consumers in special construction closed tankers. The dry fly ash from fly ash silo bottom will be filled in the closed tankers with the help of motor operated retractable chutes to avoid fugitive ash going to the atmosphere and causing air pollution. Through Open Trucks (Conditioned Ash) In one of the openings at the bottom of each ash silo, pug mill (Ash conditioner) will be provided which will mix water in the dry ash mass to make it moist. Conditioned fly ash coming from the ash conditioner will be transported through open trucks to the consumers. Ash Utilization Non utilization of ash generated by thermal power station in India has been a big pollution threat as huge quantity of ash is generated every year. The Govt. of India has made guidelines to utilize the generated ash from the thermal power station. For this, entrepreneurs are being encouraged by giving relaxation at many fronts like supply of free dry ash, provision of land on concessional terms, power supply on the mutual agreed terms and conditions, etc. A list of areas for probable ash utilization is given below: VIMTA Labs Limited, Hyderabad/Coimbatore 44

55 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Use of fly ash in manufacturing Pozzolona cement - Use of fly ash for Pozzolona cement is quite prevalent in USA, Europe, Japan and other advanced countries. As per data available many Indian cement manufacturers are also using fly ash for manufacture of Pozzolona cement. The Govt. of India, in order to encourage use of fly ash in manufacture of Pozzolona cement, has introduced Indian Standard in this regard. This cement is being manufactured in India as per Indian Standard IS: 3812, Also possibilities for utilizing fly ash as per the following shall also be envisaged: a) Concrete blocks. b) Concrete c) Screed d) Refractory Concrete e) Ash brick f) Use in mine - stowing of underground mines. g) Use as railway/road embankment h) As waste land reclamation material i) Use as stabilization of soil for road underbed. Fuel Oil Handling System The steam generators of power station will be designed for 100% Coal firing. However, LDO and HFO will be required for start-ups, stabilization during low load. The fuel oil facilities will be common to both the units. Fuel Oil Requirement Light Diesel Oil (LDO) Heavy Fuel Oil (HFO) LDO and HFO requirement has been estimated based on 1.0 ml/kwhr (CERC norms), which works out to approximately 4000 kilo liters per year for the power station. a) Light Diesel Oil (LDO) storage tanks For storage of LDO, 2 nos. x 150 KL bulk LDO storage tanks has been provided. b) Fuel oil decanting/unloading facilities LDO will be brought in road tankers from the nearest oil terminal and will be unloaded in the storage tanks through unloading header and 2 nos. unloading pumps. c) LDO supply to the Steam Generation units Two nos. of LDO pumps (1 W + 1S) will be installed for meeting the requirement of LDO delivery to both the boiler units. Duplex filters at suction side and at discharge side of each pump shall be provide Adequate provision will be made in the design of piping system which will be laid overhead supported on shop columns. The oil delivery pressure will suit the burner requirement. VIMTA Labs Limited, Hyderabad/Coimbatore 45

56 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Heavy Oil Storage Tanks For storage of heavy oil, 2 nos. x 300 KL bulk storage tanks are provided. Fuel Oil Decanting/Unloading Facilities Heavy fuel oil will be brought in road tankers from the nearest oil terminal and will be unloaded in the storage tanks through unloading header and 2 nos. unloading pumps. Heavy Fuel Supply to the Steam Generation Units Four nos. of HFO pumps (2 W + 2S) will be installed for meeting the requirement of Heavy oil delivery to both the boiler units. Duplex filters at suction side and at discharge side of each pump shall be provided. Oil heaters will be provided in the pump discharge. Adequate provision will be made in the design of piping system which will be laid overhead supported on shop columns. The oil delivery pressure will suit the burner requirement. Ventilation System An elaborate ventilation system has been envisaged for the power house building, ESP control building and other areas like air compressor room, DM plant building, elevator machine rooms and various pump houses like ash water pump house, filter water pump house, etc. to achieve the followings: i) Dust-free comfortable working environment. ii) Scavenging out structural heat gain and heat load from various equipment, hot pipes, lighting etc., iii) Dilution of polluted air due to generation of obnoxious gaseous/aerosol contaminants like acid fumes, dusts etc., The following areas are proposed to be ventilated: Turbine building and tipper floor ESP control building Ash slurry pump house Air compressor rooms AC plant room DM plant building Miscellaneous rooms in powerhouse like cable spreader room, switch gear room, oil room, toilet, elevator m/c room etc. VIMTA Labs Limited, Hyderabad/Coimbatore 46

57 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description a) Power House Supply/exhaust ventilation: system with evaporative cooling has been recommended for the powerhouse building. Ambient air will be drawn through inertia filters, metallic panel filters, spray bank, moisture eliminator and will be supplied by means of centrifugal fan to power house through ducting and grilles to achieve proper distribution. The water sprayed will be re-circulated by means of centrifugal pumps, piping, valves and other accessories. This is about the supply system. 'Exhaust' system consists of axial flow roof exhaust fans with rain protection cowl hood, short duct work etc. Part of the supplied air will be exhausted and the rest will ex-filtrate through the various openings in the structure, preventing infiltration of dusty air. This arrangement also ensures more or less ambient dry bulb temperature inside power house. Various rooms in power house e.g. Cable spreader room, switchgear room etc. will be ventilated by means of transfer fans or by extending duct as required and found suitable. Coal tripper floors are proposed to be provided with exhaust system to eliminate building up to hazardous gases like carbon monoxide, methane etc. b) ESP Control Building (Excepting Control Room) For ventilation of this building, ambient air will be drawn through unitary air filtration unit compressing of fresh air intake Louvre, automatically cleanable nylon filter (with water spray) and moisture eliminator and. supplied to the space by means of centrifugal fan through ducting, grilles etc. The water for filter cleaning will be re-circulated by means of centrifugal pumps. In addition to filter cleaning, the water spray will have an evaporative cooling effect too. This will produce some cooling as an added advantage. The supplied air will be exhausted through wall mounted gravity operated to maintain an overpressure of 2-3 mm of WC to reduce dust. c) Other Buildings Other buildings like ash water pump house, air compressor room, etc., will be ventilated by means of dry system comprising of axial flow fan, dry filter wherever required, cowls, ducting etc., Inside dry bulb temperature will be higher than ambient by about 5 Degree centigrade. Fire dampers will be provided wherever there is electrical installation. Thermal Insulation Insulation will be provided wherever necessary to minimize heat losses from the equipment, piping and ducts and to ensure protection to personnel. Insulation will be held by adequate cleats, wire nets, jackets, etc. to avoid loosening. Insulation thickness will be so selected that the covering jacket surface temperature does not exceed the surrounding ambient temperature by more than 15 o C. The turbine proper will be spray insulated as recommended by the turbine supplier. VIMTA Labs Limited, Hyderabad/Coimbatore 47

58 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Painting All mechanical and electrical equipment including piping system and structures wil1 be painted with international standards / IS standard colour-code for ease of identification. The equipment exposed to marine environment will be painted / coated with suitable corrosion resistant paint such as polyurethane paint. Fire Protection System The firefighting system will be designed in conformity with the recommendations of the Tariff Advisory Committee of Insurance Association of India. While designing the fire protection systems for this power station its extreme ambient conditions need special attention. Codes and Standards of National Fire Protection Association (NFPA) will be followed, as applicable. The Power Plant is classified as Ordinary Hazard Occupancy as per TAC. Hence, the entire system will be designed accordingly. The different types of fire protection /detection system envisaged for the entire power plant are described below. Hydrant System for entire area of power plant High Velocity Water Spray System (HVWS) for generator transformer, Unit Auxiliary transformer, station transformer, and turbine lube oil canal pipe lines in main plant, Boiler burner front, diesel oil tank of DG set, main lube oil tank, clean and dirty lube oil tanks. Medium Velocity Water spray system - cable gallery / Cable spreader room, Coal conveyors, Transfer points and crusher house, F.O. pumping station and F.G. tanks Foam system for Fuel oil tanks. Portable extinguisher will be provided for Central Control room, Control equipment room and Computer rooms in the power house building. Portable and mobile fire extinguishers for entire plant Fire Tenders (minimum 2 Nos.) Fire Detection and Alarm system for all Central Control room, Control Equipment Room, battery rooms, all switchgear rooms / MCC rooms, and Computer rooms located in Power block area and in other auxiliary buildings. Necessary instruction and warning plates shall be provided all around All necessary facemasks, fire jackets, breathing and resuscitation apparatus and/or ether protection devices for optimal protection for the personnel. VIMTA Labs Limited, Hyderabad/Coimbatore 48

59 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Hydrant System The hydrant system consists of a large network of pipe, which will feed pressurized water, to a number of hydrant outdoor, water monitors and indoor landing valves with hose reel system. External hydrants will be located all around the periphery of buildings and internal hydrants will be provided at each landing floor of staircases through above ground main. Outdoor type fixed water monitors will be provided for ESP areas and other areas in the coal conveyors at locations where water cannot reach from hydrant system. Hose pipes of suitable length fitted with standard accessories like hose coupling, branch pipes and nozzles will be located in 'HOSE BOXES'. High Velocity Water Spray (HVWS) System The spray ring main header will cater water for the spray system. For water spray system piping network will be separate from the pump house. The HVWS system will be designed for automatic remote and manual emergency operation for the Generator Transformers, Unit Aux. Transformer and Station Transformer and remote manual operation for turbine lube oil canal pipe lines in main plant, Boiler burner front, and diesel oil Tank of DG set, main lube oil tank, clean and dirty lube oil tanks. Medium Velocity Water Spray (MVWS) System The medium velocity spray system will be provided for the cable gallery /Cable spreader room, Coal conveyors, Transfer points and crusher house, F.O. pumping station and F.O. tanks. Water required for this system will be.tapped off from HVWS/MVWS header. The fire in the cable gallery / Cable spreader room and coal conveyors will be detected by a detection system, which will give an electrical signal for the operation of the deluge valve. In the event of fire in zone, the deluge valve of corresponding zone and those of adjacent zone on either side will be opened. The MVWS system for fuel oil pump house will be designed considering the pump house as a single zone. A network of pipes with spray nozzles will be located near the roof of the pump house, which will be connected to a deluge valve. Manual MVWS system will be provided for L.D.O and H.F.O tanks. This system is provided for LDO and HFO storage tanks. The water for the foam system will be tapped from the Hydrant system. The system will consist of foam tank, level indicators, foam ejector, foam makers, fixed piping valves, etc. Portable and Trolley mounted fire Extinguishers Fire Extinguishers with suitable capacity, rating and medium such as water, CO2, foam, Dry Chemical powder (DCP) and with standard accessories and in adequate numbers as per TAC covering all the buildings in the power plant premises will be provided. VIMTA Labs Limited, Hyderabad/Coimbatore 49

60 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Fire Tender One no. Water Fire Tender as per IS: 950 Type-B. One no. Foam Tender as per IS Fire Water Reservoir The Plant will be provided with fire water from service I fire water reservoir of such volume have to satisfy the fire water demand of plant in the worst assumed scenarios as per TAC requirements. A dedicated storage of 2300m 3 of water is envisaged. Fire Water Pumps The fire water pump capacity and head will be designed as per the system requirement. The fire hydrant system will have dedicated 2 x 100% firewater main pumps of capacity 410m 3 /hr, 88MWC. The main fire pump will be motor driven and one standby diesel engine driven. A separate fire pumps including with one standby diesel engine driven pump will serve the HVWS/MVWS system. The standby pump of Hydrant system will also serve as standby for HVWS/MVWS system. The entire fire water network will be pressurized and maintained the hydro-pneumatic tank along with common jockey pumps and air compressors functions to make up the system leakage losses. All the main and standby pumps will be capable of operating at 150% flow with a head drop less than or equal to 65% of the operating head. The shutoff head of the pump will not be more than 140 % of operating head. Fire pumps will conform to IS: 5120 and will be certified by TAC as approved Fire pumps. Diesel Engine drive set The diesel engine will be of direct injection, multi-cylinder, water cooled, 4-stroke cycle and will have engine shaft power rating at least fifteen 15 % higher than the maximum power required at the pump shaft at rated speed. As the fire pumping unit is not required to run continuously for long period and operation will not be very frequent, special features will be built into the engine to allow it to start instantaneously against full load; even it has remained idle for long period. The engine will be able to start quickly from cold condition. The starting system will include a DC motor having high starting torque to overcome full engine compression. The engine will be provided with two sets of 24 volts heavy duty VRL and lead acid batteries. VIMTA Labs Limited, Hyderabad/Coimbatore 50

61 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description The diesel engine will have provision to start on auto / manual mode. The selector switch for the same will be provided in the control panel. The cooling water system for the diesel engine will be provided as per TAC requirement. The fuel storage tank will be provided as per the TAC requirement. Fire Detection and Alarm System Fire detection and alarm system provided for the entire plant area will be microprocessor based Intelligent Analog Addressable type. The system will consist of central monitoring station located in unit control room will be provided. The main fire alarm panel will be provided in the unit control room, one fire alarm and control panel in coal handling plant control room and repeater panel, which will be provided hi the fire station office Miscellaneous Auxiliaries Cranes, Hoists & Elevators Electric Overhead Traveling (EOT) cranes will be provided in Steam Turbine hall, raw water and firewater pump house, workshop, DG plant building etc. The cranes will be used for unloading of heavy equipment and also for erection and maintenance of equipment. The cranes will be designed to handle the heaviest piece in that area during maintenance. Monorail hosts of suitable capacity will be installed in the following areas. Fuel oil pump house DM plant Chlorination Plant Air heater ID fan & FD fan area Mills area Air compressor house / building Ash water pump house Ash recycle water pump house Stores One goods cum passenger elevator of about 2000 kg carrying capacity will be provided for boiler house and one goods cum passenger elevator of about 1000 kg carrying capacity will be provided for power house building. One passenger elevator of about 550 kg carrying capacity will be provided for the administrative building. One number of rack and pinion lift for chimney will be provided for handling passenger / goods. VIMTA Labs Limited, Hyderabad/Coimbatore 51

62 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Associated Facilities Repair Workshop For achieving higher availability of the plant some of the plant maintenance would have to be done at site following concept of unit exchange system for repair and maintenance. Under this system, the defective components would be replaced immediately by sound ones from the stores. Some of the defective components would thereafter be repaired in the site workshop and sent back to the stores. Following this System two types of activities namely maintenance and reconditioning would be physically separated thereby. Speeding-up maintenance activity In order to carry out the repair activities, it is proposed to provide the following shops a. Main workshop b. Instrument repair shop c. A repair shop for mobile equipment to be located near the coal storage yard d. Loco engine repair shade e. Motor vehicle repair shops Besides tools, tackle, gadgets, measuring instruments, testing equipment as required would be procured General Stores Both covered and open space would be required for storage of various material and equipment required for construction as well as operation and maintenance of the plant. While the construction stores would be temporary, the other stores would be permanent. Stores would broadly have the following divisions to house equipment and material of different categories Chemical Laboratory & Testing Facilities A fully equipped chemical laboratory adequate to carry out the tests and analyses required for the station would be provided in the Service Building of the station. The testing and calibration laboratories for Control &Instrumentation (C&I) and Relay-Metering instruments would also be housed in the same building. Necessary facilities including standard instruments for analyses or tests or calibrations of various items would be provided. VIMTA Labs Limited, Hyderabad/Coimbatore 52

63 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description 2.11 Sources of Pollution and Mitigation Measures The various types of pollution from a thermal power power plant are categorized under the following types: a) Air pollution b) Water pollution c) Sewage disposal d) Thermal pollution e) Noise pollution f) Pollution monitoring and surveillance systems Coal based thermal power plants are a major source of gaseous emissions. In addition, wastewater and solid waste will also be generated. The quantities and the composition of the gaseous, liquid and solid waste that are generated in a thermal power plant will be managed and treated such that their final disposal into the environment meets all the statutory requirements and the environmental impacts are mitigated Air Pollution Sources and Mitigation Measures The Air pollutants from the power plant are: a) Dust particulates from fly ash in flue gas b) Sulphur dioxide in flue gas c) Nitrogen oxides in flue gas d) Particulate Matter (PM) e) Coal dust particles during storage/handling The Indian Emission Regulations stipulate the limits for particulate matter emission for thermal power stations. The minimum stack height to be maintained to keep the Sulphur dioxide level in the ambient within the air quality standards. The stack height for the 60 MW & 135 units under consideration will be 145 metres (common stack). For the Independent 1 x 350 MW unit, separate stack (220 m) will be erected considering fuel characteristics. The dust content in the flue gas will be limited to 50 mg/nm 3 even with one of the fields of ESP is not in working condition. Providing specially designed burners reduce NO x emission from the steam generator. The maximum NO x emission from the unit will be as per the CPCB/SPCB norms by using low NO x burners in the firing system of the steam generator. As noted above, PM, SO 2 and NO x emission levels will meet the requirement of Indian Central Pollution Control Board (CPCB). For coal dust control, water spraying arrangement will be provided to spray water into each wagon prior to discharge. Dust generated at the wagon discharge points will be further suppressed by spraying chemical solution. VIMTA Labs Limited, Hyderabad/Coimbatore 53

64 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Crusher houses, junction towers, feed points below wagon discharge and emergency reclaim hoppers will be provided with wet scrubber type dust extraction system. Sprinklers will be provided all around the stockpile to suppress the dust generation and to wet the coal while compacting to minimize the dust nuisance. The expected air emissions are given in Table TABLE 2.12 STACK MONITORING DATA Particulars Stack #1 Stack #2 Material of Construction RCC RCC Stack attached to 1 x 60 MW & 1 x 350 MW 1 x 135 MW Stack height (m) Stack diameter (mm) approx Volume Flow Rate (m 3 /s) Velocity of flue gas (m/s) Temperature of flue gas ( C) Flue gas specific volume (kg/nm³) Fuel Consumption (kg/s) Sulphur content (% w/w) Emission rate NO x (g/s) Emission rate SO 2 (g/s) Emission rate PM (g/s) Mitigation Measures The mitigation measures proposed for the TPP are detailed below: 145 m & 220 m tall stacks for flue gas emission Space provision for retrofitting FGD (Flue Gas Desulfurization) systems High efficiency ESPs to reduce PM level in the exhaust gas to < 50 mg/nm³ Dust suppression and extraction system at handling plant area to control fugitive emission Greenbelt development in the plant and ash disposal areas A minimum water depth will be maintained in the ash dyke to prevent fugitive dust emission Use of bag filters at all transfer points Use of limestone to limit SO 2 emission High efficiency Electro Static Precipitator of 99.9% are provided for limiting PM concentration in the flue gas to less than 50 mg/nm³. The tall stack of 145 m & 220 m height based on maximum SO 2 concentration in the flue gas is provided for natural dispersion at high elevation so that ground level concentration are within acceptable limits The emission of NO x, is reduced by burning fuel at a lower temperature and shortening the throughput time of the fuel NO x is also controlled by operating at low excess air VIMTA Labs Limited, Hyderabad/Coimbatore 54

65 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description Fugitive Emissions All other dust sources are considered as secondary sources since they are not process implied. These dust sources may occur wherever relatively dry or dusty material is handled, conveyed, pumped or extracted. Water spray is being carried out to control fugitive dust due to wind. All the materials will be stored in a covered storage facilities Wastewater Generation and Mitigation Measures Steam generator blow down The salient characteristics of the blow down water from the point of view of pollution are the ph and temperature of water since suspended solids are negligible. The ph will be in the range of 9.5 to 10.3 and the temperature of the blow down water will be about 100 C since it is flashed in an atmospheric flash tank (IBD tank). It is proposed to lead steam generator blow down to cooling tanks and then sequentially to guard pond. The retained water will be RO treated to meet the CPCB norms and will be reused for boiler make-up. DM Plant Effluents Hydrochloric acid and caustic soda will be used as regenerants in the DM plant. The acid and alkali effluents during the regeneration process of the ion exchangers will be drained into an underground neutralizing pit. The effluent will be neutralized by the addition of either acid or alkali to achieve the required ph. The effluent will then be pumped to RO plant and reused for process. Effluent Disposal The following high TDS effluents water will be collected in a guard pond. Pressure sand filter back wash (TDS < 100) Effluent discharge from Neutralizing pit (TDS < 6000) Sewage Disposal Sewage from various buildings in power plant area will be conveyed through separate drains to septic tanks. The effluent from septic tank will be disposed in soil by providing dispersion trenches. There will be no ground pollution because of leaching. Sludge will be removed occasionally and will be disposed of as land fill at suitable places. The waste water generated from proposed project is given in Table VIMTA Labs Limited, Hyderabad/Coimbatore 55

66 Sr. No. Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description TABLE-2.13 WASTE WATER GENERATION FROM THE POWER PLANT Units Water Requirement (KLD) Loses/ Uses Waste Water Generated Usage/ Disposal 1 Boiler Makeup Reuse for process 2 Potable Water Greenbelt maintenance 3 DM Plant Reuse for process Total The total wastewater generated from the plant after the proposed expansion will be KLD. Boiler blow down (173.0 KLD) & DM plant regeneration wastewater (31.0 KLD) generated after the proposed expansion will be treated in 2-stage RO plant. Available treated effluent ( KLD) will be re-used in the process. RO reject (43.84 KLD) will be used for ash quenching & coal dust suppression. Domestic sewage (12.8 KLD) will be treated in the existing sewage treatment plant itself. Treated domestic sewage will be utilized for greenbelt maintenance. Thus, the plant will operate on zero liquid discharge concept even after the proposed expansion Solid Waste Generation and Mitigation Measures Ash is the main solid waste generated in the coal based thermal power plant. Major portion of the ash will be utilized by supplying to potential users. Efforts will be made to utilize 100% fly ash as per the Fly Ash Notification, 1999 and as amended later. The ash which is not lifted by the potential users will be disposed of in the ash dyke using High Concentration Slurry Disposal (HCSD) method. In this method of ash disposal, the slurry is highly viscous and non-newtonian fluid requiring less water compared to conventional low concentration slurry disposal. The ash dyke will be provided with trenches to collect the storm water during rainy days. Greenbelt will be provided enveloping the ash dyke to arrest the fugitive dust emissions. Ash dyke will also be provided with HDPE liner to prevent leaching of contaminants to groundwater. The quantities of solid waste expected the plant is given in Table VIMTA Labs Limited, Hyderabad/Coimbatore 56

67 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description TABLE 2.14 SOLID WASTE GENERATION AND DISPOSAL Ash generation Sr. Upon Mode of Power Generation Existing No. expansion Disposal (TPD) (TPD) 1. 1 x 60 MW Sold to Cement 2. 1 x 135 MW manufacturers 3. 1 x 350 MW Total Noise Pollution and Mitigation Measures Capacity of fly ash silo: 791 m 3 Capacity of bottom ash silo: 216 m 3 The major noise generating sources in the power plant are boiler, coal crushing, material handling area, and water pumps. The noise levels at 1 m away from these sources will be maintained at less than 85-dB (A) in compliance with the statutory requirements. All equipment in the power plant will be designed/operated to have a noise level not exceeding 85 to 90 db(a) as per the requirement of Occupational Safety and Health Administration Standard (OSHA). As per this standard, protection from noise is required when sound levels exceed those in given below when measured on the A scale at slow response on a standard sound level meter. TABLE 2.15 NOISE LEVEL EXPOSURE LIMITS Duration per day (hrs.) Sound level in db(a) In general, the following measures will be adopted for noise pollution control. Technical measures Administrative measures Personal protection measures VIMTA Labs Limited, Hyderabad/Coimbatore 57

68 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 2 Project Description In thermal power plants high pressure boilers, exhausters, turbines and leaking air/ steam pipelines are the primary sources of noise pollution. The following technical measures will be taken to overcome these noises. Continuous vigilance in high pressure air/steam pipelines for leakages and once noticed, immediate plugging of the leakage reduces plugging them, thus reducing the noise at the source. Providing acoustic enclosures / barriers for the turbines. Providing silencers at inlet / outlet of the high pressure equipment like DG set, compressors, fans etc., Regular checking of vibration level of high speed machines and taking necessary steps to mitigate the same. In areas such as turbine floor, compressed air station and pump houses, soundproof enclosures will be provided for the operators. In the boiler plant, there are various noise polluting sources such as boilers and high pressure pipelines where technical measures will not be practically effective. In such cases, the following administrative measures are proposed. Workers will be assigned rotational duties to minimize noise exposure time. Medical check-up of all workers will be done at regular interval for any noise related health problems and if any such problem is detected they will be assigned alternative duty. Besides all the above measures all workers exposed to high noise will be provided with personal protective devices such as ear plugs and ear muffs. Workers will be educated about the benefits of the protective devices and encouraged to use them Environmental Laboratory To evaluate the physico-chemico properties of source emission /waste water discharge and to establish the ambient pollution level during power plant operation, as desired by the Ministry of Environment, Forest & Climate Change (MoEFCC), New Delhi, and State Pollution Control Board (SPCB), an environmental laboratory has been considered for monitoring/ testing of different pollutants, Gas, liquid & solids, generated from the plant. List of equipment/instrument pertaining to Environmental pollution monitoring will be provided during detailed engineering. VIMTA Labs Limited, Hyderabad/Coimbatore 58

69 district, Tamilnadu Chapter 3 Description of the environment 3.0 DESCRIPTION OF THE ENVIRONMENT 3.1 Introduction This chapter illustrates the description of the existing environmental status of the study area with reference to the prominent environmental attributes. As per the EIA guidelines, the study area has been divided into core zone and buffer zone which is about 10 km radius from the boundary of the existing & the proposed site. The existing environmental setting is considered to adjudge the baseline environmental conditions, which are described with respect to climate, hydrogeological aspects, atmospheric conditions, water quality, soil quality, vegetation pattern, ecology and socio-economic profiles of people and land use. The objective of this section is to define the present environmental status, which would help in assessing the environmental impacts due to the proposed expansion activities. This report incorporates the baseline data generated through primary surveys for three months from 1 st May 2014 to 31 st July 2014 representing pre-monsoon season. 3.2 Methodology Appropriate methodologies have been followed in developing the EIA/EMP report. The methodology adopted for the study is outlined below: Conducting reconnaissance surveys for knowing the study area; and Selecting sampling locations for conducting various environment baseline studies. The sampling locations have been selected on the basis of the following: Predominant wind directions recorded by the India Meteorological Department (IMD) Meenambakkam, Chennai observatory; Existing topography; Drainage pattern and location of existing surface water bodies like lakes/ponds, rivers and streams; Location of villages/towns/sensitive areas; and Areas, which represent baseline conditions. The field observations have been used to: Assess the positive and negative impacts due to the proposed expansion activity; and Suggest appropriate mitigation measures for negating the adverse environmental impacts, if any; and Suggesting post-project monitoring requirements and suitable mechanism for it. Vimta Labs Limited, Hyderabad/Coimbatore 59

70 district, Tamilnadu Chapter 3 Description of the environment 3.3 Geology & hydrogeology Central Ground Water Board (CGWB) has carried out extensive geological and hydro-geological surveys for the Thiruvallur district Administrative Details Tiruvallur district is having administrative divisions of 8 taluks, 14 blocks, 539 Panchayats and 805 villages Basin and sub-basin The district is part of the composite east flowing river basin having Araniar- Korataliar and Cooum sub basins Drainage Araniyar, Korattalayar, Cooum, Nagari and Nandhi are the important rivers. The drainage pattern, in general, is dendritic. All the rivers are seasonal and carry substantial flows during monsoon period. Korattaliar river water is supplied to Cholavaram and Red Hill tanks by constructing an Anicut at Vellore Tambarambakkam. After filling a number of tanks on its further course, the river empties into the Ennore creek a few kilometres north of Chennai. The Cooum river, flowing across the southern part of the district, has its origin in the surplus waters of the Cooum tank in Tiruvallur taluk and also receives the surplus waters of a number of tanks. It feeds the Chembarambakkam tank through a channel. It finally drains into the Bay of Bengal. The chief irrigation sources in the area are the tanks, wells and tube wells. Canal irrigation is highest in Minjur block followed by Sholavaram, Pallipattu, R.K.Pet, Poondi, Gummidipoondi and Ellapuram blocks Rainfall and climate The district receives the rain under the influence of both southwest and northeast monsoons. Most of the precipitation occurs in the form of cyclonic storms caused due to the depressions in Bay of Bengal chiefly during Northeast monsoon period. The southwest monsoon rainfall is highly erratic and summer rains are negligible. Rainfall data analysis shows that the normal annual rainfall varies from 950mm to 1150mm. It is minimum around Chengam (982.1mm) in the south eastern part of the district. It gradually increases towards west and a maximum around Wandavasi (1117.1mm) is noticed. The district enjoys a tropical climate. The period from April to June is generally hot and dry. The weather is pleasant during the period from November to January. Usually mornings are more humid than afternoons. The relative humidity varies between 65 and 85% in the mornings while in the afternoon it varies between 40 and 70%. The annual mean minimum and maximum temperature are 24.3 and 32.9 C respectively. The day time heat is oppressive and the temperature is as high as 41.2 C. The lowest temperature recorded is of the order of 18.1 C. Vimta Labs Limited, Hyderabad/Coimbatore 60

71 district, Tamilnadu Chapter 3 Description of the environment Geomorphology and soil types Soil The prominent geomorphic units identified in the district through interpretation of Satellite imagery are 1) Alluvial Plain, 2) Old River Courses 3) Coastal plains 4) Shallow & deep buried Pediments, 5) Pediments and 6) Structural Hills. The elevation of the area ranges from 183 m AMSL in the west to sea level in the east. Four cycles of erosion gave rise to a complex assemblage of fluvial, estuarine and marine deposits. The major part of the area is characterized by an undulating topography with innumerable depressions which are used as irrigation tanks. The coastal tract is marked by three beach terraces with broad inter-terrace depressions. The coastal plains display a fairly lower level or gently rolling surface and only slightly elevated above the local water surfaces or rivers. The straight trend of the coastal tract is resultant of development of vast alluvial plains. There are a number of dunes in the coastal tract. Soil in the area have been classified into i) Red soil ii) Black soil iii) Alluvial soil iv) colluvial soil. The major part is covered by Red soil of red sandy/clay loam type. Ferrugineous red soils are also seen at places. Black soils are deep to very deep and generally occur in the depressions adjacent to hilly areas, in the western part. Alluvial soils occur along the river courses and eastern part of the coastal areas. Sandy coastal alluvium (arenaceous soil) are seen all along the sea coast as a narrow belt Ground water scenario Hydrogeology The district is underlain by both porous and fissured formations. The important aquifer systems in the district are constituted by i) unconsolidated & semiconsolidated formations and ii) weathered, fissured and fractured crystalline rocks. The porous formations in the district include sandstones and clays of Jurassic age (Upper Gondwana), marine sediments of Cretaceous age, Sandstones of Tertiary age and Recent alluvial formations. As the Gondwana formations are wellcompacted and poorly jointed, the movement of ground water in these formations is mostly restricted to shallow levels. Ground water occurs under phreatic to semi-confined conditions in the inter-granular pore spaces in sands and sandstones and the bedding planes and thin fractures in shales. In the area underlain by Cretaceous sediments, ground water development is rather poor due to the rugged nature of the terrain and the poor quality of the formation water. Quaternary formations comprising mainly sands, clays and gravels are confined to major drainage courses in the district. The maximum thickness of alluvium is 30.0 m. whereas the average thickness is about 15.0 m. Vimta Labs Limited, Hyderabad/Coimbatore 61

72 district, Tamilnadu Chapter 3 Description of the environment Ground water occurs under phreatic to semi-confined conditions in these formations and is being developed by means of dug wells and filter points. Alluvium, which forms a good aquifer system along the Araniyar and Korattalaiyar river bed, is one of the major sources of water supply to the urban areas of Chennai city and also the industrial units. Ground water generally occurs under phreatic conditions in the weathered mantle and under semi-confined conditions in the fissured and fractured zones at deeper levels. The thickness of weathered zone in the district is in the range of 2 to 12 m. The depth of the wells ranged from 8.00 to m bgl. The yield of large diameter wells tapping the weathered mantle of crystalline rocks ranges from 100 to 500 lpm and are able to sustain pumping for 2 to 6 hours per day. The yield of bore wells drilled down to a depth of 50 to 60 m ranges from 20 to 400 lpm. The yield of successful bore wells drilled down to a depth of 150 m bgl during the ground water exploration programme of Central Ground Water Board ranged from 1.2 to 7.6 lpm. The depth to water level in the district varied between m bgl during pre-monsoon (May 2006) and m bgl during post monsoon (Jan 2007). The seasonal fluctuation shows a rise between 0.28 and 4.80 m bgl. The piezometric head varied between 2.20 to m bgl (May 2006) during premonsoon and 2.72 to 8.55 m bgl during post monsoon. Ground water resources The ground water resources have been computed jointly by Central Ground Water Board and State Ground & Surface Water Resources and Development Centre (PWD, WRO, Government of Tamil Nadu) as on 31 st March The salient features of the computations are furnished in Table-3.1. Vimta Labs Limited, Hyderabad/Coimbatore 62

73 Block Rapid Environmental Impact Assessment for the proposed augmentation & district, Tamilnadu Chapter 3 Description of the environment Net Groundwater Availability (M.Cu.m) Existing Gross Draft for Irrigation (M.Cu.m) TABLE-3.1 GROUND WATER RESOURCES Existing Gross Draft for Domestic and industrial water supply (M.Cu.m) Existing Gross Draft for all uses (M.Cu.m) Allocation for Domestic and Industrial Requirement supply upto next 25 years (2029) (M.Cu.m) Net groundwatre Availability for future Irriation Development (M.Cu.m) Stage of Groundwater Development (%) Category of Block Ellapuram Over Exploited Gummudipoondi Safe Kadambathur Critical Madhavaram Safe Minjur Over Exploited Pallipattu Over Exploited Poonamalee Critical Poondi Safe R.K.Pet Over Exploited Sholavaram Semi Critical Thiruvalankadu Over Exploited Tiruttani Over Exploited Tiruvallur Semi Critical Villivakkam Safe District Total Ground water in phreatic aquifers in Tiruvallur district, in general, is colourless, odourless and slightly alkaline in nature. The specific electrical conductance of ground water in phreatic zone (in MicroSeimens at 25 o C) during May 2006 was in the range of 480 to 2360 in the district. It is between 750 and 2250 µs/cm at 25 o C in the major part of the district. Conductance below 750 µs/cm have been observed in ground water in parts of Gummidipundi, Minjur, Sholavaram and Puzhal blocks, whereas conductance exceeding 2250 µs/cm have been observed in part of Tiruvelangadu block. It is observed that the ground water is suitable for drinking and domestic uses in respect of all the constituents except total hardness and Nitrate in more than 90 percent of samples analysed. Total Hardness as CaCO 3 is observed to be in excess of permissible limits in about 36 percent of samples analysed whereas Nitrate is found in excess of 45 mg/l in about 32 percent samples. The incidence of high total hardness is attributed to the composition of lithounits constituting the aquifers in the district, whereas the Nitrate pollution is most likely due to the use of pesticides and fertilizers for agriculture. With regard to irrigation suitability based on specific electrical conductance and Sodium Adsorption Ratio (SAR), it is observed that ground water in the phreatic zone may cause high to very high salinity hazard and medium to high alkali hazard when used for irrigation. Proper soil management strategies are to be adopted in the major part of the district while using ground water for irrigation. Vimta Labs Limited, Hyderabad/Coimbatore 63

74 district, Tamilnadu Chapter 3 Description of the environment Status of Ground Water Development The estimation of groundwater resources for the district has shown that 6 blocks are over exploited and 2 blocks are under critical category. The shallow alluvial aquifers along Korattalaiyar and Araniyar rivers serve as an important source of drinking water for Chennai Metropolitan area and 5 well fields have been constructed in Tiruvallur district for the purpose. The well fields have a combined yield of MCM/year. Dug wells are the most common ground water abstraction structures used for irrigation in the district. The yield of dug wells range from < 50 to 200 m 3 /day in weathered crystalline rocks, 20 to 100 m 3 /day in Gondwana formations and upto 400 m3/day in Recent alluvial formations along major drainage courses. The dug wells in hard rock terrain tapping the entire weathered residuum are capable of yielding 6-7 lps, requiring the installation of 5 HP centrifugal pumps for extraction of ground water. Vimta Labs Limited, Hyderabad/Coimbatore 64

75 BAY OF BENGAL Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur district, Tamilnadu Chapter 3 Description of the environment GUMMIDIPOONDI ANDHRA PRADESH PALLIPATTU MINJUR UTHUKOTTAI RK PET THIRUTTANI VELLORE THIRUVILANGADU POONDI THIRUVALLUR VILLIVAKKAM SHOLAVARAM CHENNAI POONAMALEE KANCHIPURAM FIGURE-3.1 HYDROGEOLOGY OF THIRUVALLUR DISTRICT Vimta Labs Limited, Hyderabad/Coimbatore 65

76 3.4 Land Use Studies Rapid Environmental Impact Assessment for the proposed augmentation & district, Tamilnadu Chapter 3 Description of the environment Studies on land use aspects of eco-system play an important role in identifying sensitive issues and taking appropriate actions by maintaining Ecological Homeostasis for development of the region Objectives The objectives of land use studies are: Methodology To determine the existing land use pattern in the study area; To analyze the impacts on land use in the study area; and To give recommendations for optimizing the future land use pattern vis-a-vis proposed expansion activity in the study area and its associated impacts. The land use pattern of the study area has been studied by analyzing the available secondary data such as the District Primary Census Handbook of Thiruvallur District. The land use is classified into four types - viz. forests, area under cultivation, cultivable waste and the area not available for cultivation. The land under cultivation is further sub-divided into two types viz. irrigated and un-irrigated Land Use Pattern in Study Area Based on Satellite imagery Methodology Information of land use and land cover is important for many planning and management activities concerning the surface of the earth (Agarwal and Garg, 2000). Land use refers to man's activities on land, which are directly related to land (Anderson et al., 1976). The land use and the land cover determine the infiltration capacity. Barren surfaces are poor retainers of water as compared to grasslands and forests, which not only hold water for longer periods on the surface, but at the same time allow it to percolate down. The terms land use and land cover (LULC) are often used to describe maps that provide information about the types of features found on the earth s surface (land cover) and the human activity that is associated with them (land use). These are important parameters for number of environmental related development projects associated with inland and coastal areas. It is necessary to have information on existing land use / land cover but also the capability to monitor the dynamics of land use resulting out of changing demands. Satellite remote sensing is being used for determining different types of land use classes as it provides a means of assessing a large area with limited time and resources. However satellite images do not record land cover details directly and they are measured based on the solar energy reflected from each area on the land. Vimta Labs Limited, Hyderabad/Coimbatore 66

77 district, Tamilnadu Chapter 3 Description of the environment The amount of multi spectral energy in multi wavelengths depends on the type of material at the earth s surface and the objective is to associate particular land cover with each of these reflected energies, which is achieved using either visual or digital interpretation. In the present study the task is to study in detail the land use and land cover in and around the project site respect to the development of the plant. The study envisages different LULC around the plant area and the procedure adopted is as below. Remote sensing satellite imageries were collected and interpreted for the 10-km radius study area for analyzing the Land use pattern of the study area. Based on the satellite data, Land use/ Land cover maps have been prepared. Scale of mapping Considering the user defined scale of mapping, 1:50000 IRS-P6, LISS-III data on 1:50000 scale was used for Land use / Land cover mapping of 10 km radius for proposed expansion activity. The description of the land use categories for 10 km radius and the statistics are given for core and buffer zones separately. Vimta Labs Limited, Hyderabad/Coimbatore 67

78 district, Tamilnadu Chapter 3 Description of the environment FIGURE 3.2 FLOW CHART SHOWING METHODOLOGY OF LANDUSE MAPPING Vimta Labs Limited, Hyderabad/Coimbatore 68

79 district, Tamilnadu Chapter 3 Description of the environment Interpretation Technique Standard on screen visual interpretation procedure was followed. The various Land use / Land cover classes interpreted along with the SOI topographical maps during the initial rapid reconnaissance of the study area. The physiognomic expressions conceived by image elements of color, tone, texture, size, shape, pattern, shadow, location and associated features are used to interpret the FCC imagery. Image interpretation keys were developed for each of the LU/LC classes in terms of image elements. March 2009 FCC imagery (Digital data) of the study area was interpreted for the relevant land use classes. On screen visual interpretation coupled with supervised image classification techniques are used to prepare the land use classification. i. Digitisation of the study area (10 km radius from the plant site) from the topo maps ii. Satellite Data Selection: In the present study the IRS P6 satellite image with path row for the topo map of 57P-7. have been procured and interpreted using the ERDAS imaging software adopting the necessary interpretation techniques. iii. Satellite data interpretation and vectorisation of the resulting units iv. Adopting the available guidelines from manual of LULC mapping using Satellite imagery (NRSA, 1989) v. Field checking and ground truth validation vi. Composition of final LULC map The LULC Classification has been done at three levels where level -1 being the broad classification about the land covers that is Built-up land, agriculture land, waste land, wet lands, and water bodies. These are followed by level II where built-up land is divided into towns/cities as well villages. The Agriculture land is divided into different classes such as cropland, Fallow, Plantation, while wastelands are broadly divided into, Land with scrub and without Scrub and Mining and Industrial wasteland. The wetlands are classified into inland wetlands, coastal wetlands and islands. The water bodies are classified further into River/stream, Canal, Tanks and bay. In the present study level II classification has been undertaken. The satellite imagery of 10 km radius from the project site is presented in Figure-3.3. Field Verification Field verification involved collection, verification and record of the different surface features that create specific spectral signatures / image expressions on FCC. In the study area, doubtful areas identified in course of interpretation of imagery is systematically listed and transferred on to the corresponding SOI topographical maps for ground verification. In addition to these, traverse routes were planned with reference to SOI topographical maps to verify interpreted LU/LC classes in such a manner that all the different classes are covered by at least 5 sampling areas, evenly distributed in the area. Vimta Labs Limited, Hyderabad/Coimbatore 69

80 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur district, Tamilnadu Chapter 3 Description of the environment PROPOSED AUGMENTATION & EXPANSION OF EXISTING THERMAL POWER PLANT AT GUMMIDIPOONDI, THIRUVALLUR DISTRICT, TAMILNADU FIGURE 3.3 SATELLITE IMAGERY OF THE STUDY AREA Vimta Labs Limited, Hyderabad/Coimbatore 70

81 district, Tamilnadu Chapter 3 Description of the environment Ground truth details involving LU/LC classes and other ancillary information about crop growth stage, exposed soils, landform, nature and type of land degradation are recorded and the different land use classes are taken. Description of the land use / land cover classes Built-up land It is defined as an area of human settlements composed of houses, commercial complex, transport, communication lines, utilities, services, places of worships, recreational areas, industries etc. Depending upon the nature and type of utilities and size of habitations, residential areas can be aggregated into villages, towns and cities. All the man-made construction covering land belongs to this category. Agricultural land This category includes the land utilized for crops, vegetables, fodder and fruits. Existing cropland and current fallows are included in this category. It is described as an area under agricultural tree crops, planted adopting certain agricultural management techniques. Wasteland Wastelands are the degraded or under-utilized lands most of which could be brought under productive use with proper soil and water management practices. Wasteland results from various environmental and human factors. Land with or without Scrub The land, which is outside the forest boundary and not utilized for cultivation. Land with or without scrub usually associated with shallow, stony, rocky otherwise non-arable lands. Water bodies The category comprises area of surface water, either impounded in the form of ponds, reservoirs or flowing as streams, rivers and canals. River cater channel is inland waterways used for irrigation and for flood control. The land use map of the study area based on satellite imagery is presented in Figure-3.4. The land use analyses show that the area is of predominantly Plantation followed by Crop land in the core and buffer zones of the study area. It is noticed since there is no industrial development in and around the project site, there may not have any direct impact on the existing land use and soil. However, it is generally agreed that as the total volume of transport activity may increase due to the development leading to negative externalities like pollution and congestion. Some environmental damage may be acceptable if transport activity generates positive net benefits to society. Vimta Labs Limited, Hyderabad/Coimbatore 71

82 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur district, Tamilnadu Chapter 3 Description of the environment PROPOSED AUGMENTATION & EXPANSION OF EXISTING THERMAL POWER PLANT AT GUMMIDIPOONDI, THIRUVALLUR DISTRICT, TAMILNADU FIGURE 3.4 LANDUSE OF THE STUDY AREA Vimta Labs Limited, Hyderabad/Coimbatore 72

83 3.5 Meteorology Rapid Environmental Impact Assessment for the proposed augmentation & District, Tamilnadu Chapter 3 Description of the environment The meteorological data recorded during the monitoring period is very useful for proper interpretation of the baseline information as well as for input prediction models for air quality dispersion. Historical data on meteorological parameters will also play an important role in identifying the general meteorological regime of the region. The year may broadly be divided into four seasons: Winter season : December to February Pre-monsoon season : March to May Monsoon season : June to September Post-monsoon season : October to November Methodology The methodology adopted for monitoring surface observations is as per the standard norms laid down by Bureau of Indian Standards (IS:8829) and India Meteorological Department (IMD). On-site monitoring was undertaken for various meteorological variables in order to generate the site-specific data. The generated data is then compared with the meteorological data generated by IMD. Methodology of Data Generation The automatic meteorological instrument was installed on top of the admin building at the plant premises to record wind speed, direction, relative humidity and temperature. Cloud cover is recorded by visual observation. Rainfall is monitored by rain gauge. Hourly average, maximum, and minimum values of wind speed, direction, temperature, relative humidity and rainfall have been recorded continuously at this station. Continuous recording meteorological instrument [Make: Dynalab, Pune (Model No.WDL1002] has been used for recording the met data. The sensitivity of the equipment is given in Table-3.2. TABLE-3.2 SENSITIVITY OF METEOROLOGY MONITORING EQUIPMENT Sr. No. Sensor Sensitivity 1 Wind Speed Sensor ± 0.02 m/s 2 Wind Direction Sensor ± 3 degrees 3 Temperature Sensor ± 0.2 o C Sources of Information Secondary information on meteorological conditions has been collected from the nearest IMD station at Chennai Airport. Vimta Labs Limited, Hyderabad/Coimbatore 73

84 District, Tamilnadu Chapter 3 Description of the environment India Meteorological Department has been monitoring surface observations at Chennai since Pressure, temperature, relative humidity, rainfall, wind speed and direction are measured twice a day viz., at 0830 and 1730 hr. The wind speed and direction data of IMD, Chennai has been obtained for the past available 10 years. The data for the remaining parameters has been collected for the last 10 years and processed Synthesis of Data on Climatic Conditions Analysis of the data Recorded at IMD Chennai Temperature The winter season starts from January and continues till the end of February. January is the coldest month with the mean daily maximum temperature at 33.3 C with the mean daily minimum temperature at 17.0 C. Both the day and night temperatures increase rapidly during the onset of Pre-monsoon season. During Premonsoon the mean maximum temperature (May) is observed at 43.4 C with the mean minimum temperature at 21.6 C. The mean maximum temperature in the Monsoon season was observed to be 42.8 C whereas the mean minimum temperature was observed to be 21.2 C. By end of September with the onset of Northeast monsoon (October), day temperatures decrease slightly with the mean maximum temperature at 35.9 C with the mean minimum temperature at 22.4 C. The monthly variations of temperatures are presented in Table-3.3. Relative Humidity The air is generally very humid in the region especially during monsoon when the average relative humidity is observed around 67% with a maximum and minimum of 100% and 35% respectively. In the pre-monsoon period the relative humidity is 63%. During the pre-monsoon season the mean maximum humidity is observed at 100%, with the mean minimum humidity at 39% in the month of May and April respectively. During winter season the humidity is found to be in line with the values recorded during the Pre-monsoon season. The mean maximum humidity recorded during winter season, which is the driest part of year with an average of 66% relative humidity. The mean maximum relative humidity is observed to be 100% with mean minimum humidity at 38%. The monthly mean variations in relative humidity are presented in Table-3.3. Atmospheric Pressure The station level maximum and minimum atmospheric pressure levels are recorded during the winter and monsoon seasons. The maximum pressure observed is in the range of to mb, with the maximum pressure ( Mb) occurring during the winter season, in the month of January. The minimum pressure observed is in the range of to Mb, with the minimum pressure (999.9-Mb) occurring during the pre-monsoon season in the month of June. The average pressure levels in all other months are found to be in the range of to mb. The monthly variations in the pressure levels are presented in Table Vimta Labs Limited, Hyderabad/Coimbatore 74

85 Rainfall Rapid Environmental Impact Assessment for the proposed augmentation & District, Tamilnadu Chapter 3 Description of the environment It is observed that the north-east monsoon is more predominant than the southwest monsoon. The southwest monsoon generally sets in during the last week of May. About 30% of the rainfall is received during the southwest monsoon. The rainfall gradually increases after September (and reaches maximum rainfall is recorded in the month of November). The area experiences maximum rainfall (308.0 mm) in the month of November. The Northeast monsoon rain occurs between October to December and contribute to the rainfall by about 60% of the total rainfall. Monthly variations in the rainfall for past available 10 years are given in Table Cloud Cover Generally light clouds are observed during winter mornings. During pre-monsoon and the post-monsoon evenings the skies are either clear or lightly clouded. But in post-monsoon mornings as well as monsoon mornings heavy clouds are commonly observed. Whereas in the evening time the skies are light to moderately clouded throughout the year. Special Weather Phenomena Thunderstorms are frequent in pre-monsoon, post monsoon and early North-east monsoon seasons. Occasional squalls occur in association with thunderstorms in the later pre-monsoon season. On an average three to four severe cyclonic storms form in the Bay of Bengal, (mostly from April to June in pre-monsoon and September to December in postmonsoon season). It is observed that cyclonic storms are five times more frequent in the Bay of Bengal than in Arabian Sea. This is quite evident from the hazards that the eastern coast faces year after year compared to west coast. The seasonal frequencies of cyclones in East Coast of India during are given in Table Wind Speed/Direction The wind rose for the study period representing pre-monsoon, monsoon, postmonsoon and winter season along with annual wind rose are shown in Figure- 3.5 (A), (B) & (C) and presented in Table-3.5. Vimta Labs Limited, Hyderabad/Coimbatore 75

86 District, Tamilnadu Chapter 3 Description of the environment TABLE-3.3 CLIMATOLOGICAL DATA - IMD, CHENNAI Month Temperature ( 0 Relative Atmospheric C) Rainfall Humidity (%) Pressure (Mb) (mm) Max Min Avg January February March April May June July August September October November December TABLE-3.4 SEASONAL FREQUENCIES OF CYCLONES IN EAST COAST OF INDIA Month Seasonal Frequency January 4 February 0 March 2 April 11 May 15 June 32 July 33 August 27 September 23 October 40 November 40 December 22 Total 249 TABLE-3.5 SUMMARY OF WIND PATTERN IMD, CHENNAI Season First predominant winds Second predominant winds Calm condition in % Premonsoon S (29.0) S (37.5) SSW (17.5) SSW (24.9) Monsoon SSW (17.3) SSW (20.3) SW (16.9) S (18.1) Post NNE (17.0) E (15.0) N (15.5) NE (14.0) monsoon Winter NE (16.7) S (14.6) NNE (14.0) E (11.6) Annual SSW (12.9) S (18.9) SW (10.0) SSW (14.2) Vimta Labs Limited, Hyderabad/Coimbatore 76

87 District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.5 (A) WINDROSE FOR PRE MONSOON & MONSOON SEASON-IMD, CHENNAI Vimta Labs Limited, Hyderabad/Coimbatore 77

88 District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.5 (B) WINDROSE FOR POST MONSOON & WINTER SEASON-IMD, CHENNAI Vimta Labs Limited, Hyderabad/Coimbatore 78

89 District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.5 (C) ANNUAL WINDROSE -IMD, CHENNAI Vimta Labs Limited, Hyderabad/Coimbatore 79

90 District, Tamilnadu Chapter 3 Description of the environment Analysis of Meteorological Data Recorded at Project Site The meteorological data recorded at the plant site during the study period (1 st May, 2014 to 31 st July, 2014) is presented in Table-3.6. TABLE-3.6 SUMMARY OF THE METEOROLOGICAL DATA AT SITE Month Temperature ( o C) Humidity (%) Total Rainfall Max Min Max Min (mm) May June July Temperature It was observed that the temperature at the plant site during study period ranged from 22.0 o C to 43.0 o C. The monthly variations in the temperatures are presented in Table-3.6. Humidity During the period of observation, the humidity ranged from 18.0% to 100.0%. Cloud Cover Mostly clear skies were observed during the study period. Wind Speed and Direction The windrose for the study period representing pre-monsoon season is shown in Figure-3.7. A review of the windrose diagram shows that predominant winds are mostly from West (18.5%) followed by South (14.6%). Calm conditions were recorded for 3.34%. Vimta Labs Limited, Hyderabad/Coimbatore 80

91 District, Tamilnadu Chapter 3 Description of the environment WIND ROSE PLOT: WIND ROSE PLOT: Station # name: 03 Existing plant site of ARS Metals Pvt. Ltd. DISPLAY: DISPLAY: Wind Speed Wind speed Direction Direction (blowing (Blowing from) from) NORTH 20% 16% 12% 8% 2.91% 1.31% 4% WEST 3.78% EAST 18.49% 11.94% 7.86% 10.77% 9.61% 6.99% 10.63% 14.56% SOUTH WIND SPEED (m/s) >= Calms: 3.34% COMMENTS: COMMENTS: DATA PERIOD: DATA PERIOD: START DATE: 1/05/ :00 END Start DATE: Date: 31/07/2014 1/1/ :00 23:00 End Date: 1/30/ :00 COMPANY NAME: ARS METALS PVT. LTD. MODELER: VIMTA LABS LIMITED CALM WINDS: 3.34% % PREDOMINANT TOTAL COUNT: WIND DIRECTION: WEST 719 hrs. ( o o ) AVG. WIND SPEED: SPEED: 3.57 m/s DATE: 2014 AUGUST 25 8/25/2014 PROJECT NO.: 002/AMBA/ARS WRPLOT View - Lakes Environmental Software FIGURE-3.6 SITE SPECIFIC WINDROSE (MAY JULY 2014) Vimta Labs Limited, Hyderabad/Coimbatore 81

92 3.6 Air Quality Rapid Environmental Impact Assessment for the proposed augmentation & District, Tamilnadu Chapter 3 Description of the environment The ambient air quality with respect to the study zone of 10-km radius around the project site forms the baseline information. The various sources of air pollution in the region are industries and vehicular traffic. The prime objective of the baseline air quality study was to assess the existing air quality of the area. The study area represents mostly rural environment. This section describes the selection of sampling locations, methodology adopted for sampling, analytical techniques and frequency of sampling Methodology adopted for Air Quality Survey Selection of Sampling Locations The baseline status of the ambient air quality has been assessed through a scientifically designed ambient air quality-monitoring network. The design of monitoring network in the air quality surveillance program has been based on the following considerations: Meteorological conditions on synoptic scale; Topography of the study area; Representatives of regional background air quality for obtaining baseline status; Representatives of likely impact areas. Ambient Air Quality Monitoring (AAQM) stations were set up at eight locations with due consideration to the above mentioned points. Table-3.7 gives the details of environmental setting around each monitoring station. The location of the selected stations with reference to the project site is given in the same table and shown in Figure-3.7. TABLE-3.7 DETAILS OF AMBIENT AIR QUALITY MONITORING LOCATIONS Station Code Name of the Station Distance & direction w.r.t project site (km) AAQ 1 Plant site --- AAQ 2 Gangadoddi 5.8 km, East AAQ 3 Valaimadu 4.1 km, NE AAQ 4 Edur 5.1 km, North AAQ 5 Surapundi 3.6 km, NW AAQ 6 Muttureddikandigai 4.4 km, SE AAQ 7 Amirtamangalam 2.7 km, SW AAQ 8 Vaniyamalli 3.5 km, WSW Vimta Labs Limited, Hyderabad/Coimbatore 82

93 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.7 AIR QUALITY SAMPLING LOCATIONS Vimta Labs Limited, Hyderabad/Coimbatore 83

94 District, Tamilnadu Chapter 3 Description of the environment Frequency and Parameters for Sampling The following frequency has been adopted for sampling: Ambient air quality monitoring has been carried out with a frequency of two days per week at all locations for study period from 1 st May 2014 to 31 st July The baseline data of air environment is generated for the following parameters: Particulate Matter (PM 10 ); Particulate Matter (PM 2.5 ); Sulphur dioxide (SO 2 ); Nitrogen dioxide (NO 2 ); Carbon monoxide (CO); Ozone (O 3 ); Ammonia (NH 3 ); Lead (Pb); Arsenic (As); Nickel (Ni); Benzene (C 6 H 6 ); and Benzo(a)Pyrene Duration of Sampling The sampling duration for PM 10, PM 2.5, SO 2, NO 2, Pb, NH 3, C 6 H 6, BaP, As and Ni was twenty-four hourly continuous samples per day and CO & O 3 was sampled for 8 hrs continuous thrice a day. This is to allow a comparison with the present revised standards mentioned in the latest Gazette notification of the Central Pollution Control Board (CPCB) (November 16, 2009). TABLE-3.8 MONITORED PARAMETERS AND FREQUENCY OF SAMPLING PM 10 PM 2.5 Parameters Sulphur dioxide (SO 2 ) Oxides of Nitrogen (NO X ) Ozone (O 3 ) Ammonia (NH 3 ) Lead (Pb) Arsenic (As) Nickel (Ni) Carbon Monoxide (CO) Benzene (C 6 H 6 ) Benzo(a)Pyrene Mercury (Hg) Sampling Frequency 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 08 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 08 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly sample twice a week for three months 24 hourly samples twice a week for three months Method of Analysis The air samples were analyzed as per standard methods specified by Central Pollution Control Board (CPCB), IS: 5184 and American Public Health Association (APHA). Vimta Labs Limited, Hyderabad/Coimbatore 84

95 District, Tamilnadu Chapter 3 Description of the environment Instruments used for Sampling Respirable Dust Samplers (APM-460 model) have been used for monitoring Suspended Particulate Matter (SPM), Respirable Particulate Matter (PM 10 ) and gaseous pollutants like SO 2 and NO 2. Fine Dust Samplers of Polltech instruments were used for monitoring PM 2.5. Glass tubes were deployed for collection of grab samples of carbon monoxide. Gas Chromatography techniques have been used for the estimation of CO Instruments used for Analysis The make and model of the instruments used for analysis of the samples collected during the field monitoring are given in Table-3.9. TABLE-3.9 INSTRUMENTS USED FOR ANALYSIS OF SAMPLES Sr. No. Instrument Name Parameters 1 Spectrophotometer SO 2, NO x, O 3 2 Electronic Balance TSPM, PM 10, PM Gas Chromatograph with FID, pfpd, ECD CO Sampling and Analytical Techniques The techniques used for ambient air quality monitoring and minimum detectable levels are given in Table Sr. No. TABLE-3.10 TECHNIQUES USED FOR AMBIENT AIR QUALITY MONITORING Parameters Test method Minimum detectable limit 5.0 g/m 3 1 PM 10 Gravimetric (Respirable dust sampling / High volume sampling) 2 PM 2.5 Gravimetric (FRM method / Low volume 2.0 g/m 3 sampling) 3 Sulphur dioxide (SO 2) Modified West & Gaeke method 4.0 g/m 3 4 Nitrogen dioxide (NO 2) Sodium Arsenite method 9.0 g/m 3 5 Ozone (O 3) Spectrophotometric method 2.0 g/m 3 6 Ammonia (NH 3) Indo-phenol blue method 20.0 g/m 3 7 Lead (Pb) AAS/ICP-MS method after sampling on EPM filter paper 0.05 ng/m 3 8 Arsenic (As) AAS/ICP-MS method after sampling on EPM 0.2 ng/m 3 filter paper 9 Nickel (Ni) AAS/ICP-MS method after sampling on EPM filter paper 0.10 ng/m 3 10 Carbon Monoxide (CO) Adsorption and extraction followed by GC-MS analysis 12.5 g/m 3 11 Benzene (C 6H 6) Adsorption and desorption followed by GC-MS analysis 1.0 ng/m 3 12 Benzo (a) Pyrene (BaP) Solvent extraction followed by GC-MS 1.0 ng/m 3 Vimta Labs Limited, Hyderabad/Coimbatore 85

96 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment Presentation of Primary Data Various statistical parameters like 98 th percentile, average, maximum and minimum values have been computed from the observed raw data for all the AAQ monitoring stations. The summary of these results is presented in Table-3.11 TABLE-3.11 SUMMARY OF AMBIENT AIR QUALITY RESULTS PM 10 ( g/m 3 ) PM 2.5 (µg/m 3 ) SO 2 ( g/m 3 ) NO 2 ( g/m 3 ) CO ( g/m 3 ) Parameters AAQ-1 AAQ-2 AAQ-3 AAQ-4 AAQ-5 AAQ-6 AAQ-7 AAQ-8 Maximum Minimum Average %tile Maximum Minimum Average %tile Maximum Minimum Average %tile Maximum Minimum Average %tile Maximum Minimum Average %tile Note: Ozone (O 3 ), Ammonia (NH 3 ), Lead (Pb), Arsenic (As), Nickel (Ni), Benzene (C 6 H 6 ) and Benzo(a)Pyrene (BaP) are found to exist below Detectable Limit. Vimta Labs Limited, Hyderabad/Coimbatore 86

97 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment Observations of Primary Data The three months ambient air quality data are given as Annexure 9. PM 10 : The maximum and minimum concentrations for PM 10 were recorded as 83.1 g/m 3 and 33.4 g/m 3 respectively. The maximum concentration was recorded at Plant Site (AAQ1) and the minimum concentration was recorded at Vaniyamalli (AAQ8). The average values were observed to be in the range of 35.9 and 78.3 g/m 3. PM 2.5 : The maximum and minimum concentrations for PM 2.5 were recorded as 27.4 g/m 3 and 11.0 g/m 3 respectively. The maximum concentration was recorded at Plant Site (AAQ1) and the minimum concentration was recorded at Vaniyamalli (AAQ8). The average values were observed to be in the range of 11.8 and 25.8 g/m 3. SO 2 : The maximum and minimum SO 2 concentrations were recorded as 26.9 g/m 3 and 6.4 g/m 3. The maximum concentration was recorded at Plant Site (AAQ1) and the minimum concentration was recorded at Edur (AAQ4). The average values were observed to be in the range of 7.4 and 22.5 g/m 3. NO 2 : The maximum concentration of 33.2 g/m 3 for NO 2 was recorded at Plant Site (AAQ1) and minimum of 9.3 g/m 3 observed at Surapundi (AAQ5). The average concentrations were ranged between 11.0 and 30.6 g/m 3. CO: The maximum concentration of 343 g/m 3 was recorded at Plant site (AAQ1) and minimum of 141 g/m 3 observed at Edur (AAQ4). The average concentrations were ranged between 153 and 282 g/m 3. The concentrations of PM 10, PM 2.5, SO 2, NO X and CO are observed to be well within the standards prescribed by Central Pollution Control Board (CPCB) for Industrial, Rural, Residential and other area. Other parameters including Ozone (O 3 ), Ammonia (NH 3 ), Lead (Pb), Arsenic (As), Nickel (Ni), Benzene (C 6 H 6 ), Benzo(a)Pyrene (BaP) & Mercury (Hg) are found to exist below detectable limits. Vimta Labs Limited, Hyderabad/Coimbatore 87

98 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment 3.7 Noise Level Survey The physical description of sound concerns its loudness as a function of frequency. Noise in general is sound which is composed of many frequency components of various loudness distributed over the audible frequency range. Various noise scales have been introduced to describe, in a single number, the response of an average human to a complex sound made up of various frequencies at different loudness levels. The most common and universally accepted scale is the A weighted Scale which is measured as db (A). This is more suitable for audible range of 20 Hz to 20,000 Hz. The scale has been designed to weigh various components of noise according to the response of a human ear. The impact of noise sources on surrounding community depends on: Characteristics of noise sources (instantaneous, intermittent or continuous in nature). It can be observed that steady noise is not as annoying as one which is continuously varying in loudness; The time of day at which noise occurs, for example high noise levels at night in residential areas are not acceptable because of sleep disturbance; and The location of the noise source, with respect to noise sensitive land use, which determines the loudness and period of exposure. The environmental impact of noise can have several effects varying from Noise Induced Hearing Loss (NIHL) to annoyance depending on loudness of noise. The environmental impact assessment of noise due to construction activity, and vehicular traffic can be undertaken by taking into consideration various factors like potential damage to hearing, physiological responses, annoyance and general community responses. Noise monitoring has been undertaken for 24-hr duration at each location Identification of Sampling Locations A preliminary reconnaissance survey has been undertaken to identify the major noise generating sources in the area. Noise at different noise generating sources has been identified based on the activities in the village area, ambient noise due to industries and traffic and the noise at sensitive areas like hospitals and schools. The noise monitoring has been conducted for determination of noise levels at ten locations in the study area. The environmental settings of each noise monitoring location is given in Table-3.12 and depicted in Figure Method of Monitoring Sound Pressure Level (SPL) measurements were measured at all locations; one reading for every hour was taken for 24 hours. The day noise levels have been monitored during 6 am to 10 pm and night levels during 10 pm to 6 am at all the monitoring locations within the study area. Vimta Labs Limited, Hyderabad/Coimbatore 88

99 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment Instrument Used for Monitoring Noise levels were measured using integrated sound level meter manufactured by Quest Technologies, USA (Model No.2900). The integrating sound level meter is an integrating/ logging type with Octave filter attachment (model OB-100) with frequency range of 31.5 to Hz. This instrument is capable of measuring the Sound Pressure Level (SPL), L eq and octave band frequency analysis. Location Code TABLE 3.12 DETAILS OF NOISE MONITORING LOCATIONS Location (Village) Distance & direction w.r.t plant site (km) Zone N1 Plant site --- Industrial N2 Melpakkam 2.5 km, North Residential N3 Gopalreddikandigai 2.1 km, NE Residential N4 Bodireddikandigai 3.5 km, East Residential N5 Billakuppam 2.3 km, SE Residential N6 Amirthamangalam 2.5 km, SSW Industrial N7 Vaniyamalli 3.4 km, West Residential N8 Ramachandrapuram 3.1 km, NW Residential N9 Palayapalayam 1.8 km, East Residential N10 Gumpuahintala 3.1 km, North Residential Parameters Measured During Monitoring For noise levels measured over a given period of time interval, it is possible to describe important features of noise using statistical quantities. This is calculated using the percent of the time certain noise levels are exceeding the time interval. The notation for the statistical quantities of noise levels are described below: L 10 is the noise level exceeded 10 per cent of the time; L 50 is the noise level exceeded 50 per cent of the time ; and L 90 is the noise level exceeded 90 per cent of the time. Equivalent Sound Pressure Level (L eq ): The Leq is the equivalent continuous sound level which is equivalent to the same sound energy as the actual fluctuating sound measured in the same period. This is necessary because sound from noise source often fluctuates widely during a given period of time. This is calculated from the following equation: (L 10 - L 90 ) 2 L eq = L L day is defined as the equivalent noise level measured over a period of time during day (6 am to 10 pm). L night is defined as the equivalent noise level measured over a period of time during night (10 pm to 6 am). A noise rating developed by Environmental protection Agency (EPA) for specification of community noise from all the sources is the Day- Night Sound Level, (L dn ). Vimta Labs Limited, Hyderabad/Coimbatore 89

100 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.8 NOISE QUALITY MONITORING LOCATIONS Vimta Labs Limited, Hyderabad/Coimbatore 90

101 district, Tamilnadu Chapter 3 Description of the environment Day-Night Sound Level (L dn ): The noise rating developed for community noise from all sources is the Day-Night Sound Level (L dn ). It is similar to a 24 hr equivalent sound level except that during night time period (10 pm to 6 am) a 10 db (A) weighting penalty is added to the instantaneous sound level before computing the 24 hr average. This night time penalty is added to account for the fact that noise during night when people usually sleep is judged as more annoying than the same noise during the day time. The L dn for a given location in a community may be calculated from the hourly L eq 's, by the following equation. L dn = 10 log {1/24[16(10 Ld/10 ) + 8 (10 (Ln+10)/10 )]} Where L d is the equivalent sound level during the daytime (6 am to 10 pm) and L n is the equivalent sound level during the nighttime (10 pm to 6 am) Presentation of Results The statistical analysis is done for measured noise levels at ten locations for once during study period. The parameters are analyzed for L day, L night, and L dn. These results are tabulated in Table TABLE-3.13 NOISE LEVELS IN THE STUDY AREA Code Location L 10 L 50 L 90 L EQ L day L night L dn N1 Plant site N2 Melpakkam N3 Gopalreddikandigai N4 Bodireddikandigai N5 Billakuppam N6 Amirthamangalam N7 Vaniyamalli N8 Ramachandrapuram N9 Palayapalayam N10 Gumpuahintala Vimta Labs Limited, Hyderabad/Coimbatore 91

102 district, Tamilnadu Chapter 3 Description of the environment 3.8 Soil characteristics It is essential to determine the potentiality of soil in the area and to identify the impacts of urbanization on soil quality. Accordingly, the soil quality assessment has been carried out Data Generation The sampling locations have been identified with the following objectives: To determine the baseline soil characteristics of the study area; To determine the impact of proposed expansion activity on soil characteristics; and To determine the impact on soils more importantly from agricultural productivity point of view. Eight locations within 10-km radius of the plant boundary were selected for soil sampling. At all location, soil samples were collected from three different depths viz. 30 cm, 60 cm and 90 cm below the surface and are homogenized. This is in line with IS: 2720 and Methods of Soil Analysis, Part-1, 2 nd edition, 1986 of (American Society for Agronomy and Soil Science Society of America). The homogenized samples were analyzed for physical and chemical characteristics. The soil samples were collected during pre-monsoon season. The samples have been analyzed as per the established scientific methods for physico-chemical parameters. The heavy metals have been analyzed by using Atomic Absorption Spectrophotometer and Inductive Coupled Plasma Analyzer. The methodology adopted for each parameter is described in Table TABLE-3.14 ANALYTICAL TECHNIQUES FOR SOIL ANALYSIS Parameter Method (ASTM Number) Grain size distribution Sieve analysis (D ) Textural classification Chart developed by Public Roads Administration Bulk density Sand replacement, core cutter Sodium absorption ratio Flame colorimetric (D ) ph ph meter (D ) Electrical conductivity Conductivity meter (D ) Nitrogen Kjeldahl distillation (D ) Phosphorus Molybdenum blue, colorimetric (D ) Potassium Flame photometric (D ) Copper AAS (D ) Iron AAS (D ) Zinc AAS (D ) Boron Surcumin, colorimetric (D ) Chlorides Argentometric (D Rev 85) Vimta Labs Limited, Hyderabad/Coimbatore 92

103 district, Tamilnadu Chapter 3 Description of the environment The details of the soil sampling locations are given in Table-3.15 and shown in Figure-3.9. Code No. TABLE-3.15 DETAILS OF SOIL SAMPLING LOCATIONS Location Distance & direction w.r.t. plant site (Km) S 1 Plant site --- S 2 Melpakkam 2.1 km, NNW S 3 Gopalreddikandigai 1.9 km, NE S 4 Bodireddikandigai 2.9 km, East S 5 Billakuppam 1.8 km, SE S 6 Amirthamangalam 2.5 km, SSW S 7 Vaniyamalli 3.1 km, West S 8 Ramachandrapuram 2.8 km, NW Vimta Labs Limited, Hyderabad/Coimbatore 93

104 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.9 SOIL SAMPLING LOCATIONS Vimta Labs Limited, Hyderabad/Coimbatore 94

105 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment Baseline Soil Status The soil characteristics are shown in Table The results are compared with standard soil classification given in Table TABLE-3.16 SOIL ANALYSIS RESULTS Sr. No. Parameter UOM S1 S2 S3 S4 S5 S6 S7 S8 1 ph (1:5 Aq.Extract) Conductivity (1:5 Aq.Extract) S/cm Texture ---- Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay Sandy clay 4 Sand % Silt % Clay % Bulk Density mg/cc Exchangeable Calcium as Ca mg/kg Exchangeable Magnesium as Mg g/kg Exchangeable Sodium as Na mg/kg Available Potassium as K Kg/ha Available Phosphorous as P Kg/ha Available Nitrogen as N Kg/ha Organic Matter % Organic Carbon % Water Soluble Chloride as Cl mg/kg Water Soluble Sulphate as SO4 mg/kg Sodium Absorption Ratio Aluminium % Total Iron % Manganese mg/kg Boron mg/kg Zinc mg/kg It has been observed that the texture of soil is sandy clay in the study area. It has been observed that the ph of the soil ranged from 7.4 to 7.9. The electrical conductivity was observed to be in the range of µmhos/cm. Vimta Labs Limited, Hyderabad/Coimbatore 95

106 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment TABLE-3.17 STANDARD SOIL CLASSIFICATION Sr. No. Soil Test Classification 1 ph <4.5 Extremely acidic Very strongly acidic moderately acidic slightly acidic Neutral slightly alkaline moderately alkaline strongly alkaline 9.01 very strongly alkaline 2 Salinity Electrical Conductivity (mmhos/cm) (1 ppm = 640 mmho/cm) Upto 1.00 Average harmful to germination harmful to crops (sensitive to salts) 3 Organic Carbon Upto 0.2: very less : less medium, : on an average sufficient : sufficient >1.0 more than sufficient 4 Nitrogen (Kg/ha) Upto 50 very less less good Better >300 sufficient 5 Phosphorus (Kg/ha) Upto 15 very less less medium, on an average sufficient sufficient >80 more than sufficient 6 Potash (Kg/ha) very less less medium average better >360 more than sufficient Source: Handbook of Agriculture, ICAR, New Delhi Vimta Labs Limited, Hyderabad/Coimbatore 96

107 3.9 Water Quality Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment Selected water quality parameters of ground water and surface water resources within the study area has been studied for assessing the water environment and evaluate anticipated impact of the proposed expansion project. Understanding the water quality is essential in preparation of Environmental Impact Assessment and to identify critical issues with a view to suggest appropriate mitigation measures for implementation. The purpose of this study is to: Assess the water quality characteristics for critical parameters; Evaluate the impacts on agricultural productivity, habitat conditions, recreational resources and aesthetics in the vicinity; and Prediction of impact on water quality by this project and related activities. The information required has been collected through primary surveys and secondary sources Methodology Reconnaissance survey was undertaken and monitoring locations were finalized based on: Drainage pattern; Location of residential areas representing different activities/likely impact areas; and Likely areas, which can represent baseline conditions. Water sources covering 10-km radial distance were examined for physico-chemical, heavy metals and bacteriological parameters in order to assess the effect of industrial and other activities on water. The samples were collected and analyzed as per the procedures specified in 'Standard Methods for the Examination of Water and wastewater' published by American Public Health Association (APHA). Samples for chemical analysis were collected in polyethylene carboys. Samples collected for metal content were acidified with 1 ml HNO 3. Samples for bacteriological analysis were collected in sterilized glass bottles. Selected physicochemical and bacteriological parameters have been analyzed for projecting the existing water quality status in the study area. Parameters like temperature, Dissolved Oxygen (DO), free Chlorine and ph were analyzed at the time of sample collection Water Sampling Locations Water samples were collected from 6 ground water and 2 surface water-sampling locations. These samples were taken as grab samples and were analyzed for various parameters to be compared with the standards for drinking water as per IS:10500 (2012). The water sampling locations are listed below in Table-3.18 and are depicted in Figure Vimta Labs Limited, Hyderabad/Coimbatore 97

108 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment Presentation of Results TABLE-3.18 DETAILS OF WATER SAMPLING LOCATIONS Code Location Distance w.r.t. Project Site (km) Ground water GW1 Plant site --- GW2 Pappankuppam 3.0 km, East GW3 Billakuppam 2.3 km, SE GW4 Amirthamangalam 2.5 km, SSW GW5 Iguvarpalayam 2.0 km, NW GW6 Gopalreddikandigai 2.2 km, NE Surface water SW1 Chithoornatham pond 1.0 km, West SW2 Arani river 7.7 km, SW Ground Water Quality The results of the parameters analyzed for the 6 Ground water samples are presented in Table-3.19 and are compared with the standards for drinking water as per IS: (2012). Vimta Labs Limited, Hyderabad/Coimbatore 98

109 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.10 WATER SAMPLING LOCATIONS Vimta Labs Limited, Hyderabad/Coimbatore 99

110 District, Tamilnadu Chapter 3 Description of the environment TABLE 3.19 GROUND WATER QUALITY Sr. IS:10500 Parameter Units No. Limits GW1 GW2 GW3 GW4 GW5 GW6 1 ph to Colour Hazen 5 (15) < < Odour - UO Un-objectionable 4 Conductivity us/cm $ Taste - Ag Agreeable 6 Turbidity NTU 1 (5) Total hardness as mg/l 200 (600) CaCO 3 8 Total Dissolved solids mg/l 500 (2000) Chlorides as Cl mg/l 250 (1000) Residual free mg/l 0.2 Min <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 Chlorine 11 Fluoride as F mg/l 1.0 (1.5) Calcium as Ca mg/l 75 (200) Magnesium as Mg mg/l 30 (100) Sulphates as SO4 mg/l 200 (400) Nitrates as NO3 mg/l Phenolics as C 6H 5OH mg/l <0.001 <0.001 <0.001 <0.001 <0.001 < Cyanide as CN mg/l 0.05 <0.02 <0.02 <0.02 <0.02 <0.02 < Alkalinity as CaCO 3 mg/l 200 (600) Boron mg/l Sodium as Na mg/l $ Potassium as K mg/l $ Iron as Fe mg/l 0.3 <0.01 < Copper as Cu mg/l 0.05 <0.01 <0.01 <0.01 <0.01 < Manganese as Mn mg/l Aluminium as Al mg/l Chromium as Cr +6 mg/l 0.05 <0.05 <0.05 <0.05 <0.05 <0.05 < Cadmium as Cd mg/l 0.01 <0.01 <0.01 <0.01 <0.01 < Selenium as Se mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Arsenic as As mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Lead as Pb mg/l 0.05 <0.01 <0.01 <0.01 <0.01 <0.01 < Zinc as Zn mg/l 5 (15) 0.01 < Mercury as Hg mg/l <0.001 <0.001 <0.001 <0.001 <0.001 < Anionic detergents as mg/l 0.2 <0.2 <0.2 <0.2 <0.2 <0.2 <0.2 MBAS 34 Mineral oil mg/l 0.01 <0.01 <0.01 <0.01 <0.01 <0.01 < Pesticides mg/l Absent Absent Absent Absent Absent Absent Absent 36 E. coli - Absent Absent Absent Absent Absent Absent absent 37 Total Coliforms MPN/ <2 <2 <2 <2 <2 <2 U.O.: Un-objectionable $: Not specified NR No Relaxation The analysis results indicate that the ph ranges in between 7.4 to 7.8, which is well within the specified standard of 6.5 to 8.5. The Total Dissolved Solids (TDS) concentration is found to be ranging in between 223 to 414 mg/l. Total hardness was observed to be ranging from 190 to 350 mg/l. The Chlorides and Nitrates are found ranging from mg/l and mg/l. Potassium found ranging in between 1.3 to 8.5 mg/l. The Heavy metals are found to be below detectable limits. Vimta Labs Limited, Hyderabad/Coimbatore 100

111 District, Tamilnadu Chapter 3 Description of the environment Surface Water Quality The results of the parameters analyzed for the surface water samples are presented in Table TABLE 3.20 SURFACE WATER QUALITY Sr. No. Parameter Unit IS:10500 Limits SW1 SW2 1. ph (NR) Colour (Hazen) Hazen 5(15) <1 <1 3 Taste - Agreeable Ag Ag 4 Odour - UO U.O U.O 5 Conductivity ( s/cm) µs/cm $ Turbidity (NTU) NTU 1(5) Total Dissolved Solids mg/l 500 (2000) Total Hardness as CaCO 3 mg/l 200 (600) Total Alkalinity mg/l 200 (600) Calcium as Ca 2+ mg/l 75 (200) Magnesium as Mg 2+ mg/l 30 (100) Residual Chlorine mg/l 0.2 Min <0.2 < Boron mg/l Chloride as Cl - mg/l 250 (1000) Sulphate as SO 2+ 4 mg/l 200 (400) Fluorides as F mg/l 1.0 (1.5) Nitrate as NO 3 mg/l 45 (NR) Sodium as Na + mg/l $ Potassium as K + mg/l $ Phenolic Compounds mg/l (0.002) <0.001 < Cyanides mg/l 0.05 (NR) <0.02 < Anionic Detergents mg/l 0.2 (0.1) <0.1 < Mineral Oil mg/l 0.01 (0.03) <0.01 < Cadmium as Cd mg/l 0.01 (NR) <0.01 < Arsenic as As mg/l 0.01 (NR) <0.01 < Copper as Cu mg/l 0.05 (1.5) Lead as Pb mg/l 0.05 (NR) <0.01 < Manganse as Mn mg/l 0.1 (0.3) Iron as Fe mg/l 0.3 (1.0) Chromium as Cr+6 mg/l 0.05 (NR) <0.05 < Selenium as Se mg/l 0.01 (NR) <0.01 < Zinc as Zn mg/l 5 (15) Aluminium as Al mg/l 0.03 (0.2) <0.01 < Mercury as Hg mg/l (NR) <0.001 < Pesticides mg/l Absent Absent Absent 36 E. Coli - Absent Absent Absent 37 Total Coliforms MPN/100 ml 10 Absent Absent U.O. : Un-objectionable $ : Not specified NR No Relaxation The analysis results indicate that the ph value at SW1 & SW2 was found to exist as 8.1 & 7.1 respectively. The Total Dissolved Solids (TDS) concentration was found as 652 & 745. Vimta Labs Limited, Hyderabad/Coimbatore 101

112 District, Tamilnadu Chapter 3 Description of the environment 3.10 Ecology and Biodiversity Introduction Ecological evaluation aims at developing and applying methodologies to assess the relevance of an area for nature conservation. As such, it is to support the assessment of the impact of a proposed development by providing guidance on how to describe the ecological features within the area affected, how to value them, and how to predict the value losses caused by the development. The evaluation of the ecological significance of an area can be undertaken from different perspectives and consequently with different objectives. One of such perspectives focuses on the conservation of the biological diversity or biodiversity. Among the human activities that pose the highest threat to the conservation of biodiversity are the developmental projects in particular. Such projects represent artificial elements that cut through the landscape and interfere with the natural habitat and its conditions by emissions that may be solid, liquid and or gaseous. This in turn influences the abundance and distribution of plant and animal species, i.e., the biodiversity of the areas impacted. Most of the background data needs to be acquired from the governmental agencies or the scientific literature. This information is typically complemented by field visit, site surveys and sample collection. The description of the actual ecological assessment provided by the ecological baseline study serves to set a reference for the subsequent impact analysis. Moreover, it helps decision-makers and EIA reviewers to become familiar with the environmental features and the needs of the study area Objectives of the Study The present study was undertaken with the following objectives to assess both terrestrial and aquatic habitats of the study area: To assess the nature and distribution of vegetation in and around the existing project site. To assess the fauna in the study area; To understand the ecology of the water bodies; To ascertain the migratory routes of fauna, presence of breeding grounds and sensitive habitats in the study area, if any; To assess the presence of protected areas in the study area; To review the information from secondary sources and discuss the issues of concern with the relevant authority and stakeholders; Impact prediction based on primary and secondary data sources to formulate mitigation measures. Vimta Labs Limited, Hyderabad/Coimbatore 102

113 District, Tamilnadu Chapter 3 Description of the environment Methodology To achieve the above objectives a detailed study of the area was undertaken with the existing site as its centre. The different methods adopted were as follows: Generation of primary data by undertaking systematic ecological studies in the study area; Primary data collection for flora through random sampling method for trees, shrubs and herbs from the selected locations to know the vegetation cover qualitatively. To spot the fauna in the study area and also to identify the fauna by secondary indicators such as pugmarks, scats, fecal pallets, calls and other signs. For ecological information, the secondary sources such as local officials, villagers and other stakeholders were interviewed. Sourcing secondary data with respect to the study area from published literature. The list of Terrestrial and Aquatic sampling locations in the study area is presented in Table-3.21 and shown in Figure TABLE-3.21 LIST OF ECOLOGICAL SAMPLING LOCATIONS Code Name of the Locations Distance from Plant Site (Km) Direction w.r.t. Proposed Plant Site Terrestrial sampling locations TE-1 Manali R.F. Near Manali village 5.9 SSW TE-2 Near Siruvadu village 6.7 W TE-3 Near Nemalur village 6.6 W TE-4 Near kondamanallur 6.2 NNW Aquatic sampling locations AE-1 Near Arani village 8.8 SSE AE-2 Near Arigattura village 9.7 SE Vimta Labs Limited, Hyderabad/Coimbatore 103

114 District, Tamilnadu Chapter 3 Description of the environment FIGURE-3.11 ECOLOGICAL SAMPLING LOCATIONS Vimta Labs Limited, Hyderabad/Coimbatore 104

115 District, Tamilnadu Chapter 3 Description of the environment General Ecology of the Study Area The area is a degraded scrub land intermixed with agriculture fields. There is one reserved or protected forest in the study area. The region is an urbanized area with developmental activities that include industries, stone quarries, railway lines and roads. Some of the area is covered with agricultural fields as well as fruit trees cultivations. Small patches were noted of open scrublands forming pockets of degraded vegetation. Most of the horticultural activity is dominated by coconut and banana gardens Forest Blocks The forest area comes under broad category of Tropical semi evergreen forest of subgroup Sothern tropical semi evergreen forests. The nearest forest block is about 5.6 km from plant site on south west direction. The main composition of trees in forest blocks are mainly comprised of Azadiractha indica Ficus bengalensis, ficus religiosa, phenix spp,opuntia, Emblica officinalis, ziziphus jujuba Eucalyptus.The list of forest blocks and their distances from plant boundary are presented in Table TABLE-3.22 LIST OF FOREST BLOCKS WITHIN 10 KM RADIUS Name of forest Distance from the Direction from Sr. No. block site (km) the site 1 Palavakkam RF 5.6 SSW Terrestrial Biodiversity Flora of the Core area The core are is mostly Barren land and some part of the land consists green patces. The flora of the core area is mainly covered by the shrubs, under shrubs and herbs.species such as Prosopis juliflora, Acacia auriculoformis, calotrophis gigantic,opuntia stricta, Datura metel and Trees like Khejur (phoenix dactylifera), onla (Emblica officinalis), imli(tamarindus indicus), Aam(Mangifera indica). The list of flora is given in Table Vimta Labs Limited, Hyderabad/Coimbatore 105

116 District, Tamilnadu Chapter 3 Description of the environment TABLE-3.23 LIST OF FLORA IN THE CORE AREA Sr. No. Common name Scientific name 1 Arjun Terminalia arjuna 2 Bamboo Dendrocalamus strictus 3 Kekar Garuga pinnate 4 Kusum Schleichesia oleosa 5 Babul Acacia auriculoformis 6 Mango Mangifera indica 7 Amla Emblica officinalis 8 Hairy Senna Cassia hirsute 9 Unni chedi Lantana camara 10 Carrot grass Parthenium histerophorus Fauna of the Core Zone This area hosts common mongoose, field mouse, Bandicoot rat and birds like hose sparrow, common myna and koel white throated king fisher lapwing Black drongo There are no Schedule-I species in the core area. The list of fauna is given in Table TABLE-3.24 LIST OF FAUNA IN THE CORE ZONE Sr. No. Scientific name Common name Conservation status as per WPA (1972) 1 Milyus migrans Common Kite Sch-IV 2 Corvus splendens House crow Sch-II 3 Acridotheres tristicus Common myna Sch-IV 4 Passer domisticus House Sparrow Sch- V 5 Eudynamis scolopaceus Koel Sch-IV 6 Calotes versicolor Common garden Sch-IV lizard 7 Chameleon zeylanicus Chamaeleon Sch-IV 8 Bufo melanostictus Bufo Sch-IV 9 Bandicota indica Bandicoot Sch-IV Flora of the Buffer Zone Most commonly found species in the buffer zone and along the road side were Neem (Azadiractha indica), Ficus bengalensis, ficus religiosa, phenix spp,opuntia, Emblica officinalis, ziziphus Eucalyptus.The list of forest blocks and their distances from plant Acacia (Acacia nilotica) The list of flora is given in Table Vimta Labs Limited, Hyderabad/Coimbatore 106

117 District, Tamilnadu Chapter 3 Description of the environment TABLE-3.25 LIST OF FLORA FROM THE BUFFER ZONE Sr. No. Scientific name Family 1 Emblica officinalis Euphorbiaceae 2 Mangifera indica Anacardiaceae 3 Spondias mangifera Anacardiaceae 4 Saraca asoca Caesalpiniaceae 5 Ficus religiosa Moraceae 6 Annona squamosa Annonaceae 7 Ficus bengalensis Moraceae 8 Ziziphus jojoba Rhamnaceae 9 Ficus hispida Moraceae 10 Semecarpus anacardium Anacardiaceae 11 Anacardium occidentale Anacardiaceae 12 Helictres isora Tiliaceae 13 Anogeissus latifolia Combrataceae 14 Ficus carica Moraceae 15 Ficus glomerata Moraceae 16 Ocimum sanctum Labiatae 17 Ocimum sanctum Labiatae 18 Jatropha gossypifolia Euphorbiaceae 19 Jusrtia simplex Acanthaceae 20 Jussiaea suffraticosa Onagraceae 21 Abutilon indicum Malvaceae 22 Mimosa pudica Mimosaceae 23 Osimum americanum Labiataceae 24 Desmodium trifolium Fabaceae 25 Casurina Casuarinaceae 26 Melia azadiractha Meliaceae 27 Oxalis cornicula Oxalidaceae 28 Aegle marmelos Rutaceae 29 Tephrosia purpuria Fabaceae 30 Polyalthia longifolia Annonaceae 31 Feronia elephantum Verbanaceae Fauna of the Buffer Zone Primary field studies were conducted near villages, forest areas, waste lands, along the water bodies within 10 km radius of the project boundary and secondary data was collected through interaction with local forest officials. The details of the same are presented in Table Vimta Labs Limited, Hyderabad/Coimbatore 107

118 District, Tamilnadu Chapter 3 Description of the environment TABLE-3.26 LIST OF FAUNA IN THE BUFFER ZONE Sr. No. Scientific name Common name Conservation status as per WPA (1972) I.Aves 1 Milyus migrans Common Kite Sch-IV 2 Corvus corvus Jungle crow Sch-IV 3 Corvus splendens House crow Sch-V 4 Halcyon symyrnensis White Kingfisher Sch-IV 5 Ceryle rudis Pied kingfisher Sch-IV 6 Columba livia Rock Pigeon Sch-IV 7 Bubo bubo Indian great horned Owl Sch-IV 8 Copsychus saularis Magpie Robin Sch-IV 9 Oriolus oriolus Indian Oriole Sch-IV 10 Temenuchus Brahmny Myna Sch-IV pagodarum 11 Acridotheres tristicus Common myna Sch-IV 12 Ploceus philippinus Weaver bird Sch-IV 13 Uroloncha striata Spotted munia Sch-IV 14 Passer domisticus House Sparrow Sch-IV 15 Megalaima merulinus Indian Cuckoo Sch-IV 16 Eudynamis scolopaceus Koel Sch-V 17 Centropus sinensis Crow Pheasant Sch-IV 18 Psittacula crammeri Rose ringed parakeet Sch-IV 19 Coracias bengalensis Indian Roller Sch-IV 20 Merops leschenaultia Chestnut headed Bee Sch-IV Eater 21 Alcedo atthis Common Kingfisher Sch-IV 22 Microfus affinis House swift Sch-IV 23 Caprimulgus asiaticus Common Indian jar Sch-IV 24 Bubulcus ibis Cattle Egret Sch-IV 25 Ardeola grayii Pond Heron Sch-IV 26 Pavo cristatus Peacock Sch-I II.Reptiles 1 Calotes versicolor Common garden lizard Sch-IV 2 Chameleon zeylanicus Indian chameleon Sch-IV 3 Bangarus spp. Krait Sch-IV 4 Naja naja Indian cobra Sch-IV III.Butterflies 1 Pachliopta hector Lin. Crimson rose Sch-IV 2 Papilio demoleu Lime butterfly Sch-IV 3 Junoria almanac Peacock pansy Sch-IV 4 Hypolimnas bolina Great egg fly Sch-IV 5 Euploea core Common crow Sch-IV 6 Neptih hylas moore Common sailor Sch-IV Vimta Labs Limited, Hyderabad/Coimbatore 108

119 District, Tamilnadu Chapter 3 Description of the environment Sr. No. Scientific name Common name Conservation status as per WPA (1972) 7 Eurema hecabe Common grass yellow Sch-IV IV.Amphibians 1 Rana tigrina Bull frog Sch-IV 2 Bufo malanosticus Bufo Sch-IV V.Mammals 1 Bandicota indica Bandicoot Sch-IV 2 Rhinolopus spp. Bat Sch-IV 3 Hipposiderus spp. Bat Sch-IV 4 Presbytis entellus Langur Sch-II 5 Mucaca mulata Monkey Sch-II 6 Rattus sp. Rat Sch-V 7 Funambulus spp. Squirrel Sch-IV 8 Rattus norvegicus Field mouse Sch-V 9 Lepus nigricollis Hare Sch-IV 10 Rattus rattus House rat Sch-V Aquatic ecosystems Phytoplankton Phytoplankton forms the basis of food chain in any aquatic water body. The diversity and abundance of phytoplankton mainly depends on the region, type of water body, either lentic or lotic, the nutrient flux in the system and the sunlight available for photosynthesis. These factors together form the dynamics of phytoplankton productivity over the seasons. The phytoplankton of given water body determines the zooplankton populations and the fish productivity of the ecosystem. Phytoplankton group reported from the study area were Basillariophyceae, Chlorophyceae, Myxophyceae and Euglenophyceae members. About 20 species of phytoplankton were reported from all the locations. Dominance of Bacillariophyceae members followed by Myxophyceae was observed in studies samples. The highest percentage was Ankistrodesmus sp. and Navicula sp. and the lowest percentage was ophora sp and Synedra sp. was observed. Zooplankton The zooplankton of the aquatic water body are the primary consumers and also in cases secondary producers which play an important role for the fisheries of that system. The diversity and abundance of zooplankton also depends on whether the water body is eutrophic or oligotrophic. About 14 species of zooplankton were reported from all the locations. They also are good representatives of the ecosystem health. The amount and type of pollutants in the water body determine the type of zooplankton species. Species of copepod will usually dominate in the tropical region while more eutrophicated waters with high Vimta Labs Limited, Hyderabad/Coimbatore 109

120 District, Tamilnadu Chapter 3 Description of the environment nutrient or organic loads will harbor high number of crustaceans and arthropods. The less polluted waters will have more of cladocerans and rotifers. Among the zooplankton group, Asplancha sp.had highest percentage composition and the lowest percentage composition was of Ceriodaphnia sp. in the total zooplankton. The list of plankton recorded in fresh water bodies in study area during study period are presented in Table TABLE-3.27 LIST OF PLANKTON RECORDED DURING STUDY PERIOD Sr. No. Phytoplankton Zooplankton 1 Gyrosigma sp. Keratella monospina 2 Achananthes affinis Brachirous caudatus 3 Gyrosigma accuminatus Asplancha brighwell 4 Pandorina sp. Colpidium colpoda 5 Ankistrodesmus falcatus Daphnia sp. 6 Ankistrodesmus sp. Ceriodaphnia reticulate 7 Pediastrum boryanum Mesocyclops leuckarti 8 Scenedesmus bijuga Mesocyclops hyalinus 9 Melosira granulate Coleps hirsutus 10 Cyclotella meneghiana Arcella sp. 11 Microcystis sp. Actinophyros sp. 12 Navicula gracilis Asplancha sp. 13 Nitzschia gracilis Ceriodaphnia sp. 14 Chroococcus minutes Mesocyclops sp. 15 Spirulina princepes 16 Pinnularia braunii 17 Synedra tabulate 18 Ophora sp. 19 Cymbella sp. 20 Navicula radiosa Fishes The Arani River is a perennial river and the list of principle catchers is given in Table TABLE-3.28 AQUATIC FAUNA FROM STUDY AREA Sr. No. Local Name Zoological Name 1 Catla Catla catla 2 Rohu Labeo rohita 3 Mrigal Cirrhinus mrigala 4 Silver Carp Thirmethrix molitrix 5 Grass Carp Ctenopheringodon idella 6 Common Carp Cyprinus carpio Vimta Labs Limited, Hyderabad/Coimbatore 110

121 Conclusion Rapid Environmental Impact Assessment for the proposed augmentation & District, Tamilnadu Chapter 3 Description of the environment From the field observations it can be concluded that the forests in the study area are under anthropogenic pressure and show signs of degradation in the form of tree cutting, lopping, grazing and collection of NTFPs and habitat fragmentation. As per MOEF and Forest Department of Tamilnadu state reveals that there are no Wildlife sanctuaries, National parks/biosphere reserves in 10 km radius from the proposed site boundary. As per the records of the Botanical Survey of India there are no plants of conservation importance in the study area. It can be concluded that there is one species belonging to Sch-I,2 species belongs to Sch-II and rest of species belongs Sch-III, Sch-IV and Sch-V of Wildlife Protection Act, Demography and Socio-Economics The growth of industrial sectors and infrastructure developments in and around the agriculture dominant areas, villages and towns are bound to create its impact on the socio-economic aspects of the local population. The impacts may be positive or negative depending upon the developmental activity. To assess the impacts on the socio-economics of the local people, it is necessary to study the existing socio-economic status of the local population, which will be helpful for making efforts to further improve the quality of life in the area of study. To study the socio-economic aspects of people in the study area around the plant site, the required data has been collected from various secondary sources and supplemented by the primary data generated through the process of a limited door to door socio-economic survey Methodology adopted for the Study The methodology adopted for the study is based on the review of secondary data, such as District Census Statistical Handbooks-2001 of Thiruvallur district and the records of National Informatics Center, New Delhi, for the parameters of demography, occupational structure of people within the general study area of 10-km radius around the plant site Review of Demographic and Socio-Economic Profile The sociological aspects of this study include human settlements, demography, social such as scheduled castes and scheduled tribes and literacy levels besides infrastructure facilities available in the study area. The economic aspects include occupational structure of workers. The salient features of the demographic and socio-economic details are described in the following sections. Vimta Labs Limited, Hyderabad/Coimbatore 111

122 Demography Rapid Environmental Impact Assessment for the proposed augmentation & District, Tamilnadu Chapter 3 Description of the environment Distribution of Population As per 2001 census, the study area consists of 2,78,458 persons. The distribution of population in the study area is given in Table The males and females constitute % and % of the study area population respectively. TABLE-3.29 DISTRIBUTION OF POPULATION Particulars 0-3 km km km 0-10 km No. of House holds Male Population Female Population Total Population Avg. House hold size Male % Female % Source: Thiruvallur District Census Statistics-2001 Average Household Size The average household size of the study area is The low family size could be attributed to a high degree of urbanization with migration of people with higher literacy levels who generally opt for smaller family size and family welfare measures. Sex Ratio The configuration of male and female indicates that the males constitute to about 50.86% and females to 49.14% of the total population as per 2001 census records. The sex ratio i.e. the number of females per 1000 males indirectly reveals certain sociological aspects in relation with female births, infant mortality among female children and single person family structure, a resultant of migration of industrial workers. The study area on an average has 966 females per 1000 males as per 2001 census Social Structure As per 2001 census, the percentage of scheduled caste population is 21.45% within 10-km radius study area. The percentage of Schedule Tribe population is 1.4%. The distribution of population by social structure is given in Table Vimta Labs Limited, Hyderabad/Coimbatore 112

123 District, Tamilnadu Chapter 3 Description of the environment TABLE DISTRIBUTION OF POPULATION BY SOCIAL STRUCTURE Particulars 0-3 km 3-7 km 7-10 km 0-10 km Schedule Caste % of total population Schedule Tribes % of total population Total SC and ST population % To total population other caste population % To total population Total population Literacy Levels The study area experiences a literacy rate of 63.73%. The distribution of literate and literacy rate in the study area is given in Table The male literacy rate i.e. the percentage of male literates to the total males of the study area works out to be 57.34%. The female literacy rate, which is an important indication for social change is observed to be 42.66%. TABLE 3.31 DISTRIBUTION OF LITERATE AND LITERACY RATES Particulars 0-3 km 3-7 km 7-10 km 0-10 km Total literate Male population Female population Average literacy (%) Male Literate % To Study area literate % To total male population Female Literate % To Study area literate % To total female population Total Population Occupational Structure The occupational structure of residents in the study area is studied with reference to main workers, marginal workers and non-workers. The main workers include 10 categories of workers defined by the Census Department consisting of cultivators, agricultural labourers, those engaged in live-stock, forestry, fishing, mining and quarrying; manufacturing, processing and repairs in household industry; and other than household industry, construction, trade and commerce, transport and communication and other services. Vimta Labs Limited, Hyderabad/Coimbatore 113

124 District, Tamilnadu Chapter 3 Description of the environment The marginal workers are those workers engaged in some work for a period of less than six months during the reference year prior to the census survey. The non-workers include those engaged in unpaid household duties, students, retired persons, dependents, beggars, vagrants etc.; institutional inmates or all other non-workers who do not fall under the above categories. As per 2001 census records, altogether the main worker works out to be 30.71% of the total population. The marginal workers and non-workers constitute to 8.19% and 61.11% of the total population respectively. The distribution of workers by occupation indicates that the non-workers are the predominant population. The occupational structure of the study area is shown in Table The demographic details in the study area are provided as Annexure 10. TABLE-3.32 OCCUPATIONAL STRUCTURE Particulars 0-3 km 3-7 km 7-10 km 0-10 km Total main workers % to total population Marginal workers % to total population Non-workers % to total population Total Population Vimta Labs Limited, Hyderabad/Coimbatore 114

125 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures 4.0 ANTICIPATED ENVIRONMENTAL IMPACTS AND MITIGATION MEASURES 4.1 Introduction This chapter presents identification and appraisal of various impacts due to the proposed expansion of the existing coal based thermal power plant during erection and operational phases. The environmental impacts are categorized as primary or secondary. Primary impacts are those, which are attributed directly to the project and secondary impacts are those, which are indirectly induced and typically include the associated investment and changed pattern of social and economic activities by the proposed activity. The mitigation measures proposed for minimizing the impacts have also been discussed in this chapter. Environment Management Plan (EMP) is developed to minimize adverse impacts and to ensure that the environment in and around the project site is well protected. The EMP has been prepared for both construction and operation phases of the proposed facilities. The impacts have been assessed for the power plant assuming that the pollution due to the existing activities has already been covered under baseline environmental monitoring and continue to remain same till the operation of the project. The erection and operational phase of the proposed expansion project comprises various activities each of which may have an impact on some or other environmental parameters. Various impacts during the erection and operation phase on the environment have been studied to estimate the impacts on the environmental attributes and are discussed in the subsequent sections. 4.2 Impacts during Construction Phase This includes the following activities related to land acquisition, leveling of site, construction of related structures and installation of related equipment Impact on Land Use The existing plant operates in area of ha (62.99 acres). The land identified for the proposed addition of 1 x 350 MW thermal power plant unit is about ha (28.39 acres) adjacent to the existing plant site. About 3.25 ha (8.03 acres) of the land will be used as ash dyke. Main plant facilities and ancillary facilities will occupy about ha (30.76) acres of land. Entire site (existing & proposed) is under the ownership of the project proponent and there is no forest or ecological sensitive land within the existing & additional site. No residential or habitation areas are proposed to be acquired, hence no displacement of residential areas. Construction of additional facilities will lead to permanent change in land use pattern at the proposed adjacent site as a direct impact. VIMTA Labs Limited, Hyderabad 115

126 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures The proposed expansion involves erection of large scale civil works including levelling within project premises. The earthen material generated during construction of additional water storage reservoir within the site premises will be used for elevating plant area. The environmental pollution impacts during erection phase would be temporary and are expected to gradually stabilize by the time of commissioning of proposed expansion activity. There are no sensitive locations such as archaeological monuments, sanctuaries, national parks, critical pollution zones etc., within 10 km radial distance around the existing plant site. No major changes in land use pattern of study area (region) will occur due to the project activities. Hence, no major impact is envisaged on land use pattern of the project site (core zone) or the buffer zone Impact on Soil The construction activities will result in loss of vegetation cover, topsoil and earthen material to some extent in the plant area. However, it is proposed to use the soil and earthen material for greenbelt development and levelling of project site. Additional greenbelt will be developed in phased manner from erection stage onwards. Apart from localized construction impacts at the plant site, no adverse impacts on soil in the surrounding area are anticipated Impact on Topography The existing plant site is partially plain and undulating with a general elevation of about 18 m above MSL. It is proposed to level the additional project site and to use the earthen material excavated from the proposed additional reservoir inside the premises itself. There will not be any tall structures except the stacks for plume dispersion. Also, the contours of natural drainage will not be disturbed. In view of the above, there will not be any major impacts on topography of the project site Impact on Air Quality The main sources of emission during the erection period are the movement of equipment at site and dust emitted during the leveling, grading, earthwork, foundation works and exhaust emissions from vehicles and equipment deployed during the construction phase is also likely to result in marginal increase in the levels of SO 2, NO x, PM and CO. The impact will be for short duration and confined within the project boundary and is expected to be negligible outside the plant boundaries. VIMTA Labs Limited, Hyderabad 116

127 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures The impact will, however, be reversible, marginal and temporary in nature. Proper maintenance of vehicles and construction equipment will help in controlling the gaseous emissions. Water sprinkling on roads and construction site will prevent fugitive dust Impact on Water Quality Impact on water quality during erection phase may be due to non-point discharge of solids from soil loss and sewage generated from the construction workforce stationed at the site. Further, the construction will be more related to mechanical fabrication, assembly and erection; hence the water requirements would be small. Sanitary sewage generated by the temporary workforce will be handled by the existing STP itself. The overall impact on water environment during erection phase due is likely to be short term and insignificant Impact on Noise Levels Vehicular traffic, loading and unloading of construction material, fabrication and handling of equipment and materials are likely to cause an increase in the ambient noise levels. The areas affected are those close to the site. However, the noise will be temporary and will be restricted mostly within plant area. The noise control measures during erection phase include provision of caps on the equipment and regular maintenance of the equipment Impact on Terrestrial Ecology The land required for the expansion of power plant is a Barren land and cutting of trees are not required. Therefore, no major loss of biomass is envisaged during construction phase. Although the land required for the expansion of the plant would be put to industrial use, there may not be any significant impact on soil and agriculture in general. These impacts are, however, restricted to the early phase of construction. The removal of herbaceous vegetation from the soil and loosening of the topsoil generally causes soil erosion during dry season. However, such impacts would be primarily confined to the project site during initial periods of the construction phase and would be minimized through adoption of mitigatory measures like paving and surface treatment, water sprinkling and appropriate plantation program. The project site and township area will be extensively landscaped with the development of green belt consisting of a variety of taxa, which would enrich the ecology of the area and add to the aesthetics. VIMTA Labs Limited, Hyderabad 117

128 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures 4.3 Impacts during Operational Phase The expansion activity will involve a proposed power generation of 485 MW (1 x 135 MW + 1 x 350 MW) of power generation in addition to the existing 60 MW. The following activities related to the operational phase will have varying impacts on the environment and are considered for impact assessment: Topography Topography and climate; Air Environment; Water resources and quality; Land use; Soil quality; Solid waste; Noise levels; Terrestrial and aquatic ecology; Demography and socio-economics; and Infrastructural facilities. Most of the area of the plant site is partially plain with slight undulations and it will be maintained plain during post-project scenario. There will not be any topographical changes during operation of the project Impact on Air Quality Point Sources Being a coal based thermal power project, the important air pollutants are Sulphur dioxide (SO 2 ), Oxides of Nitrogen (NO x ) and Particulate Matter (PM). Prediction of impacts on air environment has been carried out by employing mathematical model based on a steady state Gaussian plume dispersion model designed for multiple point sources for short term. In the present case, AERMOD - designed for multiple point sources for short term and developed by United States Environmental Protection Agency [USEPA] has been used for simulations from point sources. The model simulations deal with dispersion of three major pollutants viz., Sulphur Dioxide (SO 2 ), Oxides of Nitrogen (NO x ) and Particulate Matter (PM) emitted from the stacks Air Pollution Impact Prediction through Modelling a. AERMOD View AERMOD is an air dispersion-modeling package, which seamlessly incorporates the popular USEPA Models, ISCST3, ISC-PRIME and AERMOD into one interface without any modifications to the models. These models are used extensively to assess pollution concentration and deposition from a wide variety of sources. VIMTA Labs Limited, Hyderabad 118

129 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures b. AERMOD Model The AMS/EPA REGULATORY MODEL (AERMOD) was specially designed to support the Environmental Regulatory Modeling Programs. AERMOD is a regulatory steady state-modeling system with three separate components; AERMOD (AERMIC Dispersion Model); AERMAP (AERMOD Terrain Preprocessor); and AERMET (AERMOD) Meteorological Preprocessor. The AERMOD model includes a wide range of options for modeling air quality impacts of pollution sources, making it popular choice among the modeling community for a variety of applications. AERMOD requires two types of meteorological data files, a file containing surface scalar parameters and a file containing vertical profiles. These two files are provided by AERMET meteorological pre-processor program. PRIME building downwash algorithms based on the ISC PRIME model have been added to the AERMOD model; Use of arrays for data storage; Incorporation of EVENT processing for analyzing short-term source culpability; Explicit treatment of multiple year meteorological data files and the annual average; and Options to specify emissions that vary by season, hour-of-day and day-ofweek. Deposition algorithms have been implemented in the AERMOD model results can be output for concentration, total deposition flux, dry deposition flux, and / or wet deposition flux. The model contains algorithms for modeling the effects of settling and removal of large particulates and for modeling the effects of precipitation scavenging for gases or particulates. c. AERMET In order to conduct a refined air dispersion modeling project using the AERMOD short-term air quality dispersion model, it is necessary to process the meteorological data representative of the study area being modeled. The collected meteorological data is not always in the format supported by the model, therefore the meteorological data needs to be pre-processed using AERMET program. The AERMET program is a meteorological preprocessor, which prepares hourly surface data and upper air data for use in the AERMOD air quality dispersion model. AERMET is designed to allow future enhancements to process other types of data and to compute boundary layer parameters with different algorithms. AERMET processes meteorological data in three stages and from this process two files are generated for use with the AERMOD model. VIMTA Labs Limited, Hyderabad 119

130 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures A surface file of hourly boundary layer parameters estimates a profile file of multiple-level observations of wind speed, wind direction, temperature and standard deviation of the fluctuating wind components. d. Application of AERMOD AERMOD model with the following options has been employed to predict the cumulative ground level concentrations due to emissions from the proposed activity. All terrain dispersion parameters are considered; Predictions have been carried out to estimate concentration values over radial distance of 10 km around the project area; Uniform polar receptor network has been considered; Emission rates from the sources were considered as constant during the entire period; The ground level concentrations computed without any consideration of decay coefficient; Calm winds recorded during the study period were also taken into consideration; 24 hourly mean ground level concentrations were estimated using the entire meteorological data collected during the study period; and The study area is used to represent the graphical output of the GLC s using the terrain processor. e. Meteorological Data The hourly meteorological data recorded at site is converted to the mean hourly meteorological data as specified by CPCB and the same has been used in the model. Hourly mixing heights are taken from the Atlas of Hourly Mixing Height and Assimilative Capacity of Atmosphere in India published by India meteorological department, 2008, New Delhi. The meteorological data recorded during study period continuously on wind speed, wind direction, temperature etc., have been processed to extract the data required for simulation by AERMOD using AERMET. The meteorological data used are given in Table 4.1. VIMTA Labs Limited, Hyderabad 120

131 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Time in hours TABLE-4.1 HOURLY MEAN METEOROLOGICAL DATA Wind speed in m/s Wind direction in degrees Air Temperature in K Stability class Mixing height in m 12:10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 AM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM :10:00 PM f. Emission Factors Considered in Model The modelling has been carried to predict the impacts of the power generation operations with a total generation capacity of 545 MW, considering emission factors for the worst case i.e. without control measures. The emission factor has been estimated for 2 nos. of point sources as given in Table-4.2. The graphical representation of ground level concentrations (GLCs) is shown in Figure-4.1 VIMTA Labs Limited, Hyderabad 121

132 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures TABLE-4.2 STACK DETAILS Particulars Existing Proposed Stack 1 Stack 2 Material of Construction RCC RCC Stack attached to 1 x 60 MW & 1 x 350 MW 1 x 135 MW Stack height (m) Stack diameter (mm) approx Volume Flow Rate (m 3 /s) Velocity of flue gas (m/s) Temperature of flue gas ( C) Flue gas specific volume (kg/nm³) Fuel Consumption (Kg/s) Sulphur content (% w/w) Emission rate NO x (g/s) Emission rate SO 2 (g/s) Emission rate PM (g/s) g. Presentation of Results The model simulations have been carried out for pre monsoon season. For the short-term simulations, the ground level concentrations (GLCs) were estimated around 220 receptors to obtain an optimum description of variations in concentrations over the site in 5 km radius covering 16 directions. The maximum incremental ground level concentrations and resultant concentrations for PM, SO 2 and NOx are given in Table-4.3 and Table-4.4 respectively. Similarly, the isopleths for various pollutant concentrations are enclosed. The CPCB permissible ambient air quality standards are given in Table-4.4. TABLE-4.3 PREDICTED 24-HOURLY SHORT TERM INCREMENTAL CONCENTRATIONS Season Maximum Incremental GLCs ( g/m 3 Distance ) Direction (km) Pre-monsoon 2014 PM SO 2 NOx Imported coal East TABLE-4.4 RESULTANT CONCENTRATIONS DUE TO INCREMENTAL GLC's (WORST CASE SCENARIO) Pollutant Concentration ( g/m 3 ) Baseline Incremental Resultant Standards PM SO NOx VIMTA Labs Limited, Hyderabad 122

133 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures h. Discussions on Results of Assessment A perusal of previous sub-section reveal that the maximum incremental short-term 24 hourly ground level concentrations for PM, SO 2 and NOx likely to be encountered in the operation of the power project are 1.39, and g/m 3 respectively occurring at a distance of about 2.0 km in the East direction. The worst case maximum resultant 24 Hourly concentrations for PM, SO 2 and NO x after implementation of the proposed activity are 84.49, and µg/m 3 respectively. According to the above presented results, it can be stated that the impact of PM from proposed expansion would be negligible in core or buffer zone of the project. Even though, the incremental and resultant concentrations of SO 2 and NO x are significant to certain extent, they are well within the NAAQ limits and hence, the AAQ levels after implementation of the proposed activity will remain within the permissible limits. Hence, it can be stated that the AAQ of the area will be within the permissible limits of respective zones. VIMTA Labs Limited, Hyderabad 123

134 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures FIGURE-4.1 SHORT TERM 24 HOURLY INCREMENTAL GLCs OF PM VIMTA Labs Limited, Hyderabad 124

135 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures FIGURE-4.2 SHORT TERM 24 HOURLY INCREMENTAL GLCs of SO 2 VIMTA Labs Limited, Hyderabad 125

136 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures FIGURE-4.3 SHORT TERM 24 HOURLY INCREMENTAL GLCs of NOx VIMTA Labs Limited, Hyderabad 126

137 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Impact on Air Quality - Fugitive Emissions The fugitive dust emissions expected are from coal storage yards, coal conveyor belt area, ash dumping areas, transportation of fuel and solid waste. Coal handling unit will be properly operated with EMP suggested in this report, no major fugitive dust emissions are envisaged. Similarly, HCSD system of ash stacking will be practiced and hence, no dust emissions are envisaged from ash dump areas. The fuel will be conveyed through belts and the solid waste will be sent to dyke areas through pipeline. Hence, no dust emissions from handling are envisaged. However, internal roads are to be asphalted to further reduce fugitive dust emissions. The dust emissions, if any, from the above areas will be fugitive in nature and maximum during summer season (when the wind velocities are likely to be high) and almost nil during the monsoon season. The dust emissions are likely to be confined to the place of generation only. The quantification of these fugitive emissions from the area sources is difficult as it depends on lot of factors such as dust particle size, specific gravity of dust particles, wind velocity, moisture content of the material and ambient temperatures etc. Also, there is a high level of variability in these factors. Hence, these are not amenable for mathematical dispersion modelling. However, by proper usage of dust suppression measures, dust generation and dispersions will be reduced. The impact of fugitive dust emissions from the proposed units on air quality of the region is insignificant Impact on Water Resources and Water Quality The entire water demand for the existing and the proposed facilities will be met from the existing borewell within plant site. However, the impact on ground water level will be mitigated by adopting suitable rain water harvesting and ground water recharge measures. Ground water uptake will be limited by using rain water collected in a huge rain water harvesting pond with a collection capacity of 70 MLD. Additionally, a new rain water collection pond is also proposed for the expansion activity Impact on Water Quality The water balance and wastewater generation details have been described in Chapter-2. Total wastewater (including domestic wastewater) generation in the project will be about m 3 /day. Out of m 3 /day of wastewater generated, about m 3 /day will be re-used for boiler make-up. About m 3 /day will be used for ash quenching & coal dust suppression and the remaining 12.8 m 3 /day will be used for greenbelt development. Garland drains around the ash dyke site will be provided for the collection of runoff water during monsoon season. VIMTA Labs Limited, Hyderabad 127

138 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures The storm water in the project area will be collected through storm water drains and collected in the rain water collection pond, which is lined to prevent any contamination of ground water. The stored storm water will be utilized in the plant operation resulting in conservation of fresh water. Various types of wastewater to be generated from the plant with their quantity, expected pollutants and their respective treatment are provided in Table-4.5. TABLE-4.5 TYPE OF WASTEWATER GENERATION AND TREATMENT DETAILS Sources of wastewater Runoff Water From Coal Yard Runoff Water From Limestone Yard Neutralized Waste Water Treatment & Disposal The runoff from the coal yard will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt The runoff from the limestone yard will be collected in a settling tank. The clear water will be taken to a collection tank and used for watering of green belt Make-up water treatment plant waste will be taken to separate neutralization pit, neutralized and then pumped to the Common Monitoring Basin (CMB) Oily Waste Water Oil bearing effluent generated from fuel oil handling area plant floor wash etc. will be treated in an oil/water separator to separate oil from water and the treated waste water sent to CMB. The oily sludge will be collected and disposed offsite Sewage Water from Toilets in the Power Plant Boiler Blow Down Special Waste Water Clarifier Sludge Common Monitoring Basin The Sewage water generated from the Power Plant will be treated in an anaerobic filter and the treated effluent will be collected and used for horticulture. Suitable arrangements for collection of sludge, its compaction and safe disposal will be provided Boiler blow down waste water will be fed to neutralization pit of water treatment plant and from there it will be sent CMB Special waste water like Air Preheater washing water, acid cleaning of boiler etc. will be collected and treated in a chemical waste cleaning plant to make it suitable for offsite disposal The sludge collected in the clarifier will be taken to a sedimentation tank and the clear water will be sent to CMB. The collected sludge will be taken to a sludge drying bed and spread over the green belt within the plant boundaries The outlet from the CMB after ensuring that the quality meets the requirements stipulated in the PCB norms, will be used for coal yard dust suppression, limestone dust suppression and watering of green belt VIMTA Labs Limited, Hyderabad 128

139 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures The expected quality of raw and treated wastewater from the power plant including sewage water and discharge limits as specified by environment protection rules is given in Table-4.6. TABLE-4.6 EXPECTED QUALITY OF WASTEWATER Sr. No. Parameter Unit Raw wastewater Treated Wastewater Permissible Limits as per GSR 422 (E) for On-land Discharge (Irrigation) 1 ph to to to Suspended Solids mg/l 100 to 500 < Oil & Grease mg/l 10 to 200 < Total Dissolved Solids mg/l 500 to < BOD mg/l 250 to 350 < COD mg/l 450 to 600 <100-7 Zinc mg/l 1 to 5 <1 - Entire treated wastewater will be reused / recycled and zero discharge from the plant will be ensured. Thus, no impact on the natural water bodies is envisaged Impact on Land Use The land additionally procured for the proposed 1 x 350 MW unit is about ha (28.39 acres). About 3.25 ha of the land will be used for ash disposal. Greenbelt including existing green cover will be developed in an area of about ha (32.86 acres) covering 35.96% of the total plant area upon expansion. The additional greenbelt proposed will have a positive impact on land. There will be minimum changes in land use during the operational phase of the project. Hence, no major impacts are envisaged during operational phase of the project Impact on Soil Most of the impacts of power plant project on soil quality are restricted to the erection phase, which will get stabilized during operational phase. The impact on the topsoil will be confined to the main plant area. Further, the additional greenbelt proposed will have a very positive impact on soil quality. The probable sources of degradation of soil quality will be due to generation & disposal of ash and fugitive dust emissions. However, the impacts due to disposal of ash are covered under Section The airborne fugitive dust from the plant is likely to be deposited on the topsoil in the immediate vicinity of the plant boundary. However, the fugitive emissions are likely to be controlled to a great extent through proposed control measures like water sprinkling and development of greenbelt development. Hence, no impact is envisaged on soil quality of the project site. VIMTA Labs Limited, Hyderabad 129

140 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Impact of Solid Wastes Ash is the major solid waste to be generated from a coal based thermal power plant. Coal consumption of 2.31 MTPA having 9.0% ash content was considered for estimation of ash generation. Ash will be generated as both forms viz. bottom ash and fly ash. About 80% of the total ash generations will be fly ash and remaining 20% comes as bottom ash. The fly ash is the important air pollutant, which emits to outside environment through stacks attached to boilers. ESPs with efficiencies over 99.99% shall be provided to prevent ash dispersions into ambient air. The details of the solid waste generation are given in Table-4.7. TABLE-4.7 EXPECTED SOLID WASTE FROM POWER PLANT Sr. No. Plant Quantity of Generation Mode of Disposal 1 Ash* MTPA Emphasis will be given for supply to Fly ash MTPA potential users in dry from. Bottom ash MTPA Remaining ash will be disposed into HDPE lined ash dyke through HCSD method 2 Used Oil 2000 KLPA Will be supplied to authorized recyclers 3 Sewage sludge 2.4 TPA Sent to sludge drying beds and used as manure 4 Domestic solid waste / municipal solid waste 5.25 TPA Organic portion will be dried, composted and used as manure. Inorganic portion will be handed to authorised recyclers * Ash calculations are based the 9% ash content of Indonesian coal considering worst case Fly ash will be collected from ESP hoppers in dry from and supplied to potential ash users depending on the demand. The balance unutilized ash will be disposed of using High Concentrated Slurry Disposal (HCSD) technology. An area of about 2.61 ha has been identified for ash dyke in addition to the existing ash dyke of 0.64 ha within the project premises. In view of the proposed HCSD ash disposal technology, the impact of ash dyke supernatant runoff would not be expected and the impacts on surrounding environment would be insignificant. However, it is also proposed to provide the ash dyke with an impervious HDPE layers. The sludge from sewage treatment plant will be dried, vermi-composted and used as manure for greenbelt maintenance. Canteen/sanitary waste will be composted and used as manure for greenbelt development. With the implementation of above precautionary measures, the impacts due to solid waste disposal will be minimum. Impact of Ash Dyke on Surface Water In ash disposal, High Concentration slurry disposal method will be adopted. The bottom ash slurry and fly ash slurry from the both the units will be led to common slurry sump of the combined ash slurry disposal pump house. In view of the proposed HCSD ash disposal technology, the impact of ash dyke supernatant run off would not be expected. Hence, the impact of the ash dyke on the surface water will be insignificant. VIMTA Labs Limited, Hyderabad 130

141 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Impact of Ash Dyke on Ground Water The possibility of groundwater contamination due to the leaching of metals from the ash dyke will be examined based on soil investigation study. Fortification around the dyke will be provided with proper compaction at maximum dry density. The co-efficient of permeability will be much less than the natural deposits to further reduce the drainability. However, with the passage of time, more and more fly ash particles will get deposited in the pore spaces of the top soil making it essentially non-porous and impervious and in view of the above, contamination through leaching is not envisaged. However, it is also proposed to provide the ash dyke with an impervious bottom HDPE layers. In view of the above mitigative measures, no surface water or groundwater pollution is anticipated from the ash disposal area. Similarly, as the other solid wastes also used properly, no impact of solid waste is envisaged Impacts on Ecology Detailed flora and fauna studies were carried out during study period and the details are presented in Section-3.10 of Chapter-3. As per records of forest department of Thiruvallur district, literature survey and also from field studies, there are no endangered, threatened and protected plants as per Wildlife Protection Act, It is proposed to develop additional greenbelt with an average width of about 50 m to 100 m around plant site and implementation of eco development along with local people will enhance the greenery of the area. Hence, no significant adverse impact is envisaged on terrestrial ecology. The impacts on aquatic ecology due to proposed expansion activity would be negligible as the treated effluents from the plant will meet the prescribed standards prior to final discharge. Similarly, as the discharge water will not have much higher temperature than the receiving body, no thermal effects on receiving body due to discharge are envisaged. Hence, the impacts on ecology of the region will be insignificant Impact on Noise Levels The main noise generating stationary sources from the power plant will be pumps, compressors and boilers. The noise levels at the source for these units will be in the range of db(a). The noise dispersion from the plant units has been computed based on the mathematical model. The major noise generating sources from the plant are identified and listed in Table-4.8. These are considered as input to the noise model. VIMTA Labs Limited, Hyderabad 131

142 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures TABLE-4.8 MAJOR NOISE GENERATING SOURCES Sr. No. Sources Noise Level in db(a) [1.0 m away] Nature of Noise 1 Turbine units 85 Continuous 2 Air compressors 85 Continuous 3 Transformer 75 Continuous 4 Boilers 85 Continuous Presentation of Results The incremental noise levels are computed at plant site at 100 m X 100 m grid intervals over an area of 10 km X 10 km study area. The predicted results of incremental noise levels at each grid points are used to draw noise contours. The predicted noise contours around expected sources are shown in Figure-4.4. The predicted noise levels at the boundary due to various plant activities will be ranging in between 32 to 36 db(a). The incremental noise levels will be less than 40 db(a) at all the surrounding habitations. It is seen from the simulation results that the incremental noise levels will be well within the CPCB standards Impact on Work Zone Boilers are the high noise generating equipment in the existing & the proposed units. However, impacts on the working personnel are not expected to be significant on account of the high level of automation of the plant, which means that workers will be exposed for short duration only. The noise generation during operational phase would be at source itself through different measures such as inspection, operation and maintenance at regular intervals. The noise control measures as described in EMP will be fully followed. The occupational noise exposure to the workers in the form of 8 hourly time weighted average will be maintained well within the prescribed OSHA standards [<90 db (A)]. Hence, the impact on occupational health of workers would be insignificant. VIMTA Labs Limited, Hyderabad 132

143 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures FIGURE-4.4 PREDICTED NOISE DISPERSION CONTOURS VIMTA Labs Limited, Hyderabad 133

144 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Impact on Community As per the location of power plant, the minimum distance maintained between existing & proposed major noise sources and the outer periphery of the project site will be more than 500 m. The cumulative incremental impact of all noise sources at boundary will range in between 32 to 36 db (A) Prediction of Impacts on Socio-Economics No shifting of human habitations are envisaged for siting of the proposed units, as the land is a barren land which has been acquired by the proponent. Hence, no resettlement activities are envisaged. Unskilled manpower will be met from nearby villages during erection phase. The project will also help in generation of the indirect employment apart from direct employment. This will be a positive socio-economic development for the region. There will be a general upliftment of standard of living in the region Impacts on Public Health and Safety The discharge of waste materials (stack emission, wastewater and solid wastes) from process operations may have potential impact on public safety and health. The wastewater generated from power plant will be treated before discharging outside. It is proposed to reuse the wastewater to the maximum extent. Since, the adverse impacts on ambient air and soil quality are predicted to be low it is anticipated that with effective implementation of control measures suggested for pollution control, the impact on public health will be minimum. 4.4 Environment Management Plan during Erection Phase During erection phase, the construction activities like site levelling, grading, transportation of the construction material cause various impacts on the surroundings. However, the erectional phase impacts are temporary and localised phenomena except the permanent change in local landscape and land use pattern of the project site Land Environment Management Preparation of site will involve excavations and fillings. The earthen material generated during excavations and site grading periods, shall be properly dumped and slope stabilisation shall be taken. The topsoil generated during erections shall be preserved and reused for plantations. No nallas or water courses are present in the project site. The nearest river (R. Arani) is at about 7.4 km, SSE from the plant site. However, natural drainage pattern shall not be disturbed as far as possible. The additional greenbelt area shall be delineated before start-up of earthwork and tree plantation shall be taken up during erection stage itself. VIMTA Labs Limited, Hyderabad 134

145 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Air Quality Management The activities like site development, grading and vehicular traffic contribute to increase in PM and NO x concentrations. The mitigation measures recommended to minimize the impacts are: Water sprinkling in construction area; Asphalting the main approach road; Proper maintenance of vehicles and construction equipment; and Tree plantation in the area earmarked for greenbelt development Water Quality Management The soil erosion at site during heavy precipitation contributes to the increase in suspended solids. The wastewater from vehicle and construction equipment maintenance centre will contribute to oil and grease concentration. The wastewater from labour colony will contribute to higher BOD concentrations. The mitigation measures recommended to minimize the impacts are: Sedimentation tank to retain the solids from run-off water; Oil and grease trap at equipment maintenance centre; Packaged STP / septic tanks to treat sanitary waste at labour colony; and Utilizing the wastewater in greenbelt development Noise Level Management Operation of construction equipment and vehicular traffic contribute to the increased noise level. Recommended mitigation measures are: Enclosures for noise making units like pumps, compressors, etc.; Good maintenance of vehicles and construction equipment; Plantation of trees around the plant boundary to attenuate the noise; and Provision of earplugs and earmuffs to workers Ecological Management Clearing of vegetation will not be required as the additional land acquired is a barren land. Thus, there will not be any ecological impact due to the project in its erection stage. Furthermore, additional greenbelt with a vegetation density of over 2500 trees/ha has been planned which has a positive impact on the site ecology. 4.5 Environment Management Plan during Operation Phase During operation phase, the impacts on the various environmental attributes should be mitigated using appropriate pollution control equipment. The Environment Management Plan prepared for the proposed expansion project aims at minimizing the pollution at the source itself. VIMTA Labs Limited, Hyderabad 135

146 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Air Pollution Management Fugitive and stack emissions from the power plant will contribute to increase in concentrations of PM, SO 2, NO x and HCs. The mitigative measures recommended for the plant are: Installation of ESP of efficiency more than 99.90% to limit the PM concentrations below 50 mg/nm 3 ; Provision of stack of 220 m height for wider dispersion of gaseous emissions; Provision of water sprinkling system at raw material storage yard; Asphalting of the roads within the plant area; Provision of dust extraction systems at dust generating source. Developing of greenbelt around the plant to arrest the fugitive emissions; Online flue gas monitors as well as flue gas flow rates and temperature measurement shall be provided for all stacks; and Usage of washed / beneficiated coal may be explored. The fugitive dust emissions shall be controlled by installation of closed conveyor system along with suitable dust suppression measures Water Pollution Management Wastewater will be generated from boilers & DM plant from the project. Besides, domestic wastewater from canteen and employees wash area will also be generated. The recommended measures to minimise the impacts and conservation of fresh water are: Recycling of wastewater for ash disposal, coal handling and service water requirements; The effluent carrying oil spillage in the plant area shall be sent to oil-water separator for removal of oil; Coal stock piles and ash dyke shall be provided with garland drains and water shall be treated for suspended / floating solids; Adequate treatment of wastewater prior to recycling/reuse to maximum extent; Provision of sewage treatment plant to treat domestic sewage generated from plant; Utilization of treated domestic wastewater in toilet flushing & greenbelt development; Lining of effluent dyke suitably to prevent any seepage into ground to avoid any groundwater contamination; Provision of storm water system to collect and store run-off water during rainy season and utilization of the same in the process to reduce the fresh water requirement; Suitable rainwater harvesting structures to be constructed. VIMTA Labs Limited, Hyderabad 136

147 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Rainwater Harvesting System Rainwater harvesting structures will be provided to recharge the groundwater resources in the region. The run-off water from the roof of the structures and paved areas shall be collected through storm water drainage system and led to rain water harvesting structure Noise Pollution Management In the process, various equipments like pumps, compressors etc., generate noise. The recommendations to mitigate higher noise levels are: Equipments should be designed to conform to noise levels prescribed by regulatory authorities; Provision of acoustic barriers or shelters in noisy workplaces; Provision of hoods to noise generating equipment like pumps; Provision of thick greenbelt to attenuate noise levels; Provision of Personal Protective Equipments (PPE) such as earplugs, earmuffs to the workers working in high noise level area; and Implementation of greenbelt, landscaping with horticulture at power block areas to reduce noise impacts Solid Waste Management Solid waste in the form of ash will be generated in a coal based thermal power plant. The total ash generated in the plant will be MTPA out of which 80% will be fly ash i.e MTPA and balance will be bottom ash of MTPA. The following measures shall be taken for solid waste management: In general, ash will be given to potential ash users; The excess ash will be disposed of using high concentrated slurry disposal system to HDPE lined ash dyke; The generated waste oil shall be explored to be used in boiler furnace with HFO or shall be given to authorized recyclers; Solid waste generated in the Sewage Treatment Plant (STP) will be used as manure in greenbelt development; and Maintaining the data base on solid waste generation such as quantity, quality, treatment / management. VIMTA Labs Limited, Hyderabad 137

148 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Literature on Fly Ash Utilization Fly Ash use in Cement Industries Cement mixed with fly ash is known as Portland Pozzolana Cement (PPC). As per the Indian standards, fly ash can be used to replace 25% to 35% cement. The fly ash cement is made by grinding with clinker. The fly ash generated from plant will be supplied to cement plants in the region. The fly ash can be utilized by these cement plants to manufacture PPC cement. Fly Ash use in Road Construction Fly ash can be used as a component in a stabilized aggregate sub-base course. A blend of 84% dense aggregate, 11% fly ash and 5% hydrated lime gives maximum dry density, optimum moisture content and unconfined compressive strength Prospective Ash Utilization It is very much clear that the ash generated at the power plants can be effectively used for various products. Though the acceptability of the ash-based products may take a long time, it is always better to start on a small scale. The figures derived at about the ash utilization in the area are only rough estimates and may be considered as a guideline. The probable ash utilization quantities estimated in the earlier sections are tabulated in the following Table TABLE-4.9 SELECTED AREAS OF FLY ASH UTILIZATION All values except percentage are in MTPA Sr. No. Item Description 1 st 2 nd 3 rd 4 th year year year year 1 Total production of fly ash Use in brick plants Fly ash use in micro nutrition as fertilizers Use in fly ash in clay brick Road development in surrounding areas Use of pozzolonic material cement (PPC) Total fly ash consumption Percentage of use of fly ash (%) Note: The figures derived above the ash utilization in the area are only rough estimates and may be considered as a guideline only. VIMTA Labs Limited, Hyderabad 138

149 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Policy on Fly Ash Utilization Utilization of ash produced by coal based power stations as a thrust area of its activities and all possible actions will be taken to enhance level of ash utilization. Various avenues for ash utilization will be explored as delineated in the above sections. In particular, supply of quality ash for manufacture of cement will be taken as there are some cement units. Some of the actions planned for the project are as given below: ARS will make efforts to motivate and encourage entrepreneurs to set up units for manufacture of ash-based products such as fly ash bricks, lightweight aggregates, cellular concrete products etc., as ancillary industries in the region. ARS would be providing all possible infrastructure facilities to these entrepreneurs in accordance with its policy; ARS will also continue to encourage utilization of available ash based products in all its erection activities; and ARS will encourage the use of water treated fly ash as a soil ameliorator and as a source of micro-nutrients and secondary nutrients for improving agricultural productivity. All efforts will be made for 100% utilization of fly ash. ARS is committed to comply with the Fly Ash Utilization Notification, 1999 and as amended thereof Excess ash Disposal The balance ash after utilisation shall be disposed in ash dyke. Ash disposal system proposed is High Concentrate Slurry Disposal (HCSD). Treated wastewater will be used in ash handling plant. The ash dyke will be provided with HDPE liners. The area provided for ash dyke is about 3.25 ha. The major advantages of the HCSD method are: Very low water consumption; The slurry can be self-setting and self-limiting so that ash will deposit and dry by itself to form a hard surface; Considerably less area is required for ash disposal; Specific energy consumption in pumping and transportation will be much lower; VIMTA Labs Limited, Hyderabad 139

150 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Pipeline diameter can be much smaller and transportation velocities could also be considerably lower due to the fact that the slurry is non-settling. This could also reduce wear in the pipeline; Both bottom ash and fly ash can be disposed together if needed; and The trenches will be constructed along the periphery of the ash dyke to collect the run-off water during rainy days. The run-off water will be routed through sedimentation tank before discharging. The ash will be utilized in various construction materials to the maximum extent and 100% utilization will be achieved. 4.6 Greenbelt Development With rapid industrialization and consequent deleterious impact of pollutants on environment, values of environmental protection offered by trees are becoming clear. Trees are very suitable for detecting, recognizing and reducing air pollution effects. Monitoring of biological effects of air pollutant by the use of plants as indicators has been applied on local, regional and national scale. Trees function as sinks of air pollutants, besides their bio-esthetical values, owing to its large surface area. The greenbelt development not only functions as foreground and background landscape features resulting in harmonizing and amalgamating the physical structures of the plant with surrounding environment, but also acts as pollution sink. Thus, implementation of afforestation program is of paramount importance. It will also check soil erosion, make the ecosystem more complex and functionally more stable and make the climate more conducive. The existing plant has a greenbelt area of ha (25.53 acres). Additionally 2.97 ha (7.34 acres) of greenbelt will be developed for the expansion. Greenbelt with a width of 50 m to 100 m will be developed around the proposed plant site. The total greenbelt around the power plant complex will be about ha (32.86 acres) covering 35.96% of the total plant area after expansion Species for Plantation The species proposed will have broad leaves. Trees will be selected based on the type of pollutants, their intensity, location, easy availability and suitability to the local climate. They have different morphological, physiological and bio-chemical mechanism/ characters like branching habits, leaf arrangement, size, shape, surface (smooth/hairy), presence or absence of trichomes, stomatal conductivity proline content, ascorbic acid content, cationic peroxides and sulphite oxidize activities etc., to trap or reduce the pollutants. VIMTA Labs Limited, Hyderabad 140

151 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures Species to be selected will fulfil the following specific requirements of the area: Tolerance to specific conditions or alternatively wide adaptability to ecophysiological conditions; Rapid growth; Capacity to endure water stress and climate extremes after initial establishment; Differences in height and growth habits; Pleasing appearances; and Providing shade. 4.7 Cost Provision for Environmental Measures It is proposed to invest about INR. 360 Crores in addition to the existing facilities on pollution control, treatment and monitoring systems for proposed activity. In addition to this, INR. 1.0 Crores per annum will be spent on greenbelt maintenance in and around the proposed additional area. The break-up of the investment is given in Table Sr. No. TABLE-4.10 COST PROVISION FOR ENVIRONMENTAL MEASURES Description of item Capital Cost (INR in Crores) Recurring Cost (Rs in Crores/annum) 1 Raw water treatment systems Wastewater treatment systems Rainwater harvesting systems Air pollution control systems including ESP 5 Stack (220 m height) Noise pollution control systems Environmental monitoring/ Environmental Laboratory 8 Occupational health & safety Greenbelt development Total VIMTA Labs Limited, Hyderabad 141

152 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures 4.8 Corporate Social Responsibility ARS has always believed that managing its business most efficiently and in a cost effective manner is its primary duty to the society. ARS also believes that it can contribute to the common cause of the society by bringing in the same level of corporate efficiency in the administration and management of the various CSR initiatives. ARS have provided bore wells in the villages for drinking water. ARS is in discussion to engage a full time NGO for the social upliftment of the villages by identifying the necessary programs in consultation with village leaders. Also have discussed with district administration (District Rural Development Authorities - DRDA) for implementing SSS (Self Service Scheme Namakku Name Thittam) The proposed schemes include 1. Vocational training program; 2. Road laying; 3. Toilet facilities; 4. Drinking water facilities; 5. Cattle for generating livelihood; and 6. Setting up of primary schools. TABLE 4.11 (a) EXPENSES TOWARDS CSR Sr. No. Description Amount Spent in INR. 1 Housing aid to the nearby communities 23,54,694/- 2 Upgradation of nearby village school from 8 th std to 10 th std. 9,73,396/- 3 Drinking water facilities to nearby schools 1,81,501/- 4 Construction of first aid centre with doctor facilities at Eguvarapalayam village 6,40,315/- Amount spent for construction of 5 compound water to the local panchayat 3,00,000/- school Total 44,49,906/- VIMTA Labs Limited, Hyderabad 142

153 district, Tamilnadu Chapter 4 Anticipated environmental impacts and mitigation measures TABLE 4.11 (b) EXPENSES TOWARDS CSR Corporate social responsibility - upto cod - aug'13 Description Actuals (rs) Description Actuals (rs) School uniform 10,178 Ambulance 463,396 School books 553,600 Diesel & maintenance School function Water pumps 60,000 Computers 53,808 Bore well 257,274 Printers 30,000 RO. Plant - village 45,000 Toilets Maintenance of RO plant RO. Plant Public toilets 360,600 Maintenance of RO plant Road 2,500,000 Teacher's salary Sports development 100,000 Medicine 113,500 Hospital 100,000 School sports 25,785 Temple 53,200 School prizes 100,000 Panchayat 19,252 Stationery 63,970 Police station 10,600 Furnitures 600,000 People welfare (saris) 40,000 School maintenance 44,463 EB 2,250 Sieving machines 63,500 School boundary 1,306,000 Drains Water coolers & RO for school 70,000 Development of lab in school 180,300 Total (rs) Rs.16,58,804 Total Rs.55,67,872 VIMTA Labs Limited, Hyderabad 143

154 District, Tamilnadu Chapter 5 Analysis of alternatives (technology and site) 5.0 ANALYSIS OF ALTERNATIVES (TECHNOLOGY AND SITE) 5.1 Analysis of alternative sites for location of power plant The proposed site acquired for the additional unit (1 x 350 MW) is adjacent to the existing plant site of ARS. The adjacent land has been selected based on the following criteria Availability of barren land adjacent to existing site No forest land No crop land Nearest village (Siruvapuri) is more than 1 km Accessibility to railway line Coal transportation Absence of ecologically / environmentally sensitive areas within 15 km radius National highway (NH 5) is 4.8 km from plant site Manpower availability from nearby areas Based on the above criterion, alternate site analysis is not required for the current expansion activity as the adjacent site is the most viable option for this project. 5.2 Analysis of Alternative for Unit Size Selection Unit Size Selection The most suitable unit size for the proposed boliers for 1 x 135 MW & 1 x 350 MW has been considered by analysing various major aspects as enumerated below: i) Provenness based on the quality of main fuel to be fired; ii) Reliability and availability; iii) Capacity of the grid for evacuation of power; iii) Capital expenditure and economics of power generation; iv) Space requirement; iv) Manpower requirement. Provenness The TG units and matching Coal fired boilers of both the sizes (135 MW and 350 MW) are well tested in India as well as abroad. Both 1x135 MW and 1 x 350MW are comparable in this aspect. Reliability and availability Reliability of 135 MW and 350 MW steam generator and turbo generator are comparable. VIMTA Labs Limited, Hyderabad / Coimbatore 145

155 District, Tamilnadu Chapter 5 Analysis of alternatives (technology and site) Dependence on the grid The dependence on grid for drawal of power, with 1 x 135 & 1 x 350 MW will be higher when compared to four or more unit configurations. Space requirement The space requirement will be marginally less for 1 x 350 MW power station as compared to the space required for more unit configurations. Manpower requirement The manpower requirement with four units station will be around 20% higher compared to two unit station. This is due to the fact that in 4 unit configuration, number of plant and equipment will increase. Capital expenditure and economics of power generation The capital expenditure of 4 unit station will be around 7-10% higher compared to 2 unit station. The generation cost also will be higher for 4 unit configuration power plant due to higher capital cost, marginally higher heat rate and more expenditure towards O&M. Analysis From the foregoing it could be seen that both the unit sizes have their own advantages and disadvantages. It is true that capital expenditure and cost of power generation both will be less in case of 1 x 135 MW & 1 x 350 MW power plants. Recommendation on selection of unit size From the foregoing, it could be seen that for the 2 - unit configuration capital cost and cost of power generation both will be less as compared to 4 - unit configuration. However, with 2 unit configuration, during planned / forced outage loss of one unit generation will lead less power sale resulting in reduced revenue during the unit shutdown period. Selection of 1 x 135 & 1 X 350 MW unit configuration is recommended. Conclusion and Recommendation: Overall Recommendation Based on the foregoing it is recommended to go in for 1 x 135 & 1 X 350 MW configuration power plant based on PF boilers. VIMTA Labs Limited, Hyderabad / Coimbatore 146

156 district, Tamilnadu Chapter 6 Environmental monitoring program 6.0 ENVIRONMENTAL MONITORING PROGRAM 6.1 Introduction Regular monitoring of environmental parameters is of immense importance to assess the status of environment during project its operation phase. With the knowledge of baseline conditions, the monitoring programme will serve as an indicator for any deterioration in environmental conditions due to operation of the project, to enable taking up suitable mitigatory steps in time to safeguard the environment. Monitoring is as important as that of control of pollution since the efficiency of control measures can only be determined by monitoring. Usually, as in the case of the study, an impact assessment study is carried over short period of time and the data cannot bring out all variations induced by the natural or human activities. Therefore, regular monitoring programme of the environmental parameters is essential to take into account the changes in the environmental quality. 6.2 Implementation Schedule of EMP The mitigation measures suggested in the Chapter-4 will be implemented so as to reduce the impact on environment due to the operations of the plant operation. In order to facilitate easy implementation, mitigation measures are phased as per the priority implementation. The priority of the implementation schedule is given in Table-6.1. TABLE-6.1 EMP IMPLEMENTATION SCHEDULE Sr. No. Recommendations Requirement 1 Air pollution control measures Before commissioning 2 Water pollution control measures Before commissioning 3 Noise control measures Along with the commissioning of the Project 4 Solid waste management During commissioning of the project 5 Green belt development Stage-wise implementation 6.3 Environmental Monitoring and Reporting Procedure Regular monitoring shall check whether the commitments proposed are being met. This may take the form of direct measurement and recording of quantitative information, such as amounts and concentrations of discharges, emissions and wastes, for measurement against corporate or statutory standards, consent limits or targets. It may also require measurement of ambient environmental quality in the vicinity of a site using ecological/biological, physical and chemical indicators. Monitoring may include socio-economic interaction, through local liaison activities or even assessment of complaints. VIMTA Labs Limited, Hyderabad/Coimbatore 147

157 district, Tamilnadu Chapter 6 Environmental monitoring program Objectives of Monitoring The objectives of environmental post-project monitoring are to: Verify effectiveness of planning decisions; Measure effectiveness of operational procedures; Confirm statutory and corporate compliance; and Identify unexpected changes. 6.4 Monitoring Schedule Environmental monitoring schedules are prepared covering various phases of project advancement, such as erection phase and regular operational phase Monitoring Schedule during constructional phase The proposed expansion envisage setting up of boilers, turbines and establishment of storage facilities for coal and ash. The construction activities require preparing land, mobilisation of construction material and equipment to plant site. The generic environmental measures that need to be undertaken during project construction stage are given in Table-6.2. TABLE-6.2 ENVIRONMENTAL MONITORING DURING PROJECT CONSTRUCTION STAGE Sr. Potential Action to be Followed No. Impact 1 Air Emissions All equipment to be operated within specified design parameters Vehicle trips to be minimized to the extent possible Maintenance of DG set emissions to meet stipulated standards Ambient air quality within the premises of the plant area to be monitored 2 Noise List of all noise generating machinery onsite along with age to be prepared Parameters for Monitoring Random checks of equipment logs/ manuals Vehicle logs Gaseous emissions (SO 2, HC, CO, NO x) The ambient air quality will conform to the standards for PM 10, PM 2.5, SO 2, NO x, and CO Equipment noise reading logs, Frequency of Monitoring Periodic Periodic during site clearance & construction activities Periodic emission monitoring As per CPCB / SPCB requirement or on monthly basis whichever is earlier Regular during construction activities Equipment to be maintained in good working order Night working is to be minimized. Generation of vehicular noise Working hour records Maintenance of records of vehicles Daily records Daily records VIMTA Labs Limited, Hyderabad/Coimbatore 148

158 district, Tamilnadu Chapter 6 Environmental monitoring program Sr. No. Potential Impact 3 Wastewater Discharge Action to be Followed Noise to be monitored in ambient air within the plant premises No untreated discharge to be made to surface water, groundwater or soil 4 Soil Erosion Protect topsoil stockpile where possible at edge of site 5 Drainage and effluent Management Ensure drainage system and specific design measures are working effectively Parameters for Monitoring Frequency of Monitoring Spot Noise recording As per CPCB/SPCB requirement or on quarterly basis whichever is earlier No discharge hoses Periodic during shall be in vicinity of construction watercourses activities Effective cover in place Visual inspection of drainage and records thereof Periodic during construction activities Periodic during construction activities 6 Waste Management The design to incorporate existing drainage pattern and avoid disturbing the same Implement waste management plan that identifies and characterizes every waste arising associated with proposed activities and which identifies the procedures for collection, handling & disposal of each waste arising. 7 Non-routine Plan to be drawn up, events and considering likely accidental emergencies and steps releases required to prevent/limit consequences 8 Health Employees and migrant labour health check ups 9 Environmental Management Cell/ Unit 10 Loss of flora and fauna The Environmental Management Cell/Unit is to be set up to ensure implementation and monitoring of environmental safeguards Re-vegetation as per Forest guidelines Comprehensive Waste Management Plan should be in place and available for inspection onsite Compliance with MSW Rules, 1998 and Hazardous Wastes (Management and Handling Rules), 2003 Mock drills and records of the same All relevant parameters including HIV Responsibilities and roles will be decided before the commencement of work No. of plants, species Periodic check during construction activities Periodic during construction activities Regular ups During construction phase During clearance check site VIMTA Labs Limited, Hyderabad/Coimbatore 149

159 district, Tamilnadu Chapter 6 Environmental monitoring program Monitoring Schedule during Operational Phase During operational stage, continuous air emissions from power boilers, wastewater disposal to river, non-hazardous waste such as ash, hazardous used oily wastes are expected. The following attributes which merit regular monitoring based on the environmental setting and nature of project activities are listed below: Source emissions and ambient air quality; Groundwater levels and ground water quality; Water and wastewater quality (water quality, effluent & sewage quality etc); Solid and hazardous waste characterisation (fly ash, bottom ash, oily wastes, ETP sludge, used and waste oil); Soil quality; Noise levels (equipment and machinery noise levels, occupational exposures and ambient noise levels); and Ecological preservation and afforestation. The following routine monitoring programme as detailed in Table-6.3 shall be implemented at site. Besides to this monitoring, the compliances to all environmental clearance conditions and regular permits from SPCB/MoEF shall be monitored and reported periodically (once every six months). TABLE-6.3 ENVIRONMENTAL MONITORING DURING OPERATIONAL PHASE Sr. Potential Action to be Followed No. Impact 1 Air Emissions Stack emissions from power boilers to be optimized and monitored Stack emissions from DG set to be optimized and monitored Ambient air quality within the premises of the plant and nearby habitations to be monitored Exhaust from vehicles to be minimized by use of fuel efficient vehicles and well maintained vehicles having PUC certificate Measuring onsite data of Meteorology Parameters for Monitoring Gaseous emissions (PM 10, PM 2.5, PM size distribution, SO 2, CO, NO x) Gaseous emissions (SO 2, HC, CO, NO x) PM 10, PM 2.5, SO 2, NO x, O 3, CO, Lb, As, Ni, C 6H 6, B(a)P, NH 3 and Hg Vehicle logs to be maintained Wind speed, direction, temp., relative humidity and rainfall, solar radiation Frequency of Monitoring Continuous monitoring using on-line equipment during entire operation phase Periodic during entire operation phase As per CPCB/ SPCB requirement or on weakly basis whichever is earlier Continuous monitoring using on-line weather station during operation phase VIMTA Labs Limited, Hyderabad/Coimbatore 150

160 district, Tamilnadu Chapter 6 Environmental monitoring program Sr. Potential Action to be Followed No. Impact 2 Noise Noise generated from operation of power boilers to be optimized and monitored Parameters for Monitoring Spot Noise Level recording; L eq (night), L eq (day), L eq (dn) Frequency of Monitoring Once every six months 3 Wastewater Discharge 4 Drainage and effluent Management Noise generated from operation of DG set to be optimized and monitored and should be provided with acoustic enclosures Generation of vehicular noise Wastewater (treated and untreated) analysis Ensure drainage system and specific design measures are effective & working Noise levels to be recorded at 1m distance from the respective unit Maintain records of vehicles As per CPCB Visual inspection of and cleaning of drainage before monsoon season Periodic during operation phase Once in a month Periodic during operation phase 5 Water Quality and Water Levels Design to incorporate existing drainage pattern and avoid disturbing the same Monitoring of groundwater quality around ash pond and ground water levels Comprehensive monitoring as per IS: Once in a month River water quality downstream to discharge Groundwater level in meters bgl As per IS: (2012) Water level maintaining once every season Once in a month 6 Emergency preparedness, such as fire fighting Fire protection and safety measures to take care of fire and explosion hazards, to be assessed and steps taken for their prevention 7 Maintenance of Vegetation, greenbelt / flora and fauna green cover development 8 Waste Implement waste Management management plan that identifies and characterizes every waste arising associated with the plant activities and which identifies the procedures for collection, handling & disposal of each waste arising 9 Soil quality Maintenance of good soil quality 10 Health Employees and migrant labour health check ups Mock drill records, on site emergency plan, evacuation plan No. of plants, species Records of solid waste generation, treatment and disposal Physico-chemical parameters and metals. All relevant parameters Periodic during operation phase Once in summer and winter Periodic during operation phase Periodical monitoring at ash dyke Regular checkups VIMTA Labs Limited, Hyderabad/Coimbatore 151

161 district, Tamilnadu Chapter 6 Environmental monitoring program 6.5 Monitoring Methods and Data Analysis of Environmental Monitoring All environmental monitoring and relevant operational data will be stored in a relational database and should be able to link to GIS system. This will enable efficient retrieval and storage and interpretation of the data. Regular data extracts and interpretive reports will be sent to the regulator Air Quality Monitoring and Data Analysis Stack Monitoring The emissions from all the stacks shall be monitored regularly. The exit gas temperature, velocity and pollutant concentrations shall be measured. Any unacceptable deviation from the design values shall be thoroughly examined and appropriate action shall be taken. Air blowers shall be checked for any drop in exit gas velocity Workspace Monitoring The concentration of airborne pollutants in the workspace/work zone environment shall be monitored periodically. If concentrations higher than threshold limit values are observed, the source of fugitive emissions shall be identified and necessary measures shall be taken. Methane and non-methane hydrocarbons shall be monitored in oil storage area once in a season. If the levels are high, suitable measures as detailed in EMP shall be initiated Ambient Air Quality Monitoring The ground level concentrations of PM 10, PM 2.5, SO 2 and NO X in the ambient air shall be monitored at regular intervals. Any abnormal rise shall be investigated to identify the causes and appropriate action shall be initiated. Greenbelt shall be developed for minimising dust propagation. The ambient air quality data should be transferred and processed in a centralised computer facility equipped with required software. Trend and statistical analysis should be done Water and Wastewater Quality Monitoring and Data Analysis To ensure a strict control over the water consumption, flow meters shall be installed for all major inlets. All leakages and excess shall be identified and rectified. In addition, periodic water audits shall be conducted to explore further possibilities for water conservation. Methods prescribed in "Standard Methods for Examination of Water and Wastewater" prepared and published jointly by American Public Health Association (APHA), American Water Works Association (AWWA) is recommended Monitoring of Wastewater Streams All the wastewater streams in the project area shall be regularly analysed for flow rate, physical and chemical characteristics. VIMTA Labs Limited, Hyderabad/Coimbatore 152

162 district, Tamilnadu Chapter 6 Environmental monitoring program Such analysis is carried out for wastewater at the source of generation, at the point of entry into the wastewater treatment plant and at the point of final discharge. These data shall be properly documented and compared against the design values for any necessary corrective action Monitoring of Groundwater The monitoring of groundwater is the most important tool to test the efficiency of ash pond performance. This is indispensable as it provides detection of the presence of waste constituents in groundwater in case of leachate migration. In this programme, water samples are taken at a predetermined interval and analysed for specific pollutant expected to be in the leachate. For early detection of leachate migration, if any, it is suggested to construct piezometers around the ash dyke. In addition to piezometers, monitoring wells should be installed to a depth of at least 3-m below the maximum historic groundwater depth. Based on assumptions and data about the characteristics of leachate to be generated, approximate permeability of soils in the zone of aeration and direction and velocities of groundwater flow, the maximum probable aerial extent of contaminant migration can be estimated as a basis for establishing the position of monitoring wells. A minimum of two ground monitoring wells should be typically installed at ash disposal facility: one up-gradient well and one down-gradient well. It is suggested to collect water samples and analyse. Records of analysis should be maintained Noise Levels Noise levels in the work zone environment such as boiler house, cooling tower area, DG house shall be monitored. The frequency shall be once in three months in the work zone. Similarly, ambient noise levels near habitations shall also be monitored once in three months. Audiometric tests should be conducted periodically for the employees working close to the high noise sources. 6.6 Reporting Schedules of the Monitoring Data It is proposed that voluntary reporting of environmental performance with reference to the EMP should be undertaken. The environmental monitoring cell shall co-ordinate all monitoring programmes at site and data thus generated shall be regularly furnished to the state/central regulatory authorities. The frequency of reporting shall be on once every six months to the local state PCB officials and to Regional office of MoEF. The Environmental Audit reports shall be prepared for the entire year of operations and shall be regularly submitted to regulatory authorities. VIMTA Labs Limited, Hyderabad/Coimbatore 153

163 district, Tamilnadu Chapter 6 Environmental monitoring program 6.7 Infrastructure for Monitoring of Environmental Protection Measures A well-equipped laboratory with consumable items shall be provided for monitoring of environmental parameters in the site. Alternatively, monitoring can be outsourced to a recognized accredited laboratory. The following equipment and consumables shall be made available in the site for environmental monitoring or alternatively the monitoring can be outsourced to a recognized accredited laboratory. Air quality and meteorology High volume samplers, stack monitoring kit, personal dust sampler, central weather monitoring station, spectrophotometer (visible range), single pan balance, flame photometer, relevant chemicals as per IS:5182. Water and wastewater quality The sampling shall be done as per the standard procedures laid down by IS:2488. The equipments and consumables required are: BOD incubator, COD reflex set-up, refrigerator, oven, stop watch, thermometer, ph meter, distilled water plant, pipette box, titration set, dissolved oxygen analyser and essential chemicals. Noise levels Noise monitoring shall be done utilising an integrating sound level meter to record noise levels in different scales like A-weighting with slow and fast response options. VIMTA Labs Limited, Hyderabad/Coimbatore 154

164 district, Tamilnadu Chapter 8 Project benefits 8.0 PROJECT BENEFITS 8.1 Introduction Proposed expansion of the power plant will result in a considerable growth in industrial and commercial sector in the state. Small and medium scale industries may be further developed as a consequence. Proposed expansion would be beneficial in reducing the existing and ever escalating demand of electricity in the southern part of the country. In operation phase, the plant would require significant workforce of non-technical and technical persons. Migration of persons with better education and professional experience will result in increase of population and literacy in the surrounding villages Availability of Quality Power The plant would be generating about 545 MW of power after the current expansion and this project is inline with the central government s massive power capacity addition plan, which sets a target of adding 88,537 MW of power generation capacity in the country in the 12 th plan ( ) as per the report of Integrated Resource Planning Division, Planning wing, CEA Improvements in the Physical Infrastructure The beneficial impact of the power plant on the civic amenities will be substantial after the commencement of project activities. The basic requirement of the community needs will be strengthened by extending healthcare, educational facilities to the community, building/strengthening of existing roads in the area. ARS will initiate the above amenities either by providing or by improving the facilities in the area, which will help in uplifting the living standards of local communities Improvement in the Social Infrastructure Generation of employment: The project will create direct and indirect employment opportunities; Increase in purchasing power and improved standard of living of the area; Further development of small and medium scale industries may be developed as consequence; Increased revenue to the state by way of royalty, taxes and duties; Overall growth of the neighboring area viz.: Health and family welfare; Watershed development; VIMTA Labs Limited, Hyderabad/Coimbatore 189

165 district, Tamilnadu Chapter 8 Project benefits Sustainable livelihood and strengthening of village Self Help Groups; and Infrastructure development. In addition to above, due to increase in purchasing power of local habitants: There shall be significant change in the socio-economic scenario of the area; The proposed expansion shall enhance the prospects of employment; Recruitment for the unskilled and semiskilled workers for the proposed project will be from the nearby villages; The basic amenities viz. roads, transportation, electricity, proper sanitation, educational institutions, medical facilities, entertainment, etc., will be developed as far as possible; and Overall the project will change living standards of the people and improve the socio-economic conditions of the area Employment Potential The impact of the project on the economic aspects can be clearly observed. The project activities will provide employment to persons of different skills and trades. The local population will be given preference to employment. The employment potential will ameliorate economic conditions of these families directly and provide employment to many other families indirectly who are involved in business and service oriented activities. The employment of local people in primary and secondary sectors of project shall upgrade the prosperity of the region. This in-turn will improve the socio-economic conditions of the area. During construction phase of the project, this project will provide temporary employment to many unskilled and semi-skilled laborers in nearby villages. This project will also help in generation of indirect employment to those people who render their services for the personnel directly working in the project; and During operational phase, considerable number of people will be benefited by provision of services. Thus, the direct and indirect employment generation by this plant expansion. The trend of out migration for employment, if any, is likely to be reduced due to better economic opportunities available in the area. During the erection phase, about 50 people on average will be employed. The additional manpower of power plant during operational period is estimated to be about 200 persons. VIMTA Labs Limited, Hyderabad/Coimbatore 190

166 district, Tamilnadu Chapter 9 Administrative aspects 9.0 ADMINISTRATIVE ASPECTS 9.1 Institutional Arrangements for Environment Protection and Conservation Environment Management cell is being headed by a senior manager and will constitute environmental engineer, scientists, chemists and supervisors. The Organizational Structure of Environment Management is presented in Figure-9.1. The Manager (Env) will be responsible for Environment management activities. Basically, this department will supervise the monitoring of environmental pollution levels viz. source emission monitoring, ambient air quality, water and effluent quality, noise level either departmentally or by appointing external agencies wherever necessary. In case the monitored results of environmental pollution found to exceed the allowable limits, the Environmental Management Cell will suggest remedial action and get these suggestions implemented through the concerned authorities. The Environmental Management Cell also co-ordinates all the related activities such as collection of statistics of health of workers and population of the region, afforestation and greenbelt development. VIMTA Labs Limited, Hyderabad / Coimbatore 191

167 district, Tamilnadu Chapter 9 Administrative aspects GENERAL MANAGER (O & M) DY. GENERAL MANAGER (O & M) MANAGER (ENVIRONMENT) SAFETY OFFICER ENVIRONMENT ENGINEER ECOLOGIST/ HORTICULTURIST CHEMISTS SUPPORT STAFF FIGURE-9.1 ORGANIZATIONAL STRUCTURE OF ENVIRONMENT MANAGEMENT VIMTA Labs Limited, Hyderabad / Coimbatore 192

168 district, Tamilnadu Chapter 10 Summary and conclusion 10.0 SUMMARY AND CONCLUSION 10.1 Identification of project and project proponent ARS, a pioneer in the field of manufacturing TMT re-bars and Mild Steel Billets intends an expansion & augmentation of its existing coal based thermal power plant at Sithurnatham, Sirupuzhalpettai & Eguvarapalayam villages, Gummidipoondi village, Thiruvallur district, Tamil Nadu. The cost of the total project is about INR crores, which includes INR. 360 Crores for environmental protection measures Environmental setting of the site The study area map of 10 km radius around the plant site is given in Figure The environmental setting of the plant site is given as follows: TABLE 10.1 ENVIRONMENTAL SETTING OF THE PLANT Sr. No. Particulars Details 1 Site-coordinates Refer Figure-1.3 (Chapter 1) 2 Elevation 18.0 m AMSL 4 Climatic conditions (Plant site) 1 st May to 31 st July 2014 a. Max. Temp: C b. Min. Temp: C c. Rainfall: mm 5 Land use Industrial 6 Nearest highway NH km, East 7 Nearest railway station Gummidipoondi R.S. 6.1 km, ESE 8 Nearest airport Anna International Airport, Chennai 48.3km, SSE 9 Nearest habitations Chitoornatham 0.5 km, West Eguvarpalayam 1.7 km, NNW 10 Densely populated area Chennai city 44.7 km, SSE 11 Inland water bodies Chittoornatham pond 1.0 km, West Pulicat lake 8.1 km, NE Arani river 7.4 km, SSE Pallavada lake 6.6 km, NW 12 Ecologically sensitive zones like Nil Wild Life Sanctuaries, National Parks and biospheres 13 Defense establishments None within 10 km radius 14 Socio-economic factors No Resettlement and Rehabilitation issues 15 Seismicity zone Zone III as per IS: 1893 (Part-1) Nearest sea coast Bay of Bengal 26.7 km, East 17 Reserve forests Puliyur forest 3.1 km, SSW Periyapuliyur forest 4.3 km, SW Pallavakam R.F. 5.6 km WSW Thervoy R.F. 5.7 km, SW Manali R.F. 5.7 km, SSW Siruvada forest 8.2 km, WSW Palem forest 12.3 km, WNW 18 Historical / archaeological Nil within 15.0 km from project boundary places VIMTA Labs Limited, Hyderabad 193

169 district, Tamilnadu Chapter 10 Summary and conclusion FIGURE KM RADIUS STUDY AREA OF THE PROJECT SITE VIMTA Labs Limited, Hyderabad 194

170 district, Tamilnadu Chapter 10 Summary and conclusion 10.2 Details of the proposed project The proposed expansion will be operated on coal as main fuel to generate 545 MW of power. The details of the project are given in Table TABLE-10.2 SALIENT FEATURES OF THE PROPOSED PROJECT Sr. No. Features Description 1 Total capacity 545 MW 2 Configuration Under operation: 1 x 60 MW Proposed: 1 x 135 MW + 1 X 350 MW 3 Technology 1 X 60 MW & 1 X 135 MW PF Boiler with re-heat cycle: M.S: 170 kg/cm 2 / 537 O C; Reheat: 537 O C 1 X 350 MW Super Critical PF Boiler with re-heat cycle: M.S: 255 kg/cm 2 / 585 O C; Reheat: 585 O C 4 Boilers 1 x TPH; Sub critical (Existing 1 x 60 MW) 1 x 563 TPH; Sub critical (Proposed 135 MW) 1 x 950 TPH; Super critical (Proposed 350 MW) CFBC/Pulverized Coal fired, natural circulation boilers 5 Generators Three generators with rated 60 MW, 11KV, 50 Hz, 3 ph and 0.8 PF, 135 MW & 350 MW 6 Power evacuation Power evacuation will be from Thervaikandigai, which is located 14.0 km from site 7 Condenser Air cooled condenser 8 Auxiliary Cooling System Finfan coolers for cooling of turbine, generator and boiler auxiliaries 9 HFO/LDO Storage 2 x 300 KL HFO tanks and 2 x 150 KL LDO tanks Tanks 10 Switchyard, 230 KV System Generator, Transformer and Station Transformer 11 Fuel Coal 12 Source of Coal Indonesia Coal (Imported) 13 Coal Handling Ground hoppers, stacker, reclaimers and double stream conveying system 14 Coal Requirement 2.31 MTPA at 85% PLF 15 Sulphur content 0.5% 16 Ash Content in Coal 9.0% 17 Ash generation Bottom Ash Fly Ash MTPA MTPA MTPA A B 18 Ash Handling Dry ash collection 19 ESP efficiency 99.99% 20 Stack 145 m AGL [Common for 1 x 60 MW & 1 X 135 MW] 220 m AGL [Common for 1 x 350 MW] 21 Total water demand 240 KLD (0.098 cusec) 22 Source of water Existing borewells 23 Project cost INR Crores VIMTA Labs Limited, Hyderabad 195

171 district, Tamilnadu Chapter 10 Summary and conclusion Technology and process description The existing 60 MW and the proposed 135 MW power plant will be a conventional thermal power plant operating on sub critical pressure, single reheat steam cycle with regenerative feed heating arrangement. The primary fuel to be used for the power generation will be coal. The mode of transportation of coal will be by road from Ennore port. The superheated steam from the boilers at 170 bar and 537ºC is supplied to the High Pressure (HP) turbine. This steam, after expansion in the HP turbine is sent back to the boiler as cold reheat steam. After reheating in the boiler, the reheated steam (Hot reheat steam) at about 42 bar and 537 ºC is sent to Intermediate Pressure (IP) and Low Pressure (LP) turbine and is finally exhausted into the condenser. The exhaust steam is cooled and condensed in an air cooled condenser. The proposed 1 X 350 MW will be operated on Super critical pressure PF Boiler with re-heat cycle: M.S: 255 kg/cm 2 / 585 O C; Reheat: 585 O C Power evacuation Power evacuation will be from Thervaikandigai, which is located 14.0 km from site Land requirement The existing plant operates in an area of ha (62.99 acres). Additionally ha (28.39 acres) of barren land has been acquired for the current expansion activities. Totally the plant after expansion operates in an area of ha (91.38 acres) Fuel Requirement The primary fuel of the power plant will be 100% Indonesian coal. The maximum total annual coal consumption for the power plant after expansion will be about 2.31 MTPA. Coal from Indonesia would be transported through sea to Ennore port and thereon through trucks to the existing plant site Water Requirement The total water demand for the plant after expansion will be about 240 KLD, which will be met from existing borewells and rain water harvesting Manpower The total manpower of the existing plant is about 150 employees. Upon expansion, additional 200 employees will be required, which includes officers and supervisors also. VIMTA Labs Limited, Hyderabad 196

172 district, Tamilnadu Chapter 10 Summary and conclusion 10.3 Baseline Environmental Status The 10 km radial distance from the existing plant boundary has been considered as study area for Environmental Impact Assessment (EIA) baseline studies. Environmental monitoring for various attributes like meteorology, ambient air quality, surface and ground water quality, soil characteristics, noise levels and flora & fauna have been conducted at specified locations and the secondary data collected from various Government and Semi-Government organizations. The baseline environmental monitoring studies were carried out from 1 st May 2014 to 31 st July Land Use The land use pattern of the study area has been studied by analyzing the available secondary data published in the District Primary Census abstract of the year In addition to the establishment of land use pattern based on the review of secondary data, the land use pattern in study area and its buffer zones covered within a radius of 10 km from the existing plant has been established through interpretation of satellite imageries and by means of preparation of land use/land cover map Meteorology On-site monitoring was undertaken for various meteorological parameters in order to generate the site-specific data. Data was collected every hour continuously from 1 st May to 31 st July The maximum and minimum temperatures recorded at the site during the study period are 43.0 o C and C. The humidity found varying from 18% to 100%. The predominant winds are mostly from West (18.5%) followed by South (14.6%). Calm conditions were recorded for 3.34% Ambient Air Quality To establish the baseline status of the ambient air quality in the study area, the air quality was monitored at 8 locations. The summary of the Ambient Air Quality monitored is given in Table TABLE SUMMARY OF AMBIENT AIR QUALITY IN THE STUDY AREA PM 2.5 PM 10 SO 2 NO x CO Concentrations are expressed in g/m 3 The results of the monitored data indicate that the ambient air quality of the region in general is in conformity with respect to rural/residential norms of National Ambient Air Quality standards of CPCB, with present level of activities. Mercury concentration was observed to be less than g/m 3. VIMTA Labs Limited, Hyderabad 197

173 district, Tamilnadu Chapter 10 Summary and conclusion Ambient Noise Levels The noise monitoring has been conducted for determination of ambient noise levels at ten locations in the study area. The observations are given below: Day time Noise Levels (L day ) The day time noise levels were ranged in between 45.2 db (A) to 68.2 db (A). The maximum value 68.2 db (A) was recorded at was recorded at Melpakkam village (N2), and the minimum value 45.2 db (A) was recorded at Gumpuahintala village (N10). It is observed that the day time noise levels are in accordance to the prescribed limit of 55 db (A) for Residential areas. Night time Noise Levels (L night ) The night time noise levels were ranged in between 40.8 db (A) to 53.9 db (A). The maximum value 53.9 db (A) was recorded at Melpakkam village (N2), and the minimum value 40.8 db (A) was recorded at Gumpuahintala village (N10). It has been found that the night time noise levels are in accordance with prescribed limit of 45 db (A) for Residential areas Water Quality Six ground water samples and two surface water samples within the study area were considered for assessment. Surface Water Quality The analysis results indicate that the ph value at SW1 & SW2 was found to exist as 8.1 & 7.1 respectively, which is well within the specified standard of 6.5 to 8.5. The Total Dissolved Solids (TDS) concentration was found as 652 & 745. The chlorides were found as mg/l. The Sulphates were found as mg/l. Heavy metals in very low concentration and are well within the prescribed limits. It is evident from the above values that all the parameters are found to comply with the requirements of IS: (2012) "Specifications for Drinking Water." Ground Water Quality The analysis results indicate that the ph ranges in between 7.4 to 7.8, which is well within the specified standard of 6.5 to 8.5. The maximum ph of 7.8 was observed at GW3 and the minimum ph of 7.4 was observed at GW5. Total hardness was observed to be ranging from 190 to 350 mg/l. The maximum hardness (350 mg/l) was recorded at GW2 and the minimum (190 mg/l) was recorded at GW6. Chlorides were found to be in the range of mg/l, the maximum concentration of chlorides (53.2 mg/l) was observed at GW3 & GW6, and where as the minimum value (24.8 mg/l) was observed at GW1. Nitrates were found to be in the range of mg/l. The maximum value observed at GW3 (37.3 mg/l) whereas the minimum value observed at GW1 (3.9 mg/l). VIMTA Labs Limited, Hyderabad 198

174 district, Tamilnadu Chapter 10 Summary and conclusion The Total Dissolved Solids (TDS) concentrations were found to be ranging in between 223 to 414 mg/l, the maximum TDS observed at GW6 (414 mg/l) and minimum concentration of TDS observed at GW1 (223 mg/l). Potassium is found in between 1.3 to 8.5 mg/l. It is evident from the above values that all the parameters are found to comply with the requirements of IS: (2012) "Specifications for Drinking Water." Soil Quality A total of eight samples within 10 km radius of the plant site were collected for the assessment of soil quality. The sampling was carried out during study period. It has been observed that the ph of the soil in the study area ranged from 7.4 to 7.9 the maximum ph value of 7.9 was observed at S3, where as the minimum value of 7.4 was observed at S4 and S8. The ph of the soil is slightly alkaline to moderately alkaline. The electrical conductivity was observed to be in the range of 143 µmhos/cm to 210 µmhos/cm, with the maximum observed at S7 with the minimum observed at S4 respectively. The nitrogen values range between kg/ha. The nitrogen content in the study area falls in less to good category. The phosphorus values range between 61.6 to 94.4 kg/ha, indicating that the phosphorus content in the study area falls in average sufficient to more than sufficient category. The potassium values range between kg/ha. The potassium content in the study area falls in average to more than sufficient category Flora and Fauna As per MoEF and Forest Department of Tamilnadu state, it reveals that there are no Wildlife sanctuaries, National parks/biosphere reserves in 10 km radius from the proposed site boundary. As per the records of the Botanical Survey of India there are no plants of conservation importance in the study area. It can be concluded that there is one species belonging to Sch-I,2 species belongs to Sch-II and rest of species belongs Sch-III, Sch-IV and Sch-V of Wildlife Protection Act, Socio-Economic Environment As per 2001 census the study area consists of 2,78,458 persons inhabited in the study area of 10 km radial distance from the periphery of the proposed plant. The males and females constitute % and % of the study area population respectively. The average household size of the study area is 4.33 persons. In the study area, 21.45% of the population belongs to Scheduled Castes (SC). The study area experiences average literacy rate of 63.73%. As per 2001 census records, altogether the main workers works out to be 30.71% of the total population. The marginal workers and non-workers constitute to 8.19% and 61.11% of the total population respectively. VIMTA Labs Limited, Hyderabad 199

175 district, Tamilnadu Chapter 10 Summary and conclusion 10.4 Anticipated Environmental Impacts The environmental impacts during construction and operation phases of the project have been assessed and adequate management plan has been evolved to mitigate the impacts Impacts during Constructional Phase The environmental impacts during the erection stage will be short term, temporary in nature and will be confined very close to the project site. The manpower required for these activities should preferably be deployed from nearby villages. Land Environment There is no forest land or ecological sensitive land within proposed additional plant site. Hence, no major loss of agricultural productivity is envisaged. Impact on Soil The construction activities will result in loss of some vegetation cover, topsoil and earthen material to some extent in the plant area. However, it is proposed to use the soil and earthen material for greenbelt development and levelling of project site. Greenbelt will be developed in phased manner from construction stage onwards in the peripheral boundary of the additional project site. Apart from localized construction impacts at the plant site, no adverse impacts on soil in the surrounding area are anticipated. Impact on Air Quality The sources of emission during the construction period are from the movement of equipment at site and dust emitted during the levelling, grading, earthwork, foundation works. Exhaust emissions from vehicles and equipment deployed during the construction phase are also likely to result in marginal variation in the levels of SO 2, NO x, PM and CO. The impact will be for short duration and confined to the project boundary and the same is expected to be negligible outside the plant boundaries. The impact will, however, be reversible, marginal and temporary in nature. Proper maintenance of vehicles and construction equipment will help in controlling the gaseous emissions. Water sprinkling on roads and construction site will prevent the fugitive dust. Impact on Terrestrial Ecology The initial construction works at the project site involves land clearance. Greenbelt will be developed phase wise during construction to improve the aesthetic value in the area and to screen out the fugitive dust generated during construction. VIMTA Labs Limited, Hyderabad 200

176 district, Tamilnadu Chapter 10 Summary and conclusion The removal of vegetation from the soil and loosening of the topsoil generally causes soil erosion. However, such impacts will be confined to the project site and will be minimized through paving and water sprinkling. There are no existing matured wooded and useful trees in the site. However, greenbelt will be developed surrounding the plant facilities. Thus, no major adverse impacts are envisaged on terrestrial ecology. Socio-Economic Impacts Services of skilled and unskilled workers of different trades are required in large numbers. The project will provide either direct or indirect job opportunities to the local population as far as possible. These earnings are likely to change the economic status of local people Impacts during Operational Phase Impact on Soil Most of the impacts of power plant project on soils are restricted to the construction phase, which will get stabilized during operational phase. The impact on the topsoil will be confined to the proposed main plant area as all the activities are limited in the project site boundary only. Impact on Air Environment The impact on air quality is assessed based on emissions of the plant. Particulate Matter (PM), Sulphur dioxide (SO 2 ) and Oxides of Nitrogen (NO x ) will be the important pollutants emitting from the power plant. The maximum resultant ground level concentrations of PM, SO 2 and NOx are given in Table TABLE-10.4 RESULTANT CONCENTRATIONS DUE TO INCREMENTAL GLCs Pollutant Concentration ( g/m 3 ) Baseline Incremental Resultant Standards PM SO NOx A perusal of previous sub-section reveal that the maximum incremental short-term 24 hourly ground level concentrations for PM, SO 2 and NOx likely to be encountered in the operation of the power project are 1.39, and g/m 3 respectively occurring at a distance of about 2.0 km in the East direction. Impact on Water Environment ARS has already received uptake letter for 800 m 3 /day water from existing borewell vide letter no (192)/CGWA/SECR/ dt. 16 March VIMTA Labs Limited, Hyderabad 201

177 district, Tamilnadu Chapter 10 Summary and conclusion Garland drains around the ash dyke will be provided for the collection of run-off water during monsoon season. The wastewater generated, will be treated and mixed in guard pond and finally utilised for ash handling system and green belt development. The guard pond will be suitably lined to prevent percolation into ground. The ash pond will be provided with HDPE lining to prevent any kind of percolation into ground. Therefore the impact on surface and ground water will be insignificant. Impact of Solid Waste Generation Imported coal (100%) will be used in the existing & the proposed power project. The details of the solid waste generation are given in Table TABLE EXPECTED SOLID WASTE FROM POWER PLANT Sr. No. Plant Quantity of Generation Mode of Disposal 1 Ash* Fly ash Bottom ash MTPA MTPA MTPA Emphasis will be given for supply to potential users in dry from. Remaining ash will be disposed into HDPE lined ash dyke through HCSD method 2 Used Oil 2000 KLPA Will be supplied to authorized recyclers 3 Sewage sludge 2.4 TPA Sent to sludge drying beds and used as manure 4 Domestic solid waste / municipal solid waste 5.25 TPA Organic portion will be dried, composted and used as manure. Inorganic portion will be handed to authorised recyclers Major portion of the ash will be utilized by supplying to potential users. Efforts will be made to utilize 100% fly ash as per the Fly Ash Notification, 1999 and as amended later. It is proposed to collect fly ash from ESP hoppers in dry form and provide/supply to potential ash users depending on the demand. The balance unutilized ash will be disposed off using High Concentrated Slurry Disposal (HCSD) technology. Impact on Aquatic Ecology The impacts on aquatic ecology due to project would be negligible as the treated effluents from the power project will meet the prescribed standards prior to final discharge. Similarly, as the discharge water will not have much higher temperature than the receiving body, no thermal effects on receiving body due to discharge are envisaged. Hence, the impacts on ecology of the region will be insignificant. VIMTA Labs Limited, Hyderabad 202

178 district, Tamilnadu Chapter 10 Summary and conclusion Impact on Reserve/Protected Forest The incremental gaseous concentrations and noise generated during operation of the power plant are not likely to cause any adverse impact on ecology of forest bocks within the study area. Impacts of Noise Levels The noise generating sources are pumps, compressors and boilers. The predicted noise levels will be ranging in between 32 to 36 db(a) and the same will recede further as the distance increases. Hence, the impact of the noise levels on the surroundings will be insignificant. Impact on Human Health The impact from the air emissions is not expected to be significant since the stack design and the atmospheric conditions are such that the ambient air quality at present as well as in future after the proposed facility will be within the prescribed ambient air quality limits set forth by CPCB. Impact on Public Health and Safety The discharge of waste materials (stack emission, wastewater and solid wastes) from process operations may have potential impact on public safety and health. The wastewater generated from power plant will be treated before discharging outside. It is proposed to reuse the wastewater to the maximum extent. Since, the adverse impacts on ambient air and soil quality are predicted to be low it is anticipated that with effective implementation of control measures suggested for pollution control, the impact on public health will be minimum Environment Management Plan Environment Management Plan during Construction Phase Air Quality Management The activities like site development, grading and vehicular traffic contribute to increase in PM and NO x concentrations. The mitigation measures recommended to minimize the impacts are: Water sprinkling in construction area; Asphalting the main approach road; Proper maintenance of vehicles and construction equipment; and Tree plantation in the area earmarked for greenbelt development. VIMTA Labs Limited, Hyderabad 203

179 district, Tamilnadu Chapter 10 Summary and conclusion Water Quality Management The mitigation measures recommended to minimize the impacts are sedimentation tank to retain the solids from run-off water; oil and grease trap at equipment maintenance centre; Septic tanks to treat sanitary waste at labour camp; and utilizing the wastewater in greenbelt development. The wastewater from labour colony will contribute to higher BOD concentrations. The mitigation measures recommended to minimize the impacts are: Sedimentation tank to retain the solids from run-off water; Oil and grease trap at equipment maintenance centre; Packaged STP/Septic tanks to treat sanitary waste at labour colony; and Utilizing the wastewater in greenbelt development. Noise Level Management Operation of construction equipment and vehicular traffic contribute to the increased noise level. Recommended mitigation measures are: Good maintenance of vehicles and construction equipment; Restriction of construction activities to day time only; Plantation of trees around the plant boundary to attenuate the noise; and Provision of earplugs and earmuffs to workers. Ecological Management During construction, vegetation in the plant premises is required to be cleared. The measures required to be undertaken to minimise the impact on the ecology are: The felling of trees will be kept at minimum; and The greenbelt having vegetation density of 2500 trees/ha will be developed. Social community Management Constructional activities will generate employment to local and near by villages. For construction work force, temporary sanitation facilities (septic tanks and soak pits) will be set-up for disposal of sanitary sewage. Similarly, rest rooms and canteen facilities will be provided for truck drivers during construction as well as operation phase of power plant. VIMTA Labs Limited, Hyderabad 204

180 district, Tamilnadu Chapter 10 Summary and conclusion Environment Management Plan during Operation Phase Air Pollution Management Fugitive and stack emissions from the power plant will contribute to increase in concentrations of PM, SO 2, and NOx pollutants. The mitigative measures recommended in the plant are: Installation of ESP of efficiency more than 99.99% to limit the PM concentrations below 50 mg/nm 3 ; Provision of stack of adequate height (Existing m & Proposed 220 m) for wider dispersion of gaseous emissions; Provision of water sprinkling system at raw material storage yard; Asphalting of the roads within the plant area; Provision of dust extraction systems at dust generating source. Developing of Greenbelt around the plant to arrest the fugitive emissions; Online flue gas monitors as well as flue gas flow rates and temperature measurement shall be provided for all stacks; and Usage of washed/beneficiated coal may be explored. Water Pollution Management Wastewater will be generated from boilers in the power plant. Besides, domestic wastewater from canteen and employees wash area will also be generated. Adequate treatment of wastewater in ETP prior to recycle/reuse to maximum extent will be done. Provision of separate storm water system to collect and store run-off water during rainy season and utilization of the same in the process to reduce the fresh water requirement will be made. Suitable rainwater harvesting structures will be constructed. Noise Pollution Management Equipments will be designed to conform to noise levels prescribed by regulatory authorities. Provision of thick greenbelt shall attenuate the noise levels. Solid Waste Management Solid waste in the form of ash will be generated in a coal based thermal power plant. The total ash generated in the plant will be MTPA out of which 80% will be fly ash i.e MTPA and balance will be bottom ash of MTPA. The following measures shall be taken for solid waste management: In general, ash will be given to potential ash users; The excess ash will be disposed off using high concentrated slurry disposal system to HDPE lined ash pond; The generated waste oil shall be explored to be used in boiler furnace with HFO or shall be given to authorized recyclers; The organic portion of solid waste generated in the Sewage Treatment Plant (STP) will be used as manure in greenbelt development; and Maintaining the data base on solid waste generation such as quantity, quality, treatment/management. VIMTA Labs Limited, Hyderabad 205

181 district, Tamilnadu Chapter 10 Summary and conclusion Ash Utilization Fly ash will be utilized in brick plants, cement industries, as micro-nutrient in fertilizer, road construction and backfilling of mines. The fly ash will be utilized in various construction materials to the maximum extent and 100% utilization will be achieved as per the new fly ash notification. Greenbelt Development Additional greenbelt will be developed around the plant site. The total greenbelt around the power plant complex will be about ha (35.96%) upon expansion. The greenbelt will be maintained with a density of minimum 2500 trees/ha inside the plant premises. A total cost of Rs. 5 Crores is proposed to be spent for the development of additional greenbelt. Cost Provision for Environmental Measures It is proposed to invest about Rs. 360 crores on pollution control, treatment and monitoring systems for proposed power plant with a recurring cost of Rs. 26 crores per annum 10.6 Post Project Environment Monitoring Programme Post project environmental monitoring is important in terms of evaluating the performance of pollution control equipments installed in the project. The sampling and analysis of the environmental attributes will be as per the guidelines of CPCB/SPCB. The frequency of air, noise, surface water and ground water sampling and location of sampling will be as per the directives of Tamil Nadu Pollution Control Board Risk Assessment and Disaster Management Plan The hazard potential of oil and estimation of consequences in case of their accidental release during storage, transportation and handling has been identified and risk assessment has been carried out to quantify the extent of damage and suggest recommendations for safety improvement for the proposed facilities. Risk mitigation measures based on MCA analysis and engineering judgments are incorporated in order to improve overall system safety and mitigate the effects of major accidents. An effective Disaster Management Plan (DMP) to mitigate the risks involved has been prepared. This plan defines the responsibilities and resources available to respond to the different types of emergencies envisaged. Training exercises will be held to ensure that all personnel are familiar with their responsibilities and that communication links are functioning effectively. VIMTA Labs Limited, Hyderabad 206

182 10.8 Project Benefits Rapid Environmental Impact Assessment for the proposed augmentation & district, Tamilnadu Chapter 10 Summary and conclusion The proposed 545 MW thermal power plant will result in improvement of infrastructure as well as upliftment of social structure in the surrounding villages. The people residing in the nearby areas will be benefited indirectly. The major benefit due to the proposed project will be in the sphere of generating temporary employment for substantial number of personnel. During the erection phase about 50 people on an average will be employed. The manpower for the proposed expansion of power plant during operational period is estimated to be about 200 persons in addition to the existing manpower. Implementation of the power project will result in the following benefits 10.9 Conclusion Employment will be provided to eligible persons both during construction and operational phase Temporary employment for people from the neighboring villages during construction phase. Community development activities such as training of local unemployed youth in various construction skills, English speaking, personality development, development of self help groups for women, providing drinking water facility, strengthening of rural roads, deepening of ponds etc., State will get revenue from payment towards taxes and water cess etc., Providing dispensary with a medicine bank to cater to the health care needs of the surrounding villages. Providing vocational training to women in areas for their self employment. Utilizing the services of ex-servicemen for providing training to youth in areas of personality development, security etc., The proposed expansion of the power plant has certain level of marginal impacts on the local environment. However, development of this project has certain beneficial impact/effects in terms of bridging the electrical power demand and supply gap and providing employment opportunities that will be created during the course of its setting up and as well as during the operational phase of the entire project. VIMTA Labs Limited, Hyderabad 207

183 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant 11.0 DISCLOSURE OF CONSULTANT 11.1 Introduction VIMTA Labs Limited is a leading multi-disciplinary testing and research laboratory in India. VIMTA provides contract research and testing services in the areas of clinical research, pre-clinical (animal) studies, clinical reference lab services, environmental assessments and analytical testing of a wide variety of products. VIMTA - Environment Division has been in the forefront of its vision to provide better environment through guiding and assisting the industry for sustainable development. A stalwart in the mission to protect and preserve the natural resources on earth for future generations, Vimta offers extensive research and consultancy services in the field of Environment. With its rich experience, multidisciplinary expertise and with the support of its state-of the-art analytical equipment, the services offered by Vimta are wide ranging and encompasses entire gamut of Environment Management and Monitoring Services. With its emphasis on quality services, Vimta, over the years, has evolved itself into a single reference point in India for Comprehensive Environmental Services The Quality Policy VIMTA is committed to good professional practices and quality of operations in its testing, validation and research services. VIMTA shall ensure customer satisfaction by maintaining independence, impartiality and integrity in its operations. VIMTA shall provide the services in accordance with national and international norms. VIMTA shall implement quality system as per ISO/IEC and applicable GLPs & GCPs, to generate technically valid results/data. VIMTA shall ensure that all its personnel familiarize with the policies and procedures of the quality system and implement the same in their work Milestones and Accreditations Registered with an initial investment of Rs.2 Lakhs Recognized by ISI (now known as Bureau of Indian Standards) Qualified by the criteria of Ministry of Environment and Forests was notified as one of the 14 standard Environmental Laboratories published in the Gazettee of India Licensed for carrying out tests on Drugs and Pharmaceuticals Cherlapally land purchased with plans of larger, more comprehensive facility Accredited by NCTCF, DST, Government of India (the forerunner of NABL) Laboratories shifted to new facility at Cherlapally State-of-the-art equipment worth Rs.60 million procured Accredited by NABL under its revised scheme, certified by Standards Australia, Quality Assurance Services as per ISO/IEC Guide 25 and ISO Vimta Labs Limited, Hyderabad / Coimbatore 209

184 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant GLP Compliance Restructuring of Vimta from 165 to 100 associates with same performance Accreditation by GOSSTANDART and joint venture for certification of Food Exports with ROSTEST, Russia World Bank Recognition ANVISA Brazil certification USFDA accepts Vimta Bioequivalence study report. Showcased Vimta at AAPS (USA) and ICSE-CPHI (Germany) Vimta VHS Research Center inaugurated at Chennai, Launched district laboratories at Visakhapatnam and Vijayawada, Patient service centers launched at 160 locations across the country Vimta Labs Recognized by Saudi Arabian Standards Organization Vimta increases people strength from 225 in 2003 to 400 in Vimta achieves export turnover of $ 2.5 million Vimta releases its first fortnightly medical newsletter Vaidyalekha, Vimta enters Gulf market - bags a contract for Environmental Consultancy in Kuwait Vimta acquires 10.7 acres of land in S.P.Biotech Park Genome Valley, Hyderabad, to create a world class Research Laboratory of sq.ft by July Vimta starts a new state of the art speciality services in Molecular Diagnostics at TICEL Bio-Tech Park at Chennai Vimta expands its overseas activities. Undertakes environmental assignments in Saudi Arabia and Tanzania 2008 Vimta has been Pre-Qualified by World Health Organization (WHO) Undertaken Comprehensive Environmental Impact Assessment in Cameroon, Africa 2010 Accredited by QCI/NABET, Government of India for EIA report preparation Undertaking environmental and social impact assessment study in Tanzania, Africa as per IFC-World Bank Guidelines 11.4 Management and Board of Directors 1. Dr. S.P. Vasireddi Chairman and Managing Director 2. Mrs. Harita Vasireddi Director Projects 3. Mr.V. Harriman Director Technical 4. Mr. V.V. Prasad Executive Director 5. Mr. S. Subrahmanyam Director 6. Mr. T.S. Ajai Director 7. Dr. Pavuluri Subba Rao Director 8. Prof. D. Balasubramanian Director Vimta Labs Limited, Hyderabad / Coimbatore 210

185 11.5 Services Offered Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Spread over the 70,000 Sq.ft lush green garden premises at Cherlapally, Hyderabad (India), the scientifically designed and meticulously groomed infrastructural facility of the Central Laboratory of VIMTA has the most sophisticated instruments backed by an excellent team of professionals. The 40,000 Sq.ft, three-storied, 120 roomed, centrally air conditioned state-of-the-art Laboratory equipped with Rs.100 million worth analytical instruments and computerized data management systems, all under one roof is perhaps the only one of its kind in South Asia in the contract testing and research sector. Vimta offers various services under the following divisions: Environment; Analytical; Clinical Reference Lab; and Clinical Research. The environment division of VIMTA Labs Limited (Vimta) has its presence all over India including a strong association with international consultants like Japan Bank for International Cooperation (JBIC), Kennametal Inc. - USA, BBL - UK, Rudal Blanchard UK, E&E Solutions Japan, NEPESCO & KNPC Kuwait, Marafiq Saudi Arabia and others. Vimta has the following credentials: 11.6 Services Recognitions by BIS; Recognitions by Ministry of Environment and Forests, Govt. of India; Recognitions by State Pollution Control Boards (wherever applicable) ; Recognitions by Department of Science & Technology, Govt. of India (NABL) ; Recognitions by Ministry of Defense, Govt. of India; Recognitions by APEDA, Ministry of Commerce, Govt. of India; Recognitions by Saudi Arabia Standard Organization (SASO), Saudi Arabia; Recognitions from NEMC, Tanzania; Accreditations by NCTCF; Certification from Standard Australia; Recognition from ANVISA Brazil; Quality Assurance Services as per ISO/IEC 17025; and Quality Assurance Services as per ICH Guidelines Environment essentially being a multi-disciplinary science, the range of services offered by the Division are also comprehensive and caters to the needs of industry, pollution control agencies, regulatory authorities and in a larger pursuit of a green globe. The services under Environmental Assessments include: Site Selection and Liability Studies; Environmental Impact Assessments; Environment Management Plans; Carrying Capacity based Regional Studies; Environmental Audits; Solid and Hazardous Waste Management; Vimta Labs Limited, Hyderabad / Coimbatore 211

186 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Risk Assessment (MCA,HAZON,HAZOP) & DMP; Occupational Health and Safety, Industrial Hygiene; Environmental Monitoring for Air, Meteorology, Water, Soil, Noise, Ecology and Socio-Economic; Industrial Emission Source Monitoring; Offshore Sampling and Analysis of Marine Water and Sediments; Marine Ecological Studies; Marine Impact Assessment; Rehabilitation and Resettlement Studies; Forestry and Ecological Studies; Geological and Hydro-geological Studies; Land Use /Land Cover Studies based on Remote Sensing; Socio-Economic Studies; Due Diligence Studies; Epidemiological Studies; Wasteland Management Studies; and Study on Bio-indicators. The services under Environmental Chemistry include: Analysis of Water, Wastewater, Soil, Solid Waste, Hazardous waste as per Indian and International Codes; Source Emissions and Work Zone Air/Noise quality monitoring; Analysis of SVOCs, VOCs, PAH, BTEX, AOX, PCB s, TCLP metals, TOC etc.; Categorization of Hazardous Waste; and Pesticide Residue Analysis Facilities Vimta-Environment Division is located in scientifically designed Central Laboratory with the state-of the-art modern facilities to offer vide range of services in indoor and outdoor monitoring and analytical characterization in the field of Environment. Further, it is ably supported by highly skilled and experienced team of professionals in the fields of Science, Engineering, Ecology, Meteorology, Social Planning, Geo & Hydro-geology, and Environmental Planning. Besides the regular monitoring equipment such as Respirable Dust Samplers, Automatic Weather Monitoring Stations, Stack Monitoring Kits, Personal Samplers, Noise Meters, Portable Water Kits etc, the other major specialized equipment include: Monostatic Sodar Designed by National Physical Laboratory, GOI; Integrated Noise Level Meter Quest, U.S.A; Flue Gas Analyzers Testo, Germany; 113-A Gravimetric Dust Sampler-Casella, London; ICP AES Varian, USA; Gas Liquid Chromatographs with FID, ECD & pfpd Varian, USA; Gas Chromatograph with Mass Detector Varian, USA; Atomic Absorption Spectrometer [AAS] Varian, USA; PAS-AFC-123 instrument; Vimta Labs Limited, Hyderabad / Coimbatore 212

187 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant High Performance Liquid Chromatograph; Laser Particle Size Analyzer; Monostatic Sodar Designed by National Physical Laboratory, GOI; Integrated Noise Level Meter Quest, U.S.A; Flue Gas Analyzers Testo, Germany; 113-A Gravimetric Dust Sampler-Casella, London; ICP AES Varian, USA; Gas Liquid Chromatographs with FID, ECD & pfpd Varian, USA; Gas Chromatograph with Mass Detector Varian, USA; Atomic Absorption Spectrometer [AAS] Varian, USA; 11.8 Quality Systems The fact that Environment division and its supporting Site Laboratories are accredited by NABL (IS ) and Ministry of Environment and Forests and by other international bodies such as Asian Development Bank (ADB) and World Bank stands testimony to its emphasis on Quality Systems Achievements Being the first laboratory to be recognized under Environment Protection (EP) Act by GOI in 1986, Environment Division with its best mind power and industrial knowledge competency that allows it to compare with the best in the business. The Environment Division till date has executed about 350 Environmental Impact Assessment (EIA) and Environment Management Studies with Risk Assessment and Disaster Management Plans and obtained statutory approvals. Supported by the strong modern laboratory support and experienced hands, Environment division is well equipped in conducting Due Diligence, Phase-I and Phase-II studies. Undertaken specialized studies such as Regional Environmental Impact Assessment on Carrying Capacity Principle; Upper Air Meteorological studies using SODAR for major Industrial Complexes. Associated with prestigious studies such as Environmental Pollution monitoring around Taj Trapezium, Pre and Post Satellite launch studies for SHAR, ISRO and monitoring for offshore Oil & Gas exploration for deep-sea water and sediment sampling. The services offered include vide spectrum of industries covering Power, Chemical, Cement, Mining, Steel & Alloys, Metallurgical, Dye & Intermediates, Bulk Drugs, Pesticides, Agro-Chemicals, Petro-Chemicals, Refineries, Pulp & Paper, Oil & Gas Exploration & Production, Asbestos, Infrastructure, River valley, Foundries etc. The Environment division has also offered its services to major infrastructure projects such as Ports, Oil & Gas Pipelines, Green field Air Ports, Roads and Highways. Vimta Labs Limited, Hyderabad / Coimbatore 213

188 expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant DETAILS OF PERSONNEL INVOLVED IN CURRENT EIA REPORT Sr. No. Name Qualification Position Contribution Experience 1 Mr. M. Janardhan M.Tech (Env) Head & Vice President(Env) Co-ordination About 20 years of experience in the field of air quality impacts, and noise, environmental management and environmental engineering 2 Mr. K.S. Muneeswaran M.E. (Env. Engg) PGDES, PGDIS Senior Manager Co-ordination About 22 years of experience in the field of environmental chemistry and environmental impact assessment 3 Mr. G.V. Raghava Rao M.Tech (Env) Dy. Manager Expert About 11 years of experience in the field of Environmental Impact Assessment studies 4 Mr. P.Niranjan Babu B.Com Asst Manager Secretarial About 21 years of experience in the field of Environmental Monitoring and secretarial assistance 5 Ms. Durga Bhavani M.Sc. (Env. Sci) Group leader Expert About 8 years of experience in the field of environmental impact assessment 6 Dr. Subba Reddy M.Sc., Ph.D Scientist Expert About 6 years of experience in the field of Environmental Impact Assessment studies 7 Mr. S. Kishore Kumar M.Tech (Env) Env Engineer Expert About 3 years of experience in the field of Environmental Impact Assessment studies 8 Mr. S. Rajeswaran M.E., (Env. Engg) Env. Engineer Expert About 3 years of experience in the field of environmental monitoring and environmental impact assessment 9 Mr. J. Bharatvaj M.E., (Env. Engg) Env. Engineer Expert About 1 year of experience in the field of environmental monitoring and environmental impact assessment 10 Mr. ACH Ramesh Kumar M.Sc (Env) Scientist Expert About 10 years of experience in the field of Environmental Impact Assessment studies 11 Mr. T. Seshagiri Rao M.Sc (Env) Scientist Expert About 8 years of experience in the field of Environmental Impact Assessment studies 12 Dr. Subba Reddy M.Sc., Ph.D Scientist Expert About 6 years of experience in the field of Environmental Impact Assessment studies 13 Mr. G. Krishnamoorthy M.Sc., (Env. Sci) Scientist Expert About 3 years of experience in the field of Environmental Science and monitoring 14 Mr. C. Yathavaraj M.Sc., (Env. Sci) Scientist Expert About 2 years of experience in the field of Environmental Science and monitoring 15 Mr. A. Ashok B.Tech (Biotechnology) Jr. Env. Engineer Expert About 1 year of experience in the field of Environmental Science and monitoring 16 Mr. T.Karthikeyan B.Tech (Biotechnology) Jr. Env. Engineer Expert About 1 year of experience in the field of Environmental Science and monitoring 17 Mr. P. Krishna I.T.I (Civil) Sr. Draftsman Cartography About 12 years experience in the field of Environmental and Civil Drawings 18 Mr. J. Ramakrishna I.T.I (Civil) Sr. Draftsman Cartography About 11 years experience in the field of Environmental and Civil Drawings Vimta Labs Limited, Hyderabad/Coimbatore 214

189 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 215

190 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 216

191 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 217

192 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 218

193 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 219

194 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 220

195 Rapid Environmental Impact Assessment for the proposed augmentation & expansion of existing thermal power plant at Gummidipoondi, Thiruvallur District, Tamilnadu Chapter 11 Disclosure of consultant Vimta Labs Limited, Hyderabad/Coimbatore 221