There are generally three types of guidance on noise levels that can be consulted for noise and vibration assessments:

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1 7B.1 Introduction This annex provides details of the basis for development of criteria for evaluating the significance of noise and vibration impacts for the Simandou Project and describes the methods used for predicting impacts from the Simandou Railway: Section 7B.2 reviews sources of international guidance relating to noise and vibration; Section 7B.3 explains the approach to prediction and evaluation of construction noise; Section 7B.4 explains the approach to assessing noise from railway operations; and Section 7B.5 explains the approach to assessing noise and vibration impacts from blasting during tunnel construction. 7B.2 International Guidance There are generally three types of guidance on noise levels that can be consulted for noise and vibration assessments: levels which represent the on-set of noise or vibration impacts (which are often contained in planning guidance for new projects, but which do not require any mitigation of noise); mitigation trigger levels where the potential noise or vibration impacts are considered to be sufficiently high to require mitigation to be considered at source taking account of local conditions and the benefits of a scheme; and levels at which regulations require noise mitigation at the receiver in the form of noise insulation or mitigation at the affected buildings due to the levels being unacceptable without such mitigation. The World Health Organisation (WHO) together with the Organisation for Economic Co-ordination and Development (OECD) and the International Finance Corporation (IFC) are two of the main bodies that have collected data and developed their own assessments on the effects of the exposure to environmental noise. On the basis of these assessments, guideline values for different time periods and situations have been developed. 7B.2.1 WHO/OECD Guidance The World Health Organization (WHO 1999) Guidelines for Community Noise (Eds B. Berglund, T. Lindvall, D.H. Schwela. Geneva: WHO) provide the following generic guidance concerning the onset of health effects from noise. to protect the majority of people from being seriously annoyed during the daytime, the sound pressure level on balconies, terraces and outdoor living areas should not exceed 55 db LAeq for a steady, continuous noise; to protect the majority of people from being moderately annoyed during the daytime, the outdoor sound pressure level should not exceed 50 db LAeq; and at night, sound pressure levels at the outside façades of living spaces should not exceed 45 db LAeq and 60 db LAMax, so that people may sleep with bedroom windows open. These values have been obtained by assuming that the noise reduction from outside to inside with the window partly open is 15 db. 7B.2.2 IFC EHS Guidelines The IFC General EHS Guidelines differentiate between two principal receptor categories, residential and industrial, but are not specific to any particular source. The noise level guidelines for these receptors are summarised in Table 7B.1. They make reference to noise from facilities and stationary noise sources, and are commonly applied as design standards for industrial facilities. Whilst they offer general guidance on 7B-1

2 noise effects, the IFC has indicated that they are not directly applicable to transport or mobile noise sources. No specific guidance is provided on noise from railway sources. Measurements are to be taken at noise receptors located outside the project property boundary. Table 7B.1 IFC Noise Level Guidelines (General EHS Guidelines Table 1.7.1) Receptor Maximum Allowable Ambient Noise Levels, LAeq,1hr, dba Free field Daytime Night-time 07:00 22:00 22:00 07:00 Residential, institutional, educational Industrial, commercial IFC sectoral EHS Guidelines for Railways (IFC 2007) do not provide specific guidance on noise levels from railways. 7B.3 Construction Noise 7B.3.1 Introduction This section presents a review of current noise guidance materials to inform the development of construction noise impact assessment criteria for the Simandou Railway and describes the method used to predict construction noise. 7B.3.2 Review of Construction Noise Guidelines Construction sites have special characteristics compared with other major noise generators. Construction is generally undertaken in the open, is usually of a temporary duration, and varying levels of noise are produced by several different types of noise sources. Equipment can be stationary or mobile; stationary equipment operates in one place for one or more days at a time, and can have either fixed power operation (pumps, generators, compressors) or variable operation (pile drivers, pavement breakers), whereas mobile equipment will move around sites (bulldozers, mobile cranes, haul trucks etc). Noise levels created by construction equipment can vary greatly and depend on factors such as type of equipment, the specific model, the operation being performed, duration of the activity, and the condition of the equipment. There are no standardised criteria for assessing construction noise impacts, and consequently such criteria are usually determined on a project-specific basis. Criteria should take into account the existing noise environment, the absolute noise levels during construction activities, and the receptor land use. The current approaches taken to determining land use construction noise impact criteria in European Union (EU) countries including the UK, the USA, Australia, Japan, Korea and Hong Kong are all similar in that the noise sensitivity of various land uses is used to provide the primary indicator of an acceptable noise level attributable to construction activities for different times of the day (daytime, evening and night time). The other significant factor in assessing the effects of noise impacts is the duration of the impact. A review of construction noise level impact assessment criteria, expressed as LAeq values normalised to preferable (minimum) and acceptable (maximum) values for day and night time periods, from these countries, is presented in Figure 7B.1. The ranges presented in Figure 7B.1 cover daytime and night time criteria, as well as some instances of 24 hour criteria. 7B-2

3 Figure7B.1 Range of Residential Noise Limits for Construction (LAeq) 7B.3.3 Construction Noise Impact Criteria The basic rationale behind the proposed construction noise impact assessment criteria for the Simandou Project is one that will ensure the adequate protection of existing sensitive land uses whilst permitting the construction works to be completed in a practical manner. The guidance summarised above has been reviewed to establish a suitable set of criteria for the Simandou Project. These are presented in Table 7B.2. The grades of significance are as defined in Chapter 1: Introduction of the SEIA. The duration of construction noise is accounted for by applying variable noise thresholds for significant impacts. A threshold for critical noise impact is defined based on the level at which it is generally considered that hearing damage could start to occur (LAmax 85dBA). Table 7B.2 Evaluation Criteria for Construction Noise affecting Residential Receptors Operating Period Daytime Noise Level, db LAeq, 1hr Night time Noise Level, db LAeq, 1hr All Periods LAMax Significance Minor Moderate Major Minor Moderate Major Critical Short term exposure < 1 month Medium term exposure 1 to 6 months Long term exposure > 6 months < >75-80 >80 < >60-65 >65 < >70-75 >75 < >55-60 >60 < >60-65 >65 < >55 > 85 7B-3

4 7B.3.4 Method for Predicting Construction Noise Bruel & Kjaer s Predictor V8.01 noise modelling software has been used to calculate noise emissions from construction activities utilising the methods identified within British Standard, BS5228:2009 Noise and Vibration Control on Construction and Open Sites. BS5228 provides guidance concerning methods of predicting and measuring noise and identifies indicative noise level outputs, in terms of Sound Power Levels (SWL or Lw) and activity LAeq (the A-weighted equivalent noise level), for a wide range of construction plant. It also recommends methods of noise control for construction and open sites where work activities or operations generate significant noise levels. The computer model incorporates identifiable noise source data, surrounding terrain characteristics and the barrier effects of nearby buildings and structures. It can be used to calculate noise levels at specified locations (single point calculation) or noise level contours over a defined area (contour calculation). Due to the expanse of the project and number of receptors, the contour calculation feature was used to predict noise levels from the railway construction activities. Factors such as meteorological conditions (eg wind speed and direction), atmospheric absorption, and ground attenuation can influence the level of noise received from day to day. However, predicting these effects is complex and instead a conservative approach has been adopted by assuming still air and no atmospheric absorption, which potentially over-predicts noise levels. 7B.4 Railway Operation Noise Criteria 7B.4.1 Introduction This section reviews current noise guidance on operational noise from railways, details the evaluation criteria developed for railway operations and describes the prediction method. The guidance is generally derived from research into human response to noise or vibration and the criteria are developed taking into account the need to protect the wellbeing of the community and the opportunity for individuals to enjoy sleep, relaxation and conversation without unreasonable interference from intrusive noise. 7B.4.2 Review of Railway Operational Noise Criteria There is no specific international or national numerical guidance for operational railway noise. The IFC EHS Guidelines for Railways note that: railway noise is generated from a variety of sources, each contributing to the total noise output. Sources include rolling noise generated by the contact between wheel and rail during normal movement and braking; aerodynamic noise generated by the train pushing air (particularly for high speed trains); and traction noise generated by the engine and cooling fans. This guidance goes on to recommended noise reduction or prevention strategies, but does not give guidance in terms of railway noise. The IFC does, however, give guidance on noise from Toll Roads (IFC EHS Guidelines for Toll Roads 2011) which states as follows. World Bank Group Noise Guidance for Toll Roads, April 2011 Traffic noise can be a significant nuisance and may be loud enough to interfere with normal conversation (22) and can cause stress in children and raise blood pressure, heart rates, and levels of stress hormones (23). Traffic noise levels are reduced by distance, terrain, vegetation, and natural and manmade obstacles. Management practices to prevent, minimise, and control noise include: Consideration of noise impacts during road design to prevent adverse impacts at nearby properties through the placement of the road right-of-way and / or through the design and implementation of noise control measures discussed below (24) (25). 7B-4

5 Design and implementation of noise control measures may include the following: Construction of the road below the level of the surrounding land Noise barriers along the border of the right-of way (eg earthen mounds, walls, and vegetation) (26) Insulation of nearby building structures (typically consisting of window replacements) Use of road surfaces that generate less pavement / tire noise such as stone-matrix asphalt es to the Guidance: (22) At a distance of 50 ft, traffic noise ranges from about 70 dba for cars to 90 dba for heavy trucks. (23) Evans, Gary W. et al. (2001) (24) For example, the U.S. Federal Highway administration has established noise impact criteria, such as L10 (sound level exceeded 10 percent of the time) = 70 dba for residential land use. A new road project should not cause a significant increase in existing noise levels at nearby properties. (25) Traffic noise is generally not perceived as a nuisance for people who live more than 150 meters from heavily travelled highways or more than 30 to 60 meters from lightly travelled roads. (26) The most effective noise abatement measures include noise barriers and mounds, which can reduce noise by 5 dba or more. The cost of noise walls in the US has been estimated at $1.3 million per mile (NCHRP Project (04) The guidance on mitigation is also relevant to design and operation of railways, with the exception that reduction of the noise at the rail / wheel interface on a railway is normally addressed through maintaining the track in good condition. The guidance includes reference to one example of noise limits for roads from the USA (see note 24 above) which suggests a threshold for residential land of 70 dba. In the absence of international criteria, standards and guidance from other countries have been reviewed including the United Kingdom (UK), other European Union (EU) countries, the United States of America (USA), Australia, Japan, Korea and Hong Kong. Reference is also made to a review of noise regulations and guidance carried out by the International Institute of Noise Control Engineering (I-INCE) in 2009 (1). Railway noise level criteria for various countries are indicated in Figure 7B.2. All the values given are exterior noise levels at residential receptors, normalised to free field where possible to provide an equitable comparison. The ranges presented in Figure 7B.2 cover both daytime and night time criteria, as well as some instances of 24 hour criteria. Figure 7B.2 Residential Operational Noise Limits (LAeq) (1) Survey of Legislation, Regulations, and Guidelines for Control of Community Noise (I-INCE Publication 09-1), I-INCE, B-5

6 More detail from the INCE review are provided in Table 7B.3. The noise limits presented in Figure 7B.2 and Table 7B.3 are not completely comparable, as they differ in terms of: parameters: standards are set in terms of various parameters including LMax, LAeq, Lden, LA90 and Ldn and limits in these indices are not directly comparable; reference times: times defining day and night vary between regulatory regimes; rail bonus : in some cases a rail bonus of 5 db is taken into account to recognise the fact that people tend to be less sensitive to railway noise than other transport sources as rail noise is not usually continuous like industry and road traffic, and people tend to habituate more to rail noise. In some cases this correction is subtracted from the predicted noise level from the railway. 5 db has been added to the relevant standards so that the values in Table 7B.4 can be compared directly; and the difference between impact assessment thresholds and triggers for mitigation controls. The standards also vary depending on their purpose and the action that is required when they are exceeded. In general the lower levels are applied to planning for new housing and can be used to define the on-set of noise impact. For example, the UK level of 55 dba during the day applies to new housing where no mitigation would be required on either railway or houses. Higher levels are generally set as limits for acceptable noise from railways. These may require the provision of noise insulation (for example double glazing and forced ventilation) at the receptor if they are exceeded. It is assumed that conditions around the Simandou Railway are unlikely to be conducive to application of noise insulation. 7B-6

7 Table 7B.3 Summary of Review Findings from I-INCE Country Lday Leve Lnight Lden LAeq 24hr Ldn Rail Bonus included Austria Rail bonus has been included in LAeq limit Belgium Denmark 64 LAmax es Limits for new railways or for expanded operations on existing infrastructure Limit for hospital school or residential - limits for summer residential and camping are lower (59) Finland Existing Residential, new residential is 45 db at night. France Limits for new or modified land uses Germany Effective limit taking into account the fact that 5 db is subtracted from rail noise for new railways Italy Converted from façade level (subtract 2. 5 db and round up) The Netherlands Depends on land use (from "nature" to "industrial") Norway 58 Also includes max at night Portugal Takes into account 5 db reduction in limit for new railways Sweden No planning restriction at this level Switzerland Turkey UK Korea US For new sources, residential receptors and includes effect of minimum rail bonus No noise mitigation measures for new housing are required at this Higher limits of 66 Ld, 61 Ln would result in requirement for noise insulation Noise at this level is defined as an "impact", but 65 db is described as a "severe impact" vdf B-7

8 Draft planning policy in Western Australia regarding train noise (1) provides particularly useful guidance as it will be applied to mining rail projects. This sets out three levels for onset of noise impacts presented in Table 7B.4. Table 7B.4 Draft Statement of Planning Policy: Road and Rail Transport Noise: Western Australian Planning Commission Time Period Exposure Level 1 Noise Target Exposure Level 2 Exposure Level 3 Noise Limit Day Time 6.00am 10.00pm Night Time 10.00pm 6.00am 55 dba LAeq, 16hr 55 dba < LAeq, 16hr < 60 dba 60 dba LAeq, 16hr 50 dba LAeq, 8hr 50 dba < LAeq, 16hr < 55 dba 55 dba LAeq, 8hr e: Noise Level is to be determined at a point 1 metre from the edge of the site or building façade that is the most exposed to the noise source, and at a height of 1.5m from the ground level at that point. Noise assessments should generally reflect the impact of any future growth in road and rail traffic, based on a 20 year forecast period. The 5 db differences between the outdoor noise target and the outdoor noise limit represent an acceptable margin for compliance. Normally, it is practicable to achieve outdoor noise levels within this acceptable margin where either receptors or railways exist. It is recognised that in some cases it may not be practicable to achieve the noise criteria. In these circumstances reference is made to considerations such as benefit, cost, feasibility, community preferences, amenity impacts, safety, security and conflict with other planning and transport policies. 7B.4.3 Evaluation Criteria for Operational Noise from the Simandou Railway The standards and guidance reviewed above were used to define the criteria for evaluating the significance of railway noise set out in Table 7B.5. Table 7B.5 Evaluation Criteria for Operational Noise affecting Residential Receptors Operating Period Daytime LAeq dba Night time LAeq, dba LAmax Significance Minor Moderate Major Minor Moderate Major Critical Railway noise < >60-65 >65 < >55-60 >60 > 85 LAeq is used as the principal parameter for determining the significance of noise impacts except for critical impacts which are determined by an LAmax value. An LAmax criterion would be more appropriate for use for a railway that is used only by a few trains in a day, or where trains pass very close to receptors (typically within metres), particularly during the night time where sleep disturbance is a potential issue. As the nearest receptors on the Simandou Railway will be at least 60 m away (outside the construction corridor) and there is a constant service level throughout the daytime and night time, LAeq is considered to be a more appropriate parameter. 7B.4.4 Method for Predicting Operational Noise SoundPLAN noise modelling software was used to calculate noise emissions from the railway at receptor locations (settlements) identified along the route. The model takes into account the number of trains that pass a given point (up to one train in each direction per hour), the speed of trains, whether they are laden or unladen, and the number of freight wagons and locomotives. (1) Western Australian Planning Commission, 2009; Draft Statement of Planning Policy: Road and Rail Transportation Noise. 7B-8

9 The SoundPLAN Model implements the NORD (1996) (1) calculation method for the propagation of noise from railways. This methodology has the advantage that it enables prediction of LAeq and maximum (LAMax) noise levels. NORD (1996) uses standard railway source terms from a measured database, which are specified in terms of sound power per unit length of trains. The most appropriate source term was selected which represents a diesel hauled Norwegian freight train. The source terms are not provided separately for locomotives and wagons, but for typical freight train configurations it is normal for the wagons to dominate the noise levels from a train so that precise configurations are not expected to have a significant effect on predicted levels. To calibrate the predictions so that they reflect the type of train that would typically be used by Rio Tinto, noise levels were calculated and compared with measured values from a freight train at a Rio Tinto facility in Australia (2). The predicted level using NORD (1996) for the reference situation was found to be 4 db higher than measured at 750 m. On this basis it would be logical to subtract 4 db to calibrate the model, but comparison with a parallel calculation made using the UK method Calculation of Railway Noise (CRN) (3) indicates that a correction of 2 dba would provide a reasonable conservative estimate. The noise modelling is based on the indicative alignment illustrated in Chapter 2: Project Description. The ground is assumed to be flat either side of the railway which provides a reasonable worst case prediction: in areas where the railway will run in cutting the actual noise levels from the scheme will be lower as the cutting acts as an effective noise barrier. There will be a small increase in noise where the railway is elevated but the difference will typically be less than 2 db. The locations of settlements were established as point locations from aerial photography from The use of single points introduces some uncertainty but since most are small villages, the exact locations of properties are unlikely to introduce uncertainties that are sufficiently large to affect the overall conclusions. 7B.5 Blasting 7B.5.1 Introduction This section presents the review of current guidance materials relating to blasting emissions to inform the development of operational blasting impact assessment criteria for the Simandou Railway. Blasting from mining and construction activities can have impacts on surrounding people, wildlife and structures including plant, machinery, buildings and pipelines through airblast (air overpressure) and ground vibration. Whenever blasting is carried out, energy is transmitted through the air from the blast site in the form of airborne pressure waves. These pressure waves comprise energy over a wide range of frequencies. Some is higher than 20 Hz and perceptible as sound, but the majority is below 20 Hz and hence inaudible, but can be sensed as concussion. The combination of sound and concussion is known as airblast. Airblast can excite secondary vibrations at an audible frequency in buildings and it is usually this effect which has been found to result in comments from occupants. There is no known evidence of structural damage from excessive airblast levels. Energy is also transmitted through the ground as vibration. The effect of vibration on people is highly subjective, as one person may tolerate high levels that would be unacceptable to someone else. It is therefore difficult to offer advice on suitable levels of ground vibration because of the uncertainties in response. Appropriate limits need to take account of local conditions and the nature of the works. 7B.5.2 Review of Blasting Guidance In the absence of Guinean or international blasting guidelines the following sources were reviewed: (1) Railway Traffic Noise - Nordic Prediction Method. Tema Nord: 1996:524, Nordic Council of Ministers, (2) Cape Lambert Port B Development: Noise Assessment (Rpt Rev0-29 July 08), SVT, (3) Calculation of Railway Noise, HMSO, B-9

10 1. Ontario Limits for Quarries (Canada); 2. Office of Surface Mining Reclamation and Enforcement (OSMRE), USA; 3. Australian and New Zealand Environment and Conservation Council (ANZECC) Technical Basis for Guidelines to Minimise Annoyance due to Blasting Overpressure and Ground Vibration (ANZECC, 1990); 4. British Standard BS6472: 2008 Guide To Evaluation of Human Exposure to Vibration in Buildings Part 2: Blasting Induced Vibration; 5. British Standard BS5228 (2009) Code of Practice for noise and vibration control on construction and open sites; 6. Minerals Technical Advice e 2: Coal (MTAN), January 2009 (UK Wales); 7. Minerals Planning Guidance e 9 (MPG), 1992 (UK) and Scottish Government Circular 26/1992; and 8. Australian Standard AS Explosives Storage, Transport and Use. The guidelines are defined limits for airblast, measured in dbz or dblinear, and ground vibration, measured as Peak Particle Velocity (PPV) in mm/s. A summary is presented in Table 7B.6. Table 7B.6 Common Blasting Emissions Criteria Emission Type Receptor Airblast db(z) Residential 128 Peak Particle Velocity (mm/s) Recommended maximum ground vibration Offices, commercial & industrial buildings Residential Regional Criteria Ontario 1 USA 2 Australia UK 12.5 e: References are to the list of relevant blasting guidelines above. 129 (< 6Hz) 133 (< 2Hz) 134 (< 0. 1Hz) 31 ( < 100m) 25 (> 100m) 19 (> 1500m) 115 (95%) (max) 3 5 (95%) 3 10 (max) (95%) (max) 6 6 (95%) 6 6 (95%) 7 12 (max) 7 25 (95%) (95%) (max) 5 2 (long term) (day) 4 5 (max) 3 2 (night) 4 Criteria for avoidance of structural damage from transient vibration from blasting are provided in Australian Standard AS Explosives - Storage, Transport and Use (ANZECC 2006), British Standards BS 6472: 2008 and BS7385: 1993 and German standard DIN : These are summarised in Table 7B.7. Thresholds for structural damage are generally above those specified in Table 7B.6. Table 7B.7 Common Ground Vibration Limits for Structures Type of Structure Ground Vibration Criterion (mm/s) Source Power Transmission lines (overhead) Buried Pipework (steel) 100 Roads 20 Site Buildings / Offices / Workshops AS 2187,2 (ANZECC 2006) DIN : Table 2 Line 1 Conservative criteria 2 x ANZECC Guidelines DIN : (Table 1 Line 1) Conveyors 100 Terrock Consulting (2008) [1] (standard construction) e: [1] An investigation into the effects of blasting on the conveyors at Cumnock Colliery (NSW, Australia) undertaken by Terrock Consulting Engineers found that a peak particle velocity (PPV) of 100 mm/s would not cause overloading of the conveyor structure with the conveyor belt running (Terrock Consulting Engineers, July 2008). 7B-10

11 7B.5.3 Evaluation Criteria for Blasting The guidance summarised above was used to establish criteria for evaluating the significance of emissions from blasting for the Simandou Project. These are set out in Table 7B.8. The criteria are designed to ensure adequate protection of sensitive land uses whilst permitting the operations to be conducted in a practical manner. The criteria are presented as 95 percentile limits for human comfort in occupied buildings and avoiding risk of cosmetic and structural damage to buildings from long term effects of vibration. Lower limits are set for the night time period. No distinction is made between minor and moderate significance because of the nature of impacts resulting from blasting and the response of receptors. Critical impacts from airblast are identified where airblast noise from blasting exceeds 140 dbz, generally accepted as the safe threshold for hearing. Table 7B.8 Criteria for Evaluation of Impacts from Blasting Period Airblast db(z) 95 percentile Minor / Moderate Major Critical Vibration PPV mm/s 95 percentile Minor / Moderate Daytime <115 > > > 140 <2 >2-5 > 5-10 > 10 Night time <105 > > > 140 <1 >1-2 >2-5 > 5 Major Critical 7B.5.4 Ground Vibration and Airblast Prediction Methodology Ground vibration and airblast levels have been predicted using the methodology outlined in the ICI Blasting Guide (ICI 1995) to provide an understanding of the potential of impacts from blasting. 7B Airblast Prediction The 95th percentile airblast site law, which may be exceeded up to 5% of the total annual blasts is defined by the peak airblast level (SPL) measured in db (Z) and is defined as: Airblast OP (95%) = log 10 (SD) where scaled distance is calculated as MIC is the maximum explosive charge mass (kilograms) detonated per delay at any 8 millisecond interval; and d is the distance between the charge (blast location) and receptor. 7B Blasting Vibration Prediction The Peak Vector Sum (PVS) ground vibration site law is defined as: PVS (mm/s) = 1140 (SD) -1.6 where scaled distance is calculated as MIC is the maximum explosive charge mass (kilograms) detonated per delay at any 8 millisecond interval; and d is the distance between charge and receptor. 7B-11