APRIL 2011 The Avenue

Transcription

1 APRIL 2011 The Avenue 1

2 2 Location Plan

3 History Site Uses Past and Present Hunloke and Avenue Collieries Iron and Lime Works Coking Plant and Chemical Works Avenue Operational Operational Produced 18M Tonnes of Sunbrite Employed 800 staff 98 hectare site Licensed Waste Facility The Avenue - Operational Undoubtedly one of the finest in the world Gas Journal

4 Gas Purification Plant Gas Holders Chemical Plant Coal supply and blending Power Generation Coking Ovens Waste Disposal Area 4 Site Layout - Schematic

5 The Avenue The Problem Holder Role Site transferred to English Partnerships in December 1996 Objective to bring the site back into productive use Site transferred to emda April 1999 Funding from EP s National Coalfield Programme Main Issues Health and safety liabilities Environmental liabilities Hazardous derelict chemical plant Gross contamination The site drivers were statutory requirements not economic regeneration 5

6 emda s Strategy How to Tackle the Site Problem or Opportunity? Direct development by emda Transparency required due to site history Sustainable solution Promote best practice Stakeholder involvement Maximising outcomes Economic regeneration Public amenity Habitat creation Flood defence Technology demonstration 6

7 Lagoons Waste Tip Plant Area CPL The Avenue in Undoubtedly one of the finest in the world?

8 Identifying the Challenge 500 Boreholes 1000 Trial pits xxx Samples 350,000 of chemical tests Site Characterisation 8

9 Site Specific Risk Assessment and Modelling Contaminants of Concern Organics PAH S Phenols DRO s PRO s BTEX Cyanide Thiocyanate Ammonia Benzene Waste Tip Metals Arsenic Nickel Cadmium Chromium Mercury 9

10 A Off Site SW Plant Area DIAGRAMMATIC CONCEPTUAL MODEL High Level Stocking Area Direct Contact: Inhalation / ingestion Waste Tip inc. Lagoon 2 Wind blown particulates from exposed soils & during disturbance - onto third party land and general public River Rother and Flood Plain A NE Legend Source Pathway Metal Contamination Organic Contamination Inorganic Contamination Leachables Human Health Structures / Services Water Table Aggressive attack on services / foundations Vapours Lagoon 2 River Rother Made Ground Alluvium Coal Measures A Coal Measures Leaching of contaminants migration into controlled waters t. A Groundwater Flow SCALE Y. TEMPL DATE APPROVED JTS 10

11 The Criteria Controlled water contamination issues to address Improving river standard Protecting shallow ground water Human Health issues to address Site to be suitable for full public access Sports Pitches Residential development with gardens (800 houses) Other Issues Ecology Flood defence Adjacent residential areas 11

12 Key Areas to Address The Key Areas of concern Controlled Waters pollution Human health risks Sewers/drains/sumps on the site Waste Tip 6 key areas to address Order of priority - River Rother - Lagoon 2 -Waste Tip - Lagoon 4 - Sewers/drains/sumps on the site - Clean cover to contaminated areas Lagoon 2 River Rother Lagoon 4 12

13 Risk Assessment Initial generic assessment of quantities following characterisation - 2,700,000 m3 Site specific risk assessment revised quantity to 600,000m3 78% reduction in remedial effort Only possible with team work and partnership working with regulators 13

14 How to Treat the Material? Remediation Trials Needed to find how to treat the material to prove alternative to landfill Lagoon slurry a major problem - 40 trials carried out - 29 trials reported - EURODEMO Technologies trialed were 1. Bioremediation 2. Thermal desorption 3. Soil stabilisation 4. Soils washing 14

15 Making the Site Safe Dismantling, Drain-down and Demolition No record of decommissioning Substantial (but unknown) chemical residues Asbestos Dangerous structures 500 tanks 5000 pipe runs 15

16 Partnership Working - The Next Step Bringing a Delivery Expert Into the Team Complex project nature required early contractor involvement Bespoke Early Contractor Involvement (ECI) contract Preferred contractor appointed May 2006 VSD Avenue JV DEC Volker Stevin Sita Remediation 16

17 The Criteria Controlled waters criteria 4 areas (Consim Model) Within 100m of river Within 100m to 200m of river Away from river Development Area Within 200m of river Human health criteria 2 areas (CLEA model) Within 1m of surface Below 1m from surface Total of 6 re-use criteria Away from river Public open space Development Area 17

18 Working in Partnership to Deliver Sustainable Solutions Derivation of Remediation Options Avenue remediation options derived by partnership working. Technologies used focus on contamination removal but minimum treatment Remediation technologies to be used Selective excavation Complex sorting Soil washing Bio-remediation Thermal desorption 18

19 Appointed Contractor Appointed Contractor VSD Avenue on 09/09/09 19

20 Marcus Foweather Joint Venture Project Director 20

21 Project Overview The final project includes - 2,200,000m3 of earthworks - 250,000 m3 of complex sorting - 50,000 m3 of soil washing - 75,000m3 of bioremediation - 300,000 m3 of thermal desorption - 250,000 m3 of soil manufacture Construction of a substantial water treatment plant Relocation of 6,000 newts, 50 snakes, 250 watervoles In order to clean up the River Rother and shallow groundwater and allow the construction of - 28 hectares of development land - 5 hectares of sports pitches - 70 hectares of nature reserve 21

22 22 SITE CHALLENGES

23 23 Hydrocarbon on the river

24 24 Free product within cofferdam excavation

25 25 Possible thiocyanate within cofferdam excavation

26 26 Example of below BoE sump

27 27 General earthworks and backfilling with Suitable for re-use materials

28 Building a Cofferdam in Contaminated Ground 28

29 29 Cofferdam/Lagoon 2 Overview

30 30 Cofferdam excavation

31 31 Confined spaces escape sets chemical resistant boots or they melt!

32 32 REMEDIATION TECHNOLOGIES

33 Remediation - Complex Sorting 25 screen oversize to Ballistic separator separated waste streams Clean to site Thermal Bio 25mm down 50,000m3 soil wash Flotation tank for wood, plastics etc Clean material to site sludge to thermal/bio Used on Waste Tip Area 250,000 m3 Recyclables removed off site Asbestos removal separation at excavation face hand sorting on conveyor belt Magnetic belt 75mm finger screen oversize to crusher and site 33

34 34 Excavation of the Waste Tip

35 35 Waste Tip Sorting

36 36 Waste Tip Processing

37 37 Picking station

38 38 Discard bins

39 39 Output stockpiles

40 40 Timber stockpile from tip

41 Remediation - Bioremediation Lagoons Waste Tip River Used on low contamination lagoon and waste tip material 75,000m3 Natural process using insitu bugs in the organic material. Material processed in windrows. 41

42 42 Bio-Remediation

43 Remediation - Thermal Desorption Used on high contamination lagoon and waste tip material - 300,000m3 Destroys all organic contaminants Highly variable material to be treated Material blended to give consistent feedstock Moisture content - Calorific Value Plant capable of treating 25 t/hr of blended feedstock Plant to run 24 hours per day 7 days per week for 85% of the year 43

44 24/7 Operation of Thermal Treatment Plant By Day 44

45 24/7 Operation of Thermal Treatment Plant By Night 45

46 46 Off-gas ducting to feed carbon filters

47 47 Excavation of Lagoon 4 sediments

48 48 Loading into haulage trucks

49 49 Delivery to mixing area

50 50 Discharge into Storage pit

51 51 Mixing Pit Filled With Lagoon 4 Sludges

52 52 Loading into the plant

53 53 Well Cooked - Treated Material

54 54 Water Treatment Plant (inc. Bioreactor)

55 Site Ecology The project is over 100 hectares of derelict Land that has been left for many years and become home to many animals, reptiles and birds Project Objective to minimise short term impact by mitigation and maximise long term benefits by design. To do this we; employ environmental consultants are working in partnership with Derbyshire Wildlife Trust are liaising with Natural England 55

56 Site Ecology Creation of the nature reserve Habitats include wetlands grassland woodland meadow Establishment and funding for the nature reserve of a long term management system Translocation Trapping and moving of over newts and 50 grass snakes to new local habitats created by emda Moving the water voles from the River Rother corridor 56

57 The Site The Exit Strategy - 28 hectares of mixed use development - a flood alleviation scheme - 5 hectares of sports pitches - 65 hectares of nature reserve - Flood Risk Alleviation Dam Emda Require an Exit Strategy All non-development areas to be passed to LT with an in-perpetuity dowry Dam to pass to Environment Agency Delivery Partner - Derbyshire Wildlife Trust LT - Managing residual liabilities DWT managing the Site surface - Developing and maintaining the nature reserve - Using the work to train people with job skills, - Carrying out environmental education with local schools and groups 57

58 Working in Partnership with all Working with others to find a mutually acceptable solution Partnership working is the project ethos. This has lead to a partnership solution to the challenges on the site Involving the community in the process by Community liaison groups Consultation events Information Centre Newsletters Website For more information log onto or contact - foweather.marcus@decukltd.com 58