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Manywells Landfill: determination, management & communication Ann Barker Lead Officer Contaminated Land.

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Presentation on theme: "Manywells Landfill: determination, management & communication Ann Barker Lead Officer Contaminated Land."— Presentation transcript:

1 Manywells Landfill: determination, management & communication Ann Barker Lead Officer Contaminated Land

2 Structure of presentation Part IIA reminder Location and background Initial negotiations Assessment actions Determination Part IIA issues post-determination Resources Interaction with E.A. Technical challenges Leachate, temperature and gas Community confidence and communications Conclusion and recommendations

3 Part IIA: Reminder Backstop! Only to be used where other regimes are not applicable Requires viable potential or actual significant pollutant linkage Based on risk assessment Forensics - the polluter pays – search for appropriate persons

4 Manywells: location

5 1994: A new waste disposal landfill site is born, formed from a disused sandstone quarry in Cullingworth Photo-montage by local resident

6 Commissioned and operated as a licensed waste disposal site 1994 to 2001 Photo-montage by local resident

7 Site operator, Wastepoint Ltd, went bankrupt in 2001, deserting the site

8 Manywells became an “orphan” site

9 Site overfilled by approx 90,000 cubic metres Uncontained leachate seeping to surface

10 The first view… Waste mass towers over surrounding land levels Unstable gradients Landfill gas migration onto public bridleway and into woods

11 Exposed waste seen from bridle path

12 Background Operational waste management issues –Odour –Flies January 2002 –Contact from Minerals & Waste planners & E.A. –Site leachate not controlled –Multi-Agency meeting –Joint site visit –Huge public concern, political pressure to resolve January 2003 –Site determination

13 Initial negotiations : Legal situation January 2002 NOTE: Early days in Part IIA implementation! Site owner/operator bankrupt – therefore does not legally exist Property inc. waste management licence held by liquidators Then disclaimed as ‘onerous property’ under Insolvency Act Ownership of site reverted to Crown Escrow fund (for restoration) tied to licence (E.A./site owner) Planning – nothing to be achieved by enforcement – query re. Crown liabilities Power generation company on site

14 Initial negotiations: Implications January 2002 Waste Management legislation not applicable Part IIA action recommended by E.A. re. controlled waters – potential Special site? BUT - “Inspection Strategy for Contaminated Land in the Bradford District” Dec – identified inspection priorities…

15 Inspection Strategy: Site Specific Priority Factors

16 Initial Negotiations: 2002 Legal Counsel’s opinion – non-determination defensible where no significant pollutant linkage identified But if E.A. stopped pumping leachate then SPL could occur…? Therefore Assessment actions continued

17 Leachate migration

18 Groundwater: Potential migration pathway via compromised landfill liner Cross Section Waste deposits Main clay liner Leachate detection layer Leachate saturated waste deposits Leachate detection chamber Leachate ingress to LDC Rough Rock Flags (Bedrock & Minor Aquifer)

19 Site review: Controlled Waters Source/Contaminants –Leachate breakout on edges of site with run-off over surface across industrial estate –Groundwater – leachate migration potential via compromised main liner Potential pollutant linkages & receptors: –Surface water – via drainage systems via sewerage to Manywells Beck –Groundwater – E.A. Landsim modelling

20 Controlled Waters: significance? Surface water – leachate from breakout diluted on site and during run-off – no significant pollutant linkage Groundwater – potential pathway due to percolation of leachate via thin basal clay liner – potential significant pollutant linkage Note – NO proven significant pollutant linkages

21 Assessment Actions Conceptual site model (CSM) drafted in- house –No proven significant pollutant linkages identified –No risk to human health identified Determination based on controlled waters resisted

22 Conceptual Site Model: a starting point

23 Assessment Actions: Landfill Gas BUT concern about landfill gas identified IMC consultants - commissioned to review and report on potential risks from landfill and mine gases Potential threat to human health – potential gas migration through fractures in the rocks into –Woodland areas used for informal play by children (including dens) –Hollows in field where livestock shelter in poor weather conditions

24 Den Making in woodland

25 Part IIA & Manywells – key points Other regimes? –Waste management regime – failed –Planning regime – failed Viable significant pollutant linkages? –Surface water - pathway to Manywells Beck – not ‘significant’ due to leachate dilution before leaving site –Groundwater - pathway – potentially ‘significant’ over time –Landfill gas – potentially ‘significant’ low likelihood but extreme impact on human health possible in certain conditions

26 Determination process Note: Not many examples of determination documents available in 2002 Collation of evidence to confirm SPL Basic Risk Assessment Map/plan Format/Layout = Determination document

27 Determination Document: Page 1

28 Determination Document: SLP1

29 Determination Document: SPL2

30 Determination Document: Gas risk assessment “Therefore the Council has concluded that the proven presence of landfill gas in the ground surrounding the site, the identification of potential pathways and the presence of identified receptors are sufficient to conclude that there is a significant possibility of significant harm being caused.”

31 Gas concentrations Methane up to: –58%v/v in borehole outside site boundary –14% v/v in dry-stone wall adjacent to boundary –8%v/v in pinholes in hollows in field Carbon dioxide up to: –42%v/v borehole outside site boundary –24%v/v in dry-stone wall adjacent to boundary –30%v/v in pinholes in hollows in field

32 Determination Document: Groundwater Risk Assessment “Therefore the Council has concluded that: –the proven presence of landfill leachate in the leachate detection layer below the basal liner, –the modelled permeability of the secondary liner which may provide a pathway to groundwater, and, –the presence of groundwater beneath the site and of a licenced abstraction point, Manywells Spring, are sufficient to conclude that this land is in such a condition by reason of substances, in, on or under the land that pollution of controlled waters is likely to be caused.”

33 Determination Document: Map

34 Part IIA: Post determination issues Initial remediation solution – removal of 98K tonnes material from site – practical issues ‘Project management’ – with PCO/EHO & EHM (not key area of expertise) E.A. still involved in site pumping leachate therefore division of responsibilities

35 Part IIA: Post determination issues Neighbouring land owners Power generation company Escrow fund - E.A. High Court action Negotiations with Crown Site ownership issues

36 Resources: SCA / SCE(R) / CLCP 2002/2003Intrusive Investigation - landfill gas/leachate£15, Remediation – landfill gas/leachate, interim SPL management £128, Urgent works to comply with H&S. Consultancy on remedial options £144, Remediation – gas/leachate, interim SPL management £188, /2007Remediation – gas/leachate. Interim SPL management etc. £637, /2008Remediation – MWH on project team. Solution developed. Temp cap & large boreholes £465, /2009Remediation – Modelling and final design works, access road planning application £381, /2010 & 2010/2011 Bid - not including ‘ineligible costs’.£2,000,000

37 Interaction with E.A. Waste management licence – disclaimed Local E.A. waste management and Part IIA officers involved in discussions from start Special site status investigated National Capital Programme assessor involved from early in project Ongoing contact and meetings with assessors

38 The Technical Challenge 1: original option Proposal:- Remove 90,000 m3 of material = 22,000 Wagon movements Issues:- Sustainability Environmental Considerations Cost Short term fix solution? RISK and Where would it go?

39 Technical Challenge 2: Control required for: Leachate Landfill Gas Stability RISK

40 Technical Challenge 3: what were real problems? Significant Pollutant Linkages (SPLs) What? Where? Why? SAFE site. HSE Involvement REQUIRED CLEARER DEFINITION OF THE PROBLEM TO INFORM THE SOLUTION

41 2006 WORK Leachate Containment – drains, manholes, pumping Landfill Gas – flare, pipe network Site Investigation – 6 boreholes along spine of tip Security and Safety Assessment, Signing, Fencing and Control

42 Landfill Closure

43 Landfill Processes

44 Processes at Manywells

45 Project team and project development Early 2007 project team expanded Office of Government Commerce (OGC) Environmental Advice and Services shortlist Expression of Interest Supplier Day Tender and Tender Evaluation Quality and Price Appointment of MWH Partnering – establishment of 6 working groups

46 Manywells Landfill Remediation Project Our aim is… ‘To deliver a safe and sustainable solution with an acceptable landform to a timescale which is minimally disruptive to local communities’. … by using good project management and effective communications

47 Interim Works 2007/08 AIM – induce settlement through –Control of leachate –Generation of landfill gas Site works October 07 – May 08 Value £594k

48 Interim Works 2007/08 Site investigation - locate liner and leachate leaks Temporary clay cap - reduce water ingress Vertical drains - promote drainage of waste mass and improve gas production. Improve collection and control of landfill gas Formalise leachate drainage Increased Defra funding allowed some reshaping and deep drainage trenches

49

50

51 What we achieved Pumped Leachate Volumes Monthly average April 2007 to March m 3 April 2008 to Dec m 3 December m 3 January 09 (some frozen time) 420 m 3 June m 3

52

53 Waste Mass Temperature

54 Borehole locations BH10 BH13

55 BH

56 BH

57 Gas concentrations Boreholes outside site –Some reduction in gas concentrations due to rebalancing of gas field, new flare etc –Further improvement expected when new infrastructure installed and more gas drawn away from perimeter Boreholes on site –Increase in gas concentrations and volumes as waste dries out and methano-genesis restarts –New flare requires energy input to ensure operation –Still monitoring effects of site works –Long term gas production unknown –Power generation potential under review but power generation infrastructure may not be viable

58 The Plan Key Works Redistribution of the waste mass to provide stable slopes and an acceptable landform Tying the existing liner to a new clay cap Infrastructure – Leachate ‘dirty’ water under cap + pumping Infrastructure – Gas wells, heads, pipework and flare Infrastructure – ‘Clean’ water system above cap Soils and planting. Key to success of remediation and the restoration of the site

59

60 Community Confidence in L.A Community meetings with consultants MCWG set up LOW Year HIGH 2009

61 Communications activity Communications with ward councillors Members bulletin items Neighbourhood Forum meetings Community Newsletters since July 2006 Webpages – Manywells Community Working Group- 5 meetings since Oct. 07 Communications Strategy- April 2008

62 Community Working Group site visit

63 Community Newsletter

64 Posters

65 Communications Strategy

66 Part IIA: Communications Summary Establish good communications early – it takes some time but saves a lot more in the long run Get key contacts in community involved Tell the community what is going on even when nothing seems to be happening on the site Note – significant resource implications if done right – not eligible costs for CLCP

67 Brownfield Briefing Award: Best communcations/stakeholder engagement

68 Brownfield Briefing Award: Manywells Community Working Group

69 Manywells & Part IIA TO CONCLUDE…!

70 Part IIA: Landfill Site Determination Recommendations: –Part IIA is a last resort – do not go there unless you have no options! –Ensure you get good legal advice –Check Land Registry - ensure defensible boundary line around the determined area –If orphan site Separate regulatory role from project manager role Project management skills are essential

71 Site remediation: practical points Flexibility Circumstances change, There is more than one right answer, Control and manage expectations of rapid action Bring in additional expertise where necessary Funding issues – not just CLCP Risk associated with regulatory action Landfill sites are organic beings – no two are the same!

72 Every site needs ‘hands-on’ management

73 Thank you for listening


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