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

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

Manywells Landfill:determination, management &

communication

Ann BarkerLead Officer Contaminated Land

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

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

Manywells: location

1994: A new waste disposal landfill site is born, formed from a disused sandstone quarry in Cullingworth

Photo-montage by local resident

Commissioned and operated as a licensed waste disposal site 1994 to 2001

Photo-montage by local resident

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

Manywells became an “orphan” site

Site overfilled by approx 90,000 cubic metres

Uncontained leachate seeping to surface

The first view…Waste mass towers over surrounding land levels

Unstable gradients

Landfill gas migration onto public bridleway and into woods

Exposed waste seen from bridle path

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

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

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. 2001 – identified inspection priorities…

Inspection Strategy: Site Specific Priority Factors

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

Leachate migration

Groundwater: Potential migration pathway via compromised landfill liner

Cross Section

Waste deposits

Main clay liner

Leachate detection layer

Leachate saturated waste deposits

Leac

hate

det

ectio

n ch

ambe

rLeachate ingress to LDC

Rough Rock Flags (Bedrock & Minor Aquifer)

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

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

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

Conceptual Site Model: a starting point

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

Den Making in woodland

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

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

Determination Document: Page 1

Determination Document: SLP1

Determination Document: SPL2

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.”

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

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.”

Determination Document: Map

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

Part IIA: Post determination issues

• Neighbouring land owners

• Power generation company

• Escrow fund - E.A. High Court action

• Negotiations with Crown

• Site ownership issues

Resources: SCA / SCE(R) / CLCP2002/2003 Intrusive Investigation - landfill gas/leachate £15,000

2003-2004 Remediation – landfill gas/leachate, interim SPL management

£128,000

2004-2005 Urgent works to comply with H&S. Consultancy on remedial options

£144,000

2005-2006 Remediation – gas/leachate, interim SPL management

£188,000

2006/2007 Remediation – gas/leachate. Interim SPL management etc.

£637,000

2007/2008 Remediation – MWH on project team. Solution developed. Temp cap & large boreholes

£465,000

2008/2009 Remediation – Modelling and final design works, access road planning application

£381,000

2009/2010 &

2010/2011

Bid - not including ‘ineligible costs’. £2,000,000

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

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?

Technical Challenge 2:

Control required for:

• Leachate• Landfill Gas• Stability

RISK

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

2006 WORK

Leachate Containment – drains, manholes, pumping

Landfill Gas – flare, pipe network

Site Investigation– 6 boreholes along spine of tip

Security and SafetyAssessment, Signing, Fencing and Control

Landfill Closure

Landfill Processes

Processes at Manywells

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

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

Interim Works 2007/08

• AIM – induce settlement through

– Control of leachate

– Generation of landfill gas

• Site works October 07 – May 08

• Value £594k

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

What we achieved 2008- Pumped Leachate Volumes

Monthly average

April 2007 to March 2008 258m3

April 2008 to Dec 2008 470m3

December 2008 431m3

January 09 (some frozen time) 420m3

June 09 275m3

Waste Mass Temperature

Borehole locations

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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

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

Community Confidence in L.A.

2002 2003 2004 2005 2006 2007 2008

Community meetings

with consultants

MCWG set up

LO

W

Year

HIG

H

2009

Communications activity• Communications with ward councillors• Members bulletin items• Neighbourhood Forum meetings• Community Newsletters since July 2006• Webpages – www.bradford.gov.uk/manywells • Manywells Community Working Group- 5

meetings since Oct. 07• Communications Strategy- April 2008

Community Working Groupsite visit

Community Newsletter

Posters

Communications Strategy

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

Brownfield Briefing Award: Best communcations/stakeholder engagement

Brownfield Briefing Award:Manywells Community Working Group

Manywells & Part IIA

TO CONCLUDE…!

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

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!

Every site needs ‘hands-on’ management

Thank

you

for

listening

ann.barker@bradford.gov.uk