The New PPC Regime And Its Impact On Quarry Landfills
A detailed look at how the new Pollution Prevention Control Regulations will affect quarry operators planning to landfill worked-out areas or sites
The Pollution Prevention Control Regulations present new challenges for quarry operators wishing to landfill worked-out areas or sites. SLR Consulting director John Leeson and his team have prepared and submitted over 50 PPC applications for landfill operators (both major and independent). In this article he examines the new regime and how it will affect those operators who have yet to apply for PPC permits.
The landfilling of waste has, since 1994, been regulated by the Waste Management Licensing Regulations (WMLR). These regulations replaced the former Control of Pollution Act (COPA) regime under which holders of waste-disposal licences could hand back their licences at any stage in the development of a landfill.
The WMLR were brought in under the umbrella of the Environmental Protection Act 1990 in order to comply with parts of the Waste Framework Directive issued by the then European Economic Community (now the EU).
The WMLR introduced a step change into the regulation of landfill sites. In particular, licence holders had to accept that landfills could be a long-term liability as much as a short-term asset. Issues such as technical competence for landfill managers and the need for the protection of groundwater, by the lining of sites, became routine parts of landfill management.
A typical application for a waste-management licence would include a set of completed application forms, a working plan which described how the site would be developed and operated, and a groundwater (or Regulation 15) risk assessment to show how the landfill could be operated without polluting groundwater.
Details of the technical competence of the manager, previous convictions of the operator and proposals for a financial provision — which would often extend for a period of at least 30 years following the closure of the landfill — would also have to be supplied.
The PPC Regulations
The Pollution Prevention and Control (PPC) Regulations came into force in 2000 and represent the most significant change to the regulatory regime for landfills since the WMLR were introduced in 1994. Landfilling is one of a series of activities, such as the manufacture of cement and lime, or ceramic products, listed in the new regulations.
The regulations prohibit the operation of a listed installation without a PPC permit after a prescribed date. For existing installations they set out, for each industry sector, a series of relevant periods within which duly made applications for permits have to be submitted. The end of each period is the prescribed date for that sector unless a duly made application has been submitted in which case the prescribed date is the date of determination of the application.
The regulations originally stated that the prescribed dates for the landfill sector were 1 January to 31 March 2007. However, the implementation of the Landfill Directive via the Landfill Regulations 2002 led the Govern-ment to decide that landfills needed to enter the PPC regime more rapidly. There are now seven prescribed periods, from June 2003 to May 2006, for groups (or tranches) of landfills, in which PPC applications have to be made if they are to continue operating.
The Landfill Regulations required operators to submit a Conditioning Plan in 2002, to describe how the site would comply with the Landfill Directive. On the basis of the information contained in these plans, the Environment Agency in England and Wales and SEPA in Scotland (the Agency) allocated each landfill to an appropriate tranche, generally on the basis of risk.
The allocation process took account of the engineering of the landfill, its groundwater setting and the type of the waste that the landfill operator proposed to accept.
One of the most important aspects of the Landfill Regulations is the requirement for landfills to accept only:
- hazardous waste or
- non-hazardous waste (including inert waste) or
- inert waste.
However, four rounds of applications (tranches 1, 2a, 2b and 3) have already been made — representing over 300 landfills.
PPC v WMLR — HOW DO THEY DIFFER?
The PPC Regulations introduce a series of new requirements upon the operator including the need for PPC applications to:
- include a site report (which describes the condition of land prior to development) as a benchmark against which applications to surrender the permit can be considered
- consider accidents and their consequences
- demonstrate that resources such as energy and raw materials will be used carefully
- prevent the unnecessary waste of materials
- use Best Available Techniques (BAT) to achieve these objectives and provide a high level of protection for the environment.
PPC applications
In order to carry on operating an existing landfill, its operator must submit a ‘duly made’ PPC application before the end of the relevant period. If this is not received in time the landfill cannot operate until a subsequent application is determined.
A duly made application should contain:
- a completed set of PPC application forms (part A, B and F)
- the correct application fee
- an expenditure plan
- drawings and information describing the environmental setting and design of the landfill
- risk assessments which examine:
—landfill gas
—stability
—nuisance and health
—habitats (in certain circumstances). (see box 2)
The complexity of the application process is illustrated by the need to use a 114-page landfill sector application form. It requires details of the management procedures that the applicant will follow and of any environmental-management system that the applicant may have in place. It is understood that a somewhat simplified form is being prepared for inert landfills.
Because numerous factors, such as stability and landfill gas risk assessments, and the impact on groundwater of historic waste deposits, have to be considered, the re-permitting process often involves redesigning a landfill site.
Accordingly, to ensure that the application is duly made, it is recommended that at least six months is allocated for gathering monitoring data and for consultation with the Agency at pre-application meetings.
The application process
Once it has been accepted as being duly made, the Agency has four months in which to determine the application. It is placed on a public register and also sent to consultees such as the Food Standards Agency, the relevant planning authority, the Primary Care Trust and nature conservation agencies, such as English Nature. This period may be extended by mutual agreement or if the Agency decides that further information is required in order to be able to make the determination.
In practice, SLR are finding that applications are taking a minimum of eight months to determine and there are several applications submitted in June 2003 which are yet to be determined. While the application is being processed the site’s Waste Management Licence stays in force.
SLR understand that several applications have already been refused because applicants have not demonstrated that they can comply with the Landfill or Groundwater Regulations. In such circumstances the applicant has the right of appeal and during the appeal period can continue to operate under the existing Waste Management Licence.
ISSUES RELEVANT TO QUARRY RESTORATION
The impact of the PPC and Landfill Regulations on quarry restoration schemes is already being felt. Several previously consented restoration schemes have now been called into question as a result of detailed work being undertaken for PPC applications.
Currently, the effects are being experienced in relation to landfills for non-hazardous waste, as most of the landfills accepting inert waste have yet to pass into the PPC regime.
Old waste deposits
Landfills for non-hazardous waste have to include a geological barrier, an artificial sealing liner (such as a geomembrane) and a leachate drainage layer. While this requirement is often standard practice in recent filling areas, there are many large landfills where initial cells constructed in the 1980s do not have such containment engineering.
If the areas are adjoining current and future tipping areas, these also have to be included as part of the PPC installation and, therefore, have to be compliant with the Groundwater Regulations and, in some circumstances, the Landfill Regulations. Agency guidance5 recognizes that it is not practicable to re-engineer landfill containment systems where waste has already been deposited, but it notes that permit applications may be refused if the applicant cannot identify measures to render discharges to groundwater from these areas acceptable within the first four years of the life of a permit.
One solution that operators have taken is to define the installation boundary to exclude the existing waste deposits, but this approach appears to be contrary to current Agency guidance5, which suggests that three-dimensional (or so called piggy-back) installation boundaries are not acceptable.
Wherever possible, the preferred approach should be to include all parts of the landfill within the installation boundary. In some circumstances it has been possible to do so by improving the cap on the old parts of the site to limit leakage so that the improved site will comply with the Groundwater Regulations.
However, this approach is only possible in certain circumstances and the fate of quarry restoration schemes relying on landfills where older engineering may now be substandard is still in the balance.
Geological barriers
An allied issue brought into focus by PPC applications is the need to have a low-permeability geological barrier between the waste mass and groundwater. At some sites, such as clay pits, a natural geological barrier is available. However, at many hard-rock quarries the fractured rock is water-bearing even if it is classified as a non-aquifer.
In such circumstances, the original practice of applying plastic geomembranes to vertical quarry faces is now no longer acceptable and instead operators have to install an artificial geological barrier, such as compacted clay, between the face and the waste.
Stability risk assessments show that the use of clay lining systems against quarry faces may be prone to problems as the waste in the landfill settles, leading to failures in the lining system. Accordingly, landfill designers have had to identify innovative solutions to allow landfilling to continue in deep hard rock quarries.
Inert landfills
As box 1 shows, the need for a geological barrier is universal to all landfills. However, guidance1 on hydrogeological risk assessment suggests that, for truly inert wastes, nominal (ie not low permeability) barriers may be appropriate.
To date, the Agency has adopted a cautious response to this approach and has asked applicants to consider the impact of ‘rogue loads’ of non-inert waste being accepted.
In some circumstances the Agency has suggested that the Landfill Regulations requirements for a low-permeability geological barrier should be applied to inert landfills, which may render many sites uneconomical.
HOW WILL OPERATORS BE AFFECTED?
Landfill operators will inevitably be affected by the introduction of the PPC regime to regulate landfilling, not least because of the cost of preparing the complex applications and the application fees, which — for large landfills — have been in excess of £20,000 alone.
The changes described may appear to be far-reaching but at many well-run sites the standards required are already adopted. However, at sites where there is not an up-to-date working plan or design, the transition into the PPC regime may be difficult.
The requirements for monitoring arising out of the Landfill and PPC Regulations are more extensive than has often been the case and could include monitoring of noise, dust and air quality in addition to the more routine monitoring of groundwater, surface water and leachate.
SLR are aware of some independent operators who have decided to close their landfills in advance of the deadline for PPC applications in light of the increase in management and operational costs that this regime will involve.
SUMMARY
The changes affecting landfill sites are part of a wide-ranging review of the way in which waste is managed throughout the European Union. Although many of the landfill sites in the UK already comply with the requirements of the Landfill Directive, there are many sites where compliance will be difficult or impossible.
The early closure of landfill sites, as a result of these changes, could have significant effects on the ways in which quarries are being restored and, in some cases, could lead to operators having to make planning applications to amend approved restoration schemes.
Accordingly, the future of many quarry restoration schemes, which have been closely linked with the success of landfill projects, could be called into question and early review of each scheme, in the context of the requirements of the Landfill and PPC Regulations, is recommended in order that quarry and landfill operators can plan for the changes ahead.
REFERENCES
Some of the references can be found on the Environment Agency website: www.environment-agency.gov.uk. For Scotland visit: www.sepa.org.uk and for Northern Ireland visit: www.ehsni.gov.uk
- Hydrogeological Risk Assessments for Landfills and the Derivation of Groundwater Control and Trigger Levels, March 2003.
- Guidance on Monitoring of Landfill Leachate, Groundwater & Surface Water, August 2003.
- Environment Agency, GasSim User manual, 2002.
- Environment Agency R&D Technical Reports P1-385/ TR1 and TR2, 'Stability of Landfill Lining Systems', February 2003.
- Landfill Directive Regulatory Guidance Note Interpretation of the Engineering Requirements of Annex 1 of the Landfill Directive, November 2003.
See also: Integrated Pollution Prevention and Control, A Practical Guide, Edition 3, February 2004, on the Defra website: www.defra.gov.uk.
To contact John Leeson, director at SLR Consulting, tel: (01527) 597000 or email: jleeson@slrconsulting.co.uk