Landfills
Landfilling in the European Community in Accordance with the Landfill Directive
Derek Greedy
Landfilling within the European Union (EU) when it was formed varied quite considerably from member state to member state so one of the key drivers was to have uniformity of landfill operations. Landfill was considered to be a dirty word in northern Europe as a result of the need to produce energy rather than dispose of waste. Landfills were few and far between with disposal of municipal waste to energy recovery facilities. For the UK and much of southern Europe, energy was not so much the driver, but instead the disposal of waste. However, it was clear was that the standards in these countries varied considerably with some operating “state-of-the-art landfills” and others merely dumping waste as you now see in developing economies.
European Landfill Directive
As a result, the Council Directive 99/31/EC on the landfilling of waste set out to impose minimum technical standards and it did not stop member states from imposing tighter ones. However, for the majority of Member States where landfilling was the prime disposal route for its waste, the directive was transposed into national legislation virtually unchanged.
The Landfill Directive places the onus on the Member State to ensure that there is compliance; any enforcement action would be against the Member State rather than the individual operator within that Member State. For example, when using the biodegradable municipal waste diversion targets, each Member State would make a return to the EU to confirm progress. If the diversion targets are achieved within the timeframe specified, it would not matter to the EU whether one operator or one local authority had not achieved the target—what matters is the overall number (seeMunicipal Biodegradable Waste Diversion Targets sidebar). Failure to achieve the diversion targets would result in infraction proceedings against the Member State. It would be up to to the Member State to take sanctions against any individual operator or local authority if it had failed to comply with the transposed legislation.
There are specific landfill permit procedures as described in Articles 8 and 9 of the Directive that have to be adopted. Applications for permits must be accompanied by a number of risk assessments—including groundwater risk, landfill gas and stability—which demonstrate the efficacy of the engineering design. The application also has to be accompanied by an environmental statement discussing clearly how the applicant will mitigate against the potential of environmental harm from the landfill’s day-to-day operations, including litter, dust and noise.
There is also a specific requirement to reduce the production of methane gas from landfills.
It calls for a technical adaptation committee to create uniform waste acceptance procedures. The operator is required to demonstrate how he will make financial provisions throughout the entire lifetime of the landfill—from construction to operations and finally through the aftercare period.
Directive Requirements
The Landfill Directive requires each Member State to have procedures in place to prevent or reduce negative landfill effects on the environment, in particular the pollution of surface water, groundwater, soil and air, and the greenhouse effect (more commonly referred to as climate change). Technical standards need to protect, preserve and improve the quality of the environment in the community as well as the reduce methane production in order make an impact on climate change. This fits well with what is known as the “head-of-pipe approach”—prevention rather than collecting and treating the gas after it is produced. Notwithstanding this, there is still a requirement to collect and treatment any landfill gas that may be produced.
Work has also been undertaken by the technical adaption committee, with input from all Member States, to introduce a uniform waste acceptance procedure to reflect the landfill’s classification as shown below The Member State must define the operator’s obligations during the after-care period. The key areas to meet these objectives are:
Landfill classification
The diversion of biodegradable municipal solid waste from landfill
The reduction and control of direct emissions
The Landfill Directive specifies three types of landfills:
Inert landfills—accepts waste that does not undergo any significant physical, chemical or biological transformations after deposit.
Hazardous landfills—accepts the deposit of hazardous waste only as defined by the hazardous waste directive and the hazardous waste catalogue. One of the landfill directive drivers was to stop the joint disposal or co-disposal of hazardous and non-hazardous waste which had been practiced widely and successfully in the UK as this was perceived to pose an unnecessary risk to the longterm integrity of the landfill and the surrounding environment.
Non-hazardous landfills— for the disposal of all other wastes that are not inert or hazardous with the exception of inert waste that might be used for operational or engineering purposes. This includes municipal, commercial and industrial waste and stabilised non-reactive hazardous waste to be deposited in self-contained cells. These are wastes such as asbestos cement and plasterboard (gypsum).
Although this might seem straightforward, each Member State had its own definitions for each of the waste streams with very little similarities. For instance, the UK did not have a definition for municipal waste; they only had a definition for household waste, which did not exactly fit with the European definition. Now, 12 years after the directive was transposed into UK law, the definition has been revised, when the UK has been required to divert biodegradable municipal waste away from landfill and report on progress.
Municipal Biodegradable Waste (BMW) Diversion Targets
The diversion targets for BMW as set by the landfill Directive on all Member States are as follows:
• By 2006 (2010) BMW reduced to 75 percent of 1995 levels
• By 2009 (2013) BMW reduced to 50 percent of 1995 levels
• By 2016 (2020) BMW reduced to 35 percent* of 1995 levels
* Council to review this diversion target two years prior to target date
Although the diversion targets for biodegradable municipal waste in the northern European member states was relatively easy to achieve, it was recognized that a number of countries were so reliant on landfill as a disposal option that it would have been particularly onerous for them to achieve the targets within the timeframe. Therefore, for countries who were landfilling more than 80 percent of their biodegradable municipal waste in 1995, the target was moved back by four years which are the dates shown in brackets. The UK was one of these countries.
The final target set for 2016 will be reviewed in 2014 and it is being widely reported that this might become zero as some Member States have already introduced this into their own legislation.
Tools to Aid Diversion
Fiscal measures such as landfill tax are not uncommon. Currently, the landfill tax applied in the UK for active waste—waste being deposited at on-hazardous waste landfills—stands at £64 (US$104) per ton and will rise by £8 (US$13) per ton for each of the next two years. This has recently had a dramatic effect here in England since now only 40 percent of the municipal waste is landfilled, which is some achievement when you consider that in 2001 it was well over 80 percent. The rest is recycled, re-used, composted or used to produce energy. Landfill bans are becoming commonplace with a uniform EU directive ban on liquids. Some Member States currently ban organics and in the UK the possibility of banning wood waste is being considered. For Local Authorities in England and Wales, the government department for food and rural affairs set annual statutory household waste diversion targets for each of its local authorities. However, progress has been so good that these have now been withdrawn and the government believes that the landfill tax is now the only driver necessary.
Environmental Protection Measures
One of the requirements of the Landfill Directive is to protect, preserve and improve the quality of the community environment which can be achieved through engineering, water control and leachate management and landfill gas control. These measures are to be achieved using the annexes described in the directive. Annex 1 of the directive says that each class of landfill shall have a geological barrier engineered to the following specification:
Inert landfill : k = or < 1 x 10-7 m/s, thickness = or > 1m;
Non-hazardous landfill*: k = or < 1 x 10-9 m/s, thickness = or > 1m; and
Hazardous landfill*: k = or < 1 x 10-9 m/s, thickness = or > 5m
*Requires an additional artificial sealing liner and a drainage layer = or > 0.5m thickness
For the protection of the environment from leachate, Annex 1 requires that there are measures in place to:
Prevent precipitation entering the landfill body
Prevent surface and groundwater entering the landfilled waste
Collect contaminated water and leachate
Treat contaminated water and leachate
However, this is no more than what would be expected from good landfill practice. Bunds, berms, cut-off trenches and capping will all deliver these requirements together with the engineering outlined previously.
A further requirement from Annex 1 is to treat and manage any landfill gas that is produced. Clause 4.2 is quite specific in saying that the landfill gas must be treated and used. The measures must include:
Controlling the accumulation and migration of landfill gas
Collection from all landfills receiving BMW
Treatment and use
Collection and treatment must minimize the risk to human health and the deterioration or damage of the environment.
Conclusion
The measures described will contribute to the aims of the Landfill Directive to reduce the negative effects of landfilling by:
Clearly defining the engineering criteria to contain emissions
Defining the engineering requirements to prevent the ingress of ground and surface waters
Providing for the treatment and use of landfill (biogas) gas
However, it does not completely deliver the need for sustainability. For example, the exclusion of liquids will slow down the degradation of the biodegradable matter resulting in a dry tomb landfill requiring long-term management way beyond that of one generation. Furthermore, the concept of a hazardous waste landfill is nothing more than hazardous waste storage, which will in perpetuity pose a potential threat to the environment.
There is little doubt that overtime the landfilling of biodegradable municipal waste within the European Union Member States will cease. What is not so certain is whether the same can be said for industrial and commercial waste having the same properties as municipal waste as this will depend very much on how hard any fiscal measures might bite. However what we can be sure of is that the landfill legacy will remain with us for many years to come requiring long-term management of the emissions.
Derek Greedy is the Chair of the International Solid Waste Association’s (ISWA) Landfill Working Group. He is a Chartered Chemist and a Chartered Waste Manager who has worked in both the private and public sectors of the waste and resources management industry in the UK since 1975, The Working Group on Landfill (WGL) focuses on the design, construction, regulation and management of landfills, both for industrial and developing nations. Management issues include operations, closure, and post-closure issues, including ground-water monitoring and testing, leachate management, landfill gas management, as well as the quantity and quality of the wastes landfilled. Derek can be reached at [email protected] or visit www.iswa.org.