Hannah Fraser assesses how the Groundwater Daughter Directive will affect land remediation in the UK.
Contaminated land has a deleterious effect on groundwater quality, and proposed new EU legislation will form a new driver for land remediation. Proposals for the Groundwater Daughter Directive, which are currently being drawn up, will deal directly with the protection of groundwater against pollution.
The directive is now at consultation stage, and the Environment Industries Commission (EIC) is liaising with Defra regarding the likely impact of the legislation on the environment industries and requirements for land remediation.
The new legislation addresses the requirements of Article 17 of the Water Framework Directive (WFD), which came into force in October 2000. The overall objective of the WFD is the protection of water resources, enhancement of the status of aquatic ecosystems and promotion of sustainable water use.
Of particular importance is the new requirement to improve water quality to defined standards rather than just preventing further deterioration.
Article 17 requires that measures shall be adopted to prevent and control groundwater pollution. Such measures are designed to achieve 'good groundwater status' within 15 years of the directive coming into force, and will enforce the protection, enhancement and restoration of groundwater bodies.
The Groundwater Daughter Directive aims to improve and protect groundwater quality through a combined approach of setting emission limit values and applying environmental quality standards (EQSs).
Compliance with new EQSs is likely to result in a requirement for land remediation at sites that are not currently identified as requiring remediation. Additionally, the effects of contaminated land on diffuse pollution will require a shift in emphasis on the objectives of contaminated land clean-up.
EIC recently attended a workshop held by Defra on Contaminated Land and Diffuse Water Pollution. It was recognised that land contamination provides a large source of diffuse pollution, but there is little agreement on the scale of its impact.
In particular, little is known regarding the potential impact of many small sites that have been remediated as 'fit-for-purpose' but may still have a potential impact on groundwater quality.
In dealing with diffuse pollution in order to achieve good groundwater status, there is likely to be a requirement to address large industrial areas where historical land use has resulted in widespread land contamination, often with no clear liability holders. Integrated clean-up strategies could be required to undertake widescale land clean-up, although questions remain unanswered on who will pay for land remediation in circumstances where there have been many site owners/operators or where remediation timescales are long.
At present, land remediation is driven by redevelopment and the planning process, or by Part IIA of the Environmental Protection Act (1990), both of which support a risk-based approach. The EIC has expressed concern to Defra that, while some elements of the directive's proposals are consistent with risk-based approaches, proposed groundwater quality standards and thresholds are not wholly consistent with risk-based principles. They may, therefore, not meet the need for an appropriate balance of risks, costs and benefits in the interests of the protection of human health and the environment.
There remain some concerns over how EQSs will be set, with a strong desire among stakeholders and regulators for realistic, risk-based standards to be set locally rather than at European Community level.
While the new directive is likely to drive additional site clean-up, there is the possibility that significant sources of pollution will not be addressed by the legislation. This is because the chemical status of groundwater bodies is to be determined on the basis of an average concentration for an entire groundwater body, and average concentrations may mask locally significant impacts to groundwater quality.
Defra has recently undertaken a partial regulatory impact assessment (RIA) examining the Groundwater Daughter Directive proposals, and the costs of measures to remediate groundwater contamination. It was estimated that 777 sites may require groundwater remediation, based on the number of point sources known to have caused groundwater pollution, at an estimated cost of £3.5bn.
EIC has canvassed its members for a more up to date cost estimate for groundwater remediation procedures and to provide comment on the current consultation draft.
The new directive has not yet been finalised, but it is clear that it will have a considerable impact on the objectives, methods and regulation of contaminated land risk assessment and remediation, affecting both problem holders and solution providers.
The EIC has recommended to Defra that there should be an explicit assessment of the directive on the environmental technology and services sector, and will continue to monitor the implications of the directive as it progresses towards final legislation.
Helen Fraser is senior hydrogeologist with Environmental Simulations International.