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4.2.6 Regulatory aspects

Contents
4.2.6.1 National and international regulations
4.2.6.2 Regulations affecting the implementation of a remediation plan
4.2.6.3 Environmental impact assessment
4.2.6.4 Assessment of worker and public exposures
4.2.6.5 Regulatory controls

4.2.6.1 National and international regulations

National laws and regulations on environmental protection, human health, radiation safety and occupational safety will need to be considered and adhered within strategies for the remediation of contaminated sites. It is unlikely that any remediation strategy that does not fit within the regulatory framework will be acceptable to either the regulatory bodies or the general public, even if all other assessment factors, for example, health impact assessment, technical feasibility, waste acceptance criteria and disposal routes, are acceptable [IAEA-2006b].

Most countries do not have specific regulatory regimes to deal with, e.g., mixed radioactive and non-radioactive contamination. In many cases, separate regulatory regimes operate for the two types of contaminant. The lead regulator is either the one responsible for radioactive materials or is selected on the basis of the judged or perceived dominant source of risk or hazard. As a result, the regulatory approach is often to assess and deal separately with the two types of constituent within any mixed contamination on any site. One of the two classes of contaminant may, in practice, dominate, dependent upon the controlling acceptable limits on soil, water and air from releases. However, the regulatory problems can sometimes be simplified by subdividing the site into areas where one or the other type of contaminant dominates the risks and hence controls the remedial strategy.

The degree of regulation, regulatory control and guidance for environmental remediation projects for sites with mixed contamination varies markedly from country to country. The variations frequently reflect the status and the scale of any nuclear power and weapons development, the significance of radioactivity issues, the size of the country and the degree of autonomy exercised by regional governments over environmental issues. Protection of the public, operational safety and environmental protection are key areas for regulation. In many European Union (EU) countries, there are regulatory bodies, with specific responsibilities for overseeing the operational safety of all works, including remediation activities, at major commercial nuclear sites, for example, power reactors and nuclear fuel fabrication and reprocessing facilities. Their remit may extend to nuclear weapons development and production facilities. For other facilities, which are not primarily nuclear facilities and where the use of radioactive materials is secondary to that of chemicals or other hazardous substances, the prime regulatory authority for safety in all operational works is frequently the one with responsibility for general workplace safety. For protection of the environment, which includes any discharges from sites to the air, water or land, waste disposals, etc. with potential impacts on the off-site public, flora and fauna, other regulatory bodies may be involved in environmental remediation. Local regulatory authorities, for example individual state or district environmental protection departments or agencies, may also have significant roles.

The boundaries between the responsibilities of the different regulators may not always be clear where environmental remediation projects involving mixed waste sites are to be considered. In addition, the level of input and the importance of the different regulators may often vary over the project life. These issues may frequently be resolved by agreements between the different regulators to work in unison or delegate the lead at particular sites or projects to one another, dependent upon the nature of the problems prevailing at the specific site. However, it is often beneficial at the start of any project to have the full involvement of all potentially interested regulatory bodies to ensure a common understanding of the problems, the proposed solutions and the constraints from different regulators.

4.2.6.2 Regulations affecting the implementation of a remediation plan

Implementation of remediation projects can potentially result in environmental impacts additional to those associated with mixed contamination alone. As a result various other regulatory permits and authorizations may be required [IAEA-2006b].

Some techniques involving the re-injection of treated water into the geological formation may need a water disposal permit or license. Any operation that typically can or will result in emission is likely to attract regulatory oversight. Permits, authorization or licenses related to the remediation process could be needed for operations such as:

  • Construction of wells;
  • Extraction of water and also discharge of treated water;
  • Re-injection of treated water into a geological formation;
  • Introduction of materials to aid remediation; the materials may need to be of an approved standard, for example, food quality;
  • Gaseous discharges; supplementary assessments including air plume modelling, environmental impact assessments and the need for off-gas treatments;
  • All types of excavations (checks for underground services in utility company records and physical surveys for underground services);
  • On-site treatment of contaminated soil;
  • For remediation operations in sites of historical interest, archaeological permits may be needed.

Remediation work normally would be organized and carried out according to locally or internationally recognized best practice. This should help to ensure that environmental impacts accord with the as low as reasonably practicable (ALARP) principle [IAEA-2006b].

4.2.6.3 Environmental impact assessment

A degree of broader regulatory control is exercised over major projects, including remediation of sites, through national requirements for assessments of environmental impacts before any new project is undertaken. In countries of the European Union, there are European Directive requirements for environmental impact assessments (EIA). Such environmental impact assessments may not only assess and quantify environmental impacts but may also justify the selection of the chosen remedial strategy through critical review of the potential options and quantification of their potential impacts. The environmental impact assessments can also identify measures to be taken to mitigate impacts and reduce them to the lowest practicable levels. Regulatory bodies are often statutory consultees to the environmental impact assessments and may, therefore, also influence the proposed remedial works through this route. In some countries, major remedial projects are treated as new developments on land and are also covered by land use planning regulations. The requirements for environmental impact assessments form part of these regulations, as do controls on potential public nuisances [IAEA-2006b].

4.2.6.4 Assessment of worker and public exposures

Remediation of sites contaminated with hazardous and radioactive substances can result in the exposure of workers and potentially the public to physiological and possibly physical harm. Radiological, chemical, biological and some hazardous materials, for example asbestos, can give rise to the former, while corrosive, flammable and explosive constituents can give rise to the latter. At sites with ongoing activities, the exposure of workers directly involved in the remediation work and elsewhere on the site is frequently controlled through workplace regulations. Relevant national regulations often cover chemical and toxic substances hazardous to health, ionizing radiation, environmental nuisances, for example odours, noise and traffic, and construction type risks. All of these factors need to be considered in operational safety and require full assessment as in a safety case. When planning and licensing a remediation strategy, reductions in public exposures may be balanced against the exposures incurred by workers as a result of the remediation action [IAEA-2006b].

Assessments of workers and public exposures are often necessary for regulatory approvals during the period work is carried out and finally for acceptable residual levels of contamination. These are usually determined by safety and risk assessments that address in separate parts the impacts of the radioactive and non-radioactive hazardous components. Some regulators may also prescribe methodologies and computer codes for undertaking assessments of acceptable residual levels of chemical or radioactive contamination. The acceptable residual levels often depend on scenarios for future site use and are subject to optimization. In addition, in some cases regulators and site liability owners/operators have been working together to develop guidance on agreed best practice on the characterization, assessment and remediation of contaminated sites. Synergistic effects between radioactive and chemical contaminants are not generally considered in these assessments unless specific data are available. The risk assessment methodologies used for assessing operational safety during remedial work and environmental impacts before, during and after such work employ very similar exposure pathway models for both types of contaminant. They also use the same risk basis for acceptability, i.e., 10-4 – 10-6 lifetime risk.

Information about safety and health risks and associated guidance can be obtained from standard reference sources, regulatory standards, medical surveillance, safety studies, toxicological data and epidemiological studies. Most of the guidance is national, with the exception perhaps of the European Union, where an internationally agreed body of regulations is being developed. In a similar way, existing international standards and guidance are usually focused on either radioactive or hazardous materials.

An IAEA Safety Requirements publication provides radiological criteria for aiding decision making on the remediation of areas contaminated by past practices and accidents [IAEA-2007a]. In some countries remediation objectives for contaminants in soils have been implemented. There are international standards for acceptable levels of some radionuclides and toxic chemicals in drinking water. Databases have been established for chemical and hazardous substances, which relate their toxicity to acceptable levels in soils and water.

An IAEA Basic Safety Standards and its derivative publications is valuable reference for radiological risks [IAEA-1996]. There are international recommendations on exposure limits for workers and the public to radioactive substances.

There are also similar national standards in many countries controlling such exposures to toxic substances. Given similarities in the latter, these are effectively internationally accepted standards.

4.2.6.5 Regulatory controls

Institutional controls may be implemented to reduce or eliminate potential threat of exposure to human health. The following kinds of institutional controls have been established in some countries and may be considered to prevent exposure to contaminated groundwater [IAEA-1999a]:

  • Regulatory restrictions on construction and use of private water wells, such as well construction permits and water quality certifications;
  • Acquisition of property by the government from private entities;
  • Exercise of regulatory and police powers by governments, such as zoning and issuance of administrative orders;
  • Restrictions on property transactions, including negative covenants and easements;
  • Non-enforceable controls, such as well use advisories and deed notices;
  • Relocation of affected populations (in extreme cases).

The effectiveness and reliability of these controls should be evaluated when determining whether rapid remediation is warranted. If there is adequate certainty that institutional controls will be effective and reliable, there is more flexibility to select a response action that has a longer restoration time frame or a determination that no remedial action is required.