Planning and management of environmental remediation (ER)

To ensure that protective measures can be quickly and efficiently imple­mented to mitigate the adverse effects of an accident or other forms of long-term contamination at a nuclear site requires good planning, clear strategies and a good managerial team. Preparations for environmental remediation (ER) should, if possible, be done in two phases: preliminary planning, which should be available as part of normal operation or emer­gency preparedness for each nuclear facility; and detailed remediation plan­ning, which takes into account site (and accident where applicable) specific

Event site

Year

International Nuclear Event Scale (INES) rating

Impact on environment

Environmental remediation

Fukushima,

Japan

2011

7

Extensive contamination, evacuation

Started

Chernobyl,

Ukraine

1986

7

Extensive contamination, evacuation

Underway

Kyshtym, Russia

1957

6

At least 22 villages were exposed to radiation, a total population of around 10,000 were evacuated

Fragmentary information, contaminated soil was excavated and stockpiled in fenced enclosures

Goiania, Brazil

1987

5

Houses and scrapyards contaminated

Topsoil had to be removed from several sites, and several houses were demolished

Three Mile Island, USA

1979

5

Not lasting

Environmental control

Windscale, UK

1957

5

Not lasting

Environmental control

 

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Level 7: Major accident. Major release of radioactive material with widespread health and environmental effects requiring implementa­tion of planned and extended countermeasures.

Level 6: Serious accident. Significant release of radioactive material likely to require implementation of planned countermeasures. Level 5: Accident with wider consequences. Limited release of radioactive material likely to require implementation of some planned countermeasures.

information. The two types of planning can be complementary and both are important in minimizing the detriment to society.

Life cycle assessment (LCA) is a systematic method used extensively for evaluating environmental effects of a technology or production process from cradle to grave. The method is gaining widespread acceptance in the field of supporting systems for environmental decision making. Indeed, the way environmental problems are seen and tackled by such an approach comes within the framework of sustainable development thinking. LCA actually enables listing and quantification of environmental burdens (radio­logical and non-radiological) and related impacts over the whole life cycle of a product, process or activity, from the very beginning to the end.

It is clear that LCA, when used by those who fully understand the tech­nology being analysed, can be a useful addition to the process designer’s toolkit. It ensures that pertinent questions are asked at the design stage and it can show where the environmental emissions/impacts occur and from where they arise within the process. If not addressed in the design stage, LCA can also be valid during on-going operations. With this knowledge, the process designer, or the operator of an existing process, can then set about minimizing these emissions/impacts, taking into account the overall life cycle of the operation. It is expected that early consideration and manage­ment of expected or on-going environmental impacts will reduce time and costs of remediation in comparison to actions taken only at the end of service life of a nuclear facility. A website devoted to LCA can be found in US EPA (2012).

From the radiation protection perspective, remediation projects are driven by two leading principles: justification and optimization. The first principle requires prior consideration of the benefit that would be achieved by the remedial action and also consideration of the harm it may eventually cause, in its broadest sense. In a very simple way, it can be stated that reme­diation should produce more good than harm. The second principle applies to the range of justified remedial options for which the net benefit would be positive. The optimum remedial option would be the one for which the net benefit is maximized. However, cost-benefit analysis methodology is limited to quantitative comparisons between the protection costs and the detriment costs. Some other approaches, namely multi-attribute utility anal­ysis (see Section 4.5.1) allows the use of utility functions and introduces factors which are not easy to quantify in monetary terms as required in cost-benefit analysis (Fernandes et al, 2013).

In many cases, the above principles are not fully considered in the deci­sion-making process. Appropriate balance between the benefits and costs of remediation projects are particularly important in countries in which some sort of remediation programme is needed, as the costs of remediation (capital and labour costs) will have to compete with the benefits that the application of that same amount of money would produce if directed to other purposes; for example, building schools or hospitals, or improving the existing infrastructure. It is clear that optimization may dictate the extent and end state of the remediation project, and so affect the generation and management of radioactive and other waste.

In addition to this, from the institutional perspective, it has to be kept in mind that remediation projects will entail longstanding administrative, monitoring and enforcement requirements; therefore the presence of solid institutions that will need to bear the responsibilities associated with the institutional controls is necessary. All these together may be subjected to the consideration of a full range of stakeholders so that they can be aware of the various implications of the implementation of an ER project. These discussions should take place under a well-established regulatory frame­work and clear allocation of responsibilities.

Accordingly to the IAEA Safety Glossary (IAEA, 2007), remediation is defined as any measures that may be carried out to reduce the radiation exposure from existing contamination of land areas through actions applied to the contamination itself (the source) or to the exposure pathways to humans. A very important element in the overall remediation concept, as defined by the IAEA, is that complete removal of the contamina­tion is not implied. Needless to say, the generation and management of wastes from such projects will be heavily impacted by the extent of removal works.

The terms ‘rehabilitation’ and ‘restoration’ may also be used, but they imply that the conditions that prevailed before the contamination can be achieved again, which is not really necessary. Instead this chapter uses the term ‘remediation’, which does not have these implications. ITRC (2002) discusses decision-making methodologies and case studies as applied to the clean-up of radioactively contaminated sites.

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