When evaluating the various nuclear technology options available, it is important to keep in mind that nuclear power also has important potential in the area of non-electric applications such as desalination, hydrogen pro­duction, district heating, oil refining, tertiary oil recovery or coal gasification (see Fig. 9.11). Indeed, there is experience with nuclear power in the heat and steam market in the low-temperature range, i. e. desalination and dis­trict heating. An extension appears possible on a short term in these areas as well as for tertiary oil recovery. The petrochemical and refining industries represent another huge potential with their growing demand for hydrogen and process steam due to the increasing share of fossil fuels such as heavy oils, oil shale or tar sands entering the market. In the high-temperature heat market, nuclear is also applicable to the production processes of liquid fuels or of hydrogen by steam reforming or water splitting, compatible with the needs of the transportation sector. The feasibility of steam reforming of methane or coal gasification under nuclear conditions was already success­fully demonstrated.

There are many other industrial sectors (such as paper and pulp, food industry, automobile industry, or textile manufacturing) which have a high demand for electricity and heat/steam at various levels of temperature and pressure. In such industrial processes, the reliability and availability of the

energy supply is essential, demanding the continuous operation of their process units approaching 100%. The temperatures required cover a wide spectrum. With respect to the required capacity, 99% of the industrial users need thermal power of less than 300 MW, which accounts for about 80% of the total energy consumed. Half of the industrial users even demand thermal power in the range of less than 10 MW. Ensuring supply security by diversification of the primary energy carriers and, at the same time, limit­ing the effects of energy consumption on the environment will become more important goals in the future.

In principle, any type and size of nuclear reactor can be used as heat source for various processes and applications. No technical impediments to coupling nuclear reactors to such applications have so far been observed, although a number of safety-related studies of coupled systems may still be necessary. Different types of nuclear reactors provide a different range of coolant temperatures. The higher the temperature, the larger is the range of applications and products. Current Light Water Reactors (LWR) are characterized by maximum temperatures of less than 320°C, only allowing steam production at a lower quality. Hence, they are mainly used for elec­tricity generation with occasional steam extraction. In Fast Breeder Reactors (FBR) the coolant reaches a higher temperature of around 500°C, while High-Temperature Gas-Cooled Reactors (HTGR) are able to provide steam up to a temperature of 950°C. It is an area where nuclear energy specifically from HTGRs could play a major role in future (Fig. 9.12).

The main challenges at present are to combine nuclear power and non­electric applications into a single strategy and to establish the transition technologies from present industrial practice to emerging new resources in order to stabilize energy cost. The renewed interest in nuclear power pro­duction may lead to an increased role for nuclear energy in the area of non-electric applications, which currently are almost entirely dominated by fossil fuel energy sources. Among other advantages (including less environ­mental impact and high energy content of nuclear fuel) of the use of nuclear energy for non-electric applications is that nuclear reactors offer process heat at a wide spectrum of temperatures from some 200°C to 1000°C, which covers practically the whole range required for most non-electric applica­tions, including waste heat which can be harnessed in some very low — temperature non-electric applications such as seawater desalination.

Cogeneration may become the most suitable option for non-electric applications. In this case the steam and electricity can be produced with a single nuclear plant. The cogeneration mode has several practical advantages: an increased plant thermal efficiency, the possibility of varying the heat supply according to demand and an easier implementation, as almost all nuclear reactors for electricity production can be adapted. Thus the first nuclear non-electric applications are likely to be of the cogenera­tion type. This has been confirmed by the experience with nuclear district heating and desalination.

Examining Figs 10.6 and 10.7, it is apparent that the most frequent abnor­mal events are likely to have zero health consequences to the public. However, these events can be very expensive to the operating organization, because they often result in power decreases or reactor shutdown. (Most of the electricity production cost arises from debt retirement of the plant capital cost; operating costs are a relatively small part of the total.) Plant management has a very strong motivation toward reduction of these minor malfunctions. Obviously, this reality exerts a strong positive effect on overall plant safety motivation. The mid-frequency range of malfunctions also exerts a strong positive influence on plant safety — there is a possibility that such accidents might result in some damage to the plant, or at least may lead to extended outage time for inspection, repairs or plant modifications. This is the frequency range in which probabilistic safety analysis is most effective, as we will see in Section 10.4.

The ‘disaster range’ of accident events shown in Fig. 10.6 is the range that concerns safety regulatory agencies the most; it is the range in which the reactor accident might lead to human fatality. In common practice, this is the frequency range (~10-4 per year and lower) over which the special safety systems provide the primary defence against health consequences. In US practice, this range is identified as the ‘severe accident’ range, which includes at least some degree of reactor core disruption.

In the early history of the nuclear industry, this disaster range received an undue amount of attention on the part of designers and regulators. The reason was that accident models were very simple and extremely conserva­tive, so that the predicted consequences were correspondingly large. During the past several years, more exact and realistic predictions of consequences have been made, and so the predicted consequences have become much smaller. Nevertheless, regulatory agencies have tended to continue applica­tion of the very rigid and conservative acceptance criteria that were devel­oped during the time when analysis models were crude and overly conservative. The nuclear reactor safety field is now in transition toward more realistic modeling. It is expected that these plants will eventually be proven to be considerably safer in terms of human health than they were originally thought to be.

In the end, then, the question of whether or not nuclear energy will be installed on the very large scale needed to replace today’s energy supply from oil, natural gas and coal will probably be determined by a balance of fear — between fear of the technology and the fear of falling short of the high level of supply required to maintain the people of the world in good health and spirit.

11.1.1 Quantities and units

A unique characteristic of radiation protection is the full international harmonization of the relevant quantities and units. This has been achieved under the influence of the International Commission of Radiation Measurements and Units (ICRU), a sister organization to ICRP (ICRU, 1938, 1954, 1962), and is unique vis-a-vis other pollutants.

NPPs are characterized by the presence of radioactive substances, the amount of which is described by the quantity termed activity and measured in the unit termed becquerel — although, in the past, the unit curie was and still is widely used. One becquerel represents an extremely small activity; for instance, one becquerel is the activity of potassium (which is a long — lived, naturally radioactive element) contained in less than one-tenth of one banana! (Conversely, 1 curie represents a significant activity as it equates to 37 thousand million becquerels.) Although varying among plants, NPPs currently discharge into the environment an average activity of around a hundred million million becquerels (or terabecquerels, TBq) per kilowatt year of electrical energy produced, mainly of short-lived radioactive noble gases.

NPP materials with activity emit radiation that may expose both workers and members of the public and may be delivered from outside the person’s body (external exposure) or by radioactive substances arising from those materials that may be incorporated into the body via inhalation or inges­tion, or through open wounds or the skin (internal exposure). The potential health consequences on people caused by their exposure depend on the amount of radiation received, and also on the types of radiation involved and the organs exposed.

The amount of radiation is measured in terms of the quantity termed the radiation dose, and that received by human tissues is termed the absorbed dose and is assessed in units called grays (in the past, the unit rad was used) or in its sub-multiple, the milligray. One milligray is approximately the lowest annual dose absorbed by a human being due to exposure to natural background radiation.

Different types of radiation have different effectiveness to induce damage and, therefore, the absorbed dose has to be weighted by radiation weighting factors, wr, to take into account the effectiveness of various radiation types. The resulting weighted quantity is termed the equivalent dose.

Table 11.1 (ICRP, 2007a) presents the currently recommended radiation weighting factors, wR, which gives a general idea of the radio-efficiency of the various radiation types. It is noted that the main radiation types in NPP exposures, which are у rays, i. e. photons, and в particles, i. e., electrons, have a weighting factor equal to 1. The weighting factor for neutrons can be high depending on their energy, but exposure to neutrons is important for some NPP equipment but normally not for people.

Similarly, different organs and tissues have different sensitivity to radia­tion exposure, and therefore the equivalent dose has to be weighted by tissue weighting factors, wT, to take into account the various sensitivities to radiation of various organs and tissues. The quantity resulting from

cases the absorbed dose in gray or milligray should be used. Radiation protection standards usually contain universally agreed nominal coeffi­cients or factors for converting activity and particle fluence into absorbed dose and also equivalent dose and effective dose.

Figure 11.1 (adapted from ICRP, 2007a) illustrates the interrelation among the radiation protection quantities, including the nominal conver­sion factors.

The radiation protection quantities are not directly measurable. Instruments for assessing doses in people or in the ambient environment are usually calibrated against physical operational quantities rigorously defined by ICRU and incorporated in international standards. These are the personal dose equivalent and the ambient dose equivalent. They are also expressed in sieverts and, numerically, they approximately correspond to the radiation protection quantities. The operational quantities are formally used at NPPs for verification of compliance with standards.

For reasons of simplification, this chapter will use the term dose to mean generally and indistinctly any dose quantity and will express this quantity mainly in the unit millisievert (mSv).

According to the IAEA recommendations, the nuclear emergency plans

usually consider several classes of emergency, which depend on the expected

consequences of the accident scenario considered for planning:

• General emergencies involve an actual or substantial risk of release of radioactive material or radiation exposure that warrants taking urgent protective action off the site. Upon declaration of this class of emer­gency, action shall be promptly taken to mitigate the consequences of the event and to protect people within on-site and off-site zones.

• Site area emergencies involve a major decrease in the level of protection for those on the site and near the facility. Upon declaration of this class of emergency, action shall be promptly taken to mitigate the conse­quences of the event, to protect people on the site and to make prepara­tions to take protective action off the site if this becomes necessary.

• Facility emergencies involve a major decrease in the level of protection for people on the site. Upon declaration of this class of emergency, action shall be promptly taken to mitigate the consequences of the event and to protect people on the site. Emergencies in this class can never give rise to an off-site area or general emergency.

• Alerts involve an uncertain or significant decrease in the level of protec­tion for the public or for people on the site. Upon declaration of this class of emergency, action shall be promptly taken to assess and mitigate
the consequences of the event and to increase the readiness of the on-site and off-site response organizations as appropriate. Alerts include events that could evolve into facility, site area or general emergencies.

Design and implementation of the emergency plans are carried out in three phases:

• The planning phase consists of a detailed analysis of the situation that can occur at the facility. The result of this analysis is used to define the characteristics of appropriate emergency measures, to mitigate the con­sequences of every credible event. The results of the analysis are used to establish the emergency plan that accurately describes the organiza­tion in charge of implementing countermeasures; emergency actions to be taken in each case; a clear allocation of responsibilities of every individual participating in the implementation of emergency measures; intervention criteria; decision-making procedures for countermeasures implementation; definition of planning areas; and the means and resources needed for intervention.

• The preparedness phase consists of the identification, acquisition and putting into optimum use conditions of means and resources to inter­vene in case of emergency. Preparation includes also training of inter­vention personnel and maintenance of the technical, human and organizational means and resources, as well as the verification that all of them are permanently in a position to be activated. A crucial element during the preparedness phase is conducting partial or full-scale exer­cises for training the intervention personnel and verifying the appropri­ateness of emergency plans.

• The response phase consists of the activation of the emergency organiza­tion, as soon as possible, to cope with a real or simulated accident, through the implementation of countermeasures foreseen in the emer­gency plans with the available means and resources. The response phase starts with the decision of activating the plan after an accident occurs. This decision is taken by the operator in the case of on-site emergency plans and by the relevant authority in the case of off-site emergency plans. The response phase includes implementation of urgent mitigation and protective emergency measures, and undertaking appropriate reme­dial actions in the medium and long terms until bringing the situation to a safe condition. The response finishes when the normal situation has been recovered as far as possible.

Operators and public authorities responsible for the implementation of the nuclear emergency plans periodically conduct a review in order to ensure that situations that could necessitate an emergency intervention are identified, and to ensure that an assessment of the threat is conducted for such practices or situations. This review is undertaken periodically to take into account any changes to the threats within the State and beyond its borders, and to learn from experience and lessons from research, operating experience and emergency exercises.

It would be expected that once a State makes a decision to proceed with the infrastructure development (i. e., Milestone 1 is achieved), the State organizes the national means and plans needed to successfully implement its decision while progressing towards Milestones 2 and 3. If the State is contemplating whether to conclude an additional protocol to its safeguards agreement with the IAEA, it will necessarily want to understand the con­tents of the Model Additional Protocol (INFCIRC/540 (Corrected)) (IAEA, 1997a). Due to their direct relevance to drawing a safeguards conclusion, the relevant articles of the AP which cover the provision of information and complementary access will be discussed further.

The promise of electricity ‘too cheap to meter’ of the 1950s and early 1960s brought about a quasi-unprecedented enthusiasm for a new technology throughout societies around the world. It was going to open up an era of abundant and clean electricity and stop the filth and smoke of oil — and coal-fired power plants. Numerous countries launched ambitious peaceful nuclear power programmes, a trend that was further fuelled by the oil supply crises and associated price hikes of 1973 and 1979. Global nuclear generating capacity expanded rapidly beginning in the 1960s from barely 1 GW to 325 GW by 1990. During these early years, nuclear power plants were enthusiastically supported and mostly funded by governments in large part to develop and commercialize this new technology. Utility orders began to mushroom by the 1970s and expectations were that nuclear power would provide the lion’s share of electricity globally by the beginning of the twenty-first century. The order books of the nuclear industry were brimful as plant orders poured in by the hundreds.

Reality, however, proved different. Beginning in the early 1980s numer­ous orders were cancelled — even where plant construction had almost been completed — and global nuclear power faced stagnation which lasted until about 2002-03. There were many reasons for these cancellations and sub­sequent stagnation but the bottom line was economics. Given the current rising interest in nuclear power, a review of factors underlying past nuclear stagnation and whether the situation is different today than 30 years ago is in order. In essence, the following factors chiefly determined and will continue to determine the economics of nuclear power: market structure, government policy, generating costs relative to alternatives, finance, public acceptance and environmental performance.

Looking back to the 1980s, the nuclear stagnation is not attributable to a single factor but is rather the result of a combination of several (often unrelated) factors. Regarding demand, while the oil price shocks of the 1970s had been a major driver of the nuclear expansion, they also had prompted government policy mandating efficiency improvements through­out the energy system as well as the development of alternative energy sources. High fossil fuel prices not only provided incentives for accelerated exploration and development of non-OPEC oil resources but also resulted in structural economic change in many industrialized countries, i. e., a shift from energy-intensive primary and secondary manufacturing industries to tertiary (service and knowledge based) industries. The net effect of all these measures was a considerably lower growth in electricity demand which due to time lags became only evident by the early 1980s. Demand uncertainty — until then a relatively insignificant risk — became a new challenge. Risks were further compounded by the emergence of surplus generating capacity in many markets. Long lead times in power capacity planning and plant construction made it difficult to respond in a timely manner to the new demand situation. As a result many — nuclear and non-nuclear — power plant orders were cancelled or halted where construction was already underway.

At the time, electricity supply was viewed as a strategic good and most electricity utilities were government owned. In markets where utilities were privately held, strict regulatory oversight ensured cost controls, supply reli­ability and security. In either case, utilities were vertically integrated, viewed as natural monopolies without real market competition (except with other fuels). In return for quasi-guaranteed markets, utilities had a supply obliga­tion at government-controlled sales revenues. Revenues were usually struc­tured to cover actual fuel and variable operating and maintenance (O&M) costs plus, in the case of private sector ownership, a regulated (reasonable) return on capital. Through direct ownership or through the regulatory approval process, governments directly influenced investment decisions and technology choices.

In essence, privately owned utilities operated under a ‘cost plus’ scheme, i. e., they could essentially recoup all costs, including investments — even if these were higher than anticipated (unless imprudently incurred) or if demand turned out lower than projected. To that extent, the economic risk of electricity supply was entirely borne by the taxpayer. It was this low-risk framework that enabled utilities to invest in capital-intensive generating stations such as hydro or nuclear power. However, the situation changed in the 1980s, in large part in response to surplus generating capacities in many markets and the resulting widely differing rates between regional markets. Another change concerned a shift in the recognition of the different roles of public and private sector entities and their respective efficiency and effectiveness in decision making and risk management. Regulated electric­ity markets gave way to deregulation and market liberalization. Many gov­ernment utilities were privatized. Electricity market competition, unbundling of generation, transmission and distribution instead of quasi-natural monopolies became the new paradigm in many countries for addressing surplus capacity and stranded costs, reducing rate differences between regional markets and encouraging electricity trade. Competition, partition­ing and allocating risks to entities that are best positioned to manage them were hailed to improve efficiency and overall market transparency and ultimately incur lower costs to consumers. Clearly ‘cost plus’ rate setting as well as long-term investment planning and decision making became a thing of the past overtaken by short-term shareholder value optimization.

Investment in nuclear power, however, not only requires long-term plan­ning but also involves long pay-back periods and lower returns than alterna­tive investment opportunities — characteristics which proved incompatible with short-term shareholder optimization. The general retreat of govern­ment involvement (usually with longer planning horizons) in financing elec­tricity sector investment — be it because of general divesture or the many other non-energy demands on government budgets or economic transition — further reduced the attractiveness and market potentials of nuclear power.

In addition, the track record of the nuclear industry to deliver nuclear power plants at budget and on schedule was marred as construction delays and cost overruns through the 1980s often became the norm rather than the exception. The plants built in the 1970s were scaled-up adaptations of smaller demonstration plants built in the 1960s, thus effectively represent­ing a ‘first-of-a-kind’ experience. Often designs were being finalized on-the — fly during construction, resulting, at times, in widely differing final plant designs for initially identical units as different engineering approaches and design improvements provided for different solutions (NEA, 2009).

While extreme cases of cost overruns, e. g., of an order of magnitude, or delays of many years were rare, and many less extreme delays and overruns can be rationalized (see below), they brought many utilities to the brink of bankruptcy and the reputation of the industry with investors plummeted and has yet to be fully restored. Several factors — partly beyond the control of the industry — contributed to plant completion delays and cost overruns. The 1979 Three Mile Island (TMI) accident in the United States raised safety concerns and prompted regulators to toughen safety regulation. New regulatory requirements mandated upgrading of existing plants and plants under construction with additional and more complex safety features. For plants under construction this resulted in extended construction schedules and added costs; for completed plants it meant lengthy shutdowns and loss of sales revenues. Moreover, the early 1980s saw a period of two-digit interest rates and high inflation which further compounded cost overruns through cost escalation and accumulated interest during construction.

The TMI accident also adversely affected public and political acceptance and served as a wake-up call to investors about the economic and technical risks of nuclear power plants. Governments seeing their budgets stressed by cost overruns began to see the technology in a different light. The revised regulatory and plant licensing procedures also opened prospects for the involvement of civil society through public hearings, environmental impact assessments and legal intervention. Especially, anti-nuclear groups seized the opportunity and over time perfected the effectiveness of legal interven­tion, causing further delays and added costs.

As regards overall energy supply, the stepped-up investments in non- OPEC oil exploration and production capacity as well as the delayed effect of efficiency and performance standards began to impact the international oil market: lower demand was met by rising supplies exerting downward pressure on prices. This situation culminated in 1986 when OPEC lost control and global oil prices collapsed (and gas and coal prices followed suit), compromising the economic rationale for nuclear power. Plentiful cheap oil and gas on the one hand, and the advent of low capital cost, highly efficient combined cycle gas turbines (CCGT) with smaller unit sizes and considerably shorter construction and payback schedules than nuclear power (and coal), on the other hand, offered utilities less bulky and lower risk investment opportunities. Smaller unit sizes were highly welcome in markets with uncertain electricity demand prospects, and high returns were consistent with short-term profit and shareholder value maximization.

With plentiful cheap oil and gas available, energy supply security — the prime driver of nuclear power in the 1970s — was no longer a national policy concern in most countries. Environmental performance also appeared less a matter of concern. Policies targeted at controlling sulphur and nitrous oxide emissions chiefly responsible for local air pollution and regional acidification had taken effect already in many industrialized countries and the threat of climate change had not yet been high on the international environmental agenda.

In summary, the economics of the day had already disfavoured nuclear power with investors when the disastrous Chernobyl accident of April 1986 — like the straw that broke the camel’s back — also turned the public at large against the technology. Many reactor orders not already cancelled for eco­nomic reasons were now stopped due to safety fears and several countries decided to abandon their national nuclear power programmes. The global nuclear power situation was further set back by the disintegration of the Soviet Union and consequent economic collapse.[87]

508 Infrastructure and methodologies for justification of NPPs

Following the advent of the EURATOM Treaty (establishing the European Atomic Energy Community), European Union regulation in the field of nuclear installations has historically taken the form of EU Directives. As with international law, EU Directives are not directly applicable in Member States — they must be transposed into the national legal system by national implementing legislation. Two legal concepts have been particularly influ­ential in the regulation of the environmental impacts of nuclear installations

— Strategic Environmental Assessment and Environmental Impact Assessment. Both of these legal concepts are discussed in further detail below, as well as the national legislation which implements the relevant EU Directives in the UK.

European Union Strategic Environmental Assessment (SEA)

Strategic Environmental Assessment (SEA) is a mandatory legal require­ment in the European Union in respect of plans or programmes which are adopted by EU national public authorities. The SEA regime is a relatively recent concept that is derived from the Directive on strategic environmen­tal assessment (SEA Directive 2001/42/EC), which was transposed into English law by the Environmental Assessment of Plans and Programmes Regulations 2004 (SI 2004/1633). The objective of the Directive is to ‘provide for a high level of protection of the environment’ by ensuring the ‘integra­tion of environmental considerations into the preparation and adoption of plans and programmes’ (SEA Directive, 2001, Article 1). ‘Plans or pro­grammes’ is very widely defined and covers many types of activity, including many kinds of government policy statements.

The SEA Directive provides that an environmental assessment is to be carried out for all plans and programmes which are likely to have significant environmental effects. The assessment is to be completed prior to the plan or programme being adopted so as to ensure that environmental considera­tions are fully integrated in the process from the outset (SEA Directive, 2001, Article 4(1)), and reasonable alternatives should be identified, described and evaluated where appropriate, taking into account the objec­tives and geographical scope of the plan or programme (SEA Directive, 2001, Article 4(1)).

Plans and programmes requiring SEA

The SEA Directive and its transposition into the domestic legal systems of Member States of the EU establishes a statutory test to determine whether an SEA assessment is required:

1. Is there a specific legislative, regulatory or administrative requirement for the plan or programme?

2. Does the plan or programme set a framework for future development consents?

3. Is the plan or programme ‘likely to have significant environmental

effects?’

4. Does the plan or programme relate to a subject matter contemplated by the Directive? Plans or programmes prepared for energy purposes are expressly covered by the SEA Directive and so, in the context of the development of new nuclear power programmes, SEA will often feature as a mandatory requirement. (SEA Directive, 2001, Articles 2(a), 3(1) and 3(4))

A key issue for national, regional and local authorities therefore is to determine (in advance of approval) whether the proposed plan or programme is subject to the requirement of an SEA assessment. This will be important since SEA carries with it certain minimum administrative and procedural steps and requirements for consultation that lead to the produc­tion of formal documents such as the Environmental Report (akin to the Environmental Statement in a project-level Environmental Impact Assessment — see below). In the United Kingdom, a local authority’s decision may be challenged by way of judicial review if, for example, it incorrectly determines that an SEA is not required.

The United Kingdom government has taken the view that pure state­ments of general government policy do not fall within the scope of the SEA Directive, such as the Energy White Papers of 2006 (Department of Trade and Industry, The Energy Challenge: Energy Review Report, July 2006) or 2008 (Department for Business, Enterprise and Regulatory Reform, Meeting the Energy Challenge: A White Paper on Nuclear Power, January 2008), and so do not require an SEA assessment to be carried out in advance of their adoption or publication. This is for a number of reasons, the principal one being that the preparation of policy documentation is not specifically required by legislation or a mandatory administrative process. So how does an authority determine whether its proposed ‘plan or programme’ is subject to the requirements of the SEA Directive? The answer must lie, to a certain extent, in the SEA Directive itself, but particular consideration must also be given to what, in practice, the drafting of policy documents will lead to. Is the document one that is specifically required by legislation? Will it be used as a framework (or part of a framework) for subsequent development consent decisions? Are the issues it addresses ones that are likely to have significant environmental effects? If the plan or programme is to proceed on the basis of identifying development suitability on a site-specific basis, there will inevitably be greater pressure to ensure that SEA is undertaken.

Take the proposed United Kingdom Nuclear National Policy Statement (NPS) as an example; all of these criteria are clearly met. Having addition­ally resolved to invite the nomination of specific sites for assessment against a range of criteria relevant to the subsequent grant of a development consent for new nuclear power stations, the United Kingdom government has accepted it is inevitable that the SEA process must be adhered to. For the nuclear NPS, the UK Department of Energy and Climate Change/ Office for Nuclear Development (OND) has indicated that an ‘Assessment of Sustainability’ (AoS) will be undertaken that discharges all the require­ments of the SEA Regulations. For this Nuclear NPS, at least, the AoS may replace SEA (see ‘Towards a Nuclear National Policy Statement’, OND, January 2009). Although it is now undertaking that process at the same time as drafting the NPS, the UK government recognises that formal stages of SEA are such that the draft NPS and the formal SEA Environmental

Report cannot be one and the same thing, but have to be offset. The NPS must have been issued in draft before the Environmental Report under the SEA Regulations can be prepared.

So, in cases such as this, policy makers are faced with the challenge of ensuring that there is adequate environmental investigation of the policy that they intend to put forward before the policy is formalised. In this respect, the United Kingdom’s forthcoming Nuclear NPS is expected to set the standard for the level of information required for the drafting of an NPS that is site-specific.

The IAEA has provided a complete and satisfactory set of requirements and safety guides on NPP siting through its safety standards series. The safety requirements document (IAEA, 2003a) includes a list of general requirements, a list of specific site requirements for evaluating the effects of external events on the plant safety, and the potential effects of the plant on the site and its surroundings.

Today the nuclear industry avails of two valuable documents that can be used as a reference when writing up the technical requirements for a new nuclear plant: the European Utility Requirements (EUR) for LWR Nuclear Power Plants in Europe (EUR, 2004, accessed 2011), and the EPRI Utility Requirements Document (URD) for Next Generation Nuclear Plants in the United States (EPRI, 2011). These are briefly outlined below.

An NPP will cease to be operational if a decision is taken to retire it from service, at the end of its licensed operating life or earlier. Several causes may dictate the earlier termination of an operating NPP, for example a decision by the licensee for economic or other reasons, the cancellation of the operating license by the RB, or the impossibility of recovery from an accident. The licensee should formally communicate to the RB about such a decision and the proposed arrangements for safekeeping of the facility pending its decommissioning.

The RB will review the proposal and appropriately modify the operating license. This includes changes in the technical specifications for operation and other licensing conditions, like those related to requirements of operat­ing staff, in-service inspection, and surveillance and operability of equip­ment to maintain the facility in a safe state. However, as long as nuclear fuel is present in the reactor core, the NPP is considered operable and the complete operational discipline should remain in force. After the reactor core is completely defuelled, the operating license may be terminated. However, the facility will still remain under regulatory control, with appro­priate safety requirements specified, as long as radioactive material is present at the site, pending its final decommissioning.

Most RBs have enacted regulations on decommissioning commercial nuclear power plants, with these regulations covering the time from termi­nation of operation to when the site is declared fit for unrestricted use. In any case, the licensee declares that the reactor has been shut down perma­nently and that they are ready to request a decommissioning license. The licensee keeps its prime responsibility as long as there is fuel on the reactor premises, either in the reactor core or in the spent fuel decay pool. After removing the fuel, responsibility for the site can be transferred to the agency conducting the dismantling.

The operator performing the dismantling should submit a safety analysis report to the RB describing the decommissioning activities to be conducted and the safety provisions that have been made to comply with the existing regulations. Attention is given to decontamination activities, to radiological protection of workers and the environment, and to the management of radioactive waste. The RB evaluates the information received and prepares an SER with the proposed limits and conditions to be complied with during the process, these mostly being the acceptable residual radioactivity level remaining on the site for it to be released for unrestricted use, the reports to be submitted on the conduct of operations, and hold points for inspec­tion. At the end of the process, a radiological survey of the site is generally conducted before releasing and declaring that decommissioning has ended.