The NRC 10 CFR Part 100 titled Reactor Site Criteria, dated 1962, last amended in 1996, is divided into two subparts applicable to reactors built before 10 January 1997 and for site-related applications submitted on and after such date. The date separation is due to the creation of the new com­bined construction and operation licence (COL), while maintaining the previous system requiring separate construction and operation licences. In both cases a site permit is considered. Regarding population distribution the regulations require that every site must have an exclusion area and a low population zone and a population centre distance.

The exclusion area is formally defined as:

‘that area surrounding the reactor, in which the reactor licensee has the author­ity to determine all activities including exclusion or removal of personnel and property from the area. This area may be traversed by a highway, railroad, or waterway, provided these are not so close to the facility as to interfere with normal operations of the facility and provided appropriate and effective arrangements are made to control traffic on the highway, railroad, or waterway, in case of emergency, to protect the public health and safety.’

The low population zone is formally defined as:

‘the area immediately surrounding the exclusion area which contains residents, the total number and density of which are such that there is a reasonable prob­ability that appropriate protective measures could be taken in their behalf in the event of a serious accident.’

The population centre distance is defined as:

‘the distance from the reactor to the nearest boundary of a densely populated center containing more than about 25,000 residents.’

It is added that the population centre distance:

‘must be at least one and one-third times the distance from the reactor to the outer boundary of the low population zone.’

For currently operating reactors 10 CFR Part 100 makes reference to the TID-14844 document already mentioned (DiNunno et al., 1962) to deter­mine the values of the defined areas and distances. In the calculations the radioactive source term released to the atmosphere is based upon a major accident that would produce potential hazards ‘not exceeded by those from any accident considered credible’. It is assumed that the whole reactor core will melt, releasing 100% of the noble gases’ radionuclides and 25% of iodine radionuclides, in three different forms: 22.75% as elemental iodine; 1.25% as particulate iodine; and 1.0% as methyl iodide, a molecule observed in experiments with limited radiological importance. It is also supposed that the containment system will remain intact, releasing radioactive products at the containment’s expected demonstrable leak rate; it is also assumed that containment spray and pool pressure suppression systems will function as designed and the release will be dispersed under assumed meteorological conditions.

Under such circumstances are calculated the whole body dose and the dose to the thyroid from the inhalation of iodine isotopes received by the standard man, standing in the axis of the radioactive plume, as a function of the distance from the release point for the first two hours after the onset of the release and during the total release time. The radius of the exclusion area is the maximum distance at which the assumed person will receive during the first two hours a whole body dose of 25 rem (equivalent to 0.25 sievert in SI units) or a thyroid dose of 150 rem (equivalent to 1.5 sievert in SI units). The radius of the low population zone follows the same criteria, but the reference dose will be received during the whole release time. The methodology is illustrated in Fig. 18.2. For a LWR of 1 GW of standard

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Radius of low population zone

18.2 Demographic site parameters.

design the radius of the exclusion area varies from 750 m to 1200 m, the low population zone from 3 to 5 km and the distance to population centres from 4 to 7 km.

The guide clearly indicates that the reference doses must not be consid­ered as acceptable emergency doses to the public; they are only reference values for the purpose of defining the population distribution site param­eters. The 0.25 sievert value for the whole body dose corresponds numeri­cally with the once in a lifetime accidental or emergency dose for radiation workers which is generally disregarded in the person’s radiation status.

The demographic site parameters should not be taken as reference to emergency planning, which normally covers up to 30 km from the plant and could be further extended and adjusted to any real situation. The basis of the calculation assumes the total meltdown of the reactor fuel, but the containment function responded as foreseen in the design considerably reduces the source term and its composition. In the 1979 TMI-2 accident 20% of the core melted, but the containment and corresponding safety safeguards responded as expected and only a preventive limited evacuation was considered necessary. In the 1986 Chernobyl-4 accident the nuclear core, the core pressure containment and the conventional building were destroyed by the vapour and hydrogen explosions, the fuel was dispersed and melted in the open air, releasing radioactivity over 10 days, and a large number of people far from the plant were evacuated or permanently relo­cated. In the 2011 Fukushima-1 accident three nuclear units were affected whose cores partially melted, but the containment and related safeguards only partially complied with their functions, resulting in substantial releases to the atmosphere of noble gases and volatile iodine, tellurium and cesium radionuclides. A large amount of contaminated water was also released to the sea. At the time of this writing, people were evacuated up to 20 km from the plant and recommended to take shelter at up to 30 km, for long periods of time.

If financing is required by the owner for the project, the owner may decide to arrange it directly with the financing institutions, or he may wish to request the bidders to submit proposals for financing arrangements together with their bids for plant supply.

The owner may have developed plans to finance the whole, a substantial part or just a portion of the project (for example, the foreign components of the bidder’s scope of supply, including nuclear fuel). Whatever the plans and expectations of the owner regarding project financing, the BIS should clearly indicate whether financing is required to be provided or arranged for by the supplier.

The purpose of the FR document of the BIS is to specify:

• The scope and conditions of the financing required by the owner to be provided or arranged by the supplier

• The information that, as a minimum, shall be submitted by the bidder in his financing proposal to provide clear understanding of the financing conditions offered and facilitate the owner’s evaluation.

The financing institutions (lenders) with whom the bidder has arranged the requested financing scheme shall present a complete financing proposal including all the information requested by the owner; this document shall be submitted together with the plant supply proposal prepared by the bidder.

The FR document should request the bidder to describe, in his financing proposal, the financing instruments and approach that he intends to use (such as export credit financing, co-financing, multi-country financing, and supplier’s credit).

Export credit financing (buyer’s credit) is a common approach in the financing of nuclear projects. The following paragraphs indicate the typical information that the owner should request in the financing proposal in case this financing approach is selected.

Licensing of a country’s first NPP poses several challenges to the RB, as well as to the license applicant. This is mainly on account of a lack of experienced personnel who can clearly understand the safety aspects detailed in the PSAR and the FSAR and the various supporting technical documents. Other major difficulties will be the need for the licensing process to match the project schedule, and the non-availability of national safety standards.

These challenges can be met to a large extent through: (a) implementing a well-formulated human resources development plan; (b) using technical assistance from an experienced regulator (ER); (c) the use of the safety evaluation of a reference NPP that is similar in design to the NPP to be built, and which has already been licensed by a competent and experienced RB, usually one in the country of origin of the project; (d) adoption of international safety standards, mainly the ones developed by the IAEA and applied under its recommendation; and (e) development of a strategic plan for the conduct of the licensing process.

Many aspects of the national technical development to support an emerg­ing nuclear power programme that are described in Chapter 7 are also applicable to licensing activities, for both the license applicant and the RB. Aspects specific to the licensing of a country’s first NPP are covered below.

Over time, organisations will experience changes to personnel and perform­ance; if these changes go undetected they could have an adverse effect on nuclear safety and plant performance. Similarly, circumstances change and organisational needs will change as a result. It is important therefore that the effectiveness of organisations is regularly reviewed to ensure they are compliant with nuclear site licence conditions and company arrangements described in QA programmes and to identify areas for improvement.

The nuclear industry has developed many programmes for the evaluation of organisational effectiveness, some of which are described below.

5.1.6 Quality assurance audits

Typically, quality assurance audits determine whether organisations are compliant with company arrangements. Chapter 21 addresses QA in detail.

Some countries are carrying out national education initiatives to promote nuclear knowledge, such as the examples in the USA, the UK, Japan and France described below.

USA: NEUP (2009)

The US Department of Energy’s Office of Nuclear Energy (DOE) created Nuclear Energy University Programs (NEUP) in 2009 to consolidate its university support under one programme. NEUP funds nuclear energy research and equipment upgrades at US colleges and universities, and pro­vides scholarships and fellowships to students. DOE personnel in Washington DC oversee the programme and the Idaho-based NEUP Integration Office administers the awards. NEUP’s goals and objectives are to support out­standing, cutting-edge and innovative research at US universities by:

• Attracting the brightest students to the nuclear profession and support­ing the nation’s intellectual capital in nuclear engineering and relevant nuclear science, such as health physics, radiochemistry and applied nuclear physics

• Integrating research and development (R&D) at universities, national laboratories and industry to revitalize nuclear education

• Improving university and college infrastructures for conducting R&D and educating students

• Facilitating the transfer of knowledge from the aging nuclear workforce to the next generation of workers.

A large number of personnel trained in a variety of fields are required to support a nuclear power programme in the long term. An initial training programme is necessary to orient the newly inducted persons in nuclear science and technology where after they can receive advanced training. This initial training can be imparted through undergraduate nuclear engineering courses. However, after enrolment of students in such courses it would typi­cally take four to five years before they become available for deployment in the nuclear power programme. An alternative could be to design capsule courses of about one year’s duration where graduates or postgraduates in science and engineering could be taught nuclear subjects. Such courses are available in a few countries and arrangements may be made for getting personnel trained in these centres. However, subsequently it would be advantageous to establish such a course within the country to be able to train a larger number of personnel on a regular basis and at low cost. For personnel who are going to be engaged in the operation and maintenance (O&M) functions of the NPP, further on-the-job training should be arranged in an operating NPP or a research reactor such that they can be readily inducted into the detailed O&M training for the NPP to be constructed to become licensed operators at the earliest opportunity.

The costs of electricity generated by different sources should include the cost of the plant, the cost of the fuel, and the cost of operation and main­tenance (the economics of nuclear power are considered in detail in Chapter 15 of this book). The cost of the nuclear plant is the most relevant of the three component costs which, all considered, make nuclear power the cheapest producer of base load electricity (though only if discount rates are reasonable and the plant can be put into operation as designed). Long delays caused by licensing requirements, equipment supplies or other causes can change that situation, this being the reason why utilities insist on reli­able licensing processes and government guarantees.

Prices (quoted here in US dollars per kilowatt of electric power) vary considerably. The cost of plants built recently in Japan and South Korea has been quoted as close to $3000 per kW, while the Olkiluoto and Flamanville plants under construction in Finland and France, respectively, may cost more because of delays in construction.

Many national and international institutions constantly estimate the costs of electricity from various sources. The NEA/OECD, in cooperation with the International Energy Agency, estimates costs on a regular basis and provides updates (OECD, 2011). Likewise, industry institutions such as the World Nuclear Association (WNA) also provide updates on nuclear power plant economics (WNA, 2011). In all cases, electricity costs from nuclear power are comparable with those from coal, and are cheaper than those for gas and renewable sources. When a carbon tax is imposed on coal and gas, nuclear power becomes the most competitive source.

The Integrated Modular Water Reactor (IMR) is a medium-sized power reactor with a reference output of 350 MWe and an integral primary system reactor with potential deployment after 2020 developed by Mitsubishi Heavy Industries in Japan. IMR employs the hybrid heat transport system, which is a natural circulation system under bubbly flow condition for primary heat transportation, and no penetrations in the primary cooling system by adopting the in-vessel control rod drive mechanism. These design features allow the elimination of the emergency core cooling system. Because of its modular characteristics, it is suitable for large-scale power stations consisting of several modules and also suitable for small power stations, especially when the capacity of the grid is small. IMR also has the capability for district heating, seawater desalination, process steam produc­tion, and so forth.

Referring back to Fig. 10.1, the operating company may be considered either to be at the centre of the action or to be surrounded on all sides. The one indisputable fact is that the operating company is in the nuclear energy business for the long run. Since the station is already committed and running, the capital is spent and a favourable return on investment can be obtained only by operating the plant for a number of years, the operating company has no way out but straight ahead. The key element for success of the enterprise is for the operating company to earn the confidence of the people in their ability to run the plant safely and efficiently.

So-called significant event reports are filed for each off-normal situation encountered during operation. These reports are filed in two different forms; the first identifies all staff involved in the event and their role in either initiating or mitigating the abnormality being reported. This report is used only by plant management for performance reporting and, if neces­sary, for retraining or discipline of individual staff members. The second form of a significant event report is distributed to regulatory staff, other operating plants, and design groups to serve as a detailed record of abnor­mal events that may provide lessons for improvement of future operating procedures. Abnormal event reports are distributed widely in order to maximize the benefits of the specific learning experience as well as contrib­uting to nuclear station operating experience in general. These events are analyzed by operations support groups around the world, and appropriate actions are taken. A condensed version of the events deemed to be most important to the broader community is forwarded to the IAEA incident reporting system (INIS) as well as to other international organizations.