In the absence of a high level of technical competence and sufficient operat­ing experience, it is not feasible to develop a full set of national safety standards for an NPP before the licensing process gets started. Safety stan­dards relevant to siting of the NPP and to general safety criteria may be nationally developed from IAEA models and made appropriate to the national conditions and requirements. Other more technological standards, like those of the IAEA and of the NPP vendor’s country, could be appro­priately used during the detailed design safety review process. However, the safety standards required for commissioning and then for operation of the NPP should be developed before commissioning work starts. This can be done based on the knowledge of the NPP design acquired from the design safety review and with appropriate technical assistance from the ER.

The full set of national safety standards could be developed after gaining a few years of operating experience when the national experts would have also acquired a good level of technical competence.

Over time, organisations and the individuals in them can change in both composition and performance just as the condition and performance of plant and equipment changes as a result of in-service aging. Engineers will be familiar with plant aging issues and the maintenance practices that seek to reverse or halt the impact of in-service degradation.

The same imperatives apply to organisations and the individuals in them. It is important, therefore, that the effectiveness of organisations and the individuals in them is carefully monitored and evaluated as described earlier. This is akin to condition monitoring of plant and equipment.

Interventions to maintain organisational effectiveness can come in the form of continuous training, which is analogous to preventative mainte­nance, or remedial training, which is analogous to equipment repairs.

5.1.8 Knowledge management and succession planning

Nuclear power plants are designed to last for several decades and genera­tions in the workforce. This poses two main challenges for the operating organisation. Firstly, it must have in place the means to identify the need for replacement in a timely manner. This is vitally important because of the long lead times involved in training and developing specialist personnel such as reactor operators, for example. Secondly, operating organisations must ensure that the knowledge and experience acquired by the personnel leaving the organisation is not lost with their departure. These two impera­tives give rise to the need for robust succession planning and knowledge management programmes.

The IAEA has recognised that knowledge management in the nuclear industry represents an international challenge to safe operation and decom­missioning of nuclear facilities. They define the challenge and their commit­ment to addressing it in the following way:

‘There is clear consensus that nuclear knowledge is a strategic asset, which needs to be preserved regardless of national policies related to the utilization of nuclear power. Nuclear knowledge is needed for safe operation of nuclear facilities until they are closed down and further for their safe decommissioning and disposing of waste.

Alongside other developments, the changing nuclear workforce is raising issues of “knowledge management” underlying the safe and economic use of nuclear science and technology. In recent years the nuclear workforce has been aging, that is, more and more nuclear workers are approaching retirement age, without a corresponding influx of appropriately qualified younger personnel to replace them.

The complexity and magnitude of the problem needs a systematic approach to locate and represent the knowledge domains and to perform a critical evalu­ation of knowledge values.

In recognition of these and other trends, the IAEA executive bodies have called for measures to better identify the nature and scope of the problem, to understand what Member States are doing to address it, and to determine what co-operative international actions might be appropriate to enhance succession planning.

Knowledge and in particular nuclear safety knowledge is created and shared in the frame of the Agency’s Nuclear Safety activities. The IAEA is pursuing a vigorous knowledge management programme to ensure that existing knowl­edge is fully utilized by the current generation of nuclear professionals and is effectively transferred to the work force of the future.

Focus is on knowledge generation, codification, mapping, retention and transfer. Central to the KM activities is the establishment of an environment conductive to sharing knowledge including tacit knowledge.’

Utility technical training programmes which use the SAT infrastructure devised and employed in the US are very powerful programmes for the identification of knowledge and experience required in nuclear power plants and for institutionalising it in training programmes in which it becomes sustainable.

A viable nuclear knowledge culture needs constant attention throughout the different stages of the nuclear lifecycle, which implies nuclear knowl­edge management.

Adequate numbers of competent and motivated personnel must be avail­able during any phase of a nuclear programme. From the regulatory per­spective, the licensing requirements define that the licensee needs to be able to demonstrate that adequate numbers of competent personnel are avail­able, until the facility is finally removed from regulatory control.

The knowledge and skills necessary to purchase, construct, license, operate, maintain and comply with regulations of a nuclear power plant are spread across most scientific and engineering disciplines. Specific considera­tions for the nuclear industry include:

• Additional knowledge and appreciation of the increased attention to detail in order to ensure operational safety, security and radiation pro­tection are vital and require a heightened attention to the quality of major systems and equipment.

• Expertise in nuclear physics and nuclear materials science for reactor operation and fuel cycle management.

• Finally, along with the technical skills, there must be a strong commit­ment to safety culture, which instils personal responsibility for the safety of all individuals involved in the programme.

While screening criteria available internationally can be made use of for deciding on the NPP site from amongst the candidate locations, there will be several local considerations such as land use and water use around the site, the proximity of the site to heritage buildings or archeological monu­ments, and the likely extent of displacement of local population and its social consequences that need to be taken into account. Apart from screen­ing criteria there are several desirable criteria such as ready availability of access roads to the site, infrastructure available nearby to facilitate con­struction and the existence of sea port and railhead nearby for transporta­tion of heavy and large components to the site. For these reasons it is essential that strong national participation be ensured in the selection of the site for the NPP.

A nation developing nuclear power or simply building a new power station benefits from improved energy independence from the outside world, with upgrading of the reliability and security of electrical production, and pro­motion of the educational, scientific and technical development of the country.

Countries appreciate being energy independent from other countries. Energy independence means supply security and price stability. Countries which are dependent on energy from external suppliers cannot control their economies and can be the subject of energy embargoes — circumstances which have occurred frequently, historically. The energy policies of most countries strive to maintain their independence from other countries as much as possible. Energy independence should not be confused with inter­dependence, i. e. mutual dependence, which favours trade and interchange among the parties.

Energy independence is achieved by substituting fossil fuels with domes­tic products, such as developing nuclear power that directly replaces fossil fuels for the generation of electricity. In fact, energy independence is a major driver for nuclear power. The UK government was not interested in new nuclear builds until it realized that its gas and oil reserves in the North Sea had been exhausted and that it had to import such commodities. Many European countries are heavily dependent for energy on Russian gas and on oil from the Gulf and North African countries, and their energy situation is vulnerable. Because of nuclear phobia (very intense in some central European countries) and the risks associated with climate change produced by CO2 emissions, the current policy of the European Union is to develop wind and solar power, probably beyond their technical and economic pos­sibilities. Such developments are only possible if they are heavily subsidized, which has a negative impact on economic development.

Replacing fossil fuel by nuclear energy does not necessarily make coun­tries completely energy independent, but certainly improves the situation. The approximate specific energy delivered by natural gas is 55 MJ/kg and half that amount for hard coal, while low enriched uranium in current LWRs can produce some 3.9 x 106 MJ/kg. This considerably simplifies fuel transportation and storage issues. Moreover, uranium resources are more evenly distributed than gas and oil; reserves are abundant and the volatility of prices more limited. Apart from that, the cost of the fuel cycle represents only some 15% of the generated electricity cost, from which only 5% cor­responds to the price of the natural uranium.

To assess the benefits obtained from gaining energy independence by selecting nuclear power, the volatility of fossil fuel prices and the stability of nuclear fuel pricing have to be compared, as well as the cost of storing such fuels to control supplies and the impact of fuel on the production cost of the electricity generated.

The 15 millennia of accumulated operating experience of the world’s nuclear power plants has proved that, on average, they can now operate reliably within load factors close to 90%. Some plants have refuelling outages every one to two years, lasting three to six weeks, and generally operate continuously at nominal power in between outages. Although they can change power, these plants are designed to provide load-based electricity and are not suitable for following demand. In this sense, they cannot provide backup power for intermittent sources, such as solar and wind, but can be good substitutes for large coal and gas power stations.

The net benefits provided by this characteristic are country dependent. A nuclear power plant which is part of a national electricity grid can provide stability to the grid whilst, for safety and operational reasons, the nuclear plant itself requires the grid to be stable at the same time. It is essential that there is an equilibrium between generation and demand; when this equilib­rium is lost, the grid becomes unstable and there could be limited or even complete blackouts. To avoid such situations, generating plants have to be able to provide primary regulation (within seconds) for small fluctuations, secondary regulation (within minutes) for larger perturbations, and also tertiary regulation (within hours) to fully recuperate any perturbed equi­librium. Nuclear power plants have the capability of reliably maintaining power and responding to small fluctuations but they are not normally used for secondary regulation.

NuScale is a reactor design based on a concept originally proposed by Oregon State University in the USA. A NuScale plant can consists of one to 12 independent modules, each capable of producing a net electric power of 45 MWe. Each module includes a Pressurized Light Water Reactor oper­ated under natural circulation primary flow conditions. Each reactor is housed within its own high-pressure containment vessel which is submerged underwater in a stainless steel-lined concrete pool. In early 2008, NuScale Power notified the US Nuclear Regulatory Commission of its intent to begin pre-application discussions aimed at submitting an application for design certification of a 12-module NuScale power plant.

One of the most important conclusions in the INSAG-12 report (INSAG, 1999a) is the upper frequency target of 10-4 or less per year for severe core damage. This principle is discussed under the heading 2.3 Technical Safety Objective, paragraphs 19 to 27, in the INSAG-12 document. The objective of this approach is to establish an upper bound recurrence frequency of severe core damage accidents that could lead to release of a large amount of radioactive material that could, if the containment structure were damaged consequent to the event, lead to severe consequences for human health.

The INPO organization was formed in 1979 in the wake of the Three Mile Island nuclear plant accident. A number of US industry leaders recognized that the industry must do a better job of policing itself to ensure that an event of this magnitude should never happen again. INPO was formed to establish standards of excellence against which the plants are measured. An inspection of each member plant is typically performed every 18-24 months. The Institute’s programs include:

• SEE-IN (an information sharing network)

• EPIX (an equipment failure database)

• National Academy for Nuclear Training

• Events analysis

• Human performance

• Accreditation

• Evaluations.

Information regarding INPO as well as the Nuclear Energy Institute, the International Atomic Energy Agency, and the World Association of Nuclear Operators can be found at WANO (2010).

The primary means of preventing and mitigating the consequences of acci­dents is the ‘defence in depth’ concept (IAEA, 1996a). Defence in depth is implemented primarily through the combination of a number of consecu­tive and independent levels of protection that would have to fail before harmful effects could be caused to people and to the environment. Defence in depth is provided by an appropriate combination of an effective manage­ment system with a strong management commitment to safety and a strong safety culture; adequate site selection and the incorporation of good design and engineering features providing safety margins, diversity and redun­dancy; and comprehensive operational procedures and practices as well as accident management procedures.

Accordingly to the defence in depth concept, the design, construction and operation of nuclear facilities are conducted under the most stringent quality controls to comply with safety principles, including the development of the necessary provisions to deal with emergency situations in all modes of operation. The owner and the national authorities in charge of nuclear safety perform independent verification programmes to ensure strict com­pliance with safety and quality requirements.

Despite the fact that the nuclear facilities and their safety systems are designed, installed, tested, operated and verified in accordance with the strictest safety and quality standards, the possibility of an accident, a human error or an intentional action that can seriously damage the facility cannot be excluded, although its probability can be considered as extremely low. In very unlikely circumstances, these situations could cause simultaneous failure of operating and safety systems, which could produce radiation exposure of facility workers or uncontrolled discharge of radioactive mate­rial to the environment. Furthermore, in very extreme circumstances, some external phenomena, e. g. earthquake, tsunami or sabotage, could severely damage the plant, its external and internal supplies of electric power or cooling water in such a way that the operator is unable to control the safety systems. This is the situation that occurred in the Fukushima nuclear power plant on 11 March 2011 as a consequence of a big earthquake and a tsunami that partially destroyed the facility.

Both circumstances could result in damage to the health of individuals living or working near the facility as well as to their property and to the environment.

The issue of proliferation extends beyond the NPT and the corresponding NNWS’s obligation to accept safeguards on all source or special fissionable material and to undertake a comprehensive safeguards agreement with the IAEA. As this book is focused on infrastructure and methodologies for the justification of nuclear power programmes, the three milestones36 described in the Milestones publication (IAEA, 2007a) are the focus of the detailed discussion on non-proliferation in this subsection. The information is orga­nized by the essential obligation/commitment undertaken by a NNWS Party to the NPT, with associated safeguards requirements linked to the relevant milestone(s) in IAEA (2007a).

In generic terms, prior to reaching Milestone 1, the State is normally working to acquire a comprehensive understanding of the requisite obliga­tions and commitments involved. Once a decision to proceed with the infrastructure development is made, the State organizes the national means and plans needed to successfully implement the decision while progressing towards Milestones 2 and 3. As a State advances with its nuclear energy plans, it would be beneficial for the State to periodically perform a self­assessment, keeping in mind some example metrics presented in Table 13.1.

36 Milestone 1 is defined as when the State is ready to make a knowledgeable com­mitment to a nuclear power programme as it pertains to each of 19 issues, one of which is safeguards; Milestone 2 is defined as when a State is ready to invite bids for the first nuclear power plant; Milestone 3 is defined as when a State is ready to commission and operate its first nuclear power plant.