Definition

Activation

This term refers to the process of creating a radioisotope. This is achieved when a stable element is bombarded with either neutrons or protons.

Activity

The rate at which radioactive material disintegrates or decays per unit time. The units can be measured as either a curie (Ci) or a Becquerel (Bq).

AGR

Advanced Gas Cooled Reactor - A term used for the second generation of British Power Reactors, now operated by British Energy. The fuel used in the reactor is slightly enriched uranium oxide clad in stainless steel. The coolant is carbon dioxide and the moderator is graphite. The fuel is manufactured by Westinghouse Ltd at Springfields and reprocessed in THORP.

ALARP

An HSE concept - As Low as Reasonably Practicable: A term used in the analysis of safety-critical and high-integrity systems. The ALARP principle is that the residual risk shall be as low as reasonably practicable, forms part of a Nuclear Safety Justification and is derived from legal requirements in the Health & Safety at Work Act 1974 and is explicitly defined in the  Ionising Radiation Regulations 1999.

AP1000

A nuclear reactor designed by Westinghouse currently being reviewed by the HSE and the EA for new nuclear build within England and Wales. This design differs from the EPR reactor design of Areva in that this reactor is made up of a series of modules than can be constructed off-site for transport and fitting on-site.

Areva

The designer/manufacturer of the EPR nuclear reactor, one of the two designs included within the GDA. With manufacturing facilities in 43 countries and a sales network in more than 100, AREVA offers customers technological solutions for CO2-free power generation and electricity transmission and distribution.

Atom

The atom is the smallest particle of an element. It consists of a central core, or nucleus, that is made up of protons and neutrons. Electrons revolve in orbits around the nucleus. 

Atomic energy

This term refers to the energy that is released in nuclear reactions. There are two chief ways this can occur. The first in nuclear fission, whereby a neutron will initiate the breaking up of an atom's nucleus into smaller pieces. The second is nuclear fusion, whereby two nuclei are joined together under intense heat. It is more correctly called nuclear energy.

Background radiation

This is radiation which comes from cosmic sources. Typical examples of which include; naturally occurring radioactive materials (e.g. radon) and global fallout which exists in our environment as a result of nuclear weapon testing. Radiation which comes from source, byproduct, or special nuclear materials regulated by the Nuclear Regulatory Commission would not come under this definition. The typically quoted average individual exposure from background radiation is 360 millirems per year.

BAT

A regulator test - Best Available Techniques: A term used in reactor design specifications, waste handling and decommissioning and other health and safety led environments.

BE

British Energy PLC. BE is the UK’s largest electricity generator. It is the current Site Licensee for the AGR & PWR second-generation power stations in the United Kingdom. The stations currently operated by BE are: Hunterston B, Torness, Heysham 1 and 2, Hartlepool, Hinkley Point B, Sizewell B, and Dungeness B. BE is now a wholly owned subsidiary of EDF.

Becquerel (Bq)

The unit of radioactive decay equal to 1 disintegration per second. 37 billion (3.7 x 10¹⁰) becquerels = 1 curie (Ci). The becquerel is named for Henri Becquerel, who shared a Nobel Prize with Pierre and Marie Curie for their work in discovering radioactivity.

Biological Shield

This is a mass of absorbing material which is placed around a reactor or radioactive source  in order to reduce the radiation to a level safe for humans.

BNFL

British Nuclear Fuels plc - Formerly the holding company for British Nuclear Group and Nexia Solutions.

BOCI

Balance of conventional island - all components, equipment and systems included in the conventional island scope, with the exception of the turbine generator plant

Boiling Water Reactor (BWR)

A reactor design where water is allowed to boil in the core. The resulting steam is used to drive a turbine and electrical generator, thereby producing electricity.

BONI

Balance of nuclear island - all components, equipment and systems included in the nuclear island scope, with the exception of the nuclear steam supply system (NSSS). 

BPEO

Best Practicable Environmental Option - a set of procedures adopted by Great Britain with the goal of managing waste and other environmental concerns. According to the Royal Commission on Environmental Pollution, BPEO "emphasises the protection and conservation of the environment across land, air and water. The BPEO procedure establishes for a given set of objectives, the option that provides the most benefits or the least damage to the environment, as a whole, at acceptable cost, in the long term as well as in the short term."

CANDU

CANDU Reactor: A Canadian-invented, pressurized heavy water reactor developed initially in the late 1950s and 1960s. The acronym "CANDU", a registered trademark of Atomic Energy of Canada Limited, stands for "CANada Deuterium Uranium". This is a reference to its deuterium-oxide (heavy water) moderator and its use of uranium fuel (originally, natural uranium). All current power reactors in Canada are of the CANDU type.

Canister (waste)

A vessel for waste for handling, transport, storage and/or disposal. It is part of the waste container and the waste package. An example would be molten glass poured onto high level waste glass and in a specially designed canister, to cool and solidify. Container usually refers to high level waste.

Carbon Floor Price

The minimum value at which carbon can be traded.  The setting of a carbon floor price is essentially a regulatory/taxation policy which obliges polluters to pay at least a minimum value for the right to pollute.

Care and maintenance 

A stage in the process of decommissioning a nuclear site. It begins when the only significant buildings left on a site are the reactor buildings and an ILW store – these will be removed at the dismantling stage.

CCGT

Combined Cycle Gas Turbine:  In combined cycle gas turbine plant, a gas turbine generator generates electricity and the waste heat is used to make steam to generate additional electricity via a steam turbine; this last step enhances the efficiency of electricity generation. In a thermal power plant, high-temperature heat as input to the power plant, usually from burning of fuel, is converted to electricity as one of the outputs and low-temperature heat as another output.

CI

Conventional island - that part of an NPP that does not form part of the nuclear island. 

Clean-up

A term used in conjunction with decommissioning. Once a nuclear facility has been decommissioned the site needs to be cleaned-up to remove any possible contamination. The site is then returned (after consultation with the local community) to either a greenfield or brownfield site.

Contamination

The presence of undesired radioactive material that is deposited on the surface of or inside structures, areas, objects, or people.

Controlling mind 

The NDA works with its contractors and the Regulators in such a way that, having agreed with its contractors what can be done and by when, the NDA then don’t dictate how things will be done with regard to HSE related activities. This dictatorship is referred to as the ‘controlling mind’ principle. 

CORE

Cumbrians Opposed to Radioactive Environment: Started in 1980 as the Barrow Action Group to oppose the import of foreign fuel through the port of Barrow-in-Furness for reprocessing at Sellafield. Since then CORE has widened its campaign remit to cover all aspects of Sellafield's operations including the radioactive sea and air discharges, the resultant contamination of the local environment, and the health detriment to local communities and wildlife. Its core mission is to stop reprocessing, stop foreign imports, stop aerial and sea discharges, expose health damage and prevent Cumbria becoming the nuclear dustbin of the World.

Core

The central heat-producing part of a nuclear reactor which contains the fuel assemblies.

CoRWM

CoRWM – Committee on Radioactive Waste Management - is an independent committee appointed by the UK Government. Their original task was to review the options for managing those higher-activity UK radioactive wastes for which there is no agreed long-term solution. Their findings were published in July 2006, to which Government responded in October 2006, resulting in the incorporation of Nirex into the NDA.

CRC Energy Efficiency Scheme

The CRC Energy Efficiency Scheme (formerly known as the Carbon Reduction Commitment) is the UK's mandatory climate change and energy saving scheme. The scheme started in April 2010 and is administered by the Environment Agency. The scheme is central to the UK’s strategy for improving energy efficiency and reducing carbon dioxide (CO2) emissions, as set out in the Climate Change Act 2008. It has been designed to raise awareness in large organisations, especially at senior level, and encourage changes in behaviour and infrastructure.

Culham

The Culham Centre for Fusion Energy (CCFE) is the UK's national fusion research laboratory (formerly UKAEA Culham). Owned and operated by the United Kingdom Atomic Energy Authority.

DECC

Department for Energy and Climate Change: This is the Government Department that sponsors the NDA. DECC (together with its OND in relation to new nuclear) is responsible for all aspects of UK energy policy, and for tackling global climate change. DECC is working to ensure that the UK continues to enjoy a diverse and low-carbon energy mix, delivered through a market framework to ensure competitive prices.

The current Secretary of State is Chris Huhne MP.

Decommissioning

1. The final phase in the life cycle of a nuclear installation covering all activities from shutdown and removal of fissile material to environmental restoration of the site through to its agreed End State.

2. The process of closing down a facility followed by reducing residual radioactivity to a level that permits the release of the property for unrestricted use.

Decontamination

The reduction or removal of undesired radioactive material from any structure, area, object, or person. Decontamination may be accomplished by:

(1) treating the surface to remove or decrease the contamination, (2) letting the material stand so that the radioactivity is decreased as a result of natural radioactive decay, or (3) covering the contamination to shield or attenuate the radiation emitted.

Deep Geological Repository

A nuclear waste repository excavated below 300 m within a salt dome or bedrock. It entails a combination of waste form, waste package and engineered seals that is designed to provide a high level of long-term storage without future maintenance.

DEFRA

Department for Environment, Food and Rural Affairs. DEFRA leads the Government’s view on the radioactive waste issue in the UK.

The current Secretary of State is Caroline Spelman MP.

Designate

The process by which the Secretary of State directs that NDA will have certain responsibilities to secure in relation to an installation, site or facility under the Energy Act 2004 through the issuing of a designating direction.  The Secretary of State  must lay a copy of every direction containing a designation before Parliament.

Disposal

In the context of solid waste, disposal is the emplacement of waste in a suitable facility without intent to retrieve it at a later date. Retrieval may be possible but, if intended, the appropriate term is storage. Disposal may also refer to the release of airborne or liquid waste to the environment (i.e. emissions and discharges).

Drigg

Former name - Low Level Waste Repository.

DRS

Direct Rail Services Limited: A wholly-owned subsidiary of the NDA, which provides rail transport services for nuclear materials (and other commercial rail freight operations) in the UK.

DSRL

Dounreay Site Restoration Limited: The site licence company at the Dounreay site in the far north of Scotland. The staff were all formerly part of UKAEA but a new company was established and became the SLC on 2 February 2009 as a precursor to competing the role of PBO.

EA

Environment Agency: The EA’s role is the enforcement of specified laws and regulations aimed at protecting the environment, in the context of sustainable development predominantly by authorising and controlling radioactive discharges and waste disposals to air, water (surface water, ground water) and land.

In addition to authorisation issued under the Radioactive Substances Act 1993, the EA also regulates nuclear sites under the Pollution Prevention and Control Regulations and issues consents for non-radioactive discharges. The equivalent body in Scotland is the Scottish Environment Protection Agency (SEPA).

EDF

Electricité de France. EDF have 58 reactors on 19 sites. The first reactors, built between 1958 and 1966, featured GCR (Graphite-Moderated Gas-Cooled Reactor) technology and are now being decommissioned. EDF is also now the owner of British Energy and its fleet of AGR and one PWR reactors in the UK. EDf is currently committed to a programme of nuclear power generating new build in the UK – it has stated that Hinkley Point C in Somerset will be the first proposed development for a new nuclear power station, followed by Sizewell C in Suffolk.

EIA

Environmental Impact Assessment.

End State

The state and condition in which the site of a former designated nuclear power station or facility must be restored to at the completion of the NDA's decommissioning work. This end state is consulted upon and agreed with the local community and key stakeholders.

Energy Act 2004 

(Energy Act 2008 now in place)

The NDA came into existence in July 2004 when the Energy Act received Royal Assent. The Act was introduced to give the NDA its legal status and the power to fulfil its responsibilities. 

Entomb

This is a method of decommissioning whereby the radioactive material is encased in a structurally long-lived material, such as concrete. The entombment structure is appropriately maintained and continued surveillance is carried out until the radioactivity decays to a level permitting decommissioning and ultimate unrestricted release of the property.

EPC Contract

EPC Contract – stands for "engineer, procure and construct" and is a term used both domestically and internationally to describe a contract under which an engineering contractor undertakes to: (1) design process plant (e.g. a petrochemical plant) or power plant (e.g. a turbine generator and ancillary plant, structures and infrastructure) or works with an heavy engineering element, usually to meet a specified level of performance, (2) procure all components comprised in the design as well as (3) physically construct and test the plant.  The equivalent term used in relation to more standard construction (e.g. housing, office blocks etc) is "design-and-build".

EPR

Evolutionary Pressurised Reactor or European Pressurised Reactor: A reactor designed by Areva, the first of which is being constructed at Olkiluoto in Finland. Full details of the reactor and its design can be found at www.epr-reactor.co.uk.

ESBWR

Economic Simplified Boiling Water Reactor: The latest evolution of General Electric’s Boiling Water Reactor (BWR) design, using passive circulation for normal operations and simplified, passive safety systems. This design simplicity greatly improves the overall safety of the plant, provides more location options, yields excellent economics and operational flexibility.

EU ETS

Formerly referred to as the EU Emissions Trading Scheme, the EU Emissions Trading System is one of the key policies introduced by the European Union (EU) to help meet its greenhouse gas emissions target of 8 percent below 1990 levels under the Kyoto Protocol. It is a Europe-wide cap and trade scheme that started in 2005 and is the first of its kind. Each EU member state must develop a National Allocation Plan approved by the European Commission which sets an overall cap on the total emissions allowed from all the installations covered by the System. This is then converted into allowances (1 allowance equals 1 tonne of CO2) which are distributed by EU member states to installations covered by the System. At the end of each year, installations are required to surrender allowances to account for their actual emissions. Installations can emit more than their allocation by buying allowances from the market or can sell surplus allowances to the market.

EURATOM

The European Atomic Energy Community (EAEC) or EURATOM Within the European Union, nuclear matters are the subject of a separate treaty dating from 1957 which established EURATOM also known as EAEC to encourage progress in the field of nuclear energy.

Exposure

Being exposed either to ionising radiation or radioactive material.

FDP

The Funded Decommissioning Programme. Any operator of a new nuclear power station must have an FDP, approved by the Secretary of State, in place before construction of a new nuclear power station begins and must comply with this programme thereafter. This will include a commitment to pay into a secure and independently managed fund to cover all the costs of decommissioning, clean up and disposing of the waste.

Feed in Tariff (FIT)

A means for governments to set above-market rates for electricity generated from renewable sources. By obliging electricity utility companies to buy renewable electricity at a fixed price for a fixed number of years, renewable installations become cost effective for the installer. A feed in tariff is effectively a subsidy designed to increase the exploitation of renewable energy sources, and to help governments to meet their carbon reduction obligations.

Fission

Fission creates the release of energy where a nucleus splits into at least two other nuclei. Two or three neutrons are usually released during this type of transformation.

Flamanville 3

EDF/Areva EPR new build project underway in France.

Flask (nuclear – transport)

A container used to transport waste nuclear materials for example between nuclear sites within the UK

Fuel cycle

The sequence of steps involved in supplying, using, and disposing of the fuel used in nuclear reactors.

Fuel reprocessing

The method of processing reactor fuel in order to separate the unused fissionable material from waste material.

Fusion

Thermonuclear fusion. A process in which two or more light nuclei are formed into a heavier nucleus and energy is released.

Gas-cooled reactor

A nuclear reactor where gas is used as a coolant.

GDA

Generic Design Assessment: The assessment by the Health and Safety Executive and the Environment Agency to ensure that any new nuclear power stations built in the UK meet the highest standards of safety, security, environmental protection and waste management. They are currently assessing two new nuclear power station designs:

• The UK-EPR designed by Areva and EDF, and
• The AP1000 designed by Westinghouse.

GDF

Geological Disposal Facility

Graphite 

The NDA is currently exploring the management/treatment options for graphite waste, taking account of worldwide developments and best practice. Finding an innovative solution to graphite wastes would inform a business case for accelerated decommissioning at Magnox reactor sites. 

Green Energy Certificate

Generators of electricity from renewable sources may be entitled to claim three types of Green Energy Certificate. The three types of certificate are: Renewables Obligation Certificates (ROCs), Levy Exemption Certificates (LECs) and Renewable Energy Guarantees of Origin (REGOs).

HALEF

Highly Active Liquid Effluent Facility.  The HALEF is made of seismically qualified reinforced concrete and comprises a series of storage tanks used to store radioactive waste arising from nuclear processing operations.

Health Physics

A field of science concerned with radiation physics and radiation biology with the goal of informing the safe use of ionising radiation. Health physicists principally work at facilities where radionuclides or ionising radiation are used or produced.

Heavy water

Water containing significantly more than the natural proportions (one in 6,500) of heavy hydrogen (deuterium, D) atoms to ordinary hydrogen atoms. Heavy water , which is effective in slowing neutrons down and also has a low probability of absorbing neutrons, is used as a moderator in some reactor designs.

HEU

Highly Enriched Uranium - Uranium that has been modified by increasing the concentration of the fissionable isotope U-235

Uranium containing 20% or more of the isotope uranium-235. A quantity of HEU can be described in terms of either the total mass of all the uranium isotopes, kg U, or as the mass of the fissile isotope uranium-235, kg U 235. For example, 100kg U of 70% enriched HEU could also be described as 70kg U 235.

High Level Waste

High-level radioactive wastes are the highly radioactive materials produced as a byproduct of the reactions that occur inside nuclear reactors.

High-level wastes take one of two forms:

• Spent (used) reactor fuel when it is accepted for disposal
• Waste materials remaining after spent fuel is reprocessed

Spent nuclear fuel is used fuel from a reactor that is no longer efficient in creating electricity, because its fission process has slowed. Spent fuel and high-level waste contain highly radioactive fission products, which need to be carefully protected as they decay over many years.

HLW 

High-Level Waste: Heat-generating waste that has accumulated since the early 1950s at Sellafield and Dounreay, primarily from the reprocessing of spent nuclear fuel. The temperature in HLW may rise significantly, this factor has to be taken into account when designing storage or disposal facilities. 

Horizon Nuclear Power

A UK energy company (a joint venture between E.ON UK and RWE npower) which is committed to developing a new generation of nuclear power stations. The company aims to deliver around 6,000 MW of new nuclear power station capacity in the UK by 2025. This programme is likely to involve more than £15bn of investment, and is likely to focus on sites at Wylfa (Isle of Anglesey) and Oldbury in Gloucestershire.

HSE 

Health and Safety Executive: A statutory body whose role is the enforcement of work-related health and safety law under the general direction of the Health and Safety Commission established by the Health and Safety at Work Act 1974. HSE is the licensing authority for nuclear installations. The Nuclear Safety Directorate of the HSE exercises this delegated authority through the Nuclear Installations Inspectorate who are responsible for regulating the nuclear, radiological and industrial safety of nuclear installations UK-wide.

IAEA

International Atomic Energy Agency: The Vienna-based IAEA (part of the United Nations) is the global focal point for nuclear co-operation and promotes the peaceful use of atomic energy. It gives guidance on nuclear safety and verifies that members comply with their safeguard obligations and use nuclear material only for peaceful purposes.

ILW

Intermediate Level Waste: Waste with radioactivity levels exceeding the upper boundaries for Low Level Waste (LLW), but which do not need heating to be taken into account in the design of storage or disposal facilities. ILW arises mainly from the reprocessing of spent fuel, and from general operations and maintenance of radioactive plant. The major components of ILW are metals and organic materials, with smaller quantities of cement, graphite, glass and ceramics.

INS 

International Nuclear Services Limited: A wholly owned subsidiary of the NDA. INS was formerly known as Spent Fuel Services, an operating unit within British Nuclear Group. Its main focus continues to be the customer interface to over 20 utility customers for reprocessing and MOX fuel supply contracts and the associated transportation of these products. 

IPC

Infrastructure Planning Commission: the independent body established under the Planning Act 2008 that decides applications for Nationally Significant Infrastructure Projects (i.e. projects above certain thresholds) such as new nuclear power but also includes power stations (including offshore wind farms), gas storage facilities, energy transmission systems, energy from waste projects, road, port, airport, reservoirs and major waste water treatment plants and water transfer schemes.

Applications are made to the IPC for a Development Consent Order ("DCO") which replaces the old regime of applications for Section 36 Consents under the Electricity Act 1989 (although this remains for applications which fall outside of the IPC regime).  DCOs bring together a number of different planning and consent regimes including planning permission, compulsory purchase powers, the diversion or stopping up of rights of way and FEPA & CPA Licences (soon to be replaced with Marine Licence).

The individual scheme promoter engages in significant community and stakeholder consultation before making its formal application to the IPC.

The IPC will decide whether or not to grant development consent in accordance with relevant National Policy Statements (NPSs).

The IPC determines the proposal after a process involving submissions from interested parties and open hearings when the public could have their say. IPC decisions are open to legal challenge.

The new coalition Government has announced that it proposes to abolish the IPC and replace it with a Major Infrastructure Unit which would form part of the Planning Inspectorate.

ITER

Originally the International Thermonuclear Experimental Reactor (ITER) this is an international tokamak research/engineering project that could help to make the transition from today's studies of plasma physics to future electricity-producing fusion power plants. ITER is based on the 'tokamak' concept of magnetic confinement, in which the plasma is contained in a doughnut-shaped vacuum vessel. The fuel - a mixture of Deuterium and Tritium, two isotopes of Hydrogen - is heated to temperatures in excess of 150 million°C, forming a hot plasma. Strong magnetic fields are used to keep the plasma away from the walls; these are produced by superconducting coils surrounding the vessel, and by an electrical current driven through the plasma. The project aims to demonstrate that it is possible to produce commercial energy from fusion.

JET

The Joint European Torus fusion research project based at Culham and operated by UKAEA on behalf of Euratom.

Light water reactor

Light water reactors use ordinary water as both a moderating material and  a reactor coolant. It includes boiling water reactors (BWRs) and pressurized water reactors (PWRs), the most common types used in the United States.

LLW 

Low-Level Waste:  Waste which includes metals, soil, building rubble and organic materials, arising principally as lightly contaminated miscellaneous scrap. Wastes other than those suitable for disposal with ordinary refuse, but not exceeding 4 GBq/te (gigabecquerels) of alpha or 12 GBq/te of beta/gamma activity. Metals are mostly in the form of redundant equipment. Organic materials are mainly in the form of paper towels, clothing and laboratory equipment that have been used in areas where radioactive materials are used – such as hospitals, research establishments and industry. The National Repository for LLW is near Drigg, Cumbria. 

LLWR

Low Level Waste Respository

LMU 

Liabilities Management Unit:  A unit set up within the DTI (Department of Trade and Industry, now BIS) to strengthen its ability to drive forward work on the nuclear legacy and help to prepare the ground for the NDA. (For more information see the White Paper – Managing the Nuclear Legacy.)

LTP

Lifetime Plan: A document describing the totality of the activities in terms of scope, schedule and cost to be undertaken at each site to transition from the current state to the proposed End State. Submitted annually from the sites to the NDA.

M&O (Contract)

Management and Operations (Contract): A term relating to the day-to-day running of the sites by the SLC in accordance with the contract with the NDA.

Magnox

First generation UK reactor, so called because of the magnesium alloy cladding used to contain uranium fuel rods.

MOX Fuel

Mixed Oxide Fuel: A blend of oxides of plutonium and natural uranium, reprocessed uranium, or depleted uranium which behaves similarly (though not identically) to the low enriched uranium feed for which most nuclear reactors were designed. MOX fuel is an alternative to low enriched uranium fuel used in the light water reactors that predominate nuclear power generation.

Multi Package Contract

Under a multiple package contract (often referred to in the UK as 'multi- contracting' or 'construction management'), the plant owner, with the assistance of an A/E (or construction manager) and other consultants, assumes overall responsibility for managing the design and construction of the project. 

National Nuclear Laboratory 

The UK's National Nuclear Laboratory, based at Sellafield, is a leading nuclear technology services provider. It specialises in providing customers with tailored solutions by applying the right level of technical innovation and intellectual support.

NDA

Nuclear Decommissioning Authority: An NDPB set up in 2005 to oversee the decommissioning and clean-up of the UK's designated civil nuclear legacy. Its sponsoring department is DECC.

NDA sites

Berkeley, Bradwell, Calder Hall, Capenhurst, Chapelcross, Culham, Dounreay, Dungeness A, Harwell, Hinkley Point, Hunterston A, LLWR, Oldbury, Sellafield, Sizewell A, Springfields, Trawsfynydd

New Build Utilities

The UK Government is hoping utilities will deliver up to ten new build nuclear stations in the UK by 2025, with construction of the first plants starting in 2013. At present, the three nuclear new build utilities are: EDF, Horizon and GDF Suez/SSE/Iberdrola (a consortium).

NI

Nuclear island – that part of an NPP which incorporates all equipment, systems, installation and control and other relevant hardware installed within the reactor and reactor auxiliary buildings.  The boundaries of the NI are normally defined as being one metre outside the external boundaries of the above mentioned buildings in the case of piping and two metres for cable.

An NPP is divided into two main parts i.e. the nuclear island and the conventional island.   

The nuclear island is further sub-divided into the NSSS and the balance of nuclear island i.e. everything else that needs to be designed, constructed and tested to complete the nuclear island. 

The conventional island is sub-divided into the turbine generator (i.e. the plant that converts the nuclear steam into electricity) and everything else that needs to be designed, constructed and tested to complete the conventional island i.e. the balance of conventional island.   

NIA

Nuclear Industry Association (NIA) is the trade association and representative voice of Britain's civil nuclear industry. It represents more than 200 companies including the operators and vendors of nuclear power stations, those engaged in decommissioning, waste management, nuclear liabilities management and all aspects of the nuclear fuel cycle, nuclear equipment suppliers, engineering and construction firms, nuclear research organisations, and legal, financial and consultancy companies.

http://www.niauk.org/

NII

Nuclear Installations Inspectorate: Part of the HSE and responsible for regulating the safety of nuclear sites in the UK. This is done through a system of site licensing.

Nirex

Nuclear Industry Radioactive Waste Executive:  The company established to manage the long-term disposal of ILW arising from nuclear waste management and decommissioning.  In October 2006 the Government announced that the functions of Nirex would transfer to the NDA.  The integration of Nirex into the NDA was completed on 2 April 2007 and forms part of the Radioactive Waste Management Directorate.

NPP

Nuclear power plant – (1) a nuclear reactor or reactors together with all structures, systems and components necessary for the safe generation of electricity and/or heat

(2) An electrical generating facility using a nuclear reactor as its heat source to provide steam to a turbine generator.

NSSS

Nuclear steam supply system – that part of an NPP which incorporates the nuclear heat source, the heat transport system and other systems directly connected to the NSSS. 

Nuclear Energy

The energy released by a nuclear reaction (either fission or fusion) or by radioactive decay.

Nuclear fuel cycle

The stages in which the fuel for nuclear reactors is first prepared, then used, and later reprocessed for possible use again. Waste management is also considered part of the cycle.

Nuclear Reactor

1. A device in which nuclear fission may be sustained and controlled in a self-supporting nuclear reaction. The varieties are many, but all incorporate certain features, including fissionable material or fuel, a moderating material (unless the reactor is operated on fast neutrons), a reflector to conserve escaping neutrons, provisions of removal of heat, measuring and controlling instruments, and protective devices. The reactor is the heart of a nuclear power plant.

2. A device in which a fission chain reaction can be initiated, maintained, and controlled. Its essential components are fissionable fuel, moderator, shielding, control rods, and coolant.

Nuclear Supply Chain

The system of organisations, people, technology, activities, information and resources involved in moving nuclear energy from generator/supplier to customer.

OND

Office for Nuclear Development: Part of DECC, its remit is to facilitate new nuclear investment in the UK:

• enable operators to build and operate new nuclear power stations in the UK from the earliest possible date and to enable new nuclear to make the fullest contribution it is capable of, with no public subsidy, and with unnecessary obstacles removed

• build and maintain the UK as the best market in the world for companies to do business in nuclear power

• create and support a globally competitive UK supply chain, focusing on high value added activities to take advantage of the UK and worldwide nuclear programme

• and to support and advise the Secretary of State on nuclear safety, security and safeguards, ensure continued progress with waste management and decommissioning and to implement the UK Governments Global Threat Reduction Programme (non proliferation)

PBO

Parent Body Organisation. The shareholder of the relevant SLC which is incentivised by the NDA to achieve 'more decommissioning for less'.

The principal roles of the PBO are:

• to hold shares in the SLC;
• to second staff to the SLC;
• to provide normal parent company functions; and
• to improve the capability and performance of the SLC.

The current PBOs are:

• Nuclear Management Partners (holding shares in Sellafield Limited);
• Reactor Sites Management Company Limited (holds shares in Magnox North Limited and Magnox South Limited);
• UKAEA Limited (Babcock) (holds shares in Research Sites Restoration Limited and Dounreay Site Restoration Limited as at July 2010 pending competition outcome);
• UK Nuclear Waste Management Limited (holds shares in LLW Repository Limited); and
• Westinghouse Electric UK Limited (holds shares in Springfields Fuels Limited).

POCO

Post Operational Clean Out: The first stage in preparing plant for care and maintenance after operations have ceased.

Pond

Water storage facility for encased nuclear waste

Pool reactor

Reactor in which fuel elements are submerged in an open water pool. The water serves as a moderator, reflector and coolant. Popularly called a "swimming pool reactor," it is used for research and training, not for electrical generation.

Pressure vessel

This is a closed, strong-walled container housing the core of most power reactors. It usually also contains the moderator, neutron reflector, thermal shield, and control rods.

PWR

Pressurised Water Reactor: A reactor whose primary coolant is maintained under such a pressure that no bulk boiling occurs. The reactor uses water as a moderator or as a coolant. In the UK, Sizewell B is one such reactor operated by British Energy.

Radioactivity

The spontaneous emission of radiation, generally alpha or beta particles, often accompanied by gamma rays, from the nucleus of an unstable isotope. Also, the rate at which radioactive material emits radiation. Measured in units of becquerels or disintegrations per second.

Remediation 

A general term for providing a remedy. Environmental remediation deals with the removal of pollution or contaminants from soil, groundwater, sediment, or surface water etc, for the general protection of human health and the environment. 

Renewables Obligation

The current main mechanism for supporting large scale generation of renewable electricity in the UK. It was introduced in April 2002 and places an obligation on UK suppliers of electricity to source an increasing proportion of their electricity from renewable sources.

Renewables Obligation Certificates (ROCs)

A Renewables Obligation Certificate (ROC) is a Green Energy Certificate issued to an accredited generator for eligible renewable electricity generated within the United Kingdom and supplied to customers within the United Kingdom by a licensed electricity supplier. Suppliers meet their obligations under the Renewables Obligation by presenting sufficient Renewables Obligation Certificates. Where suppliers do not have sufficient ROCs to meet their obligations, they must pay an equivalent amount into a fund, the proceeds of which are paid back on a pro-rated basis to those suppliers that have presented ROCs. 

Repository

Long term radioactive waste storage facility.

Reprocessing

The removal of the metal casing from around the fuel and dissolving the fuel in hot, concentrated nitric acid. The uranium, plutonium and waste, which are dissolved in this way, are then separated from each other using several chemical processes. In the UK this work is carried out at Sellafield.

RSRL

Research Sites Restoration Limited: The site licence company at the Harwell and Winfrith sites. The staff were all formerly part of UKAEA but a new company was established and became the SLC on 2 February 2009 as a precursor to competing the role of PBO.

Safeguards

1. A term used in the regulation of domestic nuclear facilities and materials. The use of material control and accounting programs must verify that all special nuclear material is properly controlled and accounted for, and the physical protection equipment and security forces.

2. As used by the International Atomic Energy Agency (IAEA), verifying that the "peaceful use" commitments made in binding non-proliferation agreements, both bilateral and multilateral, are honoured.

Site Licence

A licence granted pursuant to the Nuclear Installations Act 1965.

Site Licence Conditions

The Nuclear Installations Act 1965 (as amended) (NIA65) requires HSE to attach conditions to nuclear site licences. Licence conditions define areas of nuclear safety to which a licensee should pay attention to ensure safe operation of the site. While some conditions impose specific duties others require the licensee to devise and implement adequate arrangements in particular areas. The issues covered range from arrangements for ensuring the safety of plant and for controlling operations to management issues such as the supervision and training of staff. Breach of a licence condition is an offence under NIA65 s.4(6).

A schedule of 35 standard conditions was incorporated into all nuclear site licences granted between 1990 and 1999. A new licence condition, Licence Condition 36 (LC36), was attached to all nuclear site licences at the end of July 1999. LC36(5) came into effect on 1 August 1999 and LC36(1) - (4) came into effect on 1 April 2000; this delay allowed time for licensees to develop their arrangements to achieve compliance.

SLC

Site Licence Company: The entity that holds the nuclear site licence and the discharge authorisations for a UK nuclear site. In the case of designated sites, the SLC carries out the daily management and operations of the site under an M&O Contract to the NDA.

The SLCs are as follows:

1. Sellafield Limited (comprising Sellafield, including Calder Hall; Windscale & Capenhurst);
2. Magnox North Limited (comprising Chapelcross; Hunterston A; Trawsfynydd; Wylfa & Oldbury);
3. Magnox South Limited (comprising  Berkeley; Bradwell; Dungeness A; Hinkley Point A & Sizewell A);
4. Dounreay Site Restoration Limited (Dounreay only);
5. Research Sites Restoration Limited (comprising Harwell & Winfrith);
6. LLW Repository Limited (low level waste repository near Drigg only); and
7. Springfields Fuels Limited (comprising Springfields plant near Preston, Lancashire).

Spent nuclear fuel

Spent nuclear fuel is fuel removed from a reactor after final use. The main commercial UK fuels are Magnox, AGR and PWR. Typically, spent fuel is made up of approximately 96% un-reacted uranium, 1% plutonium, and 3% waste products. The precise composition depends largely on the type of reactor and the amount of power produced by the fuel.

Split Package contract

The overall responsibility for the design and construction of the project is divided among a relatively small number of contractors, each contractor being in charge of a large package of work. 

SQEP

Suitably Qualified and Experienced Person[nel].

SSA

Strategic Siting Assessment: Part of the regulatory framework which applies to new nuclear which is designed to determine the suitability of potential sites for new nuclear electricity generation. The results of the SSA will inform a subsequent Governmental policy statement on siting for new nuclear power stations, as part of a potential National Policy Statement (NPS) on new nuclear power stations. It will include exclusionary and discretionary criteria, and identify those geographical areas that would be likely to be ruled out, either in whole or part, by the exclusionary criteria. The Government has invited nominations for possible sites for new nuclear power stations. 11 have been nominated which comprise 4 sites from the NDA, two from RWE (in Cumbria) and 5 from British Energy/EDF. The draft Nuclear National Policy Statement published on 9 November 2009 confirmed that 10 of the 11 sites had been assessed as suitable for new build.

THORP

Thermal Oxide Reprocessing Plant at Sellafield. This plant reprocesses spent nuclear fuel from nuclear reactors and separates the uranium and plutonium, which can be reused in mixed oxide fuel, from the radioactive wastes, which are treated and stored at the plant. Construction of THORP started in the 1970s, and was completed in 1994. The plant went into operation in August 1997.

Tier contractors

Tier I contractors - a term used to refer to the PBO/SLC on an NDA site (or the senior 'work stream' contractors in new build).

Tier 2 - these contractors are the main interface with the Tier 1 companies  - they hold a direct contract with the Tier 1 companies, which can include, for example, the supply of services on the licensed site

Tier 3 & 4 - these are often SMEs who generally contract with Tier 2 contractors in support of the Tier 2's contract with Tier 1 

Turnkey Contract

(procurement structure)

A single contractor or consortium of contractors assumes overall responsibility for completing all parts and all phases of the project design and construction and assumes the majority of the key project risks.

UKAEA (UKAEA is only responsible for the programme of research at Culham)

United Kingdom Atomic Energy Authority: UKAEA is a Non-Departmental Government Body which has a historical role in Nuclear Research. It conducted pioneering research into Nuclear Energy between the 1940s and 1960s. UKAEA manages the nuclear research programme and Fusion Research in the UK (Joint European Torus - JET at Culham).

Volunteerism

In terms of current nuclear issues, a voluntary expression, by a local community, of an interest to host an underground nuclear waste facility in return for a package of ongoing incentives provided by the NDA/Government. Throughout the cooperative process the needs and concerns of the potential host community are addressed, with the aim of creating a mutually beneficial working partnership between host community and the NDA/Government.

Westinghouse

The designer/manufacturer of the AP1000 nuclear reactor, one of the two designs included within the GDA. Provides fuel, services, technology, plant design and equipment to utility and industrial customers in the worldwide commercial nuclear electric power industry. It has a contract with the NDA for the management of the Springfields site. Westinghouse was sold by BNFL to Toshiba in 2006.