Office for Nuclear Regulation

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Quarterly site report for Sizewell A Site

01 October 2011 to 31 December 2011


This report is issued as part of the Office for Nuclear Regulations (ONR's) commitment to make information about inspection and regulatory activities relating to the above site available to the public. It is for distribution to members of the Sizewell Site Stakeholder Group and covers activities associated with the regulation of safety at the Sizewell A Site. These reports are distributed quarterly and are also available on the ONR website.

Site inspectors of the ONR usually attend Sizewell Site Stakeholder Group meetings and will respond to any questions raised there by the members of the group. Any other person wishing to inquire about matters covered by this report should contact ONR.

Post: Office for Nuclear Regulation
Redgrave Court
Merton Road
L20 7HS


The Office for Nuclear Regulation (ONR) Site Inspector made an inspection on the following dates during the quarter:

Routine matters

Inspections at site

Inspections at Sizewell A are undertaken at site as part of the process for monitoring compliance with:

  1. the conditions attached by HSE / ONR to the nuclear site licence;
  2. the Health and Safety at Work etc Act (HSWA) 1974; and
  3. regulations made under the HSWA (for example the Ionising Radiations Regulations 1999 and the Management of Health and Safety at Work Regulations 1999).

This entails monitoring licensees actions on the site in relation to incidents, operations, maintenance, projects, modifications, safety case changes and any other matters which may affect safety. The licensees/operators are required to make and implement adequate arrangements under the conditions attached to the licence in order to ensure legal compliance. Inspections seek to judge both the adequacy of these arrangements and their implementation. In this period, routine inspections of Sizewell A covered:

In general, the arrangements made and implemented by the site in response to safety requirements were deemed to be adequate in the areas inspected. However, where improvements were considered necessary, satisfactory commitments to address the issues were made by the licensee, and the Site Inspector will monitor progress during future visits. Where necessary, formal regulatory enforcement action will be taken to ensure that appropriate remedial measures are implemented to reasonably practicable timescales.

Non-routine matters

Licensees are required to have arrangements to respond to non-routine matters and events. ONR inspectors judge the adequacy of the licensees response, including actions taken to implement any necessary improvements.

In the previous SSG report, ONR noted the occurrence of a leak of treated pond water from a damaged glass flow meter in the Sizewell A Active Effluent Treatment Plant (AETP) on 3 September 2011.

Whilst ONR remains satisfied that any risk to workers was negligible, and that the leak was contained entirely within the AETP facility (and hence presented no risk to members of the public), it undertook a formal assessment of the event to:

Whilst ONR is satisfied that Magnox Limited responded effectively to the event, has conducted a thorough investigation, has identified appropriate learning, and has demonstrated a high level of commitment to delivering appropriate improvements, ONR's assessment report concludes that Magnox did not secure compliance with all of its legal duties in this instance.

Consequently, ONR has delivered proportionate enforcement action (in the form of a formal letter) which records the nature of the non-compliances and which sets out ONR's expectations of Magnox Limited going forwards.

ONR will monitor Magnox Limited's progress in delivering these expectations.

Regulatory activity

Under health and safety legislation, ONR site inspectors, and other HSE inspectors, may issue formal documents to ensure compliance with regulatory requirements. Under nuclear site licence conditions. ONR issues regulatory documents, which either permit an activity or require some form of action to be taken. These are usually collectively termed licence instruments (LIs), but can take other forms. In addition, inspectors may issue enforcement notices to secure improvements to safety.

The regulatory documents issued in this quarter were:

Reports detailing the above regulatory decisions can be found on the ONR website.

News from ONR

Final Fukushima report

The final report, 11 October, revealed no fundamental safety weaknesses in the UK's nuclear industry but concluded that by learning lessons it can be made even safer. The report, the Governments response and a podcast featuring Mike Weightman is available on the ONR website. A report will be published next year on progress in implementing the lessons for the UK.

Radioactive Materials Transport Team (RMTT) joins ONR

The team joined ONR from the Department of Transport on 24 October. The team is responsible for regulating the transport of radioactive material by road and rail in Great Britain, as well as advising on transport by sea and air within the United Kingdom.  Their remit covers the transport of material to and from licensed nuclear sites and non-nuclear sectors such as hospitals and education establishments.  

Non Governmental Organisations Forum

ONR's second NGO forum was held in London (17 November). Topics covered included openness and transparency, generic design assessment and the final Fukushima report. The forum was well attended with constructive discussion sessions. Minutes have been published on ONR's website, and a third forum will be held in April 2012.

International Physical Protection Advisory Service (IPPAS) mission

A team of international nuclear security experts led by the International Atomic Energy Agency (IAEA) visited the UK in October to assess civil nuclear security arrangements. They concluded the state of civil nuclear security in the UK to be sufficiently robust and identified many examples of good practice within the civil nuclear security regime and a number of valuable recommendations and suggestions.

Senior representatives conference

The annual event bought together nuclear industry leaders on 14 November. Discussions focused on: openness and transparency in the post-Fukushima era; promoting a safety culture across all parts of the nuclear industry supply chain; and responding to challenges post-Fukushima.

ONR public consultation update

The 12 week public consultation to clarify ONR's interpretation of bulk quantities relating to radioactive matter closed on 12 December. ONR is now analysing responses to the consultation and will make a policy announcement once a suitable definition is agreed.

Stress tests

ONR received final stress test reports from licensees of UK nuclear power plants by the required date of 31 October. ONR reviewed these reports and provided a UK national report for the European Council at the end of December.

ONR received the progress reports from licensees of other UK nuclear facilities by the required date of 15 October. Final reports are due by 31 December with a report due for publication in Spring 2012.

Generic Design Assessment

On 14 December generic designs for EDF and Areva's UK EPR and Westinghouse's AP1000 reactors were granted interim acceptance by ONR and the Environment Agency. However, neither reactor can be built in the UK until a number of issues are resolved. See GDA for more information.

ONR quarterly report

ONR published online its second and third quarterly reports in November and January respectively.