Health and Safety
Executive / Commission
Nuclear
LLC reports
This report is issued as part of the Health and Safety Executive'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 Dungeness Site Stake-holder Group (SSG) and covers activities associated with the regulation of safety at Dungeness B Power Station. These reports are distributed quarterly. Site Inspectors of HM Nuclear Installations Inspectorate (part of the Health and Safety Executive's Nuclear Directorate) attend LCLC meetings and will be happy to respond there to questions raised by members of the LCLC. Any person wishing to inquire about matters covered by this report should contact the HSE, Nuclear Directorate on 0151-951-3484/3290
This report will be placed on the HSE website at
http://www.hse.gov.uk/nuclear/index.htm
Nuclear Directorate
Health and Safety Executive
St Peter’s House
Balliol Road
Bootle
Merseyside
L20 3LZ
1.1 The Nuclear Installations Inspectorate (NII) Site Inspector visited Dungeness B on the following dates during the quarter covered by this report:
17– 19 January
24 – 26 January
7-9 February
6-9 March
1.2 Other NII inspectors with specialist technical expertise also visited Dungeness B and other British Energy establishments during the period to support the Site Inspector by performing inspections on specific aspects of the Licensee’s arrangements and nuclear safety case.
1.3 On 7 – 8 March the station was visited by NII’s Superintending Inspector with responsibility for overseeing the regulation of nuclear safety at Dungeness B and a number of other nuclear power stations to witness the station’s annual demonstration exercise of it emergency arrangements.
1.4 Arrangements were made for the handover of site inspection responsibility for Dungeness B to a new site inspector, in accordance with NII’s routine arrangements, with effect from 1 April 2006.
Routine planned inspections are carried out throughout the year and enable NII to judge whether a Licensee is complying with the conditions attached to the Nuclear Site Licence, the Ionising Radiations Regulations, and other relevant statutory provisions on a sampling basis. Compliance with the following Licence Conditions was inspected during the period:
In general the station’s arrangements were found to be satisfactory. In those areas where improvements were identified, satisfactory commitments to address the issues were made by the station. Routine aspects of particular significance are summarised below.
Emergency Arrangements
An NII team witnessed the Licensee’s annual “Level 1” demonstration emergency exercise on 8 March. The NII team concluded that this had been an adequate demonstration of the Licensee’s emergency arrangements.
Outage Intent Meeting
The Reactor 21 periodic shutdown is currently scheduled to take place from 21 April, although the Licensee has sought HSE approval for the reactor to operate up to and including 14 May 2006, pending repairs to the Fuelling Machine. A meeting was held on 8 February to discuss the Licensee’s detailed proposals for work to be carried out during the outage. NII concluded that these proposals were broadly satisfactory.
Defective Fuel Elements
As previously mentioned, in the Spring of 2005 NII became concerned that 9 fuel elements with very small defects were known to be present in the two operating reactors. Whilst recognising the low probability that any one defect would develop into a significant failure, we pressed for early removal of the defective fuel elements. The Licensee subsequently committed to a programme under which all elements known to be defective should have been removed from the reactors by April 2006. This has been a key focus for the station. However, recent faults on the Fuelling Machine have resulted in 2 of the defective elements remaining in the reactors at the end of the reporting period.
Fuelling Machine Repair
The Licensee has identified a need to change two wheel bearings on the Fuelling Machine. This will require one side of the structure to be jacked up slightly (by around 1 millimetre) to enable the wheels to be removed. NII specialists are monitoring the Licensee’s proposals for this work, which could have serious nuclear safety implications if inadequately conceived or executed.
Required Actions not Taken
On 5 January 2006 it was discovered that staff operating the reactors had not been told of defects on a fire extinguisher system. These had been identified during earlier routine maintenance tests. As a result, actions required to ensure compliance with the station’s Operating Rules (known as Technical Specifications) were not taken. The site inspector has reviewed the Licensee’s preliminary response to this event and is content with the actions taken.
Under Health and Safety legislation the Site Inspector, or other HSE Inspectors, may issue formal notices to secure improvements to safety. No such notices were issued during the reporting period.
The Inspectorate has powers under the Licence to issue Consents, Approvals and Directions. In addition the Inspectorate uses Licence Instruments to issue Specifications and Agreements under the conditions of the Licence. These are all called Licence Instruments. In accordance with formal regulatory procedure, NII issued the following Licence Instrument to Dungeness B under Site Licence No. 61 during the reporting period: