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 Hartlepool Local Community Liaison Council and covers activities associated with the regulation of safety at Hartlepool Power Station. These reports are distributed quarterly and are available also from the Internet at www.hse.gov.uk/nuclear/index.htm. 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 to any questions raised by members of the LCLC. Any person wishing to inquire about matters covered by this report should contact the HSE’s, Nuclear Directorate on 0151-951-3484/3290.
The site inspector visited the site on seven occasions during the quarter:
In addition, specialist NII inspectors visited the site during the period to assist with inspections related to their areas of expertise – quality assurance, civil engineering, radiological protection, fire safety, mechanical engineering, conventional health and safety issues, and control and instrumentation.
As part of their routine work NII inspectors inspect for compliance against the requirements of the Station’s Nuclear Site Licence, the Health and Safety at Work Act and other relevant safety legislation. They monitor events, plant operations, projects, modifications and safety case changes and any other matters which are important to safety. Planned inspections during the quarter included instructions to persons on site (LC9), quality assurance (LC17), radiological protection (LC18), modification to existing plant (LC22), operating rules (LC23), operating instructions (LC24), control and supervision of operations (LC26), and maintenance, inspection and testing (LC28).
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:
Fire dampers are a means of closing ventilation systems which pass between various fire zones, otherwise sealed by walls, doors and other barriers. The fire dampers act to quickly close and seal the ventilation system, helping to prevent the spread of fire. Dampers need to be maintained and controlled to suitable standards and at appropriate intervals. For the fire dampers associated with the nuclear fire safety case, an inspection has highlighted that frequency and standards applied at present need improvement. A letter has been written to the station seeking a programme to address these matters.
An inspection of the Radioactive Waste Treatment Plant identified a build up of material some degradation of the material condition of the area. Whilst risks were being adequately controlled, the lack of ownership of the area was allowing a general deterioration in standards. A letter has been written to the station seeking improvements to the area and its housekeeping.
As part of their planned inspection, site inspectors examine safety related events that have occurred and the Licensee’s response to them. Generally the Licensee’s internal system for following up events is robust and the appropriate actions are implemented. Three events were described in the previous quarter’s report regarding: control rod exchanges, leak testing of sources and an accident involving a forklift truck. The site inspector is satisfied with the progress of the licensee following all three events, with improvements to control rod exchange performance and to the control of all-terrain vehicles on site. The station has yet to respond to a letter asking them to confirm that the backlog of tests of sealed sources has been removed, but the site inspector has confirmed that it is reducing.
A significant number of noteworthy events occurred during this reporting period. A number of these events were rated as level 1 on the International Nuclear Event Scale, and these are described below:
The event occurred on 23rd June when the fuelling machine (FM) was being pressurised with CO 2 to 35 Bar at the blowdown facility. Once pressurised, a flexible hose and the swan neck supply pipework were vented to atmospheric pressure, but the hose was not disconnected. When the FM was subsequently moved, the hose pulled the swan neck supply pipework and the connector failed. The accident did not release any contaminated CO 2, nor was there any injury, nevertheless, the significance of the damage and the failure to stop, make safe and report the damage immediately was of concern. The primary cause of the event was operator error, compounded by a delay in reporting the damage; indeed the event was only upgraded to INES 1 in the first week of July when a clearer understanding of events became available. NII is content with the action being undertaken by station in response to this event.
Laundry from the radiation controlled areas at Hartlepool power station is collected and sent to an active laundry facility in Holland. Approved packages are used for these shipments and there are limits regarding external doserates at the point of dispatch and receipt. On receipt in Holland a package was found to have a point doserate which although low, was in excess of the limit. The station’s investigation has found a number of causal factors including time pressure, and a non-systematic means of inspecting the package prior to dispatch, compared with the facilities in Holland. Changes were made to arrangements prior to shipments being restarted, and a further range of control measures are to be implemented, including a tool to provide a greater assurance of 100% coverage of the surface of the package. The site inspector is content that the revised arrangements are adequate, and the measurement tool should provide further improvement.
The event occurred on 26 th September. A buried cast iron cooling water main fractured close to the Turbine Hall and Reactor Building. The resulting liquefaction of the soil around the supply main damaged services local to the pipe including electrical and other cooling water pipes. Both reactors were shutdown at the time and the alternative buried main together with an overground supply main continued to provide sufficient quantities of cooling water. Investigations to understand the cause of the failure and the degree of damage to surrounding services are ongoing. NII is content that the station do not intend to restart the reactors until the normal cooling configuration is re-established.
The event occurred on 1 st July during the start up of Reactor 1. During the start up, there is a safety case requirement to alter the diverse neutron flux trip settings on 4 occasions, at 600, 800, 1050 and 1710MW. During the setting process, the trip setting was 200MW too high. No actual consequences occurred, but it was a significant near miss and attracted an INES 1 rating. The primary cause of the event was the type of dial used to set the limit, which were very difficult to read. Replacement equipment which includes a digital display of the setting has been sourced and installed on most of the equipment during routine maintenance changeovers, with the remainder to be completed by the end of the year. The site inspector is satisfied that this change, along with a number of others not reported will significantly reduce the likelihood of a repeat or similar event.
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.
Th e 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. The following Licence Instruments were issued to Hartlepool during the quarter:
Licence Instrument 513, Consent, granted under Condition 30(3), consenting to the start up of Reactor 2.
Licence instrument 514, agreeing to a proposal for the use of an alternative bar manufacturing route for the supply of AGR fuel element and stringer components made from 20%Cr/25%Ni Nb-Stabilised Stainless Steel.
HM Nuclear Installations Inspectorate,
31 st October 2006
Redgrave Court
Merton Road
Bootle
Merseyside
L20 7HS