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 Hunterston B Local Liaison Committee and covers activities associated with the regulation of safety at Hunterston B Nuclear Power Station. These reports are distributed quarterly. Site Inspectors of HM Nuclear Installations Inspectorate normally attend LLC meetings and will respond to any questions raised there or subsequently by members of the LLC. Any other person wishing to inquire about matters covered by this report should contact the HSE, Nuclear Directorate Information Centre on 0151 - 951 - 4103.
This report will be put onto the HSE website at: http//www.hse.gov.uk/nsd/nsdhome.htm
- under the heading: Local Liaison Committee Reports.Routine inspections continued in accordance with our annual plan. The HMNII Site Inspector made the following planned visits during the period:
10 – 14 January
31 January – 4 February
21 – 24 March
The planned visits to Hunterston B included a joint inspection with SEPA and also a separate NII benchmarking inspection into the site’s control and supervision arrangements.
During this quarter the Hunterston B reactors have had a fairly steady period of operation; however, there was a short shutdown of Reactor 3 to carry out repairs to its main boiler feed pump.Inspections are undertaken for the purpose of monitoring compliance with the conditions attached by HSE to the nuclear site licences, and other relevant provisions of the Health and Safety at Work etc Act 1974, including the Ionising Radiations Regulations 1999.
The routine inspections for this quarter, covering a range of aspects of plant operation, maintenance, and management were completed. Reactive inspection has also been carried out, with the more significant items reported below. In areas where opportunities for improvement were identified, remedial work has been agreed with station management, with the intention of achieving improvements to current station arrangements.
Liaison with Other Government Departments – SEPA
A joint inspection was carried out with the SEPA Inspector to cover a number of areas of common interest including the status of installation of testing arrangements for all filter installations; and maintenance and testing of ventilation equipment. No significant issues were identified from this joint inspection.
Team Inspection of Control and Supervision of Operations
A benchmarking team inspection into control and supervision and the alignment of essential plant and equipment was carried out at Hunterston B, following on two earlier inspections at British Energy’s Sizewell B and Dungeness B reactor sites.
At Hunterston B, NII noted that t he station had recognised a number of shortcomings in its plant alignment and control arrangements and had initiated a recovery project. Overall, NII’s view was that this project still had some way to go before the full benefits would be realised. The site inspector intends to monitor this recovery project.
Gas circulator endurance modification for the boiler tube fault study case .
BEG(UK)L submitted safety documentation for NII’s agreement to the implementation of modifications which are aimed at improving the performance of the Hunterston B gas circulators in the event of boiler tube leaks. The modification is being implemented in stages.
The nuclear safety issues associated with the initial modification were considered by NII, and it was judged that an adequate safety case had been produced to justify the implementation of the gas circulator endurance modifications. Prior to the routine operation of the final system, NII intend to carry out further assessment of the subsequent stages.
Licence Instrument No. 502 was issued to BEG(UK)L agreeing to the implementation of the gas circulator endurance modification.
Reactor 4 Outage Intentions Meeting
NII attended the outage intentions meeting and was appraised of the work planned for the forthcoming periodic outage for Reactor 4 in June 2005.
A number of issues were discussed, notably the core inspection strategy for Reactor 4. Further meetings are planned to ensure that an agreed position is reached on the outage proposals.
Relicensing the Hunterston B Site to British Energy Generation Limited
BEGL has applied for new nuclear site licences for Hunterston B [and Torness] to allow all of the sites across its fleet to be brought under a single company.
As part of this process BEGL and BEG(UK)L have submitted applications to SEPA for agreement to the transfer of RSA (Radioactive Substances Act) discharge authorizations for Hunterston B from BEG(UK)L to BEGL. The target date for relicensing the site is 1 July 2005, which is coincident with the planned transfer to BEGL of the RSA authorisations.
NII confirmed to SEPA that since the matter only related to a transfer of company name and not to a variation in the conditions and limitations of the authorisations; then we saw no reason for the transfer not to be granted.
NII responds to non-routine events that may affect safety. As part of inspection activities at the site, we investigate safety related events that occur and follow-up those which are perceived initially to have the potential to be more significant. In particular, we examine the licensee’s response to such events. From our inspections in this quarter we were satisfied that the response by the station has been in accordance with appropriate arrangements.
This event related to the standby pump of a reactor Auxiliary Cooling Water system being found to be in local (manual) mode when this should have been in automatic mode owing to the incorrect position of a switch on a local panel.
The nuclear safety significance of this event was that there could have been a loss of cooling to the reactor auxiliary equipment, which could have lead to a possible reactor trip.
The licensee’s on-going investigation to this event was considered to be adequate by NII; however, this event was another example of HNB failing to ensure the correct alignment of safety related plant, which reinforced ND’s view of the need for benchmarking inspections in this area.
This event related to the erection of scaffolding in the new fuel cell, whilst new fuel was present, in contravention of Technical Specification and criticality certificate requirements.
A small scaffold was erected in the new fuel cell box opening room. No limits associated with the new fuel were exceeded; however the ‘secondary’ limits which place restrictions on the presence of unauthorized material were not complied with, ie to prevent the inadvertent introduction of moderator in the vicinity of fissile materials. The event was assigned an INES rating of 1, which is considered to be appropriate, and a formal investigation was carried out.
The licensee’s investigation to this event and the corrective actions taken were considered to be appropriate by NII and no regulatory action was judged to be necessary.
The NII has powers under the nuclear site licence to issue Consents, Approvals and Directions. In addition we use licence instruments to issue Specifications, Notifications and Agreements under the conditions of the licence. During the period of this report, the following Agreement was issued:
Licence Instrument No. 502 was issued to BEG(UK)L on , under licence condition 22(1), agreeing to the implementation of the gas circulator endurance modification for the boiler tube fault study case.
Licence Instument Number 500 was issued to Hunterston B on 23 rd December 2004, under licence condition 22(1), agreeing to the installation of replacement Temperature Monitoring Units on Reactors 3 and 4
HM Nuclear Installations Inspectorate April 2005
St Peter’s House
Stanley Precinct
Bootle
Merseyside
L20 3LZ