Office for Nuclear Regulation

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Site inspection - Wylfa

Executive summary

Purpose of intervention

This was a planned inspection at Magnox Ltd's (ML) Wylfa site, undertaken as part of the Decommissioning, Fuel and Waste (DFW) Programme strategy and planned inspection programme for 2016/17.

Interventions Carried Out by ONR

Planned inspections of Licence Conditions (LCs) 7 and 26 were undertaken.

ONR Mechanical Engineering Nuclear Associate supported a reactive inspection into increasing backlog of defects.

Additional meetings were undertaken to review the following matters:

Explanation of Judgement if Safety System Not Judged to be Adequate

No safety system based inspections were undertaken during this intervention.

Key Findings, Inspector's Opinions and Reasons for Judgements Made

The planned compliance inspections for LCs 7 and 26 were undertaken as part of a review of the fuel route performance and action plan arising from a recent peer assist that sought to make changes to provide improved response times to breakdowns at the site and minimise risks to delivering the defuelling programme in line with the Magnox Operating Programme at Sellafield. It is evident from the inspections that were undertaken that the site continues to ensure SQEP resource is available to support safe fuel route operation and that in combination with key issues meetings and local work management activities suitable levels of control and supervision are being maintained. Furthermore, the learning from recent operational breakdowns and maintenance activities is resulting in changes to how work is managed and delivered to minimise downtime arising from unexpected breakdowns. The action plan arising from the peer assist is evidently being delivered and oversight maintained within the organisation to ensure progress of specific actions.

The reactive inspection of maintenance arose following quarterly performance indicators being monitored by ML, have been showing increasing plant defect backlogs at Wylfa. High priority work requests (P1) continue to be addressed promptly, however the lower priorities (P2 and P3) have not been as successfully managed. It was evident that ML is actively addressing the backlogs and making progress towards reducing these to a more acceptable level. A reinvigoration of expectations and some improvements have been made to the arrangements and the issue is being closely monitored by ML.

Additional meetings confirmed that ML is continuing to maintain focus on competing demands and seeking opportunities to ensure legal obligations are delivered in a proportionate manner.

Conclusion of Intervention

From the information obtained and evidence gathered during this intervention, I believe there were no issues identified that were considered to adversely affect nuclear safety.

Crynodeb gweithredol

Pwrpas yr Ymyrraeth

Roedd hwn yn arolygiad cynllunedig o safle Wylfa Magnox Cyf., a wnaed fel rhan o'r rhaglen strategaeth ac arolygiad cynllunedig y Rhaglen Datgomisiynu, Tanwydd a Gwastraff (DFW) ar gyfer 2016/17.

Ymyriadau a Wnaed gan ONR

Gwnaed arolygiadau cynllunedig o Amodau Trwydded (LCs) 7 a 26.

Fe wnaeth ONR Mechanical Engineering Nuclear Associate gefnogi aroylgiad adweithiol ar ôl-groniad cynyddol o ddiffygion.

Ymgymerwyd â chyfarfodydd ychwanegol i adolygu'r materion dilynol:

Esboniad o'r Dyfarniad os Na Ddyfernir bod y System Ddiogelwch yn Ddigonol

Ni wnaed unrhyw arolygiadau seiliedig ar system ddiogelwch yn ystod yr ymyrraeth hon.

Canfyddiadau allweddol, Barnau'r Arolygydd a Rhesymau am Ddyfarniadau a Wnaed

Gwnaed yr arolygiadau cynllunedig ar gyfer LCs 7 a 26 fel rhan o adolygiad o berfformiad y llwybr tanwydd a'r cynllun gweithredu'n codi o gymorth diweddar gan gyfoed a oedd yn ceisio gwneud newidiadau i ddarparu amseroedd ymateb gwell i doriadau ar y safle a lleihau risgiau ynghylch cyflenwi'r rhaglen datlenwi yn unol â Rhaglen Gweithredu Magnox yn Sellafield. Mae'n amlwg o'r arolygiadau a wnaed bod y safle'n parhau i sicrhau bod adnodd SQEP ar gael i gefnogi'r llwybr tanwydd diogel weithredu ac, ar y cyd â chyfarfodydd ynghylch materion allweddol a gweithgareddau lleol ynghylch rheoli gwaith mae lefelau addas o reolaeth a goruchwyliaeth yn cael eu cynnal. Ymhellach, mae'r gwersi o doriadau gweithredol diweddar a gweithgareddau cynnal yn arwain at newidiadau ynghylch sut mae gwaith yn cael ei reoli a'i gyflenwi i leihau amser segur sy'n codi o doriadau annisgwyl. Mae'n amlwg bod y cynllun gweithredu'n codi o'r cymorth gan gyfoed yn cael ei gyflenwi a bod goruchwyliaeth yn cael ei chynnal o fewn y sefydliad i sicrhau cynnydd camau gweithredu penodol.

Cododd yr arolygiad adweithiol o waith cynnal a chadw yn dilyn dangosyddion perfformiad chwarterol oedd yn cael eu monitro gan ML, a maent wedi bod yn dangos ôl-groniadau o ddiffygion mewn offer yn Wylfa. Mae ceisiadau gwaith blaenoriaethol (P1) yn dal i gael eu trafod yn brydlon, fodd bynnag nid yw'r blaenoriaethau is (P2 and P3) wedi'u rheoli mor lwyddiannus. Roedd yn amlwg bod ML yn trafod yr ôl-groniadau'n weithgar ac yn gwneud cynnydd tuag at leihau'r rhain i lefel fwy derbyniol. Mae ailfywiogi disgwyliadau a rhai gwelliannau wedi'u gwneud i'r trefniadau ac mae'r mater yn cael ei fonitro'n agos gan ML.

Fe wnaeth cyfarfodydd ychwanegol gadarnhau bod ML yn parhau i gynnal ffocws ar alwadau sy'n cystadlu ac yn ceisio cyfleoedd i sicrhau bod goblygiadau cyfreithiol yn cael eu cyflenwi mewn modd priodol.

Casgliad yr Ymyrraeth

O'r wybodaeth a gafwyd a'r dystiolaeth a gasglwyd yn ystod yr ymyrraeth hon, credaf na nodwyd unrhyw broblemau yr ystyriwyd eu bod yn effeithio'n niweidiol ar ddiogelwch niwclear.