Office for Nuclear Regulation

This website uses non-intrusive cookies to improve your user experience. You can visit our cookie privacy page for more information.

Wylfa - System based inspection, lifting and handling systems

Executive summary

Purpose of intervention

This was a System Based Inspection (SBI), of nuclear lifting and handling at Magnox Limited's (ML's) Wylfa power station, undertaken as part of the planned inspection programme for 2016/17.

Interventions Carried Out by ONR

An ONR mechanical engineering specialist and nuclear associate undertook a SBI on the mechanical aspects of nuclear lifting and handling at Wylfa power station between the 15th and 16th of November 2016. The licensee, ML, was represented by appropriate personnel from the site. Prior to the intervention, the licensee provided management procedures associated with nuclear lifting and handling which was reviewed by the ONR.

In order to determine the adequacy of implementation of the licensee's safety case claims in respect of this system, ONR examined evidence regarding the implementation of ML arrangements for five pre-defined licence conditions (LCs), as listed below. These LCs have been selected in view of their importance to nuclear safety and are defined within ONR's formal process for system based inspection.

The inspection involved reviewing the applicable safety case claims and sampling, through a combination of document reviews, discussions with operators and plant inspections, suitable evidence to determine compliance against these LCs on the plant.

ONR assessed compliance in ML's lifting and handling arrangements against the following LCs using the applicable ONR inspection guidance:

Explanation of Judgement if Safety System Not Judged to be Adequate

The SBI of nuclear lifting and handling for mechanical engineering systems was judged to be implemented adequately and in accordance with the requirements of the safety cases provided. However, there are specific improvements that ML should make as described in the next section.

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

Whilst some minor opportunities for improvements to ML's compliance against LCs 24, 27 and 28 were identified in this inspection, it is my view that these licence conditions are all adequately implemented with regards to lifting and handling. Consequently, it is my opinion that a rating of GREEN (no formal action) is appropriate for these licence conditions. 9. However, with regard to LC10 (training), based on the sampling undertaken, I have awarded a rating of AMBER (seek improvement). This is due to an inadequate demonstration that suitably qualified and experienced persons (SQEP) were conducting interlock procedures, requiring ML to:

Introduce suitable SQEP arrangements for interlock checks undertaken by Production Technicians (PT) and Super Production Technicians (SPT);

Conclusion of Intervention

I have identified a specific shortfall in respect to the lifting and handling training compliance for interlock instructions, along with several minor improvements associated with completion of improvements already underway. Overall however, based upon the evidence examined during the SBI, I consider ML Wylfa provided an adequate demonstration that lifting and handling arrangements are implemented and meeting the requirements of the supporting safety case.

I have raised a Regulatory Issue as a result of this inspection which I will use to track ML's timely return to full compliance. This relates to the Amber rating I have awarded against LC10 and progression of the other minor improvements which I intend to progress under normal regulatory business.


Pwrpas yr Ymyrraeth

1. Roedd hwn yn Arolygiad Seiliedig ar System (SBI), ar godi a thrafod niwclear yng ngorsaf bwer Wylfa Magnox Cyfyngedig (ML) a wnaed fel rhan o'r rhaglen arolygiadau cynllunedig ar gyfer 2016/17.

Ymyriadau a Wnaed gan ONR

Fe wnaeth arbenigwr peirianneg fecanyddol ONR a chyfrannog niwclear ymgymryd ag SBI ar agweddau mecanyddol codi a thrafod niwclear yng ngorsaf bwer Wylfa rhwng 15fed a16eg Tachwedd 2016. Cynrychiolwyd y trwyddedai, ML, gan bersonél priodol o'r safle. Cyn yr ymyrraeth, fe wnaeth y trwyddedai ddarparu gweithdrefnau rheoli yn gysylltiedig â chodi a thrafod niwclear a adolygwyd gan yr ONR.

Er mwyn penderfynu ar ddigonoldeb proses gweithredu honiadau achos diogelwch y trwyddedai ynghylch y system hon, fe wnaerh ONR archwilio tystiolaeth ynghylch gweithredu trefniadau ML ar gyfer pump amod trwydded a oedd wedi eu rhag-ddiffinio (LCs), fel a restrir isod. Dewiswyd yr LCs hyn oherwydd eu pwysigrwydd i ddiogelwch niwclear ac fe'u diffinir o fewn proses ffurfiol ONR ar gyfer arolygiad seiliedig ar system.

Roedd yr arolygiad yn ymwneud ag adolygu honiadau cymwys yr achos diogelwch a samplo trwy gyfuniad o adolygiadau dogfennau, trafodaethau gyda gweithredwyr ac arolygiadau offer, tystiolaeth addas i benderfynu ar gydymffurfiad yn ôl yr LCs hyn ar yr offer.

Fe wnaeth ONR asesu cydymffurfiad yn nhrefniadau codi a thrafod ML yn ôl yr LCs dilynol gan ddefnyddio cyfarwyddyd arolygu ONR:

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

Dyfarnwyd bod yr SBI codi a thrafod niwclear ar gyfer systemau peirianneg fecanyddol wedi'i weithredu'n ddigonol ac yn unol â gofynion yr achosion diogelwch a ddarparwyd. Fodd bynnag, mae gwelliannau penodol y dylai ML eu gwneud fel a ddisgrifir yn yr adran nesaf.

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

Er bod rhai cyfleoedd mân ar gyfer gwelliannau i gydymffurfiad ML yn ôl LCs 24, 27 a 28 wedi'u nodi yn yr arolygiad hwn, fy marn i yw bod yr holl amodau trwydded hyn yn cael eu gweithredu'n ddigonol ynghylch codi a thrafod. O ganlyniad, fy marn i yw bod gradd GWYRDD (dim camau gweithredu ffurfiol) yn briodol ar gyfer yr amodau trwydded hyn.

Fodd bynnag, ynghylch LC10 (hyfforddiant), yn seiliedig ar y samplo a wnaed, rwyf wedi dyfarnu gradd AMBR (ceisio gwella). Mae hyn oherwydd arddangosiad annigonol bod personau â chymwysterau a phrofiad addas (SQEP) yn cynnal gweithdrefnau cyd-gloi, yn galw ar ML i:

Cyflwyno trefniadau SQEP addas ar gyfer gwiriadau cyd-gloi a wneir gan Dechnegwyr Cynhyrchiant (PT) a Thechnegwyr Arch-gynhyrchiant (SPT);

Casgliad yr Ymyrraeth

Rwyf wedi nodi diffyg penodol ynghylch cydymffurfiad hyfforddiant codi a thrafod ar gyfer cyfarwyddiadau cyd-gloi, gyda nifer o welliannau mân yn gysylltiedig â chwblhau gwelliannau a gychwynnwyd eisoes. Fodd bynnag, ar y cyfan, yn seiliedig ar y dystiolaeth a archwiliwyd yn ystod yr SBI, rwyf yn ystyried bod ML Wylfa wedi darparu arddangosiad digonol bod trefniadau codi a thrafod yn cael eu gweithredu a'u bod yn diwallu gofynion yr achos diogelwch cefnogol.

Rwyf wedi codi Mater Rheoleiddiol o ganlyniad i'r arolygiad hwn y byddaf yn ei ddefnyddio i dracio dychweliad amserol ML i gydymffurfiad llawn. Mae hyn yn perthyn i'r radd Ambr rwyf wedi'i dyfarnu yn erbyn LC10 a chynnydd y gwelliannau mân eraill rwyf yn bwriadu eu cynyddu o dan fusnes rheoleiddiol arferol.