Office for Nuclear Regulation

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Planned Licence Condition compliance inspection and Trawsfynydd Site Stakeholder Group meeting

Executive summary

Purpose of Intervention

This inspection was one of a series of planned inspections for 2018/19, which are informed by the Office for Nuclear Regulation’s (ONR) Decommissioning Fuel and Waste (DFW) sub-division strategy.   

Interventions Carried Out by ONR

This inspection was to examine the adequacy of Magnox Limited’s (ML) arrangements and their implementation on the Wylfa site for compliance with three Licence Conditions (LC); LC 7 (incidents on the site), LC 32 (accumulation of radioactive waste) and LC 34 (leakage and escape of radioactive material and radioactive waste).  I also undertook follow up enquiries into an event on electrical distribution boards that was reported to me by ML, the licensee.  I was accompanied for the LC 7 inspection and the follow-up enquiry by an ONR electrical engineering specialist inspector.

For LC 7, we focused on the licensee’s review of the distribution board event and also consideration and implementation of operational learning (red and green briefs) on site.  For LC 32 I focused on; the licensee’s proposed programme to characterise intermediate radioactive waste (ILW) on site; proposals for treatment and storage of ILW on or off site prior to final disposal.  For LC 34 I focused on the licensee’s programme for monitoring leakage and escape of radioactive materials and waste on site.

I met with site staff to discuss possible implications to Wylfa of the revised Radiation (Emergency Preparedness and Public Information) Regulations, which are currently expected to be laid before Parliament in 2019.

I attended the Trawsfynydd Site Stakeholders’ Group meeting where I presented my report on ONR’s regulatory interactions with site between April and October 2018.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable.

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

Based on the evidence examined it is my judgement that ML is effectively implementing arrangements for complying with LC 7, 32 and 34 at Wylfa.  I identified a number of areas of good practice and some areas where ML could improve. I will follow up these areas for improvement as part of my routine interactions with site.

We identified apparent shortfalls in the implementation of arrangements on site for compliance with the Electricity at Work Regulations 1989, specifically Regulation 16.  I have identified areas where I will be seeking improvement, which I have included in a Regulatory Issue.  I utilised ONR Enforcement Management Model guidance to determine the enforcement decision for this event, in line with ONR’s Enforcement Policy Statement.  In this instance, I judge that issuing an enforcement letter is the appropriate action to take.

Conclusion of Intervention

I identified no matters that in my opinion could adversely affect nuclear safety. My findings were shared with and accepted by the licensee.  


Pwrpas yr Ymyriad

Roedd yr arolwg hwn yn un o gyfres o arolygiadau a gynlluniwyd ar gyfer 2018/19, sydd wedi eu seilio ar strategaeth isadran Datgomisiynu, Tanwydd a Gwastraff (DFW) y Swyddfa dros Reoli Niwclear (ONR).   

Ymyraethau a Gyflawnwyd gan yr ONR

Bwriad yr arolygiad hwn oedd archwilio pa mor ddigonol yw trefniadau Magnox Limited (ML) a’u gweithrediad ar safle Wylfa o ran cydymffurfio â thair Amod Trwyddedu (LC); LC 7 (digwyddiadau ar y safle), LC 32 (crynhoad o wastraff ymbelydrol) a LC 34 (deunydd ymbelydrol a gwastraff ymbelydrol yn gollwng neu’n cael ei golli).  Cynhaliais ymholiadau dilynol hefyd am ddigwyddiad ar fyrddau dosbarthu trydanol y rhoddwyd adroddiad i mi amdano gan ML, y trwyddedai.  Daeth arolygydd arbenigol peirianneg trydanol o’r ONR gyda mi i wneud yr arolygiad LC 7 a’r ymholiad dilynol.

Ar gyfer LC 7, roeddem yn canolbwyntio ar adolygiad y trwyddedai o’r digwyddiad bwrdd dosbarthu a hefyd yr ystyriaeth a’r gweithredu ar ddysgu gweithrediadol (briffs coch a gwyrdd) ar y safle.  Ar gyfer LC 32 canolbwyntiais ar; raglen arfaethedig y trwyddedai i nodweddu gwastraff ymbelydrol canolradd (ILW) ar y safle; y cynigion ar gyfer trin a storio ILW ar y safle neu oddi arno cyn ei waredu yn derfynol.  Ar gyfer LC 34 canolbwyntiais ar raglen y trwyddedai ar gyfer monitro’r deunydd ymbelydrol sy’n gollwng a chael ei golli a’r gwastraff ar y safle.

Cyfarfyddais y staff safle i drafod oblygiadau posibl y Rheoliadau Ymbelydredd (Parodrwydd ar Gyfer Argyfwng a Gwybodaeth Gyhoeddus) diwygiedig, i Wylfa, y disgwylir iddynt gael eu cyflwyno ger bron y Senedd yn 2019.

Bûm yng nghyfarfod Rhanddeiliaid Safle Trawsfynydd a chyflwynais fy adroddiad ar ryngweithio rheoleiddiol yr ONR â’r safle rhwng Ebrill a Hydref 2018.

Esboniad o’r Dyfarniad os Nad oedd y System Ddiogelwch wedi cael ei Barnu yn Ddigonol

Ddim yn berthnasol.

Casgliadau Allweddol, Barnau’r Arolygydd a Rhesymau dros Wneud Dyfarniadau

Yn seiliedig ar y dystiolaeth a archwiliwyd, fy nyfarniad i yw bod ML yn gweithredu trefniadau i gydymffurfio ag LC 7, 32 a 34 yn Wylfa yn effeithiol.  Nodais nifer o feysydd o arfer da a rhai meysydd lle gallai ML wneud gwelliannau. Byddaf yn dilyn y meysydd hyn i’w gwella fel rhan o’m hymwneud arferol â’r safle.

Dynodwyd diffygion ymddangosiadol gennym yng ngweithrediad y trefniadau ar y safle o ran cydymffurfio â’r Rheoliadau Trydan yn y Gwaith 1989, Rheoliad 16 yn benodol.  Rwyf wedi dynodi meysydd lle byddaf yn chwilio am welliant, yr wyf wedi eu cynnwys mewn Mater Rheoleiddiol.  Defnyddiais y cyfarwyddyd Model Rheoli Gorfodi ONR i bennu’r penderfyniad gorfodi ar gyfer y digwyddiad hwn, yn unol â Datganiad Polisi Gorfodi’r ONR.  Y tro hwn, rwy’n barnu mai rhoi llythyr gorfodi yw’r cam priodol i’w gymryd.

Casgliad yr Ymyrraeth

Ni nodais unrhyw faterion a allai effeithio'n andwyol ar ddiogelwch niwclear. Rhannwyd fy nghasgliadau gyda’r trwyddedai ac fe’u derbyniwyd ganddo.