Office for Nuclear Regulation

Harwell LC4 and LC21 compliance inspection

Executive summary

Purpose of Intervention

This inspection was to confirm that Magnox Limited (ML) Harwell Site is complying with various Licence Conditions (LC) in accordance with the 2020/21 inspection plan and to confirm that the licensee is controlling its hazards and complying with its statutory obligations.

Interventions Carried Out by ONR

This inspection was of the Site’s arrangements made under the following LCs:

The inspection was based on examining a sample of the licensee’s arrangements and their implementation on the Harwell Intermediate Level Waste Box Store (HIBS) LC4 & LC21.

I sought to gain evidence that:

Explanation of Judgement if Safety System Not Judged to be Adequate


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

The new HIBS facility is still to be handed over from project to the site facilities management team.  Thereafter there will be a long quiescent period (approximately 4 years) before there is a further handover from the site facilities team to operations for first active use.

As first active use is approximately 4 years away, the inspection against LC4 focussed on the adequacy of the corporate arrangements and the identification of suitable limits and conditions for the import of 6m3 boxes.  There are currently no operating instructions for 6m3 box import available to review at this stage, however I am content that this is identified by the licensee as an action to be implemented by first active use.  I found that the safety assessment identifies suitable conditions and limits for acceptance but note that these are subject to review before active commissioning. I consider that the available information for compliance to LC4 is adequate for the current position in the project lifecycle.  I have noted some inconsistences within the arrangements with respect to definitions of nuclear material and nuclear matter and consider this a minor compliance shortfall.    

Notwithstanding the minor shortfall above I consider that the licensee has adequately implemented their arrangements in place for LC 4.

The inspection against LC21 focussed on the implementation of the corporate arrangements for commissioning in the HIBS project. I found that the licensee has adequate arrangements for commissioning the plant and processes. Operation and maintenance teams have been involved during the commissioning process to gain familiarity with the new facility which I consider good practice. Use of photographic evidence to record compliance in commissioning reports is also commendable. The level of evidence provided was appropriate for the position in the project lifecycle, however I noted a number of minor shortfalls, which I would expect to see resolved as a matter of course prior to facility handover. These will be followed up in future inspections. Notwithstanding the minor shortfalls I consider that the licensee has adequately implemented their arrangements in place for LC 21. 

Conclusion of Intervention

Overall, I consider that the arrangements and their associated implementation for LC4 and LC21 for the areas inspected met with the required standards.  I did not identify any matter adversely affecting nuclear safety that required immediate regulatory action.