Office for Nuclear Regulation

MSC11 - Manufacturing Assurance - Start of Procurement - Safety Chilled Water System

Executive summary

Purpose of Intervention

The purpose of this intervention was to assess NNB Generation Company (HPC) Limited’s (NNB GenCo) implementation of its arrangements for carrying out a project gateway review on equipment contract package prior to the release of the start of design and procurement hold point for that equipment.

Interventions Carried Out by ONR

ONR carried out a Licence Condition 17 ‘Management Systems’ intervention related to the release of the start of design and procurement hold point for the Safety Chilled Water System (DEL) chillers that provide chilled water to a number of heating, ventilation and air conditioning systems. Licence Condition 17 requires the licensee, within its management systems, to make and implement adequate quality management arrangements for all activities that may affect safety. This includes procurement, design, construction, manufacture and commissioning.

The intervention was carried out by observing the gateway review via Skype after which a follow up meeting was held to discuss observations and raise questions.

Explanation of Judgement if Safety System Not Judged to be Adequate

Not applicable.

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

The review was conducted in a professional manner with an atmosphere that encouraged open discussion of technical and project matters. The NNB GenCo Project Manager was not seen to be exerting undue pressure on the other attendees to approve the items on the review checklist. The attendees appeared to be knowledgeable in their respective areas and understood the objectives of the review.

Prior to the intervention ONR was provided with the partially completed project gateway checklist which provided a framework for conducting gateway reviews prior to commencing various phases of a contract. The checklist was then completed through the course of the review to capture evidence and any actions that needed to be addressed prior to release of the gateway. I am satisfied that the review was conducted in line with NNB GenCo’s written arrangements for readiness gateway reviews.

Consideration was given to the design maturity of the chillers along with the status of various open points; however the design / safety case attendees did not always convey the full extent of the risk to the chillers project associated with the open points. This was discussed following the review and I do not consider that it needs any further regulatory action.

The gateway checklist includes criteria addressing the assessment findings from the EPR Generic Design Assessment and ONR interventions. I am satisfied that these criteria were adequately examined during the review and that the conclusions reached were appropriate with respect to the design and procurement gateway.

The NNB GenCo attendees at the gateway review demonstrated an awareness of operational experience from the wider Hinkley Point C (HPC) project, for example lifetime quality records management and use of paint treatments compatible with temporary outside storage. It is understood that appropriate measures have been taken to include relevant learning in the chillers contract.
NNB GenCo informed ONR that it had been working closely with the preferred bidder for the chillers via an Early Contractor Involvement contract. This early engagement has allowed NNB GenCo to reduce risks by reviewing and closing numerous open points prior to the gateway review. 

I am satisfied that adequate consideration was given to the various items of the checklist which make up the gateway review. I was assured to see that checklist items were rejected if the review participants did not agree that sufficient evidence had been provided to warrant acceptance. As such the chairperson concluded that the DEL chillers project was not ready to release the start of design and procurement hold point. I understand that further work and another review will take place to review the evidence against the rejected items before the start of design and procurement hold point is released.

Conclusion of Intervention

Overall, I am satisfied that NNB GenCo’s implementation of its arrangements for the release of the start of design and procurement hold point was adequate. Observing the review provided assurance that the start of design and procurement hold point would not be released for the DEL chillers until the identified actions have been closed and the requirements of the review checklist have been met.

Based on the observations, discussions and evidence from NNB GenCo leading up to and during the review, I consider NNB GenCo’s implementation of its LC17 arrangements for the review and release of start of the design and procurement hold point for the DEL chillers to be GREEN (no formal action required).