This was a planned visit in pursuance of ONR’s plan of compliance inspection for Chapelcross.
In September, the site inspector from the Scottish Environment Protection Agency (SEPA) and I carried out an inspection of the storage of waste. This waste arose from the Chapelcross Processing Plant, which until 2005 extracted and purified tritium generated in Chapelcross’s reactors. The objective of the inspection was to decide whether the waste containers and the store fulfil one of their safety functions, namely to protect the public and workers from the residual tritium in the waste. At this visit I completed that inspection.
In other inspections I examined the licensee’s compliance with licence conditions covering emergency arrangements and the control and supervision of operations.
The new Parent Body Organisation that owns the licensee has instituted a review of the processes by which its ten Magnox Ltd sites will manage intermediate level waste, the largest hazard now remaining at Chapelcross and those other sites from which fuel has been removed. I had meetings to discuss this review, and to tell the licensee how ONR, in conjunction with SEPA, intends to regulate the associated waste management projects.
In these and other discussions the outcomes of actions previously placed were reviewed, and the actions closed where possible; new actions were also placed.
I concluded that the licensee’s safety case for the containment of tritium in the store was adequate, as were its arrangements for preventing and detecting leaks. Though the operating and maintenance instructions for the store, and the records of that maintenance, were generally adequate I found some deficiencies in them.
I found adequate compliance with the licence conditions covering emergency arrangements and the control and supervision of operations.
Overall, I concluded that on the evidence examined the store is achieving its safety function of protecting workers and the public from tritium.
I have reached this conclusion despite increases in aerial discharges of tritium from the store during the middle of 2014. Discharges have been and remain of negligible significance to health (and the environment). They are a small fraction of the site’s total aerial discharge of tritium, and have recently decreased significantly. Nevertheless, it is desirable that both Magnox Ltd and the regulators continue to seek an explanation of the increases. Magnox Ltd’s investigations have been thorough but are still inconclusive. If evidence of a cause emerges, or if there are further marked increases, then I will of course reassess the opinion expressed above.
I have required the licensee to remedy the deficiencies mentioned in Paragraph 6.
I found no issues that significantly affect nuclear safety, or that require me to take further regulatory action.