The Scottish Environment Protection Agency (SEPA) received notification from the Chapelcross site that water had ingressed into a bulk item of solid radioactive waste that was being stored in accordance with standard procedures.
A report submitted to the Chapelcross Site Stakeholders’ Group last Friday explained that the event is currently being investigated at site level, and the details will also be the subject of a SEPA inspection.
Site closure director John Grierson told the meeting the incident was believed to have occurred when an item of metalwork was temporarily stored outside.
It comes just a few months after Chapelcross was issued with a SEPA warning letter in December, following a similar incident at the site in March last year.
On that occasion a small amount of contaminated water was found inside pipe work removed from the Chapelcross heat exchanger, which had been shipped to Sweden for treatment.
This event led to Chapelcross being graded as “good” for its compliance with its radioactive substances registration and non-nuclear authorisation (RSA) in 2018.
The report to the SSG said: “This means that the site has been assessed as not quite fully compliant with their authorisation conditions and highlights an area of improvement to achieve “excellent”.
“The identified non compliance was associated with the disposal of a bulk item of solid low level waste which contained contaminated water.
“SEPA would reiterate that there was no radiological harm to the public or the environment as a result of the incident.”
Mr Grierson also told the meeting that, in his opinion, “good was not good enough”, and that the site would be striving to achieve an “excellent” grading.
He also explained that the latest contamination incident was reported to SEPA at the time and is being investigated.
Meanwhile, the Office for Nuclear Regulation (ONR) carried out four Licence Condition Compliance Inspections at Chapelcross and judged that no formal action was required.