Unusual levels of radioactivity were detected at a storm water collection tank serving a number of Active Plants. The radioactivity was traced to a spillage of active liquor arising from active liquor transfers. Heavy rain had washed the active liquor spillage into the storm water drain and contaminated roadway, gutters and building environments. About 5 GBq beta and 100 MBq alpha was found on the ground, etc.
Personnel contamination and radiation exposure was not significant.
Discharges to the environment were well within the authorised limits.
This has been rated at Level 2 because of the quantity that arose in areas not expected by design. (100s GBq Ru 106 or 10s MBq plutonium, Clarifications of Issues raised (INES User's Manual))
Event date: Mon, 03-02-1997