Low specific activity deposits containing 226Ra, 228Ra and their daughter isotopes is a well-known problem in the petroleum industry. It is estimated that installations in the Norwegian sector of the North Sea will generate from 50 to 75 tons of scale and sludge annually.
A simple method for on-site classification of LSA scale has been developed. Classification of the sludge from the Brent Spar revealed that only a small fraction of the total amount of sludge exceeded the exemption level. Sludge classified to be below the free classification limit was incinerated with surveillance of activity levels in the ash and effluents.