Leakage from biological shield cooling system in Pickering NGS A

Abstract

Over the past eight years. a number of leaks have developed in the Biological Shield Cooling (BSC) System of the Pickering NGS A reactors. The highest leak rate exists in Unit 4. The failure mechanism is not known. but corrosion and/or weld failure are suspected. This paper summarizes the concerns associated with the leaks and possible solutions. It should be noted that the BSC system is peculiar to Pickering A reactors only.