A SURVEY OF RN-222 IN-GROUND WATER FROM THE SHERWOOD SANDSTONE AQUIFER - BELFAST AND NEWTOWNARDS, NORTHERN-IRELAND

A study of radon-222 in ground water in Northern Ireland has revealed a range of concentrations from 5.8Bql(-1) to 36.6Bql(-1) (158pCil(-1) to 989 pCil(-1)). Radon-222 was measured using a portable degassing sy stem with scintillation cells and a portable radiation detector. Twent y-six samples were taken within the Sherwood Sandstone Aquifer underly ing Belfast and Newtownards. County Down. All samples collected were b elow the National Radiological Protection Board (NRPB) suggested limit of 100Bql(-1). Several hypotheses were considered for the distributio n pattern in the sandstone, the most probable being the presence of fa ults and lithological differences.