The hydrogeochemistry of Norwegian bedrock groundwater - selected parameters (pH,F,Rn,U,Th,B,Na,Ca) in samples from Vestfold and Hordaland, Norway

Abstract

Over 300 samples of bedrock groundwater from Hordaland county and the Oslo rift lithologies of Vestfold county have been collected and analysed for radon and fluoride. A selection of 150 samples have been analysed for a large range of major and trace parameters by ICP-AES and ICP-MS techniques at two different laboratories. 53% of all waters contravene recognised drinking water limits for at least one of the following parameters: pH,U,Rn,F and Na. The majority of these contraventions are identified in the Hordaland area (64% contravention) with a rete of only 28% contravention in Vestfold. Maximum levels of 2mg\/L, 6840Bq\/L and 9.2 mg\/L were recorded for U, Rn and F, respectively. These findings have implications for water resource policy in a country where ground- water is actively being promoted as an alternative to vulnerable surface water sources. Bedrock groundwater may still be considered a viable resource provided that effort is invested in compiling hydrochemical hazard maps for bedrock groundwater and provided that consumers and water suppliers are willing to accept the need for a degree of water treatment in some cases.