Blending as the best compliance option for the management of radioactivity in drinking water supplied from the deep sandstone aquifer in Southern Jordan
This paper describes management options and interventions taken by the Government of Jordan to ensure that the quality of drinking water supplied to consumers via the Disi Water Conveyance Project (DWCP) meets Jordanian drinking water standards and WHO guidelines for drinking water quality in respect of their radiological composition. Results from an initial survey of radioactivity present in water abstracted from each of the 55 wells (which comprise the operational well field) indicated an average radiological dose of 0.8 milliSieverts per year (mSv/y) would be accrued by members of the population if consuming water directly from the well head. During full scale operation, the estimated accrued dose from the well field as a whole decreased to an average of 0.7 mSv/y which was still approximately 1.4 times the Jordanian reference radiological limit for drinking water (0.5 mSv/y). Following assessment of treatment options by relevant health and water authorities, blending prior to distribution into the consumer network was identified as the most practicable remedial option. Results from monthly sampling undertaken after inline blending support the adoption of this approach, and indicate a reduction in the committed effective dose to 0.4 mSv/y, which is compliant with Jordanian standards.