Contra-expertise on the determination of radioactivity of waste water and ventilation air of NRG at Petten. Period 2007
Contra-expertise op bepalingen van radioactiviteit van afvalwater en ventilatielucht van NRG. Periode 2007
09 July 2012, PDF |
25 pages |
Kwakman PJM, Overwater RMW
RIVM Report 610330120
Within the framework of a monitoring programme, the RIVM measures the release of radioactivity into waste water and atmosphere of the Nuclear Research and Consultancy Group (NRG) at Petten. Measurements are carried out eight times per year. This form of counter-expertise is aimed at verifying and supporting the reliability of the analyses carried out by NRG. In 2007, the two different sets of measurements in waste water are generally in agreement. The few discrepancies that were observed in 2007 concern the gross-beta data in waste water; RIVM reports considerably lower gross-beta data than NRG does. This is partly explained by the presence of short-lived betaemitters in waste water of NRG, and partly because of differences in the analytical methods applied by NRG and RIVM.
In samples taken from ventilation air, RIVM determined in some cases an activity concentration below the detection limit of NRG. NRG measures the filters mainly for screening purposes and, therefore, applies a much shorter measuring time than RIVM.
The RIVM analyzed eight waste water samples and eight samples of ventilation air taken by NRG at various time points dispersed throughout 2007. The analyses were carried out on behalf of the Department of Nuclear Safety, Security and Safeguards of the Dutch Ministry of Housing, Spatial Planning and the Environment (VROM).