Carbon-14 in Low-level Radioactive Waste From Two Nuclear Power Plants

The amount of 14C in low-level radioactive wastes is important for determining the future impacts of their disposal. New regulations in the Code of Federal Regulations, Title 10, Part 61 (10 CFR 61) require quantitation of 14C and other radionuclides in such wastes not amenable to measurement by gamma spectroscopy. Sampling was done of major waste streams at the Palisades pressurized water reactor (PWR) and the Big Rock Point boiling water reactor (BWR) to determine quantities of 14C in the waste streams for comparison with other reported studies. Analyses were performed by releasing all 14C constituents in the waste samples in the form of 14CO2 by chemical processing or by heating the samples in a tube furnace containing CuO2 catalyst and trapping the evolved gas in a liquid scintillator for counting. The largest amounts of 14C were found in the resins and filters used for reactor water cleanup, a result which is similar to those of the available studies. From these data, the annual amounts of 14C in wastes from nominal PWRs and BWRs were estimated to be 4.7 and 0.5 Ci/GW(e)-yr, respectively.