The NOx system in nuclear waste. 1998 annual progress report

'The objective of this project is to assist EM sites in the resolution of outstanding safety issues involved in the temporary storage of high-level waste (HLW) in large tanks. To achieve this objective, mechanisms of the radiolytic and radiolytically induced processes that occur in the waste are quantitatively studied. The information is incorporated into a computer modeling of the tanks chemistry under various scenarios and the predicted results are rapidly conveyed to the site operators. This report summarizes the technical achievements of a 3-year project that is now in its 2nd year of operation. The project is a collaborative effort between the ANL and PNNL and is strongly coupled to another EMSP project (``Interfacial Radiolysis Effects in Tank Waste Speciation'''' PI: T. Orlando, PNNL) and to the safety programs at the Hanford site (``Organic Tanks Safety Program: Waste Aging Studies'''', PI D. Camaioni, PNNL). Information from the project is also shared directly with Westinghouse Savannah River personnel. In general, the basic studies are performed at ANL and PNNL and the information is continuously shared with Tanks Safety Programs. To further facilitate the exchange of information and the immediate incorporation of results into operations, the authors conducted at least twice a year coordination meetings at the various laboratories where the site operators (e.g. from DE and SH, Numatec, WSRC, etc.) participate, both to present their needs and to obtain updated information.