LLW reduction methods employed at de Pont/NEN research products

Recent and changing low-level radioactive waste (LLW) disposal regulations and limitations have made it an economic necessity to implement programs to minimize radwaste. Du Pont Biomedical Department's NEN Research Products plant in Boston, Massachusetts, produces radioactive products for research labeled with tritium, 14C, 32P, and 35S. An extensive radwaste minimization effort has been established with very significant reduction results without compromise in radiation safety. The disposal of radwaste is a complicated, highly regulated business. The economic factors include a combination of cost per unit volume, cost per unit volume, cost per unit radioactivity, and cost effective/ineffective packaging methods and handling procedures. The first two cost factors are uncontrollable. Methods described in this paper, however, have controlled the third cost factor to offset to some extent the increases of the first two factors. Tritium-containing products comprise the largest category of products produced. A high-integrity package has been put into use. A tritium gas recycling apparatus has been developed for purification of high-level waste tritium gas. Carbon-14 waste has been reduced by careful review of synthesis procedures. An extensive program to hold-for-decay for the waste containing 32P and 35S has been established. A computer program has been developed whereby all waste generated is tracked from cradle-to-grave. Therefore by various methods, some simple and some complex, very significant low-level waste reductions have been achieved to control rapidly increasing disposal costs