Summary of findings on evaluation of aqueous degreasers versus chlorinated solvents at the Paducah Gaseous Diffusion Plant

Spent trichloroethylene (TCE), 1,1,1-trichloroethane (TC-ane), and sludge are generated mainly as a result of vapor degreasing operations at the Paducah Gaseous Diffusion Plant (PGDP). Additionally, small quantities of spent chlorinated solvents are generated as a result of small parts cleanup. These wastes are listed hazardous wastes under Resource Conservation and Recovery Act (RCRA) regulations (40 CFR 261) and account for greater than 50% of the hazardous waste generated at PGDP. Additionally, some of the solvents become contaminated with uranium which classifies them as mixed waste for which no disposal method is currently available. TCE and TC-ane are both associated with potential health hazards and are subject to a number of environmental regulations. Due to health and environmental concerns and the desire to minimize mixed and hazardous waste generation, a study was initiated to identify nonchlorinated, less toxic degreasers, perform laboratory testing of the most promising alternatives, and initiate field testing to determine if alternate degreasers present operational problems. The degreaser that cleaned and protected metal surfaces best was an all-purpose, water-based, hard surface cleaner consisting of biodegradable synthetic detergents, inorganic builders, and a glycol ether solvent. Additionally, this product was free-rinsing and did not leave any contaminants that would react with commonly used process gases. This product is recommended as a replacement for chlorinated solvents for many degreasing operations at PGDP