Low-level radioactive waste has been produced since the early 1940's. Most of it has been buried in shallow pits at 11 existing sites. Several of the existing sites have performed poorly. Inability to control flow of surface and ground water into and out of disposal pits has been the most important problem. Lack of attention to design of earthen covers over the waste and improper emplacement of the waste in the pits have also contributed to poor performance. Several steps are recommended for improving disposal practices: (1) Waste settlement can be minimized by stacking wastes neatly into pits rather than dumping them randomly; (2) the earthen cover can be made to perform better by making it thicker and by maintaining it properly; and (3) groundwater contamination can be minimized by siting disposal facilities at locations with favorable geohydrologic characteristics. In addition, improved designs are needed for earthen covers, and technology for predicting ground water contamination in the saturated/unsaturated soils that underlie the waste also needs improvement.
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