Summary

Until recently, commingled uranium mill tailings were believed to be of such low radiation that they were not considered harmful to the public. As a result, the tailings were often left in uncontrolled piles. Recent concern about the possible adverse effects of low-level radiation over long periods of time prompted the request that GAO determine whether federal assistance should be provided to active mills to clean up the mill tailings.

Cleaning up all of the commingled tailings would have the advantages of reducing a possible health hazard and taking another step toward resolving some of the problems of safely disposing of radioactive wastes. Offsetting these advantages, however, are some strong disadvantages. The cleanup costs could go as high as $315 million using current technology. Further, the cleanup program could be considered as an additional precedent for cleaning up other nuclear facilities, which would be a far more costly endeavor. This is extremely important because the question of who should pay for cleaning up nuclear facilities has not yet been fully considered, primarily because very little decommissioning of these facilities has been done to date. In the GAO view, the most significant factor in favor of providing federal assistance in cleaning up commingled tailings pertains to the Federal Government's role in creating the mill tailings situation.