[en] Numerous legal, regulatory, and technical problems and uncertainties are hampering disposal of nuclear and coal fuel cycle wastes. Although federal agencies are working on these problems, progress has been slow and many uncertainties still need to be resolved. While available information indicates that coal waste disposal costs are roughly three times higher than nuclear waste disposal costs, this cost comparison must be viewed with caution. Accurate disposal costs are not readily available, particularly for the nuclear fuel cycle, because some nuclear wastes have never been disposed of and actual disposal costs are unknown