Not later than February 3, 1991, the Secretary of Energy shall identify which single-shelled or double-shelled high-level nuclear waste tanks at the Hanford Nuclear Reservation, Richland, Washington, may have a serious potential for release of high-level waste due to uncontrolled increases in temperature or pressure. After completing such identification, the Secretary shall determine whether continuous monitoring is being carried out to detect a release or excessive temperature or pressure at each tank so identified. If such monitoring is not being carried out, as soon as practicable the Secretary shall install such monitoring, but only if a type of monitoring that does not itself increase the danger of a release can be installed.

Not later than March 5, 1991, the Secretary of Energy shall develop action plans to respond to excessive temperature or pressure or a release from any tank identified under subsection (a).

Beginning March 5, 1991, no additional high-level nuclear waste (except for small amounts removed and returned to a tank for analysis) may be added to a tank identified under subsection (a) unless the Secretary determines that no safer alternative than adding such waste to the tank currently exists or that the tank does not pose a serious potential for release of high-level nuclear waste.