The purpose of the Conceptual Basis for Design is to provide a control document that establishes the basis for executing the conceptual design of the Integral Monitored Retrievable Storage (MRS) Facility. This conceptual design shall provide the basis for preparation of a proposal to Congress by the DOE for construction of one or more MRS Facilities for the storage of spent nuclear fuel, high-level radioactive waste, and transuranic (TRU) waste.