[en] A new type of boiling-water reactor (BWR) has been conceived - the Process-Inherent, Ultimate-Safety, Boiling-Water Reactor (PIUS BWR). The proposed design described in this report extends the PIUS design philosophy from pressurized-water reactors (PWRs) to BWRs. In a PIUS BWR, safety systems are passive, with no active components. The reactor core and nonnuclear portion of the plant are similar to current BWR designs, but a special, prestressed concrete reactor vessel (PCRV) with a unique internal design replaces the conventional pressure vessel, emergency core cooling systems, containment shell, spent-fuel storage ponds, diesel generators, and most other components of the nuclear island