Document: NUREG-0800
Document ID: 577b52cf-90e2-467e-8165-a1ce02957947
Document Type: srp
Title: REACTOR WATER CLEANUP SYSTEM (BWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070438.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.8
CFR Part: 
CFR Title: 

Content:
is reason, the portion of the RWCS extending from the reactor vessel and recirculation loops to the outermost drywell isolation valves should be designed to seismic Category I and Quality Group A. The remainder of the system need not be seismic Category I and should be designed to Quality Group C. The precoating unit for demineralizers need not be designed to Quality Group C and need not be seismic Category I. Meeting the requirements of GDC 1 provides assurance that a failure of the RWCS will not occur, thus avoiding the potential for a loss-of-coolant accident or release of radioactive materials outside the containment structure.56 B. Compliance with GDC 2 requires that nuclear power plant structures, systems, and components important to safety be designed to withstand the effects of natural phenomena such as earthquake, tornado, hurricane, flood, tsunami, and seiche without loss of capability to perform their safety functions. GDC 2 applies to the RWCS because the system carries reactor water outside the containment structure and contains radioactive material. Failure of a system component as the result of a natural phenomenon could result in release of reactor water until the containment isolation valves close and in release of radioactive materials outside the containment structure. DRAFT Rev. 3 - April 1996 5.4.8-8 Meeting the requirements of GDC 2 provides assurance that a failure of the RWCS will not occur, thus decreasing the potential for release of reactor coolant or other radioactive materials outside the containment structure.57 C. Compliance with GDC 14 requires that the reactor coolant pressure boundary shall be designed, fabricated, erected, and tested to ensure extremely low probability of abnormal leakage, rapidly propagating failure, and gross rupture. GDC 14 applies because the materials used in the reactor coolant system require careful control. Thus, reactor cooling water chemistry and levels of impurities must be monitored to avoid