Document: NUREG-0800
Document ID: 96ddbfc8-7fd0-4a33-9fbe-144d653b6e9f
Document Type: srp
Title: REACTOR CORE ISOLATION COOLING SYSTEM (BWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070433.pdf
Revision Date: 2023-06
Chapter: 5
Section ID: 5.4.6
CFR Part: 
CFR Title: 

Content:
REVIEW RESPONSIBILITIES Primary - Reactor Systems Branch (RSBSRXB ) 1 Secondary - None I. AREAS OF REVIEW The reactor core isolation cooling (RCIC) system in a boiling water reactor (BWR) is a safety system which serves as a standby source of cooling water to provide a limited decay heat removal capability whenever the main feedwater system is isolated from the reactor vessel. Abnormal events which could cause such a situation to arise include an inadvertent isolation of all main steam lines, loss of condenser vacuum, pressure regulator failures, loss of feedwater, and the loss of offsite power. Each of these transients is analyzed in Chapter 15 of the applicant's safety analysis report (SAR). For each of these events, the high pressure part of the emergency core cooling system (ECCS) provides a backup function to the RCIC system. This review of the RCIC is performed to assure conformance with the requirements of General Design Criteria 4, 5, 29, 33, 34 and 54. In some plant designs, the RCIC system, in conjunction with the high pressure core flooder (HPCF) system, may be part of the emergency core cooling system. In such cases, the ECCS function of the RCIC system is reviewed under SRP Section 6.3. In addition, the RCIC system may provide decay heat removal necessary for coping with a 2 station blackout. The RCIC system capability to perform this function is reviewed as necessary to assure conformance with 10 CFR 50.63.3 The RCIC system consists of a steam-driven turbine-pump unit and associated valves and piping capable of delivering makeup water to the reactor vessel and supplying steam to and removing condensate from the RCIC steam turbine where applicable. Fluid removed from the reactor DRAFT Rev. 4 - April 1996 5.4.6-2 vessel following a shutdown from power operation is normally made up by the feedwater system, supplemented by inleakage from the control rod drive system. If the feedwater system is inoperable, the RCIC turbine-pump unit starts automatically or