Document: NUREG-0800
Document ID: 2cb61281-91f4-400a-8eda-41e187e51d77
Document Type: srp
Title: AUXILIARY FEEDWATER SYSTEM (PWR)
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0705/ML070570007.pdf
Revision Date: 2023-06
Chapter: 10
Section ID: 10.4.9
CFR Part: 
CFR Title: 

Content:
REVIEW RESPONSIBILITIES Primary - Organization responsible for the review of cooling water systems Secondary - None I. AREAS OF REVIEW The auxiliary feedwater system (AFWS) normally operates during startup, hot standby and shutdown as the feedwater system for pressurized water reactor (PWR) plants. With a seismic Category I water source, it also functions as an emergency system for heat removal from the primary system when the main feedwater system is not available for emergency conditions including small-break loss-of-coolant accident (LOCA) cases. The AFWS operates over a time period sufficient either to hold the plant at hot standby for several hours or to cool down the primary system, at a rate not exceeding limits specified in technical specifications, to temperature and pressure levels at which the low pressure decay heat removal system can operate. The review verifies compliance with General Design Criteria (GDC) 2, 4, 5, 19, 34, 44, 45 and 46. The AFWS also may remove decay heat to withstand or cope with a station blackout. If so, the review also includes verification of compliance with the requirements of 10 CFR 50.63 as they relate to the AFWS design. The AFWS is reviewed from the interfaces with the condensate storage tank (normal operation) and the seismic Category I water supply, includes all components of both flow paths (e.g., piping, controls, sensors, valves, pumps, etc.), and terminates at the connections with the steam generators. All inter-connections and cross-connections are included in the review. 10.4.9-2 Revision 3 - March 2007 The review also includes AFWS components (e.g., pumps, valves, and piping) for their functional performance as affected by adverse environmental conditions, anticipated operational occurrences, and accident conditions (e.g., small breaks in the primary system or the loss of offsite power). The system is reviewed for whether a single malfunction, a failure of a component, or the loss of a cooling source does not reduce