Document: NUREG-0800
Document ID: d4d35b7c-b4e5-4cb4-8dd9-1b7edddf0ad6
Document Type: srp
Title: CHEMICAL AND VOLUME CONTROL SYSTEM (PWR) (INCLUDING BORON
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070537.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.3.4
CFR Part: 
CFR Title: 

Content:
ipated operational occurrences. Portions of the CVCS system may be relied upon to provide negative reactivity addition by injection of boric acid to the reactor coolant system. Injection of sufficient negative reactivity by the reactivity control system assures that specified acceptable fuel design limits will not be exceeded. Meeting the requirements of GDC 29 enhances plant safety by assuring that the reactivity control aspects of the CVCS will have a high probability of injecting sufficient negative reactivity to prevent exceeding acceptable fuel design limits during anticipated operational occurrences, thereby preventing damage to the fuel matrix and cladding. 6. GDC 33 requires that a system be provided to supply reactor coolant makeup for protection against small breaks in the reactor coolant pressure boundary. The CVCS may be relied upon to provide charging and makeup in the event of small leakage from the reactor coolant pressure boundary and rupture of small piping or components that are part of the pressure boundary. Meeting the requirements of GDC 33 enhances plant safety by ensuring that the CVCS can provide sufficient makeup capacity to maintain the required RCS water inventory and prevent the violation of specified fuel design limits given a small break in the reactor coolant pressure. 7. GDC 35 requires that the ECCS safety function can be performed assuming a single component failure coincident with a loss of power. The CVCS may be relied upon to provide ECCS high head pumping capability necessary to ensure that emergency core cooling is provided during an accident. One of the functions of the CVCS is to transfer 9.3.4-9 DRAFT Rev. 3 - April 1996 sufficient heat from the core to prevent fuel and clad damage that could interfere with core cooling and to limit the cladding metal-water reaction to negligible amounts. Meeting the requirements of GDC 35 for the applicable portions of the CVCS enhances plant safety by ensuring that sufficient emergency