Document: NUREG-0800
Document ID: ebff6c02-bdd3-4751-9e36-9347caf05c8e
Document Type: srp
Title: and 2.4.6 are applicable to low water estimates due to the various phenomena discussed.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070258.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.4.5
CFR Part: 
CFR Title: 

Content:
na; and c. The importance of the safety functions to be performed. GDC 2 applies to this SRP section because the reviewer addresses natural hydrologic phenomenon that may reduce or limit the available cooling water supply and, in general terms, the amount of conservatism that must be used in assessing these natural phenomenon in order to determine the design bases for structures, systems, and components important to safety. Regulatory Guide 1.27 provides additional guidance for meeting these requirements. Meeting the requirements of GDC 2 provides assurance that an adequate water supply will be available for normal operations; anticipated operational occurrences; or safe shutdown of the plant after normal operations, anticipated operational occurrences, or emergency conditions.22 2. Compliance with GDC 44 requires that a system be provided to transfer heat from structures, systems, and components important to safety to an ultimate heat sink under normal operations, anticipated operational occurrences, and accident conditions. GDC 44 applies to this SRP section because the ultimate heat sink for the cooling water system consists of water sources that are subject to natural events, which in turn may reduce or limit the available cooling water supply. These natural events must be conservatively estimated to provide an adequate supply of cooling water from the ultimate heat sink to ensure that safety-related structures, systems, and components will be capable of performing their intended safety functions. Regulatory Guide 1.27 provides additional guidance for meeting these requirements. Meeting the requirements of GDC 44 provides assurance that the cooling water system will be capable of performing its intended safety functions by providing an adequate supply of cooling water to safety-related structures, systems, and components.23 3. Compliance with 10 CFR Part 100 requires, in part, that hydrologic characteristics be considered in the evaluation of a nuclear power