Document: NUREG-0800
Document ID: 97120913-d26f-4324-ab62-22f3f5b73925
Document Type: srp
Title: and 8.3.2.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0636/ML063600410.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.1
CFR Part: 
CFR Title: 

Content:
C documents (e.g., References 22, 24, 25, 29, 30, and 43) are useful in the review of the adequacy and reliability of the plant’s interface with the offsite power grid and communication with offsite transmission system operating authorities. K. The reviewer should verify that adequate procedures, administrative controls, and protocols are in place to ensure that no modifications to the offsite power system circuits credited for satisfying GDC 17 are implemented by offsite transmission system operating authorities, responsible for maintenance, modification, and operation of the offsite transmission grid, without the performance of a proper safety evaluation. The safety evaluation of 8.2-20 Revision 4 - March 2007 transmission system modifications is required to ensure that the transmission grid configuration, stability, and capability remain within the assumptions of the plant safety analyses. Further information on potential unreviewed safety questions associated with modifications to offsite transmission circuits can be found in Reference 45. In addition, the reviewer should verify that grid reliability evaluations are performed for maintenance or modifications to the offsite power system, as part of the maintenance risk assessment required by 10 CFR 50.65 before performing “grid-risk-sensitive” maintenance activities. L. Operating experience has shown that undetected degradation of underground electric cables due to protracted exposure to wetted environments or submergence in water or resulting from pre-existing manufacturing defects could result in multiple equipment failures. Underground or inaccessible power and control cable runs that are susceptible to protracted exposure to wetted environments or submergence as a result of tidal, seasonal, or weather event water intrusion are reviewed. Cables from independent power sources or different safety divisions could be affected by the same condition. Underground or inaccessible power cables connecting offsite