Document: NUREG-0800
Document ID: 853719df-a6ea-408b-8d43-5956155abc38
Document Type: srp
Title: and 8.3.2.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1007/ML100740246.pdf
Revision Date: 2023-06
Chapter: 8
Section ID: 8.3.1
CFR Part: 
CFR Title: 

Content:
e risk assessment before performing Agrid-risk-sensitive@ maintenance activities (such as surveillances, post-maintenance testing, and preventive and corrective maintenance). Such activities are those which could increase risk under existing or imminent degraded grid reliability conditions, including (1) conditions that could increase the likelihood of a plant trip, (2) conditions that could increase the likelihood of a LOOP or SBO, and (3) conditions that could have an impact on the plant=s ability to cope with a LOOP or SBO, such as out-of-service risk-significant equipment (for example, an EDG, a battery, a steam-driven pump, or an alternate ac power source). 8.2-15 Revision 5 - May 2010 III. REVIEW PROCEDURES The reviewer will select material from the procedures described below, as may be appropriate for a particular case. These review procedures are based on the identified SRP acceptance criteria. For deviations from these acceptance criteria, the staff should review the applicant=s evaluation of how the proposed alternatives provide an acceptable method of complying with the relevant NRC requirements identified in Subsection II. 1. To verify that the requirements of GDC 17 are satisfied, the following review steps should be taken: A. The electrical drawings should be examined to ensure that at least two separate circuits from the transmission network to the onsite power distribution system buses are provided (a single switchyard may be common to these paths). For evolutionary light water reactor design applications, the design should include at least one offsite circuit to each redundant safety division that is supplied directly from an offsite power source with no intervening non-safety buses, thereby permitting the offsite source to supply power for safety buses in the event the non-safety bus(es) fail. The design should also include an alternate power source to non-safety loads, unless it is demonstrated that existing design margins will result in