Document: NUREG-0800
Document ID: 80e66b61-f0ed-49db-ba0b-ba2b7a7a0d52
Document Type: srp
Title: BASIC GEOLOGIC AND SEISMIC INFORMATION
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0423/ML042390206.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.1
CFR Part: 
CFR Title: 

Content:
is that all Seismic Category I excavations are required to be geologically mapped by the applicant and examined by the staff before backfill is placed or concrete poured. These activities were usually accomplished before the SER was made final. This procedure should continue in the future regarding sites that are licensed under the 10 CFR Part 50 two-phase construction permit and operating license procedure. However, under the 10 CFR Part 52 combined licensing procedure.(COL), as described above, geological features such as faults that are not discovered K ) until after the construction excavations are made and therefore after the license has been issued, will not have been assessed by the staff. Likewise, unanticipated engineering problems such as the presence of liquefiable materials, excessive settlement, heave, or groundwater flow that occur during or following construction will not have been evaluated by the staff. For these reasons, there must be a commitment in the site-specific portion of the SAR for a facility to (1) notify the staff immediately if previously unknown geologic features that could represent a hazard to the plant are encountered during excavation; (2) geologically map all excavations for Seismic Category I structures, as a minimum; and (3) notify the NRC staff when the excavations are open for examination and evaluation. The staff should conduct a followup site review when the excavations for the Seismic Category I structures are open to confirm the conclusions that the site parameters are within the envelope of the certified design. IV. EVALUATION FINDINGS On completion of the review of the geological and seismological aspects of the plant site and region, if the evaluation by the staff confirms that the applicant has met the requirements of applicable portions of References 1 and 2, and the guidance contained in References 3, 4, 5, and 6, the conclusion in the SER states that the information provided and investigations performed support the