Document: NUREG-0800
Document ID: c5da9adb-ab27-4695-99d7-12432175e5c4
Document Type: srp
Title: and Reference 3).
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0707/ML070730464.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.2
CFR Part: 
CFR Title: 

Content:
te vicinity, site area, and site location as necessary to examine soil and rock samples from core borings and test pits and geologic features in trenches and excavations for plant facilities, if these information sources exist. Since geologic features (e.g., faults, paleoliquefaction features indicative of seismically-induced ground motions, and solution cavities) or geologic materials (e.g., soil or rock zones that may result in unanticipated engineering concerns due to liquefaction, heave, excessive settlement, or groundwater flow during or after construction) which have the potential to adversely impact site safety may be discovered in plant excavations or during other field investigations, this reconnaissance is deemed necessary in light of requirements and procedures specified in Subpart C of 10 CFR Part 52 which allows for a COL (i.e., a combined CP and OL) as an alternative to the two-step licensing process previously defined in 10 CFR Part 50 which includes a CP (Step 1) separate from an OL (Step 2). Under the COL approach defined in 10 CFR Part 52, the Safety Evaluation Report (SER) will have been written by the staff and a license granted to the applicant before plant construction excavations and geologic mapping of the excavations begin. Therefore, the geologic reconnaissance performed by the staff notwithstanding, geologic features and potential engineering concerns discovered in plant excavations of applicants granted a COL may not have been evaluated by the staff. To alleviate potential problems, clear statements must be provided in the site-specific portion of the COL application that the applicant commits to (1) notifying the staff immediately if previously unknown geologic features that could represent a safety hazard to the plant are discovered in the excavations; (2) at a minimum, undertaking detailed geologic mapping of walls and floors of all excavations for Seismic Category I facilities; and (3) notifying NRC staff when the excavations and