Document: NUREG-0800
Document ID: 500d6b1d-6d0c-45db-abba-a953c0faa92a
Document Type: srp
Title: STABILITY OF SUBSURFACE MATERIALS AND FOUNDATIONS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1006/ML100610449.pdf
Revision Date: 2023-06
Chapter: 2
Section ID: 2.5.4
CFR Part: 
CFR Title: 

Content:
tion has been carried out and to determine whether or not the interpretations made by the investigators are valid and the foundation design assumptions contain adequate margins of safety. 4. 2.5.4.4 - Geophysical Surveys. In meeting the requirements of 10 CFR 100.23, the presentation of the dynamic characteristics of soil or rock is acceptable if geophysical investigations have been performed at the site and the results obtained there from are presented in detail. Completeness of the presentation is judged by whether or not the exploratory techniques used by the applicant yield unambiguous and useful information, whether they represent state-of-the-art exploration methods (Ref. 10), and whether the applicant's interpretations are supported by adequate field records in the SAR. Multiple measurements of dynamic properties should be incorporated to capture uncertainty in the primary parameters controlling site response behavior. See also Subsection 2.5.2.3. Staff evaluation consists of a detailed review of all geophysical explorations conducted at the site, including seismic refraction, reflection, and in-hole surveys and magnetic and gravity surveys. Consultant expertise regarding specific techniques may be drawn upon in this review. Logs of core borings, trenches, and test pits are reviewed and compared with data from the seismic surveys and other geophysical explorations. Results must be consistent or additional investigations are required, or the applicant must use the most conservative values. The staff will visit the site to examine the walls and floors of excavations at an appropriate time after licensing to confirm conditions as mapped in the open excavations with interpretations and assumptions derived during the investigation program. 5. 2.5.4.5 - Excavation and Backfill. In meeting the requirements of 10 CFR Part 50, the presentation of the data concerning excavation, backfill, and earthwork analyses is acceptable if: A. The sources and quantities of