Document: NRC Regulatory Guide
Document ID: a094549d-8685-4dad-b90f-c28c7d279a53
Document Type: regulatory_guide
Title: Geologic and Geotechnical Site Characterization Investigations for Nuclear Power Plants + HISTORY – HISTORY 08/2021 – DG-1392 , Proposed Revision 3 07/2014 – Periodic Review of Revision 2 – Reviewed with no issues identified 02/2001 – DG-1101 , Proposed Revision 2 (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2119/ML21194A176.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.132
CFR Part: 
CFR Title: 

Content:
orrespond to residual angle of friction). What are probable previous and present ground water levels? Check highway and railway cuts and deep excavations, quarries, and steep slopes. Do trees slope in an unnatural direction? Faults and faulting; past seismic activity Of decisive importance in seismic evaluations; age of the most recent fault movement may determine seismic design earthquake magnitude and may be indicative of high state of stress that could result in foundation heave or overstress in underground works. Determine existence of known faults and fault history from available information. Check potential fault traces identified on remote sensing imagery, Google Earth, and light detection and ranging (LiDAR). Compare geologic and seismicity maps. Verify presence of fault at site, if possible, from surface evidence. Examine and consider characteristics of geologically young alluvial deposits and river terraces in the site vicinity. Are lineaments or possible fault traces apparent from regional aerial imagery? Examine existing boring logs for evidence of faulting from offset of strata and indications of breccia and shear zones. Make field check of geologic maps, structures, cellars, chimneys, roads, fences, pipelines, known faults, caves, inclination of trees, and offset in fence lines. Joints and fractures High concentration of joints indicates weakness of bedrock and high strain. Study satellite images, aerial photos, and LiDAR and define all available lineaments and their relationship, if possible. Investigate orientation and density of joints. Assess any cross-cutting relationships between joint sets and estimate age of jointing. Are the joint sets related to denudation and unloading or are they tectonically formed? What is the current orientation of stress in the crust? DG-1392, Appendix A, Page A-2 APPENDIX A, Cont’d. GEOLOGIC FEATURE OR CONDITION INFLUENCE ON PROJECT OFFICE STUDIES FIELD OBSERVATIONS QUESTIONS TO ANSWER Stress relief cracking and