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:
ty undisturbed samples. DG-1392, Page 14 4.4 Borings and Exploratory Excavations Field operations conducted at the site should be supervised by experienced personnel familiar with site operations, and systematic standards of practice should be followed. Procedures and equipment used to carry out field operations, including necessary calibrations, and all conditions encountered in various phases of the investigations should be documented. Personnel who are experienced and thoroughly familiar with sampling and testing procedures should inspect and document sampling results and transfer samples from the field to storage or laboratory facilities with a properly executed chain-of-custody record. The complexity of geologic conditions and foundation requirements should be considered in choosing the distribution, number, and depth of borings and other excavations at the site. The investigative efforts should be greatest at the locations of safety-related structures and might vary in density and scope in other areas according to spatial and geologic relationships to the specific site. Excavation trenches across faults or shear zones might be required to determine the age of last movement on these tectonic features to better assess the potential impact of the features on site safety. At least one continuously sampled boring should be drilled for each safety-related structure, and the boring should extend to a depth sufficient for defining the geologic and hydrogeologic characteristics of the subsurface materials that will influence the stability and suitability of the safety-related structures. NUREG/CR-5738, “Field Investigations for Foundations of Nuclear Power Plants,” issued November 1999, describes procedures for borings and exploratory excavations. Appendix C to this guide reproduces a table from NUREG/CR-5738 showing widely used techniques for subsurface investigations and describing the applicability and limitations of the techniques. Appendix D to this RG