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:
removed by circulating drilling fluid. Undisturbed samples in stiff, hard, brittle, cohesive soils and sands with cementation, and in soft rock. Effective in sampling alternating hard and soft layers. Representative samples in soft-to-medium cohesive soils and silts. Disturbed samples may be obtained in cohesionless materials with variable success. Frequently ineffective in cohesionless soils. Split-barrel or split-spoon sampler Split-barrel tube is driven into soil by blows of falling ram. Sampling is carried out in conjunction with Standard Penetration Test. Representative samples in soils other than coarse-grained soils. Samples are disturbed and not suitable for tests of physical properties. Auger sampling Auger drill used to advance hole is withdrawn at intervals for recovery of soil samples from auger flights. Determine boundaries of soil layers and obtain samples of soil classification. Samples are not suitable for physical property or density tests. Large errors in locating strata boundaries may occur without close attention to details of procedure. In some soils, particle breakdown by auger or sorting effects may result in errors in determining gradation. DG-1392, Appendix C, Page C-3 APPENDIX C, Cont’d. METHOD PROCEDURE APPLICABILITY LIMITATIONS Rotary core barrel Hole is advanced by core bit while core sample is retained within core barrel or within stationary inner tube. Cuttings removed by drilling fluid. Core samples in competent rock and hard soils with single tube core barrel. Core samples in poor or broken rock may be obtainable with double tube core barrel with bottom discharge bit. Because recovery is poorest in zones of weakness, samples generally fail to yield positive information on soft seams, joints, or other defects in rocks. Denison sampler Hole is advanced and reamed by core drill while sample is retained in nonrotating inner core barrel with core catcher. Cuttings removed by circulating drilling fluid. Undisturbed samples in