Document: NRC Regulatory Guide
Document ID: 8b2255d1-47a9-4dfe-ba41-568c561a89ee
Document Type: regulatory_guide
Title: Inspection of Water-Control Structures Associated with Nuclear Power Plants + HISTORY – HISTORY 01/2015 – DG-1245 , Proposed Revision 2 (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1325/ML13255A435.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.127
CFR Part: 
CFR Title: 

Content:
n for Nuclear Power Plants” (Ref. 19) and RG 1.27, “Ultimate Heat Sink for Nuclear Power Plants” (Ref. 20). The evaluation should consider constraints on water control such as blocked entrances, restrictions on the operation of spillway and outlet works, inadequate energy dissipators, restrictive channel conditions, and reduction in reservoir capacity by sedimentation and other factors. b. Sustainability Assessments Sustainability assessments should use in-situ properties of the structures, including foundation and pertinent geologic, geotechnical and seismic information, to determine the existence of changes to or the continuation of conditions that are hazardous or that might develop into safety hazards over time and to formulate recommendations pertaining to the need for additional investigations, analyses, or remedial measures. The probability of soil liquefaction after a seismic event is another important aspect of the stability of embankments that should be assessed. RGs 1.208 and 3.11 as well as FEMA Publication 93 should be used for conducting post-earthquake stability assessments using the residual strength of the soils composing the embankments. 7. Operating Experience Inspection and monitoring programs of water-control structures should be established commensurate with safety, and should also take into account industry wide operating experience. 8. Special Provisions for Dams In addition to the guidance contained herein, instrumentation, monitoring, and inspection of dams (as defined in the Federal Guidelines for Dam Safety) should meet the guidance in the Federal Guidelines for Dam Safety. This should include incorporating the appropriate design provisions to conduct the inspection and monitoring programs. 9. Frequency of Inspections The inspection intervals discussed below should be used in developing projected inspection schedules. These intervals in no way preclude more frequent inspections if deemed necessary or less frequent inspections (with