Document: NRC Regulatory Guide
Document ID: 01fb3132-b05a-41a0-ab81-466a6fb6f4d3
Document Type: regulatory_guide
Title: Preparation of Environmental Reports for Nuclear Power Plant License Renewal Applications (Rev. 1)
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML0916/ML091620409.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.2S1
CFR Part: 
CFR Title: 

Content:
lysis Content If the plant pumps more than an annual average of 100 gpm (6 L/s), the applicant should provide the following information and analyses to enable the NRC staff to assess the magnitude and significance of potential groundwater use conflicts during operation: • Describe all groundwater aquifers potentially impacted by operation of onsite wells, including approximate areal extent, thickness, porosities, and hydraulic conductivities of aquifer strata. Discuss significant uncertainties, anisotropies, and inhomogeneities. • Describe existing and known future offsite and onsite wells, including average flow rate, peak flow rate, water use, and completion depth. • Include maps of steady-state piezometric surfaces estimated with onsite and offsite wells at peak pumpage, average pumpage, and no pumpage. These maps should indicate the location of all wells and should annotate each offsite well with the drawdown of the piezometric surface attributable to both the onsite and offsite wells. Describe the methods of analysis, including assumptions used. • Describe existing and known future water rights (including Tribal water rights). • Describe any wetlands in the vicinity that might be impacted by a lowered water table. DG-4015, Page 29 • Evaluate the significance of present and future effects of onsite withdrawal on offsite wells. Additionally, describe any potential mitigation measures and state whether they will be implemented. Groundwater Quality Degradation (Plants with Cooling Ponds at Inland Sites) This section applies to plants at inland sites with cooling ponds. Table B-1 states the following: Sites with closed-cycle cooling ponds could degrade groundwater quality. For plants located inland, the quality of the groundwater in the vicinity of the ponds could be affected. The significance of the impact would depend on cooling pond water quality, site hydrogeologic conditions (including the interaction of surface water and groundwater), and the