Document: NRC Regulatory Guide
Document ID: f0baf50b-5bb7-4783-b2f9-9586e09c97e1
Document Type: regulatory_guide
Title: Preparation of Environmental Reports for Nuclear Power Stations + HISTORY - HISTORY 02/2017 – DG-4026 , Proposed Revision 3 09/2014 – Periodic Review of Revision 2 – Revise (Rev. 3)
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML1611/ML16116A068.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.2
CFR Part: 
CFR Title: 

Content:
c environment (e.g., climate and land use). When a mathematical model is used to support the evaluation of hydrologic characteristics, the applicant should describe the conceptual basis for the model, including the rationale for eliminating plausible alternative conceptualizations, the assumptions used in developing the model, the range of applicability of the model, input data used, the basis for boundary conditions, parameter estimation and calibration procedures followed, and estimates of uncertainty in model forecasts. The applicant should provide sufficient data to permit staff evaluation of modeling results, including input files used to obtain the model results and a description of any post-modeling analyses used by the applicant. 2.2.1 Hydrology The applicant should describe the hydrologic characteristics of surface waterbodies and groundwater aquifers that could be affected by station water use or be affected by building or operating the station. These characteristics collectively define the supply of water within the ROI, including the location, quantity, and temporal variability of that supply. The applicant should include the following information in the ER: • Discussion of rivers and streams including, but not limited to, drainage areas and gradients, discharge, bathymetry, wetlands and floodplain descriptions, flood and drought characteristics, flood control measures, and other hydrographic modifications. • Discussion of lakes and impoundments including, but not limited to, bathymetry, temperature, currents, inflows and outflows, evaporation, seepage, and a description of reservoir characteristics (e.g., elevation-area-capacity curves) and operations. • Discussion of estuaries and oceans including, but not limited to, bathymetry, tidal and nontidal currents, temperature, salinity, sedimentation rates, and sediment gradation and sorption characteristics. • Discussion of groundwater including, but not limited to, descriptions of aquifers and