Document: NRC Regulatory Guide
Document ID: e5306f4f-dc8c-4f60-a71c-af7ad4080384
Document Type: regulatory_guide
Title: Aquatic Environmental Studies for Nuclear Power Stations + HISTORY - HISTORY 12/2014 – DG-4023 -Proposed New Guide
Source: NRC Regulatory Guide Division 4
Source URL: https://www.nrc.gov/docs/ML1318/ML13186A085.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-4.24
CFR Part: 
CFR Title: 

Content:
sult from discontinued thermal discharge or alteration of shoreline or in-water structures during decommissioning. Other activities that could affect aquatic resources include, but are not limited to, storm-water runoff during removal of contaminated soil, dredging of contaminated or uncontaminated sediment, and modification of barge docks or other support facilities. Decommissioning is generally not expected to result in significant adverse ecological effects when ground or in-water disturbance is limited to the former operational area, but reworking the ground surface could have adverse impacts because of changed surface drainage patterns that may affect aquatic communities. Characterization of ecological conditions before site DG-4023, Page 24 redevelopment would be helpful when determining how to manage and evaluate ecological resources on decommissioned sites. Many of the same aquatic environmental baseline and impact analyses described above could help support the review of decommissioning impacts affecting aquatic biota and habitat. Analysts should quantify habitat modifications and losses and analyze impacts to important species and assemblages in the vicinity of the site. C. STAFF REGULATORY GUIDANCE 1. Because precise predictions and assessments of impacts on aquatic ecological systems are not always possible, the NRC recommends reasonable professional interpretations when quantitative prediction is not practicable. 2. Analysts should exercise professional judgment to identify appropriate analytical methods to support NRC licensing actions. Analysts should contact federal, state, and local regulatory agencies and search recent scientific literature for specific analytical protocols. 3. Baseline investigations should be broad enough, long enough, and completed early enough to support anticipated impact analyses and monitoring that federal and state agencies might require. These investigations may be prepared as separate reports or presented as part of