Evaluation of Groundwater Impacts to Support the National Environmental Policy Act Environmental Assessment for the INL Remote-Handled Low-Level Waste Disposal Project

Schafer, Annette ; Rood, Arthur S. ; Sondrup, A. Jeffrey

Idaho National Laboratory

关键词: Us Superfund;    Sediments;    Sorption;    Thickness;    Us National Environmental Policy Act;   

DOI  :  10.2172/993153
RP-ID  :  INL/EXT-10-19168
RP-ID  :  DE-AC07-05ID14517
RP-ID  :  993153

美国|英语

来源: UNT Digital Library

【 摘 要 】

The groundwater impacts have been analyzed for the proposed RH-LLW disposal facility. A four-step analysis approach was documented and applied. This assessment compared the predicted groundwater ingestion dose to the more restrictive of either the 25 mrem/yr all pathway dose performance objective, or the maximum contaminant limit performance objective. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives. The analysis was prepared to support the NEPA-EA for the top two ranking of the proposed RH-LLW sites. As such, site-specific conditions were incorporated for each set of results generated. These site-specific conditions were included to account for the transport of radionuclides through the vadose zone and through the aquifer at each site. Site-specific parameters included the thickness of vadose zone sediments and basalts, moisture characteristics of the sediments, and aquifer velocity. Sorption parameters (Kd) were assumed to be very conservative values used in Track II analysis of CERCLA sites at INL. Infiltration was also conservatively assumed to represent higher rates corresponding to disturbed soil conditions. The results of this analysis indicate that the groundwater impacts for either proposed facility location are expected to be less than the performance objectives.