No-Impact Threshold Values for NRAP's Reduced Order Models

Last, George V.¹  Murray, Christopher J.¹  Brown, Christopher F.² 

[1] Pacific Northwest National Lab. (PNNL), Richland, WA (United States);Pacific Northwest National Lab. (PNNL), Richland,

关键词: Carbon Sequestration;    Threshold Values;    Reduced Order Models;    NRAP;   

DOI  :  10.2172/1158524
RP-ID  :  PNNL--22077
PID  :  OSTI ID: 1158524
Others  :  Other: AA9010200

美国|英语

来源: SciTech Connect

【 摘 要 】

The purpose of this study was to develop methodologies for establishing baseline datasets and statistical protocols for determining statistically significant changes between background concentrations and predicted concentrations that would be used to represent a contamination plume in the Gen II models being developed by NRAP???s Groundwater Protection team. The initial effort examined selected portions of two aquifer systems; the urban shallow-unconfined aquifer system of the Edwards-Trinity Aquifer System (being used to develop the ROM for carbon-rock aquifers, and the a portion of the High Plains Aquifer (an unconsolidated and semi-consolidated sand and gravel aquifer, being used to development the ROM for sandstone aquifers). Threshold values were determined for Cd, Pb, As, pH, and TDS that could be used to identify contamination due to predicted impacts from carbon sequestration storage reservoirs, based on recommendations found in the EPA???s ''Unified Guidance for Statistical Analysis of Groundwater Monitoring Data at RCRA Facilities'' (US Environmental Protection Agency 2009). Results from this effort can be used to inform a ''no change'' scenario with respect to groundwater impacts, rather than the use of an MCL that could be significantly higher than existing concentrations in the aquifer.