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Title: Baseline Risk Assessment Supporting Closure at Waste Management Area C at the Hanford Site Washington

The Office of River Protection under the U.S. Department of Energy is pursuing closure of the Single-Shell Tank (SST) Waste Management Area (WMA) C under the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO). A baseline risk assessment (BRA) of current conditions is based on available characterization data and information collected at WMA C. The baseline risk assessment is being developed as a part of a Resource Conservation and Recovery Act (RCRA) Facility Investigation (RFI)/Corrective Measures Study (CMS) at WMA C that is mandatory under Comprehensive Environmental Response, Compensation, and Liability Act and RCRA corrective action. The RFI/CMS is needed to identify and evaluate the hazardous chemical and radiological contamination in the vadose zone from past releases of waste from WMA C. WMA C will be under Federal ownership and control for the foreseeable future, and managed as an industrial area with restricted access and various institutional controls. The exposure scenarios evaluated under these conditions include Model Toxics Control Act (MTCA) Method C, industrial worker, maintenance and surveillance worker, construction worker, and trespasser scenarios. The BRA evaluates several unrestricted land use scenarios (residential all-pathway, MTCA Method B, and Tribal) to provide additional information for risk management. Analyticalmore » results from 13 shallow zone (0 to 15 ft. below ground surface) sampling locations were collected to evaluate human health impacts at WMA C. In addition, soil analytical data were screened against background concentrations and ecological soil screening levels to determine if soil concentrations have the potential to adversely affect ecological receptors. Analytical data from 12 groundwater monitoring wells were evaluated between 2004 and 2013. A screening of groundwater monitoring data against background concentrations and Federal maximum concentration levels was used to determine vadose zone contamination impacts on groundwater. Waste Management Area C is the first of the Hanford tank farms to begin the closure planning process. The current baseline risk assessment will provide valuable information for making corrective actions and closure decisions for WMA C, and will also support the planning for future tank farm soil investigation and baseline risk assessments.« less
Authors:
 [1]
  1. Washington River Protection Solutions LLC, Richland, WA (United States)
Publication Date:
OSTI Identifier:
1167089
Report Number(s):
TOC-WP--14-4991-FP.Rev.0
TRN: US1600034
DOE Contract Number:
DE-AC27-08RV14800
Resource Type:
Conference
Resource Relation:
Conference: WM2015 Waste Management Symposia, Phoenix, AZ (United States), 15-19 Mar 2015
Research Org:
Hanford Site (HNF), Richland, WA (United States); Washington River Protection Solutions LLC, Richland, WA (United States)
Sponsoring Org:
USDOE Office of Environmental Management (EM)
Country of Publication:
United States
Language:
English
Subject:
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES; 54 ENVIRONMENTAL SCIENCES; GROUND WATER; RISK ASSESSMENT; HANFORD RESERVATION; DECOMMISSIONING; SOILS; ORDERS; MONITORING; STORAGE FACILITIES; CONTAMINATION; PLANNING; TANKS; LAND USE; PUBLIC HEALTH; HAZARDOUS MATERIALS; SAMPLING; TOXIC MATERIALS; RADIOACTIVE WASTES; WELLS; REMEDIAL ACTION; RADIOACTIVE WASTE MANAGEMENT; RADIATION DOSES