1. 4sq mi Carbon Tetrachloride (CCl4) Plume
2. Prepared Remedial Investigation (RI) report which narrowed the Contaminants of Concern (COC) to 7
3. Prepared Feasibility Study (FS) report that analyzed a variety of remedial alternatives
4. Integrated the FS with the Vadose Zone Source OU FS (PW-1/3/6)
5. Summarized the FS in the Proposed Plan (PP)
6. First Final Record of Decision (ROD) signed by EPA for Hanford Ground Water
7. Assisting with Remedial Design / Remedial Action (RD/RA) Work Plan

Detailed Project Description
Vista Engineering simultaneously executed the 200-ZP-1 (groundwater) and 200-PW-1/3/6 (vadose zone) Feasibility Studies (FS) encompassing the 200 West Area of the Hanford Site’s Central Plateau.  The objectives of this work were 1) formulation and analysis of vadose zone and groundwater remedial alternatives, and 2) recommendation of a preferred alternative presented to the public in a Proposal Plan.  Mr. Biebesheimer was the Project Manager for the 200-ZP-1 FS.  Vista Engineering published a FS report in July 2008.  This document includes discussions of project remedial action objective, alternatives for each of the representative sites, and a comparison of the effectiveness and reasonableness of each alternative and likely outcomes for each of the representative vadose zone waste sites as wells as the 200-ZP-1 operable unit which underlies more of these waste sites. 
Vista Engineering assembled a diverse team of technical experts including URS, Inc. (providing risk assessment services), EQM, Inc. (providing data validation and assessment services), S.S. Papadopulos and Associates, Inc. (providing groundwater modeling subject matter expertise) to prepare the 200-ZP-1 and 200-PW-1/3/6 Operable Unit Feasibility Studies.  Other major contributors included Fluor Hanford, Battelle PNNL, and the U.S. Department of Energy.  These large, highly-complex technical evaluations involved the analysis of hundreds of thousands of data points, contaminant and risk modeling, and assessment of various pre-conceptual treatment designs.  To manage configuration and control the integrity of project data, a Subversion source control platform was used to share various datasets over the internet.  This included sharing project reports, geospatial models and data, as well as serving analytical results.  As a result of the success of the process, Vista Engineering has been tasked by Fluor Hanford to assist them in developing a similar control mechanism for other Hanford RI/FS projects.

Detailed Project Description

Vista Engineering executed the 200-PW-1/3/6 (vadose zone) Feasibility Study (FS) in conjunction with the 200-ZP-1 (ground water) FS in the 200 West Area of the Hanford Site’s Central Plateau.  Mr. Moser was the project manager.  The objective of the 200-PW-1/3/6 FS was to develop and evaluate alternatives for remediation of the waste sites in the Plutonium/Organic-Rich Operable Unit (OU) Group and for the CCl4 that had migrated beyond the boundaries of the known CCl4 disposal sites in the 200-PW-1 OU.  Additionally, the FS refined requirements, objectives, and general response actions.  Alternative actions were considered to provide a range of potential responses to address site-specific conditions.  The alternatives were evaluated against two threshold and five balancing CERCLA criteria.  A preferred alternative was presented to the public for review and comment in a Proposed Plan (PP).  The EPA then prepared a CERCLA Record of Decision (ROD) that identified the remedial alternative(s) used for the Plutonium/Organic-Rich OU Group waste sites and for the CCl4 that had migrated beyond the boundaries of the known CCl4 disposal sites in the 200-PW-1 OU.