PNNL

Abstract

During 2007 a Feasibility Study and Proposed Plan were completed that describe the selection of a combined groundwater pump-and-treat, monitored natural attenuation, and flow-path-control remedy for contaminants present in the Hanford 200-ZP-1 groundwater operable unit. In anticipation of the September 2008 signing of the final record of decision, work began on the development of a groundwater flow and contaminant transport model encompassing the 200-ZP-1 OU. The model was developed to support the preparation of the remedial design/remedial action work plan and subsequent design documents; to provide estimates of influent concentrations and mass removal rates for several contaminants of concern, including carbon tetrachloride, technetium-99, and hexavalent chromium; and to assist in the integration of remedial decision making across the Hanford Central Plateau. This paper describes the initial development and application of the flow and transport model, through Spring 2009.