PCB-Contaminated Sediment Evaluation Results in Identification of Clear Solutions

Housatonic River, Pittsfield, Massachusetts

In June 1998, Weston Solutions, Inc. (WESTON^®) was contracted by the New England and Baltimore Districts of the U.S. Army Corps of Engineers (USACE) to provide technical support to U.S. Environmental Protection Agency (EPA) Region 1. WESTON was issued multiple task orders to manage highly visible assignments for data collection and risk evaluation, and to oversee approaches for remediating polychlorinated biphenyl (PCB) contaminated sites in multiple study areas and facilities of the Housatonic River in Pittsfield, Massachusetts.

WESTON quickly mobilized the resources needed to support this project, the largest sediment sampling program ever performed in the Northeast.  A local office and a local field laboratory were established to support surface water, sediment, soil, biota, and habitat sampling programs and hydrological studies. Technical resources to support a wide range of activities including geophysics, modeling, risk assessment, data management, and community relations were also provided.  As part of this project, WESTON created information management systems to store, integrate, evaluate, and present data findings, often using real-time data for analyzing and determining the direction of the study programs.  WESTON developed a Virtual Private Network (VPN), which gave authorized stakeholders access to project information (plans, reports, raw data, maps) on varying levels of authority.

An important aspect of this project required performing engineering evaluations and cost estimates for dredging a 1.5-mile reach of the river.  This included a detailed technical analysis of dredging approaches and river diversion options as well as a thorough review of the potential suitability of a wide range of PCB destruction, transformation, and isolation/separation technologies. Treatment options, such as thermal desorption, soil washing, and solvent extraction, were evaluated on a conceptual design level.

Because this project was at a sensitive public site involving a highly diverse group of stakeholders, including:  private industry; the general public; various levels of local, state, and federal government; conservation groups; Native American groups; consultants; and educators, WESTON established an Advocacy Group of national experts in the fields of ecology, toxicology, chemistry, and hydrogeology.

Advocacy Group experts independently assessed results and made recommendations for technical approaches, leading to the cooperative identification of permanent solutions for the PCB-contaminated sediments.