KEMRON/Arrowhead Joint Venture, LLC is performing a $34.6 million remedial action at the Velsicol Chemical Corporation/Hardeman County Landfill Site North Disposal Area in Tennessee. The approximately 20-acre disposal area contains nearly three linear miles of former waste trenches where an estimated 200,000 drums of pesticide-manufacturing waste were disposed between 1964 and 1973.

Historic disposal activities resulted in contamination of landfill waste, subsurface soil, groundwater, surface water, soil vapor, and air. Constituents of concern include heptachlor, dieldrin, endrin, hexachlorocyclopentadiene, carbon tetrachloride, and chloroform, with carbon tetrachloride and chloroform identified as the predominant volatile organic compounds released from the disposal areas.

Soil Vapor Extraction System Construction: A primary component of KAJV’s work is construction of a large-scale soil vapor extraction (SVE) system designed to remove contaminant vapors from the subsurface. The project includes installation of approximately 180 SVE wells and vapor monitoring points in three phases, along with the civil, mechanical, and electrical infrastructure required to collect and treat extracted vapors.

Wellfield construction includes sonic drilling and installation of the SVE extraction and monitoring network. The treatment system is being constructed with the objective of removing 90 percent of harmful subsurface vapors from the North Disposal Area.

System Commissioning and Long-Term Operations: In addition to wellfield and treatment-system construction, KAJV’s scope includes updating the conceptual site model, system shakedown and commissioning, performance monitoring, and eventual system shutdown. Following construction and startup, the joint venture is scheduled to provide approximately 10 years of operations and maintenance for the SVE system.

The project integrates remedial construction with long-term treatment and monitoring to reduce the mass and migration of volatile contaminants remaining beneath the disposal area and support the site’s long-term CERCLA remedy.

Project Highlights

• $34.6M initial contract value
• 20-acre North Disposal Area
• Approximately 200,000 drums historically disposed
• Nearly 3 miles of disposal trenches
• Approximately 180 SVE wells and monitoring points
• 90% vapor-removal objective
• Approximately 10 years of O&M following system construction