ESI won a performance-based contract to bring chlorinated solvent contaminated soil and groundwater at an active dry cleaner site to specified cleanup levels within one year of system operation. If EPA specified cleanup levels are not met then ESI will be subject to forfeiting a performance bond of over $300,000.

The EPA suspects this site, along with several others, is contaminating the municipal drinking water supply of Columbus, NE.

This project was conducted as a subcontractor to IT Corporation under the EPA Region 7’s Rapid Response Services (ERRS) Contract. Under this fast track project, ESI constructed a partial system that included a block treatment building and an assortment of horizontal and vertical SVE wells and shallow and deep AS wells, conducted a pilot test, and completed final remediation system design within four months. The system was deployed shortly after that.

The remediation system consisted of two 75 hp high vacuum blowers (1,700 and 1,000 cfm) for 45 shallow SVE wells and three 50 ft horizontal SVE wells, two 10 hp (500 cfm) regenerative low vacuum blowers for 11 deep SVE wells, and two 50 hp rotary screw compressors (125 and 230 cfm) for 28 AS wells. Additionally, we installed three 5,000 lb. vapor phase carbon vessels with a heat exchanger unit to increase adsorption capacity provide off-gas treatment.

A programmable logic control (PLC) system was engineered to improve system reliability and operational effectiveness. The system’s flexible operational design considered diverse soil conditions including shallow dense clays underlain by fine sands and coarse gravels. Air and vacuum flow could be independently adjusted at every well and to entire sections of the treatment area.

Site work was conducted without any accidents and with minimal disruption to dry cleaner operations. Closure criteria were achieved in all soil & groundwater compliance locations well before the bond forfeiture deadline.