- Odor Control and Vapor Management Systems
- Temporary Structures and Enclosures
- Subsurface Structure Demolition
- Free Product Recovery
- Removal of Coal Tar Waste, Debris and Residual Materials
- Soil Solidification and Stabilization

ENTACT implemented remedial action to address a coal tar impacted ravine abutting a river in preparation for residential redevelopment. Scope of work included excavation and stockpiling of clean overburden soils to allow installation of a sheeting wall; installation of a dewatering and treatment system installed in combination with the sheet pile wall; treatment and discharge of collected groundwater; excavation, solidification, and off-site disposal/thermal processing of 10,000 tons of coal tar residuals and contaminated soil; and site backfill, grading, and restoration.
ENTACT re-designed the steel sheet pile wall, which was a critical element of the project approach, to key into bedrock as well as hard-pan glacial till (with Toe Pins) without internal rakers allowing for greater flexibility within the ravine. A portion of the wall was designed to be left in place as a cut off wall for inaccessible waste materials. Specialized steel sheets were pre-injected with a hydrophilic (VOC resistant) expanding polymer to ensure a water-tight seal. The ravine required a 24-hour dewatering effort with all surface and groundwater running through a treatment system designed to remove particulate and organics. In excess of 670,000 gallons of water was treated and discharged. All work was performed during real time air monitoring activities. ENTACT utilized foam odor suppressants, good work practices, and daily soil cover to control odors.
ENTACT remediated this former MGP site located along a navigable waterway and adjacent to a residential neighborhood. Scope of work included decontamination and demolition of various above-ground structures, subsurface tar wells, gas holders, and pier; installation of sheet pile and cofferdam system to prevent failure of riverbank and ensure structural integrity of an on-site building during excavation activities at depths up to 26 feet below the river level; dewatering of excavation areas, containment, and transport to an on-site water treatment system; excavation, on-site solidification, and off-site disposal of over 80,000 tons of coal tar impacted materials and MGP wastes; and site backfilling and restoration. Additional activities included removal of a gas holder, soils and sludges from inside a warehouse that required level B PPE.
