Designed treatability study, fabricated site-specific treatment process equipment and implemented field pilot prior to full-scale
implementation
Excavation/on-site stabilization of 265,000 tons of lead impacted soils/sediments
Installation of sheet pile configurations to enable waste water management during remedial activities and to enable removal of 20,000 cy of
impacted sediments from lagoon
Construction of 6-acre monolith with treated materials, installation of clay cap
ENTACT performed remediation activities at this former battery breaking and secondary smelter site. ENTACT designed, obtained approval, and implemented an accelerated treatability study that significantly reduced the additive to material ratio while still achieving stringent performance criteria for compressive strength, groundwater standards, and permeability requirements. ENTACT then implemented the field activities that included excavation and on-site stabilization of 265,000 tons of lead impacted soils and sediments; installation of sheet pile and performing aggressive water management practices to enable removal of 20,000 cubic yards of impacted sediments from an on-site lagoon; construction of a 6-acre monolith with the treated materials, and installation of a clay cap cover system.
NPL Site
Excavation, T&D of radiological debris-contaminated soil
Ex-situ and in-situ stabilization and chemical reduction of 205,000 cy of chromium VI impacted soils
Removal/stabilization of 2,200 cy of surficial sediments within a tidal marsh
Installation of injection wells/monitoring wells for groundwater remediation
Installation of extensive stormwater collection and management system
100,000+ cy of site fill relocated, 46,000+ tons of crushed limestone placed, and 125,000+ cy of clean fill was imported, placed, and
compacted to achieve final site grades
Restoration using natural regeneration, seeding and plugs of the marsh grass, and spartina alterniflora
ENTACT completed large-scale remediation at this former ferrochromium alloy production plant. Site activities included excavation, management, and off-site disposal of (low level rad) radiological debris-contaminated soil; in-situ chemical reduction of chromium VI impacted groundwater; installation of approximately 207 temporary injection wells, and 20 temporary wells to monitor treatment success; removal of approximately 2,200 cubic yards of surficial sediments within a creek bed, followed by capping the affected excavation area with a geotextile and an 18-inch sand layer; chemical reduction, on-site placement, and capping of 205,000 cubic yards of chromium VI impacted soils (over 50-acres); construction of an extensive stormwater management system; and site restoration. ENTACT utilized amphibious low ground pressure (LGP) equipment in order to minimize impact to the surrounding tidal marsh during excavation and capping activities.
Redox (reduction/oxidation reaction) - Chemical, mechanical, and biochemical environmental remediation processes for rendering chlorinated hydrocarbons, pesticides, herbicides, explosives, energetics, and heavy metals chemically inert or neutral in their affect on the surrounding environment. Reduction refers to the gain of electrons by a molecule, atom, or ion. Oxidation refers to the loss of electrons by a molecule, atom, or ion. One or the other of these transformations might be used to change the chemical and/or physical attributes of soil contaminants so that they are environmentally acceptable and can remain in-situ and support beneficial use. Redox is initiated by the addition/injection of chemicals, reagents, microbes, enzymes, or bacteria designed to interact with and permanently change the targeted contaminant.
Bioremediation - Bioremediation is the use of biological mechanisms to destroy, transform, or immobilize environmental contaminants. Bioremediation of hydrocarbons can be accomplished by a variety of techniques. In all cases, breakdown of hydrocarbons is maximized by providing the best conditions for microbial activity, requiring a proper balance of moisture, nutrients, and soil oxygen.
