COKE AND GAS SITE UPLANDS REMOVAL ACTION
ENTACT performed a non-time-critical removal action of the 45-acre uplands area of a former coke and gas site in preparation for commercial redevelopment. The overall scope of work included demolition and removal of 38,000 cubic yards of surface and subsurface structures; resizing, crushing, and screening 53,000 cubic yards of stockpiled debris for reuse onsite, removal of 3,900 wooden pilings; excavating 30,000 cubic yards of non-affected overburden soil for onsite stockpiling and use; excavating and consolidating 50,000 cubic yards of source
FORMER MANUAFACTURED GAS PLANT (MGP) SITE REMEDIAL ACTION
ENTACT remediated an MGP site located in an urban area bordered by light industrial and commercial development, undeveloped land, and a shallow river. Historical releases of MGP residuals had impacted soil and groundwater, and contaminants migrating to the adjacent river’s bank affected an isolated sediment area. The overall scope included the development of a treatability study; demolition of concrete footings and slabs; excavation and off-site disposal of 10,500 tons of impacted soil; installation of 180 linear feet of 36-inch reinforced
FISHING CREEK SOUTH JETTY REHAB AND MAINTENANCE DREDGING
This project combines dredging and stone jetty improvements for the U.S. Army Corps of Engineers in Chesapeake Beach, MD. White Lake Dock & Dredge, Inc. (WLDD), a division of ENTACT, LLC, hydraulically dredged and conveyed more than 30,000 cubic yards of sediment from inner and outer harbors into a confined disposal facility (CDF). We also performed grading work and replaced the weir box outlet control structures inside the CDF. After the dredging, WLDD initiated jetty rock revetment work to repair
BAYFRONT REDEVELOPMENT
ENTACT completed the multi-phase remediation of a 100-acre industrial site near a river in preparation for mixed-use redevelopment. The initial phase covered 34 acres in the central portion of the site and lasted 3.5 years. We excavated approximately 932,000 cubic yards of chromium ore process residue (COPR) and chromium-impacted material and transported 53,000 truckloads for disposal off-site. To reduce water content in the waste materials, ENTACT designed, installed, and operated a groundwater extraction system. Finally, we imported, placed, and compacted
SANITARY LANDFILL NPL SITE
ENTACT was engaged to perform remediation services at a former sanitary landfill National Priorities List (NPL) site. The work area is approximately 2 acres in size and required the removal 23,800 cubic yards of impacted soil and more than 35,000 buried drums disposed of at the site in the early 1970s. Scope of work included the construction of a 200-foot-by-350-foot container management area pad; design and installation of a steel sheet pile wall to protect an existing soil-cement-bentonite slurry wall;
BROWNFIELD REDEVELOPMENT AREA REMEDIATION
ENTACT performed remediation activities at several blocks and lots at this site, representing a larger-area brownfield redevelopment project for future residences. Multiple industrial operations impacted the soil with the following contaminants of concern: polycyclic aromatic hydrocarbons (PAHs), volatile organic compounds (VOCs), polychlorinated biphenyls (PCBs), hexavalent chromium, chromium ore process residue (COPR), extractable petroleum hydrocarbon (EPH), pesticides, various metals and lead. Scope of work included design, procurement, and installation of a 1,600-linear-foot, 40-foot-deep permanent vertical hydraulic control system; dewatering, water treatment,
RARE EARTH PROCESSING FACILITY RADIOLOGICAL DECOMMISSIONING
ENTACT decommissioned, decontaminated, and demolished a former rare earth minerals processing plant in a larger chemical manufacturing complex. The site was approved for closure by the USEPA in 2015. Modeling was used to determine remediation goals for allowable soil concentrations to meet the regulatory requirement, which resulted in soil concentrations equal to 3 pCi/g of thorium-232 and 9 pCi/g uranium-238. Approximately 100,000 tons of radiologically impacted soil, sediment, construction debris, and 230,000 gallons of impacted water have been removed from
ACTIVE REFINERY TANK FOOTPRINT SUBSURFACE GROUND IMPROVEMENT
As part of a larger capital program, an active refinery sought to expand its footprint to accommodate 14 tanks and four pump pads. Before construction could start on the new structures, ENTACT performed subsurface soil treatment of soft saturated soils to minimize future tank foundations and pump pads settlement. The ground improvement treatment consisted of installing a series of 8-foot diameter soil-cement columns on an 11-foot by 11-foot grid underneath the planned footprint of each tank foundation. A series of
LOGISTICS PARK DEVELOPMENT
ENTACT completed soil and groundwater remediation activities on a former coal-fired power generating station impacted with polychlorinated biphenyls (PCBs), hexavalent chromium (Cr(VI)), chromium ore process residue (COPR) and extractable petroleum hydrocarbon (EPH) at concentrations that exceeded cleanup criteria for future site development. ENTACT performed the excavation, segregation, waste characterization, and off-site treatment/disposal of excavated Toxic Substances Control Act (TSCA) and Resource Conservation and Recovery Act (RCRA) hazardous and non-hazardous soil. After the removal of the impacted soil, we installed 7,500
FORMER SMELTER MIXED-USE REDEVELOPMENT
ENTACT completed remedial action activities that included managing and consolidating onsite debris and decontamination and demolishing remaining smelter buildings. We regraded over 1.3 million cubic yards of slag and soil – slag piles as large as 8.5 acres and up to 50 feet tall – representing five separate slag categories distinguished by color and gradation for utilization in distinct sections of the development; removed the impacted soil and sediment; and constructed a 185-acre soil cover system over the entire site.
CANAL SEGMENT CONTAMINATED SEDIMENT REMEDIATION
ENTACT performed remediation of mercury- and lead-contaminated sediments from an approximate 3,600-linear-foot segment of a closed canal. A temporary remediation support area was constructed with two dredge processing cells, a temporary water pretreatment system area, multiple staging areas along the canal, and a temporary water management system to complete the task. We performed the mechanical dredging of ~30,000 cubic yards of sediment from a floating barge assembly, dewatering and conditioning of sediments, and characterization, transportation, and off-site disposal. ENTACT finished
FORMER OILFIELD AND SERVICE FACILITY EXCAVATION AND BACKFILL SERVICES
ENTACT performed remediation of soils impacted by volatile organic compounds (VOC), nonaqueous phase liquids (NAPL), and benzene, toluene, ethylbenzene, and xylene (BTEX) at this former oilfield and service facility. The scope of work included shallow excavation of 3,268 cubic yards of impacted soils followed by a self-hardening cement-bentonite slurry-supported excavation of 13,000 cubic yards of impacted soils up to 52 feet deep; transportation and off-site disposal of ~25,500 tons of excavated material; backfilling of affected areas with over 6,500 cubic yards; and