Infrastructure

FORMER MGP SITE IN-SITU SOLIDIFICATION AND STABILIZATION

ENTACT completed site remedial work and in-situ solidification and stabilization (ISS) of impacted soils at an 8-acre former manufactured gas plant (MGP) site. The project was situated near industrial, commercial, and residential properties; community parking areas, a recreational park; and water district facilities, including water supply wells. Remediation included excavation, transportation, and disposal of 52,000 tons of MGP-impacted soils; in-situ solidification and stabilization of approximately 168,000 cubic yards of impacted material using cement-bentonite-slag grout; construction of a temporary containment structure

LNG EXPORT TERMINAL GROUND IMPROVEMENT

ENTACT performed soil improvement at this 1,000-acre site in preparation for the development of a Liquefied Natural Gas (LNG) export terminal. The project site is at an ideal location, situated on a ship channel that connects with the Gulf of Mexico. It features deep-water access, proximity to plentiful gas supplies, and ease of transport for buyers. The scope of work included soil improvement of 411,000 cubic yards of soft saturated clay to depths ranging from 4.0 to 8.5 feet, within

AGGREGATE MINER AND SUPPLIER SLURRY WALL PROGRAM

ENTACT originally served this major aggregate miner and supplier by replacing a cutoff wall over 9,000 feet high. This successful job and the relationship formed during the project established ENTACT as the Client’s dedicated slurry wall contractor. Following the successful completion of the first project, we constructed a 7,438-foot-long, 30-inch-wide soil-bentonite slurry wall to minimize dewatering efforts and facilitate dry mining operations. In addition to constructing a new slurry wall, our responsibilities included identifying and protecting many subsurface utility lines

TAR PONDS AND COKE OVENS SITE SOLIDIFICATION AND STABILIZATION

The tar ponds were filled with waste from a steel mill and coke oven, transforming the nearby tidal estuary with impacted sediments and sludge. The governments of Canada and Nova Scotia announced a plan to clean up the site and establish Open Hearth Park, a community gathering place. ENTACT developed solidification and stabilization mix designs in our treatability lab and confirmed the recommended formula through a successful field pilot program. We solidified and stabilized approximately 745,000 cubic yards of impacted

WET ASH IMPOUNDMENT CLOSURE

ENTACT completed the closure of a 140-acre wet fly ash impoundment containing approximately 13.4 million cubic yards of coal combustion residual (CCR). The project required draining the surface water via pumping and temporary drainage channels in the deposited ash and directing it to an area behind the main dam where a permitted outfall was located. The overall scope of work for the project involved lowering the main dam, removing the saddle dam, and constructing a new spillway for both dams;

INTEGRATED ENERGY COMPANY KEY SUPPLIER PROGRAM

ENTACT regularly performs remedial construction, geotechnical construction, and civil construction activities throughout the U.S. and select international locations for a major integrated energy company. Our 20+ year relationship demonstrates our commitment and partnership to our Client. We work with the Client’s team, assisting with preliminary design evaluations, site engineering, remedy selection, and cost budgeting in the planning phase of its many projects. We perform safe, effective, and cost-sensitive solutions at active and closed refineries, terminals, retail sites, oil field production

FORMER MGP SITE

ENTACT implemented in-situ solidification and stabilization at this former manufactured gas plant (MGP) to address the impacted materials. Through two phases of work, we successfully managed environmental conditions and prepared the site for redevelopment, while meeting our Client’s schedule and budget objectives. ENTACT performed various activities, including demolition and removal, off-site disposal and recycling of building slabs and subsurface structures. We performed collection, management, treatment and discharge of MGP contact water; removal, reinstallation or protection of utilities; plugging and grouting

FORMER FACTORY REMEDIATION AND REDEVELOPMENT

ENTACT remediated a former factory site – slated for residential and retail redevelopment – that was impacted by multiple contaminants, including arsenic and lead. The property is in a dense urban area, divided by a city street and bordered by city transit and right of ways (ROWs). The scope of work included onsite treatment and off-site disposal of 44,000 tons of non-hazardous material; onsite stabilization and off-site disposal of arsenic, volatile organic compound, and contaminant-impacted soils as much as 16 feet

INDUSTRIAL COMPLEX REMEDIATION AND REDEVELOPMENT

ENTACT performed remedial activities at this 2,200-acre industrial complex in preparation for mixed-use redevelopment. Using our internal technical and treatability skills, we developed a remedial solution to reduce the site’s high moisture levels to target objectives. This process included geotechnical evaluations, soil mixing, free draining, dewatering, and reagent evaluations of source materials. We performed critical items concurrently throughout our phased, multiyear site approach to maintain an efficient schedule. Major scope items included the removal of 3.9 million cubic yards of

FLY ASH IMPOUNDMENT CLOSURE AND DAM MODIFICATION

For this 300-acre wet fly ash impoundment closure, ENTACT conducted a multiyear phased approach for the project. Closure construction started with draining surface water via pumping or digging temporary drainage channels in the deposited ash to direct water to an area immediately behind the main dam. As we managed the surface water, we excavated the exposed fly ash and relocated and/or regraded the surface to meet subgrade elevations across the site. Work progressed from the highest to lowest elevations across

ACTIVE REFINERY PROCESS UNIT PROPOSED LOCATION

ENTACT performed soil remediation and ground improvement to address low-pH soils because of a sulfuric acid spill at the refinery. The ground needed to be stabilized to support the construction of a new process unit at the site. Subsurface soils consisted of saturated, soft, and sandy clay on top of very soft clay. ENTACT performed ISS on approximately 86,000 cubic yards from 22 to 24 feet below ground to strengthen this area. Using a combination of granulated ground blast furnace