Former Market Street Gas Works

Containing harmful contaminants and adjacent to an urban area of Newark and the Passaic River, the site of a former manufactured coal gas plant was in need of remediation.

Over the years, the by-products of the coal gasification process (including coal and tar) had leached into the ground and contaminated both the water and soil. This concerned residents because the area was to be re-developed by the United States Army Corps of Engineers (USACE) as a public green-space for the city of Newark.

Conti was hired to restore the property and performed state of the art remediation techniques to remove Market Street’s contaminants. The team constructed three reinforced steel cofferdams at measurements of approximately 85 feet long, 365 feet long and 200 feet long. When combined with a dewatering system of shallow and more than 100-foot deep wells, piezometers and five tiers of internal bracing, the cofferdams allowed excavation to depths of 60 feet right next to the river. Conti also protected twin active gas mains with 30-inch diameters using 344 cubic yards of jet grout. Once excavated, Conti blended the contaminated soil with clean soil and cement kiln dust and transported it to thermal desorption facilities where it met strict acceptance criteria.

Conti performed 56,810 safe work hours with no lost time accidents and completed the project on schedule. The client re-developed this major riverfront site for the City of Newark and congratulated Conti for a job well done, expressing his satisfaction at having worked with such a professional team.

Water Supply & Discharge Systems

Natural gas combined-cycle energy plants often generate intense heat, especially when they power over 600,000 homes at once. This is why the new 738 megawatts West Deptford Power Plant would require the construction of a cooling system for LS Power.

The system includes pipe and pump structures designed to move water into the plant to cool the turbines. The pipes draw water from the local West Deptford greywater system to be pumped into the power plant.

Conti delivered this turnkey EPC contract to build the water supply and discharge systems that the power plant required. The team used two vertical turbine pumps with approximately 3,333 gallons per minute capacity to supply the power plant with cooling water. The pumps featured a Variable Frequency Drive System to control the volume of water to the power plant. Conti housed the pumps in a pre-engineered concrete underground pump station structure with a pre-engineered metal building that sits around an existing 72-inch corrugated metal pipe (CMP) water discharge line. To build the housing structure in the unstable soil, Conti drove 38 12-inch diameter concrete-filled pipe piles. The pipes traversed a wetland area that required drilling five feet under. Conti also provided a high-density polyethylene (HDPE) 24-inch pipeline to move the water to the power station, along with a 12-inch discharge pipe. The team installed an 8-inch electrical conduit to power the pump station and a 4-inch communication conduit for control from power plant to the pump station and vice versa.

Conti could not mobilize immediately pending the site permit, so took advantage of the down-time by scheduling material deliveries. Overall, the project was delivered on time, on schedule, and with zero safety incidents.

Conti traversed unstable soils and permitting delays to ramp up construction for the new power plant.

Fairless Power Plant

Producing enough power to supply nearly 300,000 homes.

The Fairless Power Plant is a crucial electricity provider in Fairless Hills, Pennsylvania. The plant became fully operational in 2004 and is owned by Dominion Energy (DE), who sells its output to the regional and national grid. This 1200 MW combined cycle station burns natural gas fuel using four GE Frame 7FA gas turbines, two GED D-11 steam turbines, and four duct-fired heat recovery steam generators (HRSGs) equipped with Selective Catalytic Reduction (SCR) for NOx reduction to single-digit levels.

Conti self-performed logistically challenging excavation and construction of the civil foundations for all buildings of this new power plant. The project involved extensive pile driving operations, for which Conti used state-of-the-art pile driving equipment and was able to self-perform all production work.

The project included installation of steel pipe piles. Prior to installation, the team poured structural pile concrete and installed reinforcing steel pipe cages to support the piles. Due to conflicts with underground utility locations, the team pre-augured piles and performed Pile Driver Analysis (PDA) tests, including compression and lateral load tests, to confirm that piles were driven properly for the structural stability of the building foundations. Drive-fit splices for the steel pipe piles where in excess of 88 feet.

Conti’s efforts and advanced project scheduling techniques enabled the team to complete the work to specifications in just nine months.

Conti used state-of-the-art pile driving equipment and self-performed all production work for this project.

Newark Airport Fuel Pipeline Modification

At one of the world’s largest and most heavily trafficked airports, Conti helps Newark Liberty maintain its aviation fueling system to industry and environmental standards.

Newark Liberty International Airport’s current fuel system was constructed in 1970 and needed repairs and upgrades to meet industry standards requiring centralized purchasing of Jet-A fuel for all users, which simplifies multi-pump fuel supply systems and piping networks. The Port Authority of New York and New Jersey called for upgrades to the current system, allowing it to function more efficiently.

Conti was responsible for Phase I of a three-phase multi-year fuel system modification program. We decommissioned the old single-wall welded steel pipe and installed approximately 29,000 linear feet of buried 22-inch double-wall steel pipe for the aviation fuel main line. The pipe included sensors for fuel leak detection and runs from the South Fuel Farm to the new Fuel Serving Area and reconnects to the Central Terminal Area. The pipeline routing will benefit a new Terminal A.

A two-position truck fill station loading rack was instructed airside next to the new Contact Water Treatment Facility (CWTF). This strategic location allows for faster fueling and results in less traffic. The new CWTF consists of three holding tanks, one reclaim tank and an oil water separator.

Modifications were also made to various components of the fueling system including valves, pumps and electrical controls. These changes will reduce both maintenance and electrical costs.

Transco Gas Compressor Station

Transporting natural gas around the country requires amazing efficiency. With thousands of miles of gas pipelines intricately networked underneath America’s soils, quality gas compressor stations, which pressurize natural gas so it is capable of moving through pipelines at high speeds, are essential to gas transportation. Transco sought to build such a station in the early 1990s, which would increase productivity at huge rates.

Conti worked on an aggressive, fast-track schedule to provide Transco with a state of the art, fully-operational gas compressor station. Conti’s workforces performed a minimum of ten hours a day, six days a week to complete construction on schedule.  

The team installed a 69,000 KV electrical substation generator, transformers, switchgear, grounding grids, and two 7,500 horsepower centrifugal compressor motors, in addition to the welding process and gas lines of many diameters and wall thickness. The work resulted in a capable compressor station constructed quickly and under budget. 

Conti was responsible for this turnkey project and performed construction activities, scheduling, health and safety, QA/QC documentation, facility testing, finish painting, cleaning, commissioning, and equipment and systems training. 

Conti broke ground and completed the project in record time thanks to strong coordination and scheduling.

Natural Gas Pipeline

UGI Utilities is one of the foremost providers of natural gas to communities in Pennsylvania and Maryland. Its 660,000 customers in 46 counties rely on the company’s continued service to power their homes daily.

In an effort to increase the service coverage of its natural gas pipeline distribution system in Pennsylvania, UGI contracted Conti to install new pipelines in Mechanicsburg.

Conti installed approximately 1,600 linear feet of 12-inch FBE coated 0.552-inch wall thick, high pressure steel natural gas pipe and directly buried it in a private right-of-way alongside a roadway. The team trenched the pipe across an active roadway in three locations. In all cases, the existing road pavement was saw cut and removed, and the trench was excavated for pipe installation. Once the pipe was installed, the road was backfilled and the asphalt pavement reinstalled. Conti also installed 1,174 linear feet of 12-inch Powercrete steel pipe via horizontal directional drill, 460 linear feet of which ran under wetlands, 714 of which ran under an intersection of Pennsylvania Department of Transportation state highway. Since work was performed along the side of the road, Conti implemented traffic control to ensure movement of traffic and safety for the traveling public. This included lane closures and lane shifts performed by trained traffic flagger personnel. 

Once the pipeline was complete and prior to tie-in, the pipeline was pressure tested with nitrogen, and a pig was run through the line for cleaning. The line was tied-in by UGI personnel to the existing high pressure line at two locations with a hot tap. 

After excavating and installing multiple pipes in residential areas and an active roadway, the project provides the Mechanicsburg community with updated gas service.

West Deptford Energy Station Black Start System

Named a Best Project of 2015 by Engineering News-Record, this new black start system provides immediate power regeneration in the event of an electricity outage emergency.

Touted as the cleanest fossil fuel plant in New Jersey, the West Deptford Energy Station’s black start system is LS Power’s long-anticipated upgrade to provide power to Gloucester County, New Jersey. At its construction completion in mid-2014, the plant was generating 738 megawatts of electricity, enough to power 700,000 homes.

Integrating the West Deptford Energy Station’s black start system into the existing system, the project team and the owner risked potential damage to the existing system or power outages to the entire grid. These risks are much greater than if the black start system had been built in conjunction with the energy station, which is why this project was practically unprecedented, making this a milestone project in the power world.

The team performed the design, engineering, procurement, construction, start-up, commissioning and testing of the integrated facility and system comprised of diesel-fueled internal combustion engines and installed and integrated these new systems into the gas-fired combined-cycle power generation facility. The work included installing three of the largest diesel engine driven generators Caterpillar makes in generator sound-reducing enclosures, constructing a diesel engine control system, modifying the existing facility control system and performing site improvements.

During a black start event, the power from the West Deptford Energy Station will enable other connected power plants to start.