Alterra Industrial Outdoor Storage (Alterra IOS) and Eco Materials LLC have opened a $40-million soil-wash facility in South Philadelphia that converts contaminated soils into clean aggregates for reuse in construction.
The partners say the project marks a first-of-its-kind urban model for turning waste into market-ready material. “We’re transforming dirty soil into clean, reusable material on site,” Alterra IOS co-founder and managing partner Leo Addimando said. “And we’re doing it by cutting costs, reducing emissions and keeping the entire process local.”
The facility, situated on a five-acre parcel acquired for $5.75 million in June 2024, is designed to process up to 250 tons of material per hour, reclaiming as much as 85% of incoming soils as washed stone, masonry sand, and other aggregates that meet C-33 specifications.
A closed-loop system reuses up to 95% of wash water, aided by onsite stormwater capture; Eco Materials projects the operation will divert about 700,000 tons of soil per year from landfills. Many urban sites require remediation, and the facility gives contractors a place to take damaged soil to be remediated and reused if a project demands all new soil or remediation methods that can’t save the existing soil.
CDE Group, a global supplier of wet processing systems, designed the soil-wash process. Incoming loads are first scalped and screened to remove oversize debris. The remaining soils are washed and separated by particle size, with log-washers scrubbing fines from the stone.
Hydrocyclones and dewatering screens then recover sand fractions. Clarifiers and filter presses treat the slurry water mixture, allowing most of it to be cycled back into the system. According to Eco Materials and CDE Group’s technical documents, reviewed by ENR, this staged approach yields a range of products—from contractor-grade stone to C-33 concrete sand—produced entirely from soils that would otherwise have been landfilled.
Schematic overview of the soil-washing process from a U.S. EPA remediation technology bulletin, showing initial screening, separation of coarse and fine fractions, water treatment, and recycled water loops. Image: U.S. EPA.
Andrew Paluszkiewicz, managing partner and director of operations at Eco Materials, said the plant demonstrates that circular practices can scale in mainstream, urban construction.
“We believe construction and environmental responsibility can, and should, go hand in hand,” he said. “Our facility proves that sustainable resources can be reused time and again, dramatically reducing landfill waste and helping to conserve our planet’s limited natural resources.”
Eco Materials also points to longer-term potential in concrete applications. Paluszkiewicz said substituting recycled sand for a portion of virgin fine aggregate could reduce embodied carbon. “The focus on carbon content of concrete has been on cement,” he said, “but we see the potential to address that factor in aggregates as well.”
The site’s location near the interchange of Interstate 76 and Interstate 95—and the redeveloping Bellwether District—was chosen for access and efficiency, the partners explained. Alterra and Eco Materials say the looped traffic pattern allows more than 100 trucks per day to enter and exit without bottlenecks. Being near two major highways makes the Philadelphia plant a three-hour drive or less for contractors with projects in New York City, Washington D.C,, Baltimore, Atlantic City and Trenton.
The partners expect recovered aggregates to find steady demand in roadbuilding, slab-on-grade work, drainage, and environmental infrastructure.
Eco Materials co-founder Ken Griffin, a veteran of large-scale excavation projects, said he helped design the business model to address long-standing regional gaps in both contaminated soil disposal and aggregate supply.
By placing remediation and materials production at the same location, he added, the plant reduces hauling distances, lowers disposal costs, and makes recycled products more cost-competitive with virgin stone and sand.
Addimando described the Passyunk plant as a replicable model for other metropolitan areas facing similar challenges. “This facility represents the future of construction, where sustainability and profitability go hand in hand,” he said.
Paluszkiewicz added that the visibility of the operation was intentional, with landscaped entry points and transparent processing lines. “We want contractors, regulators and the public to see what responsible materials management looks like,” he said.
By reducing both waste disposal and aggregate sourcing miles, they assert the South Philadelphia facility sets a precedent for cost savings and carbon reduction in regional construction.
