East Orange Former Manufacturing Facility

Soil and groundwater at a former manufacturing facility in East Orange, NJ were impacted by trichloroethylene (TCE), cis-1,2-dichloroethene (cis-1,2-DCE) and vinyl chloride (VC) due to historical releases. The geology of the impacted matrix was primarily red-brown clayey silts with some occasional layers of fine sands.

TCE concentrations in groundwater were as high as 99.1 mg/L. In November 2015, IET implemented an in situ chemical reduction (ISCR) remediation program to enhance both abiotic and biological reductive processes (U.S. Patent #7,531,709).

The primary goal of the remediation program was to limit plume migration to downgradient areas.

The injection program included the application of emulsified zero valent iron (EZVI) to destroy source mass and minimize contaminant flux, ZVI, Provect-IR, and additional site-specific reagents including kelp and Vitamin B12, to enhance abiotic and biotic reductive dechlorination processes.

During November 2015, a total of 43 direct push injection points were utilized to distribute approximately 6,435 gallons of remedial solutions within the targeted treatment areas.

Overall, all monitoring wells recorded considerable decreases in TCE concentrations. Several post-treatment samples were collected and analyzed over approximately 20 months to evaluate treatment program progress.

Post-treatment groundwater pH remained near neutral (6.3-6.5 pH units), ideal for dehalogenic bacteria. Strong reducing conditions were maintained (ORP: -78 to -106 mV). Elevated concentrations of dissolved gases (methane, ethane, ethene) confirmed ongoing fermentation and controlled methanogenesis.

This project demonstrates IET's synergistic combined-remedy approach — integrating abiotic zero-valent iron (ZVI) treatment with biotic enhanced reductive dechlorination (ERD) in a single injection event. EZVI (Emulsified Zero-Valent Iron) provides the abiotic component: nanoscale ZVI particles within a biodegradable emulsion directly contact and dechlorinate DNAPL chlorinated solvents in the source zone. Provect-IR provides the biotic component: a controlled-release organic substrate containing ZVI that slowly ferments over 3–5 years, releasing hydrogen donors that sustain dechlorinating microbial communities.

The supplemental kelp and Vitamin B12 additions further enhance the biological treatment pathway. Kelp (seaweed extract) serves as a complex organic electron donor with a staggered fermentation profile — providing both rapid and slow-release hydrogen. Vitamin B12 (cobalamin) is a cobalt-containing coenzyme that directly catalyzes the reductive dechlorination of PCE and TCE, and is particularly effective at accelerating the rate-limiting vinyl chloride → ethylene conversion step that often stalls at chlorinated solvent sites.

The 43 direct push injection points distributed approximately 6,435 gallons of remedial solutions across the targeted treatment areas during the November 2015 field program. Direct push delivery is ideal for this combined-remedy approach because it enables precise placement of the reagent cocktail at the target depth intervals where DNAPL mass and dissolved-phase contamination are concentrated. The multi-amendment formulation in a single injection event creates both immediate abiotic treatment (EZVI) and sustained biological treatment (Provect-IR + kelp + B12) from a single mobilization.

East Orange, New Jersey is located in Essex County within the Newark Basin physiographic province. The shallow geology consists of Quaternary-age alluvial deposits overlying the Triassic-Jurassic age Passaic Formation (red beds) — predominantly red shale, siltstone, and sandstone. The site's clayey silt geology (noted in the Key Success Factors) is characteristic of the weathered residual soil over these red bed formations, which creates low-permeability conditions that challenge conventional remediation approaches.

Clayey silt geology is particularly difficult for in-situ remediation because the low permeability limits reagent distribution through conventional gravity-fed injection. IET's direct push injection system overcomes this by delivering reagents under pressure, creating hydraulic fractures and preferential pathways that distribute the amendment cocktail beyond the immediate injection point. The 20-month post-treatment monitoring period documented in the results section demonstrates the sustained effectiveness of the combined-remedy approach in these challenging low-permeability soils, with 6 wells achieving 100% TCE reduction and strong reducing conditions (ORP: -78 to -106 mV) maintained throughout the treatment zone.