DARAMEND® Reagent

In this presentation, environmental experts Dr. Alan Seech and Michael Mueller show how DARAMEND® Reagent can be used to treat soil contaminated with lindane and other chlorinated pesticides through a wide range of applications, both in situ and ex situ. This is the slide deck from the 14th International HCH Forum held in Zaragoza, Spain, in 2023 — one of Europe's most important conferences on the remediation of pesticides.

You can also watch Dr. Seech's presentation video on YouTube.

The case study showcases how DARAMEND® bioremediation successfully reduced extremely high PCE and TCE concentrations in soil—up to 3,800 mg/kg PCE and 220 mg/kg TCE—to below strict remedial standards in just three months. By applying sequential anaerobic–aerobic treatment cycles with a total amendment rate of 3%, the project achieved verified cleanup targets of 19 mg/kg for PCE and 1.2 mg/kg for TCE.

This cost‑effective approach delivered rapid, reliable remediation for chlorinated solvent–impacted soil. The results demonstrate a proven, sustainable solution for customers seeking efficient PCE and TCE soil remediation using DARAMEND® technology.

The project demonstrates how DARAMEND® bioremediation successfully treated 34 acres of soil contaminated with DDT, DDE, and Dieldrin, achieving 100% compliance with residential standards within four months. Average removal rates ranged from 38–68%, depending on whether one or two treatment cycles were applied. The performance‑based warranty ensured that the client only accepted results that met the agreed‑upon cleanup standards, significantly reducing project risk. This case highlights a proven, sustainable solution for organochlorine pesticide remediation, enabling large‑scale soil restoration directly on site while minimizing environmental impact.

At a confidential chemical facility in Ontario, California, DARAMEND® Reagent was applied to 350 tons of soil impacted by phenoxy‑acid herbicides and chlorinated pesticides, including 2,4‑D, 2,4,5‑T, DDT, DDD, and DDE. The treatment achieved exceptional reductions, with the concentrations of the target contaminants, 2,4‑D, 2,4,5‑T, and DDT, reduced by over 96%, 84%, and 91%, respectively. The enclosed treatment cell—with greenhouse covering, negative pressure, and carbon filtration—ensured safe handling of volatile compounds while enabling multiple treatment cycles. This project demonstrates a highly effective, on‑site remediation approach for herbicide‑ and pesticide‑impacted soil, delivering reliable contaminant destruction and strong environmental performance using DARAMEND® technology.

At a 90‑acre former oil‑field waste site in Oxnard, California, DARAMEND® Reagent was used to remediate soil and groundwater impacted by volatile organic compounds, including 1,2‑dichloroethane (1,2‑DCA), cis‑1,2‑dichloroethene, vinyl chloride, trichloroethene, and methylene chloride. The project combined excavation, ex situ soil vapor extraction, and placement of a DARAMEND®‑sand reactive blanket designed to degrade VOCs through in situ chemical reduction and long‑term dechlorination. Over nine years of monitoring, vinyl chloride declined from 25 ppb to below 0.5 ppb, and total chlorinated VOCs decreased from more than 77 ppb to less than 2 ppb. This integrated remediation strategy helped eliminate the need for vapor barriers on future residential buildings, offering a robust and sustainable solution for large‑scale redevelopment sites.

This case study demonstrates how even persistent organochlorine pesticides such as dieldrin can be treated safely, reliably, and cost‑effectively within just a few weeks. At a former agricultural site in Florida, DARAMEND® Reagent was applied in a 2,600‑ton in situ pilot project to rapidly reduce pesticide concentrations in soil to below the required remedial target. After only two treatment cycles, average dieldrin levels dropped by 67%, from 45.9 µg/kg to 15.1 µg/kg, meeting the site’s cleanup goal within 2–3 weeks at a total cost of approximately $12.50 per cubic yard.

This project was the second of three pilot projects under a research and development program designed to validate certain DARAMEND® Reagent applications for soils contaminated with chlorinated herbicides. After 10 months of treatment, the average metolachlor concentration in the main treatment cell had decreased to <1 mg/kg and in the heavily contaminated treatment cell to 11 mg/kg. In the control cell, the concentration remained unchanged.

DARAMEND® was applied at a pilot scale to approximately 100 tons of soil from the former Raritan Arsenal in Edison, New Jersey. Area 4 of the Raritan Arsenal was used as an explosives salvage and smelting area from World War I through the 1920s.

After 28 days of treatment, TNT concentrations had decreased to an average of 74 mg/kg and amino dinitrotoluene concentrations had been reduced to 25.9 mg/kg, which met the proposed cleanup goals for the site. Although 75 days had been scheduled for the remediation, the demonstration was terminated after only 56 days due to the rapid treatment rate.

This case study highlights how DARAMEND® bioremediation provides a proven, scalable, and cost‑effective solution for soils impacted by organic explosive compounds such as TNT, DNT, and tetryl. Across two pilot‑scale demonstrations and a full‑scale 3,000‑ton application at the Joliet Army Ammunition Plant (JAAP), DARAMEND® consistently achieved strong contaminant reductions and demonstrated reliable field performance on TNT‑impacted soil.
 

This case study demonstrates how DARAMEND® bioremediation delivers high‑performance treatment of extreme TNT and RDX contamination, even at concentrations rarely encountered in remediation projects. The Atlantic Division of the US Naval Facilities Engineering Command, together with the Yorktown Naval Weapons Station, initiated a multi‑batch, full‑scale program to treat soils impacted with organic explosive compounds, selecting DARAMEND® for its proven effectiveness and significant cost advantages. Across four ex situ batches of 1,200 yd³ each, soils with initial TNT concentrations averaging 10,000 mg/kg—and reaching 40,000 mg/kg—were consistently reduced to below the 15 mg/kg remedial goal, with RDX effectively treated in parallel.

This case study shows how DARAMEND® bioremediation provided a cost‑effective, reliable, and field‑proven alternative for treating TNT‑ and RDX‑impacted soils at the Tooele Army Depot (TEAD) in Utah. The US Army Corps of Engineers and MWH Constructors initiated corrective measures for approximately 10,000 cubic yards of contaminated soil, after conventional composting—originally considered the most economical option—became financially unfeasible due to rising fuel, transport, and material costs.

Pilot‑ and bench‑scale testing confirmed that DARAMEND® could consistently meet the site’s stringent remediation goals of 86 mg/kg TNT and 31 mg/kg RDX, leading to its selection for full‑scale implementation.