EPA Finalizes NJ Superfund Site Cleanup Plan
At the end of last month, the U.S. Environmental Protection Agency finalized an amendment to its original cleanup plan for the Cosden Chemical Coatings Corporation Superfund site in Beverly, New Jersey.
“EPA's test of the new method to treat this groundwater was a success, and now we can move forward in using it on a full scale,” said EPA Regional Administrator Lisa F. Garcia.
“We’ve already treated a tremendous volume of groundwater using the common method of pumping and treating, but this new technique will be a more efficient way to reduce the contamination.”
Cosden Superfund Site Background
The Cosden Chemical Coatings Corporation began operations in 1945, producing coatings for industrial applications. The formulation and manufacturing company recycled manufacturing solvents in tanks and drums onsite until 1974.
Following a grass fire at the facility in 1980, the New Jersey Department of Environmental Protection conducted an inspection and reportedly found spills, as well as several hundred unsecured drums.
After sampling the site in 1988, the EPA found the soil to be contaminated with heavy metals (lead and chromium) and polychlorinated biphenyls (PCBs). The groundwater had also been contaminated with volatile organic compounds (VOCs).
The 6.7-acre site was added to the Superfund National Priorities List in 1987, undertaking removal action to remove and dispose offsite 75 lab pack drums, 300 55-gallon drums, 2,000 gallons of bulk liquids and 350 empty containers ranging in size from five-gallon pails to 55-gallon drums. The company permanently closed in 1989.
In a 1992 Record of Decision, the EPA chose three solutions to deal with hazards that existed above-ground, in the soil and in the groundwater. The remedial action for above-ground structures was initiated in May 1995 and completed in spring 1996, including decontamination, demolition and disposal of all on-site structures, equipment and debris.
Afterwards, soil cleanup began in 1999 and was finished in March 2002, safely removing 10,711 tons of soil, 1,800 tons of debris and 3,000 gallons of liquid waste from the site. The area was then backfilled with clean fill, graded and revegetated.
In 2009, the EPA initiated the long-term treatment of the groundwater by building a groundwater extraction and treatment system (GETS). The GETS is estimated to have treated 282,311,828 gallons of water since its installation, removing approximately 13,000 pounds of total VOCs. The system is reportedly not operating due to the pilot study taking place at the property.
The EPA has completed immediate removal and remediation of above-ground structures and soil contamination and is currently working to remediate groundwater contamination. Three five-year reviews have been completed for the site, with the fourth five-year review expected to be issued in 2027.
Cleanup Proposal
At the end of August, the EPA proposed an update to its original cleanup plan that would reportedly supplement earlier groundwater treatment by injecting chemical oxidants directly into the aquifer to help break down hazardous contaminants into less toxic byproducts.
The agency reported that in-situ chemical oxidation uses various oxidizing chemicals to spur the reduction of harmful compounds, including VOCs, found in contaminated groundwater.
The U.S. Army Corps of Engineers and the EPA successfully demonstrated in-situ chemical oxidation using a network of 30 monitoring wells in 2021. The process could reportedly transform the remaining harmful contaminants at the Cosden site groundwater into less toxic byproducts.
According to the release, the method supplements the EPA’s earlier groundwater pumping and treatment work which has treated over 280 million gallons of water since 2009. Additionally, it offers long-term monitoring to ensure the cleanup is working as intended and other controls to prevent exposure to the hazards. The agency also plans to conduct additional sampling on and off the Cosden property for emerging contaminants, including per- and polyfluoroalkyl substances (PFAS).
The EPA reported that the NJDEP concurs with its preferred alternative as presented in the plan. The 30-day public comment period closed Aug. 29.
Proposal Approved
According to the Record of Decision Amendment, based on the detailed analysis of the remedial alternatives and public comments, the EPA has determined that in-situ treatment is the “appropriate remedy” to address the remaining groundwater source area contamination at the site.
The major components of the amendment include:
With these amendments, the EPA estimates that the source area Remedial Action Objectives will be achieved within five years, compared to the originally estimated 30 years from the previous cleanup plan. The objectives include preventing exposure to contaminant sources that present a significant human health risk and restore the contaminated groundwater to drinking water standards.
“Implementation of the selected remedy amendment will reduce the remaining groundwater source area contamination where concentrations are the highest and is expected to achieve the source area RAO established in this remedy amendment within five years after an estimated five rounds of in-situ treatment,” wrote the Agency.
Additionally, the EPA noted that comments were submitted during the public comment period, but no changes to the remedy amendment were warranted.
