Nyanza Chemical Waste Dump
Case Study


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In early 2020, EnviEye detected higher than usual concentrations of toluene in the Nyanza Chemical Waste Dump area along Megunko Road in Operable Unit II. By identifying higher concentrations near "dense non-aqueous phase liquid" (DNAPL) sites, we were able to determine which groundwater sights required the most significant remediation. When DNAPL vaporizes, it produces high concentrations of harmful toluene. Toluene is known to damage the central nervous system, but the EPA has not found sufficient evidence of its carcinogenic effects. However, toluene is a precursor to benzene, another VOC with severe carcinogenic potential. In addition, it is known that primary solvents purchased in 1970 by Nyanza Inc. included nitrobenzene (30,250 lbs.), 2-nitrochlorobenzene (20,850 lbs.), 2-nitrotoluene (25,000 lbs.), and TCE (1,000 lbs.). Therefore, it is likely that the groundwater in toluene vaporization zones is also contaminated with benzene-containing DNAPL.


Following identification, we began working with the EPA to determine the optimal cleanup plan for neutralizing the toxic fume sources on Megunko Road. After months of attending community events and public forums, the community and EPA made a final decision on the remedy plan considering factors like cost, disruption, effectiveness, and time to execute.

The selected remedy is intended to reduce the concentration of contaminants in groundwater to levels that will be protective of human health for exposure to indoor air, such that the existing vapor mitigation systems are no longer needed, and to minimize the need for controls to protect residents. As of January 2020, the EPA has decided to launch a $20.5 million, 5 to 10 year initiative to drill into high DNAPL areas and excavate the contaminated groundwater.

For years, concerned Ashland residents have petitioned the EPA to take action against the cancer-causing vapors. Environa is a proud contributor to this environmental justice operation, and we hope to utilize our EnviEye Air Pollution Monitoring Network to raise awareness for similar injustices in the future. To review the final cleanup plan, click on the link below.