EPA Superfund Site

DIAMOND ALKALI CO.

NJ | EPA ID NJD980528996

About this site’s exposure pathways: As of January 2025, the Diamond Alkali Superfund Site is considered Human Exposure Not Under Control because of ongoing ingestion of fish and shellfish caught from the lower Passaic River and Newark Bay complex. The Lower Passaic River and Newark Bay are under fish and shellfish consumption advisories, issued by New Jersey Department of Environmental Protection (NJDEP) based on polychlorinated biphenyl (PCB), dioxin, and/or mercury contamination. EPA has already initiated clean-up activities at the site. The planned activities to address this pathway include working with the state to ensure fish consumption advisory signs are posted, the ongoing remediation of contaminated material at the former Diamond Alkali facility which will prevent further migration of contamination to the Passaic River and Newark Bay, implementing the remedy for the lower 8.3 miles of the river, and designing the interim remedy for the upper 9 miles of the river.

EPA currently anticipates that human exposure will be under control by August 2057, when the Site is deleted from the National Priorities List (NPL).

EPA ensures community participation throughout the remedial process by meeting with residents and affected stakeholders, issuing public notices and updating fact sheets. A site profile has been established on the EPA website to keep the community informed of recent progress at the site. Additionally, an EPA Community Involvement Coordinator is assigned to the site and can address specific community concerns as they arise.