Superfund Site: DIAMOND ALKALI CO.

Superfund Site Profile

To View the Administrative Order on Consent and list of Potentially Responsible Parties for the Lower 8.3 Miles of the Lower Passaic River - OU2 - Diamond Alkali Co site:  click here

The Record of Decision for the Lower 8.3 Miles of the Lower Passaic River can be found at:

2016 Lower 8.3-Mile ROD



The Diamond Alkali Superfund site includes the former manufacturing facility at 80-120 Lister Avenue in Newark, New Jersey, the Lower Passaic River Study Area (LPRSA), the Newark Bay Study Area and the areal extent of contamination. The LPRSA includes the 17-mile tidal stretch of the river from Dundee Dam to Newark Bay, and tributaries. The Newark Bay Study Area includes Newark Bay and portions of the Hackensack River, Arthur Kill and Kill van Kull. The area surrounding the site is densely populated and heavily industrialized.

Production of DDT and other chemical products began at 80 Lister Avenue in the 1940s. In the 1950s and 1960s, the Diamond Alkali Company owned and operated the facility, manufacturing agricultural chemicals, including the herbicides used in the defoliant known as “Agent Orange,” among other products. A by-product of these manufacturing processes was 2,3,7,8-TCDD (dioxin), an extremely toxic chemical. In 1971, Diamond Alkali sold 80 Lister Avenue.

In 1983, sampling by the state of New Jersey and the EPA at and near 80 Lister Avenue and in the river revealed high levels of dioxin. The site was listed on the Superfund National Priorities List (NPL) in 1984. Dioxin, pesticides and other hazardous substances were found in the soil and groundwater at 80-120 Lister Avenue; and dioxin, polychlorinated biphenyls (PCBs), metals, polycyclic aromatic hydrocarbons (PAHs) and pesticides were found in sediment in the Lower Passaic River.

New Jersey prohibits consumption of fish or shellfish from the Lower Passaic River and Newark Bay. Cleanup activities to date include immediate actions at 80-120 Lister Avenue and surrounding properties, removal actions in the Lower Passaic River, and the interim remedy for 80-120 Lister Avenue. In March 2016, EPA selected the remedy for the lower 8.3 miles of the Lower Passaic River. Additional investigations and planning for long-term cleanup are ongoing.