Impoundments 1 & 2
The U.S. Environmental Protection Agency (USEPA) issued Record of Decision for Operable Unit 8 (OU8), commonly referred to as Impoundments 1 and 2, includes the following major remedy components:
- Excavation and dewatering of the impoundment material from Impoundments 1 and 2;
- Emission and odor control measures to protect workers and the surrounding community;
- Off-site shipment of the excavated material for treatment/destruction;
- Collection of the dewatered aqueous phase liquid for either on-site treatment and discharge or for offsite disposal;
- Treatment of any impacted soil and/or clay in the impoundments with concentrations above remediation goals via in-situ stabilization and solidification (ISS);
- Backfilling the excavated areas with existing berm materials from the impoundments not requiring treatment;
- Installing a protective cover over the entire OU8 footprint; and
- Implementing institutional controls, monitoring, and periodic reviews to ensure that the remedy remains protective of public health and the environment.
As part of the remedial design phase, remedy demonstration projects were performed in 2020, 2021, 2022, 2023, and early 2024. These demonstration projects provided important information to support the final design of the remedy, such as the rate of material removal and preferred containers for shipping of the dewatered material to off-site treatment facilities. During the demonstration trials a significant amount of material was safely removed from the impoundments, while meeting air quality criteria approved by both USEPA and NJDEP.
On September 24, 2024, USEPA approved the Remedial Design Report for the removal of acid tar materials from Impoundments 1 and 2 and on September 25, 2024, USEPA approved the Remedial Action Work Plan. These are two significant milestones allowing the project to officially transition from Remedial Design into Remedial Action. Material removal activities resumed in October 2024 and will continue seasonally (April-Dec) for several years.