Traitement des eaux usées
The Chemours Chambers Works industrial wastewater treatment plant (WWTP) is regulated and regularly inspected by the New Jersey Department of Environmental Protection (NJDEP). Specific requirements on how water will be treated, analyzed and discharged are stated in its permit and the plant is held accountable for operating within the permit parameters and reporting analytical results to the agency. Each day, the WWTP treats approximately 5 million gallons of industrial wastewater from the operations of the companies on the site. Additional sources of water treated at the WWTP include non-process cooling water, sanitary water from onsite restroom and shower facilities, landfill leachate, groundwater, and storm water. The WWTP consists of storage tanks, pretreatment and treatment systems.
Before its release through the site outfalls, water is treated and regularly sampled and analyzed to ensure it is within established permit limits. Analytical results are reported to NJDEP via the agency’s electronic Discharge Monitoring Report system. In addition, Chemours conducts weekly sampling and analysis for 18 PFAS compounds for monthly reporting to NJDEP and EPA monthly. A copy of the permit can be found here. NJ0005100 permit renewal application can be found here.
Site Investigation and Remedial Actions
The Chambers Works site has been in continuous operation for over 125 years producing a multitude of chemical products. Multiple phases of site investigation and remedial actions have been completed over the last 30 years as part of the Resource Conservation and Recovery Act (RCRA) corrective action program under the jurisdiction of the U.S. Environmental Protection Agency (EPA) through the Hazardous and Solid Waste Amendments of 1984 (HSWA) permit number NJD002385730 (effective on November 7, 1988).
In July 2017, a report was submitted to document environmental conditions at the site based on a comprehensive evaluation of the 125-year operational history and available environmental data. This report is titled Preliminary Assessment/Site Investigation (PA/SI) Report for the Chemours (formerly DuPont) Chambers Works Complex (the site) located in Deepwater, New Jersey. This PA/SI presents the 22 areas of concern (AOCs) identified at the site based on the potential for process-related constituents to have entered environmental media and references multiple phases of site investigation and remedial actions that have been previously completed. These investigations and remedial activities were conducted in multiple phases as part of the RCRA Corrective Action program as reported in the 2014 Comprehensive RCRA Facility Investigation (RFI) Report .
The RFI Report includes a robust conceptual site model (CSM) that integrates site-specific physical features, nature and extent of site- related constituents, potential migration pathways, and potential receptor information. The CSM documents the nature and extent of site- related constituents released from regulated units, solid waste management units (SWMUs) and areas of concern (AOCs). The RFI process at Chambers Works has been phased to evaluate and prioritize SWMUs within the site. The phased approach enabled three overlapping sets of objectives to be addressed:
- Achieve site stabilization
- Advance the site through the RCRA Corrective Action process
- Address high priority SWMUs on an accelerated schedule, outside of the phased RFI process.
As documented in the RFI, groundwater beneath the Chambers Works Complex is impacted due to historic releases from SWMUs and AOCs, with resultant multi-component dense non-aqueous phase liquid (DNAPL) source zones. Impacts to site-wide groundwater are addressed by a combination of engineering and institutional controls to prevent exposure. The site interceptor well system (IWS) is the primary means for site-wide groundwater control and has been in continuous operation since 1970. The IWS currently pumps a combined monthly average of at least one million gallons per day to create an inward hydraulic gradient to prevent off-site migration of groundwater. The IWS has been augmented by a sheet pile barrier along the Salem Canal and the Delaware River.
Groundwater monitoring is performed under several programs at the site to confirm the effectiveness of the hydraulic containment, monitor groundwater quality, and to meet RCRA post-closure requirements, as reported in semi-annual NJPDES-DGW reports.
Soil in the active manufacturing area is mostly covered with asphalt, concrete, or gravel preventing exposure to constituents in the subsoil. Direct contact with contaminants in the manufacturing area is limited based on these existing engineering controls and site wide institutional controls. Constituent concentrations in soil that may be impacting groundwater are addressed indirectly by the existing IWS and will be part of future remedial measures.
Ecological investigations have been conducted for the entire site. The former Carneys Point Works (the northern portion of the site) was addressed as a whole and no further action has been required. In addition, ecological investigations in the Salem Canal and the Delaware River are ongoing.
Groundwater at the site is part of the site-wide Classification Exception Area (CEA) and is not used for any purpose. The IWS will continue to operate, and groundwater will continue to be monitored per the site-wide monitoring programs that are in-place. The containment and monitoring programs will continue to be documented in the semi-annual NJPDES-DGW reports and submitted to the NJDEP and EPA. New technology will continue to be evaluated to meet site needs.
Chambers Works is subject to a variety of federal and state environmental regulations. A chronological list of major regulatory documents and permits related to operations and the corrective action program are noted below and are summarized in the 2006 Preliminary Assessment Report DuPont Chambers Works Complex, Deepwater, New Jersey.
- NJDEP Administrative Consent Order, NJDEP prepared, signed by DuPont in 1984, and signed by NJDEP in 1988. Modifications to include RFI AOCs were made to the permit in January 2015.
- Hazardous and Solid Waste Amendments Permit, 1988 (updated January 2015)
- Secure C Landfill Permits (Groundwater Protection Plan NJ0105872 dated November 5, 2014)
- NJPDES-DGW Permits (NJ0083429 Renewal October 30, 2014)
- NJPDES-Discharge to Surface Water Permits
- Water Allocation Permits (2122P Activity WAP150001, effective December 5, 2015)
- NJDEP Title V Operating Permit (BOP17003 – December 22, 2010 – December 21, 2020 with minor permit modifications)
- Classification Exception Area (CEA) Biennial Update 2016 – November 28, 2016 SRP PI 008221.