 | Vol. 7 No. 2 Fall 1999 |
| A Newsletter About New Jersey's Water Quality Programs |
DRBC Proposes Wasteload Allocations for the Delaware Estuary
by Debra Hammond, Chief, Bureau of Point Source Permitting - Region 2
In 1996, the Delaware River Basin Commission (DRBC) adopted amendments to its regulations regarding the control of toxic pollutants from point source discharges to the tidal portion of the Delaware River and its tributaries. These rules established the stream quality objectives and the regulatory framework for instituting Wasteload Allocations(WLAs), where necessary, to meet stream quality objectives for toxic pollutants. WLAs, which are prescribed to maintain water quality standards, are an assignment of pollutant loadings to point source dischargers. Based upon the rule amendments, the DRBC published a report, in December 1998, entitled "Wasteload Allocations for Volatile Organics and Toxicity: Phase 1 TMDLs for Toxic Pollutants in the Delaware River Estuary." The report includes an evaluation of 76 discharges to the Delaware River Estuary located in New Jersey, Pennsylvania, and Delaware. (A total of 39 New Jersey facilities were evaluated in the report.) These discharges are subject to proposed WLAs for 1,2-Dichloroethane, Tetrachloroethene, and Whole Effluent Toxicity.
In developing the WLAs for volatile organics and toxicity, the DRBC first conducted an independent evaluation of each discharger's impact to the Delaware River Estuary using a baseline analysis. The facility's pollutant loading was reduced, if necessary, to meet stream quality objectives. For this evaluation, an effluent was assumed to discharge at a concentration allowed in the DRBC's Effluent Limitation Guideline (ELG) or at a concentration based on actual data, if data was available and the facility was not covered by an ELG. After assessing each facility's impact, a multiple discharge analysis was done to determine whether the Delaware River Estuary would meet stream quality objectives when all dischargers were collectively considered. If the stream quality objectives were not met, the largest contributors were further reduced. A summary of the findings for New Jersey discharges are listed below:
1,2-Dichloroethane
Baseline reductions were required for 1,2-Dichloroethane at the Camden County MUA. Since stream quality objectives were not met in the multiple discharge analysis, equal marginal percent reductions were required at the Gloucester County MUA, Camden County MUA, and Mount Holly Sewage Authority.
Tetrachloroethene
Baseline reductions were required for Tetrachloroethene at Hamilton Township (Mercer County). Since stream quality objectives were not met in the multiple discharge analysis, equal marginal percent reductions were required for the Camden County MUA and Hamilton Township discharges.
Whole Effluent Toxicity
Acute and chronic endpoints (in toxic units) were evaluated for Whole Effluent Toxicity (WET). The DRBC performed only a baseline analysis in Phase 1. A multiple discharge analysis will be included in Phase 2, which is scheduled to be completed in 2002. Reductions, through acute and chronic WET wasteload allocations, are required at the following facilities: the DuPont Chambers Works, the Camden County MUA, Hamilton Township, and the City of Trenton.
Public hearings on the proposed Total Maximum Daily Loads (TMDLs) were held by the DRBC on May 3 in Wilmington, Delaware, on May 5 in West Trenton, New Jersey, and on May 11 in Philadelphia, Pennsylvania. The DRBC is currently evaluating the comments received on the proposal and is expected to issue a response document by September, 1999.
While the Phase 1 report includes WLAs for all facilities evaluated, the DEP must still decide whether an actual effluent limitation will be required at the Gloucester County MUA, the Camden County MUA, Hamilton Township, the City of Trenton and the DuPont Chambers Works. If necessary, the DEP will reopen NJPDES permits to incorporate new or more stringent effluent limitations within six months of the adoption of the WLAs. A copy of the DRBC report can be obtained from the DRBC website at www.state.nj.us/drbc/public.htm.
Next Step - PCBs
In June 1998, the DRBC released a report documenting current and historic sources of polychlorinated biphenyls (PCBs). PCBs contribute to the toxic contamination of fish, which has lead to the issuance of fish consumption advisories for striped bass, white perch and catfish. In its report, the DRBC indicates that the current problem cannot be attributed solely or predominantly to historic sediment contamination, as many scientists previously believed. Ongoing discharges entering the estuary from sewage treatment plants, combined sewer overflows (CSOs), and tributary streams are sufficient to cause water quality problems. Other studies conducted by the DRBC, Delaware Estuary Program, and the U.S. Army Corps of Engineers documented that in addition to PCBs, there are other elevated levels of toxics in the river. These include polynuclear aromatic hydrocarbons (PAHs), DDT-related pesticides, and heavy metals such as chromium, copper, lead, mercury and zinc.
The DRBC plans on proposing draft TMDLs for PCBs, chlorinated pesticides and selected metals in the Delaware Estuary in 2002. The first step in this process will include point source monitoring for PCBs using analytical methods with a very low detection level. Dischargers will receive a formal request from the DRBC for this monitoring in the fall of 1999. The proposed effluent sampling plan is designed so that all monitoring and analysis will be completed by December 2000.
A meeting to discuss the PCB strategy and the monitoring request is being scheduled for October 1999. An announcement regarding the time and place of the meeting will be forthcoming.
A copy of the PCB report can be obtained from the DRBC website at www.state.nj.us/drbc/public.htm
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Last revision Monday, August 30, 1999