[Federal Register Volume 64, Number 33 (Friday, February 19, 1999)]
[Notices]
[Pages 8335-8336]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 99-4150]


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DELAWARE RIVER BASIN COMMISSION


Notice of Determination Regarding the Assimilative Capacity of 
the Tidal Delaware River for Toxic Pollutants; Public Hearings

AGENCY: Delaware River Basin Commission.

ACTION: Notice of Commission determination and public hearings.

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SUMMARY: Notice is hereby given that the Delaware River Basin 
Commission will hold public hearings to receive comments on a 
determination that the assimilative capacity of the tidal Delaware 
River is being exceeded for certain toxic pollutants. This 
determination will authorize the Executive Director to establish 
wasteload allocations for specific point source discharges of these 
pollutants.

DATES: The public hearings are scheduled as follows:
    May 3, 1999 beginning at 1:30 p.m. and continuing until 5:00 p.m., 
as long as there are people present wishing to testify.
    May 5, 1999 beginning at 1:30 p.m. and continuing until 5:00 p.m. 
as long as there are people present wishing to testify; and resuming at 
6:30 p.m. and continuing until 9:00 p.m., as long as there are people 
present wishing to testify.
    May 11, 1999 beginning at 1:30 p.m. and continuing until 5:00 p.m., 
as long as there are people present wishing to testify.

ADDRESSES: The May 3, 1999 hearing will be held in the Second Floor 
Auditorium of the Carvel State Building, 820 North French Street, 
Wilmington, Delaware.
    The May 5, 1999 hearing will be held in the Goddard Conference Room 
of the Commission's offices at 25 State Police Drive, West Trenton, New 
Jersey.
    The May 11, 1999 hearing will be held in the Jefferson Room of the 
Holiday Inn at 400 Arch Street, Philadelphia, Pennsylvania.

FOR FURTHER INFORMATION CONTACT: Susan M. Weisman, Commission 
Secretary, Delaware River Basin Commission, P.O. Box 7360, West 
Trenton, New Jersey 08628. Telephone (609) 883-9500 ext. 203.

SUPPLEMENTARY INFORMATION:

Background and Rationale

    On October 23, 1996 the Delaware River Basin Commission amended its 
Comprehensive Plan, Water Code and Water Quality Regulations concerning 
water quality criteria for toxic pollutants, and policies and 
procedures to establish wasteload allocations and effluent limitations 
for point source discharges to the tidal Delaware River.
    Specifically, water quality criteria for selected toxic pollutants 
were incorporated in the Comprehensive Plan and Article 3 of the Water 
Code and Water Quality Regulations as stream quality objectives. 
Article 4 of the Water Quality Regulations was amended to include 
policies and procedures to be used to establish wasteload allocations 
for those discharges containing pollutants which exceed the stream 
quality objectives and impact the designated uses of the river 
following a Commission determination that the assimilative capacity of 
a zone of the Delaware River is exceeded. These amendments provided a 
mechanism for identifying toxic pollutants which impair aquatic life 
and human health, and developing uniform and equitable wasteload 
allocations for those NPDES discharges to the tidal Delaware River 
which contribute to their impairment. The permitting authorities of the 
Basin states will utilize allocations developed by the Commission to 
establish effluent limitations for NPDES permittees in their 
jurisdiction, as appropriate.
    The subject of the hearings is a proposed determination by the 
Commission that the assimilative capacity of the tidal Delaware River 
(Trenton, NJ to the head of Delaware Bay) is being exceeded for 1,2-
dichloroethane, tetrachloroethene, chronic toxicity and acute toxicity. 
These parameters were selected based upon their mass loading to the 
estuary, minimal interaction with estuary sediments, and the 
availability of calibrated and validated water quality models that 
could be used to develop the wasteload allocations. This determination 
will authorize the

[[Page 8336]]

Executive Director to establish wasteload allocations for continuous 
point source discharges pursuant to Sections 4.30.7A.1. and 
4.30.7B.2.c. of the Commission's Water Quality Regulations.
    Seventy-six continuous point source discharges were considered in 
each of the wasteload allocation exercises, although the number 
included in any allocation varied from 10 to 55. The procedure used to 
develop the wasteload allocations is called Equal Marginal Percent 
Reduction or EMPR. EMPR is a two step process in which a discharge is 
first considered independently of all other discharges to the estuary. 
In this step called the Baseline Analysis, each discharge must meet 
stream quality objectives in and of itself. In the second step called 
Multiple Discharge Analysis, the cumulative impact of all discharges, 
discharging at the baseline loading established during step one, is 
evaluated against the stream quality objectives. If the analysis 
indicates that an objective is exceeded, then the baseline loads of all 
discharges significantly contributing to the violation are reduced by 
an equal percentage until the stream quality objective is met.
    For 1,2-dichloroethane, 11 of 51 discharges were adjusted from 
their initial loading in order to meet the stream quality objectives. 
For tetrachloroethene, seven of 40 discharges were adjusted in order to 
meet the stream quality objectives. For chronic toxicity, ten of the 55 
discharges were adjusted during the baseline analysis portion of the 
wasteload allocation. The multiple discharge analysis portion of the 
procedure will not be implemented for chronic toxicity so that 
additional data on the relationship between the concentration of 
specific chemicals and toxicity of both wastewater and ambient samples 
can be obtained. This portion will be deferred until Phase 2 of the 
Total Maximum Daily Load (TMDL) is completed.
    For acute toxicity, eight of the ten discharges evaluated were 
reduced from their initial wasteload allocation concentration during 
the baseline analysis portion of the allocation. As with chronic 
toxicity, the multiple discharge analysis which will determine the 
total surface area of the estuary assigned to mixing areas will be 
deferred until Phase 2 of the TMDL is completed.
    In accordance with Section 4.30.7B.2.c.5). of the Commission's 
Water Quality Regulations, a document entitled Wasteload Allocations 
for Volatile Organics and Toxicity: Phase 1 TMDLs for Toxic Pollutants 
in the Delaware River Estuary has been prepared which describes the 
process used to develop wasteload allocations for continuous point 
source discharges as part of Phase 1 of a Total Maximum Daily Load for 
selected toxic pollutants for the tidal Delaware River. This document 
is available on the Commission's web site at www.state.nj.us/drbc, or 
by contacting Christopher Roberts, Public Information Officer, at (609) 
883-9500 ext. 205.
    The following supporting documents describing the mathematical 
models used in the process are also available from the Commission:
    Calibration and Validation of a Water Quality Model for Volatile 
Organics and Chronic Toxicity in the Delaware River Estuary.
    Calibration and Validation of the DYNHYD5 Hydrodynamic Model for 
the Delaware River Estuary.
    Development of a Tidal Version of the CORMIX Models for Application 
to Discharges in the Delaware Estuary.
    Copies of these documents may be obtained by contacting Christopher 
Roberts, Public Information Officer at (609) 883-9500, extension 205.
    Persons wishing to testify are requested to notify the Secretary in 
advance. Written comments on the proposed determination should also be 
submitted to the Secretary.
    Delaware River Basin Compact, 75 Stat. 688.

    Dated: February 9, 1999.
Susan M. Weisman,
Secretary.
[FR Doc. 99-4150 Filed 2-18-99; 8:45 am]
BILLING CODE 6369-01-P