[Federal Register Volume 61, Number 23 (Friday, February 2, 1996)]
[Notices]
[Pages 3934-3935]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 96-2268]



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ENVIRONMENTAL PROTECTION AGENCY
[ER-FRL-5413-2]


South Bay International Wastewater Treatment Plant Intent To 
Prepare Two Draft Supplemental Environmental Impact Statements (SEISs)

AGENCIES: U.S. Environmental Protection Agency (EPA) U.S. Section, 
International Boundary and Water Commission (IBWC).

ACTION: Notice of Intent to prepare two Supplemental Environmental 
Impact Statements (SEISs) to examine interim disposal options and 
secondary treatment alternatives for the South Bay International 
Wastewater Treatment Plant, San Diego, CA.

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AUTHORITY: In accordance with Section 510 of the Water Quality Act of 
1987, as amended, and Section 102(2)(c) of the National Environmental 
Policy Act (NEPA). EPA and the IBWC have identified a need to prepare 
two SEISs and therefore issue this Notice of Intent pursuant to 40 CFR 
1501.7, 1508.22, 6.404(a), and 6.105(e).

FOR FURTHER INFORMATION AND TO BE PLACED ON THE PROJECT MAILING LIST 
CONTACT: Ms. Elizabeth Borowiec, U.S. EPA, Region 9, 75 Hawthorne 
Street, Mail Code W-2-2, San Francisco, California 94105, (415) 744-
1948.

SUMMARY: In July 1990, the IBWC and Mexico signed Minute 283 which 
outlined a plan for the treatment of renegade sewage flows emanating 
from Tijuana, Mexico and crossing into the United States along the U.S/
Mexican border in San Diego. In the Minute, the two countries agreed to 
construct an international wastewater treatment plant (IWTP) on the 
U.S. side of the border. In May of 1991, EPA and the IBWC issued a 
draft Environmental Impact Statement (DEIS) which examined alternatives 
to implementing the Minute. After receiving public comment on the DEIS, 
a final EIS (FEIS) was issued in February of 1994 recommending the 
construction of a full secondary treatment wastewater treatment plant 
to be located on a 75-acre site just west of San Ysidro, CA near the 
intersection of Dairy Mart and Monument Roads. The FEIS also 

[[Page 3935]]
recommended the construction of the South Bay Ocean Outfall for 
effluent disposal. In May of 1994, the agencies signed the Record of 
Decision (ROD) selecting the recommended alternative in the FEIS.
    The IWTP, also called the South Bay or Tijuana International 
Wastewater Treatment Plant, is designed to treat an average flow of 25 
million gallons per day of wastewater to a secondary level, with the 
capacity to treat an additional 50 million gallons per day to the 
advanced primary level during peak flows.
    Since the issuance of the FEIS and the ROD, the EPA and IBWC have 
decided to prepare two Supplemental Environmental Impacts Statements 
(SEISs) to address proposed project changes. The first SEIS, or Interim 
SEIS, will address, among other things, a proposal to operate the IWTP 
and discharge effluent in the interim period after completion of the 
advanced primary component but before completion of the secondary 
treatment component and/or the South Bay Ocean Outfall. The Interim 
SEIS will also address other issues such as any new information on 
flows from Mexico, de/chlorination impacts, and toxic monitoring data. 
The second SEIS, or Long-Term SEIS, will address a proposal to evaluate 
alternatives to activated sludge as a method for secondary treatment. 
It will also address issues such as any new information concerning 
Mexico's progress in implementing sludge disposal and industrial 
pretreatment programs.

Alternatives

Interim SEIS

1. No Action
    The IWTP would not be activated until the 25 mgd full secondary 
treatment facilities and the South Bay Ocean Outfall (SBOO) are 
completed.
2. Operate the IWTP as an Advanced Primary Facility
    The IWTP would be used for advanced primary treatment and storage 
in primary settling tanks with disposal via the emergency pipeline 
connection to the City of San Diego's Point Loma Wastewater Treatment 
Plant. Treated flows in excess of the capacity of the emergency 
connection (13 mgd) would be returned to Mexico, if possible, and/or 
released to the Tijuana River.
3. Operate the IWTP as an Advanced Primary Facility With Earthen Basin 
Storage for Flow Equalization
    The IWTP would be used for advanced primary treatment with disposal 
via the emergency pipeline connection to the City of San Diego's Point 
Loma Wastewater Treatment Plant. During peak flow periods, the capacity 
of the emergency connection may be exceeded. Those treated flows could 
be stored in an earthen basin until additional flow capacity is 
available in the emergency connection. Once the capacity of the earthen 
basins are exceeded, treated sewage could be returned to Mexico or 
discharged into the Tijuana River.
4. Operate the IWTP With Treated Flows Returned to Mexico for Discharge 
to the Pacific Ocean at Punta Banderas
    The IWTP would be used for advanced primary treatment with 
discharge to the Pacific Ocean at Punta Banderas in Mexico.
5. Operate the IWTP With Disposal Through the SBOO
    The IWTP would be utilized for advanced primary treatment with 
discharge to the Pacific Ocean via the completed South Bay Ocean 
Outfall.
6. Operate the IWTP Utilizing a Phased Disposal Approach
    The IWTP would be utilized for advanced primary treatment with a 
phased disposal approach dependent on flows from Mexico and the 
completion of SBOO. For flows less than 13 mgd, Alternative 2 would be 
the disposal alternative used. For flows above 13 mgd, Alternative 3 
would be used until SBOO is completed. Finally, Alternative 5 would be 
selected once SBOO is on line.

Long Term SEIS

1. No Action
    The IWTP would be constructed for a 25 mgd mechanical secondary 
facility as discussed in the 1994 FEIS and the ROD. Peaks above 25 mgd, 
up to 75 mgd, would receive only advanced primary treatment.
2. Operate the IWTP With Flow Equalization
    The IWTP would be constructed for a 25 mgd mechanical secondary 
IWTP as discussed in the FEIS and ROD, with the addition of flow 
equalization facilities. Flow equalization would allow for flow storage 
of advanced primary effluent during peak hours of the day with 
secondary treatment of these stored flows at off-peak hours. Flow 
equalization facilities would be designed to equalize flows from the 
primary to the secondary treatment facilities to a constant rate of 25 
mgd.
3. Operate the IWTP With an Expansion to the Mechanical Secondary 
Facilities
    As stated in the FEIS and ROD, the mechanical secondary system has 
a maximum capacity of 25 mgd. This alternative would consider expanding 
the mechanical secondary capacity to handle flow peaks of up to 50 mgd 
(i.e., a 2 to 1 peaking factor).
4. Operate the IWTP With an Alternative to Mechanical Secondary 
Treatment
    Alternatives under consideration include ponds (biological 
treatment ponds) and trickling filters.
    4a. Use of trickling filters with a design capacity of 25 mgd. The 
trickling filters would be designed with either a 2 to 1 peaking factor 
or with flow equalization facilities that would equalize peak flow 
rates of up to 75 mgd from the advanced primary treatment facilities to 
a constant rate of 25 mgd to the trickling filters.
    4b. Use of ponds sized to equalize and treat peak flows up to 75 
mgd.
5. Maintain the IWTP at the Advanced Primary Treatment Level
    The IWTP would be built with advanced primary facilities only as 
discussed in the FEIS and ROD (25 mgd average, 75 mgd peak); no 
secondary facilities would be constructed. Advanced primary treated 
effluent would be released to the Pacific Ocean through the SBOO.

SCOPING: Although scoping meetings are not required for SEISs, the EPA 
and the IBWC have held a meeting on August 31, 1995 in San Diego for 
the Interim SEIS. A scoping meeting for the general public regarding 
the Long-Term SEIS is planned for San Diego in February 1996.

PROPOSED DATE OF RELEASE:

Interim SEIS--Draft-Spring 1996, Final-Fall 1996
Long-Term SEIS--Draft-Summer 1997, Final-Winter 1997.

RESPONSIBLE OFFICIALS:

Felicia Marcus, Regional Administrator, U.S. Environmental Protection 
Agency, Region 9
John Bernal, Commissioner, U.S. Section, International Water and 
Boundary Commission.
Anne Norton Miller,
 Deputy Director, Office of Federal Activities.
[FR Doc. 96-2268 Filed 2-1-96; 8:45 am]
BILLING CODE 6560-50-P