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Notice of Intent To Prepare a Supplemental Environmental Impact Statement for Clean Water Act Compliance of the South Bay International Wastewater Treatment Plant, San Diego County, CA

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United States Section, International Boundary and Water Commission.


Notice of intent to prepare a draft Supplemental Environmental Impact Statement (SEIS).


This notice advises the public that pursuant to Section 102(2) (c) of the National Environmental Policy Act of 1969, as amended, the United States Section, International Boundary and Water Commission (USIBWC) proposes to analyze and evaluate the impacts of alternatives for the South Bay International Wastewater Treatment Plant to achieve compliance with the Clean Water Act. The Draft SEIS will evaluate alternatives for treatment of sewage flows from Tijuana, Mexico that cross into the United States along the U.S/Mexican border in San Diego. This notice is being provided as required by the Council on Environmental Quality Regulations (40 CFR 1501.7) and the USIBWC's Operational Procedures for Implementing Section 102 of the National Environmental Policy Act of 1969, published in the Federal Register September 2, 1981 (46 FR 44083-44094) to obtain suggestions and information from other agencies and the public on the scope of issues to be addressed in the Draft SEIS. A public scoping meeting will be held to obtain community input to ensure that all concerns are identified and addressed in the Draft SEIS.


The USIBWC will conduct a public scoping meeting from 6 to 8 p.m. PST on Wednesday, November 12, 2003 at the San Ysidro Middle School, 4345 Otay Mesa Road, San Diego, CA. Full public participation by interested federal, State, and local agencies as well as other interested organizations and the general public is encouraged during the scoping process that will end 60 days from the date of this notice. Public Start Printed Page 60419comments on the scope of the Draft SEIS, reasonable alternatives that should be considered, anticipated environmental problems, and actions that might be taken to address them are requested.

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Comments will be accepted for 60 days following the date of this notice by Mr. Charles Fischer, Environmental Protection Specialist, USIBWC, 2225 Dairy Mart Road, San Diego, California, 92173. Telephone: 619/662-7600, Facsimile: 619/662-7607. E-mail:

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The USIBWC has invited the USEPA to participate as a cooperating agency pursuant to 40 CFR 1501.6, to the extent possible. Other agencies may be invited to become cooperators as they are identified during the scoping process.


Since the 1930s, raw sewage flowing into the United States from Mexico has posed a serious threat to public health and the environment in the South Bay communities of San Diego. Although substantial improvements have been implemented over the last two decades, large volumes of untreated wastewater still flow into the Tijuana River Valley today during the rainy season.

In July 1990, the USIBWC and Mexico signed Treaty 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 secondary wastewater treatment plant (IWTP) on the U.S. side of the border that would treat 25 million gallons per day (mgd) of dry-weather sewage flows.

In a 1994 Final Environmental Impact Statement (FEIS) and Record of Decision (ROD), the USIBWC and the EPA, acting as lead agencies, decided to approve the construction of the South Bay International Wastewater Treatment Plant (SBIWTP) and South Bay Ocean Outfall (SBOO). The SBIWTP is located on a 75-acre site just west of San Ysidro, CA near the intersection of Dairy Mart and Monument Roads. Treated effluent is discharged to the Pacific Ocean through the SBOO, a 4.5-mile long 11-foot diameter pipe completed in January 1999.

Pursuant to the completion of an interim operations supplemental environmental impact statement (SEIS), the EPA and the USIBWC decided to construct the SBIWTP in phases: by first building advanced primary facilities followed later by secondary treatment facilities. The intent of this phased construction was to expedite treatment of up to 25 mgd of untreated sewage from Tijuana, which would otherwise have continued to pollute the Tijuana River and Estuary, and coastal waters in the United States.

Treatment at the SBIWTP was initiated in April 1997 as an advanced primary plant with discharge initially through an emergency connection to the City of San Diego Point Loma treatment facility. In January 1999, the SBIWTP began discharging through the completed SBOO.

After the release of the May 1994 Final EIS and ROD and the decision to construct the SBIWTP in two stages, significant additional information became available and new circumstances occurred which warranted a reconsideration of the best means of achieving the completion of secondary treatment facilities at the SBIWTP. Also as a settlement to a lawsuit which challenged the 1994 FEIS, the USIBWC and EPA decided to prepare a SEIS that examined this new information, and the lawsuit was settled.

In January 1998, the USIBWC and the EPA issued the Draft Long Term Treatment Options SEIS (Draft SEIS), to re-evaluate secondary treatment options for the SBIWTP. In addition, in October 1998, the agencies also issued a supplement to the 1996 Interim Operation SEIS that addressed impacts of the advanced primary treatment. This supplement disclosed new information about the presence of dioxins and acute toxicity in the advanced primary discharge. This new information was incorporated into the Final Long Term Treatment Options Supplemental Environmental Impact Statement (Final SEIS) released in March 1999.

In the 1999 ROD for the Long Term Treatment Options SEIS, the EPA and the USIBWC selected the Completely Mixed Aerated (CMA) Pond System at the Hofer Site as the long-term option to provide secondary treatment of 25 mgd of wastewater at the SBIWTP. However, the construction of these secondary treatment facilities was not funded by Congress and the plant has continued to provide advanced primary treatment.

In February 2001, California's Office of the Attorney General, on behalf of the California Regional Water Quality Control Board, San Diego Region (Regional Board), filed a complaint in U.S. District Court, Southern District of California, alleging violations of the federal Clean Water Act and the California Porter-Cologne Water Quality Control Act. Specifically, the complaint alleged USIBWC's discharge violated the terms of its National Pollutant Discharge Elimination System (NPDES) permit issued by the Regional Board for failing to treat the effluent to secondary standards and for violating other effluent limitations. The matter is now scheduled for trial.

The USIBWC has decided to prepare a Supplemental Environmental Impact Statement to address options/actions to cease violations of the NPDES permit limits either by providing secondary treatment in Mexico pursuant to Pub. L. 106-457; or by some other means, including but not limited to redirecting some or all of the IWTP effluent from California's waters and/or instituting some combination of these options.

Coordination with the U.S. Environmental Protection Agency, California Regional Water Control Board and other government agencies, as required, will take place to ensure compliance with applicable federal and state laws and regulations.

The environmental review of this project will be conducted in accordance with the requirements of NEPA, CEQ Regulations (40 CFR parts 1500-1508), other appropriate federal regulations and the USIBWC procedures for compliance with those regulations. Copies of the Draft SEIS will be transmitted to federal and state agencies and other interested parties for comments and will be filed with the Environmental Protection Agency in accordance with 40 CFR parts 1500 through 1508 and USIBWC procedures.


The Draft SEIS to be prepared will consider a range of alternatives, including the no action alternative, based on issues and concerns associated with the project. The Draft SEIS will identify, describe, and evaluate the existing environmental, cultural, sociological and economical, and recreational resources; and evaluate the impacts associated with the alternatives under consideration. Significant issues that have been identified to be addressed in the Draft SEIS include, but are not limited to, impacts to water resources, water quality, cultural and biological resources, and human health effects.

The Draft SEIS will evaluate eight alternatives, as described herein:

1. No Action

Operation of IWTP as an advanced primary facility would continue with discharge to the SBOO until secondary treatment facilities are constructed. Start Printed Page 60420

2. Pub. L. 106-457—Secondary Treatment Facility in Mexico

Operation of IWTP as an advanced primary facility would continue with 25 mgd of primary treated effluent sent to a Secondary Treatment Facility to be constructed in Mexico. Treated effluent would be discharged through the SBOO. Facilities in the U.S. would include: a pump station located on the SBIWTP site; a force main extending from the pump station across the international border to the site of the Secondary Treatment Facility in Mexico; and, a return flow pipeline from the treatment facility to connect with the SBOO.

3. Operate the IWTP with Treated Flows Returned to Mexico for Discharge to Pacific Ocean at Punta Bandera

Operation of IWTP as an advanced primary facility would continue with conveyance of the treated effluent to Mexico via primary effluent return connection (PERC) conveyance/pumping facilities at the SBIWTP and existing conveyance/pumping facilities in Tijuana. If effluent does not enter the San Antonio de los Buenos WWTP, it would be discharged to the surf at a point approximately 5 miles south of the U.S. border at Punta Bandera.

4. Operate the IWTP With Treated Flows Returned to Mexico for Discharge to Pacific Ocean South of Punta Bandera

ITWP would continue to be used for advanced primary treatment with discharge of treated effluent to the Pacific Ocean at a point approximately one mile south of Punta Bandera (approximately 6 miles south of U.S. border).

5. Operate IWTP With City of San Diego Connection

Operation of IWTP as an advanced primary facility would continue but with a total of 15 mgd of advanced primary treated effluent sent to the City of San Diego's Southbay Water Reclamation Plant (SBWRP) for secondary treatment via a new connection with discharge of treated effluent through SBOO. The IWTP would send 10 mgd of screened effluent to the City's Point Loma Wastewater Treatment Plant for secondary treatment via the City's South Metro Interceptor.

6. Operate the IWTP With Treated Flows To send to Mexico and SBWRP

This alternative would be the same as Alternative 5 but instead of sending 10 mgd of screened effluent to Point Loma WWTP, 10 mgd of primary treated effluent would be returned to Mexico for discharge to the Pacific Ocean at Punta Bandera.

7. Completely Mixed Aeration (CMA) Ponds (i.e., Secondary Treatment) at the IWTP

As evaluated in the 1999 FEIS and ROD, a CMA pond system would be constructed at the IWTP to provide secondary treatment.

8. IWTP Closure/Shutdown

The IWTP would be closed as a result of lawsuit resulting from SBIWTP's noncompliance with Clean Water Act. Mexico's current pumping, conveyance, and treatment facilities would be used to handle projected sewage flows.

Availability of the Draft SEIS

The USIBWC anticipates the Draft SEIS will be made available to the public by August 2004.

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Dated: October 14, 2003.

Mario Lewis,

Legal Advisor.

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[FR Doc. 03-26620 Filed 10-21-03; 8:45 am]