Attachment 20: SOUTH BAY SPILL PREVENTION AND RESPONSE PLAN

Spill and Transboundary Flow Event Prevention & Response Plan United States International Boundary and Water Commission South Bay International Wastewater Treatment Plant

Prepared by:
Veolia &

USIBWC

October 1, 2024

I.

II.

a.

b.

c.

d.

e.

a.

b.

c.

III.

1.

INSPECTIONS OF SBIWTP

2.

PREVENTATIVE MAINTENANCE OF SBIWTP

1.

DAILY INSPECTIONS OF CANYON COLLECTORS

2.

PREVENTATIVE MAINTENANCE OF CANYON COLLECTORS

3.

INSPECTIONS OF CANYON COLLECTORS DURING EMERGENCY CONDITIONS

i.

RAIN EVENT

ii.

DRY WEATHER TRANBOUNDARY FLOW

4.

MAINTENANCE OF COLLECTORS AFTER WET WEATHER

5.

OTHER PREVENTION MEASURES:

i.

EQUIPMENT

ii.

SANDBAGS

iii.

TRASH NOTIFICATION PROTOCOL

A.

INITIAL RESPONSE PROCEDURES

B.

AFTER SPILL ENDS

C.

SPILL CLEANUP

D.

STEWART’S DRAIN

E.

IV.

1.

PLAN AMENDMENT

2.

POSTING

3.

RECORD KEEPING – LOG MAINTENANCE AND RETENTION OF RECORDS

Appendix A Plan Points of Contact
Appendix B SBIWTP Flow Diagram and Design Capacities
Appendix C Canyon Collectors Description
Appendix D Canyon Collectors Daily Inspection Checklist and SOP Appendix E Trash Accumulation Communications Protocol
Appendix F Stewart’s Drain Prevention and Response Plan Appendix G Spill & Transboundary Flow Report and SOP

I.

INTRODUCTION

The South Bay International Wastewater Treatment Plant (“SBIWTP”) is a 25‐million gallon per day (“MGD”) secondary treatment plant that treats wastewater collected within the City of Tijuana, Mexico and discharges the treated wastewater to the Pacific Ocean through the South Bay Ocean Outfall. The sewer collection system, located in Mexico, is maintained by the Comisión Estatal de Servicios Públicos (CESPT) de Tijuana in the City of Tijuana (“City”). Wastewater collected within Tijuana is received by Sewer Pump Stations #1A B, located within the Cit of Tijuanay. By US/Mexico treaty conditions, a 30-day average of 25 MGD is sent to the SBIWTP, with the remainder being conveyed by Pump Station 1A and 1B to San Antonio de los Buenos, located approximately six (6) Miles south of the US/Mexico border. Conveyance is through a force main and gravity pipeline.
Surface releases of wastewater within Mexico are considered potential sources for contamination of waterways and land areas within the United States. By design, canyon collector structures were erected on the United States side of the US/Mexico border to capture low volume flows in dry weather. During wet weather events, canyon collectors do not operate resulting in transboundary flows leading to the Tijuana River channel and estuary. Canyon collectors are referred to by name as Stewart’s Drain, Silva Drain, Canyon Del Sol, Smuggler’s