"Death Zones" in San Diego Bay

Report finds significant contamination of San Diego Bay sediments

by Carolyn Chase
he State Water Resources Control Board and the National Oceanic and Atmospheric Administration (NOAA) have released their Final Report on Chemistry, Toxicity, and Benthic (at the bottom) Community Conditions in Sediments of the San Diego Bay Region. This study of three estuaries in the San Diego Region San Diego Bay, Mission Bay, and the Tijuana Estuary was a multi-year, multi-faceted, multi-agency $500,000 effort. The project, funded through the State's Bay Protection and Toxic Cleanup Program, had a dual purpose: 1) characterize the general state of sediments in the Bay, and 2) find toxic sediment hot spots. A summary of the report's findings has been released by the Environmental Health Coalition (EHC) along with recommended actions to clean up and prevent future contamination of San Diego Bay.

The report clearly shows that the most toxic areas are located adjacent to 32nd Street Naval Station, NASSCO, Southwest Marine, Continental, Campbell Shipyards, and the Navy Submarine Base. Diane Takvorian, EHC Executive Director, stated, "It is no coincidence that the bay sediments are most contaminated where the most polluting industries are operating. This speaks to the need for immediate cleanup and stricter operating standards for those industrial and Naval operations that pollute San Diego Bay."

Another toxic hot spot was found at the foot of the Laurel Street storm drain where chlordane, a persistent pesticide, is suspected. This is a storm drain that drains a large urban area and may include runoff from the airport and adjacent industries.

Outlining EHC's recommended plan of action, Laura Hunter, Director of EHC's Clean Bay Campaign stated, "This is the most important study that has been done on San Diego Bay. The toxic hot spot areas in the Bay are functioning as 'death zones' for marine life. If not removed, these chemicals bioaccumulate in fish and will continue to threaten human health and the environment for hundreds of years. Clean up of these contaminated sediments needs to be a priority." EHC's recommendations for action include emergency cleanup for the most toxic sites, a fish tissue study to assess the safety of fish consumption, stricter discharge prohibitions for industries and Navy facilities located next to the most toxic areas, and establishment of pollution prevention programs for all discharges to the bay so that this problem does not recur in the future.

Since the report was released in April, the response has been lackluster. EHC presented the Regional Board with a variety of options suggesting that anything would be better than nothing yet they did nothing.

What could they do? According to Hunter, "The Board has the power to fine polluters. As just one example, the Port of San Diego has had more than 180 violations and there have been no fines. They've done nothing except say they'll look into it. How many years do you have to look into it before requiring cleanup? This report shows unequivocally that we should be taking action."

What's the public to do?

Write to your Senate representative (Sacramento, CA 95814) and ask their position on AB 1479: Extension of the Bay Protection and Toxic Cleanup Program. Ask them to support it.

Write to Tim Kelly, Chair, RWQCB, 9771 Clairemont Mesa Blvd, Suite A, San Diego CA 92124. Tell him you want them to take immediate and aggressive action to implement cleanup of San Diego Bay's polluted zones.

EHC's recommendations for action are based on the following significant findings of the sediment study:

Bay sediments have significant contamination of mercury, copper, zinc, poly-aromatic hydrocarbons (PAH), chlordane, and PCBs.
Over 56 percent of the bay sediment is estimated to be acutely toxic to marine organisms.
As much as 74 percent of the area exhibited chronic toxicity impacts to marine organisms.
There are four sites designated as having the highest priority due to high toxicity and degradation of marine life. They are: the Seventh Street Channel (Naval Station), two commercial shipyards, and the outflow of the Laurel Street storm drain. The most toxic sites in the entire San Diego region were in the Seventh Street Channel.
20 stations in six general areas were rated as moderate, meaning that they demonstrated toxicity and elevated chemistry and/or degraded marine life.
Several chemicals of concern at elevated levels in the Bay are known to biomagnify and bioconcentrate in tissue of marine species. These are of special concern for human health.
The study represents the best-case scenario due to very conservative assumptions used. The results narrowed concern from 164 suspected sites to 4 critical sites and 6 areas that need immediate attention.
Of 63 Bay stations sampled for benthic communities, over half were degraded.
San Diego Bay ranked seventh highest for PCB contamination in the country.
Compared to other West Coast bays, San Diego Bay had the highest concentrations of metals, PAHs, and chlorinated hydrocarbons and was most toxic in two out of three toxicity tests.
Compared with other East Coast bays, San Diego Bay had higher overall toxicity.

A copy of the full report is available at EHC offices at 1717 Kettner, Suite 100, San Diego. Excellent maps are available of the toxic hot spot locations in the Bay.

Carolyn Chase is Chairperson of the Waste Management Advisory Board of the City of San Diego, a board member and Executive Director of San Diego Earth Day and a member of the Executive Committee of the San Diego Chapter of the Sierra Club