Featured Story: Tosco-Rodeo Oil Refinery
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EPA's Pacific Southwest regional office is supporting an innovative project to make real-time air pollution monitoring data from the Tosco-Rodeo Oil Refinery, located in Contra Costa County, Calif., available to the public. Project partners are making recommendations on how to present this data to local residents and officials in useful and accessible ways. Partners will be continuing their efforts to assure publication of this data on the Internet. |
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Tosco-Rodeo is a large oil refinery located about 25 miles northeast of San Francisco. It is situated between the communities of Rodeo and Crockett, with a school and public housing on the south fenceline, the I-80 freeway to the east, and San Pablo Bay to the west.
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The refinery is located on the eastern shore of San Pablo Bay |
In 1994, an estimated 200 tons of the toxic alkaline compound Catacarb® leaked out of the refinery and into the air of surrounding communities. The leak continued for two weeks before Unocal, the refinery's owner at the time, publicly reported it. The incident heightened neighbors' fears of air emissions from the refinery.
Fenceline Monitoring
Local concerns led Contra Costa County to require additional air monitoring at the refinery in conjunction with Tosco's request for a land use permit. The County required Tosco to work with community members to design and install a monitoring network that could simultaneously measure and report toxic air pollutants at the refinery's fenceline.
Most urban areas monitor six major air pollutants (ozone, particulates, sulfur dioxide, carbon monoxide, nitrogen oxides, and lead). Many facilities monitor emissions from individual smoke stacks and other units. By contrast, Tosco's remote sensing equipment monitors for the presence of 38 pollutants in the air all along the fenceline (as opposed to individual points). Many of the air pollutants monitored are hazardous, as defined by Section 112 of the Clean Air Act,
and several are considered major air pollutants.
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Photo by Christy Shake |
The technological advances of the system have far outpaced the ability to make full use of the quantity of data generated by the monitors. One of the key goals of this project is to present this data to local residents and officials in useful ways to get a better understanding of the air pollution exposures and risks.
Assessing the Technology
The Tosco Fenceline project has been assessing the monitoring technology and attempting to translate raw data into useful and accessible information. In 1999, EPA's Environmental Monitoring for Public Access and Community Tracking Program (EMPACT) awarded three $50,000 grants to help project partners achieve this goal. The effort examined:
- levels of air pollution recorded
- the accuracy and reliability of the data
- what is known and not known about likely health effects
- how information on air toxics data and health effects could responsibly be presented to the public
Using Tosco fenceline data together with information from other local community-based monitoring projects and EPA efforts, community residents will be able to gain a fuller understanding of air pollution exposures and risks. Project partners have made recommendations for how to best present the monitoring data to improve community knowledge and access.
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Photo by Jim Gallagher, Contra Costa Health Services |
Project Partners
The principal partners in this project include Contra Costa County, Communities for a Better Environment (CBE), and the Shoreline Environmental Alliance (SEA). They are supported by a Working Group composed of representatives from the Bay Area Air Quality Management District (BAAQMD) and several state agencies, including the California Dept. of Health Services and the Office of Environmental Health Hazard Assessment.
Various EPA offices also participated, including EPA's research office, enforcement office, and quality assurance staff. The Working Group also includes a representative from the Tosco-Rodeo refinery.
About Air Toxics
More information is available about air toxics, including health and ecological effects, data and maps, technical resources, and regulations.
Opening photo by Christy Shake
For more information:Please contact EPA's Wienke Tax at wienke.tax@epa.gov