Leaking underground storage tank This one has been in the news for the last 10 months. In 1986 there was a serious leak in an underground storage tank at the site. The company and health officials have been working to clean up the site since that time. It was discovered in January that contaminated soil vapors that have seeped into the soil in the Bridgeport neighborhood next to the station, causing three temporary evacuations. According to the orange county Register, “Four homes were thought to have significant levels of contamination and residents were relocated. After further study, the Orange County Health Care Agency and Arco found there were no immediate health risks and the residents were given clearance to return home in March.” This is an on going event. Below is a map showing the location of the station and monitoring wells.

More Information can be obtained from the following articles: Seal Beach wants changes to Arco gas leak cleanup plan BP/ARCO Sets Schedule for Seal Beach Cleanup Seal Beach, Saying Enough is Enough, Wants BP/ARCO to Remove Contaminated Soil

Petroleum contamination was discovered under the subdivision as a result of a nearby investigation by the State Department of Toxics Substance Control. The department detected benzene levels 100,000 times above the state of California’s standard. Benzene is a natural constituent of crude oil, which can cause serious health effects if someone is exposed to the carcinogen. The long-term exposure to high levels of airborne benzene causes leukemia, a potentially fatal type of cancer. The Carousel neighborhood residents fear the test results and the overall outcome of the suspected contamination could leave their property worthless.

For the full story see: http://latimesblogs.latimes.com/lanow/2010/04/-toxic-soil-lurks-beneath-carson-neighborhood.html The map below is a 1934 USGS Topographic map depicting the Former Shell Oil Tank Farm in Carson Former Shell Oil Tank Farm in Carson as it is shown on parcels

National Pipeline Mapping System