On April 25, 2011, EPA Region 9 and Environmental Response Team (ERT) personnel established a mooring point just off Alcatraz Island as a test for the future deployment of the GE Systems LEAKWISE Waverider oil-on-water detection and monitoring system. This system allows remote real-time monitoring for oil sheens. The oil releases appear to come from subsurface contamination near Alcatraz and are thought to be caused by historical oil storage practices. A Civil War era caponier, or battlement, situated on the northeast corner of the island was used for oil storage for decades while the island was under military control and perhaps during the prison era. Oil which soaked into the underlying bedrock leaks periodically and causes episodic oil sheens in San Francisco Bay.
EPA deployed the detector on May 5th and expects to leave it in place for several months. Readings will help EPA and the National Park Service (NPS) make decisions about the amount of intervention appropriate at this historical site. Any oil sheen would be detected by the device and transmitted as a text message. Using an SMS relay service, these text messages are converted into an XML format. This information will help EPA and the NPS understand the frequency and extent of the oil releases and permit rapid response action if necessary.
