The San Francisco census tract that includes Treasure Island extends far into San Francisco Bay and includes a tip of Alameda Island. Yerba Buena and Treasure islands together have a land area of 576.7 acres (233.4 ha) with – in 2010 – a total population of 2,500. Treasure Island is connected by a 900 ft (270 m) causeway to Yerba Buena Island, which in turn has on- and off-ramps to Interstate 80 on the San Francisco–Oakland Bay Bridge. The island has a marina and a bikeway connecting to the newly completed Eastern span replacement of the San Francisco–Oakland Bay Bridge. Raised walkways circumscribe nearly the entire island along five streets (Avenue of the Palms, Perimeter Road, Avenue N, Pan American World Airways Esplanade and Clipper Cove Way, formerly known as 1st Street).
Cleanup crews spent several weeks cleaning the island’s coast from the 2007 Cosco Busan oil spill just a few hundred yards from Treasure Island, and the Navy sold the island to the city for $108 million as part of a redevelopment project. The Federal government still maintains an active presence on 40 acres (16 ha) occupied by the United States Department of LaborJob Corps (not part of the redevelopment). The Job Corps moved in and took over 40 acres (16 ha) and 13 building facilities just after the US Navy vacated the island. The Administration Building (Bldg. 1) and Hall of Transportation (Bldg. 2) were listed in the National Register of Historic Places in 2008. On June 8, 2011, the San Francisco Board of Supervisors approved new neighborhood development for 19,000 people over the next 20–30 years by Wilson Meany Sullivan, Lennar Urban, and Kenwood Investments. The 2012-2014 US$1.5 billion Treasure Island Development project for up to 8,000 new residences, 140,000 sq ft (13,000 m²) of new commercial and retail space, 100,000 sq ft (9,300 m²) of new office space, 3 hotels, new Fire station and 300 acres (120 ha) of parks. The island’s gas station pumps and canopy were also removed (the island has a high risk of soil liquefaction and tsunami damage in an earthquake). All island natural gas, electricity, sewer and water utilities are serviced by the San Francisco Public Utilities Commission. By December 2010, Navy contractors had removed 16,000 cubic yards (12,000 m³) of contaminated dirt from the site, “some with radiation levels 400 times the Environmental Protection Agency’s human exposure limits for topsoil.” The contaminated dirt is to be replaced by dirt removed during construction of the fourth Caldecott Tunnel bore. In April 2013, caesium-137 levels three times higher than previously recorded were found (the island hosted “radioactive ships from Bikini Atoll atomic tests and [was] a major education center training personnel for nuclear war” – the USS Pandemonium (PCDC-1) mockup had begun nuclear training in 1957.
