California Air Resources Board 2006 Almanac (web) Chapter 5 Table 5-11 Statewide Chromium (Hexavalent) County Air Basin tons/year Percent Kern Mojave Desert 0 19% San Diego San Diego 0 16% San Bernardino Mojave Desert 0 6% Tuolumne Mountain Counties 0 6% Los Angeles South Coast 0 5% Imperial Salton Sea 0 4% Fresno San Joaquin Valley 0 3% Kern San Joaquin Valley 0 3% Sonoma North Coast 0 3% Orange South Coast 0 3%