Abstract |
The Los Angeles Regional Board identified 10 lakes in the Los Angeles region as impaired by algae, ammonia, chlordane, copper, DDT, eutrophication, lead, organic enrichment/low dissolved oxygen, mercury, odor, PCBs, pH and/or trash and placed them on California's 303(d) list of impaired waters requiring a Total Maximum Daily Load (TMDL) (LARWCQB, 1998). The United States Environmental Protection Agency (USEPA) Region IX subsequently entered into a consent decree with several environmental groups on March 22, 1999 that required development of TMDLs for these waterbody pollutant combinations by March 2012 (Heal the Bay Inc., et al. v. Browner C 98-4825 SBA). To meet the consent decree deadline, USEPA is establishing Total Maximum Daily Loads (TMDLs) in nine of these lakes in the Los Angeles region. For several lakes, USEPA concluded that ammonia, pH, copper and/or lead are currently meeting water quality standards and TMDLs are not required at this time. In other lakes, recent chlordane and dieldrin data indicate additional impairment. |