Great Basin Unified Air Pollution Control District
Working to achieve and maintain federal, state and local air quality standards
Inyo, Mono and Alpine Counties joined together in 1974 in a joint powers agreement to form the Great Basin Unified APCD, which covers the Great Basin valleys - Air Basin in California.
GBUAPCD's purpose is to enforce Federal, State and local air quality regulations and to ensure that the federal and state air quality standards are met in our district. These standards are set to protect the health of sensitive individuals by restricting how much pollution is allowed in the air. To meet these standards we enforce those federal laws delegated to us, state laws on stationary sources of pollution, and pass and enforce our own regulations as they become necessary.
Major Sources of Air Pollution
Owens Lake is the largest single source of PM-10 in the United States. The Federal Clean Air Act required that the District produce a State Implementation Plan (SIP) in 1997 that detailed how we would control this problem. The District signed an agreement with the City of Los Angeles in 1998 that set a schedule for implementing controls. These controls were approved by USEPA. So far, dust controls have been installed by the DWP on about 19.25 square miles (over 12,000 acres) of the lakebed. The PM-10 levels must be reduced to the federal standard by 2006 or the District will be subject to federal sanctions, which could include withholding of federal highway funds. The District’s 2003 SIP revision (attached) requires a total of 30 square miles to be controlled by the end of 2006, and additional areas if necessary to meet the standard as they are verified. District staff devotes considerable resources to monitoring the dust from Owens Lake and enforcing the proper installation and operation of dust control measures.
Mono Lake also violates the federal PM-10 standard. The State Water Resources Control Board considered this in setting the required Mono Lake level in 1994. The District’s Mono Basin SIP was approved by the State in 1995 and sent to the EPA. The lake has risen about 10 feet since the mid-90s and PM-10 levels at some sites have decreased. The lake level needs to raise approximately nine more feet in order to sufficiently control PM-10 emissions.
Mammoth Lakes has high levels of PM-10 in the winter due to a combination of wood smoke and cinders put on icy roads for traction during the winter. In cooperation with the District, the Town developed an ordinance in 1990 to control both sources. The Mammoth Lakes SIP was submitted to the federal government and it has been approved. Since implementation of the ordinance, PM-10 levels have dropped significantly.
The Coso geothermal development east of Coso Junction on the China Lakes Naval Weapons Center property has the potential to violate the state standard for hydrogen sulfide, but has not yet done so because the standard does not apply on the Naval Weapons Center property. We have worked with the geothermal developers to minimize the emissions from each power plant and well in order to allow full development without a violation of the standard off the base.
