ARB announces 2007 State Implementation Plan for Ozone
SACRAMENTO - The California Air Resources Board (ARB) today announced its new state strategy to attain the
new federal eight hour air quality standard for ozone.
"The State Implementation Plan (SIP) is the blueprint for how the state will meet the federal eight hour ozone
standard. The plan assures attainment of clean air standards as quickly as possible through technically feasible
and cost-effective measures," said Catherine Witherspoon, ARB Executive Officer.
The strategy announced today will reduce ozone-forming emissions in the South Coast Air Basin (the greater Los
Angeles region) and the San Joaquin Valley by as much as one half between now and 2024. The state strategy combined
with local measures proposed by the South Coast Air Quality Management District (SCAQMD) and the San Joaquin Valley
Air Quality Management District make up the 2007 plan for attaining the federal eight hour ozone standard. The
ozone plan is due to U.S. Environmental Protection Agency (USEPA) by June 15, 2007.
The state's plan for the South Coast Air Basin (the greater Los Angeles area) will reduce photochemical ozone-forming
emissions by 212 tons per day (tpd) in 2024. The proposed strategy builds on existing ARB programs that will reduce
smog forming emissions in the South Coast by 670 tpd in 2024. The South Coast Air Quality Management District is
expected to adopt regional measures that will cut another 32 tpd of ozone-forming emissions.
The San Joaquin Valley plan calls for new measures that will reduce ozone-forming emissions by 68 tons per day
in 2024. Existing State programs will eliminate 473 tpd by 2024. The Valley's air quality agency is proposing its
own measures that will cut an additional 54 tpd in that time period. The plan projects attainment for all other
areas of the state of the federal standard by 2020.
The state strategy will also reduce emissions that form fine particulates (PM-2.5) by approximately 40 percent
in the SCAQMD by 2015. However, the nature of particulate pollution is technically complex. The ARB proposes to
use the remainder of 2007 to refine the science and revisit the particulate strategies for those regions. The federal
PM 2.5 plan is due to USEPA in April 2008.
Mobile source measures are the heart of the ARB strategy with modernization of California's diesel fleets an essential
near-term goal. The measures make up 90 percent of the reductions identified in the SIP. "The legacy fleet
of older, higher polluting trucks, buses, locomotives and off-road equipment will continue to slow our progress
toward cleaner air and currently is our biggest hurdle. Natural turnover is slow for engines designed to last for
decades. Therefore, the state strategy is to focus on programs that will clean up or replace those engines through
a comprehensive package of regulations, incentives and efforts by the goods movement industries as quickly as possible,"
The SIP is a comprehensive strategy designed to attain federal air quality standards as quickly as possible through
a combination of technologically feasible and cost-effective measures. It outlines ARB staff's assessment of how
far adopted regulations will take us towards attainment of federal standards, what new actions can be taken, and
what are the earliest feasible timeframes for meeting those standards. For more information click here.
The Air Resources Board is a department of the California Environmental Protection
Agency. ARB's mission is to promote and protect public health, welfare, and ecological resources through effective
reduction of air pollutants while recognizing and considering effects on the economy. The ARB oversees all air
pollution control efforts in California to attain and maintain health based air quality standards.