San Joaquin Valley and South Coast PM2.5 Air Quality Plans

Proposed Partial Approval and Partial Disapproval

U.S. EPA Fact Sheet

Summary

EPA is proposing to partially approve and partially disapprove the fine particulate (PM2.5) air 

quality plans for the San Joaquin Valley and South Coast areas in California. These plans, 

known as the State Implementation Plans (SIPs), are the roadmaps to meeting by 2015 the 

1997 PM2.5 National Ambient Air Quality Standards (NAAQS) set by the U.S. EPA to 

protect public health. 

EPA cannot fully approve the plans because they rely heavily on emissions reductions from 

several State rules that have not been finalized or submitted to EPA for review.

California is a national leader in air pollution controls that protect public health by improving 

air quality. The majority of the emission reductions needed to demonstrate attainment of the 

PM2.5 standards have already been adopted by the California Air Resources Board (CARB) 

and the San Joaquin Valley and South Coast Air Districts. 

We expect that their continuing efforts over the next year will result in the adoption and 

submittal of the controls needed to meet the PM2.5 air quality standards. We are committed to 

working with the agencies to address today’s proposed disapprovals.

These proposed actions will be published in the Federal Register and will include a 60-day 

public comment period from the date of publication. EPA’s Federal Register notices and 

technical support documents contain detailed information on our proposed actions.

Background

The San Joaquin Valley and South Coast areas both violate the 1997 PM2.5 NAAQS. These 

areas have the highest annual PM2.5 levels in the country. PM2.5 can be emitted directly into 

the atmosphere or formed in the atmosphere as a result of various chemical reactionsfrom 

emissions of nitrogen oxides, sulfur dioxide, volatile organic compounds, and ammonia. 

These particles can reach the deepest regions of the lungs. Exposure to particle pollution is 

linked to a variety of significant health problems including damage to lung tissue, cancer and 

premature death. 

Primary sources contributing to PM2.5 and its precursors are diesel trucks, other diesel 

engines, wood burning, agricultural burning, and in the South Coast, ship engines.

According to the San Joaquin Valley and South Coast plans, these areas need approximately 

a 45 percent reduction in emissions from 2005/2006 levels in order to meet the PM2.5

NAAQS.

The State submitted the South Coast Air Quality Management District’s PM2.5 SIP to EPA as 

part of an integrated air quality management plan on November 28, 2007. The State 
submitted the San Joaquin Valley Air Pollution Control District’s PM2.5 SIP on June 30, 

2008. 

Both plans rely on emission reductions from CARB’s mobile source control measures, such 

as the Cleaner In-Use Truck and Bus rule and the Cleaner In-Use Off-Road Equipment Rule, 

which were included in CARB’s 2007 State Strategy, submitted to EPA on November 16, 

2007. These rules are currently being revised by CARB, and have not been submitted to 

EPA for review.

EPA is Proposing to Approve the Following Plan Elements:

Emissions inventories. An emissions inventory is an accounting, by source, of the amount of 

air pollutants discharged into the atmosphere during a given time period. Emission 

inventories are used to help determine significant sources of air pollutants, establish emission 

trends over time and target regulatory actions.

Emissions reductions from rules that have been adopted and submitted, and that EPA has 

approved. The South Coast and San Joaquin Valley Air Districts have adopted rules locally 

that help lower particulate levels, including San Joaquin Valley’s residential wood-burning 

program, gas turbine and open burning rules, and South Coast’s rules controlling emissions 

from solvents, coatings, and space heaters. CARB has adopted requirements for ships, 

consumer products, and on-road vehicle inspection and maintenance programs.

The aggregate commitment to emissions reductions in both plans that are tied to State and 

District rules. 

EPA is Proposing to Disapprove the Following Plan Elements:

Attainment demonstrations: The plans rely heavily on emissions reductions from rules 

including CARB’s In-Use Truck and Bus rule and Cleaner In-Use Off-Road Equipment rule 

that are currently being revised and have not been submitted to EPA. 

 Without these rules, the plans’ attainment demonstrations are missing about a fifth of 

the emissions reductions needed for the areas to achieve the PM2.5 air quality standards.

 Until these rules are submitted to EPA and we have the opportunity to review and act 

on them, the State’s commitment for future emissions reductions is too high and is not 

approvable.

For areas requesting an attainment date after 2010, approval of parts of the plan depend on 

EPA first approving the attainment demonstration and the requested attainment date. These 

parts include the demonstrations of reasonably available control measures (RACM) and 

reasonable further progress (RFP), contingency measures, and motor vehicle emissions 

budgets.

EPA is proposing to find that controls on sources of volatile organic compounds (VOCs) can 

contribute significantly to attainment in the San Joaquin Valley. The current San Joaquin 

Valley plan does not address VOCs and their contribution to PM2.5 formation.
Next Steps

EPA is providing a 60-day public comment period on its proposed actions.

The State and Districts are continuing to adopt and submit rules to EPA. These rules will 

reduce the size of their future commitments and replace them with actual emissions 

reductions. EPA supports these actions.

In April 2011, the State is required to submit a midcourse review of its PM2.5 plans that will 

evaluate its progress towards meeting the PM2.5 standard. This is an opportunity for the State 

to address EPA’s concerns with the current PM2.5 SIPs.

If EPA finalizes today’s partial disapproval, two sanctions clocks start for those parts of the 

plan that are disapproved. 

Offset sanctions: The first sanction, which would begin 18 months after the effective date of 

the disapproval, is an increase in emissions offsets required for new and modified stationary 

sources in the area.

Highway sanctions: The second sanction, which would begins 24 months after the effective 

date of the disapproval, limits approvals and funding of highway projects. 

Sanctions will not be imposed if the State submits and EPA approves a SIP revision that 

corrects the problems we identified.

Final disapproval of the plan would also lead to a “conformity freeze,” which would prohibit 

these areas from receiving additional transportation funds for projects that require a 

transportation plan conformity determination, until the State submits and EPA approves an 

adequate SIP revision addressing the deficiencies. 

EPA is committed to working with the State to resolve today’s proposed disapprovals, to 

advance our joint goals of improved air quality, and to avoid sanctions or transportation 

conformity consequences in the South Coast and San Joaquin Valley areas. 

For More Information : 

http://www.epa.gov/region9/air/actions/ca.html