The District’s integrated approach to addressing and reducing risks from air toxics consists of three main paths: reducing air toxic emissions from existing stationary sources of emissions; preventing the creation of new or modified stationary sources of significant risk; and finding creative and cooperative methods of reducing risk from emissions sources that the District does not typically regulate. This integrated approach has resulted in dramatic reductions in emissions of air toxics from sources in the San Joaquin Valley. Following are summaries of the main programs implemented by the district to address air toxics in the valley.
The State’s Air Toxics "Hot Spots" Information and Assessment Act (AB 2588, 1987, Connelly) was enacted in September 1987. Under this act, stationary sources are required to report the types and quantities of certain toxic substances their facilities routinely release into the air, pursuant to the Health and Safety Code Section 44360.
The District’s implementation of AB 2588 has minimized health risks to the public associated with the release of air toxic emission from sources located within the San Joaquin Valley. Under this right-to-know law, the District has worked with facilities to quantify air toxic emissions, determine the potential health risk associated with those emissions, and report any risk determined to be significant by the District through written public reports and neighborhood public meetings. Although Hot Spots is primarily a public right-to-know and notification program, the public awareness achieved through the Hot Spots program has led many Valley businesses to voluntarily reduce their toxic emissions to ease community concerns. Additional information can be found on the State’s Air Toxics "Hot Spots" Program website.
To protect public health from the potentially harmful effects of air pollution in California communities, California Air Resource Board (CARB) has developed Airborne Toxic Control Measures (ATCMS) for several source categories, as identified in the California Code of Regulations. Some of the source categories include emissions from on-road and off-road vehicles, dry cleaners, portable engines, and chrome plating operations. A list of required ATCMs can be found on CARB’s Airborne Toxic Control Measures website↗.
The District has implemented numerous rules and requirements for these source types to comply with CARB’s ATCMs and, as a result, have contributed to substantial reductions in TAC emissions in the San Joaquin Valley. For more information on ATCMs and what the District is doing to implement ATCMs into the District’s current regulatory processes, visit the Current District Rules and Regulations webpage.
The Environmental Protection Agency (EPA) developed National Emission Standards for Hazardous Air Pollutants (NESHAP) to regulate the release of air toxic emissions from 189 HAPs that are known or suspected to cause cancer and non-cancer related health impacts.
EPA identified industries that emit these HAPs and established a prioritized list of over 70 source categories for which Maximum Achievable Control Technology (MACT) standards are being be promulgated. These MACT standards apply to major sources of HAPs, defined as sources with emissions greater than 10 tons per year of a single HAP, or 25 tons per year of combined HAPs. For more information on NESHAPS and MACT standards, visit EPA’s website.
The District currently is a delegated authority by EPA to implement and enforce NESHAPs through two mechanisms. First, all major sources of HAPs are required to obtain Title V operating permits from the District. Second, the District is a delegated authority to implement and enforce NESHAPs that are included in District Rule 4002, most recently amended on May 20, 2004.
One goal of District risk management review efforts is to minimize the increase that new and modified stationary sources add to the existing toxic load and any potentially significant public health impacts associated with the release of those airborne toxic emissions. In order to achieve this goal, the District evaluates the health risk of stationary sources as part of the District’s permitting process and engineering evaluation.
Under the District’s Risk Management Policy, Toxic Best Available Control Technology (T-BACT) must be applied to all units that may pose greater than de minimis levels of risk (i.e., a cancer risk greater than one in one million). To reduce TAC emissions for projects that trigger T-BACT requirements, District staff works with applicants to find approvable low-risk project alternatives, such as installing air toxic emissions control devices or limiting the operation of the proposed equipment. More information on the District’s T-BACT requirements can be found in the District’s Risk Management Policy APR 1905.
One of the most effective methods of reducing emissions of air toxics from emissions sources not directly regulated by the District has been the incentive grant programs that have leveraged billions of dollars to reduce emissions from diesel internal combustion engines on trucks, tractors and agricultural irrigation operations; residential wood burning fireplaces; lawn equipment; and on road vehicles. See more on the District’s Grants webpage.
Under its integrated air toxics program, the District has also implemented numerous methods of reducing emissions from mobile sources and other sources of emissions that the District does not have the authority to regulate. For instance, the District developed the first Indirect Source Review rule in the nation, designed to reduce emissions from construction equipment and mobile sources associated with new land use development projects. See more on the District’s ISR webpage.
The California Environmental Quality Act (CEQA) requires public agencies to evaluate environmental impacts from a development project and all feasible alternatives or mitigation measures that can substantially reduce or avoid those impacts. Generally, the main responsibility for satisfying CEQA requirements, or “lead agency” role, falls under the responsibility of city or county planning agencies.
From a health risk perspective, land use decisions are critical to improving and preventing degradation of air quality within the San Joaquin Valley, as land use patterns greatly influence potential exposure of sensitive receptors to sources of air pollution. Under CEQA, land use agencies must evaluate the potential significance of health risks associated with development projects. The District provides support to land use agencies when making air quality impact determinations by assisting in the review of health risk assessments performed for the project. See more on the District’s CEQA webpage.
Assembly Bill 617 (C. Garcia, Chapter 136, Statutes of 2017) addresses air pollution impacts in environmental justice communities. This program requires local air districts and the state Air Resources Board to reduce air pollution in these most impacted communities by implementing the following mandates:
Additional grant funding may also be available to communities determined to have the highest air pollution burden. See more on the District’s AB 617 webpage.
