All American Asphalt - AB 2588 and Health Risk Assessment

Recent Updates

  • South Coast AQMD has seen some community reports highlighting large emission differences reported by AAA between 2016 and 2017.

  • The differences are due to calculation methods, and do not represent increases in production or a large change in emissions from year to year.

  • The information displayed by the community accurately reflects data submitted to South Coast AQMD by AAA. This information is available on South Coast AQMD’s FIND website. However, the information displayed by the community does not accurately represent AAA’s emissions and should not be used to draw any conclusions on the emissions coming from the facility until correct information is provided.

    • CARB also relies on data submitted by facilities to South Coast AQMD and does not conduct additional verification or auditing.

  • AAA used various emission factors incorrectly in both 2016 and 2017, resulting in inaccurate emissions estimates.

  • The facility is required to self-report this information using correct methodologies.

  • South Coast AQMD reviews information provided by the facility and discovered the calculation errors and is now requiring a more comprehensive Air Toxics Inventory Report as well as testing of individual equipment to evaluate specific sources to get better information about the facility’s emissions.

  • Once the methodology differences noted in the table below have been corrected, the reported emissions between 2016 and 2017 will look similar as production levels were similar in both years.

  • Potential health impacts depend on the type of pollutant, the amount released and the potency of the chemical, which can vary by many orders of magnitude. After the facility submits the comprehensive Air Toxics Inventory Report and completes the equipment tests, staff will assess whether additional steps are needed to evaluate potential health impacts.

  • Recent community air sampling efforts from South Coast AQMD show that average levels of air toxics at each community monitoring site are within background levels and below long-term health thresholds.

Details regarding the key differences in emissions reports submitted to South Coast AQMD are outlined in the table below.

Emissions Or Throughput  Calendar Year 2016  Calendar Year 2017


Correctly reported using South Coast AQMD ‘default’ emission factor for natural gas combustion in the rotary dryer burners

Incorrectly used South Coast AQMD ‘default’ emission factor that includes ammonia from selective catalytic reduction (SCR) controls for the rotary dryer burners, leading to overestimation of ammonia emissions. The dryer burners are not controlled by SCR. This did not affect other emissions estimates

(arsenic, cadmium,
hex chrome)

Incorrectly assumed additional air pollution control (baghouse) applied to EPA ‘default’ emission factors for the rotary dryer, leading to underestimation of metals emissions. The ‘default’ emission factors already accounted for baghouse controls.

Correctly reported using EPA AP-42 ‘default’ emission factor for the dryer

Benzene and Formaldehyde

Incorrectly assumed air pollution control (baghouse) applied to EPA ‘default’ emission factors for the rotary dryer and silo emissions, leading to underestimation of benzene emissions. Baghouses do not control benzene emissions.

Correctly reported using EPA AP-42 emission factor for the dryer and silos.


AB 2588 and Health Risk Assessment

In 1987, the California legislature adopted the Air Toxics “Hot Spots” Information and Assessment Act (Assembly Bill 2588, or AB 2588). The goal of AB 2588 is to collect emissions data of toxic air contaminants, identify facilities having localized impacts, determine health risks, notify affected individuals, and reduce adverse health risks. The AB 2588 Program includes a process for evaluating hundreds of diverse facilities using a rigorous, multi-tiered scientific analysis of their air toxic emissions on an ongoing basis. Although the process can be lengthy for an individual facility, the process provides a standard, comprehensive approach to ensure that all facilities meet the same requirements. For more information, visit our AB 2588 program page.

The AB 2588 process is not the only mechanism to address air quality concerns about a facility. South Coast AQMD uses a multi-pronged approach which includes emissions reporting, complaint response, compliance and enforcement activities and targeted, local air monitoring to determine near-term and longer-term actions.

There are three types of emissions reports, each with a different level of detail. There are ‘annual emissions reports’ which provide basic emissions data and are required from all facilities. The ‘quadrennial’ report that identifies more detailed air toxics emissions inventory and can be required based on a facility’s annual emissions report. Finally, the ‘Air Toxics Inventory Report,’ which is the most detailed report a facility can provide and is triggered based on results from the previous two reports.

All American Asphalt (AAA) Irvine is required to submit ‘annual emissions reports’ with basic emissions data to South Coast AQMD. Based on the annual emissions report from 2015, AAA exceeded the program screening thresholds and was required to submit a quadrennial air toxics emissions inventory for 2016. The report, submitted in March 2017, was the first time AAA reported information to the AB 2588 program.

After conducting an audit and further evaluation of their quadrennial emissions reports in 2019, South Coast AQMD staff discovered a potential discrepancy and required AAA to submit an Air Toxics Inventory Report (ATIR) for 2016. As part of reporting procedures, facilities must also report the closest worker or residential receptor. For AAA, the closest residential receptor is approximately 2,500 feet and the closest worker receptor is approximately 3,800 feet.

Air Toxic Inventory Report (ATIR)

South Coast AQMD sent a Notice to Prepare an ATIR in February 2020. The facility submitted its ATIR in July 2020—which was within rule requirements. The preliminary ATIR used allowable default emission factors rather than site-specific factors to estimate emissions. Non-site-specific, default emissions factors often result in overestimation of emissions for facilities. South Coast AQMD asked AAA to conduct site-specific source testing to develop a more accurate emissions profile that will be input into their final ATIR. Source testing can take several months due to many factors including preparation, review and approval of protocols, conducting of testing and preparing the source test report.

Source Testing

A source test is a procedure where air samples are collected from a specific emissions source (i.e. piece of equipment or exhaust stack), then analyzed in a laboratory. Prior to conducting the source test, a facility is required to submit information about their source test to South Coast AQMD for approval to ensure proper protocols will be followed (e.g., the test conditions are representative of normal operating conditions, etc.). Additionally, the source test must be conducted by a third-party company that has been certified/approved by South Coast AQMD through our Laboratory Approval Program.

In March 2021, independent source testing contractors conducted a source test to measure emissions from AAA’s crumb rubber/asphalt blending process and the associated air pollution control system with the on-site presence of our experts to ensure the testing was being performed according to the approved protocol. Once source tests are completed and the reported emissions data is reviewed and verified, it will be used to evaluate permit requirements and the results will be made public, excluding any information marked as confidential by the facility. (See also Permitting Update.)  A source test on their rotary dryer is anticipated in July.

Next Steps

The final source test report for the rotary dryer is due to South Coast AQMD in early August for review and approval.  The test report review is extensive and can take some time due to the highly technical nature of the work involved. The agency expects to complete its review of the ATIR by October 2021.

If the finalized ATIR shows the potential that the facility’s emissions could result in health risks above agency risk notification thresholds, South Coast AQMD will require that the facility conduct a Health Risk Assessment (HRA). An HRA is a technical study that evaluates how toxic emissions are released from a facility, how they disperse throughout the community and the potential for those toxic pollutants to impact human health (there is no quantifiable methodology in AB 2588 to evaluate how a facility’s operations affect odors in a community). Should AAA be determined to need an HRA, the facility will have 90 days to submit it to South Coast AQMD following the determination. If the results of the HRA indicates that risks are above notification thresholds, South Coast AQMD will notify the public and if the risk is above the risk reduction thresholds, require that the facility take steps to reduce the risk.

AB 2588 Documents

Emissions Reports: Annual emissions reports and quadrennial emission reports for all facilities are available on the South Coast AQMD FIND webpage, and the AAA Irvine can be found here.

ATIR: Approved ATIRs can be obtained through a Public Records Request

HRA: All approved HRAs are available on the AB 2588 webpage.

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