New Substances Proposed to be Added to AB 2588

Jan 29, 2020 | Air Quality

The California Air Resources Board (CARB) is in the process of amending the Assembly Bill (AB) 2588 Air Toxics “Hot Spots” Emission Inventory Criteria and Guidelines (EICG) and is soliciting support from the Scientific Review Panel (SRP) in reviewing proposed updates to the chemical substances list in Appendix A of the regulation. The proposed Appendix A-I to A-III list of toxic air contaminants (TACs) includes over 800 new substances. The SRP’s review of this list will provide instructive feedback to CARB as they move forward with revisions to the EICG. Appendix A was last updated in 2007.

The Air Toxics “Hot Spots” Information and Assessment Act of 1987 (AB 2588) was enacted in September 1987. Under this regulation, stationary sources are required to report the types and quantities of toxic substances their facilities routinely release into the air. Emissions of interest include those that result from the routine operation of a facility or that are predictable, including but not limited to continuous and intermittent releases and process upsets or leaks.

The goals of AB 2588 are to collect emissions data, to identify facilities having localized impacts, to ascertain health risks, and to notify nearby residents of significant risks. In September 1992, the “Hot Spots” Act was amended by Senate Bill (SB) 1731 to address the reduction of significant risks. The bill requires that owners of significant risk facilities reduce their risks below the level of significance.

The current Appendix A list of TACs is broken up into three categories (I, II, and III) and a subcategory (carcinogen). Category I is required to be quantified, Category II is required to be reported if produced, used, or present, and Category III need not be reported unless manufactured. Aside from the new substances, the proposed Appendix A has the same three categories with the same requirements. The new list, however, would have eight subcategories:

  • Carcinogens;
  • Developmental and reproductive toxicants;
  • Pesticides;
  • Metals;
  • Other inorganics;
  • Pharmaceuticals;
  • Neurotoxins; and
  • “Other,” which includes chemicals with diverse health effects.

The proposed EICG will provide direction and criteria to facilities on how to compile and submit air toxics emissions data as required under CARB’s “Hot Spots” program. Under the current and the new EICG, air districts determine the methodology that industries are required to use to report TACs. Generally, TACs must be reported to the air district or updated every 4 years, at which time the air district “prioritizes” an emitter; if the priority is high, then the emitter must quantify the air toxics emissions and may be required to perform a health risk assessment (HRA). Once CARB approves the new Appendix A list, a facility that knows it manufactures or emits any of these substances must report it in its air toxics report to the air district.

For more information on the proposed amendments, visit CARB’s website.

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