"Hot Spots" Information and Assessment Act (AB2588) 

The 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 substances their facilities routinely release into the air. Emissions of interest are 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 the Air Toxics "Hot Spots" Act are to collect toxic emissions data, to identify facilities potentially having localized health risk impacts, to ascertain the extent of the health risks, and to notify nearby residents of significant risks. In September 1992, the "Hot Spots" Act was amended by Senate Bill (SB) 1731 (Calderon) 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 Act requires that toxic air emissions from stationary sources (facilities) be quantified and compiled into an inventory according to criteria and guidelines developed by the ARB, that each facility be prioritized to determine whether a risk assessment must be conducted, that the risk assessments be conducted according to methods developed by the Office of Environmental Health Hazard Assessment (OEHHA), that the public be notified of significant risks posed by nearby facilities, and that emissions which result in a significant risk be reduced. Since the amendment of the statute in 1992 by enactment of SB 1731, facilities that pose a potentially significant health risks to the public are required to reduce their risks, thereby reducing the near-source exposure of Californians to toxic air pollutants. Owners of facilities found to pose significant risks by a district must prepare and implement risk reduction audit and plans within 6 months of the determination.

The Act was further modified by AB 564, chaptered on September 19, 1997. The passage of AB 564 amended the Hot Spots statute in several ways, including adding provisions that: exempt specified low priority facilities from further compliance with the Hot Spots program; reinstate exempted facilities if specified criteria are met; specify an alternative evaluation process for facilities subject to district permit programs; and other changes to exempt specified facilities from further compliance with the Hot Spots Program.

In summary, the Air Toxics "Hot Spots" Act establishes a formal air toxics emission inventory risk quantification program for districts to manage. The goal of the Air Toxics "Hot Spots" Act is to collect emission data indicative of routine predictable releases of toxic substances to the air, to identify facilities having localized impacts, to evaluate health risks from exposure to the emissions, to notify nearby residents of significant risks, and, due to SB 1731, reduce risk below the determined level of significance. Information gathered from this program has complemented the ARB's existing toxic air contaminant program by locating sources of substances that were not under evaluation and by providing exposure data needed to develop regulations for control of toxic pollutants. Additionally, the program has been a motivating factor for facility owners to voluntarily reduce their facility's toxic emissions.

For more information, explore CARB's Overview of the Air Toxics "Hot Spots" Information and Assessment Act or more resources at  ARB's website: https://ww2.arb.ca.gov/

NCUAQMD Air Toxics "Hot Spots" AB 2588 Program

The NCUAQMD implements the AB 2588  Air Toxics "Hot Spots" Information and Assessment Act Program for Humboldt, Del Norte, and Trinity Counties. 

The Hot Spots Act requires facilities that are ranked as a high priority  (see Prioritization) to submit a health risk assessment (HRA) to the District.  A risk assessment, as defined under the Air Toxics "Hot Spots" Act, includes a comprehensive analysis of the dispersion of hazardous substances into the environment, the potential for human exposure, and a quantitative assessment of both individual and population-wide health risks associated with those levels of exposure. The risk assessments submitted by the facilities are reviewed by OEHHA and approved by the District. In addition, the district may require facilities in the intermediate and low-priority categories to also submit a health risk assessment.

Annual Report

An implementation status report for the District's Air Toxics Control Program is prepared annually. The report includes a summary of the prioritization and health risk assessment process, the current reporting and evaluation status for facilities being tracked under the program, and the existing and proposed control measures to reduce the emissions of toxic air contaminants. Each year, the District holds one or more public hearings to present the AB 2588 Toxic "Hot Spots" Annual Report and discuss its content and significance. The final report is disseminated to county boards of supervisors, city councils, and local health officers.

Annual Reports on the AB 2588 Air Toxics "Hot Spots" Program

 AB 2588 Air Toxics "Hot Spots" 2024  Annual Report of 2023 Emissions