ARTICLE 4. Control of Toxic Air Contaminants [39665. - 39669.]

Cal. Health and Safety Code - HSC 4.

in effect

Cal. Health and Safety Code - HSC § 39665. Section 39665.

(a) Following adoption of the determinations pursuant to Section 39662, the executive officer of the state board shall, with the participation of the districts, and in consultation with affected sources and the interested public, prepare a report on the need and appropriate degree of regulation for each substance which the state board has determined to be a toxic air contaminant. (b) The report shall address all of the following issues, to the extent data can reasonably be made available: (1) The rate and extent of present and anticipated future emissions, the estimated levels of human exposure, and the risks associated with those levels. (2) The stability, persistence, transformation products, dispersion potential, and other physical and chemical characteristics of the substance when present in the ambient air. (3) The categories, numbers, and relative contribution of present or anticipated sources of the substance, including mobile, industrial, agricultural, and natural sources. (4) The availability and technological feasibility of airborne toxic control measures to reduce or eliminate emissions, the anticipated effect of airborne toxic control measures on levels of exposure, and the degree to which proposed airborne toxic control measures are compatible with, or applicable to, recent technological improvements or other actions which emitting sources have implemented or taken in the recent past to reduce emissions. (5) The approximate cost of each airborne toxic control measure, the magnitude of risks posed by the substances as reflected by the amount of emissions from the source or category of sources, and the reduction in risk which can be attributed to each airborne toxic control measure. (6) The availability, suitability, and relative efficacy of substitute compounds of a less hazardous nature. (7) The potential adverse health, safety, or environmental impacts that may occur as a result of implementation of an airborne toxic control measure. (8) The basis for the finding required by paragraph (3) of subdivision (b) of Section 39658, if applicable. (c) The staff report, and relevant comments received during consultation with the districts, affected sources, and the public, shall be made available for public review and comment at least 45 days prior to the public hearing required by Section 39666.

Cal. Health and Safety Code - HSC § 39666. Section 39666.

(a) Following a noticed public hearing, the state board shall adopt airborne toxic control measures to reduce emissions of toxic air contaminants from nonvehicular sources. (b) For toxic air contaminants for which the state board has determined, pursuant to Section 39662, that there is a threshold exposure level below which no significant adverse health effects are anticipated, the airborne toxic control measure shall be designed, in consideration of the factors specified in subdivision (b) of Section 39665, to reduce emissions sufficiently so that the source will not result in, or contribute to, ambient levels at or in excess of the level which may cause or contribute to adverse health effects as that level is estimated pursuant to subdivision (c) of Section 39660. (c) For toxic air contaminants for which the state board has not specified a threshold exposure level pursuant to Section 39662, the airborne toxic control measure shall be designed, in consideration of the factors specified in subdivision (b) of Section 39665, to reduce emissions to the lowest level achievable through application of best available control technology or a more effective control method, unless the state board or a district board determines, based on an assessment of risk, that an alternative level of emission reduction is adequate or necessary to prevent an endangerment of public health. (d) Not later than 120 days after the adoption or implementation by the state board of an airborne toxic control measure pursuant to this section or Section 39658, the districts shall implement and enforce the airborne toxic control measure or shall propose regulations enacting airborne toxic control measures on nonvehicular sources within their jurisdiction which meet the requirements of subdivisions (b), (c), and (e), except that a district may, at its option, and after considering the factors specified in subdivision (b) of Section 39665, adopt and enforce equally effective or more stringent airborne toxic control measures than the airborne toxic control measures adopted by the state board. A district shall adopt rules and regulations implementing airborne toxic control measures on nonvehicular sources within its jurisdiction in conformance with subdivisions (b), (c), and (e), not later than six months following the adoption of airborne toxic control measures by the state board. (e) District new source review rules and regulations shall require new or modified sources to control emissions of toxic air contaminants consistent with subdivisions (b), (c), and (d) and Article 2.5 (commencing with Section 39656). (f) Where an airborne toxic control measure requires the use of a specified method or methods to reduce, avoid, or eliminate the emissions of a toxic air contaminant, a source may submit to the district an alternative method or methods that will achieve an equal or greater amount of reduction in emissions of, and risk associated with, that toxic air contaminant. The district shall approve the proposed alternative method or methods if the operator of the source demonstrates that the method is, or the methods are, enforceable, that equal or greater amounts of reduction in emissions and risk will be achieved, and that the reductions will be achieved within the time period required by the applicable airborne toxic control measure. The district shall revoke approval of the alternative method or methods if the source fails to adequately implement the approved alternative method or methods or if subsequent monitoring demonstrates that the alternative method or methods do not reduce emissions and risk as required. The district shall notify the state board of any action it proposes to take pursuant to this subdivision. This subdivision is operative only to the extent it is consistent with the federal act.

Cal. Health and Safety Code - HSC § 39667. Section 39667.

Based on its determinations pursuant to Section 39662, the state board shall consider the adoption of revisions in the emission standards for vehicular sources and regulations specifying the content of motor vehicle fuel, to achieve the maximum possible reduction in public exposure to toxic air contaminants. Except for regulations affecting new motor vehicles which shall be based upon the most advanced technology feasible for the model year, regulations developed pursuant to this section shall be based on the utilization of the best available control technologies or more effective control methods, unless the state board determines, based on an assessment of risk, that an alternative level of emission reduction is adequate or necessary to prevent an endangerment of public health. Those regulations may include, but are not limited to, the modification, removal, or substitution of vehicle fuel, vehicle fuel components, or fuel additives, or the required installation of vehicular control measures on new motor vehicles.

Cal. Health and Safety Code - HSC § 39668. Section 39668.

(a) The state board shall, on or before January 1, 1989, prepare a written report on the availability and effectiveness of toxic air contaminant monitoring options in consultation with the Scientific Review Panel on Toxic Air Contaminants, the districts, the Department of Food and Agriculture, and the State Department of Health Services. In preparing the report, the state board shall conduct at least one public workshop. The report shall include, but not be limited to, all of the following: (1) An evaluation of existing toxic air contaminant monitoring capacity and assessment capabilities within the state, including, but not limited to, existing monitoring stations and equipment of the state board and of the districts. (2) An analysis of the available options for monitoring and assessing current levels of exposure to identified and all potential toxic air contaminants in urban areas of the state, taking into consideration the technical feasibility and costs of these monitoring options. The report shall evaluate the extent to which the establishment of additional monitoring capacity is appropriate and feasible to facilitate the identification and control of toxic air contaminants. (3) A list of all substances or classes of substances addressed by the state board pursuant to paragraph (2), including, but not limited to, a discussion of the appropriateness and availability of monitoring for those substances or classes of substances. (4) An analysis of the feasibility and costs of establishing an indoor toxic air contaminant monitoring program to facilitate the implementation of Section 39660.5. (b) Based on the findings in the report prepared pursuant to subdivision (a), the state board shall develop, by July 1, 1989, in conjunction with the districts, guidelines for establishing supplemental toxic air contaminant monitoring networks to be implemented by the districts. The board shall develop the guidelines only to the extent that it determines, pursuant to paragraph (2) of subdivision (a), that establishing additional monitoring capacity is appropriate and feasible. (c) The guidelines established pursuant to subdivision (b) shall include a priority list for establishing and implementing the supplemental toxic air contaminant monitoring networks. The state board shall give priority to that supplemental monitoring capacity it determines to be most needed to identify and control toxic air contaminants. The state board shall allocate to districts, in the priority order included in the guidelines, state funds provided in subdivision (b) of Section 3 of the act adding this section and in subsequent Budget Acts for establishing and implementing the supplemental toxic air contaminant monitoring networks. The state board shall allocate state funds to the districts, upon appropriation by the Legislature, on a 50 percent matching basis, and shall not provide state funds for the supplemental toxic air contaminant monitoring program established by Section 40715 to any district in excess of district funds allocated by the district in establishing and implementing the supplemental monitoring networks created pursuant to Section 40715. (d) The state board shall request in its annual budget sufficient state funds, in addition to those provided in subdivision (b) of Section 3 of the act adding this section, to match, on a 50 percent basis, those district funds allocated by the districts for establishing and implementing the supplemental monitoring program specified in the guidelines adopted pursuant to subdivision (b).

Cal. Health and Safety Code - HSC § 39669. Section 39669.

Nothing in this chapter is a limitation on the authority of the state board or a district to implement and enforce an airborne toxic control measure adopted prior to January 1, 1993.

Source: CA Legislative Counsel Bulk DataURL: https://downloads.leginfo.legislature.ca.gov/pubinfo_2025.zipFetched: 6/27/2026