Toxics

Regulation 2, Rule 5 replaced the District’s Risk Management guidelines on July 1, 2005. This rule provides preconstruction review for potential health impacts from new and modified sources of toxic air contaminants. Toxic emissions are estimated for all sources within a proposed project; if emissions from a proposed project exceed the trigger levels in Table 2-5-1, a Health Risk Screening Analysis (HRSA) is required to determine project risk and risk from each source. Risk standards are:

2-5-301 Best Available Control Technology for Toxics (TBACT) Requirement:

The applicant shall apply TBACT to any new or modified source of TACs where the source risk is a cancer risk greater than 1.0 in one million (10 E-6), and/or a chronic hazard index greater than 0.20.

2-5-302 Project Risk Requirement:

The APCO shall deny an Authority to Construct or Permit to Operate for any new or modified source of TACs if the project risk exceeds any of the following project risk limits:

302.1 A cancer risk of 10.0 in one million (10 E-6).

302.2 A chronic hazard index of 1.0.

302.3 An acute hazard index of 1.0.

The following policies and procedures provide clarification for certain toxics screenings and evaluations.

Manual of Procedures, Vol. II, Engineering Permitting Procedures, Part 4 (New and Modified Sources of Toxic Air Contaminants) - 06/06/2005
Staff Report, Appendix D, Proposed BAAQMD Air Toxics NSR Program Health Risk Screening Analysis Guidelines - 06/06/2005
Guidance for Calculating Maximum Hourly Toxic Air Contaminant Emission Rates - 06/16/2005
Unified TAC List for Public Notice, Schools - 06/11/2007