2014-069 - Final Environmental Impact Report No. 2014-01

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HARBOR BLVD. MIXED USE TRANSIT CORRIDOR PLAN FINAL FIR CITY OF SANTA ANA 5. Environmental Analysis AIR QUALITY By the last update to the TAC list in December 1999, CARB has designated 244 compounds as TACs (CARB 1999). Additionally, CARB has implemented control measures for a number of compounds that pose high risks and show potential for effective control. The majority of the estimated health risks from TACs can be attributed to relatively few compounds, the most important being DPM. In 1998, CARB identified diesel particulate matter as a TAC. Previously, the individual chemical compounds in diesel exhaust were considered TACs. Almost all diesel exhaust particle mass is 10 microns or less in diameter. Because of their extremely small size, these particles can be inhaled and eventually trapped in the bronchial and alveolar regions of the lung. Multiple Air Toxics Exposure Study (MATES) III In 2000, SCAQMD conducted a study on ambient concentrations of TACs and estimated the potential health risks from au toxics. The results showed that the overall risk for excess cancer from a lifetime exposure to ambient levels of au toxics was about 1,400 in a million. The largest contributor to this risk was diesel exhaust, accounting for 71 percent of the au toxics risk. In 2008, SCAQMD conducted its third update to its study on ambient concentrations of TACs and estimated the potential health risks from au toxics. The results showed that the overall risk for excess cancer from a lifetime exposure to ambient levels of au toxics was about 1,200 in one million. The largest contributor to this risk was diesel exhaust, accounting for approximately 84 percent of the au toxics risk (SCAQMD 2008a). Excess cancer risk is 742 to 1,035 in a million in the vicinity of the Harbor Boulevard Mixed Use Transit Corridor Plan area (SCAQMD 2008a). Regulatory Setting AAQS have been promulgated at the local, state, and federal levels for criteria pollutants. The project site is in the SoCAB and is subject to the rules and regulations imposed by SCAQMD as well as the California AAQS adopted by CARB and federal AAQS. Ambient Air Quality Standards The Clean An Act (CAA) was passed in 1963 by the US Congress and has been amended several times. The 1970 Clean Air Act amendments strengthened previous legislation and laid the foundation for the regulatory scheme of the 1970s and 1980s. In 1977, Congress again added several provisions, including nonattainment requirements for areas not meeting National AAQS and the Prevention of Significant Deterioration program. The 1990 amendments represent the latest in a series of federal efforts to regulate the protection of au quality in the United States. The CAA allows states to adopt more stringent standards or to include other pollution species. The California Clean Air Act (CCAA), signed into law in 1988, requires all areas of the state to achieve and maintain the California AAQS by the earliest practical date. The California AAQS tend to be more restrictive than the National AAQS, based on even greater health and welfare concerns. These National AAQS and California AAQS are the levels of air quality considered to provide a margin of safety in the protection of the public health and welfare. They are designed to protect "sensitive receptors" most susceptible to further respiratory distress, such as asthmatics, the elderly, very young children, people already weakened by other disease or illness, and persons engaged in strenuous work or exercise. Healthy Page 5.26 PlaceWorkr