AMATS Air Quality Update April 2012

1. AMATS Air Quality Update April 2012 Municipality of Anchorage Department of Health and Human Services

2. Status Report • Carbon monoxide (CO) • Particulate matter (PM10 & PM2.5) • Ozone • Airborne lead • Air toxics (benzene) • Sulfur dioxide, nitrogen dioxide

3. Colorless odorless gas produced by incomplete combustion 79% of emissions from motor vehicles Highest concentrations occur on cold mid-winter days with strong temperature inversions Residential areas tend to have highest concentrations CO

4. Anchorage CO Trend

5. Comparison with CO Concentrations in Selected Western Cities in U.S. (2010)

6. PM2.5 (2.5 µm) PM10 (10µm) PM10 and PM2.5 Width of human hair • Linked with asthma and other respiratory health problems • Death rates in hospitals increase when PM2.5 concentrations are high • Anchorage studies show that there are more doctor visits for asthma when PM10 levels increase

7. Occasional violations of the NAAQS in spring at Tudor Road site due to road dust. Magnesium chloride is being used to suppress dust along 40 miles of high volume roadways in Anchorage and Eagle River. Eagle River regularly violated NAAQS in late-1980’s before roads were paved Strong winds transported dust from glacial river valleys in Mat Su causing exceedances of NAAQS in 2003, 2007, 2009, and 2010. PM10 September 24, 2010MODIS satellite image

8. PM2.5 • Generally low concentrations in Anchorage (ranked 6th cleanest city for year-round PM2.5 pollution by ALA) • C14 analysis of Anchorage samples suggests that most PM2.5 is from wood smoke • Assembly passed outdoor wood boiler ordinance restricting installations to those meeting EPA-certified Phase 2 standards. NESCAUM 2006

9. No obvious upward or downward trend in PM10 or PM2.5 during past 10 years

10. Secondary pollutant produced by a chemical reaction between oxides of nitrogen and volatile organic compounds in the presence of sunlight. Ozone in stratosphere protects us from UV Causes respiratory irritation, coughing, pain Highest concentrations seen downwind of major urban centers in summer O3 levels in Anchorage and Eagle River were among the lowest 1% of sites in U.S. Ozone (O3) Ozone is the main ingredient in “smog.”

11. Airborne Lead • EPA study of 15 mid-sized airports serving piston aircraft • Unlike gasoline, aviation fuel still contains lead additive • One-year study at Merrill Field will conclude Oct 2012 • Will not be used to assess attainment with the new ambient lead standard • Preliminary data suggest that concentrations at Merrill Field are below standard

12. Phase 2 (planned) Aug 2012 – Aug 2013 Gasoline benzene <1.3% How much will ambient benzene concentrations be reduced? Air toxics (benzene) DHHS is monitoring ambient benzene to assess impact of new EPA limits on the amount of benzene in gasoline Phase 1 (completed) • Oct 2008 – Oct 2009 • Gasoline benzene ≈ 5% • Found average ambient benzene levels at Garden site in Airport Heights to be in 98th percentile of U.S. sites

13. Garden site(Anchorage) Annual Average [benzene] = 1.1 ppb Galena Park, TX(near Houston) Annual Average [benzene] = 1.1 ppb

14. Summary • CO has fallen dramatically and is expected to continue to decline, but more slowly than the past. • PM10 is a problem during spring break up. Magnesium chloride is used to control dust on major roads. Unpaved road problem in Eagle River has been resolved. • PM2.5 is fairly low but could pose a problem if wood burning increases. • Ozone levels are among lowest in the U.S. • Benzene concentrations were among highest in U.S. in 2008-09. The impact of lowering the gasoline benzene content from 5% to 1.3% or lower will be evaluated this coming year.