THE ADMINISTRATOR OF THE ENVIRONMENTAL PROTECTION AGENCY

The Honorabl e Lynn Valbuena Cha irwoman of San Manuel Band of Serrano Mission Indians 26569 Community Center Drive Hi ghland, Cal iforn ia 92346 Dear Chairwoman Val buena: WASHI N GTON, D.C. 20 460 

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I would like to summa rize the U.S. Environmental Protection Agency's recent action to address fine

particle pollution on your reservation. As required by the Clean Air Act, the EPA has determined which areas are meeting the national ambient-ai r-quality standards for fine-particle pollution and which areas must take steps to reduce emissions that contribute to vio lations of the standard. The EPA on December 14 , 2012, strengthened the annual, health-based fine-particle standard from 15.0 micrograms per cub ic meter (J..lg/m3) to 12.0 J..lg/m 3

. Thousands of scientific studies have link ed exposure to these tiny particles

- approximately 1130th the size of a human hair- with serious health problems including premature death in people with heart and lung disease, nonfatal heart attacks and incr eased hospi tal admissions and doctor and emergency-room visits for respiratory and cardiovascular disease. I appreciate the information you and your staff have shared with the EPA throughout this process to assess fine-particle-pollution levels in communities across yo ur reservation and the impact of emission sources that could be contributing to unhealthy air. After reviewing the most rec ent certified fineparticle air-quality data for the s tate of California and evaluating fac tors to assess contribution to nearby levels of fine particle pollution , I have determined that some areas in California do not meet the 2012 annual fine particle standard or they contribute to a nearby violation of the standard. The EPA is designating those areas " no nattainment. " Some of these areas also include areas of Indian country , including the reservation of the San Manuel Band of Serrano Mission Indians. Nonattainment areas will be required to take action to reduce fine-particle pollution and meet the standard no later than 2021. As required by the Clea n Air Act, those actions may include stricter controls on indu strial facilities and additional planning requirem ents for transportation-related sources. Whil e tribes are not required to take actions, the EPA will work with tribes to develop plans as necessary or appropriate to ensure tribal areas meet the standard no later than 2021. Because air-quality monitoring for 2014 is nearly complete, the EPA, at a tribe's request, will evaluate the status of an area based on its annual fine-particle-monitoring data for 2012- 14. If you would like the EPA to re-evaluate any areas within your reservation, please subm it complete, quality-assured and certified air-quality data for 2014 to the EPA by February 27,2015. I recognize that the EPA shares responsibility with the states and tribes for managing particle-po ll ution levels
. Efforts by states and tribes to attain the 19 97 and 2006 fine-particle-pollution standards are

This paper is printed wi t h vegetable-oil-based inks and is 100-percent post con s umer recycled m a teri a l
. chlorine-free-processed and recyclable.already w o rkin g to reduce unhealthy l eve l s of fine-particle p ollut i on. In addition , curre n t and upcoming federal sta nd ards and safeg uar ds, including pollution-reduction rule s for power plants, vehicles and fuels will ensure s t ea d y reductions of fi n e-p article p ollut ion and will protect pub li c h ea l th in communities

ac r oss the nation. T ogethe r we have made considerab l e progress in reducing fine-particle pollution. Nationwide monitored levels of fin e-particle polluti on have fallen 34 percent s ince 2000 w h e n w e first began s uch monitoring for particl es of thi s s i ze . I am confident this pro gress will continu e as we work t owa rd our shared goal of clean air.

For additional information about t h ese designations , please v i sit www.e pa.g ov / pmdesig n atio n s. S incer ely,