THE ADMINISTRATOR OF THE ENVIRONMENTAL PROTECTION AGENCY

The Honorable Kyle Self Chairperson of Greenville Rancheria P.O. Box 279 Greenville, California 95947 Dear Chairperson Self: WASHINGTON , D .C . 20460



## ,DEC 1 8

**2~14**

I would like to summarize the U.S. Environmental Protection Agency's recent action to address fineparticle pollution on your reservation. As required by the Clean Air Act, the EPA has determined which areas are meeting the national ambient-air-quality standards for fme-particle pollution and which areas must take steps to reduce emissions that contribute to violations ofthe standard. The EPA on December 14,2012, strengthened the annual, health-based fine-particle standard from 15.0 micrograms per cubic meter

**(~-tg/m**
**)** to 12.0 1-1g/m3
. Thousands of scientific studies have linked exposure to these tiny particles - approximately 1/30th the size of a human hair - with serious health problems including premature death in people with heart and lung disease, nonfatal heart attacks and increased hospital 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-po llution levels in communities across your reservation and the impact ofemission sources that could be contributing to unhealthy air. After cons idering your recommendations, reviewing the most recent certified fine-particle air-quality data for your reservation and eva luating factors to assess contr ibution to nearby levels of fine-particle po llution, I have determined that no area within the Greenville Rancheria reservation violates the 2012 standa rd or contributes to a nearby violation ofthe standard. As a result, the EPA is designating all of the Greenville Rancheria reservation " unclassifiable/attainment." Because air-quality monitoring for 2014 is nearly complete, the EPA, at a tribe ' s request, will evaluate the status ofan 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 submit complete , quality-assured and certifi ed air-quality data for 2014 to the EPA by February 27,20 15. I recognize that the EPA shares respo nsibility with the states and tribes for managing particle-pollution levels. Efforts by states and tribes to attain the 1997 and 2006 fine-particle-pollution standards are already working to reduce unhealthy levels of fine-particle pollution. In addition , current and upcoming federal standards and safeguards, including pollution-reduction rules for power plants, vehicles and fuels will ensure steady reductions of fine-particle pollution and will protect public health in communities across the nation.

This paper is printed with vegetable-oil-based inks and is tOO - percent postconsumer recycled material . chlorine-free-processed and recyclableTogether we have made considerable progress in reducing fine-particle pollution. Nationwide monitored levels of fine-particle pollution have fallen 34 percent since 2000 when we first began such mon i toring for particles of this s i ze. I am confident this progress will continue as we work toward our shared goal of clean air.

For additional i nformation about these designat i ons, please visit www.epa.gov / pmdesignations. **~** - G i na McCarthy