UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION IX 75 Hawthorne Street San Francisco, CA 94105·3901

OFFICE OF THE REGIONAL ADMINISTRATOR 

## JUN 1 4 2011

The Honorable Brian Sandoval GovernorofNevada 101 North Carson Street Carson City, Nevada 89701 Dear Governor Sandoval: Thank you for your State'srecommendation regarding the air quality designation for the revised National Ambient Air Quality Standards for lead throughoutNevada. This letter is to notify you ofthe U.S. Environmental Protection Agency's (EPA's) preliminary decision to designate Nevada as unclassifiable/attainment and to infonn you ofour approach for completingthe designations for the revised lead standards. Reducing levels oflead pollution is an importantpart ofthe EPA's commitment to a clean, healthy environment. Lead exposure can cause a range ofadverse health effects, most notably in children. Exposures to low levels oflead early in life have been linked to effects on IQ, learning, memory, and behavior. On October 15,2008, the EPA substantially strengthened the health-based or "primary"National Ambient Air Quality Standard for lead by lowering it from 1.5 micrograms per cubic meter ().lg/m3) - a level set in 1978

- to a level of0.15 ).lg/m3

. This stronger standard provides increased protection against adverse health effects associated with exposure to lead in at-risk groups, including children. To provide increased protection against lead-related environmental and otherwelfare effects, the EPA revised the secondaryNational AmbientAir Quality Standard to beidentical in all respects to therevised primary standard. The EPA also detetmined that the pre-existing ambient lead monitoring network was inadequate for detennining whethermany areas are meeting the revised lead standards and established new criteriafor sitingambient lead monitors and new data collection requirements. Monitors meeting the new network sitingrequirements were to begin operationJanuary 1,2010. Withintwo years ofpromulgating new orrevised National Ambient Air Quality Standards, the Clean AirAct requires the EPA to complete the initial process ofidentifyingor designating areas thatmeet or do not meet an air quality standard. Ifthe Administrator has insufficient infonnation to make these designations, the EPA has the authority to extend the designation process by up to one year. In light of the new monitoring network, the EPA is completingthe lead designations in two rounds. In the first round, published on November 16, 2010, the EPA designated as "nonattainment" 16 areas as violating the 2008 Lead National Ambient Air Quality Standards based on data from the pre-201O monitoring network. For all other areas, the EPA extended the deadline for designations by up to one year so that

Printed on Recycled Paperdata from the newly deployed monitors can be considered in makingappropriate designation decisions. States were given an opportunity to update their recommendation letters for those remainingareas for ourconsideration in the second round ofdesignations by December 15, 

### 2010. The EPA intends to complete the second round oflead designations by no later than October 

### 14, 2011. Consistent with the Clean Air Act, and aftercarefully considering Nevada's October 

### 9, 2009 recommendation letter and all the associated technical information for the 

### 2008 Lead National Ambient Air Quality Standards, includingthe most recent air qualitydata from 

### 2008-2010, the EPA is proposing to designate Nevadaas unclassifiable/attainment. TheEPAuses this designation for initial designations to identify areas that have data indicating attainment, or where there is no evidence ofa violation. Ifyour state has additional information that the EPA should consider with respect to ourproposed modification to your designation recommendation, please submit it to us by August 

### 15, 2011. The EPA's preliminary designation decisions and supporting documentation will be made available to the general public for review. We will be acceptingcomments through August 

### 15, 2011. We will review any information wereceive from the StateofNevada and the general publicbythis date, and we plan to promulgatethe second round offinal designations by October 

### 14, 2011. We look forward to a continued dialogue with you and your staffas we work together to implement the 

### 2008 Lead National AmbientAir Quality Standards. Should you have any questions, please do not hesitate to call me, orhave your staffcontact Air Division Director Deborah Jordan at 

### 415-947-8715.

cc: Colleen Cripps Administrator, NDEP Rob Bamford Bureau Chief, Bureau ofAir Quality Planning, NDEP