UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
 

REGION IX
 

75 Hawthorne Street
 

San Francisco, CA 94105·3901
 

OFFICE OF THE 

REGIONAL ADMINISTRATOR 

JlIN 1 4 2011 

The Honorable Janice Brewer 

Governor of Arizona 

1700 West Washington 

Phoenix, Arizona 85007 

Dear Governor Brewer: 

Thank you for your State's recommendations regarding the air quality designation for the revised 

National Ambient Air Quality Standards for lead throughout Arizona. This letter is to notify you of the 

U.S. Environmental Protection Agency's (EPA's) preliminary decision to designate Arizona as 

unclassifiable/attainment and to inform you of our approach for completing the designations for the 

revised lead standards. 

Reducing levels of lead pollution is an important part of the EPA's commitment to a clean, healthy 

environment. Lead exposure can cause a range of adverse health effects, most notably in children. 

Exposures to low levels of lead 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" Lead National 

Ambient Air Quality Standard for lead by lowering it from 1.5 micrograms per cubic meter (flg/m3

) - a 

level set in 1978 - to a level of 0.15 flg/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 other welfare effects, the EPA revised the 

secondary National Ambient Air Quality Standard to be identical in all respects to the revised primary 

standard. The EPA also determined that the pre-existing ambient lead monitoring network was 

inadequate for determining whether many areas are meeting the revised lead standards and established 

new criteria for siting ambient lead monitors and new data collection requirements. Monitors meeting 

the new network siting requirements were to begin operation January 1,2010. 

Within two years of promulgating new or revised National Ambient Air Quality Standards, the Clean 

Air Act requires the EPA to complete the initial process of identifying or designating areas that meet or 

do not meet an air quality standard. If the Administrator has insufficient information 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 completing the 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-20lO monitoring 

network. For all other areas, the EPA extended the deadline for designations by up to one year so that 

Prinl~d on Recycled Paper 
data from the newly deployed monitors can be considered in making appropriate designation decisions. 

States were given an opportunity to update their recommendation letters for those remaining areas for 

our consideration in the second round of designations by December 15, 2010. The EPA intends to 

complete the second round of lead designations by no later than October 14, 2011. 

Consistent with the Clean Air Act, and after carefully considering Arizona's recommendation letters of 

December 15,2009 and December 15,2010, and all the associated technical infonnation for the 2008 

Lead National Ambient Air Quality Standards, including the most recent air quality data from 2008­

20 10, the EPA is proposing to designate Arizona as unclassifiab1e/attainment. The EPA uses this 

designation for initial designations to identify areas that have data indicating attainment, or where there 

is no evidence of a violation. 

If your state has additional infonnation that the EPA should consider with respect to our proposed 

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 accepting comments through August 15,2011. We will review 

any infonnation we receive from the State of Arizona and the general public by this date, and we plan to 

promulgate the second round of final designations by October 14, 2011. 

We look forward to a continued dialogue with you and your staff as we work together to implement the 

2008 Lead National Ambient Air Quality Standards. Should you have any questions, please do not 

hesi tate to call me, or have your staff contact Air Division Director Deborah Jordan at 415-947-8715. 

cc:	 Henry Darwin, 

Director, ADEQ 

Eric Massey 

Director, Air Quality Division, ADEQ 

Nancy Wrona 

Policy Advisor, ADEQ