UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION 6

1445 ROSS AVENUE, SUITE 1200

DALLAS TX 75202-2733

JUN 1 4 2011

The Honorable Mary Fallin

Governor of Oklahoma

2300 North Lincoln Boulevard, Suite 212

Oklahoma City, Oklahoma 73105

Dear Governor Fallin:

Thank you for your recommendations on air quality designations for the revised National

Ambient Air Quality Standards for lead throughout Oklahoma. This letter is to notifY you ofthe

U.S. Environmental Protection Agency's (EPA) preliminary decision to designate all of

Oklahoma 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

ofthe 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 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 by lowerin¥ it from 1.5 micrograms per cubic meter (fig/m3

) - a

level set in 1978 - to a level of 0.15 fig/m . 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

arnbient 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. Ifthe 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 ofthe 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-201O monitoring network. For all other areas, the EPA extended the

deadline for designations by up to one year so that 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.

Internet Address (URL) • http://www.epa.gov/region6

Recycled/Recyclable _ Printed with Vegetable Oil Based Inks on 100% Recycled Paper, Process Chlorine Free
Consistent with the Clean Air Act, and after carefully considering Oklahoma's September 29,

2009, recommendation letter and all the associated technical information for the 2008 Lead

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

2010, the EPA is proposing to designate Oklahoma as unclassifiable/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.

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 information we receive from the State of Oklahoma 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 hesitate to call me, or have your staff contact Mr. Guy Donaldson of my

staff at (214) 665-7242.

Al Armen ariz

Regional Adrninistrat r

cc: Mr. Gary Sherrer

Secretary ofthe Environment

Mr. Steven Thompson, Executive Director

Oklahoma Department of Environmental Quality