UNITED STATES ENVIRONMENTAL PROTECTION AGENCY REGION 8 1595WYNKOOP STREET DENVER, CO 80202-1129 Phone 800-227-8917 http://www.epa.gov/region08

8P-AR 

# rJUN 14 2011

Christopher E. Urbina, MD, MPH Executive Director and ChiefMedical Officer Colorado Department ofPublic Health and Environment 4300 Cherry Creek Dr. S. Denver, Colorado 80246-1530

Dear Dr. Urbina:

Thankyou for your recommendations on air quality designations for the revised National Ambient Air Quality Standards for lead throughout Colorado. This letter is to notify you ofthe U.S. Environmental Protection Agency's (EPA's) preliminary decision to designate all of Colorado as attainmentlunclassifiable, and to inform you ofour approach for completing the designations for the revised lead standards. Reducing levels oflead pollution is an importantpart ofthe EPA's commitment to a clean, healthy environment. Lead exposure cancause a range of adverse health effects, most notably inchildren. 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 strengthenedthe health-based or "primary" National AmbientAir Quality Standard by**lowerin~** it from 1.5 micrograms per cubic meter (flg/m3)

- a level set in 1978

- to a level of0.15 flg/m

.This stronger standardprovides 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 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 standard and established newcriteriafor siting ambient lead monitors and newdata collectionrequirements. Monitors meeting the newnetwork siting requirements
were to begin operationJanuary 1,2010.

Within two years ofpromulgating neworrevised National AmbientAir Quality Standards, the Clean Air Act requires the EPA to complete the initial process ofidentifying ordesignating areas that meet or do not meet an air quality standard. Ifthe Administratorhas insufficient information to make these designations, the EPA has the authority to extend the designation process by up to
one year. In light ofthe newmonitoring network, the EPA is completingthe lead designations in two rounds. In the first round, published onNovember 16, 2010, the EPA designated as "nonattainment" 16 areas as violating the 2008 Lead National Ambient Air Quality Standardsbased on data from the pre-2010 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 theirrecommendation letters for those remaining areas for our consideration in the second round ofdesignations by December 15, 2010. The EPA intends to completethe second round of lead designations by no laterthan October 14, 2011.

Consistent with the CleanAirAct, and after carefully considering Colorado's October 15,2009, 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 Colorado 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 ofa violation.

Ifyour state has additional informationthat 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 information we receive from the state ofColorado and the general public by this date, and we planto promulgate the second round offinal designations by October 14, 2011.

We look forward to a continued dialogue with you and your staffas we work togetherto implement the 2008 Lead National Ambient Air Quality Standards. Should you have any questions, please do not hesitate to call me, orhave your staffcontact Carl Daly ofmy staffat (303) 312-6416.

Sincerely, 

# \..

..

# 2--,~

# {~~**~egional** Administrator

cc: Martha E. Rudolph, Director Environmental Programs

Paul Tourangeau, Director AirPollution Control Division

Gina McCarthy, Assistant Administrator for Air and Radiation Steven D. Page, Director, Office ofAir Quality Planning and Standards