UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION IX 

75 Hawthorne Street
 

San Francisco, CA 94105·3901
 

OFFICE OF THE 

REGIONAL ADMINISTRATOR 

JUN 2 9 2011 

The Honorable Marjorie Mejia 

Chairperson 

Lytton Rancheria of California 

1300 N. Dutton Avenue, Suite A 

Santa Rosa, California 95401 

Dear Chairperson Mejia: 

Thank you for your recommendation on the air quality designation for the revised primary National 

Ambient Air Quality Standard (NAAQS) for nitrogen dioxide (N02) on behalf of the Lytton Rancheria. 

This letter is to notify you of the U.S. Environmental Protection Agency's (EPA's) preliminary decision 

to designate the Lytton Rancheria trust lands in San Pablo, California as unclassifiable/attainment and to 

inform you of our approach for completing the designations for the revised N02 NAAQS. 

On January 22,2010, the EPA strengthened the health-based NAAQS for N02 by setting a new I-hour 

N02 standard at the level of 100 parts per billion (ppb). The EPA also retained with no change, the 

annual average N02 standard of 53 ppb. This suite of standards will protect public health by limiting 

people's exposures to short-term peak concentrations of N02 and by limiting community-wide N02 

concentrations to levels below those that have been linked to respiratory-related emergency department 

visits and hospital admissions in the United States. 

In our November 2010 letter to you requesting designation recommendations, the EPA stated that it 

expected to designate most areas of the country as "unclassifiable," indicating that there are insufficient 

data to determine whether or not an area is attaining the revised N02 NAAQS. This approach took into 

account that the new monitoring network requirements established with the revised N02 NAAQS will 

not be in place until January 2013 and that air quality data from these new monitors would not be 

available to inform these initial designations. 

The EPA has reviewed your recommendations and intends to designate the Lytton Rancheria trust lands 

as "unclassifiable/attainment" rather than "unclassifiable." While the EPA acknowledges that the 

existing N02 monitoring network does not provide adequate evidence to determine whether or not the 

new NAAQS is met in all areas, there currently is no evidence of violations anywhere. The 

"unclassifiable/attainment" designation better reflects the current air quality conditions. The EPA 

intends to redesignate areas, as appropriate, after sufficient air quality data from the new monitoring 

network are available. 

If you have additional information that you want the EPA to consider with respect to the designation of 

the Lytton Rancheria trust lands, please submit it to us by August 29,2011. We are also making the 

EPA's preliminary designation decisions and supporting documentation available to the general public 

for review. We are accepting public comments on our preliminary decisions for 30 days after a notice 

Printed on Ruyded Paper 
announcing the public comment period is published in the Federal Register. We will review any 

information we receive from you and the general public by this date, and we plan to promulgate the final 

designations by October 31, 2011. 

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

2010 N02 NAAQS. Should you have any questions, please do not hesitate to call me, or have your staff 

contact Colleen McKaughan of my staff at 520-498-0118. 

Sincerely, 

Cc: Mr. Brent Gudzus, Environmental Director