UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

WASHINGTON, D.C. 20460 

AUG 0 8 2014 

MEMORANDUM 

SUBJECT: Particle Pollution Quality Assurance 

FROM: Janet G. McCab~....tt-G::· .:/~L'­

Acting Assistant Administrator 

TO: Arthur A. Elkins Jr., Inspector General 

Office of Inspector General 

OFFICE OF 

AIR AND RADIATION 

As part of our responsibilities under the Clean Air Act, the U.S. Environmental Protection Agency 

(EPA) conducts Technical System Audits (TSA) of state and local ambient air monitoring programs. 

These audits review and evaluate all aspects of the monitoring program from field operations to 

laboratory operations and include a review of the quality assurance/quality control (QA/QC) criteria in 

place at various steps in these monitoring programs. 

Recently, our audits have identified concerns with four monitoring laboratories associated with three 

state and local programs located in Regions 4 and 5. These laboratories did not meet certain critical 

QA/QC criteria related to the weighing of the fine particle (PM2.s) filters, and as a result, data from these 

filters must be invalidated. The loss of these data related to the weighing of the fine particle (PM2.s) 

filters is of concern. I note, however, that we have redundancies in our air monitoring program, 

including data from non-filter based PM2.s monitors, which were unaffected and continued to provide 

reliable air quality information to the public in these areas (e.g., airnow.gov). In addition and 

importantly, EPA's audits of other monitoring programs did not identify issues of concern extending 

beyond these particular laboratories. In fact, in response to the detection of these discrepancies, OAQPS, 

in conjunction with the EPA Regional Offices, conducted an even more detailed review of the status of 

all laboratories involved with PM2.s analyses across the country and found, with the exception of the 

four laboratories above, reliable results based on TSAs conducted over the past 3 years. 

While we have worked with the affected states to identify a path forward to resolve the concerns for the 

areas affected by this data quality issue and taken immediate steps to address the problems identified and 

remain confident that these data quality issues are limited to these laboratories, we wanted to inform you 

of this situation given your office's critical programmatic audit and oversight role at the EPA. I am also 

aware that your office is initiating a review of the Region 6 PM data program so our recent audit 

findings may be timely and important for you to consider. 

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

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While I am happy to provide you more detailed information, I wanted to advise you that the Office of 

Air Quality Planning and Standards (OAQPS) has been working closely with the Regions and affected 

states to ensure that actions are taken in the national Air Quality System database to flag or invalidate 

data, as appropriate. They have also been working diligently to ensure that appropriate corrective actions 

are taken, which to date have included the closure of the related state and local laboratories in Region 4, 

and the review of operational procedures and implementation of recommendations in the local 

laboratory in Region 5. In addition, an independent audit of all of the labs in Region 5 that conduct PM 

analyses will be completed within the next 60 days, and a review of state grants language to emphasize 

the states' responsibility for overseeing the monitoring program is underway. OAQPS is also in the 

process of developing training and outreach materials to ensure national awareness of these problems 

across all monitoring agencies. Through these actions, we believe the problems can be corrected and 

avoided in the future. 

Again, based upon the data in TSAs conducted across the country, the EPA believes the issues described 

above are limited to the areas identified above, and the agency is actively working to address these 

issues. If you have any questions regarding our audit program, please feel free to contact me directly or 

your staff may contact Chet Wayland (wayland.richard@epa.gov) or Lew Weinstock 

(weinstock.lewis@epa.gov) of my staff for further information. We would be happy to arrange a 

meeting with your staff to discuss these issues.