UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                                   WASHINGTON D.C. 20460
                                                               OFFICE OF THE ADMINISTRATOR
                                                                 SCIENCE ADVISORY BOARD

                                     May 12, 2006

Honorable Stephen L. Johnson
Administrator
U.S. Environmental Protection Agency
1200 Pennsylvania Avenue, NW
Washington, DC 20460

       Subject: EPA National Ambient Air Quality Standards Process Review

Dear Administrator Johnson:

       The Clean Air Scientific Advisory Committee (CASAC) has been asked to comment on
the Agency's Re view of the Process for Setting National Ambient Air Quality Standards
(NAAQS) at a public meeting scheduled for June 29, 2006. We wanted to provide some
preliminary thoughts on the proposed process to facilitate our discussion  with the Agency at the
public meeting.

       We are in full agreement that now is the time to think "outside the box" and develop a
significantly-enhanced and streamlined NAAQS review process.  However, in the proposed
process the basic elements of reviewing a given NAAQS remain essentially unchanged. Further,
the "doubling-up"  of the scientific subject matter to be covered at certain CASAC meetings (e.g.,
reviews of the draft Science Assessment and Risk Assessment documents at the same meeting
and, at a subsequent meeting, the Risk Assessment and Policy Assessment documents) may even
increase the number of CASAC meetings. Particularly if these "joint"  reviews are not able to be
orchestrated precisely to plan.  Therefore, it was not apparent to us how the suggested alterations
would make the NAAQS process more efficient or streamlined. On the contrary, EPA's
proposed process appears to be no less time-consuming and likely more resource-intensive than
the current process. Indeed, rather than  helping the Agency more-easily achieve its NAAQS
reviews for the six criteria air pollutants within the statutorily-mandated five-year period (i.e.,
per the Clean Air Act Amendments of 1977 codified at 42 U.S.C. ง Sec. 7409), the proposed
process would seemingly ensure that court-ordered completion dates — the result of external
litigation — would continue to be the principal "driver" for key milestones in these NAAQS
reviews.

       CASAC understands the goal of the NAAQS review process to answer a critical
scientific question, "What evidence has  been developed since the last review to indicate if the
current primary and/or secondary NAAQS need to be revised or if an alternative level or form of
these standards is needed to protect public health and/or public welfare? " We would like to
offer several preliminary thought that we think would help answer this question.

-------
1.  Eliminate the development of a comprehensive Air Quality Criteria Document (AQCD).
   In other words, produce an even more streamlined version of the Science Assessment
   document than is proposed in the NAAQS Workgroup's report. The current AQCD
   represents a compendium of knowledge on the pollutant and its adverse public-health and
   public-welfare effects that consumes much of the review-cycle time and does not focus
   on either the critical question stated above or on the policy-relevant issues to be
   addressed. Moreover, an extensive document of this type is unnecessary. The vast
   majority of the reported studies are not relevant to the setting of a standard, either
   because they have not been published since the previous NAAQS were set or because
   they were conducted at concentration levels so high as to be irrelevant to the
   consideration of a public-health- or public-welfare-based environmental  standard.

2.  Have the Agency's National Center for Environmental Assessment (NCEA) and the
   Office of Air Quality Planning and Standards (OAQPS) jointly convene  a science
   workshop as the first step in the five-year review of each NAAQS. We envision this
   workshop to be an open forum convened by the Agency in which an invited group of
   expert scientists meet to discuss: recent findings regarding adverse low-level effects of
   the pollutant on both public health and public welfare; trends in atmospheric chemistry
   and pollutant distributions; sources of the pollutant or its chemical precursors; risk
   assessment approaches — and, importantly, provide their input to the Agency for the
   development of the likely policy-relevant issues and questions for the criteria air pollutant
   undergoing NAAQS review. EPA staff, CASAC members and the public would be
   present for this workshop, which would allow adequate time for detailed discussions on
   major issues focused on the critical question stated above. This would dovetail with
   EPA's ideas of both "streamlining the process" and linking the earlier and more clear
   identification of the key, policy-relevant issues to the assessment of the adequacy or
   inadequacy of the present primary and secondary NAAQS for criteria air pollutants.

3.  Based on this workshop, and in place of the AQCD, develop a Science Assessment
   document that is essentially equivalent to the integrative synthesis chapter of the AQCD
   and also includes what  is now in the Staff Paper or, as proposed, the Policy Assessment
   document. This Science Assessment would represent Agency staffs recommendation on
   the quality of current science relative to the question of adverse health and environmental
   effects at the existing air quality standard.  The document should then defend that staff
   interpretation of the scientific literature through its summary of studies that directly
   address the critical, policy-relevant questions. As-needed, literature summaries should be
   placed in an appendix, with only those articles deemed to be relevant to the question of
   the current level, form,  averaging time, and indicator for each regulated air pollutant
   included in the primary document.

4.  The above-suggested change would naturally lead to — and require NCEA and OAQPS
   to work together on the development of— a combined Science and Policy Assessment
   document, to be supplemented by the Risk/Exposure Assessment document prepared by
   OAQPS.  This combined  Science and Policy Assessment document would replace the
   former two documents  (i.e., the AQCD and the Staff Paper) and would serve to focus the
   CASAC's and the public's review on the important initial proposals for standard-setting
   — and, notably, result  in a significantly-compressed timeline.  Senior-level Agency

-------
       managers could also of course provide their input at various stages in the development of
       this combined document, as desired.

   5.  As an aspect of the Agency's "continuous compilation/characterization of new studies,"
       develop and maintain an electronic database that contains all publications on the criteria
       air pollutant undergoing evaluation. With EPA having such an electronic database (and,
       of course, providing the recourses necessary to keep it current), the CAS AC or the public
       could, at any point along the timeline for the development and review of the combined
       Science and Policy Assessment document, identify articles and reports they believe EPA
       might have missed that are critical to the "bottom line" questions being addressed.

   6.  Finally, the Assistant Administrators' memo to the Deputy Administrator contemplated
       the option of releasing the Policy Assessment document as an Advanced Notice of
       Proposed Rulemaking (ANPR), which would then undergo CASAC (and public) review.
       The EPA NAAQS Process Review Workgroup's report also noted the potential for
       additional CASAC advice during the rulemaking phase of the NAAQS review. The
       relative merits of these two choices are not completely clear to us.  The only reason that
       CASAC would want or need to comment on an ANPR — or, for that matter, on a
       proposed rule — is if it did not agree with the EPA's proposal, i.e., CASAC's scientific
       recommendations were not adopted by the Agency. As witnessed by our recent response
       to EPA concerning its proposed rule for paniculate matter, the CASAC feels comfortable
       with its suite of available options to provide additional advice to the Agency.

       We hope that these initial thoughts are helpful, and that they will result in more fruitful
discussions with EPA at our June meeting.  The members of CASAC consider this NAAQS
process review to be extremely important, and we look forward very much to continuing to work
with you on this matter.

                                               Sincerely,
                                              Dr. Rogene Henderson, Chair
                                              Clean Air Scientific Advisory Committee
cc:   Marcus Peacock, Deputy Administrator
     Charles Ingebretson, Chief of Staff
     George Gray, Assistant Administrator Office of Research and Development
     William Wehrum, Acting Assistant Administrator, Office of Air and Radiation
     Ellis Cowling, CASAC
     James Crapo, CASAC
     Frederick J. Miller, CASAC
     Richard L. Poirot, CASAC
     Frank Speizer, CASAC
     Barbara Zielinska, CASAC

-------