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                     STATES ENVIRONMENTAL PROTECTION AGENCY
                               WASHINGTON D.C, 20460

                                 December 16, 1991
                                                                       OFFICE or
                                                                    THE ADMINISTRATOR
                                                                  SCIENCE ADVISORY BOARD
EPA-SAB-CASAC-CON-92-002

The Honorable William K. ReiEy
Administrator
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C, 20460

             Subject: Science Advisory Board Notification of a Consultation on
             Prioritizing the 189 Hazardous Air Pollutants listed in the 1990
             Clean Air Act Amendments,

Dear Mr, leilly;

       On October 28-29, 1991, a Panel of the Clean Air Scientific Advisory Committee
(CASAC) of the Science  Advisory Board-(SAB) met with staff of the Office of Air and
Radiation and conducted a consultation on EPA*s approach to prioritizing the 189 hazardous
air pollutants listed in the Clean Air Act Amendments of 1990. The SAB has developed the
consultation as a mechanism to advise the Agency on technical issues that should be
considered in the development of regulations, guidelines, or technical guidance before the
Agency has taken a position.  A consultation is conducted under the normal provisions of the
Federal Advisory Committee Act, which includes advance notice of the public meeting in the
Federal Register.  A response to this consultation from the Agency is not solicited.
                                                                                  «*
       We believe that this consultation achieved its goal by raising several important issues
that EPA could  consider in developing its prioritization scheme.  As is our customary
practice, this consultation does not constitute a formal report from the SAB.  However,
individual members of the panel may provide comments, or the Committee may provide
more guidance at a later date in a Commentary or through a formal review.

       We look forward to advising the Agency in the future by consultations as well as
through more formal scientific reviews.
                                      Sincerely
                                      Roger O. McClellan, Chairman
                                      Clean Air Scientific Advisory Committee
                                      Science Advisory Board

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