January 10, 1990  
  
  
  
  
  
  
  
MEMORANDUM  
  
SUBJECT:  Review of The Utah County PM-10 Draft SIP  
  
FROM:     Joseph A. Tikvart, Chief  
          Source Receptor Analysis Branch, TSD (MD-14)  
  
TO:       Lee Hanley, Utah County PM-10 SIP Coordinator  
          Region VIII (8AT-AP)  
  
  
    As per your request to Dean Wilson, the Model Clearinghouse has
reviewed  the source apportionment section in the Utah County PM-10 draft
SIP.  The State of Utah has used two independent techniques which include
the Microinventory and Chemical Mass Balance (CMB) methods to attribute
source contributions to the majority of the monitored PM-10 violations in
the Utah County.  Use of these methods in the draft Utah SIP obviously
reflects a major effort by the State.  Our only comment is in regard to the
CMB analyses.  We  note that values reported in the summary sheets for
calculated PM-10 and total percent mass differ from those reported in the
CMB output tables (i.e., CMBOUT) for Lindon, North Provo and West Orem
sites.  While both sets of numbers appear reasonable, a single consistent
set should be selected.  
  
    If you have any questions, please contact Quang Nguyen (FTS 629-0832)
or  Dean Wilson (FTS 629-5683) of my staff.  
  
cc:  E. Meyer  
     T. Pace  
     D. Wells  
     D. Wilson