SCAQMD RULE 1306 EMISSION CALCULATIONS                         
LAST REVISED 05/03/91



(Adopted Oct. 5, 1979)(Amended March 7, 1980)(Amended Sept. 10, 1982)
(Amended Dec. 3, 1982)(Amended July 12, 1985)(Amended August 1, 1986)
(Amended Sept. 5, 1986)(Amended June 28, 1990)(Amended May 3, 1991)

          RULE 1306.EMISSION CALCULATIONS

          (a)  General
               This  Rule  shall  be  used  as  the basis for calculating
               applicability of Regulation XIII as stated in Rule 1301(b)
               and  Rule 1303.  This Rule shall also  be  the  basis  for
               calculating  daily  emission  increases and decreases used
               for  New  Source  Review  Balance and  Emission  Reduction
               Credits.


          (b)  Emission Increases
               Emission increases for new  permit units and the new total
               emissions for modified permit  units  shall be calculated,
               as approved by the Executive Officer, (1) using a calendar
               monthly  average  and  (2) on a pound-per-day  basis  from
               permit conditions which  directly  limit the emissions or,
               when no such conditions are imposed, from:
               (1)  the maximum rated capacity; and
               (2)  the maximum daily hours of operation; and
               (3)  the   physical   characteristics  of   the   material
                    processed.

               For the purpose of calculating  offsets only, the calendar
               monthly average shall be used.


          (c)  Actual Emission Decreases
               Emission decreases from permit units which are modified or
               removed from service shall be the actual emissions reduced
               to the amount which  would  be actual if current BACT were
               applied.  The emission amount shall be calculated from the
               following:
               (1)  The  sum  of  actual emissions,  as  determined  from
                    company  records,   shall  include  annual  emissions
                    declarations pursuant  to  Rule  301,  or  other data
                    approved by the Executive Officer, whichever is less,
                    which  have  occurred  each  year during the two-year
                    period  immediately  preceding  the  date  of  permit
                    application, or other appropriate  period  determined
                    by the Executive Officer to be representative of  the
                    source's  cyclical  operation,  and  consistent  with
                    federal requirements;
               (2)  The sum of BACT adjusted  annual  emissions  shall be
                    divided by the total number of actual operation  days
                    in each of those two years or other approved period;
               (3)  The  calculated emission from above subparagraphs (1)
                    and (2)  shall  be  multiplied  by  the  usage factor
                    appropriate to the use of the subject permit units in
                    each  of  the  two  years  used  for calculation,  as
                    follows:
                         
                         1.0 when operated 180 days or more,
                         0.5 when operated 30 to 179 days, and
                         0.0 when operated less than 30 days.
               
               (4)  Daily emissions shall be determined  for  each  year.
                    The  average  value shall be calculated for those two
                    years or other approved period.
               The BACT adjustment shall not apply to facilities located in
               the non-Air  Quality  Maintenance Area  (AQMA) region of the
               Southeast Desert Air Basin.


          (d)  Emission  Determination  for  the  NSR  Balance  (Not  for
               Determining ERCs)
               This subsection shall be used for determining  the  sum of
               emission  increases and decreases that have occurred at  a
               facility since October 8, 1976.
               (1)  New Equipment Requiring a Permit (No Previous Permit)
                    Emissions are calculated pursuant to Rule 1306(b) and 
                    added to the NSR Balance.
               (2)  Existing Permit Unit  that was subject to Rule 213 or
                    Regulation XIII when its  original permit application
                    was deemed complete.
                    (A)  Modification:
                         Emissions after the modification  are calculated
                         pursuant to Rule 1306(b) and added  to  the  NSR
                         Balance.   All  previous  emissions  in  the NSR
                         Balance  associated  with  the  permit  unit are
                         removed.
                    (B)  Shutdown:
                         All   previous  emissions  in  the  NSR  Balance
                         associated with the permit unit are removed.
               (3)  Existing Permit  Unit,  never  previously  subject to
                    Rule 213 or Regulation XIII
                    (A)  Modification:
                         Emissions  added  to  the  NSR  Balance are  the
                         potential  to emit calculated pursuant  to  Rule
                         1306(b) minus  the  decrease calculated pursuant
                         to Rule 1306(c).
                    (B)  Shutdown:
                         Decreases shall be calculated  pursuant  to Rule
                         1306(c) and subtracted from the NSR Balance.
               (4)  Existing  Permit  Unit that was not initially subject
                    to Regulation XIII  or  Rule  213,  when its original
                    permit   application   was   deemed   complete,   but
                    subsequently subject to Regulation XIII  or  Rule 213
                    because of a modification.
                    (A)  Additional Modification:
                         The  change  in  potential to emit is calculated
                         and added to the NSR Balance.
                    (B)  Shutdown:
                         All  previous  entries   in   the   NSR  Balance
                         associated  with  the  permit  unit are removed.
                         The first calculation of actual  emissions after
                         October 8, 1976, shall be credited.   If  actual
                         emissions  have  not been previously calculated,
                         current actual emissions  as  determined in Rule
                         1306(c) shall be used.

          (e)  Determination of Emission Reduction Credit
               This paragraph shall be used for determining all  Emission
               Reduction Credits.
               (1)  All Modifications:
                    Emission credit shall be based upon the new potential
                    to emit calculated pursuant to Rule 1306(b) minus the
                    decrease calculated pursuant to Rule 1306(c).
               (2)  All Shutdowns:
                    Emission  credit shall be  based  upon  the  decrease
                    calculated pursuant to Rule 1306(c).
               (3)  The ERC shall equal  the  emission  credit at the facility
                    determined pursuant to (e)(1) or (e)(2) minus the NSR
                    Balance at the same facility.  The  NSR  Balance must
                    be zero for an ERC to be granted.


          (f)  Air Pollution Controls
               For the modification of any permit unit installed prior to
               October  8,  1976  resulting  from  the  addition  of  air
               pollution controls installed solely to reduce the issuance
               of  air  contaminants, emissions shall be calculated,  for
               purposes of  Rule  1303  determination  only,  from permit
               conditions which directly limit the emissions or,  when no
               such conditions are imposed, from:
               (1)  the maximum rated capacity; and
               (2)  the maximum proposed daily hours of operation; and
               (3)  the   physical   characteristics   of  the  materials
                    processed.
               This subsection shall not be used to calculate an Emission
               Reduction  Credit  or to change an existing  NSR  Balance.
               Any  reduction credit  obtained  shall  be  determined  by
               subparagraphs (b), (c) and (e).


          (g)  NSR Balance
               (1)  The  NSR  Balance,  which  must  be offset to zero in
                    accordance with Rule 1303(b)(2), will be the sum of:
                    (A)  The facility net emission increase  in effect on
                         September 28, 1990 under the previous Regulation
                         XIII after emissions from each permit  unit have
                         been discounted by 20 percent; and
                    (B)  All  emission  increases  or  decreases  at  the
                         facility,  occurring  after  September 28, 1990,
                         calculated pursuant to Rule 1306; and
                    (C)  All ERC certificates turned in  for  use  at the
                         facility,  divided  by the offset factor in Rule
                         1303(b)(2).
               (2)  All net facility emission  decreases on September 28,
                    1990 will be set to zero and  be  eligible for an ERC
                    in accordance with Rule 1309(a)(1).  All net facility
                    emission increases that were offset  will  be  set to
                    zero.
               (3)  All   increases  or  decreases  associated  with  the
                    equipment  exempted  by  Rule  1304 shall be excluded
                    from the NSR Balance, except for  concurrent Facility
                    Modifications,    portable   equipment,    regulatory
                    compliance, and relocations  of  permit units subject
                    to New Source Review at the prior locations.
               (4)  Essential Public Services eligible  for  the Priority
                    Reserve,  pursuant to Rule 1309.1, shall not  include
                    emission increases  or  decreases  occurring  at  the
                    facility  prior  to  September  28,  1990  in the NSR
                    Balance.  Any net emission decrease shall be eligible
                    for an ERC pursuant to Rule 1309.


          (h)  Mobile Sources
               The   following   mobile   source  emission  increases  or
               decreases  directly associated  with  the  subject  permit
               units shall be accumulated:
               (1)  Emissions from in-plant vehicles; and
               (2)  All  emissions  from  ships  during  the  loading  or
                    unloading of cargo and while at berth where the cargo
                    is loaded or unloaded; and
               (3)  Nonpropulsion  ship  emissions  within Coastal Waters
                    under District jurisdiction.


          (i)  PM10 Emissions
               The  PM10  emissions  from an existing facility  shall  be
               recalculated from the Total  Suspended  Particulate  (TSP)
               emission increases and decreases which have occurred since
               October  8, 1976, using PM10 emission factors, as approved
               by the Executive Officer.