MOJAQMD RULE 1157 BOILERS AND PROCES HEATERS
LAST REVISED 10/26/94

          (Adopted: October 26, 1994)


                                      Rule 1157
                             Boilers and Process Heaters


          (A)  General

               (1)  Purpose:   The  purpose  of  this  rule is to limit NOx
                    emissions    from   industrial,   institutional,    and
                    commercial  boilers,   steam  generators,  and  process
                    heaters.

               (2)  Applicability:

                    (a)  This rule applies to  new  and  existing  boilers,
                         steam  generators,  and  process  heaters  located
                         within the Federal Ozone Non-attainment Area  with
                         rated  heat  inputs  of greater than or equal to 5
                         million Btu per hour (MMBtu/hr)  which are used in
                         all  industrial,  institutional,  and   commercial
                         operations,   including   permit   units  used  by
                         independent   power   producers  and  cogeneration
                         projects.

                    (b)  This rule does not apply  to  permit  units  whose
                         sole  purpose  is  the  production  of  steam  for
                         electrical  power  generating  equipment  when the
                         permit  unit  is  located  at  a facility directly
                         regulated by a Public Utilities Commission.

               (3)  Applicability of other District Rules:  Compliance with
                    this rule does not exempt a person from  complying with
                    any  other  applicable  State,  federal  or local  law,
                    statute, code, ordinance, rule, or regulation.


          (B)  Definitions

               For  the  purposes  of  this rule, the following definitions
               shall apply:

               (1)  "Annual Heat Input":  the total heat input of fuels, in
                    Btu, burned by a permit  unit  in  a  calendar year, as
                    determined from the higher heating value and cumulative
                    annual usage of each fuel.

               (2)  "Best  Available Retrofit Control Technology"  (BARCT):
                    an emission  limitation  that  is  based on the maximum
                    degree  of  reduction achievable, taking  into  account
                    environmental,  energy,  and  economic  impacts by each
                    class or category of source.

               (3)  "Boiler or Steam Generator":  any combustion  equipment
                    (fired with any fuel) used to produce steam.  Boiler or
                    steam   generator  does  not  include  any  waste  heat
                    recovery  boiler  that is used to recover sensible heat
                    from the exhaust of a combustion turbine.

               (4)  "Cogeneration Facility":  a facility which produces:

                    (a)  electric energy; and

                    (b)  steam or forms  of  useful  energy  (such as heat)
                         which   are  used  for  industrial  or  commercial
                         heating or cooling purposes.

               (5)  "Emissions Control  Plan":   a  document which outlines
                    how   an  existing  facility  will  comply   with   the
                    requirements  of this rule.  The plan shall contain the
                    following:

                    (a)  a list of  all  permit units with their rated heat
                         inputs and estimated annual heat inputs; and

                    (b)  for permit units  subject  to subsection (C)(3)(a)
                         or  (C)(4)(a), for each permit  unit  listed,  the
                         selected   method   of  achieving  the  applicable
                         standard or standards  of  subsection (C)(3)(a) or
                         (C)(4)(a); and

                    (c)  for permit units subject to  subsection  (C)(3)(b)
                         or  (C)(4)(b),  for  each  permit  unit listed,  a
                         selection of one of the four options  specified in
                         subsection   (C)(3)(b)  or  (C)(4)(b)  to  achieve
                         compliance with this rule; and

                    (d)  for permit units  for  which  installation  of NOx
                         reduction  technology  by  May  31,  1995  is  not
                         practicable,   a   demonstration   of   why   such
                         installation  cannot  be achieved by that date, as
                         well as a schedule of clearly  defined  compliance
                         milestones  that  represent  the  most expeditious
                         schedule practicable toward final compliance.

               (6)  "Federal Ozone Non-attainment Area":  that  portion  of
                    San  Bernardino County that lies within the lines which
                    begin at:

                    (a)  the   San  Bernardino/Riverside  County  boundary,
                         running north along the range line common to Range
                         3 East and Range 2 East;
                    (b)  then  west  along  the  township  line  common  to
                         Township 2 North and Township 3 North;

                    (c)  then north  along  the  San Bernardino/Los Angeles
                         County  boundary  and the San  Bernardino  /  Kern
                         County Boundary;

                    (d)  then east along latitude  35  degrees,  10 minutes
                         north;

                    (e)  then south along longitude 115 degrees, 45 minutes
                         west and west along the San Bernardino / Riverside
                         County Boundary(see Map 1).

               (7)  "Heat Input":  the chemical heat released due  to  fuel
                    combustion  in  a permit unit, using the higher heating
                    value of the fuel.   This does not include the sensible
                    heat of incoming combustion air.

               (8)  "High Annual Heat Input  Permit  Unit":   a permit unit
                    with  an  annual  heat  input greater than or equal  to
                    50,000 million Btu (MMBtu).

               (9)  "Higher Heating Value (HHV)":  the total heat liberated
                    per mass of fuel burned (Btu  per pound), when fuel and
                    dry  air  at  standard  conditions   undergo   complete
                    combustion  and  all resultant products are brought  to
                    standard conditions.

               (10) "Independent Power  Producer":   a power plant which is
                    not   directly   regulated   by   a  Public   Utilities
                    Commission, which provides power to an electric utility
                    rather than directly to rate-payers,  and  which  is  a
                    Qualifying  Small  Power Production Facility per Public
                    Utility Regulatory Policies  Act  regulations  (18  CFR
                    Ch.1, Subpart B).

               (11) "Low  Annual  Heat  Input  Permit Unit":  a permit unit
                    with an annual heat input less  than 50,000 million Btu
                    (MMBtu).

               (12) "NOx  Emissions"  (NOx):   the  sum of  any  oxides  of
                    nitrogen which can be measured in the flue gas.

               (13) "Parts per Million (by Volume)" (ppmv):   the number of
                    gas  molecules  of  a given species, or group,  in  one
                    million total gas molecules.

               (14) "Permit Unit":  any boiler,  steam generator or process
                    heater required to have a Permit to Operate pursuant to
                    District Rule 203.

               (15) "Process Heater":  any combustion  equipment fired with
                    any fuel, which transfers heat from combustion gases to
                    water  or  process  streams.  Process heater  does  not
                    include any dryers in which the material being dried is
                    in direct contact with the products of combustion, such
                    as:  cement or lime kilns,  glass  melting furnaces, or
                    smelters.

               (16) "Reasonably Available Control Technology"  (RACT):  the
                    lowest emission limitation that a particular  source is
                    capable  of  meeting  by  the  application  of  control
                    technology  that  is  reasonably  available considering
                    technological and economic feasibility.

               (17) "Rated  Heat  Input":   the  heat  input  capacity  (in
                    MMBtu/hr)  specified  on the nameplate  of  the  permit
                    unit, unless:

                    (a)  the permit unit is  limited by permit condition to
                         a  lesser  heat  input  than   specified   on  the
                         nameplate,  in  which  case the limiting condition
                         shall be used as the rated heat input; or

                    (b)  the permit unit is operated  above  the heat input
                         capacity specified on the nameplate, in which case
                         the  maximum  operated rate shall be used  as  the
                         rated heat input.

               (18) "Start-up  Period":    the   one   hour   time   period
                    immediately following a continuous period in which fuel
                    flow  to  the  permit  unit is zero, or shut off for 30
                    minutes or longer.

               (19) "Shut-down  Period":   the   one   hour   time   period
                    immediately preceding a continuous period in which fuel
                    flow  to  the  permit  unit is zero, or shut off for 30
                    minutes or longer.

               (20) "Solar  Power  Production  Facility":   an  independent
                    power producer which  is a Solar Thermal Powerplant per
                    Public Resources Code 25140.


          (C)  Requirements

               (1)  RACT  standard  versus  BARCT  standard  applicability:
                    RACT standards shall apply  to all permit units, unless
                    BARCT  standards  are  applicable   to  the  particular
                    existing permit unit.  BARCT standards  shall  apply to
                    any  existing permit units currently permitted to  emit
                    more than  five  tons per day or more than 250 tons per
                    year of NOx.
               (2)  An owner or operator  of  any permit unit(s) subject to
                    subsection (C)(3)(a) or (C)(4)(a)  below shall have the
                    option of complying with either the  ppmv or pounds per
                    million Btu (lbs/MMBtu) NOx emission limits.

               (3)  RACT Standards:

                    (a)  High annual heat input permit units, as defined in
                         Section (B), shall not emit:

                         (i)  carbon monoxide in excess of 400 ppmv; and

                         (ii) NOx  in  excess  of  70  ppmv,  and/or  0.084
                              lbs/MMBtu  of  heat  input, when operated  on
                              gaseous fuel; and

                         (iii)NOx  in  excess  of  115 ppmv,  and/or  0.150
                              lbs/MMBtu  of heat input,  when  operated  on
                              liquid and/or solid fuels; and

                         (iv) NOx  in  excess  of  the  heat-input weighted
                              average   of   the   limits   specified    in
                              (C)(3)(a)(ii) and (C)(3)(a)(iii), above, when
                              operated   on  combinations  of  gaseous  and
                              liquid and/or solid fuels.

                                             Sample calculation:

                              wherex = annual heat input from gaseous fuel
                                   y = annual heat input from liquid and/or
                              solid fuel

                    (b)  Low annual heat input  permit units, as defined in
                         Section (B), shall:

                         (i)  be operated in a manner that maintains stack-
                              gas oxygen (O2) concentrations  at  less than
                              or  equal to 3.0 percent by volume on  a  dry
                              basis; or

                         (ii) be operated  with  a  stack-gas  oxygen  trim
                              system  set  at 3.00  0.15 percent oxygen by
                              volume on a dry basis;  or

                         (iii)be tuned at least annually in accordance with
                              the procedure  described  in  Section  (I), a
                              modification    of   the   tuning   procedure
                              described in Section  (I)  as approved by the
                              APCO,   or  the  permit  unit  manufacturer's
                              specified  tune-up procedure, by a technician
                              that is qualified, to the satisfaction of the
                              Air Pollution  Control  Officer, to perform a
                              tune-up; or

                         (iv) be operated in compliance with the applicable
                              emission  levels  specified   in   subsection
                              (C)(3)(a).

               (4)  BARCT Standards:

                    (a)  High annual heat input permit units, as defined in
                         Section (B), shall not emit:

                         (i)  carbon monoxide in excess of 400 ppmv; and

                         (ii) NOx  in  excess  of  30  ppmv,  and/or  0.036
                              lbs/MMBtu   of  heat  input, when operated on
                              gaseous fuel; and

                         (iii)NOx  in  excess  of  40  ppmv,  and/or  0.052
                              lbs/MMBtu  of heat input,  when  operated  on
                              liquid and/or solid fuels ; and

                         (iv) NOx  in  excess  of  the  heat-input weighted
                              average   of   the   limits   specified    in
                              (C)(4)(a)(ii) and (C)(4)(a)(iii), above, when
                              operated   on  combinations  of  gaseous  and
                              liquid and/or solid  fuels.

                                             Sample calculation:

                              wherex = annual heat input from gaseous fuel
                                   y = annual heat input from liquid and/or
                              solid fuel

                    (b)  Low annual heat input  permit units, as defined in
                         Section (B) shall:

                         (i)  be operated in a manner that maintains stack-
                              gas  oxygen concentration  at  less  than  or
                              equal  to  3.0  percent  by  volume  on a dry
                              basis; or

                         (ii) be  operated  with  a  stack-gas  oxygen trim
                              system  set at 3.00  0.15 percent oxygen  by
                              volume on a dry basis;  or

                         (iii)be tuned at least annually in accordance with
                              the procedure  described  in  Section  (I), a
                              modification    of   the   tuning   procedure
                              described in Section  (I)  as approved by the
                              APCO,   or  the  permit  unit  manufacturer's
                              specified  tune-up procedure, by a technician
                              that is qualified, to the satisfaction of the
                              Air Pollution  Control  Officer, to perform a
                              tune-up; or

                         (iv) be operated in compliance with the applicable
                              emission  levels  specified   in   subsection
                              (C)(4)(a).

               (5)  General Equipment Requirements:

                    (a)  Owners   or   operators   of  permit  units  which
                         simultaneously  fire  combinations   of  different
                         fuels,  and  are  subject  to the requirements  of
                         subsection (C)(3)(a) or (C)(4)(a), shall:

                         (i)  install mass flow rate  meters  in  each fuel
                              line; or

                         (ii) install   volumetric   flow  rate  meters  in
                              conjunction  with  temperature  and  pressure
                              probes in each fuel line; or

                         (iii)maintain a fuel log  in  the  form and manner
                              prescribed and approved by the APCO.

                    (b)  Owners or operators of permit units  which  employ
                         flue-gas NOx reduction technology, and are subject
                         to  the  requirements  of  subsection (C)(3)(a) or
                         (C)(4)(a), shall:

                         (i)  install   meters  as  applicable   to   allow
                              instantaneous  monitoring  of the operational
                              characteristics    of   the   NOx   reduction
                              equipment; or

                         (ii) maintain  a  log of NOx  reduction  equipment
                              operational characteristics  in  the form and
                              manner prescribed and approved by the APCO.

                    (c)  Owners  or  operators  of  permit units which  are
                         subject to (C)(3)(b) or (C)(4)(b)  and  choose  to
                         comply   with   (C)(3)(b)(ii)   or  (C)(4)(b)(ii),
                         respectively,  shall  install  a stack-gas  oxygen
                         trim system.
          (D)  Exemptions

               (1)  During  periods  of  unexpected curtailment  of  normal
                    gaseous fuels, permit units subject to the requirements
                    of subsection (C)(3)(a)  or  (C)(4)(a)  which  normally
                    burn only gaseous fuel shall comply with a NOx emission
                    limit of either 150 ppmv or 0.215 pound per million Btu
                    of heat input when burning liquid or solid fuel.  (This
                    exemption  shall  not  exceed the period of natural gas
                    curtailment, and specifically  excludes  equipment  and
                    emission  testing  time  not  exceeding  48  hours  per
                    calendar year).

               (2)  Permit   units   which   are  located  at  solar  power
                    production   facilities  and   are   subject   to   the
                    requirements of  subsection (C)(3)(a) shall comply with
                    the following NOx emission limits:

                    (a)  125 ppmv, when  the permit unit is located at SEGS
                         VI or SEGS VII and  is operating at 40% or less of
                         rated heat input; and

                    (b)  80 ppmv, when the permit  unit  is located at SEGS
                         II and is operating at 40% or less  of  rated heat
                         input; and

                    (c)  those limits specified in (C)(3)(a), for all other
                         such permit units and operating conditions.

               (3)  The  provisions  of Section (C) of this rule shall  not
                    apply to permit units  which  have no annual heat input
                    (annual heat input equals zero).  The owner or operator
                    of  any permit unit who wishes to  claim  an  exemption
                    pursuant  to  this  subsection  shall  meet  the record
                    keeping requirements of this rule so as to be  able  to
                    prove the exemption status.


          (E)  Monitoring and Records

               (1)  Emissions Compliance Testing:

                    (a)  Frequency:    All   permit   units  covered  under
                         subsections  (C)(3) and (C)(4)  shall  demonstrate
                         compliance through emission compliance testing not
                         less than once every 12 months, except that permit
                         units complying  with subsection (C)(3)(b)(iii) or
                         (C)(4)(b)(iii) shall  be  tuned not less than once
                         every  12  months, and permit  units  claiming  an
                         exemption pursuant to subsection (D)(1) which burn
                         a secondary  fuel  for  less  than  720 cumulative
                         hours in the twelve month consecutive period prior
                         to  testing  shall  not  be  required  to  perform
                         compliance testing for that fuel.

                    (b)  Procedures:

                         (i)  Compliance  testing  required  by  this  rule
                              shall  follow  the  administrative procedures
                              outlined  in the District's  Compliance  Test
                              Procedural      Manual.      All     emission
                              determinations shall be made as stipulated in
                              the test protocol accepted by the District.

                         (ii) Emission determinations  shall  include, at a
                              minimum,   one   emission   compliance   test
                              conducted at 90% of the maximum  firing  rate
                              allowed  by  the District permit or at normal
                              operating  conditions   as   determined   and
                              approved by the APCO.

                         (iii)No    compliance   determination   shall   be
                              established   based  on  data  obtained  from
                              compliance  testing,   including   integrated
                              sampling methods, during a start-up period or
                              shut-down period.

                         (iv) All   ppmv   emission   limits  specified  in
                              subsections (C)(3)(a), (C)(4)(a)  and  (D)(1)
                              are  referenced  at  dry stack-gas conditions
                              and 3.0 percent by volume stack-gas oxygen.

                         (v)  All  lbs/MMBtu NOx emission  rates  shall  be
                              calculated  as pounds of nitrogen dioxide per
                              MMBtu of heat input.

                         (vi) All  emission   concentrations  and  emission
                              rates shall be based on hourly averages.

               (2)  Records and Reporting

                    (a)  For all permit units subject  to  this  rule,  the
                         owners/operators shall monitor and record for each
                         permit unit the HHV and cumulative annual usage of
                         each  fuel.  The  cumulative  annual usage of each
                         fuel  shall  be  monitored  from  utility  service
                         meters, purchase or tank fill records,  or  by any
                         other  acceptable methods, as approved by the  Air
                         Pollution  Control  Officer.   A  statement of the
                         heat input for the previous calendar year shall be
                         submitted to the District by March 1 each year.

                    (b)  For permit units exempt from subsection  (C)(3)(a)
                         or (C)(4)(a) in accordance with subsection (D)(1),
                         the  owner/operators shall monitor and record  for
                         each permit  unit  the  cumulative annual hours of
                         operation on each liquid or solid fuel.

                    (c)  All data shall be kept current  and  on site for a
                         minimum of two years, and provided to  District or
                         state personnel on request.

                    (d)  The owners or operators of permit units subject to
                         this  rule  shall  submit  all required compliance
                         test reports to the District.

                    (e)  For  each  permit unit complying  with  subsection
                         (C)(3)(b)(iii)    or    (C)(4)(b)(iii),    records
                         verifying that the tune-up has been performed  for
                         each  fuel  burned shall be maintained on site for
                         two years.  If  a different tune-up procedure from
                         that described in Section (I) is used, then a copy
                         of this procedure  shall  be  kept on site for two
                         years.  Such records shall be provided  on request
                         by the APCO.

                    (f)  Test   reports   shall   include  the  operational
                         characteristics  of  all  flue-gas  NOx  reduction
                         equipment.


          (F)  Test Methods

               (1)  Compliance  with the NOx, carbon  monoxide  and  oxygen
                    requirements of Section C shall be determined using the
                    following test methods:

                    (a)  Oxides of  Nitrogen  - EPA Method 7E or ARB Method
                         100

                    (b)  Carbon Monoxide - EPA Method 10 or ARB Method 100

                    (c)  Stack Gas Oxygen - EPA  Method  3  or  3A  or  ARB
                         Method 100

                    (d)  NOx  Emission Rate (Heat Input Basis) - EPA Method
                         19

               (2)  HHV determination shall be by one of the following test
                    methods:

                    (a)  ASTM D 2015-85 for solid fuels; or

                    (b)  ASTM  D  240-87  or  ASTM  D  2382-88  for  liquid
                         hydrocarbon fuels; or

                    (c)  ASTM D  1826-88,  or ASTM D 1945-81 in conjunction
                         with ASTM D 3588-89 for gaseous fuels.
          (G)  Compliance Schedule

               (1)  The owner or operator of  permit  units subject to this
                    rule   shall   fulfill  the  following  increments   of
                    progress:

                    (a)  On  or  before   February   28,  1995,  submit  an
                         Emissions Control Plan.

                    (b)  Install any required NOx reduction  technology  no
                         later  than May 31, 1995, unless such installation
                         was  demonstrated   to  be  impracticable  in  the
                         Emissions Control Plan.   Those  permit  units for
                         which   installation   by  May  31,  1995  is  not
                         practicable  shall  fulfill,  at  a  minimum,  the
                         following interim measures:

                         (i)  On  or before February  28,  1995,  submit  a
                              complete  application  to the District for an
                              Authority  to  Construct  the  NOx  reduction
                              technology; and

                         (ii) On or before May 31, 1995,  provide  evidence
                              that equipment has been ordered; and

                         (iii)On  or before January 31, 1996, take delivery
                              of equipment; and

                         (iv) Actual  NOx  reduction  technology  shall  be
                              installed  as  soon  as possible but no later
                              than March 31, 1996.

                    (c)  Demonstrate final compliance  with  all applicable
                         standards and requirements of the rule:

                         (i)  by  May  31, 1995 for permit units  with  NOx
                              control technology  in  place or permit units
                              subject to subsection (C)(3)(b) or (C)(4)(b);
                              or

                         (ii) within  six  months  of installation  of  NOx
                              reduction technology.

               (2)  The owner or operator of a permit  unit  which  becomes
                    subject to the requirements of subsection (C)(3)(a)  or
                    (C)(4)(a) by exceeding the annual heat input thresholds
                    in  subsection  (B)(8)  for  a  calendar  year,  or  by
                    operating the permit unit so that an exemption pursuant
                    to   (D)(3)   no  longer  applies,  shall  fulfill  the
                    following increments of progress:

                    (a)  On or before  December  31  of  the  calendar year
                         immediately  following  the  year that the  annual
                         heat input threshold was exceeded  or  the  permit
                         unit  commenced  operation,  submit  an  Emissions
                         Control  Plan  containing the information outlined
                         in subsection (B)(5).

                    (b)  No later than three  calendar  years following the
                         submission   of   the   Emissions  Control   Plan,
                         demonstrate final compliance  with  all applicable
                         standards and requirements of the rule.

               (3)  Failure to perform interim measures as set  forth  in a
                    submitted  Emissions  Control  Plan  shall constitute a
                    violation of this rule.


          (H)  Severability of Portions of this Rule

               If  any  portion  of  this  rule is found to be  invalid  or
               unenforceable, such finding shall  have  no  effect  on  the
               validity and enforceability of the remaining portions of the
               rule,  which  are severable and shall continue to be in full
               force and effect.


          (I)  Tuning Procedure

               (1)  Nothing in  these  Tuning Procedures shall be construed
                    to require any act or  omission  that  would  result in
                    unsafe  conditions  or  would  be  in  violation of any
                    regulation   or  requirement  established  by   Factory
                    Mutual,  Industrial   Risk   Insurers,   National  Fire
                    Prevention  Association,  the California Department  of
                    Industrial Relations (Occupational  Safety  and  Health
                    Division),  the  Federal Occupational Safety and Health
                    Administration,  or   other  relevant  regulations  and
                    requirements.

               (2)  Tuning Procedure for Forced-Draft Permit units[1]

                    (a)  Operate the permit  unit  at  the firing rate most
                         typical of normal operation.  If  the  permit unit
                         experiences  significant load variations   operate
                         it at its average firing rate.

                    (b)  At this firing rate, record stack gas temperature,
                         oxygen concentration,  and  CO  concentration (for
                         gaseous fuels) or smoke-spot number[2] (for liquid
                         fuels), and observe flame conditions  after permit
                         unit  operation  stabilizes  at  the  firing  rate
                         selected.  If the excess oxygen in the  stack  gas
                         is  at  the  lower  end  of  the  range of typical
                         minimum values,[3] and if the CO emissions are low
                         and there is no smoke, the permit unit is probably
                         operating  at near optimum efficiency  -  at  this
                         particular firing  rate.   However,  complete  the
                         remaining  portion  of this procedure to determine
                         whether still lower oxygen levels are practical.

                    (c)  Increase combustion air  flow to the furnace until
                         stack gas oxygen levels increase  by  one  to  two
                         percent  over the level measured in Step 2.  As in
                         Step  2, record  the  stack  gas  temperature,  CO
                         concentration  (for  gaseous fuels), or smoke-spot
                         number  (for  liquid  fuels),  and  observe  flame
                         conditions for these higher  oxygen  levels  after
                         boiler operation stabilizes.

                    (d)  Decrease  combustion  air flow until the stack gas
                         oxygen concentration is  at  the level measured in
                         Step  2.   From  this level gradually  reduce  the
                         combustion air flow,  in  small increments.  After
                         each increment, record the  stack gas temperature,
                         oxygen   concentration,   CO  concentration   (for
                         gaseous fuels) and smoke-spot  number  (for liquid
                         fuels).   Also,  observe the flame and record  any
                         changes in its condition.

                    (e)  Continue to reduce  combustion  air flow stepwise,
                         until one of these limits is reached:

                         (i)  Unacceptable flame conditions - such as flame
                              impingement on furnace walls or burner parts,
                              excessive    flame   carryover,   or    flame
                              instability.

                         (ii) Stack gas CO concentrations  greater than 400
                              ppmv.

                         (iii)Smoking at the stack.

                         (iv) Equipment-related limitations  -  such as low
                              windbox/furnace pressure differential,  built
                              in air-flow limits, etc.

                    (f)  Develop  an  O2/CO  curve  (for  gaseous fuels) or
                         O2/smoke curve (for liquid fuels) using the excess
                         oxygen and CO or smoke-spot number  data  obtained
                         at each combustion air flow setting.
                    (g)  From the curves prepared in Step 6, find the stack
                         gas oxygen levels where the CO emissions or smoke-
                         spot number equal the following values:

                    Fuel              Measurement                Value

                    Gaseous           CO Emissions               400 ppmv

                    #1 and #2 oils    smoke-spot number          number 1

                    # 4 Oil           smoke-spot number          number 2

                    # 5 Oil           smoke-spot number          number 3

                    Other oils        smoke-spot number          number 4

                    The above conditions are referred to as the CO or smoke
                    thresholds, or as the minimum excess oxygen levels.

                    Compare  this  minimum  value  of  excess oxygen to the
                    expected value provided by the combustion  permit  unit
                    manufacturer.    If   the   minimum   level   found  is
                    substantially  higher  than  the value provided by  the
                    combustion permit unit manufacturer, burner adjustments
                    can  probably  be made to improve  fuel  and  air  mix,
                    thereby allowing operations with less air.

                    (h)  Add 0.5 to  2.0  percent  to  the  minimum  excess
                         oxygen  level  found  in  Step  7 and reset burner
                         controls to operate automatically  at  this higher
                         stack  gas  oxygen  level.  This margin above  the
                         minimum oxygen level accounts for fuel variations,
                         variations   in   atmospheric   conditions,   load
                         changes, and nonrepeatability or play in automatic
                         controls.

                    (i)  If the load of the  combustion  permit unit varies
                         significantly  during  normal  operation,   repeat
                         Steps  1-8  for  firing  rates  that represent the
                         upper and lower limits of the range  of  the load.
                         Because control adjustments at one firing rate may
                         affect  conditions  at other firing rates, it  may
                         not be possible to establish  the  optimum  excess
                         oxygen level at all firing rates.  If this is  the
                         case, choose the burner control settings that give
                         the  best  performance  over  the  range of firing
                         rates.   If one firing rate predominates,  setting
                         should optimize conditions at the rate.

                    (j)  Verify that  the  new settings can accommodate the
                         sudden  load  changes  that  may  occur  in  daily
                         operation without  adverse  effects.   Do  this by
                         increasing   and  decreasing  load  rapidly  while
                         observing the  flame  and  stack.   If  any of the
                         conditions  in Step 5 result, reset the combustion
                         controls to provide  a  slightly  higher  level of
                         excess oxygen at the affected firing rates.  Next,
                         verify  these  new  settings in a similar fashion.
                         Then make sure that the final control settings are
                         recorded at steady-state  operating conditions for
                         future reference.

                    (k)  When  the above checks and adjustments  have  been
                         made, record  data  and attach combustion analysis
                         to permit unit records.   Indicate  the  name  and
                         title  of  the  person performing the tune-up, the
                         date  the tune-up  was  performed,  and  sign  the
                         record.

               (2)  Equipment Tuning  Procedure  for  Natural  Draft  Fired
                    Permit units

                    (a)  Preliminary Analysis

                         (i)  CHECK  THE OPERATING PRESSURE OR TEMPERATURE.
                              Operate   the   permit  unit  at  the  lowest
                              acceptable pressure  or temperature that will
                              satisfy the load demand.   This will minimize
                              heat  and  radiation losses.   Determine  the
                              pressure or  temperature that will be used as
                              a basis for comparative  combustion  analysis
                              before and after tuneup.

                         (ii) COMBUSTION  ANALYSIS.   Perform  an  "as  is"
                              combustion  analysis  (CO2,  O2, etc.) with a
                              warmed up permit unit at high  and  low fire,
                              if  possible.   In  addition to data obtained
                              from  combustion analysis,  also  record  the
                              following:

                              1.   Inlet fuel pressure at burner (at high &
                                   low fire); and

                              2.   Draft  above  draft  hood  or barometric
                                   damper   (at   high,  medium,  and   low
                                   settings); and

                              3.   Steam pressure,  water  temperature,  or
                                   process  fluid  pressure  or temperature
                                   entering and leaving the permit unit.

                              4.   Permit unit rate if meter is available.

                    (b)  Adjustments:   while  taking  combustion  readings
                         with a warmed up permit unit operated at the rated
                         heat  input,  perform  checks and  adjustments  as
                         follows:

                         (i)  Adjust permit unit  to  fire  at rate; record
                              fuel manifold pressure.

                         (ii) Adjust draft and/or fuel pressure  to  obtain
                              acceptable,  clean combustion at high, medium
                              and low firing  rates.   The  CO value should
                              always be below 400 ppmv at 3%  O2.  If CO is
                              high make necessary adjustments.

                         (iii)Check  to ensure permit unit light  offs  are
                              smooth and  safe.   A  reduced  fuel pressure
                              test  at  both  high  and low fire should  be
                              conducted    in    accordance     with    the
                              manufacturer's  instructions  and maintenance
                              manuals.

                         (iv) Check  and  adjust  operations of  modulation
                              controller.   Ensure  proper,  efficient  and
                              clean combustion through  the range of firing
                              rates.

                         When above adjustments and corrections  have  been
                         made, record all data.

                    (c)  Final  Test:   Perform a final combustion analysis
                         with a warmed up  permit  unit at high, medium and
                         low firing rates, whenever  possible.  In addition
                         to data from combustion analysis,  also  check and
                         record:

                         (i)  fuel pressure at burner (at high, medium  and
                              low settings); and

                         (ii) draft  above  draft hood or barometric damper
                              (at high, medium, and low settings); and

                         (iii)steam pressure, water temperature, or process
                              fluid pressure  or  temperature  entering and
                              leaving the permit unit; and

                         (iv) permit unit rate if meter is available.

                         When  the  above checks and adjustments have  been
                         made, record  data  and attach combustion analysis
                         to permit unit records.   Indicate  the  name  and
                         title  of  the  person performing the tune-up, the
                         date  the tune-up  was  performed,  and  sign  the
                         record.

          **FOOTNOTES**

          1 This tuning procedure  is based on a tune-up procedure developed
            by KVB, Inc. for the USEPA.
          2 The smoke-spot number can be determined with ASTM test method D-
            2156 or with the Bacharach method.
          3 Typical minimum oxygen levels  for  boilers at high firing rates
            are:
               1.  For natural gas:  0.5 - 3%;   2.  For liquid fuels:  2 -
               4%


                                                           MDAQMD Rule 1157
                                                Boilers and Process Heaters