SDAPCD RULE X-TT STD.OF PERF. FOR METAL COIL SURF. COATING          
LAST REVISED 11/03/92

          
          SUBPART TT - Standard of Performance for Metal Coil Surface
                       Coating (Delegation Effective 4/24/84:  
                       Rev. Effective 11/3/92))


               RULE 260.460.  APPLICABILITY AND DESIGNATION OF AFFECTED
                              FACILITY

               (a)  The provisions of this subpart apply to the following
          affected facilities in a metal coil surface coating operation:
          each prime coat operation, each finish coat operation, and each
          prime and finish coat operation combined when the finish coat is
          applied wet on wet over the prime coat and both coatings are
          cured simultaneously.

               (b)  This subpart applies to any facility identified in
          Section (a) of this rule that commences construction,
          modification, or reconstruction after January 5, 1981.


               RULE 260.461.  DEFINITIONS

               All terms used in this subpart not defined below are given
          the same meaning as in the Act or in Subpart A of this
          Regulation.

               (a)  "Coating" means any organic material that is applied to
          the surface of metal coil.

               (b)  "Coating Application Station" means that portion of the
          metal coil surface coating operation where the coating is applied
          to the surface of the metal coil.  Included as part of the
          coating application station is the flashoff area between the
          coating application station and the curing oven.

               (c)  "Curing Oven" means the device that uses heat or
          radiation to dry or cure the coating applied to the metal coil.

               (d)  "Finish Coat Operation" means the coating application
          station, curing oven, and quench station used to apply and dry or
          cure the final coating(s) on the surface of the metal coil.
          Where only a single coating is applied to the metal coil, that
          coating is considered a finish coat.

               (e)  "Metal Coil Surface Coating Operation" means the
          application system used to apply an organic coating to the
          surface of any continuous metal strip with thickness of 0.15
          millimeter (mm) (0.006 in.) or more that is packaged in a roll or
          coil.

               (f)  "Prime Coat Operation" means the coating application
          station, curing oven, and quench station used to apply dry or
          cure the initial coating(s) on the surface of the metal coil.

               (g)  "Quench Station" means that portion of the metal coil
          surface coating opera-tion where the coated metal coil is cooled,
          usually by a water spray, after baking or curing.

               (h)  "VOC Content" means the quantity, in kilograms per
          liter of coating solids, of volatile organic compounds (VOC's) in
          a coating.

               All symbols used in this subpart not defined below are given
          the same meaning as in the Act and in Subpart A of this
          Regulation.

          Ca   =    the VOC concentration in each gas stream leaving the
                    control device and entering the atmosphere (parts per
                    million by volume, as carbon).

          Cb   =    the VOC concentration on each gas stream entering the
                    control device (parts per million by volume, as
                    carbon).

          Ci   =    VOC concentration in each gas stream emitted directly
                    to the atmosphere (parts per million by volume, as
                    carbon).

          Dc   =    density of each coating, as received (kilograms per
                    liter).

          Dd   =    density of each VOC-solvent added to coatings
                    (kilograms per liter).

          Dr   =    density of VOC-solvent recovered by an emission control
                    device (kilograms per liter).

          E    =    VOC destruction efficiency of the control device
                    (fraction).

          F    =    the proportion of total VOC's emitted by an affected
                    facility that enters the control device (fraction).

          G    =    volume-weighted average mass of VOC's in coatings
                    consumed in a calendar month per unit volume of coating
                    solids applied (kilograms per liter).

          Lc   =    the volume of each coating consumed, as received
                    (liters).

          Ld   =    the volume of each VOC-solvent added to coatings
                    (liters).

          Lr   =    the volume of VOC-solvent recovered by an emission
                    control device (liters).

          Ls   =    the volume of coatings solids consumed (liters).

          Md   =    the mass of VOC-solvent added to coatings (kilograms).

          Mo   =    the mass of VOC's in coatings consumed, as received
                    (kilograms).

          Mr   =    the mass of VOC's recovered by an emission control
                    device (kilograms).

          N    =    the volume-weighted average mass of VOC emissions to
                    the atmosphere per unit volume of coating solids
                    applied (kilograms per liter).

          Qa   =    the volumetric flow rate of each gas stream leaving the
                    control device and entering the atmosphere (dry
                    standard cubic meters per hour).

          Qb   =    the volumetric flow rate of each gas stream entering
                    the control device (dry standard cubic meters per
                    hour).

          Qr   =    the volumetric flow rate of each gas stream emitted
                    directly to the atmosphere (dry standard cubic meters
                    per hour).

          R    =    the overall VOC emission reduction achieved for an
                    effected facility (fraction).

          S    =    the calculated monthly allowable emission limit
                    (kilograms of VOC per liter of coating solids applied).

          Vs   =    the proportion of solids in each coating, as received
                    (fraction by volume).

          Wo   =    the proportion of VOC's in each coating, as received
                    (fraction by weight).


               RULE 260.462.  STANDARDS FOR VOLATILE ORGANIC COMPOUNDS

               (a)  On and after the date on which Rule 260.8 requires a
          performance test to be completed, each owner or operator subject
          to this subpart shall not cause to be discharged into the
          atmosphere more than:

                    (1)  0.28 kilogram VOC per liter (kg VOC/l) of coating
               solids applied for each calendar month for each affected
               facility that does not use an emission control device(s); or

                    (2)  0.14 kg VOC/l of coating solids applied for each
               calendar month for each effected facility that continuously
               uses an emission control device(s) operated at the most
               recently demonstrated overall efficiency; or

                    (3)  10 percent of the VOC's applied for each calendar
               month (90 percent emission reduction) for each affected
               facility that continuously uses an emission control
               device(s) operated at the most recently demonstrated overall
               efficiency; or

                    (4)  A value between 0.14 (or a 90 percent  emission
               reduction) and 0.28 kg VOC/l of coating solids applied for
               each calendar month for each affected facility that
               intermittently uses an emission control device operated at
               the most recently demonstrated overall efficiency.


               RULE 260.463.  PERFORMANCE TEST AND COMPLIANCE
                              PROVISIONS

               The owner or operator of an affected facility shall conduct
          performance tests and provide compliance calculations as
          specified in Part 60, Chapter I, Title 40, Code of Federal
          Regulations, Section 60.463.


               RULE 260.464.  MONITORING OF EMISSIONS AND OPERATIONS

               (a)  Where compliance with the numerical limit specified in
          Rule 260.462 (a)(1) and (2) is achieved through the use of low
          VOC-content coatings without the use of emission control devices
          or through the use of higher VOC-content coatings in conjunction
          with emission control devices, the owner or operator shall
          compute and record the average VOC content of coatings applied
          during each calendar month for each affected facility, according
          to the equations provided in Rule 260.463.

               (b)  Where compliance with the limit specified in Rule
          260.462(a)(4) is achieved through the intermittent use of
          emission control devices, the owner or operator shall compute and
          record for each affected facility the average VOC content of
          coatings applied during each calendar month according to the
          equations provided in Rule 260.463.

               (c)  If thermal incineration is used, only, each owner or
          operator subject to the provisions of this subpart shall install,
          calibrate, operate, and maintain a device that continuously
          records the combustion temperature of any effluent gases
          incinerated to achieve compliance with Rule 260.462(a)(2), (3) or
          (4).  This device shall have an accuracy of +2.5 C or +0.75
          percent of the temperature being measured expressed in degrees
          Celsius, whichever is greater.  Each owner or operator shall also
          record all periods (during actual coating operations) in excess
          of 3 hours during which the average temperature in any thermal
          incinerator used to control emissions from an affected facility
          remains more than 28 C (50 F) below the temperature at which
          compliance with Rule 260.462(a)(2), (3), or (4) was demonstrated
          during the most recent measurement of incinerator efficiency
          required by Rule 260.8.  The records required by Rule 260.7 shall
          identify  each such occurrence and its duration.  If catalytic
          incineration is used, the owner or operator shall install,
          calibrate, operate, and maintain a device to monitor and record
          continuously the gas temperature both upstream and downstream of
          the incinerator catalyst bed.  This device shall have an accuracy
          of +2.5 C or +0.75 percent of the temperature being measured
          expressed in degrees Celsius, whichever is greater.  During
          coating operations, the owner or operator shall record all
          periods in excess of 3 hours where the average difference between
          the temperature upstream and downstream of the incinerator
          catalyst bed remains below 80 percent of the temperature differ-
          ence at which compliance was demonstrated during the most recent
          measurement of incinerator efficiency or when the inlet
          temperature falls more than 28 C (50 F) below the temperature
          at which compliance with Rule 260.462 (a)(2), (3), or (4) was
          demonstrated during the most recent measurement of incinerator
          efficiency required by Rule 260.8.  The records required by Rule
          260.7 shall identify each such occurrence and its duration.

               RULE 260.465.  REPORTING AND RECORDKEEPING
                              REQUIREMENTS  (Rev. Effective 11/3/92)

               (a)  Where compliance with the numerical limit specified in
          Rule 260.462 (a)(1), (2), or (4) is achieved through the use of
          low VOC-content coatings without emission control devices or
          through the use of higher VOC-content coatings in conjunction
          with emission control devices, each owner or operator subject to
          the provisions of this subpart shall include in the initial com-
          pliance report required by Rule 260.8 the weighted average of the
          VOC content of coatings used during a period of one calendar
          month for each affected facility.  Where compliance with Rule
          260.462(a)(4) is achieved through the intermittent use of a
          control device, reports shall include separate values of the
          weighted average VOC content of coatings used with and without
          the control device in operation.

               (b)  Where compliance with Rule 260.462(a), (2), (3), or (4)
          is achieved through the use of an emission control device that
          destroys VOC's, each owner or operator subject to the provisions
          of this subpart shall include the following data in the initial
          compliance report required by Rule 260.8.

                    (1)  The overall VOC destruction rate used to attain
               compliance with Rule 260.462 (a)(2), (3), and (4) and the
               calculated emission limit used to attain compliance with
               Rule 260.462(a)(4); and

                    (2)  The combustion temperature of the thermal
               incinerator or the gas temperature, both upstream and
               downstream of the incinerator catalyst bed, used to attain
               compliance with Rule 260.462(a)(2), (3), or (4).

               (c)  Following the initial performance test, the owner or
          operator of an affected facility shall identify, record, and
          submit a written report, as specified in Rule 260.7(c), to the
          Control Officer every calendar quarter of each instance in which
          the volume-weighted average of the local mass of VOC's emitted to
          the atmosphere per volume of applied coating solids (N) is
          greater than the limit specified under Rule 269.462.  If no such
          instances have occurred during a particular quarter, a report
          stating this shall be submitted to the Control Officer
          semiannually.

               (d)  The owner or operator of each affected facility shall
          also submit reports semiannually to the Control Officer when the
          incinerator temperature drops as defined under Rule 269.464(c).
          If no such periods occur, the owner or operator shall state this
          in the report.

               (e)  Each owner or operator subject to the provisions of
          this subpart shall maintain at the source, for a period of at
          least 2 years, records of all data and calculations used to
          determine monthly VOC emissions from each affected facility and
          to determine the monthly emission limit,where applicable.  Where
          compliance is achieved through the use of thermal incineration,
          each owner or operator shall maintain, at the source, daily
          records of the incinerator combustion temperature.  If catalytic
          incineration is used, the owner or operator shall maintain at the
          source daily records of the gas temperature, both upstream and
          downstream of the incinerator catalyst bed.

               RULE 260.466.  TEST METHODS AND PROCEDURES

               Performance tests shall be conducted as specified in Part
          60, Chapter I, Title 40, Code of Federal Regulations, Section
          60.466.