SAN DIEGO COUNTY AIR POLLUTION CONTROL DISTRICT

RULE 260.42b - STANDARD FOR SULFUR DIOXIDE
(Effective 3-14-89; Rev. Effective 9/21/93)

(a) Except as provided in Sections (b), (c), or (d) of this rule on and after the date on which the performance test is completed or required to be completed under Rule 260.8 of this Regulation, whichever date comes first, no owner or operator of an affected facility that combusts coal or oil shall cause to be discharged into the atmosphere any gases that contain sulfur dioxide in excess of 10 percent (0.10) of the potential sulfur dioxide emission rate (90 percent reduction) and that contain sulfur dioxide in excess of the emission limit determined according to the following formula:

Only the heat input supplied to the affected facility from the combustion of coal and oil is counted under this rule. No credit is provided for the heat input to the affected facility from the combustion of natural gas, wood, municipal-type solid waste, or other fuels or heat input to the affected facility from exhaust gases from another source, such as gas turbines, internal combustion engines, kilns, etc.

(b) On and after the date on which the performance test is completed or is required to be completed under Rule 260.8 of this Regulation, whichever comes first, no owner or operator of an affected facility that combusts coal refuse alone in a fluidized bed combustion steam generating unit shall cause to be discharged into the atmosphere any gases that contain sulfur dioxide in excess of 20 percent of the potential sulfur dioxide emission rate (80 percent reduction) and that contain sulfur dioxide in excess of 520 ng/J (lbs/million BTU) heat input. If coal or oil is fired with coal refuse, the affected facility is subject to Sections (a) or (d) of this rule, as applicable.

(c) On and after the date on which the performance test is completed or is required to be completed under Rule 260.8 of this Regulation, whichever comes first, no owner or operator of an affected facility that combusts coal or oil, either alone or in combination with any other fuel, and that uses an emerging technology for the control of sulfur dioxide emissions, shall cause to be discharged into the atmosphere any gases that contain sulfur dioxide in excess of 50 percent of the potential sulfur dioxide emission rate (50 percent reduction) and that contain sulfur dioxide in excess of the emission limit determined according to the following formula:

Only the heat input supplied to the affected facility from the combustion of coal and oil is counted under this rule. No credit is provided for the heat input to the affected facility from the combustion of natural gas, wood, municipal-type solid waste, or other fuels, or from the heat input to the affected facility from exhaust gases from another source, such as gas turbines, internal combustion engines, kilns, etc.

(d) On and after the date on which the performance test is completed or required to be completed under Rule 260.8 of this Regulation, whichever comes first, no owner or operator of an affected facility listed in Subsections (d)(1), (d)(2), or (d)(3), of this rule shall cause to be discharged into the atmosphere any gases that contain sulfur dioxide in excess of 520 ng/J (1.2 lbs/million BTU) heat input if the affected facility combusts coal, or 215 ng/J (0.50 lbs/ million BTU) heat input if the affected facility combusts oil other than low sulfur oil. The following affected facilities under this section are not subject to percent reduction requirements: (Rev. Effective 9-21-93)

  1. Affected facilities that have any annual capacity factor for coal and oil of 30 percent (0.30) or less and are subject to a federally enforceable permit limiting the operation of the affected facility to an annual capacity factor for coal and oil to 30 percent (0.30) or less;
  2. Affected facilities located in a noncontinental area; and
  3. Affected facilities combusting coal or oil, alone or in combination with any other fuel, in a duct burner as part of a combined cycle system where 30 percent (0.30) or less of the heat input to the steam generating unit is from combustion of coal and oil in the duct burner and 70 percent (0.70) or more of the heat input to the steam generating unit is from the exhaust gases entering the duct burner.

(e) Except as provided in Section (f) of this rule, compliance with the emission limits, fuel oil sulfur limits, and/or percent reduction requirements under this rule are determined on a rolling 60-minute average basis. (Rev. Effective 9-21-93)

(f) Except as provided in Subsection (j)(2) of this rule, compliance with the emission limits or fuel oil sulfur limits under this rule is determined on a 24-hour average basis for affected facilities that have a federally enforceable permit limiting the annual capacity factor for oil to 10 percent or less, combust only low sulfur oil, and do not combust any other fuel. (Effective 9-21-93)

(g) Except as provided in Section (i) of this rule, the sulfur dioxide emission limits and percent reduction requirements under this section apply at all times, including periods of startup, shutdown, and malfunction.

(h) Reductions in the potential sulfur dioxide emission rate through fuel pretreatment are not credited toward the percent reduction requirement under Section (c) of this rule unless:

  1. Fuel pretreatment results in a 50 percent or greater reduction in potential sulfur dioxide emissions and
  2. Emissions from the pretreated fuel (without combustion or post combustion sulfur dioxide control) are equal to or less than the emission limits specified in Section  (c) of this rule.

(i) An affected facility subject to Sections (a), (b), or (c) of this rule may combust low sulfur oil or natural gas when the sulfur dioxide control system is not being operated because of malfunction or maintenance of the sulfur dioxide control system.

(j) Affected facilities combusting only low sulfur oil are not subject to the percent reduction requirements in any section of this rule. The owner or operator of an affected facility combusting low sulfur oil shall demonstrate that the oil meets the definition of low sulfur oil by: (Effective 9-21-93)

  1. following the performance testing procedures as described in Rules 260.45b(c) or 260.45b(d), and following the monitoring procedures as described in Rules 260.47b(a) or 260.47b(b) to determine sulfur dioxide emission rate or fuel oil sulfur content; or
  2. maintaining fuel receipts as described in Rule 260.49b(r).