SAN DIEGO COUNTY AIR POLLUTION CONTROL DISTRICT

RULE 361.15 - MODIFICATION
(Delegation Effect.: 11-8-76: Rev. Effect.: 1-13-87)

(a) Except as provided under Section (d) of this rule, any physical or operational change to a stationary source which results in an increase in the rate of emission to the atmosphere of a hazardous pollutant to which a standard applies shall be considered a modification.

(b) Upon modification, an existing source shall become a new source for each hazardous pollutant for which the rate of emission to the atmosphere increases and to which a standard applies.

(c) Emission rate shall be expressed as kg/hr for any hazardous pollutant discharged into the atmosphere for which a standard is applicable. The Control Officer shall use the following to determine the emission rate:

(1) Emission factors as specified in the background information document (BID) for the applicable standard, or in the latest issue of "Compilation of Air Pollutant Emission Factors", EPA Publication No. AP-42, or other emission factors determined by the Control Officer to be superior to AP-42 emission factors, in cases where use of emission factors demonstrates that the emission rate will clearly increase or clearly not increase as a result of the physical or operational change.

(2) Material balances, monitoring data, or manual emission tests in cases where use of emission factors, as referenced in Subsection (c)(1) of this rule, does not demonstrate to the Control Officer's satisfaction that the emission rate will clearly increase or clearly not increase as a result of the physical or operational change, or where an interested person demonstrates to the Control Officer's satisfaction that there are reasonable grounds to dispute the result obtained by the Control Officer using emission factors. When the emission rate is based on results for manual emission tests or monitoring data, the procedures specified in Appendix C of 40 CFR Part 60 shall be used to determine whether an increase in emission rate has occurred. Tests shall be conducted under such conditions as the Control Officer shall specify to the owner or operator. At least three tests runs must be conducted before and at least three after the physical or operational change. If the Control Officer approves, the results of the emission tests required in Rule 361.13(a) may be used for the test runs to be conducted before the physical or operational change. All operating parameters which may affect emissions must be held constant to the maximum degree feasible for all test runs.

(d) The following shall not by themselves, be considered modifications under this regulation:

(1) Maintenance, repair, and replacement which the Control Officer determines to be routine for a source category.

(2) An increase in production rate of a stationary source, if that increase can be accomplished without a capital expenditure on the stationary source.

(3) An increase in the hours of operation.

(4) Any conversion to coal that meets the requirements specified in Section 111(a)(8) of the Act.

(5) The relocation or change in ownership of a stationary source. However, such activities must be reported in accordance with Rule 361.10(c).