(a) For purposes of this section, a source's baseline is defined as the annual emissions that are calculated assuming full compliance with the adopted requirements of this chapter and using data representative of actual operations in 1990 or thereafter for all variables necessary to calculate annual emissions for the identified source.
  (1) For an alternate means of control (AMOC) application exclusively utilizing a source that existed prior to January 1, 1990, the AMOC application shall use data representative of actual operations in 1990.
  (2) For an AMOC application utilizing a source that was created on or after January 1, 1990, the AMOC application shall use data representative of actual operations for the two years prior to the application for the AMOC, or other representative years, as determined by the executive director.
  (3) For an AMOC application utilizing a source exempted from this chapter or with no applicable adopted requirements, or for a source whose actual annual emissions were less than the annual emissions calculated assuming full compliance with the adopted requirements, calculations will be based on actual annual emissions.
(b) The AMOC applicant shall determine annual emissions limits for each source included in the AMOC plan by utilizing the best available data and good engineering practice, which may include the use of statistical techniques to address variations in the data.
(c) For any source not controlled as otherwise specifically required by this chapter where an applicable adopted requirement exists, the AMOC applicant shall calculate credits needed by subtracting the source's baseline from the source's annual emissions limit under the AMOC plan. This difference shall then be multiplied by the appropriate factor in §115.911(3) of this title (relating to Criteria for Approval of Alternate Means of Control Plans), to determine the credits that must be generated by other sources.
(d) For a source controlled beyond the requirements of this chapter, or for a source exempted from or with no applicable adopted control requirement in this chapter, the AMOC applicant shall calculate the amount of emission reduction credits generated by subtracting the source's annual emissions limit under the AMOC plan from the source's baseline, less any reductions that are generated for purposes discussed in §115.911(6) of this title.
(e) For all sources included in the AMOC plan, the AMOC applicant will sum the total of credits needed and the total of credits generated to establish that the credits generated exceed the credits needed.
(f) The maximum potential to emit shall be the maximum daily emissions that the source could emit subject to any physical, operational and regulatory limitations.

Source Note: The provisions of this §115.912 adopted to be effective August 9, 1994, 19 TexReg 5719; amended to be effective May 16, 2002, 27 TexReg 4113