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A CAIR SO2 opt-in unit must be a unit that:
(a) Is located in a State that submits, and for which the Administrator approves, a State implementation plan revision in accordance with §51.124(r)(1), (2), or (3) of this chapter establishing procedures concerning CAIR opt-in units;
(b) Is not a CAIR SO2 unit under §97.204 and is not covered by a retired unit exemption under §97.205 that is in effect;
(c) Is not covered by a retired unit exemption under §72.8 of this chapter that is in effect and is not an opt-in source under part 74 of this chapter;
(d) Has or is required or qualified to have a title V operating permit or other federally enforceable permit; and
(e) Vents all of its emissions to a stack and can meet the monitoring, recordkeeping, and reporting requirements of subpart HH of this part.