N.Y. Comp. Codes R. & Regs. tit. 6, § 231-3.5 – Source obligation.

(a) The issuance of a permit does not relieve any owner or operator of the responsibility to comply fully with applicable provisions of the State Implementation Plan.
(b) For the purposes of Subparts 231-7 and 231-8 of this Part only, at such time that a particular facility becomes a major facility or a modification becomes a NSR major modification solely by virtue of a relaxation in any enforceable limitation which was established after August 7, 1980, on the capacity of the facility or modification otherwise to emit a regulated NSR contaminant, such as a restriction on hours of operation, then the requirements of Subparts 231-7 and 231-8 of this Part, as applicable, apply to the facility as though construction had not yet commenced on the facility.
(c) Any owner or operator of a facility that proposes a project that involves a physical change or change in the method of operation that the owner or operator determines would be followed by a facility emissions increase that exceeds baseline actual emissions and that equals or exceeds any of the significant project thresholds in Subpart 231-13 of this Part, table 3, 4 or 6, must notify the department in writing of the proposed project prior to implementing the change if the owner or operator determines that the project does not constitute a modification because all the emission increases are attributable to independent factors in accordance with section 231-4.1(b)(42)(i)(c) of this Part. The notification shall include the following:
1. (1) a description of the change;
2. (2) the calculation of the projected emissions increase;
3. (3) the proposed date of the change; and
4. (4) an explanation of the factual basis for the conclusion that none of the projected emission increases are attributable to the proposed project.