(a) For existing affected sources, you must conduct initial performance tests no later than 180 days after the compliance date that is specified for your source in §63.8683 and according to the provisions in §63.7(a)(2).

(b) As an alternative to the requirement specified in paragraph (a) of this section, you may use the results of a previously-conducted emission test to demonstrate compliance with the emission limitations in this subpart if you demonstrate to the Administrator's satisfaction that:

(1) No changes have been made to the process since the time of the emission test; and

(2) The operating conditions and test methods used during testing conform to the requirements of this subpart; and

(3) The control device and process parameter values established during the previously-conducted emission test are used to demonstrate continuous compliance with this subpart; and

(4) The previously-conducted emission test was completed within the last 60 months.

(c) For new sources, you must demonstrate initial compliance no later than 180 calendar days after April 29, 2003 or within 180 calendar days after startup of the source, whichever is later.

[68 FR 24577, May 7, 2003, as amended at 85 FR 14549, Mar. 12, 2020]