40 CFR 124.63 – Procedures for variances when EPA is the permitting authority
(a) In States where EPA is the permit issuing authority and a request for a variance is filed as required by § 122.21, the request shall be processed as follows:
(1)(i) If, at the time, that a request for a variance based on the presence of fundamentally different factors or on section 301(g) of the CWA is submitted, the Regional Administrator has received an application under § 124.3 for issuance or renewal of that permit, but has not yet prepared a draft permit under § 124.6 covering the discharge in question, the Administrator (or his delegate) shall give notice of a tentative decision on the request at the time the notice of the draft permit is prepared as specified in § 124.10, unless this would significantly delay the processing of the permit. In that case the processing of the variance request may be separated from the permit in accordance with paragraph (a)(3) of this section, and the processing of the permit shall proceed without delay.
(ii) If, at the time, that a request for a variance under sections 301(c) or 302(b)(2) of the CWA is submitted, the Regional Administrator has received an application under § 124.3 for issuance or renewal of that permit, but has not yet prepared a draft permit under § 124.6 covering the discharge in question, the Regional Administrator, after obtaining any necessary concurrence of the EPA Deputy Assistant Administrator for Water Enforcement under § 124.62, shall give notice of a tentative decision on the request at the time the notice of the draft permit is prepared as specified in § 124.10, unless this would significantly delay the processing of the permit. In that case the processing of the variance request may be separated from the permit in accordance with paragraph (a)(3) of this section, and the processing of the permit shall proceed without delay.
(2) If, at the time that a request for a variance is filed the Regional Administrator has given notice under § 124.10 of a draft permit covering the discharge in question, but that permit has not yet become final, administrative proceedings concerning that permit may be stayed and the Regional Administrator shall prepare a new draft permit including a tentative decision on the request, and the fact sheet required by § 124.8. However, if this will significantly delay the processing of the existing draft permit or the Regional Administrator, for other reasons, considers combining the variance request and the existing draft permit inadvisable, the request may be separated from the permit in accordance with paragraph (a)(3) of this section, and the administrative disposition of the existing draft permit shall proceed without delay.
(3) If the permit has become final and no application under § 124.3 concerning it is pending or if the variance request has been separated from a draft permit as described in paragraphs (a) (1) and (2) of this section, the Regional Administrator may prepare a new draft permit and give notice of it under § 124.10. This draft permit shall be accompanied by the fact sheet required by § 124.8 except that the only matters considered shall relate to the requested variance.