50 CFR 10.4 - When regulations apply.
The regulations of this subchapter B shall apply to all matters arising after the effective date of such regulations, with the following exceptions:
(a) Civil penalty proceedings. Except as otherwise provided in § 11.25, the civil penalty assessment procedures contained in this subchapter B shall apply only to any proceeding instituted by notice of violation dated subsequent to the effective date of these regulations, regardless of when the act or omission which is the basis of a civil penalty proceeding occurred.
(b) Permits. The regulations in this subchapter B shall apply to any permit application received after the effective date of the appropriate regulations in this subchapter B and, insofar as appropriate, to any permit which is renewed after such effective date.