NR 207.12(4)(4) Relaxing an interim effluent limitation or an elg-based limitation or standard. Interim effluent limitations, standards, and conditions and ELG-based effluent limitations and standards that have taken effect in a permit may be relaxed in a reissued, revoked and reissued, or modified permit if the requirements in sub. (1) (a) and (b) are met and both of the following are met: NR 207.12(4)(a)(a) Circumstances upon which the previous permit was based have materially and substantially changed since the time the permit was issued. NR 207.12(4)(b)(b) Changes have occurred that would constitute cause for a permit modification or revocation and reissuance under ch. NR 203. NR 207.12 HistoryHistory: CR 17-002: cr. Register April 2018 No. 748, eff. 5-1-18; correction in (3) (a) 2. b. under s. 13.92 (4) (b) 7., Stats., Register April 2018.