Authority: IC 13-14-8; IC 13-15-1-2; IC 13-15-2-1; IC 13-18-3

Affected: IC 13-18-4; IC 13-18-19

Sec. 4. (a) If the discharger demonstrates to the satisfaction of the commissioner that thermal effluent limitations required under section 301 or 306 of the CWA are more stringent than necessary to assure the protection and propagation of a balanced, indigenous community of shellfish, fish and wildlife in and on the body of water into which the discharge is made, less stringent alternative thermal limitations may be established for the discharge. This demonstration must show that the alternative effluent limitations desired by the discharger, considering the cumulative impact of its thermal discharge together with all other significant impacts on the species affected, will assure the protection and propagation of a balanced, indigenous community of shellfish, fish and wildlife in and on the body of water into which the discharge is to be made.

(b) In determining whether or not the protection and propagation of the affected species will be assured, the commissioner may consider any information contained or referenced in any applicable thermal water quality criteria and supplemental information published by the administrator under section 304(a) of the CWA, or any other information he deems relevant.

(c)(1) Existing dischargers may base their demonstration upon the absence of prior appreciable harm in lieu of predictive studies. Any such demonstrations shall show:

1. (A) that no appreciable harm has resulted from the thermal component of the discharge (taking into account the interaction of such thermal component with other pollutants, such as oxygen-demanding pollutants and toxic pollutants, and the additive effect of other thermal sources) to a balanced, indigenous community of shellfish, fish and wildlife in and on the body of water into which the discharge has been made; or
2. (B) that, despite the occurrence of such previous harm, the desired alternative effluent limitations (or appropriate modifications thereof) will nevertheless preclude the occurrence of further appreciable harm and, thus, assure the protection and propagation of a balanced, indigenous community of shellfish, fish and wildlife in and on the body of water into which the discharge is made.

(2) In determining whether or not prior appreciable harm has occurred, the commissioner shall consider length of time in which the applicant has been discharging and the nature of the discharge.

(Water Pollution Control Division; 327 IAC 5-7-4; filed Sep 24, 1987, 3:00 pm: 11 IR 649; readopted filed Jan 10, 2001, 3:23 p.m.: 24 IR 1518; readopted filed Nov 21, 2007, 1:16 p.m.: 20071219-IR-327070553BFA; readopted filed Jul 29, 2013, 9:21 a.m.: 20130828-IR-327130176BFA; readopted filed Oct 18, 2024, 1:57 p.m.: 20241113-IR-327230810RFA)