Section 327IAC5-18-3. Affirmative defense

   An industrial user shall have an affirmative defense in any action brought against the industrial user alleging a violation of the prohibitions established in section 2 of this rule if the industrial user can demonstrate that:

(1) it did not know or have reason to know that its discharge, alone or in conjunction with a discharge from another source, would cause pass through or interference; and

(2) a local limit designed to prevent pass through or interference in accordance with section 2 of this rule:

(A) was developed for each pollutant in the industrial user’s discharge that caused pass through or interference, and the industrial user was in compliance with each such local limit directly prior to and during the pass-through or interference; or

(B) was not developed for the pollutant that caused the pass through or interference, and the industrial user’s discharge, directly prior to and during the pass through or interference, had not changed substantially in nature or constituents from its usual discharge condition when the POTW was regularly in compliance with the applicable:

(i) NPDES permit requirements; and

(ii) requirements for sewage sludge use or disposal, in the case of interference.

(Water Pollution Control Division; 327 IAC 5-18-3; filed Oct 10, 2000, 3:02 p.m.: 24 IR 298)