11.722 Affirmative Defense.
(1) An industrial user shall have an affirmative defense to an enforcement action brought against it for noncompliance with the general prohibitions in Section 11.201(1) or the specific prohibitions in Sections 11.201(2)(a) through (2)(s) if it can prove that it did not know or have reason to know that its discharge would cause pass through or interference and that either:
(a) A local limit exists for each pollutant discharged and the user was in compliance with each limit directly prior to and during the pass through or interference; or
(b) No local limit exists, but the discharge did not change substantially in nature or constituents from the user’s prior discharge when the treatment plant was regularly in compliance with its NPDES permit, and in the case of interference, in compliance with applicable sludge use or disposal requirements.
(2) The intentional diversion of waste streams from any portion of an industrial user’s treatment facility shall be an affirmative defense to an enforcement action brought against the industrial user if the user can demonstrate that such a bypass was unavoidable to prevent loss of life, personal injury, or severe property damage. In order to be eligible for the affirmative defense, the industrial user must demonstrate that there was no feasible alternative to the bypass and submit notice of the bypass as required by 40 CFR Part 403.17.
The establishment of an affirmative defense under the provisions of this section does not relieve the user of liability for damages or extraordinary costs incurred by the POTW as a result of the discharge.