The intentional diversion of waste streams from any portion of an individual 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, and there were no feasible alternatives to the bypass, such as the use of auxiliary treatment facilities, retention of untreated wastes or maintenance during normal periods of equipment downtime. This condition is not satisfied if adequate back up equipment should have been installed in the exercise of reasonable engineering judgment to prevent a bypass which occurred during normal periods of equipment downtime or preventive maintenance. In order to be eligible for the affirmative defense, the industrial user must demonstrate that there was no feasible alternative to the bypass, and meet all required conditions of 40 C.F.R. § 403.17, including notification of the bypass. (Ord. 106 § 9(8), passed 10-9-2012; Code 2014 § 52.09(H))