A user shall have an affirmative defense to an enforcement action brought against it for noncompliance with the general prohibitions in §
117-69 of this Part
5 or the specific prohibitions in §
117-70 of this Part
5, except §
117-70A(1),
(2) and
(8), if it can prove that it did not know, or have reason to know, that its discharge, alone or in conjunction with discharges from other sources, 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 limits exist, but the discharge did not change
substantially in nature or constituents from the user's prior discharge
when the Lower Perkiomen Valley Regional Sewer Authority as control
authority was regularly in compliance with the NPDES permit and, in
the case of interference, was in compliance with applicable sludge
use or disposal requirements.