Indiana Revision To Rules On POTW Interference By Industrial Discharges

Indiana Department of Environmental Management (IDEM) has proposed a revision to State rules related to industrial pretreatment of wastewater. The pretreatment rules apply to industrial wastes being discharged to a Publically Owned Treatment Works, or POTW. The existing definition of "interference" in State rules is more stringent than the federal definition. IDEM is proposing to amend 327 IAC 5-17-11 to be consistent with 40 CFR 403.3(k).


Existing state rule at 327 IAC 5-17-11 defines "interference" as occurring if one of three listed conditions occurs at the POTW due to a discharge or discharges from other sources. The listed conditions include a discharge or discharges that:

• inhibit or disrupt the POTW,
• cause a violation of any of the POTW's NPDES permit requirements, and
• prevent the use of the POTW's sewage sludge or its sludge disposal method.

The federal definition of "interference" ties the conditions and causing a violation of any requirement of the POTW's NPDES permit together so that all have to occur before interference has occurred


The rule change was preliminarily adopted on 08/10/2016, however an effective date is yet to be determined.




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