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EPA Releases its Draft Maui Guidance

EPA today released its draft guidance on the Maui decision. This guidance opines on what discharges to groundwater may be regulated under NPDES. Here's a link to the EPA release: https://www.epa.gov/sites/production/files/2020-12/documents/draft_ow_maui_guidance_document_-_12.2020_-_epa-hq-ow-2020-0673.pdf


A quick review of the 8-page guidance shows that EPA is working hard to limit the scope of Maui. They make clear that regulated discharges are a subset of all discharges to groundwater. Draft Guidance at 6. They also add a new requirement to Maui's 7-part test. One should now also consider the design of the system that injects pollutants into hydrologically-connected groundwater. If the system is not engineered to direct pollutants to WOTUS, then the CWA does not apply Id. at 7. This arguably introduces an intent standard into a strict-liability statute. One could argue that even though the pollutants reach WOTUS, the system was not designed to put them there (e.g., a coal-fired power plant ash pond), so no permit is required. I doubt that was the Court's intent.


The Guidance also lays out a very vague and confusing test at page 6 for dilution and changes in chemistry as the pollutants transit from the point source to WOTUS. I would argue that minor dilution (which will always happen in groundwater) or transformation of the pollutants is of little importance. You still have pollutants discharging from a point source to WOTUS without a permit. Dilution over many miles to very low levels should be considered, but it's not all clear from this guidance.


This Guidance was clearly rushed through the system. They're looking at an imminent deadline for getting it published in the Federal Register in order for it to go final before the end of the administration. This is a complex issue that requires a lot of careful thought and vetting with EPA field staff. This administration generally writes these types of documents at the political level with no input from career staff, so they're missing out on advice from most of the people in the agency with the technical expertise and field experience. It'll be interesting to see what the Biden administration does with it, and that will depend in part on whether this goes final before its authors leave office.



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