Case was not made moot by agency's withdrawal of an enforcement order, where the underlying determination of jurisdiction remained, since it was not absolutely clear that the agency would not seek to reinstate the order.
Although the government enjoys a presumption of good faith in voluntary cessation, it must demonstrate that its change is entrenched or permanent.
Court did not abuse its discretion in admitting memo postdating the relevant decision, since the memo summarizes the same information that the agency relied upon, rather than being a post hoc justification.
Under Supreme Court precedent, EPA jurisdiction over wetlands requires a significant nexus with navigable waters, rather than the freer standard set out by the plurality in that case, since the first standard is a logical subset of the plurality's rule.
Agency's conculsion that painiffs' wetlands have a sufficient nexus to navigable waters wasn't arbitrary, and was supported by the record.
https://cdn.ca9.uscourts.gov/datastore/opinions/2021/08/16/19-35469.pdf