The CAT X Files



The “categorical exclusion” (CATX) is a means by which action agencies exclude whole categories of their actions from NEPA review.  The CATX was unprecedented when it was established by the Council on Environmental Quality in its 1978 regulations, see 40 C.F.R. § 1508.4, and this page collects the Lab’s posts about and research into this now most pervasive NEPA device.


The Grandfather CATXdecision tree.NEPA

Can an agency keep categorically excluding a pipeline from NEPA review just because it’s already in the ground?  Over time, that pipeline’s risk of failure increases.  When will such a risk be significant enough that the continued application of a CATX is ‘arbitrary and capricious’?  This lawsuit in Michigan may hold the answer.

The CATX to Help Wind

Often, judging agency’s action as one without significant impact in the environment turns on the legal or administrative quality of the action.  And that can be hard to judge. In one recent case involving the nature of a long-term versus a short-term permit, the court took great care with how long-term permits allocate the burden of uncertainty in ways that might lead to more unchecked environmental harm.

The Wildland Fuel CATX Gone Bust

The Forest Service has doubled down on “fuel reduction” projects on its lands.  The Ninth Circuit’s continuing scrutiny of the Service’s continuing effort to skip projects around NEPA is yielding a shocking degree of uncertainty and ignorance where fuel reduction projects are being executed.