Extraordinary circumstances checklist
Before applying a CE, the agency screens for extraordinary circumstances that may make a normally excluded action likely to have a reasonably foreseeable significant adverse effect. Under CEQ's guidance, one being present bars the CE only if the agency's procedures say so; the agency documents its reasoning, and if the CE does not fit, prepares an EA or EIS[3].
DOE bars segmenting a proposal into small parts to fit a CE[11]. USDA's procedures list resources to screen, including[12]:
- Federally listed threatened or endangered species, designated critical habitat, and species or habitat proposed for listing
- Floodplains, wetlands and other sensitive areas
- Special sources of water, such as sole-source aquifers and municipal watersheds
- Designated areas, such as wilderness, wild and scenic rivers and inventoried roadless areas
- Historic, archeological or architectural properties, including those eligible for the National Register
- American Indian and Alaska Native religious or cultural sites
Documented categorical exclusions: does every CE need a decision memo?
No. USDA splits its list into CEs that need no NEPA documentation (7 CFR 1b.4(c)) and CEs that do (1b.4(d))[5]. For the second group, the responsible official signs a finding of applicability and no extraordinary circumstance, or FANEC[12]. Moving the Forest Service's CEs into 7 CFR part 1b did not change which categories need one[4].
DOE documents every CE determination for actions in appendix B, on a categorical exclusion determination form, and posts it online, generally within two weeks[11][13]. At FAA, actions likely to affect sensitive resources or facing known controversy may warrant a documented CATEX, in no prescribed format[14]. FHWA's (d)-list CEs need documentation that their conditions are met[7].
Categorical exclusion examples
CEs are most of the Forest Service's NEPA work: 32,208 of its 39,372 decisions signed from 2005 to 2021, or 82%, were CE decision memos, with a median of 110 days from scoping to signature[15]. NEPA timelines compares EAs and EISs.
Below are the five categories cited most in a random sample of 601 Forest Service decision memos, with the old 36 CFR 220.6 citation[16] and the 7 CFR 1b.4 code[5]. Each carries conditions in its full text; read the whole category before relying on it. 12 signed decision memos show one example per category.
| Category | 36 CFR 220.6 | 7 CFR 1b.4 | Share of memos | Signed example |
|---|---|---|---|---|
| Special uses under 20 acres | (e)(3) | USDA-28d-USFS | 27% | Verizon Communication Site, Datil: propane tank and generator pads, Cibola, 2025[17] |
| Timber stand or wildlife habitat improvement | (e)(6) | USDA-30d-USFS, set aside by a court on January 13, 2026[4] | 14% | Bee Canyon: fence keeping cattle out of riparian habitat, Apache-Sitgreaves, 2025[18] |
| Trails | (e)(1) | USDA-26d-USFS | 9% | Enoree Palmetto Trail: 6.3 miles moved off forest roads, Francis Marion and Sumter, 2025[19] |
| Special use permit reissued for administrative changes only | (e)(15), later (d)(11) | USDA-28c-USFS, which needs no memo | 9% | Lovcom, Inc.: expired communication use lease replaced, Bighorn, 2020[20] |
| Short-term mineral investigations | (e)(8) | USDA-32d-USFS | 4% | Cuddy Mountain: exploratory drilling at 17 sites from existing roads, Payette, 2025[21] |