Area of Critical Environmental Concern

{{About|the Federal ACEC program|the state-level ACEC program in Massachusetts|Area of Critical Environmental Concern (Massachusetts)}}

File:Jawbone-Butterbredt Area of Critical Environmental Concern signs near SR178 2016-04-05.jpg]]

Areas of Critical Environmental Concern (ACEC) is a conservation ecology program in the Western United States, managed by the Bureau of Land Management (BLM). The ACEC program was conceived in the 1976 Federal Lands Policy and Management Act (FLPMA), which established the first conservation ecology mandate for the BLM. The FLPMA mandate directs the BLM to protect important riparian corridors, threatened and endangered species habitats, cultural and archeological resources, as well as unique scenic landscapes that the agency assesses as in need of special management attention.

Criteria

To be considered a potential ACEC an area must meet criteria of both relevance and importance.BLM Manual 1613, Areas of Critical Environmental Concern, section 1613.1.11

=Relevance=

An area meets the relevance criteria of an ACEC if it contains one or more of the following:

A significant historic, cultural, or scenic value;
A fish or wildlife resource;
A natural process or system (including but not limited to areas supporting rare, endemic, relict, or endangered plant species, or rare geological features);
Natural hazards (most notably areas of avalanche, unstable soils, rockfall).

=Importance=

An area meets the importance criteria if it is characterized by one or more of the following:

Has more than locally significant qualities;
Has qualities or circumstances that make it fragile, sensitive, irreplaceable, rare, unique;
Has been recognized as warranting protection to satisfy national priority concerns or to carry out the mandates of the Federal Land Policy and Management Act;
Has qualities which warrant concern about safety and public welfare;
Poses a significant threat to human life and safety, or to property.

Designated ACECs

=Alaska=

Sukakpak Mountain (2944 acres){{cite web | url=https://sdms.ak.blm.gov/metadata/acec_nad83.faq.html | title=Area of Critical Environmental Concern (ACEC) - Designated }}

=Arizona=

Arizona Strip Proposed Plan/FEIS, 2007. Chapter 3: Affected Environment, Areas of Critical Concern. Bureau of Land Management. [http://www.nps.gov/lake/parkmgmt/upload/FEIS_CHAPTER_3.pdf]{{dead link|date=June 2025|bot=medic}}{{cbignore|bot=medic}} (Accessed 2012-01-30){{Cite web|url=https://eplanning.blm.gov/epl-front-office/eplanning/planAndProjectSite.do?methodName=dispatchToPatternPage¤tPageId=99653|title=Yuma Field Office Record of Decision and Approved Resource Management Plan|accessdate=August 20, 2023}}

Witch Pool (279 acres)
Nampaweap (535 acres)
Pakoon (76,014 acres)
Beaver Dam Slope (51,197 acres)
Virgin River Corridor (8,075 acres)
Virgin Slope (39,931 acres)
Little Black Mountain (241 acres)
Fort Pearce (916 acres)
Marble Canyon (11,012 acres)
Johnson Springs (2,464 acres)
Lost Spring Mountain (8,262 acres)
Moonshine Ridge (5,095 acres)
Dripping Springs
Sears Point

=California=

Afton Canyon
Big Marias[https://eplanning.blm.gov/public_projects/lup/68418/87828/105163/Yuma-ROD-ARMPcomplete.pdf Yuma Rod] eplanning.blm.gov
Bodie Bowl
Carrizo Plain{{cite web |url=http://www.blm.gov/ca/st/en/fo/bakersfield/Programs/planning/rmpcontents/rmpcarrizo.html |title=Carrizo Plain |website=www.blm.gov |access-date=2016-10-03}}
Clear Creek Serpentine
Conway Summit[https://blmca.sites.usa.gov/2015/10/27/hunters-moon-and-aspen-conway-summit/ Conway Summit] usa.gov {{Dead link|date=October 2019 |bot=InternetArchiveBot |fix-attempted=yes }}
East Mesa
Fort Ord
Indian Pass
Jawbone-Butterbredt Area of Critical Environmental Concern
Joaquin Rocks{{cite web |url=http://www.blm.gov/ca/st/en/fo/hollister/recreation/Joaquin_Ridge.html |title=Joaquin Rocks |website=www.blm.gov |access-date=2016-10-03}}
Lake Cahuilla Shoreline[https://eplanning.blm.gov/public_projects/lup/66459/20012656/250017248/ACEC_Lake_Cahuilla_Subregion.pdf Lake Cahuilla subregion] blm.gov
North Algodones Dunes
Ocotillo
Pilot Knob
Plank Road
The Red Hills of Tuolumne County{{cite web|url=http://www.blm.gov/ca/st/en/fo/folsom/redhillshomepg1.html |title=Red Hills ACEC, Mother Lode Field Office, Bureau of Land Management California |access-date=2010-06-26 |url-status=dead |archive-url=https://web.archive.org/web/20101221220511/http://www.blm.gov/ca/st/en/fo/folsom/redhillshomepg1.html |archive-date=2010-12-21 }} . accessed 2010-06-22.
Salton Sea Hazardous
San Sebastian Marsh/San Felipe Creek
Serpentine{{cite web |url=http://www.blm.gov/ca/st/en/fo/hollister/recreation/clear_creek_recreation/serpentine_acec.html |title=Serprentine |website=www.blm.gov |access-date=2016-10-03}}
Singer Geoglyphs
West Mesa
Yuha Basin

= Colorado =

File:Colorado in United States.svg}} in the {{nobreak|United States of America}}.|alt=A map showing the location of the U.S. State of Colorado.]]

{{cite web |url=https://www.blm.gov/programs/planning-and-nepa/planning-101/special-planning-designations/acec |title=Areas of Critical Environmental Concern |author= |website=United States. Bureau of Land Management |access-date=2019-04-30 }}The actual list is in an Excel file [https://www.blm.gov/sites/blm.gov/files/planningandnepa_aceclist.xlsx here].

Adobe Badlands{{cite web|url=http://www.blm.gov/pgdata/etc/medialib/blm/co/field_offices/uncompahgre_field/rmp/rmp_docs.Par.96192.File.dat/Draft%20ACEC%20Report%20071510.pdf|title=Draft Evaluation of Proposed and Existing Areas of Critical Environmental Concern for the Uncompahgre Planning Area|publisher=United States Department of the Interior, Bureau of Land Management|date=June 2010|access-date=October 22, 2012}} – {{convert|6783|acre|km2|2}}
American Basin{{cite web|url=http://www.blm.gov/co/st/en/BLM_Programs/land_use_planning/acec.print.html |title=BLM Colorado: Land Use Planning - Areas of Critical Environmental Concern |publisher=United States Department of the Interior, Bureau of Land Management |date=August 12, 2008 |access-date=October 22, 2012 |url-status=dead |archive-url=https://web.archive.org/web/20100530120513/http://www.blm.gov/co/st/en/BLM_Programs/land_use_planning/acec.print.html |archive-date=May 30, 2010 }} – {{convert|1595|acre|km2|2}}
Anasazi Culture – {{convert|156000|acre|km2|0}}
Arkansas Canyonlands – {{convert|23921|acre|km2|2}}
Atwell Gulch – {{convert|2900|acre|km2|2}}
Badger Wash – {{convert|1520|acre|km2|2}}
Barger Gulch Heritage Area – {{convert|535|acre|km2|2}}
Beaver Creek – {{convert|12081|acre|km2|2}}
Black's Gulch – {{convert|800|acre|km2|2}}
Blanca Wildlife Habitat Area – {{convert|8600|acre|km2|1}}
Blue Hill – {{convert|4178|acre|km2|2}}
Browns Canyon – {{convert|11697|acre|km2|2}}
Bull Gulch – {{convert|10214|acre|km2|2}}
Coal Draw – {{convert|1840|acre|km2|2}}
Coal Oil Rim – {{convert|3210|acre|km2|2}}
Cucharas Canyon – {{convert|1866|acre|km2|2}}
Cumbres and Toltec Railroad – {{convert|3824|acre|km2|2}}
Debris Hazard – {{convert|7126|acre|km2|2}}
Deep Creek – {{convert|2470|acre|km2|2}}
Deer Gulch – {{convert|1810|acre|km2|2}}
Dillon Pinnacles – {{convert|532|acre|km2|2}}
Droney Gulch – {{convert|705|acre|km2|2}}
Duck Creek – {{convert|3430|acre|km2|2}}
Dudley Bluffs – {{convert|1630|acre|km2|2}}
East Douglas Creek – {{convert|47610|acre|km2|2}}
Elephant Rocks – {{convert|1338|acre|km2|2}}
Escalante Canyon – {{convert|1895|acre|km2|2}}
Fairview – {{convert|377|acre|km2|2}}
Garden Park National Natural Landmark – {{convert|2728|acre|km2|2}}
Glenwood Springs Debris Flow Hazard Zones – {{convert|6100|acre|km2|2}}
Grand Hogback – {{convert|4300|acre|km2|2}}
Grape Creek – {{convert|15978|acre|km2|2}}
Gunnison Gravels – {{convert|5|acre|km2|2}}
Gunnison Sage Grouse – {{convert|22000|acre|km2|2}}
Gypsum Valley – {{convert|13135|acre|km2|2}}
Hardscrabble-East Eagle – {{convert|4200|acre|km2|2}}
Indian Creek – {{convert|2300|acre|km2|2}}
Irish Canyon – {{convert|11680|acre|km2|2}}
Juanita Arch – {{convert|1600|acre|km2|2}}
Kremmling – {{convert|674|acre|km2|2}}
Kremling Ammonite Site Research Natural Area – {{convert|160|acre|km2|2}}
Laramie River – {{convert|1783|acre|km2|2}}
Los Mogotes – {{convert|33456|acre|km2|2}}
Lower Colorado River – {{convert|9000|acre|km2|0}}
Lower Greasewood Creek – {{convert|210|acre|km2|2}}
Lyons Gulch – {{convert|400|acre|km2|2}}
McCoy Fan Delta – {{convert|1500|acre|km2|2}}
McElmo Rare Lizard and Snake – {{convert|427|acre|km2|2}}
Moosehead Mountain – {{convert|8940|acre|km2|2}}
Mosquito Pass – {{convert|4036|acre|km2|2}}
Mount Logan Foothills – {{convert|4000|acre|km2|2}}
Mt. Garfield – {{convert|2400|acre|km2|2}}
Native Plant Community – {{convert|4577|acre|km2|2}}
Needle Rock – {{convert|80|acre|km2|2}}
North Park Natural Area – {{convert|4444|acre|km2|2}}
North Park Phaceila – {{convert|300|acre|km2|2}}
North Sand Hills – {{convert|486|acre|km2|2}}
Oil Spring Mountain – {{convert|18260|acre|km2|2}}
Phantom Canyon – {{convert|6096|acre|km2|2}}
Pyramid Rock – {{convert|470|acre|km2|2}}
Rajadero Canyon – {{convert|3632|acre|km2|2}}
Raven Ridge – {{convert|4980|acre|km2|2}}
Red Cloud Peak – {{convert|5947|acre|km2|2}}
Rio Grande – {{convert|2830|acre|km2|2}}
Roan and Carr Creeks – {{convert|33600|acre|km2|2}}
Rough Canyon – {{convert|1470|acre|km2|2}}
Ryan Gulch – {{convert|1440|acre|km2|2}}
San Luis Hills/Flattop – {{convert|29261|acre|km2|2}}
San Miguel River – {{convert|20964|acre|km2|2}}
Sheep Creek Uplands – {{convert|3900|acre|km2|2}}
Sinbad Valley – {{convert|6400|acre|km2|2}}
Slumgullion National Natural Landmark – {{convert|1407|acre|km2|2}}
South Beaver Creek – {{convert|4565|acre|km2|2}}
South Cathedral Bluffs – {{convert|1330|acre|km2|2}}
South Shale Ridge – {{convert|27800|acre|km2|2}}
The Palisade – {{convert|19178|acre|km2|2}}
Thompson Creek – {{convert|4286|acre|km2|2}}
Trickle Mountain – {{convert|44521|acre|km2|2}}
Troublesome Creek – {{convert|998|acre|km2|2}}
Unaweep Seep Research Natural Area – {{convert|37|acre|km2|2}}
West Antelope Creek – {{convert|28215|acre|km2|2}}
White River Riparian – {{convert|950|acre|km2|2}}
Yanks Gulch/Upper Greasewood Creek – {{convert|2680|acre|km2|2}}

=Idaho=

= Montana =

File:Humbug Spires WSA (9469767136).jpg

(For more detailed descriptions of the following sites see){{cite web|last=Bureau of Land Management Montana/Dakotas|title=ACEC Status Report|url=http://www.blm.gov/mt/st/en/prog/planning/acec.print.html|access-date=2012-01-01}}

Acid Shale-Pine Forest (endemic plant community, {{convert|2463|acre|km2}}, Lewistown Office)
Ash Creek Divide (paleo, {{convert|7931|acre|km2}}, Miles City Office)
Azure Cave (cave resources, bats; {{convert|140|acre|km2}}, Malta Office)
Battle Butte (cultural, {{convert|120|acre|km2}}, Miles City)
Bear Creek Flats (wildlife, oldgrowth pine, recreation, {{convert|564|acre|km2}}, Missoula Office)
Beaverhead Rock (historic petroglyphs, {{convert|120|acre|km2}}, Dillon Office)
Big Bend of the Milk River (archaeological resources {{convert|2120|acre|km2}}, Malta)
Big Sheep Mountain (cultural, {{convert|360|acre|km2}}, Miles City)
Bitter Creek (vegetation, landscape; {{convert|59600|acre|km2}}, Malta){{cite web|last=Northern Plains Conservation Network |title=Bitter Creek/Grasslands National Park |url=http://www.npcn.net/index.php/pages/bitter-creek/ |access-date=2012-01-01 |url-status=dead |archive-url=https://web.archive.org/web/20120129020105/http://www.npcn.net/index.php/pages/bitter-creek/ |archive-date=2012-01-29 }}
Black-footed ferret (wildlife, {{convert|11166|acre|km2}}, Miles City)
Blue Lake (home to axoloti, rare form of tiger salamander; {{convert|430|acre|km2}}, Dillon)
Block Mountain (geological education, {{convert|8661|acre|km2}}, Dillon)
Bridger Fossil (paleo, {{convert|575|acre|km2}}, Billings Office)
Bug Creek (paleo, {{convert|3840|acre|km2}}, Miles City)
Castle Butte (cultural, {{convert|185|acre|km2}}, Billings)
Centennial Mountains (wildlife migration route, rare plants, grizzly bear, lynx, & wolf; {{convert|40715|acre|km2}}, Dillon)
Centennial Sandhills (sand dunes, sensitive plants; {{convert|1040|acre|km2}}, Dillon)
Collar Gulch (cutthroat trout, {{convert|1618|acre|km2}}, Lewistown)
Cow Creek (geological, scenic; {{convert|14000|acre|km2}}, Lewistown)
East Pryor Mountains (wildlife, wild horses, paleo; {{convert|29500|acre|km2}}, Billings)
Elkhorn Mountains (historic & cultural sites, wildlife; {{convert|50431|acre|km2}}, Butte Office)
Everson Creek (Stone Age archaeological site, {{convert|8608|acre|km2}}, Dillon)
Finger Buttes (scenic, {{convert|1520|acre|km2}}, Miles City)
Four Dances (cultural, scenic, peregrine falcon habitat; {{convert|765|acre|km2}}, Billings)
Hell Creek (paleo, {{convert|19169|acre|km2}}, Miles City)
Hoe (cultural, {{convert|144|acre|km2}}, Miles City)
Howrey Island (wildlife, {{convert|321|acre|km2}}, Miles City)
Humbug Spires (scenic, wildlife, vegetation; {{convert|8374|acre|km2}}, Butte)
Judith Mountains Scenic Area (scenic, wildlife, recreation; {{convert|3702|acre|km2}}, Lewistown)
Jordan Bison Kill (cultural, {{convert|160|acre|km2}}, Miles City Office)
Kevin Rim (wildlife, cultural, recreation; {{convert|4657|acre|km2}}, Great Falls Office)
Meeteetse Spires (rare plants, scenery; {{convert|960|acre|km2}}, Billings){{cite web|last=The Conservation Fund |title=Saving Montana's Meeteetse Spires |url=http://www.conservationfund.org/news/meeteetse_spires_montana |access-date=2012-01-01 |url-status=dead |archive-url=https://web.archive.org/web/20111121224506/http://conservationfund.org/news/meeteetse_spires_montana |archive-date=2011-11-21 }}
Mountain Plover (wildlife, vegetation; {{convert|24730|acre|km2}}, Malta)
Muddy Creek/Big Sheep Creek (scenic, cultural; {{convert|13097|acre|km2}}, Dillon)
Petroglyph Canyon (cultural, {{convert|240|acre|km2}}, Billings)
Piping Plover (wildlife, {{convert|16|acre|km2}}, Miles City)
Pompeys Pillar (historic, cultural, recreation; {{convert|470|acre|km2}}, Billings)
Powder River Depot (cultural, {{convert|1386|acre|km2}}, Miles City)
Prairie Dog Towns, (black-footed ferret reintroduction site, {{convert|12346|acre|km2}}, Malta)
Rattler Gulch Limestone Cliffs (scenic, {{convert|20|acre|km2}}, Missoula office. See Garnet Range for description)
Reynolds Battlefield (cultural, {{convert|336|acre|km2}}, Miles City)
Ringing Rocks (unique geology, {{convert|160|acre|km2}}, Butte Office)
Sand Arroyo (paleo, {{convert|9056|acre|km2}}, Miles City)
Seline (cultural, {{convert|80|acre|km2}}, Miles City)
Sleeping Giant (recreation, wildlife, scenic; {{convert|11679|acre|km2}}, Butte Office)
Smoky Butte (geology, recreation; {{convert|80|acre|km2}}, Miles City)
Square Butte (cultural, scenic, geologic; {{convert|1947|acre|km2}}, Lewistown)
Squaw Rock (wildlife, scenic, recreation; {{convert|640|acre|km2}}, Missoula)
Sweetgrass Hills (Cultural, wildlife, recreation; {{convert|7952|acre|km2}}, Great Falls)
Stark Site (cultural, {{convert|800|acre|km2}}, Billings)
Virginia City, Montana Historic District (historic, {{convert|513|acre|km2}}, Dillon)
Weatherman Draw (cultural, {{convert|4268|acre|km2}}, Billings)

=Nevada=

Ash Meadows
Beaver Dam Slope
Condor Canyon
Ivanpah
Mormon Mesa
Piute/Eldorado
Rainbow Gardens
River Mountains

=New Mexico=

Sombrillo
La Cienega[http://www.blm.gov/nm/st/en/fo/New_Mexico_State_Office/features/la_cienega_acec_expansion.html Community Celebrates Expansion of La Cienega ACEC] {{webarchive |url=https://web.archive.org/web/20080922235702/http://www.blm.gov/nm/st/en/fo/New_Mexico_State_Office/features/la_cienega_acec_expansion.html |date=September 22, 2008 }}, United States Department of the Interior, Bureau of Land Management, Press Release dated 2007-08-23, accessed 2008-07-06.
[http://www.blm.gov/nm/st/en/prog/recreation/farmington/Simon_Canyon_ACEC.html Simon Canyon]
Florida Mountains
Sacramento Escarpment
Three Rivers Petroglyph
Alamo Hueco Mountains
Bear Creek
Blue Spring
Pecos River Canyon Complex
Big Hatchet Mountains
Cowboy Spring
Granite Gap
Guadalupe Canyon
Chosa Draw
Cookes Range
Gila Lower Box
Gila Middle Box
Alkali Lakes
Apache Box
Central Peloncillo Mountains
Uvas Valley
Black Grama
Cornudas Mountain
Wind Mountain
Alamo Mountain

= Oregon =

{{cite web|url=http://www.blm.gov/or/plans/wopr/ACEC/coobay_existing.php|title=ACEC Existing - Coos Bay Oregon/Washington BLM|publisher=blm.gov|access-date=2016-04-15}}

Wassen Creek (Natural systems and botanical values, {{convert|3,397|acre|km2}}, Coos Bay Office)
North Spit (Botanical, wildlife, and cultural values, {{convert|710|acre|km2}}, Coos Bay Office)
North Fork Coquille River (Natural systems; botanical fish values, {{convert|311|acre|km2}}, Coos Bay Office)
Tioga Creek (Natural systems, {{convert|42|acre|km2}}, Coos Bay Office)
Cherry Creek (Natural systems and botanical values, {{convert|592|acre|km2}}, Coos Bay Office)
China Wall (Natural systems; botanical and cultural values, {{convert|303|acre|km2}}, Coos Bay Office)
Upper Rock Creek (Natural systems and botanical values, {{convert|472|acre|km2}}, Coos Bay Office)
New River (Botanical, wildlife, fish and cultural values, {{convert|1135|acre|km2}}, Coos Bay Office)
North Fork Hunter Creek (Natural systems; botanical and cultural values, {{convert|1925|acre|km2}}, Coos Bay Office)
Hunter Creek Bog (Natural systems and botanical values, {{convert|721|acre|km2}}, Coos Bay Office)
North Fork Chetco River (Natural systems; and botanical, fish, and cultural values {{convert|603|acre|km2}}, Coos Bay Office)
Upper and Lower Table Rock{{cite web|url=http://www.blm.gov/or/resources/recreation/tablerock/index.php|title=Welcome to the Table Rocks Oregon/Washington BLM|publisher=blm.gov|access-date=2016-04-15}}

= Utah =

[http://ostseis.anl.gov/documents/dpeis/index.cfm Draft Oil Shale and Tar Sands Resource Management Plan Amendments to Address Land Use Allocations in Colorado, Utah, and Wyoming and Programmatic Environmental Impact Statement, Volume 1] {{webarchive |url=https://web.archive.org/web/20090512104519/http://ostseis.anl.gov/documents/dpeis/index.cfm |date=May 12, 2009 }}, United States Department of the Interior, Bureau of Land Management, dated December 2007, accessed 2008-04-22.