Billings and Pompeys Pillar National Monument

Resource Management Plan Revision

FACT SHEET: Special Designations

Program Contact: Carolyn Sherve-Bybee, RMP Team Lead (406) 896-5234

This Draft RMP/EIS addresses a variety of special designations mandated by a number of laws, regulations, and 

policies, as well as a range of associated management actions to protect important resource values. Included in this 

plan are Areas of Critical Environmental Concern (ACECs), wilderness study areas (WSA), wild and scenic rivers

(WSR), National Historic Trails (NHT), and the Pryor Mountain Wild Horse Range (PMWHR).

Areas of Critical Environmental Concern (ACECs)

Section 202(c)(3) of Federal Land Policy and Management Act mandates that priority be given to the designation 

and protection of ACECs. These areas are defined in section 103(a) as areas where special management attention is 

required to protect and prevent irreparable damage to important values, resources, systems or processes, or to protect 

life and safety from natural hazards. An ACEC is a BLM designation and only applies to BLM public lands. This 

draft RMP/EIS addresses both existing and new/proposed ACECs, and associated management actions to protect the 

ACEC values (see Appendix E ACECs). 

This table summarizes the number of ACECs and total acres proposed by alternative.

Areas of Critical Environmental Concern

Alternative A

(No Action) Alternative B Alternative C Alternative D(Preferred)

9 ACECs

37,896 acres

12 ACECs

181,175 acres

11 ACECs

67,079 acres

11 ACECs

38,786 acres

This table shows each ACEC, relevant and important values, and acres proposed by alternative.

Areas of Critical Environmental Concern

Relevant & 

Important Values

Alternative A

(No Action) Alternative B Alternative C Alternative D(Preferred)

Pompeys Pillar 

National 

Monument and 

ACEC

Cultural, Historic, 

Geologic 432 acres

Bridger Fossil 

Area ACEC

Paleontological

values 577 acres

Castle Butte 

ACEC Cultural values 184 acres

East Pryor 

ACEC

Wild horses and 

wildlife habitat, 

cultural, 

paleontological

values, and special 

status plants and 

animals

29,550 acres 8,301 acres 32,767 acres 11,122 acres
Four Dances 

Natural Area 

ACEC

Safety hazards, 

cultural, historic, and 

scenic values, 

peregrine falcon 

nesting

784 acres

Grove Creek 

ACEC

Cultural values and 

Special Status Plants 0 acres 8,251 acres 9,445 acres 8,251 acres

Meeteetse 

Spires ACEC

Cultural values and 

Special Status Plants 965 acres 1,523 acres 2,173 acres 1,523 acres

Petroglyph 

Canyon ACEC Cultural values 240 acres

Pryor Foothills 

Research 

Natural Area 

ACEC

Special Status Plants, 

rare plant 

communities, 

cultural values

0 acres 958 acres 7,401 acres 2,606 acres

Stark Site 

ACEC Cultural values 799 acres

Weatherman 

Draw ACEC Cultural values 4,365 acres 4,986 acres 12,277 acres

Greater SageGrouse Habitat 

ACEC

Protect Greater SageGrouse habitat 0 acres 154,140 acres 0 acres

The table below summarizes other special areas addressed in the draft plan, including Wilderness Study Areas, Wild 

and Scenic Rivers, National Historic Trails, and the Pryor Mountain Wild Horse Range.

Special Designations

Alternative A

(No Action)

Alternative B Alternative C Alternative D

(Preferred)

Wilderness Study 

Areas

4 WSAs

28,631 acres

National Historic 

Trails

Nez Perce National Historic Trail: 5 miles

Lewis and Clark National Historic Trail: 3 miles

Pryor Mountain 

Wild Horse 

Range: Herd 

Management Area

24,595 BLM surface 

acres

(37,494 acres all 

ownerships – BLM, 

USFS, NPS, and 

private)

23,204 BLM 

surface acres

(31,153 acres all 

ownerships –

BLM, USFS, NPS, 

and private)

28,622 BLM surface 

acres

(44,855 acres all 

ownerships – BLM, 

USFS, NPS, and 

private)

27,094 BLM surface 

acres

(39,944 acres all 

ownerships – BLM, 

USFS, NPS, and 

private)

Wild and Scenic 

Rivers

7 eligible river 

segments (14.08

total miles)

7 eligible and 

suitable river 

segments (14.08 

total miles)

7 eligible river 

segments (14.08 

total miles)

2 eligible and 

suitable river 

segments (3.15 total 

miles)

- Crooked Creek 

(above fish 

barrier – 1.59 

miles) tentative 

management 

class would be 

Wild

- Crooked Creek 

(below fish 

barrier – 1.56 

miles) tentative 

management 

class would be 

Scenic