Garfield County, MT Contractor directory
Excavation contractors in Garfield County, MT
1 verified excavating and site work contractor serving Garfield County.
County excavation guide
Ground conditions and project requirements in Garfield County
Use this local research to understand soil, seasonal constraints, permits, and jobsite logistics before choosing a contractor.
Skip to 1 contractorSoil Regime ProfileEPA Ecoregion 42, 43, 41 (Northwestern Glaciated Plains, Northwestern Great Plains, Northern Rockies)
Montana Glaciated Plains, Shale Breaks & Northern Rockies
Dominant Soil Order: Mollisols / Inceptisols / Aridisols
Parent Material: Glacial Till and Tertiary Sediments over Pierre and Bearpaw Shale; Smectite Shale Badlands; Precambrian Belt Series and Volcanics in the Rockies
Montana is the shale-and-rock end of the northern plains. The glaciated east (Great Falls, Havre, Glasgow) sits on glacial till and Tertiary sediments over the Pierre and Bearpaw shales, and the bentonitic shales bring the northern plains' worst ground: smectite clay that swells and shears, landslide-prone bluffs along the Missouri and Milk rivers, and shrink-swell behavior severe enough to shape every rural foundation. Saline seeps (discharge wet spots that kill crops) mark the shale uplands, and the state's alkaline soils complicate septic design. Digging in the till plains is easy where the shale is deep; shallow shale bedrock appears in the breaks. West of the Continental Divide the Northern Rockies take over: crystalline Belt Series rock, glacial valley fill, steep slopes (30-80 percent in the mountain counties), and the only serious blasting in the state. Frost runs 42-60 inches, the deepest in the lower 48. Hydric soils are rare in the arid east, common in the wet mountain valleys.
Geographic Footprint:Montana's counties (Billings, Missoula, Great Falls, Bozeman) split between shale-badlands plains east of the Rockies and mountain-valley glacial fill west: Pierre shale movement and saline seeps in the east, rock work and steep valley walls in the west. The 42-60 inch frost line is the deepest in the lower 48.
Geotechnical Baseline
Physical Ground Conditions & Soil Properties
Shallow Bedrock (<50 in)
39.1%of county land area
High likelihood of bedrock refusal; hammer / ripper required for deep utilities.
High Shrink-Swell Clay
9.6%expansive soil
Low volumetric expansion risk in native subgrade.
Median Water Table Depth
48inches from surface
Deep water table; dry trenching conditions under normal weather.
Hydric / Wetland Soils
0.1%hydric coverage
Indicates poor natural drainage and potential jurisdictional wetland pockets.
Steep Terrain (Slope >15%)
34.7%of terrain
Mountain/hilly terrain; terracing, benching, and tracked haulers frequent.
Septic Severe Limitations
70.2%severe rate
High rate of conventional drainfield limitations; engineered or drip systems often required.
Dominant Soil Textures:Silt loamLoamFine sandy loam
Surface Stones / Boulders: 26.8% coverage
Compliance & Permitting
Earthwork Regulations & Permit Thresholds
Stormwater & Erosion Control
Montana DEQ MPDES Storm Water Discharges Associated with Construction Activity General Permit MTR100000 (effective Jan 1, 2023 through Dec 31, 2027). Applies to construction activities disturbing at least one acre where a discharge to state surface water can occur (excludes Indian country).
Administers NPDES stormwater discharge coverage for land-disturbing construction activities.
State Threshold:1.00 Acre
Local Threshold:Follows state
Onsite Wastewater & Utilities
Garfield County Health Department (Sanitarian)
Jurisdiction over septic tank permits, soil evaluation perk tests, and drainfield sizing.
Housing on Septic:55.0%
Soil Evaluation:Site evaluation by a county-qualified site evaluator, registered sanitarian or PE; at least 4 ft from natural ground to limiting layer unless waived
811 One-Call Requirements
Montana 811 (Utilities Underground Location Center)
Mandatory notice window: 48 hours prior to mechanized earthwork (excluding weekends and legal holidays).
Licensing & Clearing Permits
Weather & Ecology
Seasonal Constraints & Clearing Windows
Frozen Ground Days
90days / year
Typical days with sub-freezing soil conditions affecting digging.
Wet Season Months
May, June, July
Peak precipitation window requiring sediment traps and soil aeration.
Supply Chain & Hazards
Logistics, Aggregate Sources & Geohazards
Aggregate & Material Supply
Belzer Pit
Nearest active quarry: 68.7 miles haul distance.(0 active crushed stone/sand operations within 50 miles).
Flood & Hazard Overlay
NWI Wetlands:11.6%jurisdictional coverage
Karst Terrain & Sinkhole Risk: Low
0.0% of county underlain by soluble carbonate rock formations.
HUC8 Primary Watersheds:Lower Milk, Fort Peck Reservoir, Big Dry, Little Dry, Middle Musselshell, Lower Musselshell
Public conservation land: -14.7% (USGS PAD-US).
Area-specific FAQ
Do I need to call before digging in Garfield County?
Yes. You should contact Montana 811 at least 2 working days before any digging so underground lines can be marked.
How deep do footings need to be in Montana?
In Montana, footings typically need to extend below the frost line, which is around 60 inches here. A local contractor will confirm the code requirement for your site.
Verified local listings
Excavation contractors serving Garfield County
1 verified listing