St. Mathew Island Area, Alaska

Survey Area AK701• Alaska

The dominant drainage class is Well drained and the dominant hydrologic group is D (very slow infiltration, high runoff). The most common soil order is Gelisols — permafrost soils found in very cold climates. This report summarizes the major soil map units across the survey area to help you understand what to expect when buying, building, or gardening in St. Mathew Island Area, Alaska. Search your address to find the exact soil composition, drainage, and series details at your specific location.

Soil Map Unit	Acres	Drainage	Hydro Group	Dwellings	Septic
Northern Bering Sea Islands-NorthMaritime Upland-Rounded Mountains	49K	Well drained	D	Very limited	Very limited
Northern Bering Sea Islands-Maritime Upland-Plains	20K	Very poorly drained	D	Very limited	Very limited
Northern Bering Sea Islands-Maritime Lowland-Coastal Plains	12K	Very poorly drained	B/D	Very limited	Very limited
Northern Bering Sea Islands-Maritime Water, Saline	2K			Not limited	Not limited

Soil Orders in This Area

The USDA classifies every soil into one of 12 soil orders. Here are the dominant orders found in this survey area.

Gelisols

Permafrost soils. Extremely challenging for construction and septic. Found almost exclusively in Alaska.

Inceptisols

Young but developing soils found in mountains and river terraces. Variable properties — check drainage and bedrock depth.

Entisols

Young soils with little development — found on floodplains, dunes, and steep slopes. Properties vary widely by setting.

Histosols

Organic peat and muck soils formed in wetlands. Very poor for building (compressible) and septic. Often in regulated wetlands.

What This Means

Building & Foundations

About 97% of soils are rated "very limited" for dwellings with basements. Specific challenges include steep slopes, poor drainage in some areas, flood-prone areas. A geotechnical assessment is recommended before building.

Septic Systems

About 97% of soils are rated "very limited" for septic absorption fields. Despite good drainage overall, limitations may stem from shallow bedrock, steep slopes, or seasonal conditions. Engineered or alternative systems are frequently required. Always get a professional perc test before purchasing land that needs septic.

Gardening & Agriculture

Drainage is generally favorable for gardening. Adding compost and mulch will improve fertility and water retention. Test your soil's pH before planting — most vegetables prefer 6.0-7.0.