Region
Colorado
7
Wyoming
7
Arizona
4
Borneo Region
2
California
2
Fremont County
2
Uinta Basin (Utah and Colo.)
2
Alaska
1
Arkansas
1
Douglas Creek area
1
Grand Canyon
1
Grand Canyon (Ariz.)
1
Inyo County
1
Katalla Region
1
Nevada
1
Nye County
1
Piceance Creek Basin
1
Powder River Watershed (Wyo. and Mont.)
1
Snake River Region
1
Sweetwater County
1
Teton County
1