South Dakota Department of Transportation
Wyoming Department of Transportation

United States Army Corp of Engineers
United States Department of Interior

• Bureau of Indian Affairs
• National Park Service

United States Department of Energy
Burlington Northern Railroad
Dakota Minnesota Eastern Railroad
MW Kellogg-Brown & Root Companies

Shell Mining

AMAX Coal Company
Atlantic Richfield
Cypress Coal Company
Peabody Coal Company
American Colloid Company

Midwest Development Corporation
Chen & Associates Engineers & Scientists
HKM & Associates
Brosz Engineering

Walmart
CC Hutchinson & Sons
Johnson Bros. Company