| Business | Phone |
| Air Specialist Inc 1148 1st Ave N # 203, Billings 59101 | (406) 259-2970 |
| Wetlands Inc 2744 Gregory Dr N, Billings 59102 | (406) 655-7926 |
| Yellowstone Soil Treatment 4748 Rimrock Rd, Billings 59106 | (406) 655-4499 |
| Timberline Resources Inc 2815 Montana Ave, Billings 59101 | (406) 294-9496 |
| Cre Inc 2530 Woody Dr, Billings 59102 | (406) 656-1770 |
| Environmental Consulting Svc 451 Freedom Ave, Billings 59105 | (406) 254-1741 |
| Environmental Contractors 2701 Overland Ave, Billings 59102 | (406) 652-6337 |
| Indoor Environmental Llc 1119 Maggie Ln, Billings 59101 | (406) 256-9192 |