| Business | Phone |
| Air Pollution Control Div 4300 Cherry Creek South Dr, Denver 80246 | (303) 692-3100 |
| Environment Office 4300 Cherry Creek South Dr, Denver 80246 | (303) 692-3099 |
| Hazardous Materials & Waste 4300 Cherry Creek South Dr, Denver 80246 | (303) 692-3300 |
| Water Quality Control Div 4300 Cherry Creek South Dr, Denver 80246 | (303) 692-3500 |
| Water Resources Div 1313 Sherman St # 818, Denver 80203 | (303) 866-3581 |