Under what conditions must an on-site wastewater treatment system (OWTS) be designed by a Colorado Licensed Professional Engineer?

A Colorado Licensed Professional Engineer must design a system if any of the following occur: (a) the following soil types are identified within 4 feet below the depth of the proposed soil treatment area (STA): 0, 3A, 4, 4A, 5, R-O, R-1, R-2; treatment levels TL2, TL2N, TL3, and TL3N as specified in tables 10 and 11 of Regulation O-17 (b) groundwater, bedrock, or other limiting layer is present within 4 feet below the depth of the proposed STA, (c) the ground slope at the area of the proposed STA is greater than 20%, or (d) the proposed system is a commercial system, (e) the proposed system utilizes pressure distribution.

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1. How do I get a permit to build a new, or repair an on-site wastewater treatment system (OWTS)?
2. Under what conditions must an on-site wastewater treatment system (OWTS) be designed by a Colorado Licensed Professional Engineer?
3. How do I get a Use Permit?
4. Who can do Use Permit inspections?
5. I am selling my property and need to get my waste water system certified. What should I do?
6. What is the minimum lot size for an on-site wastewater treatment system (OWTS)?
7. How often do I need to pump my septic tank?
8. Will I be able to irrigate or have horses where my Soil Treatment Area (STA) is located?
9. Can I install a bathroom in a garage, barn, etc., and connect it to my existing on-site wastewater treatment system (OWTS)?
10. I am unsure where my onsite waste water treatment system (OWTS) is located. Do you have records of my system?
11. I accidentally damaged some components of my septic system. Who should I call to inspect and repair the damage? Do I need a permit?