5 Colo. Code Regs. § 1002-22.13
Notwithstanding the definition of domestic wastewater treatment works (treatment works) at subsection 22.2 of this regulation, once an owner has received site location approval, the owner may initiate work in preparation for construction, (e.g., site clearing, site dewatering and access roads) as long as such work is completed by the owner's own forces or is completed under a contract that does not include any elements of the construction of the treatment works including, but not limited to site excavation, construction of pipe galleries, and procurement or installation of equipment. Facilities generating reclaimed domestic wastewater are domestic wastewater treatment works and are required to complete the design review process. The PDR and the final design documents must be stamped and signed by the applicant's professional engineer, registered to practice in the State of Colorado.
For a new, modified, or expanded domestic wastewater treatment plant, the applicant must submit the Process Design Report (PDR), stamped and signed by the applicant's professional engineer who must be registered to practice in the State of Colorado, a completed PDR checklist, and any requests for site specific deviation from the CDPHE design criteria for domestic wastewater treatment works. Following approval of the PDR by the Division, the applicant and their engineer must submit a self-certification of the final design documents. At the Division's discretion, or when funding requires, the applicant may be required to complete the full design review process which would require the Division to approve final plans and specifications in lieu of the self-certification by the application and their engineer. When the final design documents (plans and specifications) are complete, the professional engineer for the applicant that prepared such plans shall submit a stamped, dated, and signed certification on a form provided by the Division affirming that the final design is consistent with the approved site application, the PDR approval letter, and the most recent version of the Division's design criteria for domestic wastewater treatment works, noting any approved site-specific deviations from the Division's design criteria. The proposed project cannot move forward into the construction stage without site location approval by the Division, approval of the PDR, and Division acceptance of the self-certification request letter or written approval by the Division when final plans and specifications are required by the Division in lieu of a self-certification by the applicant and engineer.
If the Division discovers discrepancies between the facilities as described in the Basis of Design or PDR approval letter and those finally constructed, the applicant will either make modifications to resolve the inconsistency to the Division's satisfaction or the approval of the design will be null and void. Similarly, if the Division discovers discrepancies between the facilities or capacities described in the interceptor certification or site location approval and those finally constructed, the applicant will either agree to make modifications to resolve the inconsistency to the Division's satisfaction or the approval of the site location will be null and void.
In some cases, the design of the domestic wastewater treatment works can impact the cost and funding of the preferred option specified in the site location application. In such cases the applicant is encouraged to consult with the Division regarding the specific circumstance and identify critical design issues during the site application review to avoid obtaining site location approval for an option that will not be able to obtain design approval.
5 CCR 1002-22.13