HomeMy WebLinkAboutOWTS Installation Observations 03.26.202133 Four Wheel Drive Road
Carbondale, CO 81623
970.309.5259
carla.ostberg@gmail.com
March 26, 2021 Project No. C1546
Larry and Judy Maudlin
c/o Brad Jordan
bradjordanarchitect@gmail.com
Onsite Wastewater Treatment System (OWTS) Installation Observations
TBD Rapids View Lane
Lot 5, Rapids on the Colorado
Garfield County, Colorado
Permit Number SEPT-08-20-6426
Larry and Judy,
Photos of the onsite wastewater treatment system (OWTS) installation were provided to us by Ted White
with Garfield County Environmental Health Department and you, the property owner, on November 19,
2020. We were unable to conduct a site visit on that date due to Covid. You, the property owner,
installed the system.
The OWTS design is based on 4-bedrooms. An average daily wastewater flow of 525 GPD was
used.
The 4-inch diameter sewer line exiting the residence has a double-sweep clean out and a minimum 2%
grade to the septic tank. An additional clean out was added in front of the septic tank. This clean out
may be used for occasional dumping of Recreational Vehicle (RV) wastewater. No chemicals should be
introduced to the OWTS through this process. All sewer pipes used in this installation were Schedule 40.
The system installation included a 1500-gallon, two-compartment Valley Precast concrete septic tank
with an effluent filter on the outlet tee. This filter must be cleaned annually, or as needed. Risers
must bring the manhole lids to grade for access. If more than one riser is added to the septic tank, an
extension handle must be installed on the effluent filter.
Effluent will gravity flow to a distribution box, and then to four gravelless chamber trenches. The
distribution box was accessible from grade and had flow equalizers installed on each outlet pipe in the
distribution box to assure equal flow to each trench.
Each trench consisted of 11 ‘ARC’ ADS chambers for a total of 44 chambers and 660 square feet of
infiltrative area. There must was least 4-feet of undisturbed soil between each trench. The trenches
were least 10-feet from the property line. Inspection ports were installed at the beginning and end of
each trench. Ports may be cut to grade and placed in sprinkler boxes for access.
An as-built drawing was provided by you and is enclosed with this packet. Measurements are
provided for reference.
The OWTS was generally installed according to specifications. This observation is not a guarantee of
workmanship and/or parts and materials. CBO Inc. should be notified if changes are made to the OWTS
in the future. Any additional OWTS construction must be according to the county regulations.
LIMITS: Observations are limited to components that are visible at the time of the inspection. The installer must
have documented and demonstrated knowledge of the requirements and regulations of the county in
which they are working. The quality of the installation is dependent of the expertise of the installer, soil
type, and weather conditions.
Please call with questions.
Sincerely,
CBO Inc.
Carla Ostberg, MPH, REHS
View of septic tank
Effluent filter (add extension handle if riser is more than 1-foot)
RV clean out (occasional use only, no chemicals)
ARC chambers
1500 gallon septic tank
Chamber trenches
Sewer line from tank (Sch 40) Sewer line to Dbox
Distribution box
Clean out near house
Trenches and inspection port
Distribution box
832‐R‐13‐002