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Home My WebLink AboutOWTS Design 02.10.2026i 129 CAINS LANE CARBONDALE, CO 81 623 970.309.5259 -" GARLA.OSTBERG@GMAfL.COM �5i•a'"CI[:' CCl�f3i'L'i`r\C. February 10, 2026 Project No. C2017 James Passchier iames.levelbuildco@qmaii.com Onsite Wastewater Treatment System Design 5-Bedroom Residence + 2-Bedroom Shop/ADU 422 Rose Lane Garfield County, Colorado James, CBO Inc. performed a subsurface investigation and completed an onsite wastewater treatment system (OWTS) design for the subject residence. The 2.61-acre property is located outside of Carbondale, in an area where OWTSs and wells are necessary. Legal Description: Section: 35 Township: 7 Range: 88 TR IN LOT 9 Parcel ID: 2393-352-00-011 SITE CONDITIONS The property is currently developed with a manufactured home and out -buildings. All existing structures will be removed and the OWTS serving the manufactured home will be abandoned. A 5-bedroom residence and detached Shop with a 2-bedroom accessory dwelling unit (ADU) are proposed. The residences will be served by a private well on the property. The well is located on the eastern portion of the property. The well is located greater than 50-feet from the proposed septic tank and greater than 100-feet from the proposed soil treatment area (STA). There are several ditches on the property. The ditch that runs along the eastern property boundary will be placed in a culvert and no OWTS component will come within 10-feet of the ditch. The ditch that runs along the southern property boundary will be abandoned. No open (not in a culvert, pipe, or lined) portion of any ditch will come within 50-feet of any OWTS component. The proposed STA location is relatively flat, sloping slightly to the north. The proposed mounded STA will parallel the eastern property boundary. The proposed area is vegetated with native grasses. There should be no traffic or staging of material over the future STA site to avoid compaction of soils prior to construction of the STA. SUBSURFACE The subsurface was investigated by Kumar and Associates, Project No. 25-7-622, Subsoil Study for Foundation Design, and is documented in -a report dated December 23, 2025 (enclosed). Four test pits (Pits) were excavated on the eastern portion of the property to approximately 3.5-feet below native grade. Groundwater was encountered in every Pit, with depth to groundwater as shallow as 1.0-foot below native grade in Pit 3. Page 2 Given the presence of groundwater in the native alluvial (gravel and cobbles), we do not feel that additional soil evaluation is necessary. Soil Type R-0 will be used to size the STA. We are proposing a pressure - dosed, mounded, unlined sand filter. Vegetation will be scraped to no more than 1.0-foot below native grade and 3-feet of sand filter material (Secondary Sand) used to create the mound. A long term acceptance rate (LTAR) of 0.8 gallons per square foot will be used to design the STA. DESIGN SPECIFICATIONS The existing OWTS serving the manufactured home will be properly abandoned or removed. Design Calculations: Main House = 75 GPD x 2 people/bedroom x 3 Bedrooms + 150 GPD (4th and 5th Bedrooms) = 600 GPD Shop / ADU = 75 GPD x 2 people/bedroom x 2 Bedrooms = 300 GPD Average Design Flow = 600 GPD + 300 GPD = 900 GPD LTAR = 0.8 GPD/SF 900 GPD / 0.8 GPD/SF = 1125 SF The OWTS design is based on 5-bedrooms in the Main House and 2-bedrooms in the Shop/ADU. An average daily wastewater flow of 900 GPD will be used. For the purposes of this OWTS design, Benchmark Elevation at grade 6171.5' has been established as 100' (Finished Floor Main House). The finished floor elevation of the Shop/ADU is 6172.5'. CBO Inc. should be notified of any discrepancies or problems with grade elevations of proposed components during installation of the OWTS. OWTS Component Primary Tank Inlet Invert Minimum Elevation Approximate horizontal distance 53' from Main House / min. 2% fall / min. 13.25" fall Approximate horizontal distance 70' from Shop/ ADU / min. 2% fall / min. 17.5" fall Automatic Distributing Valve Approximate horizontal distance 28' / min. 1 % rise / min. 3.5" rise Infiltrative Surface Approximate horizontal distance 11' / min. 1% fall to STA / min. 1.375" fall *Elevations are based upon standard OWTS installation practices. Component elevations may change during installation due to site conditions. Minimum grade refers to piping between components. The 4-inch SDR-35 sewer lines exiting the residences must have a double -sweep clean out and a minimum 2% grade to the septic tank. The sewer line should exit the residences to allow fall while keeping the septic tank installation as shallow as possible due to the presence of high groundwater. Sewer lines should be covered with BlueBoard insulation where depth is less than 18-inches. The system installation will include a 2000-gallon, three -compartment Valley Precast concrete septic tank with an Orenco@ Biotube Pump Vault and an Orenco® PF3005 pump in the third compartment of the septic tank. Anchoring the septic tank with Deadmen will be necessary due to the high seasonal groundwater table. Please follow manufacturer recommendations based on the height of the water table and cover over the septic tank. The floats should be set to dose approximately 70 gallons each pump cycle, allowing approximately 3 gallons of drain back. The control panel for the pump must be located within line of sight of the septic tank. An electrician will be responsible for wiring the pumping system and the contractor will be responsible for connecting the plumbing. We recommend Valley Precast out of Buena Vista be contracted for start-up. This office must be contacted to test the system to verify its functioning and to perform a squirt test prior to use. Page 3 _Pump Table Dose Range Dose Setting Float Separation Pump Criteria Max = 228 gal. (900 GPD x 25°/] Min. 49 gal. (11.5 gal x 4) + 3 gal + 3 gal drain back) drain back 70 gallons/dose 3 gallons drain back (28' / 1.5" diameter numn line 2000 gallon, three -compartment Valley Precast concrete septic tank with pumping system in third compartment (total volume 2500- gallons) 21.7 gallons per minute (GPM) CONSULT VALLEY PRECAST FOR RECOMMENDED FLOAT SETTINGS 17.3 feet total dynamic head (TDH) Effluent will be pressure dosed through a 1.5-inch diameter pump line to a mounded, unlined sand filter. The sand filter will be divided into two beds, each 12' x 47' with some room between beds for plumbing. The excavation for the sand filter may not extend greater than 1.0-foot below native grade. A minimum of 3-feet of sand filter material will be installed in the over -excavated footprint. Sand filter material must be clean, coarse sand, all passing a screen having four meshes to the inch. The sand must have an effective size between 0.15 and 0.60 mm. The uniformity coefficient must be 7.0 or less. Material meeting ASTM 33, for concrete sand, with three percent or less fines passing 200 mesh sieve may be used. A gradation of the sand media must be provided. Effluent will be pumped through a 1.5-inch diameter pump line from the pump chamber to an Orencoo automatic distributing valve (ADV), model 6404. This pump line must have a minimum 1 % grade for proper drain back into the tank after each pump cycle. The ADV must be placed at a high point of each zone in an insulated riser with access from grade. Screened rock must be placed below the ADV to support the ADV and to assure the clear pipes exiting the ADV remain visible for future inspection and maintenance. Level, 1.5-inch diameter manifolds will connect two laterals on each bed (see W3.0/1 Mounded Sand Filter Plan). Laterals must be 1.5-inches in diameter with 5/32-inch diameter orifices facing down, spaced 3.0- feet on center, installed on the 39-inch wide GeoMatTM sheets. Proprietary gray filter fabric will cover the laterals. Four 39" wide GeoMatTM must be placed on the 12-foot wide bed, and will over -lap slightly. All material associated with the GeoMatTM installation must be proprietary products associated with the GeoMatTM' including orifice shields. Manufacturer instructions must be followed regarding installation of the GeoMatTM. Each 1.5-inch diameter lateral must end in a sweeping ell facing up with a ball valve for flushing. The same size orifice should be drilled in the screw on caps of the flushing valves so a squirt test can be performed. Laterals must be covered by the gray GeomatTM soil separation fabric and at least 1-foot of topsoil or other suitable soil able to support vegetative growth. There shall be no cobble -sized (2.5") or greater rock in final cover over the GeoMatTM. Inspection ports must be placed into the sand filter material on each corner of the beds. The mound must have a minimum 3:1 slope (horizontal:vertical); therefore, the basal area will extend approximately 12-feet beyond the sand filter on all sides (with a mound height of approximately 4.0-feet above native grade). Soils in the sloped perimeter areas of the mound must be well draining and able to support vegetative growth. This soil must be approved by this office prior to installation. The mound must be crowned in a manner to promote drainage off the STA. Page 4 COMPONENT SPECIFICATIONS The component manufacturers are typical of applications used by contractors and engineers in this area. CBO Inc. must approve alternative components prior to installation of the OWTS. Requests must be submitted, in writing, to our office for approval prior to installation. Component technical data sheets are available upon request. COMPONERN—T-1 MANUFACTURER MODEL NO. COMMENTS Septic Tank Valley Precast Item # 2000T-3CP-HH 2O00-gallon, 3- compartment concrete septic tank (2500 gallons total volume 30 gpm pump Pump Orenco@) PF300511 '/z HP 120 Volt Biotube ProPak Pump Package Tank Risers and Lids Orenco@ Orenco@ BPP50DD Vault, Filter demand dose Double -walled PVC Risers and Lids (24" diameter) ADV Orenco@ V6404A 1.5" Inlet and Outlets ADV Riser and Lid Orenco@ Double -walled PVC Risers and Lids 30' diameter Flushing Assembly Orenco@ 1.5" diameter (2) 45" or 900 long sweep only 8 total GeoMatTM GeoMatrix Systems, LLC 376' GeoMatTM (39") and 112 Orifice Shields Construction must be according to the jurisdiction's adopted On -Site Wastewater Treatment System Regulations, the OWTS Permit, and this design. PERMIT APPLICATION INSTRUCTIONS An OWTS Permit Application must be submitted to Garfield County Environmental Health Department. htts://www. arfeld-coup .com/environmental-heaIth/files cco/sites/l6/OV TS-A lication-Com lete- Packet-Dec.-2019. df. If the OWTS Permit Application will be submitted with a Building Permit Application, it should be submitted directly to Garfield County Building Department. All questions regarding permit submission can be directed to Garfield County Environmental Health Department, 970-945-6614 x8150. VALIDITY PERIOD OF DESIGN DOCUMENTS This design is valid for submission of an application for permitting for two (2) years from the date of the design packet or upon a change in the county OWTS Regulation that could impact compliance with code requirements. Continued use beyond this period or following a change in the regulation is not recommended without review and update of design documents. INSTALLATION CONTRACTOR CBO Inc. expects that the installer be experienced and qualified to perform the scope of work outlined in this design. The installer must review this design thoroughly and coordinate with our office in advance of installation. Any additional conditions in this design or county permit must be completed and documented prior to final approval of the OWTS installation. Communication between the installer and this office is expected throughout the installation. Page 5 INSTALLATION OBSERVATIONS CBO Inc. must view the OWTS during construction. The OWTS observation should be performed before backfill, after placement of OWTS components. Septic tanks, distribution devices, pumps, dosing siphons, and other plumbing, as applicable, must also be observed. CBO Inc. should be notified 48 hours in advance to observe the installation. In an effort to improve the accuracy of the record drawing, we request that the installer provide a sketch of the installation, including path of the sewer lines, water line installation (if applicable), septic tank location, STA location, and measurements from building corners or another fixed objects on the property. This sketch is most easily provided on Sheet W2.0 of the OWTS Design Packet. Photographs of the installation and final cover are also requested to supplement our installation documentation. REVEGETATION REQUIREMENTS An adequate layer of good quality topsoil capable of supporting revegetation shall be placed over the entire disturbed area of the OWTS installation. A mixture of native grass seed that has good soil stabilizing characteristics (but without taproots), provides a maximum transpiration rate, and competes well with successional species. No trees or shrubs, or any vegetation requiring regular irrigation shall be placed over the STA. Until vegetation is reestablished, erosion and sediment control measures shall be implemented and maintained on site. The owner of the OWTS shall be responsible for maintaining proper vegetation cover. OPERATION INFORMATION AND MAINTENANCE The property owner shall be responsible for the operation and maintenance of each OWTS servicing the property. The property owner is responsible for maintaining service contracts for manufactured units, alternating STAs, and any other components needing maintenance. Geo-fabrics or plastics should not be used over the STA. No heavy equipment, machinery, or materials should be placed on the backfilled STA. Machines with tracks (not wheels) should be used during construction of the STA for better weight distribution. Livestock should not graze on the STA. Plumbing fixtures should be checked to ensure that no additional water is being discharged to OWTS. For example, a running toilet or leaky faucet can discharge hundreds of gallons of water a day and harm a STA. If an effluent filter or screen has been installed in the OWTS, we recommend this filter or screen be cleaned annually, or as needed. If the OWTS consists of a pressurized pump system, we recommend the laterals be flushed annually, or as needed. The homeowner should pump the septic tank every two years, or as needed gauged by measurement of solids in the tank. Garbage disposal use should be minimized, and non -biodegradable materials should not be placed into the OWTS. Grease should not be placed in household drains. Loading from a water softener should not be discharged into the OWTS. No hazardous wastes should be directed into the OWTS. Mechanical room drains should not discharge into the OWTS. The OWTS is engineered for domestic waste only. ADDITIONAL CONSTRUCTION NOTES If design includes a pump, weep holes must be installed to allow pump lines to drain to minimize risk of freezing. The pump shall have an audible and visual alarm notification in the event of excessively high- water conditions and shall be connected to a control breaker separate from the high-water alarm breaker and from any other control system circuits. The pump system shall have a switch so the pump can be manually operated. Page 6 Excavation equipment must not drive in the excavation of the STA due to the potential to compact soil. Extensions should be placed on all septic tank components to allow access to them from existing grade. Backfill over the STA must be uniform and granular with no material greater than minus 3-inch. LIMITS: The design is based on information submitted. If soil conditions encountered are different from conditions described in this report, CBO Inc. should be notified. All OWTS construction must be according to the county regulations. Requirements not specified in this report must follow applicable county regulations. The contractor should have documented and demonstrated knowledge of the requirements and regulations of the county in which they are working. Licensing of Systems Contractors may be required by county regulation. Please call with questions. Sincerely, CBO Inc. (!a,k (a, Oaf &As Carla Ostberg, MPH, REHS Reviewed By: Kachayla Renee Schroeder, P.E. Colorado License No. 6144.0 Mack. C o Sji1; Pump Selection for a Pressurized System - Single Family Residence Project 422 Rose Lane Parameters Discharge Assembly Size 1 25 inches Transport Length Before Valve 28 feet Transport Pipe Class 40 Transport Line Size 1.50 inches Distributing Valve Model 6404 Transport Length After Valve 11 feet Transport Pipe Class 40 Transport Pipe Size 1 50 inches Max Elevation Lift 3 feet Manifold Length 8 feet Manifold Pipe Class 40 Manifold Pipe Size 1.50 inches Number of Laterals per Cell 8 Lateral Length 45 feet Lateral Pipe Class 40 Lateral Pipe Size 1.50 inches Orifice Size 5/32 inches Orifice Spacing 3 feet Residual Head 5 feet Flow Meter None Inches 'Add -on' Friction Losses 0 feet Calculations Minimum Flow Rate per Orifice 0.68 gpm Number of Orifices per Zone 32 Total Flow Rate per Zone 21.7 gpm Number of Laterals per Zone 2 % Flow Differential 1 st/Last Orifice 1.2 % Transport Velocity Before Valve 3.4 fps Transport Velocity After Valve 3A fps Frictional Head Losses Loss through Discharge 3.3 feet Loss in Transport Before Valve 0.8 feet Loss through Valve 4.7 feet Loss in Transport after Valve 0.3 feet Loss in Manifold 0A feet Loss in Laterals 0.1 feet Loss through Flowmeter 0.0 feet 'Add -on' Friction Losses 0.0 feet Pipe Volumes Vol of Transport Line Before Valve 2.9 gals Vol of Transport Line After Valve 1.2 gals Vol of Manifold 0.8 gals Vol of Laterals per Zone 9.5 gals Total Vol Before Valve 2.9 gals Total Vol After Valve 11.5 gals :quirements 21.7 gpm 17.3 feet Orenco 300 Mill 200 d d LL 2 F- 50 5 10 15 20 25 30 35 40 Net Discharge (gpm) PumpData PF3005 High Head Effluent Pump 30 GPM, 1/2HP 115/230V 10 60Hz, 200V 30 60Hz PF3007 High Head Effluent Pump 30 GPM, 3/4HP 230V 10 60Hz, 200/460V 30 60Hz PF3010 High Head Effluent Pump 30 GPM, 1HP 230V 10 60Hz, 200/460V 30 60Hz PF3015 High Head Effluent Pump 30 GPM, 1-1/2HP 230V 10 60Hz, 200/230/460V 30 60Hz System Curve: Pump Curve: Pump Optimal Range: Operating Point: 0 Q Design Point: al 00 .. o CTI W 0 00 N N CT 00 TI CD (D O O:3 O O O G G fA .O•e O O G � y y i O O D N O A CQ CD CD C N 7 a0 3 S N N ti U G � G tr y O CD N y O O Z3 S _3 4 m y 3 3 m 3 O O O O 3 G N C y � o m c m m � l Ca m � ° a m o 0 � � l N O' N O W N O Z, G rn �u rn o 7 N Cr: 0 gPubiic.net Garfield County, CO Account Number R011480 Parcel Number 239335200011 Acres 3 Land SgFt 0 Tax Area 011 Mill Levy 76.1560 Date created:1/20/2026 Last Data Uploaded:1/20/2026 2:09:30 AM Developed byfiA S C H N E I D E R GEDSPATIAL Physical Address 422 ROSE LN CARBONDALE 81623 Owner Address SCHAUSTER, ERMA J 422 ROSE LANE CARBONDALE CO 81623 Overview Legend F] Parcels Roads Parcel/Account Numbers Owner Name Lakes & Rivers .... County Boundary Line Total Actual Value $0 Last 2 Sales Date Price n/a $ n/a $ 2/10/26, 9:50 AM gPublic - Garfield County, CO - Properly Record Card: M001140 Garfield County, CO Summary Account Parcel Property Address Legal Description Acres Land SgFt Tax Area Mill Levy Subdivision Map M001140 422 ROSE LN, CARBONDALE, CO 81623 MBL HOME TITLE: 015109620 SERIAL: 72272104S2298A YEAR: 1966 MAKE: CHAM SPACE: 0 2393-352-00-011, CHICKASHA PATRICH 0 0 11 76.1560 Owner PAS$C H I ER. JA MES D & CA_ RLY M 422 ROSE LANE CARBONDALE CO 81623 Buildings Building# Units Building Type Abstract Codes / (Property Type) Architectural Style Stories Frame Actual Year Built Gross Living Area Total Heated SgFt Bedrooms Baths Heating Fuel Heating Type Air Conditioning Roof Type Roof Cover Actual Values Tax Year Actual Value Assessed Values Tax Year Non School Assessed Value 1 1 UPVALLEY PRE HUD MOBILE HOME MANUFACTURED HOUSING - IMPRVMT-1235 (RESIDENTIAL PROPERTY) 20 WIDE 1 WOOD 1966 969 969 3 1.5 NAT GAS FORCED AIR ROOFTOP FLAT METAL 2025 2024 2023 2022 2021 $112,930.00 $92,950.00 $92,950.00 $62,940.00 $62,940.00 2025 2024 2023 2022 2021 $7,060.00 n/a n/a n/a n/a School Assessed Value $7,960.00 n/a n/a n/a n/a Pre 2025 Assessed Value n/a $6,230.00 $6,230.00 $4,370.00 $4,500.00 `House Bill 24B-1001 established a separate assessment rate for school district residential properties, effective for the 2025 tax year and beyond. Click here for Assessor FAQs Mill Levies Tax Year 2025 2024 2023 2022 2021 Non School District Levy 34.701 n/a n/a n/a n/a School District Levy 41.455 n/a n/a n/a n/a Total Levy 76.156 74.414 72.518 81.029 79.776 https://gpublic.schneidercorp.com/Application.aspx?ApplD=1038&LayerlD=22381&PageTypelD=4&PagelD=9447&Q=391891384&KeyValue=M001140 1/3 2/10/26, 9:50 AM gPublic - Garfield County, CO - Property Record Card: M001140 Tax History Tax Year 2025 2024 2023 2022 2021 Non School Taxes $245.00 n/a n/a n/a n/a School Taxes $330.00 n/a n/a n/a n/a Taxes Billed $575.00 $463.60 $451.80 $354.08 $359.00 Clack he re to view the sag information far this Bartel on the Garfield Count V. Tre=surer s %vebmle. Transfers Sale Date Deed Type Reception Number Book - Page Sale Price 1/12/2026 Manufactured Home Verification of Applic 1014989 So. 1/12/2026 CONVEYANCE _ $0 9/25/2025 LETTERS 4/1/2014 DEATH CERTIFICATE Property Related Public Documents Click hers to vicw PropertyPropcirty Retated Public Dom m rt Photos Sketches 1014688 $0 850805 $0 https://gpublic.schneidercorp.com/Application.aspx?ApplD=1038&LayerID=22381&PageTypelD=4&PagelD=9447&Q=391891384&KeyValue=MO01140 2/3 2/10/26, 9:50 AM qPublic - Garfield County, CO - Property Record Card: M001 140 SWt;b by Apm N Wr-k-; I 12 0' I 28-(Y 06 se.a Fr 4 ONE STORY 12--ff Co ai DBLE WIDE MFG HOME 0� 969-0 FTC 51.01 No data available for the following modules: Land. sorsoffi, i e :j-,! Gaefie I d" Co-Un,'� As, 5e.s pas,,:b1c. N"ov.,arrW.,,tics, exp:;,(,,,sed or implied z4re p-Ovided ',). the data hercin. its Use or Datz) i5 subje-rt !U<) ccnst,-,t rhange ard its accur,,xy and 9itr--Privacy±o--rrcy I 9-D--PR Lya—cy-Lo—t� List Data Upload. 2110/2026.11-jZ&A 3 AM contaci Us by SCH NEI DER hftps://qpublic.schneidereorp.com/Application.aspx?ApplD=l 038&LayerlD=22381 &PageTypelD=4&PagelD=9447&Q=391891384&KeyValue=M001140 3/3