HomeMy WebLinkAboutOWTS Design129 Cains Lane
Carbondale, CO 81623
970.309.5259
carla.ostberg@gmail.com
January 30, 2022 Project No. C1691
Michael and Tammy Koski
c/o Jacob Koski
jacobkoski@gmail.com
Onsite Wastewater Treatment System Septic Tank Replacement Design
5-Bedroom Residence
605 Lions Ridge Road
Garfield County, Colorado
Michael and Tammy,
CBO Inc. completed an onsite wastewater treatment system (OWTS) septic tank replacement design for
the subject residence. The 18.049-acre property is located outside of Carbondale, in an area where
OWTSs are necessary.
Legal Description: Section: 30 Township: 7 Range: 87 Subdivision: LION'S RIDGE EST. Lot: 15
Parcel ID: 2391-304-01-015
SITE CONDITIONS
A 5-bedroom, single-family residence presently exists and is utilizing an existing OWTS. The OWTS is
documented by Garfield County Individual Sewage Disposal System Permit 1845 which received final
approval on November 16, 1990. The system was sized to accommodate 3-bedrooms. The OWTS was
inspected by Altitude Septic and results of the inspection are documented in a report dated November
30, 2021 (enclosed).
The OWTS consists of one 1000-gallon, two-compartment septic tank followed by a seepage pit, or
drywell, documented as 14’ x 14’ x 10’ below the inlet.
The residence will be remodeled, resulting in 5 total bedrooms.
The residence is served potable water form a community water system. The proposed septic tank will
not come within 25-feet of the water line.
The existing seepage pit appeared to be functioning normally at the time of Altitude Septic’s inspection.
The intent is to continue to use the existing STA.
DESIGN SPECIFICATIONS
The existing septic tank will be abandoned in place by pumping the septic tank and crushing the top,
bottom, and sides and filling the void with onsite material.
Design Calculations:
5 bedrooms = min. 1500-gallons septic tank capacity
Page 2
The sewer line from the house must be verified as having a minimum 2% fall to the new septic tank and a
double-sweep clean out installed between the house and new septic tank if one does not already exist.
A new, 1500-gallon, two-compartment Infiltrator® poly septic tank with an Orenco Biotube Effluent filter
on the outlet tee must be installed. Other state-approved poly septic tanks or a Valley Precast concrete
septic tank may be substituted, depending on availability. Risers must bring the manhole lids to grade.
We recommend Orenco® risers and lids. If more than 1-foot of risers are installed, a handle extension
must be added to the effluent filter.
For the purposes of this OWTS design, Benchmark Elevation has been established as 100’ as the sewer
line exiting the residence. Elevation of the septic tank placement must align with the existing sewer
line exiting the residence and the existing sewer line to the seepage pit. CBO Inc. should be
notified of any discrepancies or problems with grade elevations of proposed components during
installation of the OWTS.
Access to the existing seepage pit must be gained with risers and a manhole lid to provide access for
future inspection and monitoring.
Table 1 below compares the size of the existing seepage pit to sizing requirements for the proposed
remodel.
The documented percolation rate is an average of 7.2 minutes per inch (MPI). The original percolation
test conducted by Sun Peak Engineering out of Woodland Park, Colorado is enclosed with documents
provided by Garfield County. This percolation rate correlates to Soil Type 1 (Sand, Loamy Sand),
described in current Garfield County OWTS Regulation.
Current OWTS Regulation Calculations
75 GPD x 2 persons/bedroom x 3 bedrooms = 450 GPD + 150 GPD (4th and 5th Bedrooms) = 600 GPD
ESTIMATED WASTEWATER FLOW = 600 GPD
LTAR = 0.8 gallons / SF (Soil Type 1)
600 GPD / 0.8 gal/SF = 750 SF
Table 1
Existing Current OWTS Regulations
Tank Size 1000-gallon, two-compartment
septic tank
Estimated Wastewater Flow = 600
GPD = Min. 1500 gallons
Existing septic tank must be
replaced with a new, 1500-galllon
septic tank
Soil Treatment Area
(STA)
Soil Type 1
Seepage Pit
Infiltrative area = 14’ x 14’ x 10’
deep
14’ x 14’ = 196 SF (bottom area)
10’ x 14’ x 4 = 560 SF (sidewall)
Total Seepage Pit = 756 SF
Infiltrative area = Min. 750 SF
In summary, existing seepage pit appears to meet minimum sizing standards under current OWTS
Regulations for 5 total bedrooms.
Altitude Septic recommends jetting the sewer line from the septic tank to the STA as it has a
build-up from years of use.
Page 3
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.
COMPONENT MANUFACTURER MODEL NO. COMMENTS
Septic Tank Infiltrator Item # IM-1530-2CP 2-compartment poly
septic tank
Tank Risers and Lids Orenco® Double-walled PVC Risers and
Lids (24” diameter)
Effluent Filter Orenco® Full size effluent filter
Risers and Lid Valley Precast TBD with measurement
of manhole access
Risers and lid will bring existing
seepage pit access to grade
Construction must be according to Garfield County On-Site Wastewater Treatment System Regulations, the
OWTS Permit provided by Garfield County Environmental Health Department, and this design.
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.
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.
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.
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.
Page 4
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
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 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.
Carla Ostberg, MPH, REHS
1 StoryWood Frame Housew/ WalkoutDeckDeck-AboveConcrete- BelowConcreteDrivewayConcreteStepsGasFenceFence
GravelDrivewayGravelDrivewayTie RetainingWallSiteNo. 5 Rebar &Yellow Plastic CapIllegible2-1/2" Aluminum CapLS No. 31944S1/16 Corner Section 29 & Section 30Bears N01°24'05"W 1.74'Cabin18' x 7.5'7.76'No. 5 Rebar &1-1/2" Aluminum CapLS No. 11204No. 5 RebarNo. 5RebarNo. 5 RebarBikeRampAdjoiningAsphaltDrivewayCMPGate1 StoryWood Frame Housew/ Walkout(See Detail)63.90'251.89'Lot 1518.05 Acres ±Lions Ridge Road(60' R-O-W)Dirt DriveGravel Drivewayfor Lot 1Lot 1Lions Ridge EstatesReception No. 298350Lot 14Lions Ridge EstatesReception No. 298350Lot 2Lions Ridge EstatesReception No. 298350Gravel Driveway30.00' Waterline EasementPer Plat40.00' Private Road &Utility EasementPer Plat7.50' General Purpose Utility Easement12.00' General Purpose Utility Easement12.00' General Purpose Utility Easement7.50' General Purpose Utility Easement10.00'Setbacks Per Book 536, Page 813Street Lot Line= 30 feetSide Lot Lines= 25 feetRear Lot Lines= 30 FeetLot 2Stirling Ranch PUDParcel Number 239130405002MCARTHUR, SHANNON & JESSICA218 DERONDO STREETPANAMA CITY BEACH FL 32413Parcel Number 239129300277ROJO, MIGUEL A333 CREST POINT DRIVECARBONDALE, CO 81623Lot AMessenger SubdivisionExemptionParcel Number 239129305005SKIPPER DRIVE LLCPO BOX 3302ASPEN CO 81612LJM PROPERTIES LLC1663 BRIGHTWATERS BLVD NESAINT PETERSBURG FL 33704Lot 4Stirling Ranch PUDLot 5Stirling Ranch PUDBasis of BearingAsphalt RoadParcel Number 239130401001OWEN, NELSON & DIANE0222 CREST POINT DRIVECARBONDALE CO 81623-8947Parcel Number 239130401002READ, MARK & AMANDA616 LIONS RIDGE ROADCARBONDALE CO 81623Parcel Number 239130401014HEUER, THOMAS L REVOCABLE TRUST & HEUER,567 LIONS RIDGE ROADCARBONDALE CO 81623TieTie20.00' Access EasementFound MonumentNo. 5 Rebar & 1-1/4" YellowPlastic Cap LS No. 38342 SetUnderground Gas Line MarkerWater Shut-offElectric MeterTelephone PedestalCable PedestalWater ValveElectrical TransformerWater Tank LidSignLEGENDVICINITY MAPSCALE: 1" = 1000'PROPERTY DESCRIPTION:LOT 15LION'S RIDGE ESTATESACCORDING TO THE PLATRECORDED OCTOBER 9, 1979 AT RECEPTION NO. 298350.COUNTY OF GARFIELD,STATE OF COLORADOSURVEYOR'S CERTIFICATE:I, SCOTT R. BLACKARD, BEING A PROFESSIONAL LAND SURVEYOR IN THE STATE OF COLORADO, DO HEREBY CERTIFY TO:*LAND TITLE GUARANTEE COMPANY, FILE NO. BAR64004065, EFFECTIVE DATE OF FEBRUARY 26, 2021THAT THIS IMPROVEMENT SURVEY WAS PREPARED FROM AN ACTUAL MONUMENTED LAND SURVEY OF THE PROPERTY CORNERMONUMENTS, BOTH FOUND AND SET, UNDER MY DIRECT SUPERVISION AND CHECKING; THAT IT IS CORRECT TO THE BEST OF MYBELIEF AND KNOWLEDGE AND THAT ALL DIMENSIONS, BOTH LINEAR AND ANGULAR WERE DETERMINED BY AN ACCURATE CONTROLSURVEY IN THE FIELD WHICH BALANCED AND CLOSED WITHIN A LIMIT OF 1 IN 15,000 (WHICH COMPLIES WITH COLORADOPROFESSIONAL STANDARDS FOR A LAND SURVEY PLAT AND THE CURRENT ACCURACY STANDARDS FOR ALTA/ACSM LAND TITLESURVEYS): I FURTHER CERTIFY THAT THE IMPROVEMENTS ON THE ABOVE DESCRIBED PARCEL ON THIS DATE, MAY 13, 2021, EXCEPTUTILITY CONNECTIONS, ARE ENTIRELY WITHIN THE BOUNDARIES OF THE PARCEL, EXCEPT AS SHOWN, THAT THERE ARE NOENCROACHMENTS UPON THE DESCRIBED PREMISES BY IMPROVEMENTS ON ANY ADJOINING PREMISES EXCEPT AS INDICATED, ANDTHAT THERE IS NO APPARENT EVIDENCE OR SIGN OF ANY EASEMENT CROSSING OR BURDENING ANY PART OF SAID PARCEL, EXCEPTAS NOTED.________________________________________________________________________________________SCOTT R. BLACKARD P.L.S. 38342 DATEsblackard11@gmail.comIMPROVEMENT SURVEY PLAT OFLOT 15, LION'S RIDGE ESTATESCOUNTY OF GARFIELD, STATE OF COLORADO605 LIONS RIDGE RD, CARBONDALE, CO 81623US SURVEY FOOT USEDEXCEPTIONS FROM SAID TITLE COMMITMENT:8. RIGHT OF WAY FOR DITCHES OR CANALS CONSTRUCTED BY THE AUTHORITY OF THE UNITED STATES ASRESERVED IN UNITED STATES PATENT RECORDED APRIL 03, 1922 IN BOOK 112 AT PAGE 371, AND RECORDEDFEBRUARY 06, 1964 IN BOOK 355 AT PAGE 547.9. EXCEPTING AND RESERVING, ALSO, TO THE UNITED STATES ALL OIL, GAS, POTASH AND SODIUM IN THELAND SO PATENTED AND TO IT, OR PERSONS AUTHORIZED BY IT, THE RIGHT TO PROSPECT FOR,MINE AND REMOVE SUCH DEPOSITS FROM THE SAME UPON COMPLIANCE WITH THE ACT OF JULY 17, 1914 (38STAT. 509), AS AMENDED BY THE ACT OF MARCH 04, 1933 (47 STAT. 1570), AS RESERVED IN UNITED STATESPATENT RECORDED FEBRUARY 06, 1964 IN BOOK 355 AT PAGE 547.10. TERMS, CONDITIONS, RESTRICTIONS AND OBLIGATIONS AS CONTAINED IN AGREEMENT BY AND BETWEENALAN A. STOREY AND F.B. DASHNER RECORDED OCTOBER 09, 1979 IN BOOK 536 AT PAGE 822.11. TERMS, CONDITIONS, RESTRICTIONS AND OBLIGATIONS OF WATER USE AND EASEMENT AGREEMENT BYAND BETWEEN ALAN A. STOREY AND CHARLES E. WORTH AND ANN G. WORTH RECORDED OCTOBER 09, 1979IN BOOK 536 AT PAGE 827.12. TERMS, CONDITIONS, RESTRICTIONS AND OBLIGATIONS OF SUBDIVISION IMPROVEMENT AGREEMENT FORLION'S RIDGE ESTATES RECORDED OCTOBER 09, 1979 IN BOOK 536 AT PAGE 837.13. TERMS, CONDITIONS, RESTRICTIONS AND OBLIGATIONS OF LION'S RIDGE ESTATES HOMEOWNERSASSOCIATION RECORDED OCTOBER 09, 1979 IN BOOK 536 AT PAGE 741.14. EASEMENTS, CONDITIONS, COVENANTS, RESTRICTIONS, RESERVATIONS AND NOTES ON THE PLAT OF LION'SRIDGE ESTATES RECORDED OCTOBER 09, 1979, UNDER RECEPTION NO. 298350.15. RESTRICTIVE COVENANTS, WHICH DO NOT CONTAIN A FORFEITURE OR REVERTER CLAUSE, BUT OMITTINGANY COVENANTS OR RESTRICTIONS, IF ANY, BASED UPON RACE, COLOR, RELIGION, SEX, SEXUAL ORIENTATION,FAMILIAL STATUS, MARITAL STATUS, DISABILITY, HANDICAP, NATIONAL ORIGIN, ANCESTRY, OR SOURCE OFINCOME, AS SET FORTH IN APPLICABLE STATE OR FEDERAL LAWS, EXCEPT TO THE EXTENT THAT SAIDCOVENANT OR RESTRICTION IS PERMITTED BY APPLICABLE LAW AS CONTAINEDIN INSTRUMENT RECORDED OCTOBER 09, 1979, IN BOOK 536 AT PAGE 813 AND AS AMENDED IN INSTRUMENTRECORDED OCTOBER 17, 1979, IN BOOK 537 AT PAGE 844 AND AS AMENDED IN INSTRUMENT RECORDED JUNE24, 1997, IN BOOK 1023 AT PAGE281.16. TERMS, CONDITIONS, PROVISIONS AND OBLIGATIONS OF AGREEMENT RECORDED DECEMBER 1, 1999 INBOOK 1162 AT PAGE 808.17. TERMS, CONDITIONS AND PROVISIONS OF ACCESS EASEMENT AGREEMENT RECORDED DECEMBER 31, 2002IN BOOK 1422 AT PAGE 726.18. TERMS, CONDITIONS AND PROVISIONS OF EASEMENT GRANT RECORDED JANUARY 02, 2003 IN BOOK 1423AT PAGE 209.19. TERMS, CONDITIONS, PROVISIONS AND OBLIGATIONS OF ASSIGNMENT AND CONVEYANCE RECORDED APRIL11, 2007 AS RECEPTION NO. 720926.20. TERMS, CONDITIONS AND PROVISIONS OF MEMORANDUM OF WATER ALLOTMENT CONTRACT RECORDEDSEPTEMBER 20, 2016 AT RECEPTION NO. 882644.PO BOX 912SILT, CO 81652970-456-3081NOTES:1.) THE DATE OF THE FIELD SURVEY WAS AUGUST 11,2020.2.) ALL BEARINGS RELATIVE TO A BEARING OF S89°58'15"EALONG THE NORTH BOUNDARY LINE AS SHOWN HEREON.3.) THIS DOES NOT REPRESENT A TITLE SEARCH BY THISFIRM OR SURVEYOR.IMPROVEMENT SURVEY PLAT OFLOT 15, LION'S RIDGE ESTATESCOUNTY OF GARFIELD, STATE OF COLORADO605 LIONS RIDGE RD, CARBONDALE, CO 81623HOUSE DETAILSCALE: 1" = 20'ACCESS EASEMENT DESCRIPTION:A STRIP OF LAND 20.00 FEET IN WIDTH FOR THE PURPOSEOF AN ACCESS EASEMENT BEING A PORTION OF LOT 15,LIONS RIDGE ESTATES, RECORDED AS RECEPTION NO.298350. SAID STRIP OF LAND BEING MORE PARTICULARLYDESCRIBED AS FOLLOWS:COMMENCING AT THE SOUTHEAST CORNER OF SAID LOT15; THENCE N89°48'55"W 929.77 FEET TO A POINT ON THESOUTH BOUNDARY LINE OF SAID LOT 15, THE TRUE POINTOF BEGINNING; THENCE ALONG THE CENTERLINE OF ANEXISTING GRAVEL ROAD AS CONSTRUCTED AND IN PLACEN32°18'13"W 100.14 FEET; THENCE ALONG SAIDCENTERLINE N48°26'19"W 47.62 FEET; THENCE ALONG SAIDCENTERLINE N77°04'35"W 61.76 FEET TO A POINT ON THESOUTH LINE OF AN EXISTING EASEMENT AS SHOWN ONTHE PLAT OF LIONS RIDGE ESTATES. THE POINT OFTERMINUS. SIDELINES TO BE SHORTENED ORLENGTHENED TO CLOSE WITH BOUNDARY LINES.
!
!"#$%#&
'($'"& !
!"
)%)#*#
+'&" ,-
.'**/)
!"#$%#&'
'($'"&
!
#
0
$
11 0
1!1 0
2311
"4 5 31133'*
%&'
!
"
(
)
*
+ ( "
"6'2244
+789
*:
" 2
*
8
6
;
<4
=
!"
,
-)
. /