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August 28,2018 Project No. C1406
Erich Kaiter
ekaiter@comcast.net
Subsurface lnvestigation and Onsite Wastewater Treatment System Design
S-Bedroom Residence + 2-Bedroom ADU
7484 CR 100
Garfield County, Colorado
Erich,
ALL SERVICE septic, LLC performed a subsurface investigation and completed an onsite wastewater
treatment system (OWTS) design for the subject property. The 7.98-acre property is located outside of
Carbondale, in an area where OWTSs and wells are necessary.
Legal Description: Section: 18 Township: 7 Range: 87 TR lN LOT 147.98 ACRES
Parcel lD: 2391-181-00-025
SITE CONDITIONS
A S-bedroom, single-family residence presently exists and a 2-bedroom, additional dwelling unit (ADU) is
proposed above the detached garage. The existing OWTS serving the residence is experiencing
problems and there is a desire to upgrade the system.
The residence is served potable water by a private well on the property located southeast of the
residence and west of the driveway. The well is located greater than 104-feet1 from the proposed soil
treatment area (STA), greater than S0-feet from the proposed septic tanks, and greater than S0-feet from
any sewer line unless the sewer line is properly encased (see W4.0/2 Encasement Detail).
A seasonal stream bisects the property. The proposed STA will be located a minimum of 54-feet from
the stream. The sewer line will also cross the stream. The sewer line must be properly encased (see
W4.Ol2 Encasement Detail) inside of all minimum setbacks. Both lines existing the Automatic Distributing
Valve (ADV) may be encased in one single encasement pipe.
The proposed STAs will parallel the lower driveway in order to meet minimum stream setbacks. The
proposed STA slopes to the south toward the driveway. The STAs must be staked prior to installation
to assure setbacks are met.
I The '8-foot' rule applies to minimum setback distances with a design flow exceeding 1000 gallons per
day.
Page2
SUBSURFACE
The subsurface was investigated on July 31,2018 by digging two soil profile test pit excav_ations (Test Pits)
A visual and tactile soil analysis was completed by Carla Ostberg at the time of excavation.2
The materials encountered in the Test Pit #1 consisted of medium brown topsoil to 1.O-foot, underlain by
light brown to tan caliche to a maximum depth explored of 6.O-feet. No bedrock or groundwater was
encountered.
The materials encountered in Test Pit #2 consisted of medium brown topsoil to 1.O-foot, underlain by light
brown to tan caliche to a maximum depth explored of 8.O-feet.
A tactile analysis of the soils was taken from Test Pit #1 at 3-feet below grade. Soil structure grade was
moderate. The soil formed a ball and a ribbon lessthan 1-inch in length before breaking. Soil structure
shape was loose to blocky and consistence was friable to firm. Soil texture was more smooth than gritty.
Soils are consistent with Soil fype 2. The proposed design is an over-excavated, unlined sand filter with
a minimum of 2-feet of sand filter material3 STA. Sizing is based on Secondary Sand. A long term
acceptance rate (LTAR) of 0.8 gallons per square foot will be used to design the OWTS, in
accoidance with Garfield County On-Site Wastewater Treatment System Regulations.
Test Pit #1 backfill
2 Carla Ostberg holds a Certificate of Attendance and Examination from the CPOW Visual and Tactile
Evaluation of Soils Training.
3 Secondary Sand Filter Material must have an effective size of 0.15-0.60 mm, uniformity coefficient of
<7.0, percent files passing#200 sieve of < 3.0.
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Page 3
Sieved sample
Test Pit #2
Looking toward Test Pit #2
backfill
Page 4
DESIGN SPECIFICATIONS
The existing septic tank will be properly abandoned by pumping and crushing the top, bottom, and sides
and filling tñe void with on-site material. The existing STA will be abandoned in place.
Desiqn Calculations:
Average Desrgn Flow = 75 GPD x 2 people/bedroom x 7 Bedrooms = 1050 GPD
LTAR = 0.8 GPD/SF (Secondary Sand)
1050 GPD / 0.8 GPD/SF = 1312.5 SF
(2) 12'x 55' over-excavated, unlined sand filters
The new OWTS design is based on 7-bedrooms. An average daily wastewater flow of 1050 GPD will be
used.
A 4-inch diameter SDR-35 sewer line with a double sweep clean out must exist the detached garage and
have a minimum 2o/o grade to a new, 1ooo-gallon, two-compartment Valley Precast concrete septic tank
with an effluent filter o'n the ouflet tee. A 4-inch diameter SDR-35 sewer line with a minimum 1% fall must
be installed from the outlet of this septic tank to a new, 2000-gallon, two-compartment, Valley Precast
concrete septic tank with an Orenco@ pumping system in the second compartment of the septic tank to
serve the main house. A new, 4-inch diameter SDR-35 sewer line with a double sweep clean out and
minimum 2o/o grade must be installed from the main house to the 2000-gallon septic tank. We
recommend utiizing a "wye" fitting to connect the sewer line from the 1O00-gallon septic tank to the
sewer line prior to entering the 2000-gallon septic tank'
Manhole lids of both septic tanks must be brought to grade for access. lf more than 1-foot of risers are
used, handle extensions must be added to the filters.
An Orenc@ Biotube Pump Vault and an Orenco@ PF3005 pump will be placed in the second compartment
of the 2000-gallon septic tank. The floats should be set to dose approximately 80 gallons each pump cycle,
allowing apploximateiy 15 gallons of drain back after each pump cycle. The control panel for the pump must
ue locãted within ¡ine of sght of the septic tank. We recommend Valley Precast out of Buena Vista be
contracted for start-up of the pumping system.
A 1.S-inch diameter Schedule 40 pump line must be installed from the pump to an Orenco@ automatic
distributing valve (ADV), model 6402. This pump line must have a minimum 1o/o grade for proper drain back
into the ta-nk after each'pump cycle. The ADV must be placed a high point in the system and be placed in
an insulated riser with access fiom grade. Screened rock must be placed below the ADV to support the
ADV and to assure the clear pipes existing the ADV remain visible for future inspection and maintenance.
Effluent will be pressure dosed through a 1.S-inch diameter pump lines to two over-excavated, 12' x55'
unlined sand filiers with a minimum of 2-feet of sand filter material. 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. The gradation must be dated no more than one month prior to the
installation date.
pipes used to disperse the effluent must be surrounded by washed coarse screened gravel or crushed
stòne. All of the gravel or stone must pass a2lr-inch screen and must be retained on aT¿-inch screen. The
manifold must bã 1.5-inches in diameter. Laterals must be 1.S-inches in diameter with 5/32-inch diameter
orifice holes facing down, spaced 4-feet on center. Laterals will be separated by 3.O-feet. Each 1.5-inch
diameter lateral must end in a sweeping ell facing up with a ball valve for flushing. A soil separation fabric
should be placed over the gravel layer fôllowed by approximately 1-foot of topsoil or other suitable soil able
to support vegetative growth.
Page 5
The component manufacturers are typical of applications used by contractors and engineers in this area.
Alternatives may be considered or recommended by contacting our office. Construction must be
according to Garfield County On-Site Wastewater Treatment System Regulations, the OWTS Permit
provided by Garfield County Building Department, and this design.
REVEGETATION REQUIREM ENTS
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 irritation 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 backfilled STAs. 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.
lf an effluent filter or screen has been installed in the OWTS, we recommend this filter or screen be cleaned
annually, or as needed. lf 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
lf 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.
Excavation equipment must not drive in 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.
INSTALLATION OBSERVATIONS
ALL SERVICE septic, LLC must view the OWTS during construction. The OWTS observation should be
performed before backfill, after placement of OWTS components. Septic tanks, distribution devices,
Page 6
pumps, dosing siphons, and other plumbing, as applicable, must also be observed, ALL SERVICE septic,
LtC'snould bã notified 48 hours in advance to observe the installation.
LIMITS:
The design is based on information submltted. lf soil conditions encountered are different from conditions
describeã in report, ALL SERVTCE septic, LLC should be notified. All OWTS construction must be
according to the county regulations. Requirements not specified in this report must follow applicable
ðounty rägulations. Thê cıntractor should have documented and demonstrated knowledge of the
requiremeñts 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,
ALL SERVICE septic, LLC
Reviewed By:
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Richard FICarla Ostberg, MPH, REHS
8ffi82
DRAWINGS MUST BE USED IN
CONJUNCTION WITH DESIGN
LETTER DATED O8I28I1B0' 25', 50'
Scale: l'= 50'=0"
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EXISTING OWTS
TO BE
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Carbondale, Colo€do 8'1623
Phone 970.309.5259
carla@allssry¡æsept¡c.æm
Kaiter Residence
7484 CR 100
Garfield County, ColoEdo
PrcjectNumbêr: C1406
Date: 08/28/18 I
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33 Four Wheel Drive Road
Carbondale, Colorado 81623
Phone 970.309.5259
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Kaiter Residence
7484 CR 100
Garfisld County, ColoEdo
Prcj€ct Numbsr; Cf406
33 FourWheel Drive RoadCarbondale, Cdo€do 81623Phone 970.309.5259ærlâ@âllsruicæeptic.æmDESIGNs€EDROOM RESIDENCE + 2-BEDROOM ADU(75 GAJPERSON/DAY x 2 PERSONS/BEDRoOM x 7 BEDROOMS) WASTEWATERSLIP-ON PVC CAPDO NOT GLUEFLOW = 1050 GALLONS/DAYTANK:M¡N. 7 BEDROOMS =18,00 GALLONS + PUMP CAPACITYRECOMMEND lOOGGALLONS, TWO COMPARTMENT SEPTIC TANK SERVING ADU2OOGGALLON, TWO-COMPARTMENT SEPTIC TANK WTH PUPMING STATIONSERVING MAIN HOUSEINSULATEDTRACER WIREFINISHED GRADESOIL TREATMENT AREA (STA):LONG TERM ACCEPTANCE RATE (LTAR) = 0.8 GAU SQ FT (SECONoARY SAND)CALCULATED STA = CyLTAR = 1050 / 0.8 = 1313 SFPRESSURE DOSED, OVER-EXCAVATED, UNLINED SAND FILTER = 1313 SFMIN. 2'SANO FILTER MATERIAL (SECONDARY SAND)(2) 12'X 55' OVER-EXCAVATED, UNLINED SAND FILTERS4' DIA SDR-35SEWER LINETO TANKTO HOUSESCH{PUMPLINE30'DIAMETER PVC(MrN 1% OUNffiTOTñt9RISERvqoã, aæsrBEAT GWq LOME ÄI HIGHPOIM.5'DIN SHO PUMP LINE TOSffiPING ELL Frc¡NG UPW ASECOND BÐ, æTH LINESTO BELOdEO IN ONEæNCHÆCESIBG AT GæE1.5' DIA SCH4 PUMP LINE(MIN 1%TO WIFru)1.5" DtASCH40 ffiW|FOþMIAUTOMATICDISTRIBUTINGVALVE ASSEMBLYINSPEqIø MTAT æHCORROFÐFROM EFFLUENTPUMPING SYSTEM1.5" DtA SCH-40PVC INLETANDOUTLETS12' x 55' PRESSUË rcED UNLINEDwD FTLTER (MrN. Zffi æcoNcffiEwD)wftTHffi 1.SDhg{rycuTEruumffDtaoRtFlcEs (wtH ffitFtG sHrED)FrcING DNN ÀT 4 O.C./A ADV DETAIL\.7 rcf rc*/-ã STA PLAN\Y MþsÆKaiter Residence7¡184 CR 100Garfi eld County, ColoEdoPrcjeciNumber C1406Date: 08/28il18 IIDæ¡snedBy: "tol W3.0Reviryed By: RHPIDem By: DD I Sheet3ofS
33 Four l¡\lheel Drive RoadCarbondale, Colorado 8 l 623Phon€ 970.309.5259æla@allseruiæseptic.æmSLIP-ON PVCSPRINKLER VALVEBOX AT GRADEDO NOT GLUE40END CAP MUST BEGLUED OR SECUREDIN A WATER TIGHTFASHION WITHUNDERGROUNDSEALANTFINISHED GRADEENCASEMENT PIPE4" DIA SDR-3540 RIGID ENDINSPECTION PIPECAP AT EACH ENDOF PIPESTA114" DIA HOLE DRILLEDINTO TWO SIDES OF PIPEFOR VENTILATION(BELOW SL|P ON CAP)HOLE DRILLED IN ENDCAP MUST ONLY BELARGE ENOUGH TOALLOW SEWER LINE TOFIT THROUGHMEDIA.5'DIASDR-35 SEWERLINE. MUST REST ONBOTTOM OF ENCASEMENTPIPE/.ÀENCASEMENT DETAIL\3r-6r-rfæ10'DIAVALVE BOXWITH SECURED LIDI.5" PVC SLIP X MALEPIPE THREADADAPTORWCAP1.5" DIA SCH-40 PVCFLUSHING VALVESINSPECTION PORT AT EACHCORNERWITH 5/32 DIA CRIFICES FACINGDOWN AT 4' O.C. INSTALL ORIFICESHIELDS ON EACH ORIFICE1.5' DIA BALLVALVELANDSCAPE FABRICON GRAVEL1.5" DtA SCH-40 PVCLONG SWEEP 90" ELBOWEæmSZE:0.10.æ UMUNIFOilñæEFFICIEF< Z¡PERCEM F|NS PASSTNG t2@ Slffi :3.0AGMOATION OFBE $ND MEDAUSEDMUST BE PROUOED. ffE GNANONMUST BE DAIÐ NO MOæ .m ilÊMONTH PROR TO ÊE INSTIUNON.FILTER MEDIACHAMBER END CAP1.5' DIA SCH-40 PVCSUSPENDED LAÏERALSTA SECÏON VIEWAFLUSHING VALVE\y2''t'Kaiter Residence7484 CR 100Garfi eld County, ColoEdoPrcjestNumb€r: C1406w4.0Date: 08128/18 IOes¡qneO Av: CgOlReviewed By: RHdDEmBy:DD ISheet 4 of 5
33 FourWheel Drive RædCarbondale, ColoEdo 81623Phone 970.309.5259cerla@allseru¡cæeptic.æmSECONDARY SAND SPECIFICATIONSEFFECTIVE SIZE: 0.10.60 MMUNIFORMITY COEFFICIENT < 7"0PERCENT FINES PASSING #2OO SIEVE < 3.0A GRADATION OF THE SAND MEDIA USEDMUST BE PROVIDED. THE GRADATIONMUST BE DATED NO MORE THAN ONEMONTH PRIOR ÏO THE INSTALLATION.SOIL PROFILE TEST Ptr NO. 1SOIL PROFILE TEST PIT NO. 2-0-1-23-4-5-6-7I_ ,,0MEDIUM BROWN TOPSOILMEDIUM BROWN TOPSOILTAN, DENSE. CALICHETAN, DENSE, CALICHESUGGESIËD ORIFICE GRIDFUuLTtsÈuoLEGENDl! top$il$lll €riche13o.c.-l*3'o.c._lNO GROUNDWATER OR BEDROCK ENCOUNTEREDDURING TRACK HOE EXCA\TATIONA SOILS LOG\9/---ffiîæORIFICÉS FACE DOWIIPLACE ORIFICE SHIELDS UNDERALLoRtFtcEsA ORIFICE GRIDs/ idþffKaiter Residence7¿t84 CR 100Garfi eld County, ColoEdoPrcjectNumb€r: C1406Date: 08/28/18 IIDesisnedBy: cB{ W5.0Reviewed By: RHfDEwn By: DD I sr,""ts ors
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DESIGN NO'IES¡ Design per performonce test PerASru C1227
o Top surfoce oreo 46.25 f(
r fc @ 28 do¡æ; concrete : 6,000 PSI
Min.
lnstollotion:
o Tonk to be set on 5" mln. sond
bed or peo grovelr Tonk to be bockfllled unlformly on
oll sldes ln llfts less thon 24" ond
mechonicolly compoctedr Excovoted moteriql moy be used for
bockfill, provided lorgo stones ore
removedr Excovotion should be dewotered ond
tonk filled with woter prior to being
put ln servlce for lnstollotlon wlth
woter toble less thon 2' below grode
r Meets C1644-06 for resilient
connectorg¡ lnlet ond Outlet identified obove pïpe
r Delivered complete wlth internol
piping
. 4' Moxlmum bury depth
f '--.-:¿.
t:
..-J-i
ClcrAffi
r TL( ilDl
bGrade
FloDdbþ Rubber
Sæhnt
6i ln
5i JN
Section
View
Digging Specs lnvert Dimensions Net Copocity Net Weight
11' Long x 7' Wide
56" below inlet
lnlet et Height nlet Side Outlet Totol Tonk Totol
68"525 gol 1010 gol 2620 lbs 9380 lbs 12000 lbs
ALLOWABLE BURY
(Bosed on Woter Toble)
WA'TER TABIE ALLOWABLE
FÁRTH FII I
0'- o'2'-O'
't' - 0'3'- 0'
2'-O'3'- O'
3'- O'+'- 0'
DRY 4'- 0'
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