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HomeMy WebLinkAbout1596 Gore Trl - 210715402002Work Classification:New
301 Bearden RD
Edwards CO 81632-
AddressOwner Information
Permit Status:Active
Project Address
210715402002
Permit Type:OWTS Permit
Permit NO.OWTS-4-18-18973
Expires:1/12/2019Issue Date:9/14/2018
Parcel No.
1596 GORE TRL EDWARDS, CO 81632-
Private Wastewater
System
Environmental Health
Department
P.O.Box 179
500 Broadway
Eagle, CO 81631-0179
Phone: (970)328-8755
Fax: (970)328-8788
Phone:(970)926-0442
Cell:
Inspection
For Inspections call:(970)328-8755
Inspections:
IVR
OWTS Final Inspection 095
PhoneEngineer(s)
(970)945-7988H-P KUMAR
Contractor(s)Phone Primary ContractorLicense Number
SPIEGEL CONSTRUCTION (970)904-0694 No31-18
KATHERINE L. & PETER R. DOLAN
Permitted Construction /Details:
Install OWTS exactly as depicted in the H-P Kumar design stamped, signed, and dated September 7,2018
by David A.Young, P.E.The system is designed to serve a new four bedroom single family residence.
The system consists of three pressurized, unlined, sand filter trenches, each receiving alternating doses
of effluent from an Orenco V6403 Automatic distributing valve located at the high point of the system. A
Valley Precast 1,500 gallon, three compartment top seam septic tank (Item #1500T-3CP-HH)equipped with
an Orenco PF 3005 pump in a biotube vault will dose effluent to the432 square foot (after taking 50%
adjustments for using chambers and pressure dosing)soil treatment area consisting of three trenches,
each containing 12 Infiltrator Quick 4 Plus Standard chambers placed atop three feet of concrete sand for
a total of 36 Infiltrator chambers.Piping details, including strength, orifice size and spacing are detailed
in the design packet.Be sure to incorporate scour protection under weep holes within the trenches.
Contact the design engineer and Eagle County Environmental Health well in advance of requesting
inspections.All inspections necessary to certify proper installation must be conducted by the design
engineer.System certification along with the record drawing and photos are required to be submitted to,
and approved by, Eagle County Environmental Health prior to the use of the system or occupancy of the
dwelling.
Issued by:Environmental Health Department, Eagle County, CO
September 14, 2018
Date
Customer Copy
Ray Merry
CONDITIONS:
1.THIS PERMIT EXPIRES BY TIME LIMITATION AND BECOMES NULL AND VOID IF THE WORK AUTHORIZED BY THE PERMIT IS NOT
COMMENCED WITHIN 120 DAYS OF ISSUANCE, OR BEFORE THE EXPIRATION OF AN ASSOCIATED BUILDING PERMIT
2.ALL INSTALLATIONS MUST COMPLY WITH ALL REQUIREMENTS OF THE EAGLE COUNTY INDIVIDUAL SEWAGE DISPOSAL SYSTEM
REGULATIONS ADOPTED PURSUANT TO AUTHORITY GRANTED IN C.R.S.25-10-101,et seq., AS AMENDED
3.THIS PERMIT IS VALID ONLY FOR CONNECTION TO STRUCTURES WHICH HAVE FULLY COMPLIED WITH COUNTY ZONING AND
BUILDING REQUIREMENTS.CONNECTION TO, OR USE WITH ANY DWELLING OR STRUCTURE NOT APPROVED BY THE ZONING AND
BUILDING DEPARTMENTS SHALL AUTOMATICALLY BE A VIOLATION OF A REQUIREMENT OF THE PERMIT, AND WILL RESULT IN
BOTH LEGAL ACTION AND REVOCATION OF THE PERMIT
4.CHAPTER IV, SECTION 4.03.29REQUIRES ANY PERSON WHO CONSTRUCTS, ALTERS OR INSTALLS AN INDIVIDUAL SEWAGE DISPOSAL
SYSTEM TO BE LICENSED
October 16, 2019
Peter and Katie Dolan
301 Bearden Road
Edwards, Colorado 81632
prdolan@gmail.com
RE: Final approval of the: Septic System Installation, OWTS-018973-2018
Property location: 1596 Gore Trail, Eagle County, Parcel 210715402002
Mr. & Mrs. Dolan:
This letter is to inform you that the above-referenced permit has been inspected and finalized. This
OWTS permit was approved and sized to serve a total of four (4) bedrooms.
Additional information about the maintenance your septic system needs can be accessed through
our website links, provided on the Environmental Health Department’s septic system resource page.
Be aware that changes in the use of your property or alterations of your building may require
commensurate changes to, or relocation of, your septic system. Landscape features, trees with tap
roots, irrigation systems and parking areas above the soil treatment area can cause premature
system failure. It is equally important that you notice and immediately repair dripping faucets and
hissing toilets as this will certainly cause the system to fail.
If you have any questions regarding this information, please contact us at (970) 328 -8755 and
reference the OWTS septic permit number.
Best Regards,
Claire Lewandowski, REHS
Environmental Health Specialist III
Attachments: Certification Letter and Design – Septic System Flyer – Final Letter
PUBLIC HEALTH & ENVIRONMENT
(970) 328-8755
FAX: (970) 328-8788
environment@eaglecounty.us
5020 County Road 154
Glenwood Springs, CO 81601
phone: (970) 945-7988
fax: (970) 945-8454
email: kaglenwood@kumarusa.com
www.kumarusa.com
Office Locations: Denver (HQ), Parker, Colorado Springs, Fort Collins, Glenwood Springs, and Summit County, Colorado
October 8, 2019
Peter and Katie Dolan
301 Bearden Road
Edwards, Colorado 81632
(prdolan@gmail.com)
Project No. 17-7-166.02
Permit No. OWTS-4-18-18973
Subject: Certification of Onsite Wastewater Treatment System, Proposed Residence, Lot 5,
Block 1, Filing 34, The Summit at Cordillera, 1596 Gore Trail, Eagle County,
Colorado
Dear Peter and Katie:
A representative of Kumar & Associates (formerly H-P/Kumar) observed the installation of the
Onsite Wastewater Treatment System (OWTS) for the residence currently under construction at
the subject site as required by the Eagle County Environmental Health Department. Our
observations and recommendations are presented in this report. The services are supplemental to
H-P/Kumar’s (now Kumar & Associates) agreement for professional services to Peter and Katie
Dolan dated February 10, 2017.
We previously designed the OWTS for the residence as submitted in our report dated September
7, 2018, Project No. 17-7-166.02. The system was designed for four bedrooms. The OWTS was
installed under Eagle County Permit Number OWTS-4-18-18973 by Spiegel Construction.
We performed our evaluations on September 28, October 1, 4 and 8, 2018. The OWTS
components observed included: sewer line, cleanout, septic tank, effluent line, automatic
distribution valve (ADV), control panel and soil treatment area (STA) and the locations of these
components. The installation and locations of the system components were verified as shown on
Figure 1. Pictures of the OWTS components made during the site visit are included with this
report. The distance locations to the septic tank shown on Figure 1 were made by taping.
On October 4, 2019, after power had been supplied to the pump, a pump performance test was
performed with adequate pump pressure observed.
It is our opinion that the OWTS was installed in general conformance with the above referenced
design.
PROPERTY LINELIMIT OF DISTURBANCEBUILDING ENVELOPEBUIL
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ACCESS, UTILITY, AND
DRAINAGE EASEMENT
GARAGE
LOWER LEVEL
MUD ROOM
LOWER LEVEL
SPA
ENTRANCE
MAIN LEVEL
LOWER LEVEL
OFFICE
LOWER LEVEL
GUEST ROOM
LOWER LEVEL
GUEST ROOM
UTILITY AND
DRAINAGE EASEMENT FIREPLACEMAIN FLOOR DECKMAIN LEVELLOWER LEVEL++CLEANOUT
VALLEY PRECAST 1,500
GALLON, THREE CHAMBER
SEPTIC TANK WITH AN
ORENCO PF3005 EFFLUENT
PUMP INSTALLED IN THE
THIRD CHAMBER
4" SEWER LINE
SLOPED 2%-4%
ORENCO V6403
AUTOMATIC
DISTRIBUTING
VALVE (ADV)
SOIL TREATMENT AREA
CONSISTING OF 3 TRENCHES
WITH 12 INFILTRATORS IN EACH
(36 TOTAL) PLACED ON 3 FOOT
THICK SAND FILTER
112" EFFLUENT
TRANSPORT LINE
CONTROL
PANEL
OWTS PHOTOGRAPH LOG
PROPOSED DOLAN RESIDENCE
LOT 5, BLOCK 1, FILING 34
THE SUMMIT AT CORDILLERA
1596 GORE TRAIL
EAGLE COUNTY, COLORADO
Project No. 17-7-166.02
Photograph 1: Cleanout and
sewer line exiting residence.
Photograph 2: Valley Precast
two-chamber 1,500 gallon septic
tank.
OWTS PHOTOGRAPH LOG
PROPOSED DOLAN RESIDENCE
LOT 5, BLOCK 1, FILING 34
THE SUMMIT AT CORDILLERA
1596 GORE TRAIL
EAGLE COUNTY, COLORADO
Project No. 17-7-166.02
Photograph 3: Septic tank with
sewer line entering and inlet tee.
Photograph 4: Effluent line
exiting septic tank and entering
automatic distribution valve
(ADV).
OWTS PHOTOGRAPH LOG
PROPOSED DOLAN RESIDENCE
LOT 5, BLOCK 1, FILING 34
THE SUMMIT AT CORDILLERA
1596 GORE TRAIL
EAGLE COUNTY, COLORADO
Project No. 17-7-166.02
Photograph 5: Orenco V6403
automatic distribution valve
(ADV).
Photograph 6: Effluent lines
and soil treatment area (STA)
with observation ports.
OWTS PHOTOGRAPH LOG
PROPOSED DOLAN RESIDENCE
LOT 5, BLOCK 1, FILING 34
THE SUMMIT AT CORDILLERA
1596 GORE TRAIL
EAGLE COUNTY, COLORADO
Project No. 17-7-166.02
Photograph 7: Trench in soil
treatment area (STA). Infiltrator
chambers on 3-foot sand filter
with observation ports.
Photograph 8: Graded STA.
OWTS PHOTOGRAPH LOG
PROPOSED DOLAN RESIDENCE
LOT 5, BLOCK 1, FILING 34
THE SUMMIT AT CORDILLERA
1596 GORE TRAIL
EAGLE COUNTY, COLORADO
Project No. 17-7-166.02
Photograph 9: Third chamber/
dosing chamber of septic tank.
Photograph 10: Control panel.
5020 County Road 154
Glenwood Springs, CO 81601
Phone: (970) 945-7988
Fax: (970) 945-8454
Email: hpkglenwood@kumarusa.com
Office Locations: Parker, Glenwood Springs, and Silverthorne, Colorado
ONSITE WASTEWATER TREATMENT SYSTEM DESIGN
PROPOSED RESIDENCE
LOT 5, BLOCK 1, FILING 34
THE SUMMIT AT CORDILLERA
1596 GORE TRAIL
EAGLE COUNTY, COLORADO
PROJECT NO. 17-7-166.02
SEPTEMBER 7, 2018
PREPARED FOR:
PETER & KATIE DOLAN
301 BEARDEN ROAD
CORDILLERA, COLORADO 81632
prdolan@gmail.com
Project No. 17-7-166.02
TABLE OF CONTENTS
INTRODUCTION ...................................................................................................................... - 1 -
PROPOSED CONSTRUCTION ................................................................................................ - 1 -
SITE CONDITIONS ................................................................................................................... - 2 -
SUBSURFACE CONDITIONS ................................................................................................. - 2 -
OWTS ANALYSIS .................................................................................................................... - 3 -
DESIGN RECOMMENDATIONS ............................................................................................ - 4 -
SOIL TREATMENT AREA................................................................................................... - 4 -
OWTS COMPONENTS ......................................................................................................... - 6 -
OWTS OPERATION AND MAINTENANCE.......................................................................... - 9 -
OWTS HOUSEHOLD OPERATION .................................................................................... - 9 -
OWTS MAINTENANCE ..................................................................................................... - 10 -
OWTS CONSTRUCTION OBSERVATION .......................................................................... - 11 -
LIMITATIONS ......................................................................................................................... - 11 -
FIGURES
FIGURE 1 OWTS SITE PLAN
FIGURE 2 USDA GRADATION TEST RESULTS
FIGURE 3 GRADATION TEST RESULTS
FIGURE 4 SOIL TREATMENT AREA CALCULATIONS
FIGURE 5 SOIL TREATMENT AREA PLAN VIEW
FIGURE 6 SOIL TREATMENT AREA CROSS SECTION
FIGURE 7 DISTRIBUTION LINE CLEANOUT DETAIL
ATTACHMENTS
VALLEY PRECAST SEPTIC TANK DETAIL
AUTOMATIC DISTRIBUTING VALVE DETAIL
ORENCO EFFLUENT PUMP CURVE
Project No.17-7-166.02
INTRODUCTION
This report provides the results of an onsite wastewater treatment system (OWTS) design for the
proposed residence to be located on Lot 5, Block 1, Filing 34, The Summit at Cordillera, 1596
Gore Trail, Eagle County, Colorado. The purpose of this report is to provide design details for
the OWTS in accordance with 2018 Eagle County Onsite Wastewater Treatment System
Regulation and the Colorado Department of Public Health and Colorado Environmental
Regulation #43. The services are supplemental to our agreement for professional services to
Peter and Katie Dolan dated February 10, 2017.
BACKGROUND INFORMATION
H-P/Kumar previously performed a subsoil study for foundation design of the residence at the
site and presented our findings in a report dated March 16, 2017, Project No. 17-7-166. A
preliminary OWTS design was done by us based on limited information from that study, report
dated April 4, 2018, Project No. 17-7-166.02. The current OWTS design was performed based
on site specific profile pit evaluations at the proposed soil treatment area.
PROPOSED CONSTRUCTION
The proposed construction consists of a four-bedroom residence located on the lot as shown on
Figure 1. The residence will be a two-story wood-frame structure with a walkout basement
level. Ground floors will be slab-on-grade. The OWTS soil treatment area (STA) will be
located downhill and northeast of the proposed residence. Water service will be provided to the
building via a utility easement extending from Gore Trail to the west. The basement level of the
residence will have a foundation drain.
If proposed construction is different than that described, we should be contacted to re-evaluate
our design recommendations.
Project No.17-7-166.02
- 2 -
SITE CONDITIONS
The lot was vacant with the foundation being excavated at the time of the field exploration. The
terrain slopes strongly to moderately down to the northeast at grades from about 5 to 20 percent
in most of the proposed building area and planned STA. The slope becomes steeper, on the
order of 30 to 50 percent in the eastern and northeastern parts of the lot. The steep slope
continues down a considerable distance beyond the east side of the building envelope. Elevation
difference across the proposed STA is about 5 feet, see Figure 1. Vegetation consists of grass
and weeds with scattered aspen and evergreen trees which become dense to the north and east of
the building envelope. We are not aware of any water wells on or near the lot.
SUBSURFACE CONDITIONS
The field exploration was conducted on May 22, 2018. Two profile pits (Profile Pits 1 and 2)
were excavated at the approximate locations shown on Figure 1 to evaluate the subsurface
conditions. Logs of the profile pits are provided below.
Log of Profile Pit 1
Depth USDA Classification
0-1½’ TOPSOIL; Sandy Loam, scattered gravel, very moist, dark brown.
1½’-8½’ VERY GRAVELLY LOAMY SAND; with gravel, cobbles and small boulders,
single grain structure, moist, brown.
• Disturbed bulk sample taken at 2½ to 3½ feet.
• Bottom of pit @ 8½ feet.
• No free water or redoximorphic features observed during excavation.
Project No.17-7-166.02
- 3 -
Log of Profile Pit 2
Depth USDA Classification
0-1’ TOPSOIL; Sandy Loam, scattered gravel, very moist, dark brown.
1’-8’ VERY GRAVELLY LOAMY SAND; with gravel, cobbles and small boulders,
single grain structure, moist, reddish brown.
• Disturbed bulk sample taken at 3 to 4 feet.
• Bottom of pit @ 8 feet.
• No free water or redoximorphic features observed during excavation.
The soils encountered consist of about 1 to 1½ feet of topsoil overlying Very Gravelly Loamy
Sand down to the depths explored of 8½ and 8 feet. Gradation analyses were performed on
disturbed bulk samples of the soils from Profile Pits 1 and 2, with the results provided on Figures
2 and 3. The tested samples classify as Very Gravelly Loamy Sand per the USDA system. The
soils in contained greater than 35 percent material larger than 2.0 mm and classify as Type R-0
per the State regulations due to the high rock content.
OWTS ANALYSIS
Based on the profile pit evaluations, the natural soils contain greater than 35 percent rock-sized
material and a sand filter on the natural soil will be needed for adequate treatment of the
wastewater effluent. The system will consist of three rows of Infiltrators in a trench
configuration over a minimum of 3 feet of sand. The STA will be sized for 4 bedrooms using an
LTAR of 0.8 gallons per square foot per day for the sand filter and natural coarse granular soils.
The sewage will gravity flow to the septic tank for primary treatment then to the dose chamber
where the effluent will be pressure dosed with a submersible effluent pump to the STA for
dispersal and final treatment. Equal distribution will be provided to the individual trenches by an
automatic distribution valve (ADV). Pumping to the STA is required by State and County
Regulations for the sand filter system treatment system.
Project No.17-7-166.02
- 4 -
A 100 feet minimum setback is required from the proposed STA to any on-site and off-site wells.
A 50 feet minimum setback is required from any wells to sewer and effluent lines and the
proposed septic and dose tanks. A 5 feet minimum setback is required from the septic and dose
tanks to the proposed residence. A 20 feet minimum setback is required from the STA to the
residence. A 25 feet minimum setback is required to potable water supply lines from the STA.
Based on our site observations there are no nearby active irrigation ditches.
DESIGN RECOMMENDATIONS
The design recommendations presented below are based on the proposed construction, the site
and subsurface conditions encountered and our experience in the area. Proposed locations of the
system components are provided on Figure 1. If conditions encountered during construction are
different than those that are described in this report, contact us to re-evaluate our design
recommendations.
SOIL TREATMENT AREA
• The treatment system will consist of three trenches with 12 Infiltrator Quick 4 Plus
Standard chambers in each trench (36 chambers total) placed on a minimum of 3 feet of
sand. Concrete sand is suitable as the sand filter material.
• Distribution lines, consisting of 1.5-inch diameter, Schedule 40 piping, with 3/16-inch
orifice holes drilled at 4-foot centers near the center of the infiltrators, should be installed
along the complete length of the infiltrators in each trench (Figure 5). The distribution
lines should be suspended approximately 2 inches from the top surface of the infiltrators
by pipe ties. The orifice holes should face up toward the infiltrator surface above.
• A ⅛-inch hole should be drilled on the bottom of each end of each distribution pipe to
allow for complete drainage of the distribution line following pressure dosing. Install
splash plates below drain holes.
• A pressure distribution system will be used to provide equal distribution to the Infiltrators
and trenches.
Project No.17-7-166.02
- 5 -
• The STA was sized based on an LTAR of 0.8 gallons per square feet per day for the
Loamy Sand soil below the 3 feet thick sand layer. An LTAR of 0.8 was also used for
the concrete sand filter material.
• Each chamber was allowed 12 square feet of area. A 20% reduction in the STA size was
applied for pressure dosing to a trench and a 30% reduction was applied for use of
Infiltrator chambers. The total STA is 432 square feet. Soil treatment area calculations
are shown on Figure 4.
• The trenches should be oriented along the ground contours to minimize soil cut and
cover.
• The sand filter material shall be placed in lifts not exceeding 10 inches. Each lift shall be
track or bucket compacted until settlement ceases.
• The base and sidewalls of the trench excavations should be scarified prior to the sand and
chamber placement.
• A minimum of 12 inches and a maximum of 24 inches of cover soil should be placed
over the chambers.
• Backfill and surface grading should be graded to deflect surface water away from the
STA and should be sloped at 3 Horizontal to 1 Vertical maximum. This will be
especially important along the up-slope side of the field where a swale may be needed.
• Disturbed soil should be re-vegetated as soon as possible with a native grass mix. No
trees, shrubs or other plants with deep roots should be planted on or near the absorption
area as this may damage the system piping.
• Four-inch diameter inspection ports should be installed vertically into the knockouts
provided in the Infiltrator end caps. Install vents at each end of each trench. The
inspection port piping should be screwed into the top to the chambers and should not
extend down to the ground surface inside the chambers. The inspection ports should
extend at least 8 inches above the finished ground surface or be protected in a valve box
at finished grade.
• A plan view of the STA is presented on Figure 5 and a cross section of the STA is
presented on Figure 6.
• Cleanouts are required in each of the distribution lines. See Figure 7 for the cleanout
detail.
Project No.17-7-166.02
- 6 -
OWTS COMPONENTS
Recommended OWTS components provided below are based on our design details and our
experience with the specific component manufacturers. Equivalent components may be feasible
but need to be approved by us prior to construction.
Septic Tank
• A 1,500-gallon, three chamber Valley Precast septic tank is proposed for primary
treatment, with the final chamber serving as a dose tank equipped with a submersible
effluent pump enclosed in an Orenco Biotube pump vault. A copy of the tank detail is
provided as an attachment to this report.
• The tank must maintain a 10 feet setback to the on-site water supply line.
• The tank must be a minimum of 5 feet from the proposed residence.
• The tank must be a minimum of 5 feet from the proposed STA.
• The tank must be set level. The excavation bottom must be free of large rocks or other
objects that could damage the tank during placement. A road base or gravel bedding
material may be necessary to prevent tank damage during placement and act as a leveling
course.
• Install tank with 2 feet minimum cover soil for frost protection. Maximum tank soil
cover depth is 4 feet.
• The septic lids must extend to final surface grade and made to be easily located.
Sewer Pipe
• The sewer line from the structure to the septic tank should not be less than the diameter
of the building drain and not less than 4 inches in diameter.
• The sewer pipes should have a rating of SDR35 or stronger. Schedule 40 PVC is
required beneath all driveway surfaces.
• The sewer pipe should be sloped between 2% to 4% to help limit disturbance of solids in
the tank and potential sewage bypass of the first chamber of the tank. If a steeper slope is
needed, this can be accomplished with vertical step-downs in the sewer line.
Project No.17-7-166.02
- 7 -
• A minimum 36 inches of cover soil should be provided over the sewer pipes. Paved
areas, patios or other areas without vegetative cover may be more susceptible to frost.
We recommend 48 inches of soil cover over the sewer pipe in these areas and the pipe be
insulated on top and sides with 2-inch-thick blue foam insulation board. If adequate soil
cover is not possible, we should be contacted for re-evaluation prior to installation.
• The sewer pipe should be bedded in compacted ¾ inch road base or native soils provided
that the native soils contain no angular rocks or rocks larger than 2½ inches in diameter
to help prevent settlement of the pipe. Sags could cause standing effluent to freeze and
damage piping.
• Install cleanout pipes within 5 feet of the building foundation, where the sewer pipe
bends 90 degrees or more, and every 100 feet of sewer pipe.
• All 90-degree bends should be installed using a 90-degree long-sweep or by using two
45-degree elbows.
• The sewer line location shown on Figure 1 is considered conceptual. We assume that
there will be only one sewer line exiting the building. It is the responsibility of the
owner/contractor to locate all sewer line exit locations and connections to the septic tank.
We should be notified if there are other sewer lines exiting the structure.
Effluent Transport Piping
• 1.5-inch diameter Schedule 40 effluent transport piping should be sloped at 2% minimum
to drain back to the dose chamber of the septic tank from the ADV after each pump cycle.
Distribution piping should be sloped a minimum of 2% to drain from the ADV to the
trenches after each pump cycle.
• The effluent transport pipe should be bedded in compacted ¾ inch road base or native
soils provided that the native soils contain no angular rocks or rocks larger than 2½
inches in diameter to help prevent settlement of the pipe. Sags could cause standing
effluent to freeze and damage piping.
• A minimum of 36 inches of cover soil should be provided over the effluent transport
pipe. Paved areas, patios or other areas without vegetative cover may be more
susceptible to frost. We recommend 48 inches of soil cover over the effluent pipe and
Project No.17-7-166.02
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insulation with at least 2 inches of rigid foam insulation in these areas. If adequate cover
soil is not possible the design engineer should re-evaluate soil cover prior to installation.
• The effluent pipe should be double encased with larger diameter Schedule 40 PVC pipe
underneath driveway surfaces and be provided with at least 48 inches of soil cover and be
insulated on top and sides with 2-inch-thick foam insulation board.
• All 90-degree bends should be installed using a 90 degree long-sweep or by using two
45-degree elbows.
Effluent Pumping System
• An Orenco PF3005, 115-volt, submersible effluent pump with a 1.25-inch diameter
discharge assembly, or equivalent, will be required for effluent pumping.
• The maximum effluent transport distance from the pump discharge to the ADV is
estimated to be 3 feet. The maximum distance from the ADV to the STA trenches is
estimated to be an additional 37 feet.
• The elevation difference from pump discharge up to the ADV is estimated to be 3 feet.
• The pump should be enclosed in an Orenco Biotube Pump Vault for effluent filtering and
protection of the pump from vibration.
• An equivalent pump must be capable of operating at 12.7 gallons per minute at 11.7 feet
of total dynamic head. A pump performance curve is provided as an attachment to this
report.
• The floats should be set to provide a dose volume of approximately 38 gallons. The
actual dose volume will be about 37 gallons assuming 1 gallon of drain-back in the
transport line. To achieve the desired dose volume, the upper (“ON”) and lower (“OFF”)
floats should be set approximately 3¾ inches apart.
• The flow differential between the first and last orifices is estimated to be 1.7%.
• The high-water alarm float should be placed approximately 3 inches above the “ON”
float in the dose tank. The high-water alarm must be wired on a separate electrical circuit
from the pump.
• A ⅛ inch diameter weep hole should be drilled in the effluent transport line prior to
exiting the dose tank so the transport line can drain after each pumping cycle.
Project No.17-7-166.02
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Automatic Distributing Valve
• An Orenco Systems V6403 Automatic Distributing Valve (ADV) will be used to
alternate doses to each trench. A copy of the ADV detail is provided as an attachment to
this report.
• The ADV must be installed level, with the correct side facing up, and must be the high
point in the system.
• The ADV should be installed in a valve box approximately 2 to 3 feet deep, such that it is
serviceable and protected from freezing. We recommend the ADV be equipped with heat
tape for additional freeze protection during winter months. We recommend the lid be
insulated with blue board and the void space inside of the box be filled with fiberglass
insulation.
• We recommend that the ground surface be graded away from the ADV in all directions.
Improper surface drainage could cause standing water to freeze and damage the valve
and/or piping.
• The valve has clear sections of pipe that should be inspected at least annually to ensure
that it is alternating doses to each trench.
OWTS OPERATION AND MAINTENANCE
The OWTS will require periodic inspection and maintenance to function properly. A properly
designed, installed and maintained system can greatly increase its lifespan. The level of
maintenance will vary depending on the complexity of the system and water use habits of the
residents. We recommend that an OWTS Operation and Maintenance (O&M) Manual be
developed. Depending on the complexity of the system a contract with an OWTS maintenance
provider may be prudent. Below are some basic recommendations for the OWTS O&M.
OWTS HOUSEHOLD OPERATION
• Use of high efficiency water fixtures is recommended to decrease the hydraulic load on
the OWTS system.
• Fix plumbing leaks immediately as this may cause a hydraulic overload of the STA.
Project No.17-7-166.02
- 10 -
• Do not irrigate the area on top of or directly upgradient of the STA as this may cause a
hydraulic overload.
• Do not dispose of household waste down household drains as this may clog or damage
OWTS components. Examples of household waste includes: dental floss, cotton swabs,
coffee grounds, paper towels, feminine products and many other kitchen and bath items.
• Use of kitchen garbage disposals is not recommended. If a garbage disposal is utilized,
kitchen wastewater should be screened thoroughly. Many kitchen solids are not
decomposed in the septic tank and may cause increased tank pumping frequency.
• Do not dispose of household chemicals, greases, oils, paints, hot tub water or water
softener backwash in household drains. A separate drywell, if feasible, may be necessary
for hot tub water or water softener backwash disposal.
• Limit the use of bleach as this may harm useful bacteria in the septic tank and STA.
• Liquid dishwasher and clothes washer detergent is recommended for households served
by an OWTS. Clay substances used as fillers in powder detergents may result in
clogging of the STA.
• The effluent in septic tanks can freeze during extended periods of non-use in cold
weather. We recommend that a tank heater be installed in this system to help prevent
freezing.
OWTS MAINTENANCE
• Inspect the septic tank, dose tank, Biotube pump vault, effluent pump and soil treatment
area at least annually for problems or signs of failure.
• The effluent filter should be cleaned annually by spray washing solids into the first
chamber of the septic tank.
• Septic tank should be pumped and cleaned every 3 to 5 years depending on use. Longer
pumping intervals may increase the amount of solids that reach the soil absorption area,
which may shorten its life span.
• Pumping of the septic tank should take place when the level of the sludge and scum
layers combined take up 25 to 33% of the capacity of the first chamber of the tank.
Project No.17-7-166.02
- 11 -
OWTS CONSTRUCTION OBSERVATION
The Eagle County Environmental Health Department requires that the designer of the system
provide a record drawing and certification of the OWTS construction (As-Built inspection). We
should be provided with at least 48-hour notice prior to the installer needing the inspections.
Prior to issuance of our certification letter, we require observation of all system components
prior to backfill. The number of site visits required for the inspection will depend on the
installer’s construction schedule.
LIMITATIONS
We have conducted this design in accordance with generally accepted engineering principles and
practices in this area at this time. We make no warranty either expressed or implied. The
recommendations provided in this report are based on the site conditions, profile pit evaluations,
soil texture analysis, the proposed construction and our experience in the area. Variations in the
subsurface conditions may not become evident until excavation is performed. If conditions
encountered during construction appear different from those described in this report, we should
be notified so that re-evaluation of the recommendations may be made.
This report has been prepared for the exclusive use by our client for design purposes. We are not
responsible for technical interpretations by others of our information. As the project evolves, we
should provide continued consultation and field services during construction to review and
monitor the implementation of our recommendations, and to verify that the recommendations
have been appropriately interpreted. Significant design changes may require additional analysis
or modifications to our design.
It is our opinion, that the designed location of the OWTS components does not violate any
setback requirements of the current Eagle County Regulations. Below is a table of common
minimum horizontal setbacks to OWTS components. Refer to the Eagle County Regulations for
a complete list of required setbacks. We recommend the OWTS components be surveyed by a
Professional Colorado Land Surveyor.
PROPERTY LINELIMIT OF DISTURBANCEBUILDING ENVELOPEBUIL
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ACCESS, UTILITY, AND
DRAINAGE EASEMENT
GARAGE
LOWER LEVEL
MUD ROOM
LOWER LEVEL
SPA
ENTRANCE
MAIN LEVEL
LOWER LEVEL
OFFICE
LOWER LEVEL
GUEST ROOM
LOWER LEVEL
GUEST ROOM
UTILITY AND
DRAINAGE EASEMENT FIREPLACEMAIN FLOOR DECKMAIN LEVELLOWER LEVEL++CLEANOUT
VALLEY PRECAST 1,500
GALLON, THREE CHAMBER
SEPTIC TANK WITH AN
ORENCO PF3005 EFFLUENT
PUMP INSTALLED IN THE
THIRD CHAMBER
4" SEWER LINE
SLOPED 2%-4%
ORENCO V6403
AUTOMATIC
DISTRIBUTING
VALVE (ADV)
SOIL TREATMENT AREA
CONSISTING OF 3 TRENCHES
WITH 12 INFILTRATORS IN EACH
(36 TOTAL) PLACED ON 3 FOOT
THICK SAND FILTER
112" EFFLUENT
TRANSPORT LINE
USDA GRADATION TEST RESULTS
1 MIN.
4 MIN.19MIN.15 MIN.60MIN.#325 #140 3/4"3/8"1 1/2"3"5"6"8"
DIAMETER OF PARTICLES IN MILLIMETERS
U.S. STANDARD SERIES CLEAR SQUARE OPENINGS
SIEVE ANALYSIS
TIME READINGS
HYDROMETER ANALYSIS
#4#10#18#35#60
7 HR
45 MIN.24 HR.
0
10
20
30
40
50
100
90
80
70
60
50
60
70
80
90
100
0
10
20
30
40
20315276.237.519.09.54.752.001.00.500.025.106.045.019.009.005.002.001
SILT COBBLESLARGE
GRAVEL
MEDIUMCOARSEMEDIUMV. FINE
SAND CLAY FINE V. COARSE SMALL
USDA SOIL TYPE:
GRAVEL %SILT %CLAY %
FROM:PROFILE PIT 1 @ 212 - 312 FEET
52 37 0SAND %11
VERY GRAVELLY LOAMY SAND
1 MIN.4 MIN.19MIN.15 MIN.60MIN.#200 #100 3/4"3/8"1 1/2"3"5"6"8"
DIAMETER OF PARTICLES IN MILLIMETERS
U.S. STANDARD SERIES CLEAR SQUARE OPENINGS
SIEVE ANALYSIS
TIME READINGS
HYDROMETER ANALYSIS
CLAY TO SILT COBBLESCOARSE
GRAVEL
FINECOARSEMEDIUMFINE
SAND
#4#8#16#30#50
7 HR
45 MIN.24 HR.
0
10
20
30
40
50
100
90
80
70
60
50
60
70
80
90
100
0
10
20
30
40
12.5 127
20315276.237.519.09.54.752.361.18.600.300.150.074.037.019.009.005.002.001
SAMPLE OF:
GRAVEL %SAND %SILT AND CLAY %
FROM:PROFILE PIT 2 @ 3 - 4 FEETVERY GRAVELLY LOAMY SAND
48 39 13
GRADATION TEST RESULTS
1.5" DIAMETER SCH.
40 NON-PERFORTED
PVC PIPE SLOPED AT
2% MIN. DOWN TO
EACH TRENCH
4 INCH DIAMETER PVC
OBSERVATION PORTS INSTALLED
VERTICALLY INTO KNOCKOUTS
PROVIDED IN END CAPS. INSTALL
VENTS AT EACH END OF EACH
TRENCH. REMOVABLE LID TO BE
PLACED ON TOP OF PIPE. PIPE
MUST STICK UP AT LEAST 8
INCHES ABOVE FINISHED GRADE.
PIPES SHOULD NOT EXTEND TO
SOIL SURFACE AND SHOULD BE
SECURED TO CHAMBER WITH
SCREWS OR COUPLINGS.
ORENCO V6403
AUTOMATIC DISTRIBUTING
VALVE (HIGH POINT)
INFILTRATOR QUICK 4
PLUS STANDARD
CHAMBER. 12
CHAMBERS PER ROW.
INFILTRATOR
QUICK 4 PLUS
STANDARD
END CAP
1.5" SCH. 40 PVC DISTRIBUTION PIPE
WITH 3 16" DIAMETER HOLES DRILLED AT
4 FOOT CENTERS ON TOP OF PIPE. 12
HOLES PER LATERAL. PERFORATIONS
TO BE PLACED NEAR CENTER OF EACH
INFILTRATOR. PIPE TO BE INSTALLED
LEVEL AND SECURED WITH 120 LB. MIN.
TENSILE STRENGTH CABLE TIES AT
EACH END OF EACH CHAMBER.
DRILL ONE 18" DIAMETER HOLE ON BOTTOM
OF EACH END OF EACH DISTRIBUTION PIPE
TO ALLOW FOR COMPLETE DRAINAGE.
INSTALL SPLASH PLATES BENEATH DRAIN
HOLES.MA
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CLEANOUTS INSTALLED AT
EACH END OF EACH
DISTRIBUTION LATERAL.
SEE FIGURE 7 FOR DETAIL.4' minLine Flow From Tank1.5" DIAMETER SCH. 40
NON-PERFORATED PVC PIPE
SLOPED AT 2% MIN. TO DRAIN
BACK TO DOSE TANK
APPROXIMATE SCALE
1 INCH 20 FEET
Notes
1.Chambers should be installed level on concrete sand placed in 10-inch lifts on scarified natural ground surface.
2.All piping should have a rating of Schedule 40.
3.Changes to this design should not be made without consultation and approval by a representative of HP-Kumar.
Infiltrator Quick
4 Plus Standard
End Cap
Infiltrator Quick 4 Plus
Standard Chamber
Installed Level
Approx. E
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12" min. 24" max. Cover
Soil Graded to Deflect
Surface Water
Scarify ground surface
prior to sand placement.
Undisturbed Soil
Between Trenches
1ative Soil
Pressure pipe drill location
Minimum 3 feet of
concrete sand placed in
10 inch lifts.
4' min.
1otes
1.Chambers should be installed level on concrete sand. Concrete sand to be
placed in 10 inch maximum lifts and lightly compacted.
2.Care should be taken by the contractor to avoid compaction of the native soils in
the trench areas. The base and side walls of trench excavations should be
scarified prior to sand and chamber installation.
3.Changes to this design should not be made without consultation and approval
by a representative of HP-Kumar.
APP52;IMATE SCALE
1 I1CH )EET
Ground Surface
Insulate lid with 2"
blue board
Backfill valve box to bottom
of cap with onsite soil
1.5" Sch. 40, 90° long-sweep
or two 45° elbows
1.5" Sch. 40,
threaded cap
Install 6" valve box at
ground surface
APPROXIMATE SCALE:
1 INCH = 2 FEET
Notes:
1.All piping, fittings and valves should be Sch. 40 P9C.
2.Install distribution line cleanouts at the end of each distribution line.