HomeMy WebLinkAboutOWTS Installation Observations 08.03.2026August 3, 2026
502 Main Street, Suite A3, Carbondale, CO 81623 970-704-0311
Leonard Olim
Big Lenny's Storage Rifle LLC,
5458 Mount Vernon Parkway
Atlanta, GA 30327 PO Box 2834
Angela Newman <newmanangela2015@gmail.com>
Leonard Olim <biglennyolim@gmail.com>
C/o Myrl Serra <5mconst.llc@gmail.com>
RE: As-Constructed Report, On -site Wastewater Treatment System (OWTS), Big Lenny's Storage Rifle
LLC, 184 Gas Court, Rifle , Garfield County, CO West Rifle Industrial Park Lot: 4
SE Job No. 36016.01 , Parcel N o: 217718201004 . New Garfield County Permit # SEPT-9731
Dear Leonard, Angela and Myrl:
Pursuant to County requirements, this letter provides documentation that the Onsite Wastewater Treatment
System (OWTS), recently installed at the above referenced site, is in compliance with the permitted
design. Sopris Engineering inspected the excavations, soils, materials and the installation of the system
components during construction, prior to final backfill and after all installations were completed. The
septic tank, soil treatment area (STA) and distribution component installations were designed and
constructed to serve the limited 270 gpd usage on the subject property.
Sopris Engineering performed site visits to inspect and document the as-constructed conditions of the
OWTS. Inspections were coordinated with the general contractor, Myrl Serra, 5m Construction that
installed the system components. The as-constructed conditions and installation of the OWTS components,
under Garfield County EHD Permit # SEPT-9731, is in compliance with Garfield County regulations. The
installed system components, design specifications and details are delineated on the attached As-
Constructed plan, C1-OWTS Record Drawing, dated 08-03-2026, by Sopris Engineering.
As-Constructed OWTS Conditions and Design Criteria
Installed OWTS System
The system was constructed to provide for demand dosing of septic tank effluent to an engineered soil
treatment area (STA). The OWTS includes a gravity service pipe from the commercial shop facilities
building to a newly installed deep bury reinforced 1000-gallon concrete septic tank equipped with an
Orenco System bio tube high head effluent pump assembly for pressure distribution of septic tank effluent
to a new pressure dosed chamber trench system . The effluent discharge transport pipe was installed to
connect to a pressurized manifold connecting to the custom perforated distribution laterals at the proximal
end of each chamber trench. Each chamber trench has specified inspection ports and flush assemblies
appurtenances.
An Orenco Systems S-1 Simples CT ETM control panel was installed on struts at the SE corner of the
septic/dosing tank. The electric supply to the control panel was installed from a J-box at the SE corner of
the building. Pump and control wires from panel to components, routed to the dosing tank riser external
splice box are connected with silicon wire nuts.
OWTS As-Constructed Conditions Report
184 Gas Court, Rifle, Garfield County
Permit SEPT-9731, SE Job No. 3 6016 .01
August 3, 2026
Page 2
Final Inspection, System Testing and Startup
Sopris Engineering performed a site visit on June 23, 2026, to inspect and check operational function of
the recently installed OWTS components . SE inspected the OWTS to complete the required As -
Constructed documentation for the record drawing, certification letter and to document that all previously
listed Final Inspection Punch list items were addressed pursuant to the email by Garfield County, Julia
Lee, dated 06-09-2026.
The floats were manually operated to test the pumps on/off /alarm activation and to confirm that the high
water visual/audible alarm is active. A squirt test was performed by observing the effluent height from an
orifice in threaded caps at all 3 distal end flush assemblies. The residual head squirt height was measured
at 4.0’ (48”) from the level of the distribution laterals set at the absorptive surface in the trenches. The
testing verified that the system is functioning as designed and can be set for automatic normal operation.
Design Calculations OWTS
The design flow was calculated as follows for a commercial shop/office facility onsite wastewater
treatment system (OWTS). The treatment capacity was designed for an equivalent 9 shop/office facilities
with an assumed 2 employees each. Minimum population based on 9 offices = 18 staff employees.
Gallons per day per person =15 gal/employee/day,
Max. Design flow (Qd)gallons/day = (# of people) x (avg. flow)gal/person/day.
Design flow Qd = 18*15 = 270 gpd
Septic Tank Design: 2-Day detention time = 270 x 2 = 540 gallons required.
Installed a 1000-gallon, two compartment concrete septic tank with an inlet sanitary tee and biotube
effluent filter with a high head pump assembly in the second chamber. Effluent filter handle was raised
within 6" of access riser lid. The tank was installed with ribbed PVC risers and fiber lids set to
approximately 9" above the finish grade surface.
Sub Surface Conditions and Testing:
A subsurface soil investigation and site assessment was performed by Sopris Engineering in on February
13, 2026. The soils were sampled and characterized by application of the USDA visual/tactile soil texture
method analysis from samples in two profile pits. Two excavated profile pits 1 & 2 were observed in the
East central portion of the site adjacent to the proposed soil treatment area field location. The soils below 4
to 9 inches of mixed surface fill & gravels consist of medium dense sandy clay loam with moderate
granular to slightly blocky structure with some cobbles and gravels to depths of 1.5 to 2.0 feet underlain by
dense slightly sandy clay loam with less than 5% of total rock content to the 8-foot depth explored in both
pits. The soil appears to be generally consistent across the site. No evidence of seasonal high ground water,
redox conditions or any other limiting conditions were observed in the profile pits. Groundwater levels are
expected to be below 20 feet from the existing surface grades on the relatively flat terrain. The soils are
suitable for a shallow conventional absorption field consisting of gravelless infiltration chamber units.
OWTS As-Constructed Conditions Report
184 Gas Court, Rifle, Garfield County
Permit SEPT-9731, SE Job No. 3 6016 .01
August 3, 2026
Page 3
Profile Pit-1
The soils below approximately 4 inches of surface gravels consist of moderately dense sandy clay loam
texture fill material with gravels and cobbles that has blocky to granular shape of moderate structural grade
to a depth of 2-feet contai ning approximately 40% total rock content. Soils below 2 feet underlying the
mixed fill consist of dense slightly sandy clay loam texture soil that has granular to massive structure of
weak structural grade with less than 5% of total rock content to the 8-foot depth explored. The soils are
characterized as a soil type 3A Sandy clay loam.
Profile Pit-2
The soils below approximately 3 inches of surface gravels consist of moderately dense sandy clay loam
texture fill material with gravels and cobbles that has blocky to granular shape of moderate structural grade
to a depth of 1-foot containing approximately 40% total rock content. Soils below 1.5 feet underlying the
mixed fill consist of dense slightly sandy clay loam texture soil that has granular to massive structure of
weak structural grade with less than 5% of total rock content to the 8-foot depth explored. The soils are
characterized as a soil type 3A Sandy clay loam.
The native soils sampled from 2-4 feet below the surface, in both profile pits, are characterized as a soil
type 3A soil type consisting of slightly sandy clay loam texture soil with granular to massive structure of
weak structural grade. The tan to grayish sandy clay loam soil tactile test ribbons were 1 ¾-inch long. Soil
type 3A has an effective loading rate for conventional soil treatment of 0.30 gal/S.F./day for a level 1
conventional treatment system.
Soil Treatment Area System Design
The soil treatment area (STA) was designed based on utilizing the effective Long Term Acceptance Rate
(LTAR) for native soils and the application of appropriate loading factors for a treatment level-1 system
utilizing pressure dosed chamber trenches with custom perforated distrib ution laterals.
Long Term Acceptance Rate (LTAR)
Maximum hydraulic loading rate for TL1 effluent is 0.3 gal./S.F./day) for the Type 3A receiving soil.
A(sf) = Qd x L.F.1 x L.F.2 .: A = Area;
LTAR LTAR = 0.3 gal/S.F./day for sandy clay loam massive
Qd = flow (gal/day) for OWTS = 270 gpd
L.F.1=0.8 pressure dosed trench application
L.F.2=0.7 gravelless chambers
STA Sizing: A(sf) = 270 gpd x 0.8 x 0.7 = 504 S.F.
0.3 Gal/S.F./day
Number of Quick -4 Infiltrator chambers 4'x3'x12"chambers:
504 S.F = 41 Infiltrator Quick-4 chambers; Use 42 chambers
12 S.F./Chamber
OWTS As-Constructed Conditions Report
184 Gas Court, Rifle, Garfield County
Permit SEPT-9731, SE Job No. 3 6016 .01
August 3, 2026
Page 4
Installed 42 Quick-4 Infiltrator chambers in 3 trenches 58' long by 3' wide with 14 chamber units per
trench plus two end caps as delineated on the plan.
Effluent Distribution System
The septic tank effluent is pressure discharged to a common manifold pipe, install ed at the head of the
trenches, via a 2” transport pipe from the high head pump discharge assembly in a biotube filter vault set in
the second compartment of the 1,000-gallon tank. The minimum slope of the transport pipe from the tank's
dosing compartment to the manifold was installed at a minimum 2% slope to allow for drain back to the
tank.
The distribution system was installed for effluent to be equally distributed across the absorptive surface in
each trench via individual custom perforated pressure distribution laterals connected to the manifold pipe.
The distribution laterals were installed on the infiltrative surface, under the chambers, along the entire
length of each trench. The 5/32-inch orifices were drilled on 2’ centers oriented upward along the length of
the distribution lateral except for the first and last orifices oriented downward to allow for drainage. A ball
valve was installed on the terminal end of each distribution lateral extended vertically adjacent to the 4”
inspection port from the distal end cap , housed in a 10" valve box with lid set 2" above surface grades.
OWTS Operation and Maintenance
The floats were set pursuant the original design intent performance specifications with respect to the
dosing tank, piping and STA configuration as -constructed conditions. The performance calculations are
presented on the Record drawing. The dosing volume is approximately 51 gallons per cycle.
All components of the engineered OWTS shall be inspected on a regular basis and be properly maintained.
The responsibility for repair and maintenance of the system will remain with the property Owner. The
owner shall retain the services of qualified personnel to inspect the OWTS and to perform all maintenance
and repairs necessary to ensure that the system is in good operating condition and is in compliance with the
manufacturer’s performance requirements. The operating components of the OWTS should be inspected
every six months by the owner or qualified service provider. In general, for a properly utilized system,
septic tanks should be pumped every 3-5 years. The effluent filter should be cleaned every six months and
at the time of pumping. Absorption fields should be maintained with suitable vegetative cover and kept
free of root invasive plants. Positive s urface drainage away from the absorption field should be maintained.
If you have any questions or need any additional information, please call.
Sincerely,
SOPRIS ENGINEERING, LLC
Paul E. Rutledge Yancy Nichol, PE
Design Engineer Principal
8/3/2026