HomeMy WebLinkAboutOWTS Installation Observation 09.30.25CBO Inc.
129 Cains Lane
Carbondale, CO 81623
970.309.5259
carla.ostberg@gmail.com
September 30, 2025 Project No. C1959
Dan Richardson
dan@boldepp.com
Onsite Wastewater Treatment System (OWTS) Installation Observations
116 Crystal River Road
Garfield County, Colorado
Permit SEPT-9281
Dan,
CBO Inc. observed the installation of the onsite wastewater treatment system (OWTS) on September 25,
2025 and September 29, 2025 for the subject property. Alpine Excavation and Land Clearing installed the
system.
The OWTS design is based on 4-bedrooms. An average daily wastewater flow of 525 GPD was used.
The existing septic tank was abandoned by crushing it and filling the void. The existing soil treatment
area (STA) was abandoned in place and any distribution piping was removed where the new STA was
installed.
The new 4-inch SDR-35 sewer line exiting the residence had a double-sweep clean out and a minimum
2% grade to the septic tank. The sewer line connects to the existing cast iron sewer line with a Fernco
as close to the foundation as feasible.
The system installation included a 1500-gallon, two-compartment Infiltrator® poly septic tank with an
Orenco® Biotube Effluent filter followed by a 500-gallon, single-compartment Infiltrator® poly pump
chamber with an Orenco® Biotube Pump Vault and an Orenco® PF3005 pump. These filters must be
cleaned annually, or as needed. The septic tanks are anchored with Deadmen. Anchoring was
implemented as a preventative measure and not required based on the height of the groundwater in the area
of the septic tanks being less than 36-inches from the bottom of the septic tank and depth of cover over the
septic tanks at approximately 2-feet. The floats are set to dose 65 gallons each pump cycle. The control
panel for the pump is located within line of sight of the septic tank. Start up was performed by Valley Precast
out of Buena Vista.
Effluent is pressure dosed through a 1.5-inch diameter pump line to a 13’ x 50.5’ mounded, unlined sand
filter. The excavation for the sand filter begins 1.0-foot below native grade. Two-feet of sand filter material
was installed in the over-excavated footprint, resulting in 1-foot of sand filter material extending above native
grade.
Effluent is pumped through a 1.5-inch diameter pump line from the pump chamber to an Orenco®
automatic distributing valve (ADV), model 6402. The ADV was placed at a high point in an insulated riser
with access from grade.
Laterals are 1.5-inches in diameter with 5/32-inch diameter orifices facing down, spaced 3.0-feet on
center, installed on the GeoMat™ with the filter fabric over the laterals. Four 39” wide GeoMat™ sheets are
placed on the 13-foot wide bed. Each 1.5-inch diameter lateral ends in a sweeping ell facing up with a ball
valve for flushing. Inspection ports were installed at each corner of the bed.
The OWTS was generally installed according to specifications. This observation is not a guarantee of
workmanship and/or parts and materials. CBO Inc. should be notified if changes are made to the OWTS
in the future. Any additional OWTS construction must be according to the county regulations.
LIMITS: Observations are limited to components that are visible at the time of the inspection. The installer must
have documented and demonstrated knowledge of the requirements and regulations of the county in
which they are working. The quality of the installation is dependent on the expertise of the installer, soil
type, and weather conditions.
Please call with questions.
Sincerely,
CBO Inc.
Carla Ostberg, MPH, REHS
-
Garfield County Public Health
2014 Blake Ave.
Glenwood Springs, CO 81601
Phone: (970) 945-6614 ext. 8150
For inspections, call: 970-945-6614 ext. 8150 and call the Design Engineer, if applicable
Project Address: 116 Crystal River Road, Carbondale Parcel No.: _239333409001
Owner Name: Owl Moon LLC Owner Phone: (239) 379-3414
Designed By: CBO Inc. Designer Phone: (970) 309-5259
Number of Bedrooms: _4_Minimum Tank Capacity: 1,250-gallon Minimum Absorption: 656.25 ft2
OWTS PERMIT
KEEP AVAILABLE AT PROJECT SITE
Permit Number _SEPT-9281______________________________
Permit Type X New X Repair X Remodel/addition X Tank only
Issue Date _06/13/2025____________________ Expiration Date_06/13/2026_________________
Permit Conditions:
This OWTS Permit is approved on the condition of compliance with the report and design as submitted by CBO Inc. dated May
15, 2025. Changes to the design and permit must be approved by Garfield County Public Health and the designer prior to
construction.
Prior to installation of OWTS components, the soils in the proposed STA must be confirmed by the designer and a report of
the soil conditions shall be provided to GCPH. The new OWTS will serve an existing four-bedroom residence. The new OWTS
components will consist of a new 1,500-gallon two compartment septic tank on the CDPHE approved list, set level with access
to grade and equipped with an effluent filter in the outlet tee. Effluent will flow from the septic tank to a 500-gallon single
compartment pump chamber which will house a new screened high-head pump. The septic tank and pump chamber will be
anchored according to manufacturer recommendations due to the presence of high ground water. Effluent will be dosed
from the pump chamber to an automatic distributing valve set at the high point of the system that will distribute effluent to
656.5 ft2 of STA. The new STA will consist of a 13 ft by 50.5 ft unlined sand filter bed, consisting of at least 2 feet of secondary
sand media overlain by perforated distribution laterals placed in GeoMat distribution media. Distribution laterals are to be 1 ½
inch Schedule 40 PVC, with 5/32-inch orifices every 3-feet on center facing downwards with orifice shields. Each lateral is to
end in a flushing valve at the distal end. The residual head (squirt height) at the end of the system is to be 5-feet. The lower
infiltrative surface shall be at 1-foot below grade and final cover will be mounded to reach approximately 1.5ft of soil over
the distribution laterals and sloped at a 3:1 ratio to the native grade. Inspection ports are to be installed at each corner of the
bed. Maintain all setbacks and elevations as designed. The existing tank and pump chamber must be abandoned per Garfield
County OWTS Regulations by crushing or removal.
To assist in scheduling, please contact Garfield County Public Health (970-945-6614 ext. 8150) to notify the start of OWTS
construction. Contact the designer and Garfield County Public Health at least 48 hours prior to requesting final inspection of the
installed system prior to backfill. NO OWTS COMPONENT SHALL BE BACKFILLED WITHOUT PRIOR APPROVAL FROM GARFIELD
COUNTY PUBLIC HEALTH AND THE DESIGNER.
Agreement
All installations must comply with all requirements of the Garfield County OWTS regulations
including but not limited to the conditions specified above.
In consideration of the issuance of the permit, the applicant hereby agrees to comply with all
laws and regulations related to the zoning, location, construction, and erection of the proposed
OWTS and associated structures for which this permit is granted. The applicant further agrees
that if the above said regulations are not fully complied with in the zoning, location, erection,
and construction of the above described OWTS and structure, the permit may then be revoked
by notice from the Health Department and immediately become null and void.
The issuance of a permit and specifications of terms and conditions therein will not constitute
assumption of liability, nor create presumption that the local public health agency or its
employees may be liable for the failure or malfunctioning of any system. Permit issuance will
not constitute a certification that the system, the equipment used in the system, or any
component used for system operation will ensure continuous compliance with the provision of
the OWTS Act, the regulations adopted thereunder, or any terms and conditions of a permit.
Permit Approval
Plans and specifications for the proposed OWTS have been reviewed and are considered
satisfactory. Permission is hereby given to the property owner(s) to perform the work indicated
in accordance with the Garfield County OWTS Regulation. This Permit will expire 1 year from
the date of issuance unless construction on the system has commenced. An "as-built" drawing
must be submitted and inspection of the system must be completed by GCPH before final
approval of the system will be issued.
06/13/2025
Issued By: Garfield County Environmental Health
Department
Date
infiltratorwater.com • (800) 221-4436
Buoyancy Control Guidance
July 2023Infiltrator Tanks
Before you Begin
This guidance document presents a method for assessing buoyancy control needs for Infiltrator Water Technologies Infiltrator tanks. Tank
buoyancy control measures must be implemented according to state and/or local regulations and approvals, which may supersede these
guidelines. If unsure of the requirements for a particular site, contact the state or local health department or permitting authority.
If tank buoyancy control measures are implemented, refer to Infiltrator Tank General Installation Instructions and Riser Connection Guidance
documents, as applicable, for completing the installation. This guidance document is not a tank installation instruction document.
How to Use this Document
1. Using Step 1, Table 1, and Figures 1 and 2, verify that the level of subsurface water
is below the height of the outlet pipe saddle and determine if buoyancy control is
required. See page 2 notes on terminology.
2. Use the appropriate row in Step 2, Table 2 to determine the minimum buoyancy
control methods for the site conditions.
3. Once the preferred buoyancy control method is selected, follow the
implementation procedures provided in Step 3.
Step 1 – Determine Need for Buoyancy Control
Required information: (1) maximum height of subsurface water above the tank
bottom; and (2) the depth of soil cover above the tank top. Tank buoyancy control
may be required if:
• the level of subsurface water outside the tank has the potential to rise 30 inches
(750 mm) or more above the bottom of the tank; and
• less than 12 inches (300 mm) of soil cover is to be placed as backfill over the tank
top.
[
FOR ALL TANK MODELS, NO BUOYANCY CONTROL IS REQUIRED IF THERE ARE
AT LEAST 12 INCHES (300 MM) OF SOIL COVER ABOVE THE TANK TOP.
FOR THE IM-300, NO BUOYANCY CONTROL IS REQUIRED IF THERE ARE AT
LEAST 6 INCHES (150 MM) OF SOIL COVER ABOVE THE TANK TOP.
Table 1 Instructions
1. In the left-hand column of Table 1, locate the row corresponding to the height
of the subsurface water elevation outside the tank and above the tank bottom
(Parameter I) for the site conditions. See Figure 2.
2. Follow that row to the right until reaching the column corresponding to the depth
of soil cover above the tank top (Parameter II). See Figure 2.
3. If the tank model is listed in that cell, then buoyancy control is required, proceed
to Step 2. If the tank model is not listed in that cell, then no buoyancy control is
required.
4. Infiltrator tanks shall not be installed where the subsurface water level outside
the tank exceeds the height of the outlet pipe saddle. See Figure 1 and Table 1,
Note 4 for outlet pipe saddle information.
Notes:
1. Infiltrator tank models include: IM-300, IM-540, IM-1060, CM-1060, IM-1250, and
IM-1530.
2. Minimum 6 inches (150 mm) soil cover backfill is required.
3. Infiltrator tanks shall not be installed where the subsurface water level outside the
tank exceeds the height of the outlet pipe saddle.
See Figure 1.
4. The height of the outlet pipe saddle for the IM-540, IM-1060, CM-1060, IM-1250, and
IM-1530 is 43 in (1,075 mm). The height of the outlet pipe saddle for the IM-300 is
40.75 in (1,035 mm).
5. For Indiana installations, if the depth of uninterrupted
saturated soil conditions cannot be determined
from the site soil evaluation report or other
site-related data and other information
indicates the possible presence of
a perched ground water table,
no buoyancy controls are
required. See page 2
note on terminology.
Table 1: Infiltrator Tank Models1 and Conditions Requiring Buoyancy Control
Parameter I:
Subsurface water height
above tank bottom
Parameter II:
Soil cover depth above tank top2
A B
6 in (150 mm) up to
12 in (300 mm)
12 in (300 mm)
or greater
1 Above outlet pipe saddle4
(greater than 43” [1,075 mm]Do not install tank Do not install tank
2 36” (900 mm) to 43” (1,075 mm)4
(to outlet pipe saddle)
All models
except IM-300 Not Required
3 30” (750 mm) to 36” (900 mm) IM-1530 Not Required
4 Less than 30” (750 mm)Not Required Not Required
Figure 1: Limitations When Subsurface Water is Present Above Tank Bottom
Figure 2: Buoyancy Control Parameters for Table 1Depth of Soil Cover Above Tank Top
Tank Top
Tank Bottom
6" (150 mm) min.
48" (1,200 mm) max.
Outlet Pipe
Saddle:
Maximum
Allowable
Subsurface
Water
Elevation
Maximum Subsurface
Water Condition
Above Tank Bottom 1
Do Not
Install
Allowable
Tank Bottom
Tank Top
Parameter II
Depth of Soil Cover
Above Tank Top
Parameter IPosition ofMaximumSubsurfaceWater ConditionAbove Tank Bottom
Depth of Soil Cover Above Tank Top
Tank Top
Tank Bottom
6" (150 mm) min.
48" (1,200 mm) max.
Outlet Pipe
Saddle:
Maximum
Allowable
Subsurface
Water
Elevation
Maximum Subsurface
Water Condition
Above Tank Bottom 1
Do Not
Install
Allowable
Tank Bottom
Tank Top
Parameter II
Depth of Soil Cover
Above Tank Top
Parameter IPosition ofMaximumSubsurfaceWater ConditionAbove Tank Bottom
Table 2: Buoyancy Control Method Selection
Tank Model
Parameter 1:Position of subsurface water above tank bottom
Parameter 2:Soil cover depth above tank top
Buoyancy Control Methods1
Minimum supplemental downward force required3
(total, both tank sides)
Wood Beam Anchor Ballast Options (min. length/side)Concrete Beam Anchor Ballast Options (min. length/side)Precast concrete plates (min. no./side)
Helical anchors2 (min. no./side)
Anchor-lock system2
(min. no./side)
Concrete collar (min. width x min. height)1
6”x6” beam
2
6”x6” beam with cross-members
3
6”x6” beamside-by-side
1
6” wide
2
8” wide
3
12” wide
IM-540 36 in (900 mm) to
outlet pipe saddle4 6 in (150 mm) to
12 in (300 mm)
3.8 ft
(1.2 m)
3.8 ft
(1.2 m)
3.8 ft
(1.2 m)
3.8 ft
(1.2 m)
3.8 ft
(1.2 m)
3.8 ft
(1.2 m)2 2 2 6 in (150 mm)
x 9 in (225 mm)
1,000 lbs
(450 kg)
IM-1060 36 in (900 mm) to
outlet pipe saddle4 6 in (150 mm) to
12 in (300 mm)
7.5 ft
(2.3 m)
6.0 ft
(1.8 m)
5.5 ft
(1.7 m)
7.5 ft
(2.3 m)
6.5 ft
(2.0 m)
5.0 ft
(1.5 m)2 2 2 6 in (150 mm)
x 9 in (225 mm)
3,550 lbs
(1,620 kg)
CM-1060 36 in (900 mm) to
outlet pipe saddle4 6 in (150 mm) to
12 in (300 mm)
4.8 ft
(1.5 m)
4.8 ft
(1.5 m)
4.8 ft
(1.5 m)
6.3 ft
(1.9 m)
5.5 ft
(1.7 m)
4.8 ft
(1.5 m)2 2 2 6 in (150 mm)
x 9 in (225 mm)
2,200 lbs
(1,000 kg)
IM-1250 30 in (750 m) to outlet
pipe saddle4 6 in (150 mm) to
12 in (300 mm)6.3 ft (1.9 m)6.3 ft (1.9 m)6.3 ft (1.9 m)6.3 ft (1.9 m)6.3 ft (1.9 m)6.3 ft (1.9 m)2 2 2 6 in (150 mm) X 9 in
(225 mm)3,300 lbs
IM-1530 30 in (750 mm) to
outlet pipe saddle3 6 in (150 mm) to
12 in (300 mm)
Use
alternate
method
(1,500 kg)9.5 ft
(2.9 m)
Use alternate
method
Use alternate
method
Use alternate
method 2 2 2 9 in (225 mm)
x 9 in (225 mm)
6,200 lbs
(2,820 kg)
Notes:
1. See method-specific technical specifications and installation instructions below.
2. See manufacturer-specific information below.
3. Supplemental downward force is provided for custom-designed anchor ballast systems. See discussion below.
4. The height of the outlet pipe saddle for the IM-540, IM-1060, CM-1060, IM-1250, and IM-1530 is 43 in (1,075 mm).
5. For the IM-300, no buoyancy control is required if there are at least 6 inches (150 mm) of soil cover above the tank top.
Installation Terminology Notes:
1. “Subsurface water” refers to a water-saturated zone of soil. Do not install if subsurface water is continuous from the tank bottom elevation to any point above the outlet
pipe saddle elevation.
2. “Uninterrupted saturated soil” refers to water-saturated soil with no gaps in the saturated condition. An example of a gap in the saturated condition is a perched water
table, when two water-saturated soil zones are interrupted by an unsaturated soil zone. Do not install if uninterrupted saturated soil is present from the tank bottom
elevation to any point above the outlet pipe saddle elevation.
3. A perched water table is allowable above the outlet pipe saddle elevation only if unsaturated soil is present between the perched water table zone and tank bottom
elevation.
Step 2 – Determine Buoyancy Control Method
Step 2 is used if the Step 1 analysis shows that buoyancy control is required for the tank model and installation conditions. The site-specific maximum height of subsurface
water outside of the tank and above the tank bottom and the depth of soil cover above the tank top must be known to complete Step 2.
Table 2 Instructions
For the appropriate tank model, select the desired buoyancy control method under each method description column. Refer to Step 3 – Implementation and Supplemental
Step 3 – Implementation
Effective buoyancy control requires careful preparation, proper excavation, precise
placement, secure strapping and proper backfilling, as described and illustrated
in Step 3 below and the Infiltrator Tank Installation Instructions. Step 3 includes
specifications and system installation guidance for five buoyancy control system
categories.
• 3-1: Beam Anchor Ballast
• 3-2: Precast Concrete Plate Anchor Ballast
• 3-3: Helical Anchors and Anchor-Lock Assemblies
• 3-4: Concrete Collar Anchor Ballast
• 3-5: Custom-Designed Buoyancy Controls
Following Step 3, supplemental technical guidance is provided for use with these
buoyancy control methods. See the Supplemental Technical Guidance section for
strap information as well. Straps meeting the appropriate are available from IWT
(TANK-BCS-KIT). This guidance document is not a tank installation instruction
document. Refer to the Infiltrator Tank Installation Instructions for complete
information on tank installation requirements.
Step 3-1: Beam Anchor Ballast
The beam anchor ballast options shown in Table 2 include the installation of wood
or concrete beams adjacent to the tank, connected with two straps positioned
across the top of the tank. The beam anchor ballast option allows the installer to
select either beam construction material. The beam options resist tank buoyant
forces using the weight of the soil column over the beam anchor ballast to
counteract uplift. Therefore, it is critical that the widest dimension of the beam
be placed horizontally on the base of the tank excavation, running parallel with
the length of the tank. Beam construction materials shall meet the following
specifications:
• Pressure-treated lumber shall be American Wood Protection Association (AWPA)
Use Category UC4B, UC4C, UC5B, or UC5C.
• Concrete parking bumpers (also referred to as wheel stops) shall be steel-
reinforced concrete with dimensions of 6-, 8-, or 12-inches wide by 6 inches high
(150 mm, 200 mm, or 300 mm wide x 150 mm high).
• Fasteners shall be hot-dipped galvanized steel or stainless steel.
WARNING: Infiltrator does not recommend the use of beams fabricated
using thermoplastics, including, but not limited to, chambers, pipe,
decking, and parking bumpers.
2 Contact Infiltrator Water Technologies at (800) 221-4436 or info@infiltratorwater.com for additional information.
Wood Beams
The wood beam anchor ballast can be configured three ways, depending on
material and space availability:
• Wood Beam Option 1: Pressure-treated 6” x 6” – This option includes a single 6”
x 6” beam connected to straps on each side of the tank (Figure 3).
Figure 3: Wood Beam Option 1
• Wood Beam Option 2: Pressure-treated 6” x 6” with cross-members – This option
includes a single 6” x 6” beam on each side of the tank equipped with a series of
pressure-treated wood cross-members to increase the surface area of the beam,
connected to straps (Figure 4). Cross-members shall be 2” x 8” x 18” connected
to the beam with four screws per member and distributed uniformly along the
long axis of the beam. Cross member placement must not interfere with the strap
locations.
Figure 4: Wood Beam Option 2
• Wood Beam Option 3: Pressure-treated 6” x 6” members placed side-by-side –
This option includes two 6”x6” beams placed side by side and connected to looped
straps on each side of the tank (Figure 5). The beams shall be connected using
two 2” x 6” members screwed to the top and bottom of the side-by-side beams in
two locations near the ends of the beams. Fasteners shall be 3.5-in screws with
washers.
Figure 5: Wood Beam Option 3
Concrete Beams
The concrete beam can be configured three ways, depending on material and
space availability, using parking bumpers (also referred to as wheel stops). This
option includes a single concrete beam connected to straps on each side of the
tank (Figures 6 and 7). Three concrete beam anchor ballast options are available,
depending upon the parking bumper width as follows:
• Option 1: 6-in-wide precast concrete parking bumper
• Option 2: 8-in-wide precast concrete parking bumper
• Option 3: 12-in-wide precast concrete parking bumper
Note that the Concrete Beam Option is not recommended for use with the IM-1530
tank due to limitations in availability of parking bumpers that would be long
enough to provide adequate resisting force. Use an alternative buoyancy control
method for the IM-1530.
Figure 6: Concrete Beam Parking Bumpers
Figure 7: Concrete Beam
Table 2 provides the minimum length of beam
required for the tank model and installation
conditions. A minimum 1.5 factor of safety has been
applied to determine the minimum required beam
length.
Wood and concrete beam installation should be
as described below. See Ratchet Strap Material
Specifications section below for additional
information.
1. Determine the minimum beam length from Table
2.
2. Place beams on the excavation bottom, such
that the beam and tank bottoms are at the same
elevation. The beam must be oriented with the
widest dimension placed horizontally.
3. Position beams parallel to the long axis of the
tank.
4. Position beams to be centered between strap
locations and extend at least 6 in beyond the strap
locations.
5. Position the beam a minimum of 6 in (150 mm)
from the outermost footprint of the tank to allow
connection of the strap system and placement and
compaction of soil backfill below the tank haunches.
WARNING: Never place any portion of
the anchor ballasts beneath the outermost
footprint of the tank, including beneath the
haunches.
2, 3, 52, 3, 5
Position beam and tank.
44
Position strap on beam.
Contact Infiltrator Water Technologies at (800) 221-4436 or info@infiltratorwater.com for additional information. 3
WARNING: Do Not Use Cable Tie-Downs: The use of cables to connect
anchor ballasts in lieu of strapping is prohibited. Cables concentrate the
load exerted by the buoyancy control system within a small area on the
tank surface, resulting in the potential to damage the tank.
6. Position the 14-ft-long (4.3 m) strap across
the top of the tank at the locations embossed
for strap placement (Figure 10).
7. At each beam connection point, wrap
the 5-ft-long (1.5 m) looped-end strap to
the beam at points aligning with the straps
placed across the top of the tank. If the beam
includes cross-members, position to prevent
interference between looped-end straps and
cross-members.
8. Connect the hooked end of the 14-ft-long
(4.3 m) strap to the two looped ends of the
5-ft-long (1.5 m) looped-end strap.
9. Connect the non-hooked end of the
14-ft-long (4.3 m) strap to the ratchet.
10. Connect the hooked end of the ratchet strap
to the 5-ft-long (1.5 m) looped-end straps, such
that the ratchet is positioned below the mid-
seam elevation of the tank. Do not allow the
ratchet to be in contact with the tank.
11. Remove slack in the straps through a
combination of beam positioning and the
ratchet, such that the ratchet is positioned
below the mid-seam elevation of the tank and
not contacting the tank. Maintain the minimum
6-in (150 mm) spacing between the edge of
tank and beam.
12. Place and compact backfill beneath the tank haunches and around and above
the beams to an elevation 6 inches (150 mm) above the top of the beams. Place
and compact backfill as described in the Infiltrator Tank Installation Instructions.
13. With the anchor ballasts stabilized by 6 inches (150 mm) of compacted backfill,
tension the strap to eliminate all slack using the ratchet. The tension should make
the strap tight, without displacing the beams or damaging the tank.
14. Do not over tighten the straps.
15. Complete backfilling the tank as described in the Infiltrator Tank Installation
Instructions.
Step 3-2: Precast Concrete Plate Anchor Ballast
The precast concrete plate anchor ballast option shown in Table 2 includes the
installation of four individual concrete anchor ballasts, connected with straps
positioned across the top of the tank. Historically, precast concrete plate anchors
have been spare concrete septic tank lids repurposed as anchor ballasts, but they
can be fabricated specifically as anchor ballasts as well. The precast concrete plate
anchor ballast option allows the installer to select plate size and shape, provided
that each plate provides a minimum 4 ft2 (0.37 m2) of horizontal area and minimum
3-in thickness (75 mm). The precast concrete plate anchor ballast options resist
tank buoyancy forces using the weight of the soil column over the plate anchor
ballast to counteract uplift. Therefore, it is critical that the widest dimension of the
plate anchor ballast be placed horizontally on the base of the tank excavation.
Plate construction material shall be precast concrete having a minimum 3,500 psi
(24.1 MPa) compressive strength at 28 days and minimum 6% air entrainment.
Connectors protruding from the anchor plate and used for strap connection shall
be steel reinforcing bar, galvanized steel, or stainless steel capable of supporting a
2,500-lb (1,134 kg) tensile force. Do not use plastic connectors.
WARNING: Infiltrator does not recommend the use of plate anchor
ballasts fabricated using materials other than concrete.
The precast concrete plate anchor ballast can be configured using a square,
rectangular, or circular shape. For rectangular-shaped anchor ballasts, the long
axis of the plate shall be placed parallel with the long axis of the tank. Precast
concrete plate anchor ballast sizing and configuration options are shown in Table
3 and Figure 8.
Table 3: Precast Concrete Plate Anchor Ballast
Precast concrete plate
anchor ballast shape
Minimum horizontal dimensions
(minimum 3-in (75 mm) thickness)
Square 2 ft x 2 ft (0.61 m x 0.61 m)
Rectangular
Maintain a 1 ft (0.31 m) minimum width,
with length to provide a minimum 4 ft2
(0.37 m2 ) horizontal plate area per anchor
ballast
Circular 2.3 ft diameter (0.70 m diameter)
As shown in Table 2 and Figure 8, four precast concrete plate anchor ballasts are
required for all tank models. The minimum horizontal plate area specifications are
the same for all tank models. A minimum 1.5 factor of safety has been applied to
determine the minimum horizontal plate area.
Figure 8: Precast Concrete Plate Anchor Ballast Options
Precast concrete plate anchor ballast installation should be as described below.
See Ratchet Strap Material Specifications section below for additional information.
1. Use 4 precast concrete plate anchor ballasts per installed tank.
2. Place anchor ballasts on the excavation
bottom, such that the anchor ballast and tank
bottoms are at the same elevation. The precast
concrete plate anchor ballast must be oriented
with the widest dimension placed horizontally.
3. Position anchor ballasts to align with the
locations on the tank embossed for strap
placement (Figure 10).
4. Position the anchor ballasts a minimum of 6
in (150 mm) from the outermost footprint of the
tank to allow connection of the strap system and
placement and compaction of soil backfill below
the tank haunches.
WARNING: Never place any portion of
the anchor ballasts beneath the outermost
footprint of the tank, including beneath the haunches.
STRAPWIDTH
MINIMUM 3-IN. (75 mm)
THICK PLATE MAY BE
SQUARE, RECTANGLE,
OR CIRCLE WITH
MINIMUM 4 FT2 (0.37 m2)
HORIZONTAL AREA
STRAP WITH
RATCHET (TYP.)
66
Position straps on tank.
8, 108, 10
Connect straps to beam.
Remove strap slack.
10, 1110, 11
Position plate and tank.
2, 42, 4
4 Contact Infiltrator Water Technologies at (800) 221-4436 or info@infiltratorwater.com for additional information.
WARNING: Do Not Use Cable Tie-Downs: The use of cables to connect
anchor ballasts in lieu of strapping is prohibited. Cables concentrate the
load exerted by the buoyancy control system within a small area on the
tank surface, resulting in the potential to damage the tank. Cable may
damage the tank.
5. Position the 14-ft-long (4.3 m) straps across
the top of the tank at the locations embossed for
strap placement (Figure 10).
6. Connect the hooked end of the 14-ft-long
(4.3 m) strap to the concrete anchor ballast
hardware. Looped-end straps are not required
to connect to the anchor ballast hardware.
7. Connect the non-hooked end of the 14-ft-long
(4.3 m) strap to the ratchet.
8. Connect the hooked end of the ratchet
strap to the concrete anchor ballast hardware.
Looped-end straps are not required to connect
to the anchor ballast hardware.
9. Position the ratchet below the mid-seam
elevation of the tank. Do not allow the ratchet to
be in contact with the tank.
10. Remove slack in the straps through a
combination of anchor ballast positioning and
the ratchet.
11. Place and compact backfill beneath the tank
haunches and around and above the anchor
ballasts to a height of 6 in (150 mm)
above to top of the anchor ballast. Place and
compact backfill as described in the Infiltrator
Tank Installation Instructions.
12. With the anchor ballasts stabilized by 6 inches (150 mm) of compacted backfill,
tension the strap to eliminate all slack using the ratchet. The tension should make
the strap tight, without displacing the precast concrete plate anchor ballasts or
damaging the tank.
13. Do not over tighten the straps.
14. Complete backfilling the tank as described in the Infiltrator Tank Installation
Instructions.
Step 3-3: Helical Anchors and Anchor-Lock Assemblies
Helical anchors and anchor-lock assemblies may be installed
as buoyancy control systems. For both types of system
described below, refer to the equipment manufacturer’s
installation instructions for details on how to use and install
the specified products. For helical and anchor-lock systems
other than those described below, use Step 3-5: Custom-
Designed Buoyancy Controls and Table 2 to determine the
required pullout force per anchor and the manufacturer’s
literature to determine the required product model and
installation requirements.
• Chance™ No-Wrench Screw Anchors – The Chance helical
anchor shall have a 6-inch (150 mm) diameter helix, Class 7, or equal. These
anchors rely on the shear strength of the soil combined with the weight of the
soil above the anchor helix to provide holding strength. Proper installation is to 4
ft (1.2 m) below the bottom of the tank excavation and to within 5° of alignment
with the strap alignment. Helical anchors should be installed so that the eye loop
is level with the bottom of the tank excavation. Determine the proper locations
for anchor installation to ensure that tie-down straps will be aligned properly for
each tank model (Figure 10). Never place helical anchors beneath the outermost
footprint of the tank, including beneath the tank haunches. Follow the anchor
manufacturer installation and testing instructions.
• DuckBill® Anchor-Lock Assembly – DuckBill models are shown for each tank
model in Table 4 below. These anchors rely on the shear strength of the soil
combined with the weight of the soil above the anchor to provide holding
strength. Determine the proper locations for anchor installation to ensure that
tie-down straps will be aligned properly for each tank model (Figure 10). The
system installer shall determine the DuckBill assembly materials of manufacture
for the specified model. Polyester straps shall be connected to the DuckBill anchor
wire assembly such that the wire assembly is not in contact with the tank body.
Never place anchor-lock assemblies beneath the outermost footprint of the tank,
including beneath the tank haunches. Follow the anchor manufacturer installation
and testing instructions.
Table 4: Anchor-lock Assembly Specifications
Tank Model DuckBill Assembly
IM-540 Model 40
IM-1060 Model 68
CM-1060 Model 68
IM-1250 Model 68
IM-1530 Model 88
WARNING: Do Not Use Cable Tie-Downs: The use of cables to connect
anchor ballasts in lieu of strapping is prohibited. Cables concentrate the
load exerted by the buoyancy control system within a small area on the
tank surface, resulting in the potential to damage the tank. Cable may
damage the tank.
Step 3-4: Concrete Collar Anchor Ballast
The concrete-collar anchor ballast option includes a cast-in-place concrete ring
along the perimeter of the mid-height seam (Figure 9). Cast-in-place concrete shall
be a minimum 3,000 psi (20.7 MPa) compressive strength at 28 days and minimum
6% air entrainment. Concrete shall be cast in contact with the exterior surface of
the tank to allow interlock with sidewall ribs and the mid-height seam. Reinforcing
steel is not required, but may be added if desired. The concrete collar shall be
continuous around the entire tank perimeter.
Figure 9: Concrete Collar Anchor Ballast
Concrete collar anchor ballast installation should be as follows:
1. Backfill the tank to the mid-seam area in accordance with the Infiltrator Tank
Installation Instructions.
2. If reinforcing steel is being used, place reinforcing bars in the desired location.
3. Pour concrete in contact with the exterior surface of the tank to create an
interlocking connection with tank sidewall ribs and the mid-height flange.
4. Pour concrete such that the bottom of the collar is located at the top of the mid-
seam flange of the tank.
5. Pour concrete such that the collar width and height conform with Table 2
minimum dimensional specifications.
6. Allow sufficient curing of the concrete to prevent damage to the concrete collar
before completing the tank backfilling process.
7. Backfill in accordance with the Infiltrator Tank Installation Instructions.
5, 85, 8
88
8, 9, 108, 9, 10
Position straps on tank.
Connect strap to plate.
Remove strap slack.
Contact Infiltrator Water Technologies at (800) 221-4436 or info@infiltratorwater.com for additional information. 5
Step 3-5: Custom-Designed Buoyancy Controls
Table 2 includes a column listing minimum supplemental downward forces to allow
custom-designed buoyancy controls not described in this guidance document.
Possible custom-designed anchor ballasts include, but are not limited to, precast
and cast-in-place concrete blocks, traffic barriers, concrete-filled half pipe, and a
concrete slab. Note that the Table 2 values include a suggested 1.5 factor of safety
applied to the calculated minimum downward force required to restrain the tank
and assumes the subsurface water level is positioned at the outlet elevation for the
tank model.
Custom-designed buoyancy control methods must consider the effect of saturated
soil conditions on the tank and custom-designed buoyancy control mechanism.
As long as buoyancy control is provided that supplies the minimum downward
force listed in Table 2, the tank is calculated to be stable for the subsurface water
level outside the tank and above the tank bottom and corresponding soil cover
conditions.
All Infiltrator strapping, fastening, and anchor ballast positioning
recommendations and the Infiltrator Tank Installation Instructions apply for
custom-designed buoyancy control methods. Since custom-designed buoyancy
controls may rely on the weight of the anchor ballast, the weight of soil column
over the anchor ballast, a combination of anchor ballast and soil weight, or
anchor pullout resistance, anchor placement and installation must account for
its functional design. Never place any portion of the anchor ballasts beneath the
outermost footprint of the tank, including beneath the tank haunches. Design and
installation methods shall be determined by the installer.
Contact Infiltrator’s Technical Services Department with any questions regarding
supplemental downward force requirements.
WARNING: Do Not Use Geogrid-Based Buoyancy Controls
Some tank manufacturers endorse the use of buoyancy control systems
incorporating geogrid draped across the tank connected to an anchor
ballast system or anchored within soil around the tank. Infiltrator
has determined that the use of geogrid buoyancy control systems is
unacceptable with Infiltrator tanks. Infiltrator advises against the use of
geogrid-based tank restraint systems for Infiltrator tanks. The presence of
the geogrid across the tank top and sides prevents the proper placement
and compaction of soil between the tank-body corrugations and beneath
the tank haunches, as required per the Infiltrator Tank Installation
Instructions.
Supplemental Technical Guidance
Supplemental technical guidance is provided below for use with the five buoyancy
control methods described in Step 3.
Excavation Requirements
The excavation width should provide a minimum of 36 inches (900 mm) clearance
beyond the tank on all sides when utilizing buoyancy control. This will allow
sufficient space within the excavation to place anchoring equipment and fasten
strapping. The excavation should provide a minimum 48-inch (1,200 mm)
clearance beyond the tank when using helical- and anchor-lock-type anchors to
allow for sufficient space to properly install the anchoring system. The actual
excavation size shall be determined by the installer. Refer to Infiltrator Tank
Installation Instructions for additional excavation procedures.
WARNING: Never place any portion of the anchor ballasts beneath the
outermost footprint of the tank, including beneath the haunches.
Short And Long-Term Groundwater Control
It may be necessary to implement groundwater control measures during tank
installation. Maintain dry conditions by expanding the excavation to create a
short-term groundwater collection sump for temporary placement of a dewatering
pump if needed. Long-term groundwater control measures such as underdrains
and interceptor trenches may be sensible if the site is amenable to construction of
a control system and such systems are not prohibited by regulation or law, and the
tank location is not subject to flooding. Underdrains and groundwater interceptor
trenches may prevent the need for tank buoyancy control measures.
Ratchet Strap Material Specifications
The configuration and capacity of the four-strap Infiltrator Tank Buoyancy Control
Strap Assembly (TANK-BCS-KIT) is designed to be compatible with both the beam
and precast concrete plate buoyancy control options shown in Table 2. If using
a beam anchor ballast, all four straps are required to complete the installation.
If using a precast concrete plate anchor ballast, only the 14-ft-long (4.3 m) strap
with hooked end and ratchet strap with hooked end are required, with connection
directly to the precast concrete plate hardware, thereby eliminating the need for
the 5-ft-long (1.5 m) looped-end straps.
Off-the-shelf, commercially available strap systems can also be used for beam and
precast concrete plate buoyancy control options shown in Table 2. For the beam
anchor ballasts, a commercially available four-strap system (two hooked-end
straps, two looped-end straps) is recommended for connecting the anchor ballasts
to the tank. For the precast concrete plate anchor ballast, a commercially available
two-strap system (two hooked-end straps) is recommended for connecting the
anchor ballasts to the tank. The suggested strap configuration is as follows:
• Two 5-ft-long (1.5 m) straps with sewn, looped ends (applies to beam only)
• One 14-ft-long (4.3 m) strap with a hooked end
• One ratchet strap with hooked end
For commercially available strap systems, the recommended method of strap
tightening is a ratchet, which is used to remove all slack and slightly pre-load
the system. All connections, fittings, and hardware must be corrosion resistant
(stainless steel or galvanized) or coated with epoxy or other corrosion-resistant
materials to inhibit deterioration in the subsurface environment. If not using
stainless steel or galvanized components, apply a corrosion-resistant coating prior
to burial. The recommended strap and ratchet specifications for commercially
available strap system components are as follows:
• Strap width: 2 in (5 cm)
• Strap material: Polyester
• Strap minimum working load limit: 3,300 lbs (1,500 kg)
• Strap assembly break strength: 10,000 lbs (4,538 kg)
• Strap hooks: Stainless steel
• Strap tightening mechanism: Stainless steel ratchet
• Ratchet working capacity: 10,000 lbs (4,538 kg)
Strap materials and capacity are the same for helical anchors and anchor-lock
assemblies. The strap length and connection configuration and hardware may
differ depending upon the type of anchor ballast system being used.
6 Contact Infiltrator Water Technologies at (800) 221-4436 or info@infiltratorwater.com for additional information.
WARNING: Do Not Use Cable Tie-Downs: The use of cables to connect
anchor ballasts in lieu of strapping is prohibited. Cables concentrate the
load exerted by the buoyancy control system within a small area on the
tank surface, resulting in the potential to damage to the tank.
Ratchet Strap Placement
Proper installation of straps over the tank is critical for tank stability under
changing conditions both inside and outside the tank. Straps must be placed at
the specified strapping locations for each tank model, as illustrated in Figure 10.
Strapping locations are embossed on the exterior surface of the tank. Strapping
locations correspond to structurally reinforced areas of the tank body. Straps must
never be placed over access openings, lids, or inlet/outlet piping. The ratchet must
be positioned below the tank midseam so it is not in contact with the tank body.
Straps must be tightened with a ratchet to remove slack and slightly pre-load the
system, without displacing the connected anchor ballasts or damaging the tank.
Strapping Notes:
1. Beam anchor ballasts shall be centered across the straps. Concrete plate and
helical anchor and anchor-lock ballasts shall be aligned with the strap installation
location embossed on the tank exterior.
2. Beam anchor ballasts shall extend a minimum of 6 inches (150 mm) beyond the
maximum strap width.
3. When applicable in Table 2, the minimum beam anchor ballast length
corresponds to the tank model-specific strap width plus 12 inches (300 mm),
allowing for a minimum of 6 inches to beam length beyond the strap.
Figure 10: Strap Positioning
WARNING: Do Not Use Cable Tie-Downs: The use of cables to connect
anchor ballasts in lieu of strapping is prohibited. Cables concentrate the
load exerted by the buoyancy control system within a small area on the
tank surface, resulting in the potential to damage to the tank.
Backfilling
A critical aspect of tank installation is proper backfilling. At a minimum, compacted
soil must be present: 1) between the tank-body corrugations; 2) beneath the tank
haunches; and 3) around and above the anchor ballasts (Figure 11). Backfill shall
consist of compacted, suitable soil placed in lifts no greater than 12 inches (300
mm), as described in the Infiltrator Tank Installation Instructions.
Figure 11: Backfill Placement
WARNING: Use of Tank Installation Instructions: This guidance
document provides general statements on backfilling and tank installation
only. Refer to the Infiltrator Tank Installation Instructions for complete
tank installation requirements.
Note: Infiltrator tanks do not require filling with water prior to backfill placement.
Water filling and backfilling to the tank mid-height is required if the tank is left in
either an open or backfilled excavation that may fill with water from precipitation
or other sources.
Parts and Supplies
The parts and supplies necessary are to be purchased separately from the tank.
All parts and supplies are either commercially available or available through
Infiltrator’s network of tank distributors. Some parts may require fabrication on
site using common construction practices.
General Information
• Refer to the Infiltrator Tank Installation Instructions for complete information on
tank installation requirements. Failure to comply with installation instructions will
void the warranty.
• Prior to ground disturbance, check for subsurface obstructions and utilities in
conformance with applicable regulatory requirements.
• Excavation safety provisions shall conform to applicable government
regulations.
• Follow manufacturer instructions for all products and devices used for Infiltrator
tank buoyancy control.
• Buoyancy control methods described herein do not account for unanticipated
conditions such as surface flooding, temporary inundation or other natural
occurrences, unintended removal of cover fill over tank, etc.
• Buoyancy control methods described herein are recommendations only; consult
a professional engineer for customized designs, if desired.
Tank Model Strap Spacing (Dimension “X”)
IM-300 32 in (813 mm)
IM-540 33 in (838 mm)
IM-1060 33 in (838 mm)
CM-1060 45 in (1,143 mm)
IM-1250 63 in (1,600 mm)
IM-1530 63 in (1,600 mm)
IM-1530 63 in (1,600 mm)
X
X
Contact Infiltrator Water Technologies at (800) 221-4436 or info@infiltratorwater.com for additional information. 7
TANK03 0723
Infiltrator Water Technologies, LLC (“Infiltrator”)
INFILTRATOR® SEPTIC TANK LIMITED WARRANTY FIVE (5) YEAR
MATERIALS AND WORKMANSHIP LIMITED WARRANTY
(a) This limited warranty is extended to the end user of an Infiltrator Tank. A Tank manufactured by Infiltrator, when installed and operated in accordance with Infiltrator’s
installation instructions and local regulation by a person or company that is properly qualified to install the Infiltrator tank in accordance with applicable state and/or local
requirements, is warranted to you: (i) against defective materials and workmanship for five (5) years after installation. Infiltrator will, at its option, (i) repair the defective
product or (ii) replace the defective materials. Infiltrator’s liability specifically excludes the cost of removal and/or installation of the Tank.
(b) In order to exercise its warranty rights, you must notify Infiltrator in writing at its corporate headquarters in Old Saybrook, Connecticut within fifteen (15) days of the alleged
defect.
(c) YOUR EXCLUSIVE REMEDY WITH RESPECT TO ANY AND ALL LOSSES OR DAMAGES RESULTING FROM ANY CAUSE WHATSOEVER SHALL BE SPECIFIED IN SUBPARAGRAPH (a)
ABOVE. INFILTRATOR SHALL IN NO EVENT BE LIABLE FOR ANY CONSEQUENTIAL OR INCIDENTAL DAMAGES OF ANY KIND, HOWEVER OCCASIONED, WHETHER BY NEGLIGENCE
OR OTHERWISE. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF INCIDENTAL OR CONSEQUENTIAL DAMAGES, SO THIS LIMITA TION OR EXCLUSION MAY
NOT APPLY TO YOU. THIS WARRANTY GIVES YOU SPECIFIC LEGAL RIGHTS AND YOU MAY ALSO HAVE OTHER RIGHTS WHICH VARY FROM STATE TO STATE.
(d) THIS LIMITED WARRANTY IS THE EXCLUSIVE WARRANTY GIVEN BY INFILTRATOR AND SUPERSEDES ANY PRIOR, CONTRARY, ADDITIONAL, OR SUBSEQUENT REPRESENTATIONS,
WHETHER ORAL OR WRITTEN. INFILTRATOR DISCLAIMS AND EXCLUDES TO THE GREATEST EXTENT ALLOWED BY LAW ALL OTHER WARRANTIES, WHETHER EXPRESS OR IMPLIED,
OR STATUTORY, INCLUDING ANY WARRANTY OF MERCHANTABILITY, FINESSE FOR A PARTICULAR PURPOSE AND ANY IMPLIED WARRANTIES OTHERWISE ARISING FROM
COURSE OF DEALING, COURSE OF PERFORMANCE, OR USAGE OF TRADE. NO PERSON (INCLUDING ANY EMPLOYEE, AGENT, DEALER, OR REPRESENTATIVE) IS AUTHORIZED TO
MAKE ANY REPRESENTATION OR WARRANTY CONCERNING THIS PRODUCT, EXCEPT TO REFER YOU TO THIS LIMITED WARRANTY. EXCEPT AS EXPRESSLY SET FORTH HEREIN,
THIS WARRANTY IS NOT A WARRANTY OF FUTURE PERFORMANCE, BUT ONLY A WARRANTY TO REPAIR OR REPLACE.
(e) YOU MAY ASSIGN THIS LIMITED WARRANTY TO A SUBSEQUENT PURCHASER OF YOUR HOME.
(f) NO REPRESENTATIVE OF INFILTRATOR HAS THE AUTHORITY TO CHANGE THIS LIMITED WARRANTY IN ANY MANNER WHATSOEVER, OR TO EXTEND THIS LIMITED WARRANTY.
(g) NO WARRANTY OF ANY KIND IS MADE WITH REGARD TO ANY PRODUCT, COMPONENTS, DEVICES, MEDIA OR TREATMENT UNITS WHICH ARE MANUFACTURED BY OTHERS AND
ARE INSTALLED IN AN INFILTRATOR TANK. USE OF THESE PRODUCTS ARE AT YOUR OWN RISK.
(h) THE INFILTRATOR TANK IS DESIGNED TO BE BURIED UNDERGROUND. NO WARRANTY OF ANY KIND IS MADE IF YOUR TANK IS NOT BURIED UNDERGROUND AS SPECIFIED IN
THE PRODUCT’S INSTALLATION INSTRUCTIONS.
CONDITIONS AND EXCLUSIONS
There are certain conditions or applications over which Infiltrator has no control. Defects or problems as a result of such conditions or applications are not the responsibility of
Infiltrator and are NOT covered under this warranty. They include failure to install the Tank in accordance with instructions or applicable regulatory requirements or guidance,
altering the Tank contrary to the installation instructions and disposing of chemicals or other materials contrary to normal tank usage.
The above represents the Standard Limited Warranty offered by Infiltrator. A limited number of regulatory jurisdictions have different warranty requirements. Any
purchaser of a Tank should contact Infiltrator’s corporate headquarters in Old Saybrook, Connecticut, prior to such purchase to obtain a copy of the applicable warranty, and
should carefully read that warranty prior to the purchase of a Tank.
Contact Infiltrator’s Technical Services Department for assistance at
1-800-221-4436 or info@infiltratorwater.com
10/7/2025
To Whom It May Concern:
We have been to the following site:
116 Crystal River Rd, Carbondale, Garfield County
We have verified that the system was started properly. The System went
through several cycles with no issues.
- Amperage and voltage of control panel, floats, and pump are all within
manufacturers specifications and tolerance at start up.
- Floats verified for functionality.
- The high-level alarm functions upon activation at control panel.
If you have any questions, please do not hesitate to call me at 719-395-6764,
ext. 13.
Sincerely,
Scott McIntosh
Service Manager
832‐R‐13‐002