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Preliminary Geotechnical Engineering
Report
__________________________________________________________________________
Pedcor Mulberry Apartments
Fort Collins, Colorado
September 14, 2021
Terracon Project No. 20205121
Prepared for:
Pedcor Investments, A Limited Liability Company
Carmel, Indiana
Prepared by:
Terracon Consultants, Inc.
Fort Collins, Colorado
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REPORT TOPICS
INTRODUCTION ............................................................................................................. 1
SITE CONDITIONS ......................................................................................................... 1
PROJECT DESCRIPTION .............................................................................................. 2
GEOTECHNICAL CHARACTERIZATION ...................................................................... 3
GEOTECHNICAL OVERVIEW ....................................................................................... 4
EARTHWORK................................................................................................................. 6
FOUNDATIONS ............................................................................................................ 11
PAVEMENTS ................................................................................................................ 12
FLOOR SYSTEMS........................................................................................................ 13
CORROSIVITY.............................................................................................................. 14
GENERAL COMMENTS ............................................................................................... 14
Note: This report was originally delivered in a web-based format.Orange Bold text in the report indicates a referenced
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ATTACHMENTS
EXPLORATION AND TESTING PROCEDURES
SITE LOCATION AND EXPLORATION PLANS
EXPLORATION RESULTS
SUPPORTING INFORMATION
Note: Refer to each individual Attachment for a listing of contents.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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REPORT SUMMARY
Topic 1 Overview Statement 2
Project
Overview
A preliminary geotechnical exploration has been performed for the proposed Pedcor
Mulberry Apartments project to be constructed northwest of Mulberry Street and
Greenfield Court in Fort Collins, Colorado. Ten (10) borings were performed to depths
of approximately 5 to 20½ feet below existing site grades. Supplementary geotechnical
engineering exploration should be performed at the site upon completion of initial
design studies in order to confirm or modify the recommendations contained in this
preliminary report and to allow the development of design-level recommendations more
specific to the proposed construction.
Subsurface
Conditions
Subsurface conditions encountered in our exploratory borings generally consisted of
about 3 to 4 feet of lean clay with varying amounts of sand over interlayered silty sand,
poorly graded sand and well graded sand with varying amounts of gravel encountered
to the maximum depth of exploration of about 20½ feet. Boring logs are presented in
the Exploration Results section of this report.
Groundwater
Conditions
Groundwater was encountered in most of our test borings at depths of about 6½ to 13
feet below existing site grades at the time of drilling. Groundwater levels can fluctuate
in response to site development and to varying seasonal and weather conditions,
irrigation on or adjacent to the site and fluctuations in nearby water features.
Geotechnical
Concerns
■Shallow groundwater was measured on this site. Terracon recommends
maintaining a separation of at least 3 feet between the bottom of proposed
below-grade foundations and measured groundwater levels. It is also possible
and likely that groundwater levels below this site may rise as water levels in
nearby water features rise. Final site grading should be planned and designed
to avoid cuts where shallow groundwater is known to exist, and also in areas
where such grading would create shallow groundwater conditions. If deeper
cuts and/or a basement level is planned for the proposed structures,
installation of a subsurface drainage system may be needed.
■Comparatively soft lean clay and very loose to loose sand soils were
encountered within the upper approximately 5 to 15 feet of the borings
completed at this site. These materials present a risk for potential settlement
of shallow foundations, floor slabs, pavements and other surficial
improvements. These materials can also be susceptible to disturbance and
loss of strength under repeated construction traffic loads and unstable
conditions could develop. Stabilization of soft and/or loose soils will be
required at some locations to provide adequate support for construction
equipment and proposed structures.
Earthwork
On-site soils typically appear suitable for use as general engineered fill and backfill on
the site provided they are placed and compacted as described in this report. Import
materials (if needed) should be evaluated and approved by Terracon prior to delivery
to the site. Earthwork recommendations are presented in the Earthwork section of
this report.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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Topic 1 Overview Statement 2
Ground
Improvements
Comparatively soft clay soils and very loose to loose soils were encountered in our
borings completed at this site. These materials will present a risk of shallow foundation
settlement. To reduce soil related movement and to enhance performance, we
anticipate recommending ground modification (over-excavation, moisture conditioning
and recompaction or rammed-aggregate piers) of the soils below foundations and floor
slabs. We anticipate over-excavation depths on the order of 4 to 6 feet below
foundations and floor slabs. Ground modification depths and recommendations will be
further discussed in a design-level report.
Grading and
Drainage
As discussed in the Grading and Drainage section of this report, surface drainage
should be designed, constructed and maintained to provide rapid removal of surface
water runoff away from the proposed buildings and pavements. Water should not be
allowed to pond adjacent to foundations or on pavements and conservative irrigation
practices should be followed to avoid wetting foundation/slab soils and pavement
subgrade. Excessive wetting of foundations/slab soils and subgrade can cause
movement and distress to foundations, floor slabs, concrete flatwork and pavements.
Foundations
Comparatively soft clay soils and very loose to loose soils were encountered at
anticipated shallow foundation bearing depths. Preliminary shallow foundation
settlement calculations indicate settlement may be an issue on this site. We believe
the proposed buildings can likely be constructed on shallow foundations such as
spread footing or post-tensioned slab foundation systems, provided some form of
ground modification takes place. This may include over-excavation of on-site soils
below the bottom of foundations and replacement with moisture conditioned,
properly compacted fill or aggregate piers. As a lower risk alternative, we believe the
proposed buildings can be constructed on deep foundations such as drilled piers or
helical piles bottomed in bedrock. Additional deeper boring will be necessary to
determine depth of bedrock.
Floor Systems
A concrete slab-on-grade Floor System will likely be appropriate for the proposed
buildings. In order to reduce risk for potential floor slab settlement, we anticipate over-
excavation will likely be necessary to depths of about 2 to 5 feet below floor slabs. If
little movement cannot be tolerated, a structurally-supported floor system, supported
independent of the subgrade materials, will be needed.
Pavements
We anticipate lean clay and silty sand soils will be present at proposed pavement
subgrade levels. These soils generally provide poor pavement support. Pavement
thickness will likely be on the order of 4 to 5 inches of asphalt over 6 to 8 inches of
aggregate base course in lightly-loaded areas and about 5 to 6 inches of asphalt over
about 6 to 10 inches of aggregate base course in heavy-duty areas.
Seismic
Considerations
As presented in the Seismic Considerations section of this report, the International
Building Code, which refers to Section 20 of ASCE 7, indicates the seismic site
classification for this site is D.
Construction
Observation
and Testing
Close monitoring of the construction operations and implementing drainage
recommendations discussed herein will be critical in achieving the intended
foundation, slab and pavement performance. We therefore recommend that Terracon
be retained to monitor this portion of the work.
General
Comments
This section contains important information about the limitations of this geotechnical
engineering report.
1.If the reader is reviewing this report as a pdf, the topics (bold orange font) above can be used to access the
appropriate section of the report by simply clicking on the topic itself.
2.This summary is for convenience only. It should be used in conjunction with the entire report for design
making and design purposes. It should be recognized that specific details were not included or fully
developed in this section, and the report must be read in its entirety for a comprehensive understanding of
the items contained herein.
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INTRODUC TION
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments
Northwest of Mulberry Street and Greenfield Court
Fort Collins, Colorado
Terracon Project No. 20205121
September 14, 2021
INTRODUCTION
This report presents the results of our subsurface exploration and geotechnical engineering
services performed for the proposed apartments to be located northwest of Mulberry Street and
Greenfield Court Fort Collins, Colorado. The purpose of these services is to provide information
and preliminary geotechnical engineering recommendations relative to:
■Subsurface soil conditions ■Foundation design and construction
■Groundwater conditions ■Floor system design and construction
■Site preparation and earthwork ■Pavement design and construction
■Excavation considerations
The geotechnical engineering scope of services for this project included the advancement of ten
(10) test borings to depths ranging from approximately 5 to 20½ feet below existing site grades.
Maps showing the site and boring locations are shown in the Site Location and Exploration
Plan sections, respectively. The results of the laboratory testing performed on soil samples
obtained from the site during the field exploration are included on the boring logs and as separate
graphs in the Exploration Results section of this report.
SITE CONDITIONS
The following description of site conditions is derived from our site visit in association with the
field exploration and our review of publicly available geologic and topographic maps.
Item Description
Parcel Information
The approximately 16.4-acre project site is located northwest of the
intersection of Mulberry Street and Greenfield Court in Fort Collins, Colorado.
The site is a northwest section of Parcel Number 8709000006. The
approximate Latitude/Longitude of the center of the site is 40.5869 °N /
105.0185 °W. See Site Location.
Existing
Improvements The site is currently irrigated farmland.
Current Ground
Cover The current ground cover is tilled soil currently used to cultivate beet crop.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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Item Description
Existing Topography The site is relatively flat.
PROJECT DESCRIPTION
Our final understanding of the project conditions is as follows:
Item Description
Information Provided The following project information was provided through a Request for
Proposals prepared by Pedcor Investments and dated December 8, 2020.
Project Description
Based on provided site plans, we understand the proposed project includes
14 apartment buildings, a clubhouse with a pool and a retention pond. Parking
and drive lanes and landscaped areas are also planned for the project.
Project
Understanding
Terracon’s proposed scope of services presented in this proposal has been
provided under the belief that this site will be used as apartments. As such,
Terracon would like to inform the Client that if this apartment project is
converted at any time to another purpose such as condominiums, the Client
understands the services Terracon is proposing are not applicable for a
condominium project and that a separate consultant will need to be retained
for such services. Terracon will have no liability for any such unintended use
of our services and Client agrees to defend, indeminify, and hold harmless
Terracon for any such unintended usage.
Proposed
Construction
We anticipate the proposed apartment buildings will be 2 to 3 stories and the
clubhouse will be 1 to 2 stories. We anticipate elevators will be included in
the proposed buildings. Based on our experience with similar projects, we
anticipate the buildings will likely be supported on post-tensioned slab
foundations.
Maximum Loads Loads were not provided at the time this report was prepared.
Grading/Slopes We anticipate minor cuts and fills on the order of 5 feet or less will be required
to achieve proposed grades.
Free-standing
Retaining Walls
Retaining walls are not expected to constructed as part of site development to
achieve final grades.
Pavements
We anticipate paved parking areas and drives, along with the installation of
utilities within. We assume both rigid (concrete) and flexible (asphalt)
pavement sections should be considered.
If project information or assumptions vary from what is described above or if location of
construction changes, we should be contacted as soon as possible to confirm and/or modify our
recommendations accordingly.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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GEOTECHNICAL CHARACTERIZATION
Subsurface Profile
We have developed a general characterization of the subsurface conditions based upon our
review of the subsurface exploration, laboratory data, geologic setting and our understanding of
the project. This characterization, termed GeoModel, forms the basis of our geotechnical
calculations and evaluation of site preparation and foundation options. Conditions encountered at
each exploration point are indicated on the individual logs. The individual logs and the GeoModel
can be found in the Exploration Results section this report.
As part of our analyses, we identified the following model layers within the subsurface profile. For
a more detailed view of the model layer depths at each boring location, refer to the GeoModel.
Model Layer Layer Name General Description Approximate Depth to
Bottom of Stratum
1 Lean to Fat
Clay
Lean to fat clay with varying amounts
of sand and trace amounts of gravel,
brown to dark brown with red and
white, moist, soft to stiff.
About 3 to 15½ feet below
existing site grades.
2 Silty Sand
Silty sand with varying amounts of
gravel, brown, moist to wet, very loose
to medium dense.
About 3 to 15 feet below
existing site grades.
3 Poorly Graded
Sand
Poorly graded sand with silt and
gravel, brown and light pinkish white,
dry to wet, loose to medium dense.
About 3 to 15 feet below
existing site grades.
4 Well Graded
Sand
Well graded sand with varying
amounts of gravel and trace amounts
of silt, brown and light pinkish white,
moist to wet, very loose to dense.
About 9 to 20½ feet below
existing site grades.
As noted in General Comments, this characterization is based upon widely spaced exploration
points across the site and variations are likely.
Groundwater Conditions
The boreholes were observed while drilling and shortly after completion for the presence and level
of groundwater. The water levels observed in the boreholes are noted on the attached boring logs,
and are summarized below:
Boring Number Depth to Groundwater after
Drilling, ft.
Elevation of Groundwater after
Drilling, ft.
B-1 13 4,928
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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Boring Number Depth to Groundwater after
Drilling, ft.
Elevation of Groundwater after
Drilling, ft.
B-2 11 4,928
B-3 9.6 4,924.4
B-4 11.6 4,928.4
B-5 7.6 4,928.4
B-6 Not encountered -
B-7 10½4,926½
P-1 Not encountered -
R-1 6½4,928½
R-2 8.3 4,926.7
These observations represent short-term groundwater conditions at the time of and shortly after
the field exploration and may not be indicative of other times or at other locations. Groundwater
levels can be expected to fluctuate with varying seasonal and weather conditions, and other
factors.
Groundwater level fluctuations occur due to seasonal variations in the water levels present in
nearby water features, amount of rainfall, runoff and other factors not evident at the time the
borings were performed. Therefore, groundwater levels during construction or at other times in
the life of the structure(s) may be higher or lower than the levels indicated on the boring logs. The
possibility of groundwater level fluctuations should be considered when developing the design
and construction plans for the project.
Fluctuations in groundwater levels can best be determined by implementation of a groundwater
monitoring plan. Such a plan would include installation of groundwater piezometers, and periodic
measurement of groundwater levels over a sufficient period of time.
GEOTECHNICAL OVERVIEW
The preliminary recommendations presented in this report are based on the assumption that the
subsurface conditions encountered in the widely spaced preliminary borings provide an accurate
representation of the entire site. Supplementary geotechnical engineering services should be
performed at the site upon completion of initial design studies in order to confirm or modify the
recommendations contained in this preliminary report and to allow the development of design-
level recommendations more specific to the proposed construction.
Based on subsurface conditions encountered in the borings, the site appears suitable for the
proposed construction from a geotechnical point of view provided certain precautions and design
and construction recommendations described in this report are followed. We have identified
several geotechnical conditions that could impact design, construction and performance of the
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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proposed structures, pavements, and other site improvements. These included existing, shallow
groundwater and potentially loose sand soils and comparatively soft, low strength clay soils.
These conditions will require particular attention in project planning, design and during
construction and are discussed in greater detail in the following sections.
Shallow Groundwater
As previously stated, groundwater was measured at depths ranging from about 6½ to 13 feet
below existing site grades. In general, measured groundwater levels were shallowest on the
southeast portion of the site in the vicinity of Boring Nos. B-7, R-1 and R-2. Terracon recommends
maintaining a separation of at least 3 feet between the bottom of proposed below-grade
foundations and measured groundwater levels. It is also possible and likely that groundwater
levels below this site may rise as water levels in the Cache la Poudre River and the Lake Canal
rise. Final site grading should be planned and designed to avoid cuts where shallow groundwater
is known to exist, and also in areas where such grading would create shallow groundwater
conditions. If deeper cuts are unavoidable, temporary construction dewatering and/or installation
of a subsurface drainage system may be needed.
Low Strength Soils
Comparatively soft lean clay soils and very loose to loose sand soils were encountered within the
upper approximately 5 to 15 feet of the borings completed at this site. These materials present a
risk for potential settlement of shallow foundations, floor slabs, pavements and other surficial
improvements. These materials can also be susceptible to disturbance and loss of strength under
repeated construction traffic loads and unstable conditions could develop. Stabilization of soft
and/or loose soils will be required at some locations to provide adequate support for construction
equipment and proposed structures.
Foundation and Floor System Recommendations
Comparatively soft lean clay and very loose to loose sand soils were encountered at anticipated
shallow foundation bearing depths. Preliminary shallow foundation settlement calculations
indicate settlement may be an issue on this site. We believe the proposed buildings can likely be
constructed on shallow foundations such as spread footing or post-tensioned slab foundation
systems, provided some form of ground modification takes place. This may include over-
excavation of on-site soils below the bottom of foundations and replacement with moisture
conditioned, properly compacted fill or aggregate piers. As a lower risk alternative, we believe the
proposed buildings can be constructed on deep foundations such as drilled piers or helical piles
bottomed in bedrock. Additional deeper boring will be necessary to determine depth of bedrock.
A concrete slab-on-grade Floor System will likely be appropriate for the proposed buildings. In order
to reduce risk for potential floor slab settlement, we anticipate over-excavation will likely be necessary
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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to depths of about 2 to 5 feet below floor slabs. If little movement cannot be tolerated, a structurally-
supported floor system, supported independent of the subgrade materials, will be needed.
Preliminary recommendations for foundations for the proposed structures and related structural
elements are presented in the following sections.
The General Comments section provides an understanding of the report limitations.
EARTHWORK
The following presents recommendations for site preparation, excavation, subgrade preparation,
fill materials, compaction requirements, utility trench backfill, grading and drainage and exterior
slab design and construction. Earthwork on the project should be observed and evaluated by
Terracon. Evaluation of earthwork should include observation and/or testing of over-excavation,
removal of existing fill, subgrade preparation, placement of engineered fills, subgrade stabilization
and other geotechnical conditions exposed during the construction of the project.
Site Preparation
Prior to placing any fill, strip and remove existing vegetation, topsoil, and any other deleterious
materials from the proposed construction areas. Stripped organic materials should be wasted from
the site or used to re-vegetate landscaped areas after completion of grading operations. Prior to
the placement of fills, the site should be graded to create a relatively level surface to receive fill, and
to provide for a relatively uniform thickness of fill beneath proposed structures.
Excavation
It is anticipated that excavations for the proposed construction can be accomplished with
conventional earthmoving equipment. Excavations into the on-site soils will encounter weak and/or
saturated soil conditions with possible caving conditions.
The soils to be excavated can vary significantly across the site as their classifications are based
solely on the materials encountered in widely-spaced exploratory test borings. The contractor
should verify that similar conditions exist throughout the proposed area of excavation. If different
subsurface conditions are encountered at the time of construction, the actual conditions should be
evaluated to determine any excavation modifications necessary to maintain safe conditions.
Although evidence of fills or underground facilities such as grease pits, septic tanks, vaults,
basements, and utilities was not observed during the site reconnaissance, such features could be
encountered during construction. If unexpected underground facilities are encountered, such
features should be removed and the excavation thoroughly cleaned prior to backfill placement
and/or construction.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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Depending upon depth of excavation and seasonal conditions, surface water infiltration and/or
groundwater may be encountered in excavations on the site. It is anticipated that pumping from
sumps may be utilized to control water within excavations. Well points may be required for
significant groundwater flow, or where excavations penetrate groundwater to a significant depth.
The subgrade soil conditions should be evaluated during the excavation process and the stability
of the soils determined at that time by the contractors’ Competent Person. Slope inclinations flatter
than the OSHA maximum values may have to be used. The individual contractor(s) should be
made responsible for designing and constructing stable, temporary excavations as required to
maintain stability of both the excavation sides and bottom. All excavations should be sloped or
shored in the interest of safety following local, and federal regulations, including current OSHA
excavation and trench safety standards.
As a safety measure, it is recommended that all vehicles and soil piles be kept a minimum lateral
distance from the crest of the slope equal to the slope height. The exposed slope face should be
protected against the elements.
Subgrade Preparation
After the deleterious material been removed from the construction area, the top 10 inches of the
exposed ground surface should be scarified, moisture conditioned, and recompacted to at least
95 percent of the maximum dry unit weight as determined by ASTM D698 before any new fill or
foundation or pavement is placed.
After the bottom of the excavation has been compacted, engineered fill can be placed to bring the
building pad and pavement subgrade to the desired grade. Engineered fill should be placed in
accordance with the recommendations presented in subsequent sections of this report.
The stability of the subgrade may be affected by precipitation, repetitive construction traffic or
other factors. If unstable conditions develop, workability may be improved by scarifying and
drying. Alternatively, over-excavation of wet zones and replacement with granular materials may
be used, or crushed gravel and/or rock can be tracked or “crowded” into the unstable surface soil
until a stable working surface is attained. Use of lime, fly ash, or geotextiles could also be
considered as a stabilization technique. Laboratory evaluation is recommended to determine the
effect of chemical stabilization on subgrade soils prior to construction. Lightweight excavation
equipment may also be used to reduce subgrade pumping.
Fill Materials
The on-site soils or approved granular and low plasticity cohesive imported materials may be used
as fill material. The earthwork contractor should expect significant mechanical processing and
moisture conditioning of the site soils and/or bedrock will be needed to achieve proper compaction
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
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Imported soils (if required) should meet the following material property requirements:
Gradation Percent finer by weight (ASTM C136)
4”100
3”70-100
No. 4 Sieve 30-100
No. 200 Sieve 60 (max.)
Soil Properties Values
Liquid Limit 35 (max.)
Plasticity Index 15 (max.)
Other import fill materials types may be suitable for use on the site depending upon proposed
application and location on the site, and could be tested and approved for use on a case-by-case
basis.
Compaction Requirements
Engineered fill should be placed and compacted in horizontal lifts, using equipment and procedures
that will produce recommended moisture contents and densities throughout the lift.
Item Description
Fill lift thickness
9 inches or less in loose thickness when heavy, self-
propelled compaction equipment is used
4 to 6 inches in loose thickness when hand-guided
equipment (i.e. jumping jack or plate compactor) is used
Minimum compaction requirements 95 percent of the maximum dry unit weight as determined by
ASTM D698
Moisture content cohesive soil (clay)-1 to +3 % of the optimum moisture content
Moisture content cohesionless soil
(sand)-3 to +3 % of the optimum moisture content
1.We recommend engineered fill be tested for moisture content and compaction during placement. Should the
results of the in-place density tests indicate the specified moisture or compaction limits have not been met,
the area represented by the test should be reworked and retested as required until the specified moisture
and compaction requirements are achieved.
2.Specifically, moisture levels should be maintained low enough to allow for satisfactory compaction to be
achieved without the fill material pumping when proof rolled.
3.Moisture conditioned clay materials should not be allowed to dry out. A loss of moisture within these materials
could result in an increase in the material’s expansive potential. Subsequent wetting of these materials could
result in undesirable movement.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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Utility Trench Backfill
All trench excavations should be made with sufficient working space to permit construction including
backfill placement and compaction.
All underground piping within or near the proposed structures should be designed with flexible
couplings, so minor deviations in alignment do not result in breakage or distress. Utility knockouts
in foundation walls should be oversized to accommodate differential movements. It is imperative
that utility trenches be properly backfilled with relatively clean materials. If utility trenches are
backfilled with relatively clean granular material, they should be capped with at least 18 inches of
cohesive fill in non-pavement areas to reduce the infiltration and conveyance of surface water
through the trench backfill.
Utility trenches are a common source of water infiltration and migration. All utility trenches that
penetrate beneath the buildings should be effectively sealed to restrict water intrusion and flow
through the trenches that could migrate below the buildings. We recommend constructing an
effective clay “trench plug” that extends at least 5 feet out from the face of the building exteriors.
The plug material should consist of clay compacted at a water content at or above the soil’s optimum
water content. The clay fill should be placed to completely surround the utility line and be compacted
in accordance with recommendations in this report.
It is strongly recommended that a representative of Terracon provide full-time observation and
compaction testing of trench backfill within building and pavement areas.
Grading and Drainage
Grades must be adjusted to provide effective drainage away from the proposed buildings during
construction and maintained throughout the life of the proposed project. Infiltration of water into
foundation excavations must be prevented during construction. Landscape irrigation adjacent to
foundations should be minimized or eliminated. Water permitted to pond near or adjacent to the
perimeter of the structures (either during or post-construction) can result in significantly higher
soil movements than those discussed in this report. As a result, any estimations of potential
movement described in this report cannot be relied upon if positive drainage is not obtained and
maintained, and water is allowed to infiltrate the fill and/or subgrade.
Exposed ground (if any) should be sloped at a minimum of 10 percent grade for at least 10 feet
beyond the perimeter of the proposed buildings, where possible. Locally, flatter grades may be
necessary to transition ADA access requirements for flatwork. The use of swales, chases and/or
area drains may be required to facilitate drainage in unpaved areas around the perimeter of the
buildings. Backfill against foundations and exterior walls should be properly compacted and free
of all construction debris to reduce the possibility of moisture infiltration. After construction of the
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
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proposed buildings and prior to project completion, we recommend verification of final grading be
performed to document positive drainage, as described above, has been achieved.
Flatwork and pavements will be subject to post-construction movement. Maximum grades
practical should be used for paving and flatwork to prevent areas where water can pond. In
addition, allowances in final grades should take into consideration post-construction movement
of flatwork, particularly if such movement would be critical. Where paving or flatwork abuts the
structures, care should be taken that joints are properly sealed and maintained to prevent the
infiltration of surface water.
Planters located adjacent to structures should preferably be self-contained. Sprinkler mains and
spray heads should be located a minimum of 5 feet away from the building line(s). Low-volume,
drip style landscaped irrigation should be used sparingly near the building. Roof drains should
discharge on to pavements or be extended away from the structures a minimum of 10 feet through
the use of splash blocks or downspout extensions. A preferred alternative is to have the roof
drains discharge by solid pipe to storm sewers, a detention pond, or other appropriate outfall.
Exterior Slab Design and Construction
Exterior slabs on-grade, exterior architectural features, and utilities founded on, or in backfill or
the site soils will likely experience some movement due to the volume change of the material.
Potential movement could be reduced by:
n Minimizing moisture increases in the backfill;
n Controlling moisture-density during placement of the backfill;
n Using designs which allow vertical movement between the exterior features and
adjoining structural elements; and
n Placing control joints on relatively close centers.
Construction Observation and Testing
The earthwork efforts should be monitored under the direction of Terracon. Monitoring should
include documentation of adequate removal of vegetation and topsoil, proof rolling, and mitigation
of areas delineated by the proof roll to require mitigation. Each lift of compacted fill should be
tested, evaluated, and reworked as necessary until approved by Terracon prior to placement of
additional lifts.
In areas of foundation excavations, the bearing subgrade and exposed conditions at the base of
the recommended over-excavation should be evaluated under the direction of Terracon. In the
event that unanticipated conditions are encountered, Terracon should prescribe mitigation
options.
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In addition to the documentation of the essential parameters necessary for construction, the
continuation of Terracon into the construction phase of the project provides the continuity to
maintain Terracon’s evaluation of subsurface conditions, including assessing variations and
associated design changes.
FOUNDATIONS
Foundation selection will be dependent upon the type of construction planned, foundation loading
conditions and geometry, site specific geotechnical conditions and final site grading
configurations. Additional geotechnical exploration will be necessary on the site in order to more
accurately define subsurface conditions and to develop specific foundation recommendations and
design parameters after final building location, site grading and type of construction have been
determined.
Field and laboratory testing completed for this study indicate the clay soils have negligible to low
swell potential at their in-place moisture content and density. Furthermore, the clays typically
exhibit negligible to low compressibility (settlement potential) when loaded. Considering the
subsurface conditions encountered in the preliminary test borings, it appears several foundation
systems may be appropriate for use on the site and will depend primarily upon building foundation
loads.
For lightly-loaded structures, shallow foundation systems such as spread footings, reinforced
concrete mats, and/or post-tensioned slabs bearing on undisturbed native soils or properly
compacted engineered fill could be used for support of the structure provided some movement
can be tolerated and/or accounted for in the design.
Low strength and/or compressible clay and/or sand soils are present on this site. We do not
believe the subsoils at and within the zone of influence of shallow foundations have adequate
compressibility properties to support moderate to heavy foundation loads with less than an inch
of settlement. Based on this information and the preliminary geotechnical data, we anticipate
recommending ground modification consisting of over-excavation and recompaction or aggregate
piers for this site. As a lower risk alternative, we believe the heavily-loaded structures can be
constructed on deep foundations such as drilled piers or helical piles bottomed in bedrock.
Additional deeper boring will be necessary to determine depth of bedrock.
Deep Foundations
Deep foundations, such as drilled piers socketed into bedrock, are commonly used for structures
with moderate to heavy loads and where compressible or lower strength soils are present in order
to control settlement and post-construction foundation movement. Competent bedrock was not
encountered in the borings completed on this site. We recommend subsequent design-level
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Responsive ■Resourceful ■Reliable 12
geotechnical investigations at this site include extending borings to identify depths to competent
bedrock.
Shallow Foundations
Data from this study indicates the native clay soils have negligible to low swell potential at their
in-place moisture content and density. Based on the preliminary data, we believe lightly-loaded
structures could be supported on shallow foundations provided some movement can be tolerated
and site grading fill is controlled so that it has low swell potential.
However, due to the presence of lower strength and comparatively soft clay and very loose to
loose sand soils, some method of ground modification/soil improvement below foundations will
be needed in order to reduce settlement potential. This could include over-excavation and
replacement with select imported granular materials. Soil improvement depth below footings could
be in the range of 4 to 6 feet, or more, depending upon building specific geotechnical conditions
and actual foundation loads and geometry. Ground improvement using aggregate piers may also
be used.
Lightly-loaded spread footings bearing on native sands or on an appropriate thickness of properly
compacted fill may be preliminarily evaluated using a maximum bearing pressure in the range of
1,500 to 2,000 pounds per square foot (psf).
Additional geotechnical exploration will be necessary on the site in order to more accurately define
subsurface conditions and engineering properties of the soils and to develop specific foundation
recommendations and design parameters once final building location, actual foundation loads
and site grading have been determined.
PAVEMENTS
Assuming only minor cuts are planned for site development, we anticipate lean clays, silty sands
or site grading fill comprised of similar material will support pavements on most of the site. Soil
classification according to the American Association of State Highway and Transportation Officials
(AASHTO) and our experience indicate the near surface soils on the site offer poor pavement
support.
Preliminary data suggests the near surface clays have low swell potential when wetted. Therefore,
it does not appear special design and construction precautions to mitigate pavement heave
concerns will be needed for this site. Consequently, standard pavement construction and
practices and subgrade preparation methods should be appropriate for this site. However, cut
areas of the site (if any) may encounter groundwater and low strength soils which may require
stabilization to provide adequate support for pavements. Generally speaking, we recommend
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Responsive ■Resourceful ■Reliable 13
pavement subgrade be situated at least 3 feet, and preferable more, above groundwater. If this
minimum separation cannot be achieved, consideration should be given to installing pavement
subdrains. In any event, we recommend grading be planned and designed to avoid cuts.
The preliminary pavement thicknesses presented are based on assumed 18-kip equivalent daily
load application (EDLA) values of 3 to 5 for car parking areas only and 10 to 15 for truck access
and drive lanes. For planning purposes and preliminary cost estimating, we anticipate a pavement
section of around 4 to 5 inches of asphalt over 6 to 8 inches of aggregate base course in lightly-
loaded areas and about 5 to 6 inches of asphalt over about 6 to 10 inches of aggregate base course
in heavy-duty areas.
A detailed subgrade evaluation and pavement thickness design should be completed during the
design-level geotechnical exploration. The final design will account for traffic type and volume and
variations in pavement subgrade soils which may occur in cut/fill sections required to bring the site
to construction grade and within the actual pavement areas.
FLOOR SYSTEMS
Swell-consolidation tests indicate the clay soils likely to influence floor slab performance on this
site have negligible to low swell potential at their in-place moisture content and density.
Engineered fill consisting of the on-site soils and/or import materials having similar or better
properties is expected to have low swell potential provided it is properly moisture conditioned and
compacted.
Even when bearing on properly prepared soils, movement of the slab-on-grade floor system is
possible should the subgrade soils undergo an increase in moisture content. A concrete slab-on-
grade Floor System will likely be appropriate for the proposed buildings. In order to reduce risk for
potential floor slab settlement, we anticipate over-excavation will likely be necessary to depths of
about 2 to 5 feet below floor slabs. If little movement cannot be tolerated, a structurally-supported
floor system, supported independent of the subgrade materials, will be needed. If conventional slab-
on-grade is utilized, the subgrade soils should be prepared as presented in the Earthwork section
of this report.
Other typical slab-on-grade design and construction considerations commonly used in the front
range are as follows:
n Positive separations and/or isolation joints should be provided between slabs and all
foundations, columns, or utility lines to allow independent movement.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Responsive ■Resourceful ■Reliable 14
n Control joints should be saw-cut in slabs in accordance with ACI Design Manual, Section
302.1R-37 8.3.12 (tooled control joints are not recommended) to control the location and
extent of cracking.
n Interior utility trench backfill placed beneath slabs should be compacted in accordance
with the recommendations presented in the Earthwork section of this report.
n Floor slabs should not be constructed on frozen subgrade.
n The use of a vapor retarder should be considered beneath concrete slabs that will be
covered with wood, tile, carpet or other moisture sensitive or impervious floor coverings,
or when the slab will support equipment sensitive to moisture. When conditions warrant
the use of a vapor retarder, the slab designer and slab contractor should refer to ACI
302 for procedures and cautions regarding the use and placement of a vapor retarder.
n Other design and construction considerations, as outlined in the ACI Design Manual,
Section 302.1R are recommended.
CORROSIVITY
Results of water-soluble sulfate testing indicate Exposure Class S0 and S1 according to ACI 318.
ASTM Type I or II portland cement should be specified for all project concrete on and below grade.
Foundation concrete should be designed for low to moderate sulfate exposure in accordance with
the provisions of the ACI Design Manual, Section 318, Chapter 4.
Sample Identification Water-soluble Sulfate
(%)
Boring No. B-1 at 2 feet <1
Boring No. B-5 at 2 feet <1
Boring No. B-7 at 2 feet <1
GENERAL COMMENTS
As the project progresses, we address assumptions by incorporating information provided by the
design team, if any. Revised project information that reflects actual conditions important to our
services is reflected in the final report. The design team should collaborate with Terracon to
confirm these assumptions and to prepare the final design plans and specifications. This
facilitates the incorporation of our opinions related to implementation of our geotechnical
recommendations. Any information conveyed prior to the final report is for informational purposes
only and should not be considered or used for decision-making purposes.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Responsive ■Resourceful ■Reliable 15
Our analysis and opinions are based upon our understanding of the project, the geotechnical
conditions in the area, and the data obtained from our site exploration. Natural variations will occur
between exploration point locations or due to the modifying effects of construction or weather.
The nature and extent of such variations may not become evident until during or after construction.
Terracon should be retained as the Geotechnical Engineer, where noted in the final report, to
provide observation and testing services during pertinent construction phases. If variations
appear, we can provide further evaluation and supplemental recommendations. If variations are
noted in the absence of our observation and testing services on-site, we should be immediately
notified so that we can provide evaluation and supplemental recommendations.
Our scope of services does not include either specifically or by implication any environmental or
biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of
pollutants, hazardous materials or conditions. If the owner is concerned about the potential for
such contamination or pollution, other studies should be undertaken.
Our services and any correspondence or collaboration through this system are intended for the
sole benefit and exclusive use of our client for specific application to the project discussed and
are accomplished in accordance with generally accepted geotechnical engineering practices with
no third-party beneficiaries intended. Any third-party access to services or correspondence is
solely for information purposes to support the services provided by Terracon to our client.
Reliance upon the services and any work product is limited to our client, and is not intended for
third parties. Any use or reliance of the provided information by third parties is done solely at their
own risk. No warranties, either express or implied, are intended or made.
Site characteristics as provided are for design purposes and not to estimate excavation cost. Any
use of our report in that regard is done at the sole risk of the excavating cost estimator as there
may be variations on the site that are not apparent in the data that could significantly impact
excavation cost. Any parties charged with estimating excavation costs should seek their own site
characterization for specific purposes to obtain the specific level of detail necessary for costing.
Site safety, and cost estimating including, excavation support, and dewatering
requirements/design are the responsibility of others. If changes in the nature, design, or location
of the project are planned, our conclusions and recommendations shall not be considered valid
unless we review the changes and either verify or modify our conclusions in writing.
Responsive ■Resourceful ■Reliable
ATTACHMENTS
Contents:
EXPLORATION AND TESTING PROCEDURES
SITE LOCATION AND EXPLORATION PLANS
EXPLORATION RESULTS
SUPPORTING INFORMATION
Note: Refer to each individual Attachment for a listing of contents.
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 1 of 2
EXPLORATION AND TESTING PROCEDURES
Field Exploration
Pedcor Investments prescribed the following boring locations and depths:
Number of Borings Boring Depth (feet)Location
7 15 or auger refusal Planned buildings
2 20 or auger refusal Planned pond location
1 5 or auger refusal Planned pavement areas
Boring Layout and Elevations: We used handheld GPS equipment to locate borings with an
estimated horizontal accuracy of +/-20 feet. A ground surface elevation at each boring location
was obtained by Terracon by interpolation from USGS topographic maps.
Subsurface Exploration Procedures: We advanced soil borings with a truck-mounted drill rig
using continuous-flight, solid-stem augers. Three samples were obtained in the upper 10 feet of
each boring and at intervals of 5 feet thereafter. Soil sampling was performed using thin-wall tube,
modified California barrel and standard split-barrel sampling procedures. For the standard split-
barrel sampling procedure, a standard 2-inch outer diameter split-barrel sampling spoon is driven
into the ground by a 140-pound automatic hammer falling a distance of 30 inches. The number of
blows required to advance the sampling spoon the last 12 inches of a normal 18-inch penetration
is recorded as the Standard Penetration Test (SPT) resistance value. The SPT resistance values,
also referred to as N-values, are indicated on the boring logs at the test depths. For the modified
California barrel sampling procedure, a 2½-inch outer diameter split-barrel sampling spoon is
used for sampling. Modified California barrel sampling procedures are similar to standard split-
barrel sampling procedures; however, blow counts are typically recorded for 6-inch intervals for a
total of 12 inches of penetration. The samples were placed in appropriate containers, taken to our
soil laboratory for testing, and classified by a geotechnical engineer.
In addition, we observed and recorded groundwater levels during drilling observations.
Our exploration team prepared field boring logs as part of standard drilling operations including
sampling depths, penetration distances, and other relevant sampling information. Field logs
included visual classifications of materials encountered during drilling, and our interpretation of
subsurface conditions between samples. Final boring logs, prepared from field logs, represent
the geotechnical engineer's interpretation, and include modifications based on observations and
laboratory test results.
Property Disturbance: We backfilled borings with auger cuttings after completion. Our services
did not include repair of the site beyond backfilling our boreholes. However, after discussion with
Preliminary Geotechnical Engineering Report
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Responsive ■Resourceful ■Reliable EXPLORATION AND TESTING PROCEDURES 2 of 2
the project team, we mobilized a field crew to the site the following day to repair damage done to
irrigation ditches by the drill rig.
Laboratory Testing
The project engineer reviewed field data and assigned various laboratory tests to better
understand the engineering properties of various soil strata. Laboratory testing was conducted in
general accordance with applicable or other locally recognized standards. Procedural standards
noted in this report are for reference to methodology in general. In some cases, variations to
methods are applied as a result of local practice or professional judgement. Testing was
performed under the direction of a geotechnical engineer and included the following:
■Visual classification ■Moisture content
■Dry density ■Atterberg limits
■Grain-size analysis ■One-dimensional swell
■Water-soluble sulfates ■Unconfined compressive strength
Our laboratory testing program includes examination of soil samples by an engineer. Based on
the material’s texture and plasticity, we described and classified soil samples in accordance with
the Unified Soil Classification System (USCS). Soil samples obtained during our field work will
be disposed of after laboratory testing is complete unless a specific request is made to temporarily
store the samples for a longer period of time.
Responsive ■Resourceful ■Reliable
SITE LOCATION AND EXPLORATION PLANS
Contents:
Site Location Plan
Exploration Plan
Note: All attachments are one page unless noted above.
SITE LOCATION
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Note to Preparer: This is a large table with outside borders. Just click inside the table
above this text box, then paste your GIS Toolbox image.
When paragraph markers are turned on you may notice a line of hidden text above and
outside the table – please leave that alone. Limit editing to inside the table.
The line at the bottom about the general location is a separate table line. You can edit
it as desired, but try to keep to a single line of text to avoid reformatting the page.
SITE LOCA TION
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS
EXPLORATION PLAN
Pedcor Mulberry Apartments ■ Fort Collins, Colorado
September 14, 2021 ■ Terracon Project No. 20205121
Note to Preparer: This is a large table with outside borders. Just click inside the table
above this text box, then paste your GIS Toolbox image.
When paragraph markers are turned on you may notice a line of hidden text above and
outside the table – please leave that alone. Limit editing to inside the table.
The line at the bottom about the general location is a separate table line. You can edit
it as desired, but try to keep to a single line of text to avoid reformatting the page.
EXPLORATION P LAN
DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS
EXPLORATION RESULTS
Contents:
GeoModel
Boring Logs (10 pages)
Atterberg Limits
Grain Size Distribution (2 pages)
Consolidation/Swell (3 pages)
Unconfined Compressive Strength
Corrosivity
Note: All attachments are one page unless noted above.
4,914
4,916
4,918
4,920
4,922
4,924
4,926
4,928
4,930
4,932
4,934
4,936
4,938
4,940
4,942
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Pedcor Mulberry Apartments Fort Collins, CO
Terracon Project No. 20205121
Layering shown on this figure has been developed by the
geotechnical engineer for purposes of modeling the subsurface
conditions as required for the subsequent geotechnical engineering
for this project.
Numbers adjacent to soil column indicate depth below ground
surface.
NOTES:
B-1
B-2
B-3
B-4
B-5
B-6
B-7
P-1
R-1 R-2
GEOMODEL
This is not a cross section. This is intended to display the Geotechnical Model only. See individual logs for more detailed conditions.
Groundwater levels are temporal. The levels shown are representative of the date
and time of our exploration. Significant changes are possible over time.
Water levels shown are as measured during and/or after drilling. In some cases,
boring advancement methods mask the presence/absence of groundwater. See
individual logs for details.
First Water Observation
Poorly graded sand with silt and gravel, brown and light
pinkish white, dry to wet, loose to medium dense.3
Well graded sand with varying amounts of gravel and trace
amounts of silt, brown and light pinkish white, moist to wet,
very loose to dense.
4
LEGEND
Sandy Lean Clay
Poorly-graded Sand with
Silt and Gravel
Silty Sand with Gravel
Well-graded Sand with
Gravel
Lean Clay with Sand
Silty Sand
Well-graded Sand with Silt
and Gravel
Fat Clay
Model Layer General DescriptionLayer Name
Lean clay with varying amounts of sand and trace amounts of
gravel, brown to dark brown with red and white, moist, soft to
stiff.
1
Silty sand with varying amounts of gravel, brown, moist to
wet, very loose to medium dense.2
POORLY GRADED
SAND
WELL GRADED SAND
LEAN CLAY
SILTY SAND
3
15
1
3
13
2.5
4
11
15.5
1
3
2
4
11
4
15
3
29.6
3
9
14
15
2
1
2
4
11.6
4
5.5
14
15.5
3
2
4
2
7.6
4
14
15.5
2
4
1
3.5
9
15
2
4
2
10.5
4
5
3
2
3
4
20.5
1
2
4
6.5
4
9
19
20
1
2
4
2
8.3
2-2-2
N=4
3-6
2-3-5
N=8
12-20
14.4
10.4
18.6
10.6
118
130
SANDY LEAN CLAY, dark brown, moist, soft
POORLY GRADED SAND WITH SILT AND
GRAVEL, brown with light pinkish white, moist,
loose to medium dense
interlayered sandy lean clay and clayey sand, light
brown to brown, moist to wet
Boring Terminated at 15 Feet
3.0
15.0
4938+/-
4926+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
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ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5885° Longitude: -105.0198°
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DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4941 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-1
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
13 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
1
3
SA
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3.7
10.2
20.3
13.5
132
101
4-6
2-2-6
N=8
6-11
4-5-10
N=15
<+0.1/150
SANDY LEAN CLAY, dark brown, moist, stiff
POORLY GRADED SAND WITH SILT AND
GRAVEL, brown and light pinkish white, moist,
loose
SILTY SAND WITH GRAVEL, fine to coarse
grained, brown, moist, medium dense
trace gravel, moist to wet
WELL GRADED SAND WITH GRAVEL, trace silt,
brown, wet, medium dense
Boring Terminated at 15.5 Feet
2.5
4.0
11.0
15.5
4936.5+/-
4935+/-
4928+/-
4923.5+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
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ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5872° Longitude: -105.0198°
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DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4939 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-2
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
11 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
1
3
2
4
SA
M
P
L
E
T
Y
P
E
2-2-2
N=4
2-4
4-4-7
N=11
8-18
19
5.2
5.5
21.0
6.6
97
138
NP
POORLY GRADED SAND WITH SILT AND
GRAVEL, light pinkish white and brown, dry to
moist, loose
SILTY SAND WITH GRAVEL (SM), brown, loose
to medium dense
interlayered sandy lean clay, brown, moist to wet,
trace iron oxide staining
trace gravel, light pinkish white and brown, wet
Boring Terminated at 15 Feet
4.0
15.0
4930+/-
4919+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5857° Longitude: -105.0198°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4934 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-3
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
9.6 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
3
2
SA
M
P
L
E
T
Y
P
E
1-1-1
N=2
2-4
2-3-8
N=11
18-30
+0.3/500 84
12.5
21.7
23.5
10.0
101
131
44-13-31
SILTY SAND WITH GRAVEL, brown, moist, very
loose
LEAN CLAY WITH SAND (CL), brown, moist, soft
to medium stiff
trace iron oxide staining
SILTY SAND, brown, moist to wet, medium dense
WELL GRADED SAND WITH SILT AND
GRAVEL, brown, wet, dense
Boring Terminated at 15 Feet
3.0
9.0
14.0
15.0
4937+/-
4931+/-
4926+/-
4925+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5876° Longitude: -105.0188°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4940 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-4
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
11.6 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
2
1
2
4
SA
M
P
L
E
T
Y
P
E
3-4
2-2-4
N=6
5-24
2-4-6
N=10
45
12.5
12.9
14.4
21.0
121
123
NP
POORLY GRADED SAND WITH SILT AND
GRAVEL, interlayered sandy lean clay, light brown
to dark brown, moist, loose, trace calcium carbonate
SILTY SAND (SM), brown, moist, loose
WELL GRADED SAND WITH GRAVEL, trace silt,
light pinkish white, medium dense
with silt
SILTY SAND, brown, wet, medium dense
Boring Terminated at 15.5 Feet
4.0
5.5
14.0
15.5
4932+/-
4930.5+/-
4922+/-
4920.5+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5864° Longitude: -105.0188°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4936 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-5
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
7.6 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
3
2
4
2
SA
M
P
L
E
T
Y
P
E
5-6
8-14-11
N=25
8-13
3-4-6
N=10 99
12.1
3.2
4.9
31.5
123
125
75-22-53
SILTY SAND, trace gravel, brown, moist, loose to
medium dense, trace calcium carbonate
WELL GRADED SAND WITH GRAVEL, trace
clay, light pinkish white and brown, medium dense
FAT CLAY (CH), brown with red and white, stiff
Boring Terminated at 15.5 Feet
4.0
14.0
15.5
4936+/-
4926+/-
4924.5+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5884° Longitude: -105.0181°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4940 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-6
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
No free water observed.
WATER LEVEL OBSERVATIONS
2
4
1
SA
M
P
L
E
T
Y
P
E
3-2-5
N=7
5-7
3-3-6
N=9
2-4
11.8
4.0
27.0
26.5
122
SILTY SAND, interlayered with sandy lean clay
and gravel, light brown to brown, moist, loose
WELL GRADED SAND WITH GRAVEL, trace silt,
light pinkish white, medium dense
SILTY SAND, interlayered sandy lean clay, black,
moist to wet, loose, trace iron oxide staining
wet
Boring Terminated at 15 Feet
3.5
9.0
15.0
4933.5+/-
4928+/-
4922+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5875° Longitude: -105.0181°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4937 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. B-7
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
10.5 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
2
4
2
SA
M
P
L
E
T
Y
P
E
3-5
4-5
124.4
18.8
114
112
NP
POORLY GRADED SAND WITH SILT AND
GRAVEL (SP-SM), interlayered sandy lean clay,
light brown to brown and orange, moist, loose
SILTY SAND WITH GRAVEL, interlayered sandy
lean clay, brown, loose, trace calcium carbonate
observed
Boring Terminated at 5 Feet
4.0
5.0
4930+/-
4929+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5881° Longitude: -105.0188°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4934 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. P-1
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
No free water observed.
WATER LEVEL OBSERVATIONS
3
2
SA
M
P
L
E
T
Y
P
E
2-2-2
N=4
2-2
6-5-13
N=18
4-5
4-11-20
N=31
4
20.3
6.1
10.6
8.9
17.6
129
NP
SANDY LEAN CLAY, dark brown, moist, soft
SILTY SAND, trace gravel, brown, moist, very
loose to loose
WELL GRADED SAND WITH GRAVEL (SW),
brown and light pinkish white, moist, very loose to
dense
trace silt
interlayered clayey sand, trace iron oxide staining
Boring Terminated at 20.5 Feet
3.0
4.0
20.5
4932+/-
4931+/-
4914.5+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
20
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5856° Longitude: -105.0188°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4935 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. R-1
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
6.5 feet at completion of drilling.
WATER LEVEL OBSERVATIONS
1
2
4
SA
M
P
L
E
T
Y
P
E
2-2
1-1-1
N=2
8-11
5-9-10
N=19
3-4
<-0.1/250
1710 5417.3
14.9
10.4
16.4
26.4
113
113
129
99
27-10-17
SANDY LEAN CLAY (CL), trace gravel, dark
brown, moist, soft
SILTY SAND, trace gravel, brown and red, moist,
very loose, trace iron oxide staining
WELL GRADED SAND WITH GRAVEL, trace silt,
light pinkish white and brown, moist to wet, medium
dense
SILTY SAND, brown, wet, loose
Boring Terminated at 20 Feet
4.0
9.0
19.0
20.0
4931+/-
4926+/-
4916+/-
4915+/-
Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.
TH
I
S
B
O
R
I
N
G
L
O
G
I
S
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
E
O
S
M
A
R
T
L
O
G
-
N
O
W
E
L
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
WA
T
E
R
L
E
V
E
L
OB
S
E
R
V
A
T
I
O
N
S
DE
P
T
H
(
F
t
.
)
5
10
15
20
FI
E
L
D
T
E
S
T
RE
S
U
L
T
S
SW
E
L
L
/
CO
N
S
O
L
I
D
A
T
I
O
N
(P
S
F
)
UN
C
O
N
F
I
N
E
D
CO
M
P
R
E
S
S
I
V
E
ST
R
E
N
G
T
H
(
p
s
f
)
PE
R
C
E
N
T
F
I
N
E
S
WA
T
E
R
CO
N
T
E
N
T
(
%
)
DR
Y
U
N
I
T
WE
I
G
H
T
(
p
c
f
)
ATTERBERG
LIMITS
LL-PL-PI
LOCATION See Exploration Plan
Latitude: 40.5859° Longitude: -105.0181°
GR
A
P
H
I
C
L
O
G
MO
D
E
L
L
A
Y
E
R
DEPTH ELEVATION (Ft.)
Approximate Surface Elev.: 4935 (Ft.) +/-
Page 1 of 1
Advancement Method:
Advanced using 4-inch diameter, continuous-flight, solid-stem
auger.
Abandonment Method:
Boring backfilled with auger cuttings upon completion.
Notes:
Project No.: 20205121
Drill Rig: CME 55
BORING LOG NO. R-2
Pedcor Investments, LLCCLIENT:
Carmel, IN
Driller: Drilling Engineers, Inc.
Boring Completed: 09-01-2021
PROJECT: Pedcor Mulberry Apartments
Elevations were interpolated from online
topographic maps.
See Supporting Information for explanation of
symbols and abbreviations.
Northwest of Mulberry Street and Greenfield Court
Fort Collins, CO
SITE:
Boring Started: 09-01-2021
1901 Sharp Point Dr Ste C
Fort Collins, CO
8.3 feet at completion of drilling
WATER LEVEL OBSERVATIONS
1
2
4
2
SA
M
P
L
E
T
Y
P
E
0
10
20
30
40
50
60
0 20 40 60 80 100
CH
o
r
OH
CL
or
OL
ML or OL
MH or OH
"U " Lin e
"A " L i n e
ATTERBERG LIMITS RESULTS
ASTM D4318
P
L
A
S
T
I
C
I
T
Y
I
N
D
E
X
LIQUID LIMIT
PROJECT NUMBER: 20205121
SITE: Northwest of Mulberry Street and
Greenfield Court
Fort Collins, CO
PROJECT: Pedcor Mulberry Apartments
CLIENT: Pedcor Investments, LLC
Carmel, IN
1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
B
O
R
A
T
O
R
Y
T
E
S
T
S
A
R
E
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
A
T
T
E
R
B
E
R
G
L
I
M
I
T
S
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
NP
44
NP
75
NP
NP
27
NP
13
NP
22
NP
NP
10
NP
31
NP
53
NP
NP
17
PIPLLLBoring ID Depth
B-3
B-4
B-5
B-6
P-1
R-1
R-2
18.5
84.1
44.9
99.4
11.8
3.6
54.2
Fines
4 - 5
4 - 5
4 - 5.5
14 - 15.5
2 - 3
9 - 10.5
2 - 3
SM
CL
SM
CH
SP-SM
SW
CL
SILTY SAND with GRAVEL
LEAN CLAY with SAND
SILTY SAND
FAT CLAY
POORLY GRADED SAND with SILT and GRAVEL
WELL-GRADED SAND with GRAVEL
SANDY LEAN CLAY
DescriptionUSCS
CL-ML
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0.0010.010.1110100
30 40 501.5 200681014413/4 1/2 60
GRAIN SIZE IN MILLIMETERS
PE
R
C
E
N
T
F
I
N
E
R
B
Y
W
E
I
G
H
T
HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
4 3/8 3 100 14032
GRAIN SIZE DISTRIBUTION
ASTM D422 / ASTM C136
6 16 20
PROJECT NUMBER: 20205121
SITE: Northwest of Mulberry Street and
Greenfield Court
Fort Collins, CO
PROJECT: Pedcor Mulberry Apartments
CLIENT: Pedcor Investments, LLC
Carmel, IN
1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
B
O
R
A
T
O
R
Y
T
E
S
T
S
A
R
E
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
R
A
I
N
S
I
Z
E
:
U
S
C
S
-
2
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
SILT OR CLAY
B-3
B-4
B-5
B-6
P-1
mediumcoarsecoarsefine fineCOBBLESGRAVELSAND
SILTY SAND with GRAVEL (SM)
LEAN CLAY with SAND (CL)
SILTY SAND (SM)
FAT CLAY (CH)
POORLY GRADED SAND with SILT and GRAVEL (SP-SM)
NP
44
NP
75
NP
1.47
4.85
1.96
838490196589899000000.00
NP
31
NP
53
NP
NP
13
NP
22
NP
25.09
8.73
29.99
17337082204429600000000.00
4 - 5
4 - 5
4 - 5.5
14 - 15.5
2 - 3
5.5
21.7
12.9
31.5
4.4
B-3
B-4
B-5
B-6
P-1
99.4
11.8
3.7
9.3
8.5
14.8
74.9
36.4
4 - 5
4 - 5
4 - 5.5
14 - 15.5
2 - 3
16.1
0.0
1.0
21.9
65.4
15.9
54.1
66.3
12.5
9.5
9.5
0.075
12.5
1.447
0.059
0.234
2.243
0.35
0.044
0.06
0.493
0.058
0.007
0.008
Boring ID Depth WC (%)LL PL PI Cc Cu
%Clay%Fines%Silt%Sand%Gravel Boring ID Depth D100 D60 D30 D10
USCS Classification
%Cobbles
0.0
0.0
0.0
0.0
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
0.0010.010.1110100
30 40 501.5 200681014413/4 1/2 60
GRAIN SIZE IN MILLIMETERS
PE
R
C
E
N
T
F
I
N
E
R
B
Y
W
E
I
G
H
T
HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS
4 3/8 3 100 14032
GRAIN SIZE DISTRIBUTION
ASTM D422 / ASTM C136
6 16 20
PROJECT NUMBER: 20205121
SITE: Northwest of Mulberry Street and
Greenfield Court
Fort Collins, CO
PROJECT: Pedcor Mulberry Apartments
CLIENT: Pedcor Investments, LLC
Carmel, IN
1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
B
O
R
A
T
O
R
Y
T
E
S
T
S
A
R
E
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
G
R
A
I
N
S
I
Z
E
:
U
S
C
S
-
2
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
SILT OR CLAY
R-1
R-2
mediumcoarsecoarsefine fineCOBBLESGRAVELSAND
WELL-GRADED SAND with GRAVEL (SW)
SANDY LEAN CLAY (CL)
NP
27
1.01NP
17
NP
10
8.999 - 10.5
2 - 3
10.6
17.3
R-1
R-2
3.6
54.2
9 - 10.5
2 - 3
22.5
0.3
73.9
45.5
19
9.5
2.592
0.094
0.868 0.288
Boring ID Depth WC (%)LL PL PI Cc Cu
%Clay%Fines%Silt%Sand%Gravel Boring ID Depth D100 D60 D30 D10
USCS Classification
%Cobbles
0.0
0.0
-4
-3
-2
-1
0
1
2
3
4
100 1,000 10,000
AX
I
A
L
S
T
R
A
I
N
,
%
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample swelled slightly upon wetting under an applied pressure of 150 psf.
PROJECT NUMBER: 20205121PROJECT: Pedcor MulberryApartments
SITE: Northwest of Mulberry Streetand Greenfield Court Fort Collins, CO
CLIENT: Pedcor Investments, LLC Carmel, IN1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
B
O
R
A
T
O
R
Y
T
E
S
T
S
A
R
E
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
6
5
1
5
5
0
4
5
-
S
W
E
L
L
/
C
O
N
S
O
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
132 4SANDY LEAN CLAY2 - 3 ftB-2
Specimen Identification Classification , pcf WC, %
-4
-3
-2
-1
0
1
2
3
4
100 1,000 10,000
AX
I
A
L
S
T
R
A
I
N
,
%
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibited 0.3 percent swell upon wetting under an applied pressure of 500 psf.
PROJECT NUMBER: 20205121PROJECT: Pedcor MulberryApartments
SITE: Northwest of Mulberry Streetand Greenfield Court Fort Collins, CO
CLIENT: Pedcor Investments, LLC Carmel, IN1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
B
O
R
A
T
O
R
Y
T
E
S
T
S
A
R
E
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
6
5
1
5
5
0
4
5
-
S
W
E
L
L
/
C
O
N
S
O
L
2
0
2
0
5
1
2
1
P
E
D
C
O
R
A
P
A
R
T
M
E
N
T
S
.
G
P
J
T
E
R
R
A
C
O
N
_
D
A
T
A
T
E
M
P
L
A
T
E
.
G
D
T
9
/
1
4
/
2
1
101 22LEAN CLAY with SAND(CL)4 - 5 ftB-4
Specimen Identification Classification , pcf WC, %
-4
-3
-2
-1
0
1
2
3
4
100 1,000 10,000
AX
I
A
L
S
T
R
A
I
N
,
%
PRESSURE, psf
SWELL CONSOLIDATION TEST
ASTM D4546
NOTES: Sample exhibited slight compression upon wetting under an applied pressure of 250 psf.
PROJECT NUMBER: 20205121PROJECT: Pedcor MulberryApartments
SITE: Northwest of Mulberry Streetand Greenfield Court Fort Collins, CO
CLIENT: Pedcor Investments, LLC Carmel, IN1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
B
O
R
A
T
O
R
Y
T
E
S
T
S
A
R
E
N
O
T
V
A
L
I
D
I
F
S
E
P
A
R
A
T
E
D
F
R
O
M
O
R
I
G
I
N
A
L
R
E
P
O
R
T
.
6
5
1
5
5
0
4
5
-
S
W
E
L
L
/
C
O
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113 17SILTY SAND4 - 5.5 ftR-2
Specimen Identification Classification , pcf WC, %
0
200
400
600
800
1,000
1,200
1,400
1,600
1,800
0 4 8 12 16
AXIAL STRAIN - %
UNCONFINED COMPRESSION TEST
ASTM D2166
CO
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PROJECT NUMBER: 20205121
SITE: Northwest of Mulberry Street and
Greenfield Court
Fort Collins, CO
PROJECT: Pedcor Mulberry Apartments
CLIENT: Pedcor Investments, LLC
Carmel, IN
1901 Sharp Point Dr Ste C
Fort Collins, CO
LA
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SAMPLE LOCATION:R-2 @ 2 - 3 feetSAMPLE TYPE: CARS
0.43
103.77
111
Strain Rate:in/min
Failure Strain:%
Calculated Saturation:%
Height:in.
Diameter:in.
SPECIMEN FAILURE PHOTOGRAPH
Remarks:
Percent < #200 SievePIPLLL
856
DESCRIPTION: SANDY LEAN CLAY(CL)
-0.0800
Dry Density:pcf
Moisture Content:%
14.02
2.06
2.6
Height / Diameter Ratio:
Calculated Void Ratio:
Undrained Shear Strength:(psf)
Unconfined Compressive Strength (psf)
171027
Assumed Specific Gravity:
1711
3.95
1.91
SPECIMEN TEST DATA
20.4
54.2
Project Number:
Service Date:
Report Date:
Client
Analyzed By:
322
2,688
B-7 557
2-3.5
2-3.5
B-1
B-5
2-3.5
The tests were performed in general accordance with applicable ASTM, AASHTO, or DOT test methods. This report is exclusively for the use of the client
indicated above and shall not be reproduced except in full without the written consent of our company. Test results transmitted herein are only applicable to the
actual samples tested at the location(s) referenced and are not necessarily indicative of the properties of other apparently similar or identical materials.
20205121
Field Engineer
09/10/21
09/10/21
10400 State Highway 191
Midland, Texas 79707
432-684-9600
Project
Water Soluble Sulfate (SO4), ASTM C 1580
(mg/kg)Sample Location
CHEMICAL LABORATORY TEST REPORT
Nohelia Monasterios
Pedcor Investments, LLC Pedcor Apartments Mulberry St
770 3rd Ave SW
Carmel, IN 46032-2036 Fort Collins, CO 80524
Northwest of Mulberry Street and Greenfield Court
Sample Depth
SUPPORTING INFORMATION
Contents:
General Notes
Unified Soil Classification System
Note: All attachments are one page unless noted above.
Pedcor Apartments Mulberry St Fort Collins, CO
Terracon Project No. 20205121
less than 500
1,000 to 2,000
> 8,000
Unconfined
Compressive Strength
Qu, (psf)
500 to 1,000
2,000 to 4,000
4,000 to 8,000
Modified
California
Ring
Sampler
Standard
Penetration
Test
N
(HP)
(T)
(DCP)
UC
(PID)
(OVA)
Standard Penetration Test
Resistance (Blows/Ft.)
Hand Penetrometer
Torvane
Dynamic Cone Penetrometer
Unconfined Compressive
Strength
Photo-Ionization Detector
Organic Vapor Analyzer
SAMPLING WATER LEVEL FIELD TESTS
GENERAL NOTES
DESCRIPTION OF SYMBOLS AND ABBREVIATIONS
Water levels indicated on the soil boring logs are
the levels measured in the borehole at the times
indicated. Groundwater level variations will occur
over time. In low permeability soils, accurate
determination of groundwater levels is not possible
with short term water level observations.
Water Initially
Encountered
Water Level After a
Specified Period of Time
Water Level After
a Specified Period of Time
Cave In
Encountered
Exploration point locations as shown on the Exploration Plan and as noted on the soil boring logs in the form of Latitude and
Longitude are approximate. See Exploration and Testing Procedures in the report for the methods used to locate the
exploration points for this project. Surface elevation data annotated with +/- indicates that no actual topographical survey was
conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic
maps of the area.
LOCATION AND ELEVATION NOTES
Soil classification as noted on the soil boring logs is based Unified Soil Classification System. Where sufficient laboratory data
exist to classify the soils consistent with ASTM D2487 "Classification of Soils for Engineering Purposes" this procedure is used.
ASTM D2488 "Description and Identification of Soils (Visual-Manual Procedure)" is also used to classify the soils, particularly
where insufficient laboratory data exist to classify the soils in accordance with ASTM D2487. In addition to USCS classification,
coarse grained soils are classified on the basis of their in-place relative density, and fine-grained soils are classified on the basis
of their consistency. See "Strength Terms" table below for details. The ASTM standards noted above are for reference to
methodology in general. In some cases, variations to methods are applied as a result of local practice or professional judgment.
DESCRIPTIVE SOIL CLASSIFICATION
The soil boring logs contained within this document are intended for application to the project as described in this document.
Use of these soil boring logs for any other purpose may not be appropriate.
RELEVANCE OF SOIL BORING LOG
Descriptive Term
(Consistency)
CONSISTENCY OF FINE-GRAINED SOILS
Hard
Very Loose
Loose
Medium Dense
Dense
Very Dense
Descriptive Term
(Density)
Standard Penetration
or N-Value
Blows/Ft.
0 - 3
4 - 9
10 - 29
30 - 50
> 50 Very Stiff
Standard Penetration or
N-Value
Blows/Ft.
Ring Sampler
Blows/Ft.
Ring Sampler
Blows/Ft.
5 - 9
Stiff
6 - 14
15 - 46
47 - 79
> 80
Medium Stiff
Soft
Very Soft
(50% or more passing the No. 200 sieve.)
Consistency determined by laboratory shear strength testing, field visual-manual
procedures or standard penetration resistance
STRENGTH TERMS
RELATIVE DENSITY OF COARSE-GRAINED SOILS
(More than 50% retained on No. 200 sieve.)
Density determined by Standard Penetration Resistance
2 - 4
4 - 8
8 - 15
15 - 30
> 30
0 - 1
3 - 4
< 3
10 - 18
19 - 42
> 42
0 - 5
_
UNIFIED SOIL CLASSIFICATION SYSTEM
UNIFIED SOI L CLASSI FICATI ON SYSTEM
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A
Soil Classification
Group
Symbol Group Name B
Coarse-Grained Soils:
More than 50% retained
on No. 200 sieve
Gravels:
More than 50% of
coarse fraction
retained on No. 4 sieve
Clean Gravels:
Less than 5% fines C
Cu ³ 4 and 1 £ Cc £ 3 E GW Well-graded gravel F
Cu < 4 and/or [Cc<1 or Cc>3.0]E GP Poorly graded gravel F
Gravels with Fines:
More than 12% fines C
Fines classify as ML or MH GM Silty gravel F, G, H
Fines classify as CL or CH GC Clayey gravel F, G, H
Sands:
50% or more of coarse
fraction passes No. 4
sieve
Clean Sands:
Less than 5% fines D
Cu ³ 6 and 1 £ Cc £ 3 E SW Well-graded sand I
Cu < 6 and/or [Cc<1 or Cc>3.0]E SP Poorly graded sand I
Sands with Fines:
More than 12% fines D
Fines classify as ML or MH SM Silty sand G, H, I
Fines classify as CL or CH SC Clayey sand G, H, I
Fine-Grained Soils:
50% or more passes the
No. 200 sieve
Silts and Clays:
Liquid limit less than 50
Inorganic:PI > 7 and plots on or above “A”
line J
CL Lean clay K, L, M
PI < 4 or plots below “A” line J ML Silt K, L, M
Organic:Liquid limit - oven dried < 0.75 OL Organic clay K, L, M, N
Liquid limit - not dried Organic silt K, L, M, O
Silts and Clays:
Liquid limit 50 or more
Inorganic:PI plots on or above “A” line CH Fat clay K, L, M
PI plots below “A” line MH Elastic Silt K, L, M
Organic:Liquid limit - oven dried < 0.75 OH Organic clay K, L, M, P
Liquid limit - not dried Organic silt K, L, M, Q
Highly organic soils:Primarily organic matter, dark in color, and organic odor PT Peat
A Based on the material passing the 3-inch (75-mm) sieve.
B If field sample contained cobbles or boulders, or both, add “with cobbles
or boulders, or both” to group name.
C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded
gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly
graded gravel with silt, GP-GC poorly graded gravel with clay.
D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded
sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded
sand with silt, SP-SC poorly graded sand with clay.
E Cu = D60/D10 Cc =
6010
2
30
DxD
)(D
F If soil contains ³ 15% sand, add “with sand” to group name.
G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.
H If fines are organic, add “with organic fines” to group name.
I If soil contains ³ 15% gravel, add “with gravel” to group name.
J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.
K If soil contains 15 to 29% plus No. 200, add “with sand” or “with
gravel,” whichever is predominant.
L If soil contains ³ 30% plus No. 200 predominantly sand, add
“sandy” to group name.
MIf soil contains ³ 30% plus No. 200, predominantly gravel, add
“gravelly” to group name.
N PI ³ 4 and plots on or above “A” line.
O PI < 4 or plots below “A” line.
P PI plots on or above “A” line.
Q PI plots below “A” line.