HomeMy WebLinkAboutTHE OVERLOOK - FDP - FDP160035 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTSUBSURFACE EXPLORATION REPORT
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
EEC PROJECT NO. 1152119
Prepared for:
Mr. Butch Stockover (stockover@aol.com)
c/o VFLA
419 Canyon Avenue, Suite 200
Fort Collins, Colorado 80521
Prepared by:
Earth Engineering Consultants, LLC
4396 Greenfield Drive
Windsor, Colorado 80550
4396 GREENFIELD DRIVE
WINDSOR, COLORADO 80550
(970) 545-3908 FAX (970) 663-0282
December 14, 2015
Mr. Butch Stockover (stockover@aol.com)
c/o VFLA
419 Canyon Avenue, Suite 200
Fort Collins, Colorado 80521
Re: Subsurface Exploration Report
JFK Luxury Apartments
Fort Collins, Colorado
EEC Project No. 1152119
Mr. Stockover:
Enclosed, herewith, are the results of the geotechnical subsurface exploration completed by
Earth Engineering Consultants, LLC (EEC) personnel for the proposed buildings and
associated pavement development for the JFK Luxury Apartments in Fort Collins, Colorado.
This exploration was completed in general accordance with our proposal dated November 12,
2015.
In summary, the subsurface materials encountered in the exploration borings completed on the
site generally consisted of approximately 2 to 7 feet of moderately plastic/moderately
expansive cohesive subgrade soil overlying sandstone/siltstone bedrock. The bedrock
extended to the maximum depth explored, approximately 35 feet. Groundwater was observed
in two of the soil borings at approximate depths of 11 and 14 feet below site grade. Perched
groundwater is likely with the shallow bedrock and the Larimer #2 Canal at the upper area of
the site.
Based on results of the field borings and laboratory testing, it is our opinion the proposed
lightly to moderately loaded building(s) could be supported on a conventional spread footing
foundation system bearing on the sandstone bedrock. No foundation should be founded
within existing site cohesive soils. Alternative foundation systems could be considered.
In the building floor and patio areas, we recommend the cohesive subgrade soils be removed
and replaced with low volume change fill. Within the pavement areas, we suggest a portion
of the in-situ cohesive soils could remain in-place although leaving the cohesive soils in-place
will involve a risk of future heaving within those areas.
SUBSURFACE EXPLORATION REPORT
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
EEC PROJECT NO. 1152119
December 14, 2015
INTRODUCTION
The subsurface exploration for the proposed JFK Luxury Apartments in Fort Collins, Colorado has
been completed. As a part of that exploration, seven (7) soil borings extending to depths of
approximately 25 to 35 feet below present site grades were advanced within proposed building areas
on the development parcel to obtain information on existing subsurface conditions. Two (2) other
borings were advanced to depths of approximately 10 feet in proposed site detention areas.
Individual boring logs and a diagram indicating the approximate boring locations are included with
this report.
We understand this project involves the construction of a new office building on the north portion of
this parcel and a mixed use commercial/residential building covering a large part of the central and
south part of the site. The proposed office building would be two-story, slab-on-grade. The
proposed commercial/residential building will be three to four stories over a parking garage being
below grade to the west and drive out to the east. We anticipate maximum wall and column loads
for the buildings would be on the order of 4 klf and 250 kips, respectively, along with light floor
loading conditions. On-site pavement improvements are currently planned as a part of the
development. Based on preliminary site cross sections, we expect cuts on the order of 10 feet may
be needed to develop the “underground” parking with smaller grade changes for the remainder of the
site.
The purpose of this report is to describe the subsurface conditions encountered in the soil borings
completed on the site, analyze and evaluate the test data and provide geotechnical recommendations
concerning design and construction of the foundations and support of floor slabs and pavements.
EXPLORATION AND TESTING PROCEDURES
The boring locations were established in the field by a representative of Earth Engineering
Consultants, LLC (EEC) by pacing and estimating angles from identifiable site features. Those
approximate boring locations are indicated on the attached boring location diagram. The locations
of the borings should be considerate accurate only to the degree implied by the methods used to
make the field measurements.
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December 14, 2015
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The borings were performed using a truck-mounted, CME-55 drill rig equipped with a hydraulic
head employed in drilling and sampling operations. The boreholes were advanced using 4-inch
nominal diameter continuous flight augers and samples of the subsurface materials encountered were
obtained using split-barrel and California barrel sampling procedures in general accordance with
ASTM Specifications D1586 and D3550, respectively.
In the split barrel and California barrel sampling procedures, standard sampling spoons are driven
into the ground by means of a 140-pound hammer falling a distance of 30 inches. The number of
blows required to advance the samplers is recorded and is used to estimate the in-situ relative density
of cohesionless soils and, to a lesser degree of accuracy, the consistency of cohesive soils and
hardness of weathered bedrock. All samples obtained in the field were sealed and returned to our
laboratory for further examination, classification and testing.
Moisture content tests were completed on each of the recovered samples. The unconfined strength
of appropriate samples was estimated using a calibrated hand penetrometer. The quantity and
plasticity of the fines in the subgrade were determined by washed sieve analysis and Atterberg limits
tests on selected samples. Swell/consolidation tests were completed on selected samples to evaluate
the potential for the subgrade soils and/or bedrock to change volume with changes in moisture and
load. Results of the outlined tests are indicated on the attached boring logs and summary sheets.
As part of the testing program, all samples were examined in the laboratory and classified in general
accordance with the attached General Notes and the Unified Soil Classification System, based on the
soil’s texture and plasticity. The estimated group symbol for the Unified Soil Classification System
is indicated on the boring logs and a brief description of that classification system is included with
this report. Classification of the bedrock was based on visual and tactual observation of disturbed
samples and auger cuttings. Coring and/or petrographic analysis may reveal other rock types.
SITE AND SUBSURFACE CONDITIONS
The proposed development lot is located east of John F. Kennedy Parkway south of Horsetooth Road
in Fort Collins. This property includes approximately 3 acres of previously undeveloped property
surrounded by commercial and multi-family development. The Larimer #2 Canal borders a portion
of the property boundary on the southwest. Grade change is estimated to be on the order of 10 to 15
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feet dropping to the north and east. The surfacing at the site is generally grass/weed covering.
Photographs of the site were taken during the subsurface exploration and are included with this
report.
An EEC field engineer was on site during the drilling operations to evaluate the subsurface
conditions encountered and direct the drilling activities. Field logs prepared by EEC site personnel
were based on visual and tactual observation of auger cuttings and disturbed samples. The boring
logs included with this report may contain modifications to the field logs based on results of
laboratory testing and engineering evaluation. Based on results of the field boring and laboratory
testing, subsurface conditions can be generalized as follows.
A thin mantle of vegetation/topsoil was encountered at the surface at the boring locations. The
topsoil/vegetation was generally underlain by lean clay with varying amounts of silt and sand.
Those soils were moderately plastic and moderately expansive at current moisture and density
conditions. The cohesive soils were underlain by sandstone/siltstone bedrock at depths ranging from
approximately 2 to 7 feet below ground surface. The bedrock was moderately hard to hard with low
swell potential measured in laboratory testing. Occasional cemented zones were observed in the
sandstone bedrock. The borings were terminated at depths of 10 to 35 feet in the sandstone/siltstone
bedrock.
The stratification boundaries indicated on the boring logs represent the approximate locations of
changes in soil and rock types. In-situ, the transition of materials may be gradual and indistinct.
WATER LEVEL OBSERVATIONS
Observations were made while drilling and after completion of boring to detect the presence and
depth to apparent groundwater. Groundwater was generally not observed in the boreholes at the
time of drilling. When checked approximately 24 hours after drilling, groundwater was observed in
borings B-1 and B-4 at depths of approximately 11.5 and 14.5 feet, respectively. The boreholes
were backfilled after the 24-hour observations; therefore, subsequent groundwater measurements
were not obtained.
Fluctuations in groundwater levels can occur over time depending on variations in hydrologic
conditions and other conditions not apparent at the time of this report. In addition, zones of perched
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and/or trapped water may be encountered at times throughout the year in more permeable areas
within the subgrade materials. Perched groundwater is commonly observed in soils above lower
permeability bedrock. With the Larimer #2 Canal located upslope on the high side of the site,
perched groundwater conditions should be expected during times when the canal is flowing. The
location and amount of perched water can vary over time depending on variations in hydrologic
conditions and other conditions not apparent at the time of this report.
ANALYSIS AND RECOMMENDATIONS
General Considerations
Precautions will be required in the design and construction of the new building(s) and new pavements
to address the near surface moderately expansive soils, excavation of the underlying well cemented
sandstone bedrock lenses, and potential perched water conditions.
The cohesive overburden soils on the site are relatively dry and show moderate swell potential in
laboratory testing. Floor slabs, pavements, flatwork and any other improvements supported directly on
the in-situ subgrade soils would likely experience post-construction heaving as the subgrade soils
expand with increases in moisture content. We recommend the cohesive soils be removed to the top of
bedrock and replaced with low to non-volume change materials in all floor slab, patio and any other
area where that post-construction heaving would be unacceptable.
It is anticipated that excavations for the proposed construction can be accomplished with
conventional heavy duty earthmoving equipment. However, excavations penetrating well-cemented
sandstone bedrock zones may require the use of specialized heavy-duty equipment such as a rock
hammer or core barrel to achieve final design elevations. Consideration should be given to
obtaining a unit price for difficult excavation in the contract documents for the project.
Depending upon the depth and proximity to the property line of lower level construction, a shoring
plan may be necessary to protect the adjacent sidewall slopes. The project design team should use the
subsurface information provided herein to properly design a mechanism for shoring protection. EEC is
available to provide supplemental design criteria or details such as but not limited to secant piles or
piers, soldier piers, or a tie-back/bracing concept.
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Site Preparation
Final site grades were not available at the time of this report; as such, the recommendations in this
report assume that cuts and fills on the order of 10 feet will be necessary to achieve design grades in
the “below grade” parking areas and general site cuts and fills may be on the order of 5 feet.
All of the existing in-situ cohesive soils should be removed in the new building areas and either
stockpiled for reuse as fill material or hauled off-site. In pavement areas, we recommend at least 2
feet of the in-place soils be removed and replaced/reworked understanding that heaving of the
pavements will occur to reflect the thickness of the cohesive soils left in-place. In-place cohesive
materials could remain in landscape areas with the acknowledgement that some future differential
movements could occur in the overlying improvements. It is our opinion the site cohesive soils
could be stockpiled for reuse as fill material although use of processed sandstone bedrock as fill
material would result in lower post-construction swell potential.
After stripping, over-excavating as necessary and completing all cuts, and prior to placement of any
fill material or site improvements, we recommend the exposed subsoils be scarified to a minimum
depth of 9 inches, adjusted in moisture content to within ±2% of standard Proctor optimum moisture
content, and compacted to at least 95% of the material's standard Proctor maximum dry density as
determined in accordance with ASTM Specification D698.
Fill soils required to develop the building, pavement and site subgrades, after the initial subgrade
zone (i.e. the layer beneath any over-excavation requirements) has been stabilized, should consist of
approved, low volume change material, which are free from organic matter and/or debris. We
recommend structural fill materials be placed and compacted within the building footprint including
adjacent patio areas and consist of essentially granular soils or processed sandstone excavated on-
site. The site sandstone used for fill should exclude larger sized cemented materials. We recommend
fill materials be placed in loose lifts not to exceed 9 inches thick and adjusted in moisture content to
within ±2% of optimum moisture content and compacted to at least 95% of the material’s maximum
dry density as determined in accordance with ASTM Specification D698, the standard Proctor
procedure.
Care should be exercised after preparation of the subgrades to avoid disturbing the subgrade
materials. Positive drainage should be developed away from the structures and pavement/flatwork
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areas to avoid wetting of subgrade materials. Subgrade materials becoming wet subsequent to
construction of the site improvements can result in unacceptable performance.
Foundations – Conventional Type Spread Footings
Based on the results of the field borings and laboratory testing, it is our opinion the proposed
buildings could be supported on conventional type spread footing foundations bearing on the
sandstone bedrock. In no case should any foundation system be placed on the existing on-site
cohesive overburden soils. Footings bearing on approved moderately hard sandstone could be
designed for a maximum net allowable bearing pressure of 5,000 psf. The net bearing pressure
refers to the pressure at foundation bearing level in excess of the minimum surrounding overburden
pressure. A minimum dead load pressure would not be required in the low swell potential bedrock.
Exterior footings and foundations in unheated areas should be protected from frost action. The
normal depth of frost protection in this location is a minimum depth of 30 inches. Continuous wall
footings should have a width of at least 12 inches. Isolated column pads should be at least 24 inches
by 24 inches. Footings should be proportioned to reduce differential foundation movement.
Proportioning on the basis of equal total settlement is recommended; however, proportioning to
relative constant dead-load pressure will also reduce differential settlement between adjacent
footings.
Total settlement resulting from the assumed structural loads is estimated to be on the order of 1 inch
or less. Differential settlement should be on the order of 1/2 of the estimated total settlement.
Care should be taken during construction to see that the footing foundations are supported on
suitable weathered sandstone. If unacceptable materials are encountered at foundation bearing level
at the time of construction, it may be necessary to extend the footing foundations to bear below the
unacceptable materials. Those conditions can best be evaluated in open excavations at the time of
construction.
Care should be taken during construction to avoid disturbing the foundation bearing materials.
Materials which are loosened or disturbed by the construction activities or materials which become
dry and desiccated or wet and softened should be removed and replaced prior to placement of
foundation concrete.
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EEC Project No. 1152119
December 14, 2015
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Seismic
The site soil conditions consist of approximately 2 to 7 feet of overburden cohesive subsoils
overlying poorly cemented to well-cemented sandstone bedrock. The building foundations will be
supported on the bedrock materials. For those site conditions, the 2012 International Building Code
indicates a Seismic Site Classification of C.
Lateral Earth Pressures
The proposed building will include a full-depth “walk-out/drive-out” basement as a part of the new
building. Site retaining walls may also be desirable with the grade changes across the site.
Basement walls of the building and/or site retaining walls would be subjected to lateral earth
pressures. Passive lateral earth pressures may help resist the driving forces for retaining wall or
other similar site structures. The values presented herein are for approved material placed and
compacted adjacent to the site structures.
Active lateral earth pressures could be used for design of structures where some movement of the
structure is anticipated, such as retaining walls. The total deflection of structures for design with
active earth pressure is estimated to be on the order of one half of one percent of the height of the
down slope side of the structure. We recommend at-rest pressures be used for design of structures
where rotation of the walls is restrained such as basement walls. Passive pressures and friction
between the footing and bearing soils could be used for design of resistance to movement of
retaining walls.
Coefficient values for backfill with the anticipated types of fill/backfill soil for calculation of active,
at-rest and passive earth pressures are provided in the table below. Equivalent fluid pressure is equal
to the coefficient times the appropriate soil unit weight. Those coefficient values are based on
horizontal backfill with backfill soils consisting of essentially granular materials and/or processed
sandstone bedrock with a friction angle of a 30 degrees or the site cohesive soils with a friction angle
of at least 20 degrees. For at-rest and active earth pressures, slopes down and away from the
structure would result in reduced driving forces with slopes up and away from the structures
resulting in greater forces on the walls. The passive resistance would be reduced with slopes away
from the wall. The top 30 inches of soil on the passive resistance side of walls could be used as a
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surcharge load; however, should not be used as a part of the passive resistance value. Frictional
resistance is equal to the tangent of the friction angle times the normal force. Surcharge loads or
point loads placed in or on the backfill can also create additional loads on below grade walls. Those
situations should be designed on an individual basis.
Soil Type Medium Dense Granular – On-
site or Approved Imported Fill Site Cohesive Subgrade Soils
Wet Unit Weight (pcf) 135 125
Saturated Unit Weight (pcf) 140 130
Friction Angle () – (assumed) 30° 20°
Active Pressure Coefficient 0.33 0.49
At-rest Pressure Coefficient 0.50 0.66
Passive Pressure Coefficient 3.00 2.04
The outlined values do not include factors of safety nor allowances for hydrostatic loads and are
based on assumed friction angles, which should be verified after potential material sources have
been identified. Care should be taken to develop appropriate drainage systems behind below grade
walls to eliminate potential for hydrostatic loads developing on the walls. Those systems would
likely include perimeter drain systems extending to sump areas or free outfall where reverse flow
cannot occur into the system. Where necessary, appropriate hydrostatic load values should be used
for design.
Floor Slab Subgrades
All existing vegetation/topsoil and existing site cohesive soils should be removed from beneath the
new building floor slab area(s). The subgrades should be prepared as outlined under the section
titled “Site Preparation” in this report. Floors could be supported directly on the placed structural
fill soils.
After preparation of the subgrades, care should be taken to avoid disturbing the subgrade materials.
Materials which are loosened or disturbed by the construction activities will require removal and
replacement or reworking in place prior to placement of the overlying floor slabs.
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Positive drainage should be developed away from the proposed building areas to avoid wetting the
subgrade or bearing materials. Subgrade or bearing materials allowed to become wetted subsequent
to construction can result in unacceptable performance of the improvements.
Pavement Subgrades
Within the pavement improvement areas, any existing vegetation/topsoil and/or any existing site
improvements should be removed. It is our opinion existing cohesive subgrade materials could
remain in-place beneath the new pavements below a depth of 2 feet below existing site grades. As a
minimum, the top 2 feet of cohesive subgrade material should be removed and replaced as a part of
the subgrade preparation. Moderately expansive in-situ soils suggest a potential for post-
construction heaving in areas where the cohesive materials remains in-place. The risk of future
heaving cannot be eliminated without removing and replacing the cohesive materials. We would be
pleased to discuss approaches to reducing the risk of future heaving in these areas if desired.
Fill materials required to develop the pavement subgrades should consist of approved, low-volume
change materials which are free from organic matter and debris. The site sandy lean clay near
surface soils or processed underlying sandstone bedrock could be used for fill in these areas. The
bedrock fill materials would better reduce the potential for post-construction heaving and reduce the
potential for unstable subgrade requiring stabilization for pavement construction. Fill materials
beneath any pavement improvement areas should be placed in loose lifts not to exceed 9 inches
thick, adjusted to with ±2% of optimum moisture content and compacted to at least 95% of the
material's standard Proctor maximum dry density.
After preparation of the subgrades, care should be taken to avoid disturbing the subgrade materials.
Materials which are loosened or disturbed by the construction activities will require removal and
replacement or reworking in place prior to placement of the overlying pavement sections.
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Pavement Design Sections
We expect the site pavements will be used predominately by automobile and light truck traffic with
possible access areas for heavier duty use such as trash trucks. Proofrolling and recompacting the
subgrade is recommended immediately prior to placement of the aggregate road base section. Soft or
weak areas delineated by the proofrolling operations should be undercut or stabilized in-place to achieve
the appropriate subgrade support.
If the cohesive site soils are used for fill beneath the pavements, stabilization of those materials could
be needed to develop stable subgrades for pavement construction. The site lean clays would be subject
to strength loss and instability/pumping of higher moisture contents. Stabilization, if required, might
include the incorporation of 12% Class C fly ash into the top 12 inches of the pavement subgrades.
Use of the reprocessed sandstone would increase stability of the subgrades and reduce the potential for
needing subgrade stabilization.
Pavement design methods are intended to provide structural sections with adequate thickness over a
particular subgrade such that wheel loads are reduced to a level the subgrade can support. The
support characteristics of the subgrade for pavement design do not account for long-term settlement
characteristics of the existing fill material. Thus, the pavement may be adequate from a structural
standpoint, yet still experience cracking and deformation due to related movement of the underlying
subsoils.
Recommended pavement sections are provided in the following table. The hot mix asphalt (HMA)
pavement should be grading S (75) or SX (75) with PG 58-28 oil. The aggregate base should be
Class 5 or Class 6 base. Portland cement concrete should be a pavement design mix with a
minimum 28-day compressive strength of 4,000 psi and should be air entrained. HMA pavements
may show rutting and distress in truck loading or turning areas. Concrete pavements should be
considered in those areas.
RECOMMENDED PAVEMENT SECTIONS
Automobile Parking Heavy Duty Areas
Hot Mix Asphalt (HMA)
Aggregate Base Course (ABC) – CDOT Class 5 or 6
4"
6"
5"
8"
PCC (Non-reinforced) 5” 6″
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The recommended pavement sections are minimums and periodic maintenance should be expected.
Longitudinal and transverse joints should be provided as needed in concrete pavements for
expansion/contraction and isolation. The location and extent of joints should be based upon the final
pavement geometry. Timing for cutting of control joints should be in accordance with ACI criteria. All
joints should be sealed to prevent entry of foreign material and dowelled where necessary for load
transfer.
Preventive maintenance should be planned and provided for through an on-going pavement
management program. Preventive maintenance activities are intended to slow the rate of pavement
deterioration, and to preserve the pavement investment. Preventive maintenance consists of both
localized maintenance (e.g. crack and joint sealing and patching) and global maintenance (e.g. surface
sealing). Preventive maintenance is usually the first priority when implementing a planned pavement
maintenance program and provides the highest return on investment for pavements. Prior to
implementing any maintenance, additional engineering observation is recommended to determine the
type and extent of preventive maintenance. Depending upon the final decision as to the extent and/or
limits for removal of the existing fill material, EEC can provide additional preventive maintenance
suggestions and/or recommendations upon request.
Site grading is generally accomplished early in the construction phase. However as construction
proceeds, the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, or
rainfall. As a result, the pavement subgrade may not be suitable for pavement construction and
corrective action will be required. The subgrade should be carefully evaluated at the time of pavement
construction for signs of disturbance, rutting, or excessive drying. If disturbance has occurred,
pavement subgrade areas should be reworked, moisture conditioned, and properly compacted to the
recommendations in this report immediately prior to paving. Overly wet subgrades could require
stabilization.
If during or after placement of the stabilization or initial lift of pavement, the area is observed to be
yielding under vehicle traffic or construction equipment, it is recommended that EEC be contacted
for additional alternative methods of stabilization, or a change in the pavement section.
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Other Considerations
Positive drainage should be developed away from the structure and pavement areas with a minimum
slope of 1 inch per foot for the first 10 feet away from the improvements in landscape areas. Care
should be taken in planning of landscaping adjacent to the building and parking and drive areas to
avoid features which would pond water adjacent to the pavement, foundations or stemwalls.
Placement of plants which require irrigation systems or could result in fluctuations of the moisture
content of the subgrade material should be avoided adjacent to site improvements. Lawn watering
systems should not be placed within 5 feet of the perimeter of the building and parking areas. Spray
heads should be designed not to spray water on or immediately adjacent to the structure or site
pavements. Roof drains should be designed to discharge at least 5 feet away from the structure and
away from the pavement areas.
Excavations into the on-site soils may encounter a variety of conditions. Excavations may encounter
loose and caving conditions. 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 and taking into account the site subsurface conditions as described
herein. 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.
Percolation Test Results
Soil-percolation tests were completed in percolation test holes located near borings B-8 and B-9 in
the proposed detention pond areas. At each location, the percolation tests were completed in
boreholes advanced to approximately 3 feet below ground surface which generally extended into the
sandy lean clay. A field slotted PVC piezometer was installed in each of the percolation test holes
prior to testing. After installation of the field slotted piezometers, the test holes were partially filled
with water to presoak the subgrades prior to testing. Approximately 24 hours after presoaking, EEC
performed the percolation tests by introducing water into the open boreholes and measuring the
water levels changes with time. The hydraulic gradient measured in the field was used to estimate
the percolation rate of the subsurface soils. The percolation test results are summarized in the
following table. The percolation rates generally reflect that of the new surface sandy lean clay in the
areas tested; we expect the underlying undisturbed bedrock would be relatively impermeable. The
percolation testing values do not include a factor of safety.
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Location Percolation Test Hole
Percolation Rate
(min/in)
Ave. Percolation Rate
(min/in)
B-8
1 16.4
2 18.7 16.0
3 13.0
B-9
1 34.7
2 13.0 20.9
3 15.0
GENERAL COMMENTS
The analysis and recommendations presented in this report are based upon the data obtained from
the soil borings performed at the indicated locations and from any other information discussed in this
report. This report does not reflect any variations which may occur between borings or across the
site. The nature and extent of such variations may not become evident until further exploration or
construction. If variations appear evident, it will be necessary to re-evaluate the recommendations
of this report.
It is recommended that the geotechnical engineer be retained to review the plans and specifications
so that comments can be made regarding the interpretation and implementation of our geotechnical
recommendations in the design and specifications. It is further recommended that the geotechnical
engineer be retained for testing and observations during earthwork and foundation construction
phases to help determine that the design requirements are fulfilled.
This report has been prepared for the exclusive use for representatives with Mr. Butch Stockover c/o
VFLA, for specific application to the project discussed and has been prepared in accordance with
generally accepted geotechnical engineering practices. No warranty, express or implied, is made. In
the event that any changes in the nature, design or location of the project as outlined in this report
are planned, the conclusions and recommendations contained in this report shall not be considered
valid unless the changes are reviewed and the conclusions of this report modified or verified in
writing by the geotechnical engineer.
Earth Engineering Consultants, LLC
DRILLING AND EXPLORATION
DRILLING & SAMPLING SYMBOLS:
SS: Split Spoon ‐ 13/8" I.D., 2" O.D., unless otherwise noted PS: Piston Sample
ST: Thin‐Walled Tube ‐ 2" O.D., unless otherwise noted WS: Wash Sample
R: Ring Barrel Sampler ‐ 2.42" I.D., 3" O.D. unless otherwise noted
PA: Power Auger FT: Fish Tail Bit
HA: Hand Auger RB: Rock Bit
DB: Diamond Bit = 4", N, B BS: Bulk Sample
AS: Auger Sample PM: Pressure Meter
HS: Hollow Stem Auger WB: Wash Bore
Standard "N" Penetration: Blows per foot of a 140 pound hammer falling 30 inches on a 2‐inch O.D. split spoon, except where noted.
WATER LEVEL MEASUREMENT SYMBOLS:
WL : Water Level WS : While Sampling
WCI: Wet Cave in WD : While Drilling
DCI: Dry Cave in BCR: Before Casing Removal
AB : After Boring ACR: After Casting Removal
Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils, the indicated
levels may reflect the location of ground water. In low permeability soils, the accurate determination of ground water levels is not
possible with only short term observations.
DESCRIPTIVE SOIL CLASSIFICATION
Soil Classification is based on the Unified Soil Classification
system and the ASTM Designations D‐2488. Coarse Grained
Soils have move than 50% of their dry weight retained on a
#200 sieve; they are described as: boulders, cobbles, gravel or
sand. Fine Grained Soils have less than 50% of their dry weight
retained on a #200 sieve; they are described as : clays, if they
are plastic, and silts if they are slightly plastic or non‐plastic.
Major constituents may be added as modifiers and minor
constituents may be added according to the relative
proportions based on grain size. In addition to gradation,
coarse grained soils are defined on the basis of their relative in‐
place density and fine grained soils on the basis of their
consistency. Example: Lean clay with sand, trace gravel, stiff
(CL); silty sand, trace gravel, medium dense (SM).
CONSISTENCY OF FINE‐GRAINED SOILS
Unconfined Compressive
Strength, Qu, psf Consistency
< 500 Very Soft
500 ‐ 1,000 Soft
1,001 ‐ 2,000 Medium
2,001 ‐ 4,000 Stiff
4,001 ‐ 8,000 Very Stiff
8,001 ‐ 16,000 Very Hard
RELATIVE DENSITY OF COARSE‐GRAINED SOILS:
N‐Blows/ft Relative Density
0‐3 Very Loose
4‐9 Loose
10‐29 Medium Dense
30‐49 Dense
50‐80 Very Dense
80 + Extremely Dense
PHYSICAL PROPERTIES OF BEDROCK
DEGREE OF WEATHERING:
Slight Slight decomposition of parent material on
joints. May be color change.
Moderate Some decomposition and color change
throughout.
High Rock highly decomposed, may be extremely
broken.
Group
Symbol
Group Name
Cu≥4 and 1<Cc≤3
E
GW Well-graded gravel
F
Cu<4 and/or 1>Cc>3
E
GP Poorly-graded gravel
F
Fines classify as ML or MH GM Silty gravel
G,H
Fines Classify as CL or CH GC Clayey Gravel
F,G,H
Cu≥6 and 1<Cc≤3
E
SW Well-graded sand
I
Cu<6 and/or 1>Cc>3
E
SP Poorly-graded sand
I
Fines classify as ML or MH SM Silty sand
G,H,I
Fines classify as CL or CH SC Clayey sand
G,H,I
inorganic PI>7 and plots on or above "A" Line CL Lean clay
K,L,M
PI<4 or plots below "A" Line ML Silt
K,L,M
organic Liquid Limit - oven dried Organic clay
K,L,M,N
Liquid Limit - not dried Organic silt
K,L,M,O
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 Organic clay
K,L,M,P
Liquid Limit - not dried Organic silt
K,L,M,O
Highly organic soils PT Peat
(D30)2
D10 x D60
GW-GM well graded gravel with silt NPI≥4 and plots on or above "A" line.
GW-GC well-graded gravel with clay OPI≤4 or plots below "A" line.
GP-GM poorly-graded gravel with silt PPI plots on or above "A" line.
GP-GC poorly-graded gravel with clay QPI plots below "A" line.
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
Earth Engineering Consultants, LLC
IIf soil contains >15% gravel, add "with gravel" to
group name
JIf Atterberg limits plots shaded area, soil is a CL-
ML, Silty clay
Unified Soil Classification System
1
2
B-7
B-6
B-3
B-2 B-1
B-4
B-5
B-9
B-8
Boring Location Diagram
JFK Luxury Apartments
Fort Collins, Colorado
EEC Project Number: 1152119 Date: November 2015
EARTH ENGINEERING CONSULTANTS, LLC
Approximate Boring
Locations
1
Legend
Site Photos
(Photos taken in approximate
location, in direction of arrow)
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
EEC PROJECT NO. 1152119
NOVEMBER 2015
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown 2
very stiff _ _
mottled 3
_ _
4
_ _ (% @ 150 psf)
CS 5 10 9000+ 14.0 110.5 31 15 51.8 800 psf 1.2%
_ _
6
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 7
brown / grey / rust _ _
moderately hard 8
_ _
9
_ _
SS 10 50/6" 2500 13.3
_ _
11
_ _
12
_ _
13
_ _
14
_ _
CS 15 50/5" 9000 13.5 106.4
_ _
16
_ _
17
_ _
18
_ _
19
_ _
SS 20 50/6" -- 13.5
_ _
21
_ _
22
_ _
23
_ _
24
_ _
SS 25 50/5.5" 9000+ 13.5 102.1
Continued on Sheet 2 of 2 _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
Continued from Sheet 1 of 2 26
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 27
brown / grey / rust _ _
moderately hard 28
_ _
29
_ _
SS 30 50/3" -- 7.3
_ _
31
_ _
32
_ _
33
_ _
34
_ _
CS 35 50/4" 9000+ 12.0 99.5
BOTTOM OF BORING DEPTH 35.0' _ _
36
_ _
37
_ _
38
_ _
39
_ _
40
_ _
41
_ _
42
_ _
43
_ _
44
_ _
45
_ _
46
_ _
47
_ _
48
_ _
49
_ _
50
_ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
N/A
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown 2
very stiff _ _ (% @ 150 psf)
CS 3 22 9000+ 8.1 108.8 40 23 69.4 2200 psf 6.5%
_ _
4
_ _
SANDSTONE / SILTSTONE SS 5 23 5500 9.9
brown / grey / rust _ _
poorly cemented 6
_ _
7
_ _
8
_ _
9
_ _
CS 10 50/7" 9000 13.9 120.0
_ _
11
_ _
12
_ _
13
_ _
14
_ _
SS 15 50/5" -- 12.2
_ _
16
_ _
17
_ _
18
_ _
19
_ _
CS 20 50/4" 9000+ 10.3 118.1
_ _
21
_ _
22
_ _
23
_ _
24
_ _
SS 25 50/7" 3000 12.6
BOTTOM OF BORING DEPTH 25.5' _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown 2
_ _
3
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 4
brown / grey / rust _ _
moderately hard CS 5 50/11" -- 12.9
_ _
6
_ _
7
_ _
8
_ _
9
_ _
SS 10 50/9" 2500 14.4
_ _
11
_ _
12
_ _
13
_ _
14
_ _
CS 15 50/6" 9000+ 13.5 106.6 32 7 35.8 1000 psf 0.1%
_ _
16
_ _
17
_ _
18
_ _
19
_ _
SS 20 50/5" 1000 13.8
_ _
21
_ _
22
_ _
23
_ _
24
_ _
CS 25 50/4" 4500 13.2
Continued on Sheet 2 of 2 _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
Continued from Sheet 1 of 2 26
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 27
brown / grey / rust _ _
moderately hard 28
_ _
29
_ _
SS 30 50/4" 2000 12.5
_ _
31
_ _
32
_ _
33
_ _
34
_ _
CS 35 50/3" -- 12.1
BOTTOM OF BORING DEPTH 35.0' _ _
36
_ _
37
_ _
38
_ _
39
_ _
40
_ _
41
_ _
42
_ _
43
_ _
44
_ _
45
_ _
46
_ _
47
_ _
48
_ _
49
_ _
50
_ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
N/A
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
SANDY LEAN CLAY (CL) 1
brown _ _
2
_ _
SANDSTONE / SILTSTONE / CLAYSTONE CS 3 50/11" 9000+ 7.2 120.4
brown/grey/rust _ _
moderately hard 4
_ _
SS 5 50/6" 6000 5.6
_ _
6
_ _
7
_ _
8
_ _
9
_ _
CS 10 50/6" 9000+ 13.3 122.1 45.5 1600 psf 0.8%
_ _
11
_ _
12
_ _
13
_ _
14
_ _
SS 15 50/7" 1500 14.6
_ _
16
_ _
17
_ _
18
_ _
19
_ _
CS 20 50/6" 9000+ 15.3 112.5
_ _
21
_ _
22
_ _
23
_ _
24
_ _
SS 25 50/5" -- 13.4
BOTTOM OF BORING DEPTH 25.5' _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown / grey / rust 2
very stiff _ _
3
_ _
4
_ _ (% @ 150 psf)
CS 5 13 8500 16.5 110.6 37 22 71.6 1100 psf 1.9%
_ _
6
_ _
7
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 8
brown / grey / rust _ _
poorly cemented / highly weathered 9
less weathered with depth _ _
SS 10 40 5000 16.2
_ _
11
_ _
12
_ _
13
_ _
14
_ _
CS 15 50/6" 9000 12.4 117.6
_ _
16
_ _
17
_ _
18
cemented lenses _ _
19
_ _
SS 20 50/4" 6000 8.6
_ _
21
_ _
22
_ _
23
_ _
24
_ _
CS 25 50/6" 9000+ 15.4 112.2
BOTTOM OF BORING DEPTH 25.0' _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown 2
_ _
3
_ _
4
_ _
SANDSTONE / SILTSTONE / CLAYSTONE CS 5 38 9000+ 11.7 119.5 33 14 51.4 1600 psf 0.9%
highly weathered / poorly cemented _ _
moderately hard 6
_ _
7
_ _
8
_ _
9
_ _
SS 10 50/10" 4500 11.3
_ _
11
_ _
12
_ _
13
_ _
SANDSTONE 14
grey / brown / rust _ _
poorley cemented CS 15 50/2" -- 4.9
_ _
16
_ _
17
_ _
18
_ _
19
_ _
SANDSTONE / SILTSTONE / CLAYSTONE SS 20 50/6" 3000 11.9
brown / grey / rust _ _
moderately hard 21
_ _
22
_ _
23
_ _
24
_ _
CS 25 50/6" 9000+ 12.7 116.7
BOTTOM OF BORING DEPTH 25.0' _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown / rust 2
very stiff _ _ (% @ 150 psf)
with calcareous deposits CS 3 16 9000+ 8.2 110.8 35 19 55.4 3200 psf 6.5%
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 4
brown / grey / rust _ _
poorly cemented / highly weathered SS 5 21 9000+ 12.0
less weathered with depth _ _
6
_ _
7
_ _
8
_ _
9
_ _
CS 10 50/7" 9000+ 13.5 119.9 33 14 48.4 1100 psf 0.5%
_ _
11
_ _
12
_ _
13
_ _
14
_ _
SS 15 50/6" 1500 13.9
_ _
16
_ _
17
_ _
18
_ _
19
_ _
CS 20 50/5.5" 9000+ 13.8 110.0
_ _
21
_ _
22
_ _
23
_ _
24
_ _
SS 25 50/6" -- 13.4
BOTTOM OF BORING DEPTH 25.5' _ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown 2
_ _
SANDSTONE / SILTSTONE / CLAYSTONE SS 3 50 9000+ 6.8
brown / rust / grey _ _
4
_ _
5
_ _
6
_ _
7
_ _
8
_ _
9
_ _
SS 10 50 4500 15.9
_ _
BOTTOM OF BORING DEPTH 10.5' 11
_ _
12
_ _
13
_ _
14
_ _
15
_ _
16
_ _
17
_ _
18
_ _
19
_ _
20
_ _
21
_ _
22
_ _
23
_ _
24
_ _
25
_ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
DATE:
RIG TYPE: CME55
FOREMAN: DG
AUGER TYPE: 4" CFA
SPT HAMMER: AUTOMATIC
SOIL DESCRIPTION D N QU MC DD -200
TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF
TOPSOIL & VEGETATION _ _
1
SANDY LEAN CLAY (CL) _ _
brown 2
very stiff _ _
with calcareous deposits SS 3 7 9000+ 8.3
_ _
4
_ _
5
_ _
6
_ _
SANDSTONE / SILTSTONE / CLAYSTONE 7
brown / rust _ _
moderately hard 8
_ _
9
_ _
SS 10 50 7000 14.1
_ _
BOTTOM OF BORING DEPTH 10.5' 11
_ _
12
_ _
13
_ _
14
_ _
15
_ _
16
_ _
17
_ _
18
_ _
19
_ _
20
_ _
21
_ _
22
_ _
23
_ _
24
_ _
25
_ _
Earth Engineering Consultants, LLC
A-LIMITS SWELL
Project:
Location:
Project #:
Date:
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Clay
Sample Location: Boring 1, Sample 1, Depth 4'
Liquid Limit: 31 Plasticity Index: 15 % Passing #200: 51.8%
Beginning Moisture: 14.0% Dry Density: 102.3 pcf Ending Moisture: 21.5%
Swell Pressure: 800 psf % Swell @ 150: 1.2%
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Clay
Sample Location: Boring 2, Sample 1, Depth 2'
Liquid Limit: 40 Plasticity Index: 23 % Passing #200: 69.4%
Beginning Moisture: 8.1% Dry Density: 111 pcf Ending Moisture: 21.1%
Swell Pressure: 2200 psf % Swell @ 150: 6.5%
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
Beginning Moisture: 13.5% Dry Density: 111.3 pcf Ending Moisture: 18.7%
Swell Pressure: 1000 psf % Swell @ 500: 0.1%
Sample Location: Boring 3, Sample 3, Depth 14'
Liquid Limit: 32 Plasticity Index: 7 % Passing #200: 35.8%
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown / Grey / Rust Sandstone / Siltstone / Claystone
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown/Grey/Rust Sandstone/Siltstone/Claystone
Sample Location: Boring 4, Sample 3, Depth 9'
Liquid Limit: - - Plasticity Index: - - % Passing #200: 45.5%
Beginning Moisture: 13.3% Dry Density: 117.3 pcf Ending Moisture: 16.1%
Swell Pressure: 1600 psf % Swell @ 500: 0.8%
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Clay
Sample Location: Boring 5, Sample 1, Depth 4'
Liquid Limit: 37 Plasticity Index: 22 % Passing #200: 71.6%
Beginning Moisture: 16.5% Dry Density: 109 pcf Ending Moisture: 19.3%
Swell Pressure: 1100 psf % Swell @ 150: 1.9%
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
Beginning Moisture: 11.7% Dry Density: 112.9 pcf Ending Moisture: 19.0%
Swell Pressure: 1600 psf % Swell @ 500: 0.9%
Sample Location: Boring 6, Sample 1, Depth 4'
Liquid Limit: 33 Plasticity Index: 14 % Passing #200: 51.4%
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown/Grey/Rust Sandstone/Siltstone/Claystone
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Clay
Sample Location: Boring 7, Sample 1, Depth 2'
Liquid Limit: 35 Plasticity Index: 19 % Passing #200: 55.4%
Beginning Moisture: 8.2% Dry Density: 118.1 pcf Ending Moisture: 17.6%
Swell Pressure: 3200 psf % Swell @ 150: 6.5%
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
Project:
Location:
Project #:
Date:
JFK Luxury Apartments
Fort Collins, Colorado
1152119
December 2015
Beginning Moisture: 13.5% Dry Density: 115.9 pcf Ending Moisture: 16.6%
Swell Pressure: 1100 psf % Swell @ 500: 0.5%
Sample Location: Boring 7, Sample 3, Depth 9'
Liquid Limit: 33 Plasticity Index: 14 % Passing #200: 48.4%
SWELL / CONSOLIDATION TEST RESULTS
Material Description: Brown/Grey/Rust Sandstone/Siltstone/Claystone
-10.0
-8.0
-6.0
-4.0
-2.0
0.0
2.0
4.0
6.0
8.0
10.0
0.01 0.1 1 10
Percent Movement
Load (TSF)
Consolidatio Swell
Water Added
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-9 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-8 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-7 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-6 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-5 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR 14.5'
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-4 DECEMBER 2015
11/24/2015 AFTER DRILLING N/A
SURFACE ELEV 24 HOUR N/A
FINISH DATE
SHEET 2 OF 2 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-3 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 2 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-3 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR N/A
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 1 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-2 DECEMBER 2015
11/24/2015 AFTER DRILLING N/A
SURFACE ELEV 24 HOUR 11.5'
FINISH DATE
SHEET 2 OF 2 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-1 DECEMBER 2015
SURFACE ELEV N/A 24 HOUR 11.5'
FINISH DATE 11/24/2015 AFTER DRILLING N/A
SHEET 1 OF 2 WATER DEPTH
START DATE 11/24/2015 WHILE DRILLING None
JFK LUXURY APARTMENTS
FORT COLLINS, COLORADO
PROJECT NO: 1152119 LOG OF BORING B-1 DECEMBER 2015
Soil Classification
Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests
Sands 50% or more
coarse fraction
passes No. 4 sieve
Fine-Grained Soils
50% or more passes
the No. 200 sieve
<0.75 OL
Gravels with Fines
more than 12%
fines
Clean Sands Less
than 5% fines
Sands with Fines
more than 12%
fines
Clean Gravels Less
than 5% fines
Gravels more than
50% of coarse
fraction retained on
No. 4 sieve
Coarse - Grained Soils
more than 50%
retained on No. 200
sieve
CGravels with 5 to 12% fines required dual symbols:
Kif soil contains 15 to 29% plus No. 200, add "with sand"
or "with gravel", whichever is predominant.
<0.75 OH
Primarily organic matter, dark in color, and organic odor
ABased on the material passing the 3-in. (75-mm)
sieve
ECu=D60/D10 Cc=
HIf fines are organic, add "with organic fines" to
group name
LIf soil contains ≥ 30% plus No. 200 predominantly sand,
add "sandy" to group name.
MIf soil contains ≥30% plus No. 200 predominantly gravel,
add "gravelly" to group name.
DSands with 5 to 12% fines require dual symbols:
BIf field sample contained cobbles or boulders, or
both, add "with cobbles or boulders, or both" to
group name. FIf soil contains ≥15% sand, add "with sand" to
GIf fines classify as CL-ML, use dual symbol GC-
CM, or SC-SM.
Silts and Clays
Liquid Limit less
than 50
Silts and Clays
Liquid Limit 50 or
more
0
10
20
30
40
50
60
0 10 20 30 40 50 60 70 80 90 100 110
PLASTICITY INDEX (PI)
LIQUID LIMIT (LL)
ML OR OL
MH OR OH
For Classification of fine-grained soils and
fine-grained fraction of coarse-grained
soils.
Equation of "A"-line
Horizontal at PI=4 to LL=25.5
then PI-0.73 (LL-20)
Equation of "U"-line
Vertical at LL=16 to PI-7,
then PI=0.9 (LL-8)
CL-ML
HARDNESS AND DEGREE OF CEMENTATION:
Limestone and Dolomite:
Hard Difficult to scratch with knife.
Moderately Can be scratched easily with knife.
Hard Cannot be scratched with fingernail.
Soft Can be scratched with fingernail.
Shale, Siltstone and Claystone:
Hard Can be scratched easily with knife, cannot be
scratched with fingernail.
Moderately Can be scratched with fingernail.
Hard
Soft Can be easily dented but not molded with
fingers.
Sandstone and Conglomerate:
Well Capable of scratching a knife blade.
Cemented
Cemented Can be scratched with knife.
Poorly Can be broken apart easily with fingers.
Cemented