HomeMy WebLinkAbout20141220.tiff SUBSURFACE EXPLORATION REPORT
BILL BARRETT FIELD OFFICE
SH 392 & CR 33
WELD COUNTY,COLORADO
EEC PROJECT NO. 1132085
Prepared for:
Lamar Construction Company
4025 Saint Cloud Drive, Suite 150
Loveland, Colorado 80538
Attn: Mr. Dan Dirksen (ddirksen@lamarconstruction.com)
Prepared by:
Earth Engineering Consultants, LLC
4396 Greenfield Drive
Windsor, Colorado 80550
EARTH ENGINEERING
November 12, 2013 CONSULTANTS, LLC
Lamar Construction Company
4025 Saint Cloud Drive, Suite 150
Loveland, Colorado 80538
Attn: Mr. Dan Dirksen (ddirksen(cr�,lamarconstruction.com)
Re: Subsurface Exploration Report
Bill Barrett Field Office
SH 392 &WCR 33
Weld County, Colorado
EEC Project No. 1132085
Mr. Dirksen:
Enclosed, herewith, are results of the geotechnical subsurface exploration completed by
Earth Engineering Consultants, LLC (EEC) personnel for the referenced project. This
project was completed in general accordance with our proposal dated October 22, 2013.
We understand this project involves the construction of an approximate 12,000 square-
foot plan area building northwest of the intersection of SH 392 and CR 33 in Weld
County. Site pavements are expected to be constructed adjacent to the east and west
sides of the new building. A future addition of similar floor area is planned to the north
of the new facility.
To develop information on existing subsurface conditions in the area of the proposed
facility, EEC personnel advanced seven(7) soil borings. Those borings were advanced to
depths of approximately 10 feet below present ground surface in four (4) pavement area
borings and 20 feet in three (3) building area borings. The subgrade materials observed
in the test borings generally consisted of sandy lean clay underlain at depths of 18 to 19
feet by sandstone bedrock. The near surface sandy lean clay soils were generally soft to
medium stiff while the underlying bedrock was moderately hard. Groundwater was
observed at approximately 10 feet below ground surface at the time of drilling.
4396 GREENFIELD DRIVE
WINDSOR, COLORADO 80550
(970) 545-3908 rAX (970) 663-0282
Earth Engineering Consultants,LLC
EEC Project No. 1132085
November 12,2013
Page 2
In our opinion, a portion of the soft lean clay soils immediately beneath the planned
building foundations should be over-excavated and replaced with a granular structural fill
to increase support strength and reduce the potential for large post-construction
settlement of the new building foundations. Following the overexcavation and backfill
procedure outlined in the attached report, in our opinion, the building could then be
supported on conventional footing foundations bearing on the placed structural fill.
Reconditioned and compacted near surface site soils appear usable (without over-
excavation) for support of the new floor slab and site pavements; although, fly ash
stabilization of the pavement subgrades should be expected with the site cohesive soil
subgrades.
Geotechnical recommendations concerning design and construction of the proposed
building and support of site pavements are included in the attached report. If you have
any questions regarding the enclosed report, or if we can be of further service to you in
any other way,please do not hesitate to contact us.
Very truly yours,
Earth Engineering Cot sultants, LLC
4,
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�11 rj
Ethan P. Wiechert, P.E.
Senior Project Engineer
Reviewed by: Lester L. Litton, P.E.
Principal Engineer
SUBSURFACE EXPLORATION REPORT
BILL BARRETT FIELD OFFICE
SH 392 & CR 33
WELD COUNTY, COLORADO
EEC PROJECT NO. 1132085
November 12, 2013
INTRODUCTION
The geotechnical subsurface exploration requested for the proposed office/shop building and
associated site pavements to be constructed on Lot C of the recorded exemption No. 0805-
15-04 RECX 13-0066 located northwest of the intersection of SH 392 and CR 33 in Weld
County, Colorado, has been completed. As part of the exploration, seven (7) soil borings
were advanced in the improvement area to evaluate existing subsurface conditions. Three
(3)borings were advanced within proposed building areas to depths of approximately 20 feet
below ground surface and four (4)borings were advanced in pavement areas to depths of
approximately 10 feet. One (1) profile boring and six (6) shallow percolation holes were
drilled in a proposed septic leach field area. The percolation testing and septic design will be
completed by others. Individual boring logs and a diagram indicating the approximate
boring locations are included with report.
We understand the new office/shop building will be constructed at the northwest corner of
the intersection of SH 392 and CR 33 approximately 7 miles east of Windsor in Weld
County. The new building is expected to be a steel framed metal building with a slab-on-
grade floor. The plan area of the building will be approximately 12,000 square feet with
plans for a similar size future addition to the north. We expect light foundation loads with
individual column loads less than100 kips and continuous wall loads less than 2.5 kips per
lineal foot. Floor loads are expected to be light. Cuts and/or fills on the site are expected to
be minimal. Site pavements will be constructed immediately to the east and west of the new
building. A diagram indicating the anticipated site layout is included with this report.
The purpose of this report is to describe the subsurface conditions encountered in the test
borings, analyze and evaluate the test data and provide geotechnical recommendations for
design and construction of the building foundations and support of floor slabs and site
pavements.
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 2
EXPLORATION AND TESTING PROCEDURES
The boring locations were selected and established in the field by representatives of Earth
Engineering Consultants,LLC(EEC)by pacing and estimating angles from identifiable site
references. Those approximate boring locations are indicated on the attached boring location
diagram. The locations of the borings should be considered accurate only to the degree
implied by the methods used to make the field measurements.
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 in the test borings were obtained using split-barrel and California
barrel sampling techniques 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 split barrel and California barrel 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.
Laboratory moisture content tests were completed on each of the recovered samples. The
unconfined strength of appropriate samples was estimated using a calibrated hand
penetrometer. Atterberg limits and washed sieve analysis tests were completed to determine
plasticity and quantity of fines in the subgrades. Swell/consolidation tests were completed
on selected samples to evaluate volume change with increased moisture content and load.
Results of the outlined tests are indicated on the attached boring logs and summary sheets.
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 3
As part of the testing program,all samples were examined in the laboratory and classified in
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 evaluation of auger cuttings and disturbed samples. Coring and/or
petrographic analysis may reveal other rock types.
SITE AND SUBSURFACE CONDITIONS
The project site is located on an undeveloped parcel at the northwest corner of the
intersection of SH 392 and CR 33 in Weld County. The proposed building area was
relatively flat and covered with sparse vegetation at the time of drilling. Site photos taken at
the time of our drilling operations are attached with this report.Based on results of the field
borings and laboratory testing, subsurface conditions can be generalized as follows.
The surficial materials described above were generally underlain by dark brown and brown
sandy lean clay which extended to depths of approximately 18 to 19 feet below ground
surface in the building area borings(B-5, B-6 and B-7)and to the bottom of the remaining
borings at depths of approximately 10 to 15 feet. The sandy lean clay soils were relatively
moist and generally soft to medium stiff in consistency. In laboratory swell/consolidation
testing,the sandy lean clay exhibited low swelling when inundated under a 150 psf surcharge
pressure and no swelling when inundated with water under a 500 psf surcharge pressure.
However,the sandy lean clay exhibited moderate consolidation within increases in loading.
The sandy lean clay was underlain by sandstone bedrock which extended to the bottom of
the completed test boings in the building area at depths of approximately 20 feet below
ground surface. The sandstone bedrock was generally moderately hard to hard.
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.
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 4
GROUNDWATER CONDITIONS
Observations were made while drilling and after completion of the borings to detect the
presence and depth to hydrostatic groundwater. During drilling,free water was observed at
depths of approximately 10 feet in the completed test borings.The boreholes were backfilled
upon completion of drilling and, thus, further observation of groundwater levels was not
completed.
Fluctuations in groundwater levels can occur over time depending on variations in
hydrologic conditions, such as the presence and level of water in nearby reservoirs and
supply canals, and other conditions not apparent at the time of this report. Perched and/or
trapped groundwater may occur at periods throughout the year in more permeable zones
within the subgrade materials. The location and amount of perched/trapped water can also
vary over time depending on variations in hydrologic conditions and other conditions not
apparent at the time of this report.
ANALYSIS AND RECOMMENDATIONS
Site Preparation
To develop the new building and roadway areas,we recommend any existing vegetation and/or
topsoil encountered in these areas be removed. After stripping and completing all cuts and
prior to placement of any fill and/or site improvements,we recommend the exposed subgrades
be scarified to a minimum depth of 9 inches,adjusted in 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. The moisture content of the scarified soils
should be adjusted to be within the range of±2% of standard Proctor optimum moisture
content. During preparation of the subgrades, care should be taken to identify any soft or
unstable areas. Areas showing instability should be reworked and/or removed and replaced
with suitable fill material as outlined below.
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 5
Fill soils necessary to develop the building and pavement subgrades should consist of
approved,low-volume-change materials,which are free from organic matter and debris. It is
our opinion the near surface lean clay soils could be used; however, those soils were very
moist at the time our drilling operations and would likely require some drying prior to use as
fill. Consideration could also be given to importing a fill material. If fill materials are
imported,we recommend fill materials consist of an essentially granular material similar to
CDOT Class 5, 6 or 7 aggregate bases.
We recommend fill soils within building and pavement areas be placed in loose lifts not to
exceed 9 inches thick, 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. If the
site sandy lean clay soils are used, care will be needed to maintain the recommended
moisture contents of the soil prior to and during construction of overlying improvements.
Foundations
At the time of our drilling operations,the sandy lean clay subgrade soils were very moist and
generally soft to medium stiff in consistency. Laboratory testing on relatively undisturbed
samples of the sandy lean clay indicted that at current moisture and density conditions,those
soils would exhibit moderate volume changes(consolidation) with increases in loading. As
such,we expect improvements supported directly on the natural lean clay soils could settle an
appreciable amount subsequent to construction. To reduce the potential for settlement and
increase the support capacity,we recommend a zone of natural sandy lean clay soils below the
planned foundation footings be over-excavated and replaced with a granular, low volume
change structural fill material. Recommendations for developing foundation support to reduce
the post-construction settlement of the new addition are as follows.
To reduce the potential for settlement of the new building foundations,we recommend over-
excavating a zone at least 2 feet of soil beneath the planned foundation footings and
replacing that soil with a low volume change granular structural fill. The over-excavation
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 6
should extend laterally in all directions from the footing edges at least 8 inches for every 12
inches of over-excavation depth.
Once the over-excavation is completed, we recommend an approved, low-volume change
granular material is used to redevelop bearing elevations. The granular backfill material
should be graded similar to a CDOT Class 5,6 or 7 aggregate bases. Recycled concrete base
materials graded to Class 5 or Class 6 grain size could be used. The backfill materials
should adjusted to a workable 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.
If excessively wet/soft lean clay soils are encountered at the base of the overexcavations,we
recommend placement/compaction of a larger size crushed aggregate be considered to
develop an initial working platform for the structural fill.
Based on the site conditions and the recommendations outlined above, in our opinion the
proposed lightly loaded structure for this site could be supported on conventional footing
foundations bearing on a zone of granular structural fill. For design of footing foundations
bearing a zone of granular fill as outlined above,we recommend using a net allowable total
load soil bearing pressure not to exceed 1,500 psf. The net bearing pressure refers to the
pressure at foundation bearing level in excess of the minimum surrounding overburden
pressure. Total load should include full dead and live loads.
Exterior foundations and foundations in unheated areas should be located at least 30 inches
below adjacent exterior grade to provide frost protection. We recommend formed
continuous footings have a minimum width of 12 inches and isolated column foundations
have a minimum width of 24 inches.
No unusual problems are anticipated in completing the excavations required for construction
of the footing foundations. 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
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 7
removed and replaced prior to placement of foundation concrete. We estimate the total
settlement of the new foundations may be on the order of 1 inch.
Floor Slabs
Based on the materials observed in our site exploration,in our opinion floor slab subgrades
prepared as recommended in the section titled Site Preparation could be used to support the
floor slab (over-excavation to develop floor slab support would not be necessary). For the
subgrade prepared as outlined,we recommend the floor slab be designed using a modulus of
subgrade reaction of 75 pounds per cubic inch(pci).
Pavements
We anticipate the new pavements will be used predominantly by low volumes of automobile
and/or light truck traffic with occasional heavier trucks. Based on the expected traffic
volumes, we estimate an equivalent daily load allowance (EDLA) rating of 5. We
recommend the pavement subgrades be prepared as recommended in the section titled Site
Preparation. We estimate a subgrade support R-value of 5 for the site sandy lean clay.
Prior to placement of aggregate base,we recommend proof rolling the pavement subgrade to
identify any soft,wet and yielding areas. Yielding and/or soft areas in the subgrade should
be reworked and/or replaced prior to placement of aggregate base materials. The lean clay
soils are subject to strength loss and instability when wetted. If the subgrades become
wetted prior to pavement construction, moderate to significant pumping of the subgrades
may occur. Stabilization of the subgrades could become necessary to develop stable
subgrades for paving. Stabilization of the subgrades could be considered as a part of the up-
front design. An alternative pavement section including a stabilized subgrade is provided in
Table 1. Stabilization with Class C fly ash would generally include the addition of 12%fly
ash by dry weights within the top 12 inches of the subgrades. Additional recommendations
for pavement subgrade stabilization, including alternative materials,can be provided upon
request.
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 8
For the outlined conditions,the recommended site pavement sections are summarized below
in Table 1. The recommended pavement sections are minimums, as such, periodic
maintenance should be expected.
Table 1. Recommended pavement sections for the low volume pavement section.
EDLA 5
Reliability 75%
Resilient Modulus 3025 psi
PSI Loss 2.5
Design Structure Number 2.48
Hot Mix Asphalt 4"
Aggregate Base 6"
(Design Structural Number) (2.42)
Hot Mix Asphalt 3"
Aggregate Base 4"
Stabilized Subgrade 12"
(Design Structural Number) (2.36)
PCC(Non-reinforced) 5"
The aggregate base to develop the pavement section should consist of CDOT Class 5 or
Class 6 aggregate base. The aggregate base materials should be placed and compacted to
achieve a minimum of 95% of standard Proctor maximum dry density.
Hot mix asphalt(HMA)used to develop the pavement should be grading S(75)or SX(75)
with PG 64-22 or PG 58-28 asphalt binder. HMA should be compacted to within 92 to 96%
of the material's maximum theoretical specific gravity.
Portland cement concrete should be an approved pavement mix with a minimum 28-day
compressive strength of 4,000 psi and should be air entrained. Concrete pavements should
be considered in areas where heavy trucks(e.g.truck loading/unloading areas,trash trucks)
or truck turning areas.
The recommended pavement sections are based on assumed traffic conditions. If the
anticipated traffic loads vary significantly from that assumed, EEC should be contacted to
review the traffic conditions and provide alternative recommendations if appropriate.
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 9
Other Considerations
Positive drainage should be developed away from the new structure and across and away
from the edges of the site pavements. Water allowed to pond on or adjacent to the
pavements or adjacent to the building can result in poor performance of those improvements.
Care should be taken when planning landscaping adjacent to the structure to avoid features
which could pond water adjacent to the foundations or stem walls. Roof drains should be
designed to discharge at least 5 feet away from the structures and away from the pavement
areas.
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 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 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 of Lamar Construction Company 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
Earth Engineering Consultants,LLC
EEC Project No. 1132085
Bill Barrett Field Office
November 12,2013
Page 10
report shall not be considered valid unless the changes are reviewed and the conclusions of
this report are modified or verified in writing by the geotechnical engineer.
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
DEGREE OF WEATHERING:
Soil Classification is based on the Unified Soil Classification Slight Slight decomposition of parent material on
system and the ASTM Designations D-2488. Coarse Grained joints. May be color change.
Soils have move than 50%of their dry weight retained on a#200 Moderate Some decomposition and color change
sieve;they are described as: boulders,cobbles,gravel or sand. throughout.
Fine Grained Soils have less than 50% of their dry weight High Rock highly decomposed,may be extreme!
retained on a#200 sieve;they are described as: clays,if they broken.
are plastic, and silts if they are slightly plastic or non-plastic. HARDNESS AND DEGREE OF CEMENTATION:
Major constituents may be added as modifiers and minor Limestone and Dolomite:
constituents may be added according to the relative proportions Hard Difficult to scratch with knife.
based on grain size. In addition to gradation, coarse grained Moderately Can be scratched easily with knife.
soils are defined on the basis of their relative in-place density
and fine grained soils on the basis of their consistency. Hard Cannot be scratched with fingernail.
Example: Lean clay with sand, trace gravel, stiff(CL); silty Soft Can be scratched with fingernail.
sand,trace gravel,medium dense(SM).
Shale.Siltstone and Claystone:
CONSISTENCY OF FINE-GRAINED SOILS Hard Can be scratched easily with knife,cannot be
scratched with fingernail.
Unconfined Compressive Moderately Can be scratched with fingernail.
Strength,Qu,psf Consistency Hard
Soft Can be easily dented but not molded with
< 500 Very Soft fingers.
500- 1,000 Soft Sandstone and Conglomerate:
1,001 - 2,000 Medium Well Capable of scratching a knife blade.
2,001 - 4,000 Stiff Cemented
4,001 - 8,000 Very Stiff Cemented Can be scratched with knife.
8,001 - 16,000 Very Hard
Poorly Can be broken apart easily with fingers.
RELATIVE DENSITY OF COARSE-GRAINED SOILS: Cemented
N-Blows/ft Relative Density
0-3 Very Loose
4-9 Loose
10-29 E E C
Medium Dense
30-49 Dense
50-80 Very Dense
80+ Extremely Dense
PHYSICAL PROPERTIES OF BEDROCK
UNIFIED SOIL,C L ASSIIIFIECATI«N SYSTEM
Soil Classification
Group Group Name
Criteria for Assigning Group Symbols and Group names Using Laboratory Tests Symbol
Coarse—Grained Gravels more than Clean Gravels Less
Soils more than 50% of coarse than 5% fines Cu>4 and <Cc<3` GW Well—graded gravely
50% retained an fraction retained
• No. 200 sieve on No. 4 sieve Cu<4 and/or 1>Cc>3` GP Poorly—graded grovels
Gravels with Fines Fines classify as ML or MH GM Silty gravel, G,H
more than 12%
fines Fines classify as CL or CH CC Clayey Gravely'`•"
Sands 50% or Clean Sands Less Cu>.5 and l<C-c≤3` SW Well—graded sand'
• mare coarse than 5% fines
fraction passes Cu<6 and/or 1>Cc>3` SP Poorly—graded sand'
No. 4 sieve
Sands with Fines Fines classify as ML or MH SM Silty sand`'
more than 12%
fines Fines classify as CL or CH SC Clayey sand""'
Fine—Grained Silts and Clays inorganic PI>7 and plots on or above -A-Line CL Lean clay.'"
Soils 50% or Liquid Limit less
more posses the than 50 PI<4 or plots below -Aline' ML Silt"'
No. 200 sieve
organic Liquid limit — oven dried Organic clay&L
<0.75 OL
liquid Limit — not dried Organic silt"-"'
Silts and Clays inorganic PI plots on or obove "A"Line CH Fat clay'
Liquid Limit 50 or
more PI plots below "A"Line MH Elastic Silt`'"
organic Liquid Limit — oven dried Organic clay.'"
<0.75 OH
Liquid Limit — not dried Organic silt"-"
Highly organic soils Primarily organic matter, dark in calor, and organic odor PT Peat
%Bused on the material passing the 3-in. (75- 0CU=D�D Cc= 5(1:1?—O- EIf sod contains 15 to 29%plus No. 200, add
mm) sieve 1 "with sond" or "with grovel". whichever is
°If field sample contained cobbles or boulders, predotnlnanL
or both, odd "with cobbles or boulders, or both" L1f sot contains 2 30" plus No. 200
to group nom r11 sot contains 215% sand, add"with•sond"lo predominantly sand, odd "sandy to group
°Grovels with 5 to 12% Fines required dual name.
symbols group name. "If soil contains 2 30% plus No. 200
GW-GM well graded grovel with silt cl( CM, classify os CL-ML, use dual symbol predominantly 9 "gravely" group
GC-CM, r s a redominontl ravel, add ravel to you
GW-CC well-graded gravel with clay of Fines ore organic, add-with organic Fines to Nome'
GP-GM poorly-graded grovel with silt PI24 and plots on or above "A" line.
GP-GC poorly-graded gravel with cloy group name °Pi�4 or plots below "A" line.
°Sands with 5 to 12% fines require dual If contains >i5Xyrovel, add-with grovel" r plots lots on or above "A" line.
s bols: to group name. oPl plots below "A" line.
'If Atteruerg limits plots shaded area, sat is a
SW-SM well-graded sand with silt
SW-SC well-graded sand with cloy CL-ML, cilty cloy.
SP-SM poorly graded sand with silt
SP-SC poorly graded sand with clay
50
For['ossification of nne-grained loos ..I
and f grainrd traction of coorsr f- /
groincd soil:
I
-
so Equation of"A'—tins i '
,, llorvoeta of A"4 ID LL-75.5, c'
4.
then PI-0.73(LL-20) �,.i O • S°
d Equation of V-Me '��
40- Vertical et LL"I6 to PI=7, •I`
tX Wm PI�0.9(LL-6) .� •
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a. la.-
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LIQUID LIMIT (LL)
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— — HWY 392
HWY 392
Legend
.--s- (
•Approximate Boring
Locations
Site Photos SITE PLAN -
/Photos taken in approximate
location,in direction of arrow/
Boring Location Diagram
Bill Barrett Field Office
Weld County, Colorado
EEC Project #: 1132085 Date: October 2013
EARTH ENGINEERING CONSULTANTS, LLC
F"
PHOTO # 1
•
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PHOTO # 2
BILL BARRETT FIELD OFFICE
WELD COUTY,COLORADO
(.."Th
EEC PROJECT No. 1132085
NOVEMBER 2013
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING B-1 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE 10/30/2013 WHILE DRILLING 10.0'
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR N/A
SOIL DESCRIPTION 0 N 1 OU MC DD A-LIMITS I -200 SWELL
TYPE IFEETi (BLOWS.FT) (PSFI (%) (PCP) LL PI 1% PRESSURE %:d 500 PSF
SANDY LEAN CLAY(CL) 1
brown
stiff 2
with various amounts of sand _ _ °A@ 150 psi
CS 3 6 5000 14.5 106.8 31 14 46.0 200 psf 0.3%
.:,t' SS 5 6 1000 20.5
6
7
8
-9
SS 10 1 1000 32.1
BOTTOM OF BORING DEPTH 10.5' 1-1
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING B-2 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE 10/30/2013 WHILE DRILLING 10.0'
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR N/A
SOIL DESCRIPTION o N 1 OU MC DD A-LIMITS I -200 SWELL
TYPE FEET (BLOWSiFT) (PSFI (%) (PCP) LL PI 1.41 PRESSURE %:d 500 PSF
SANDY LEAN CLAY(CL)
Woven
soft to stiff 2
3 6 2000 182 102.4 55.9
•
SS 5 3 4000 16.0
-6
7
8
-9
SS 1-0 2 I 4000 I 29.8
BOTTOM OF BORING DEPTH 10.5' -11
12
13
14
15
1-6
17
1-8
1-9
2-0
2-1
2-2
2-3
2-4
2-5
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING B-3 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE 10/30/2013 WHILE DRILLING 10.0'
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR N/A
SOIL DESCRIPTION 0 N 1 OU MC DD A-uMITS I -200 SWELL
TYPE IF ETi (BLOWS.FT) (PSFI (%) (PCP) LL PI I%) PRESSURE %:d 500 PSF
SANDY LEAN CLAY(CL) 1
brown
stiff 2
%) 150 psf
CS 3 B 6000 13.9 102.9 32 16 54.8 1400 psf 2.8%
SS 5 4 4000 19.5
6
7
8
-9
SS 10 1 1000 29.2
BOTTOM OF BORING DEPTH 10.5' 1-1
12
13
14
15
16
17
18
19
20
21
22
23
24
25
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING 8-4 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE 10/30/2013 WHILE DRILLING 10.0'
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR N/A
SOIL DESCRIPTION o N 1 OU MC DD A-uMITS I -200 SWELL
TYPE FEET (BLOWSiFT) (PSFI (%) (PCP) LL PI I%) PRESSURE %:d 500 PSF
SANDY LEAN CLAY(CL) 1
dark brown/brown
soft
6 1300 26.7 95.7
•
SS 5 5 1000 20.0
-6
7
8
-9
SS 1-0 1 1000 27.4
BOTTOM OF BORING DEPTH 10.5' -11
12
13
14
15
1-6
17
1-8
1-9
2-0
2-1
2-2
2-3
2-4
2-5
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING B-5 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE I 10/30/2013 WHILE DRILLING 10.5'
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR N/A
SOIL DESCRIPTION o N 1 OU MC DD A-LIMITS -200 SWELL
TYPE IFEETI (BLOWS.FT) (PSFI (%I (PCP) LL PI 1%) PRESSURE %:d 5O0 PSF
SANDY LEAN CLAY(CL) 1
dark brown I brown _ _ .
stiff SS 2 3 4000 19.0
with calcareous deposits _ _
3
brown CS 5 4 — 31.5 93.1 31 16 64.2 <500 psf None
very soft _
6
7
8
9
SS 10 1 - 33.7
11
1-2
13
1-4
CS 15 1 - 28.3 . 98.6
1-6
17
18
SANDSTONE 1-9
brown/grey
poorly cemented SS 20 50 - 23.4
BOTTOM OF BORING DEPTH 20.5' 21
22
23
24
25
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING B-6 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE 10/30/2013 WHILE DRILLING 10.5'
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR N/A
SOIL DESCRIPTION o N 1 OU PAC DD A-LIMITS -200 SWELL
TYPE IF ETi (BLOWS.FT) (PSFI (%) (PCP) LL PI 1.41 PRESSURE %:d 5O0 PSF
TOPSOIL&VFGE-TAIICN _ _
SANDY LEAN CLAY(CL)
brown
stiff
-5 7 5000 22.6 100.8 40 21 67.2 <500 psi None
8
-9
SS 10 1 — 31.0
1-1
1-2
1-3
1-4
CS 1-5 4 — 29.7 . 92.7
1-6
17
18
SANDSTONE 1-9
brown/grey _ _
poorly cemented SS 20 48 - 23.4
BOTTOM OF BORING DEPTH 20.5' 2-1
22
23
24
25
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY,COLORADO
PROJECT NO: 1132085 LOG OF BORING B-7 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE I 10/30/2013 WHILE DRILLING 10.0'
AUGER TYPE: 4"CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV N/A 24 HOUR N/A
SOIL DESCRIPTION D N OU MC DD A-LIMITS -200 SWELL
TYPE (FEET) (BLOWS/FT) (PSF) • 4%) (PCF( LL PI ' (%) PRESSURE %@ 500 PSF
SANDY LEAN CLAY(CL) -1
brown
soft 2
less sand with depth
CS 3 6 1000 I 28.1 98.0
-4
SS -5 5 1000 21.0
-6
-7
-8
-9
SS 1-0 1 3000 29.8 92.1 39 20 86.6 <500 psf None
1-1
1-2
1-3
14
SS 15 1 — 30.1
1-6
1-7
1-8
19
SANDSTONE _ _
brown/grey/tan,poorly cemented CS 20 13 5000 28.1 100.7
2-1
2-2
2-3
24
2-5
Earth Engineering Consultants,LLC
BILL BARRETT FIELD OFFICE
WELD COUNTY, COLORADO
PROJECT NO: 1132085 LOG OF BORING B-8 DATE: NOVEMBER 2013
RIG TYPE: CME55 SHEET 1 OF 1 WATER DEPTH
FOREMAN: DG START DATE 10/30/2013 WHILE DRILLING None
AUGER TYPE: 4'CFA FINISH DATE 10/30/2013 AFTER DRILLING N/A
SPT HAMMER: AUTOMATIC SURFACE ELEV NIA 24 HOUR 8.8'
SOIL DESCRIPTION 0 N 1 Ou MC DD A-uMITS I -200 SWELL
TYPE IF ETi (6LOWS.FT) (PSFI (%) (PCP) LL PI I%) PRESSURE %:d 500 PSF
SANDY LEAN CLAY(CL) 1
brown
cliff
2 5000 19.1
5
6
7
8
-9
SS 1-0 1 1000 29.9
-11
12
13
14
SS 15 1 1000 30.2
BOTTOM OF BORING DEPTH 15.5' 1-6
17
1-8
1-9
2-0
2-1
2-2
2-3
2-4
2-5
Earth Engineering Consultants,LLC
SWELL/CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Lean Clay(CL)
Sample Location: Boring 1, Sample 1, Depth 2'
Liquid Limit: 31 Plasticity Index: 14 % Passing#200: 46.0%
Beginning Moisture: 14.5% Dry Density: 110.4 pcf Ending Moisture: 17.7%
Swell Pressure: 200 psf I%Swell @ 150: 0.3%
10.0
8.0 -
6.0 - . . . .
4.0 , .
2.0
c
E
2 0.0
c a
m
0. -2.0 WaterAdded
O
-4.0 .
m
O
v -6.0
-8.0 .
-10.0 -.
0.01 0.1 1 10
Load(TSF)
Project: Bill Barrett Field Office
Location: Weld County, Colorado EEC )
Project#: 1132085 1
Date: November 2013
SWELL/CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Lean Clay(CL)
Sample Location: Boring 3, Sample 1, Depth 2'
Liquid Limit: 32 Plasticity Index: 16 % Passing#200: 54.8%
Beginning Moisture: 13.9% Dry Density: 109.5 pcf Ending Moisture: 17.6%
Swell Pressure: 1400 psf I%Swell @ 150: 2.8%
10.0
8.0 -
6.0 - . . . . . .
4.0
2.0 __ .
V
`m Water Added
a
-2.0
O
-4.0 .
m
O
o -6.0
-8.0 .
-10.0 -.
0.01 0.1 1 10
Load(TSF)
Project: Bill Barrett Field Office
Location: Weld County, Colorado EEC
� A
Project#: 1132085 1 (v'
Date: November 2013
SWELL/CONSOLIDATION TEST RESULTS
Material Description: Dark Brown/Brown Sandy Lean Clay(CL)
Sample Location: Boring 5, Sample 2, Depth 4'
Liquid Limit: 31 Plasticity Index: 16 % Passing#200: 64.2%
Beginning Moisture: 31.5% Dry Density: 95.8 pcf Ending Moisture: 17.9%
Swell Pressure: <500 psf 1%Swell @ 500: None
10.0 -
8.0 . . . -
6.0 - •
4.0 •
2.0
c
d
d
2 0.0 •
C A
o.. 2.0 WaterAdded
O
-4.0 .
o
oo -6.0 -
U
-8.0
-10.0 •
0.01 0.1 1 10
Load(TSF)
Project: Bill Barrett Field Office
Location: Weld County, Colorado
Project#: 1132085 E E C
Date: November 2013
SWELL/CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Lean Clay(CL)
Sample Location: Boring 6, Sample 1, Depth 4'
Liquid Limit: 40 Plasticity Index: 21 % Passing#200: 67.2%
Beginning Moisture: 22.6% Dry Density: 101.4 pcf Ending Moisture: 19.1%
Swell Pressure: <500 psf I%Swell @ 500: None
10.0
8.0 - -
6.0 - — - --
m
cn
4.0 - -- -
2.0
c
0
E
c
0
a
-2.0 Water Added
0
-4.0
m
o -6.0
-8.0
-10.0 -.
0.01 0.1 1 10
Load(TSF)
Project: Bill Barrett Field Office
Location: Weld County, Colorado EEC )
Project#: 1132085 1
Date: November 2013
SWELL/CONSOLIDATION TEST RESULTS
Material Description: Brown Sandy Lean Clay(CL)
Sample Location: Boring 7, Sample 3, Depth 9'
Liquid Limit: 39 Plasticity Index: 20 % Passing#200: 86.6%
Beginning Moisture: 29.8% Dry Density: 90.1 pcf Ending Moisture: 24.5%
Swell Pressure: <500 psf 1%Swell @ 500: None
10.0 -
8.0 . .
6.0 - •
4.0 •
2.0
c
d
d
2 0.0 .
d
V
d
o. -2.0 Water Added • - . •
O
-4.0
•o
o -6.0 . . .
U
-8.0
-10.0 •
0.01 0.1 1 10
Load(TSF)
Project: Bill Barrett Field Office
Location: Weld County, Colorado
Project#: 1132085 E E C
Date: November 2013
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