HomeMy WebLinkAboutExhibit_7_Geotech_ReportPerformed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
Date: April 30, 2019
Kasheik McGee Tower Engineering Professionals, Inc.
Crown Castle 326 Tryon Road
2055 S. Stearman Drive Raleigh, NC 27603
Chandler, AZ 85286 (919) 661-6351
Office: (602) 845-1748 Geotech@tepgroup.net
Subject: Subsurface Exploration Report - Rev 1
CCI Designation: Site Number: 831070
Site Name: A-Team
Engineering Firm Designation: TEP Project Number: 152641.247262
Site Data: 2902 NE 12th St., Renton, WA 98056 (King County)
Latitude N47° 30' 13.92'', Longitude W122° 10' 49.94''
95 Foot – Proposed Monopine Tower
Dear Kasheik McGee,
Tower Engineering Professionals, Inc. (TEP) is pleased to submit this “Subsurface Exploration Report” to
evaluate subsurface conditions in the tower area as they pertain to providing support for the tower foundation.
This report has been prepared in accordance with generally accepted geotechnical engineering practice for
specific application to this project. The conclusions in this report are based on the applicable standards of TEP’s
practice in this geographic area at the time this report was prepared. No other warranty, express or implied, is
made.
The analyses and recommendations submitted herein are based, in part, upon the data obtained from the
subsurface exploration. The soil conditions may vary from what is represented in the boring log. While some
transitions may be gradual, subsurface conditions in other areas may be quite different. Should actual site
conditions vary from those presented in this report, TEP should be provided the opportunity to amend its
recommendations as necessary.
We at Tower Engineering Professionals, Inc. appreciate the opportunity of providing our continuing professional
services to you and Crown Castle. If you have any questions or need further assistance on this or any other
projects please give us a call.
Report Prepared/Reviewed by: Jason E. Lafollette, E.I. / John D. Longest, P.E.
Respectfully submitted by:
William H. Martin, P.E.
Revision # Date Issued Description
0 April 19, 2019 Original Geotechnical report
1 April 30, 2019 Revised to include resistivity testing
RECEIVED
01/08/2020
amorganroth
PLANNING DIVISION
Exhibit 7
RECEIVED
06/03/2021
AMorganroth
PLANNING DIVISION
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 2
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
TABLE OF CONTENTS
1) PROJECT DESCRIPTION
2) PREVIOUS EXPLORATION
3) SITE EXPLORATION
4) SITE CONDITIONS AND REGIONAL GEOLOGY
5) SUBSURFACE CONDITIONS
5.1) Soil
5.2) Rock
5.3) Subsurface Water
5.4) Frost
6) TOWER FOUNDATION DESIGN
6.1) Shallow Foundation
Table 1 - Shallow Foundation Analysis Parameters
6.2) Drilled Shaft Foundation
Table 2 - Drilled Shaft Foundation Analysis Parameters
6.3) Modulus of Subgrade Reaction
7) SEISMIC
8) SOIL RESISTIVITY, pH, SULFATE, AND CHLORIDE
Table 3 - Soil Resistivity Test Results
9) CONSTRUCTION CONSIDERATIONS - SHALLOW FOUNDATION
9.1) Excavation
9.2) Foundation Evaluation/Subgrade Preparation
9.3) Fill Placement and Compaction
9.4) Reuse of Excavated Soil
10) CONSTRUCTION CONSIDERATIONS - DRILLED SHAFTS
11) SITE PHOTOGRAPHS
12) SAMPLE PHOTOGRAPHS
13) APPENDIX A
Aerial Layout
Topographic Layout
Boring Layout
14) APPENDIX B
Laboratory Testing Summary
15) APPENDIX C
Boring Log
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 3
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
1) PROJECT DESCRIPTION
Based on the preliminary drawings, it is understood a monopine communications tower will be constructed at
the referenced site. The structure loads will be provided by the tower manufacturer.
2) PREVIOUS EXPLORATION
A previous subsurface exploration was not available at the time of this report.
3) SITE EXPLORATION
The field exploration included the performance of one soil test boring (B-1) to the planned depth of 50 feet (bgs)
at the approximate location of the proposed monopine tower. The boring was performed by a track mounted drill
rig using continuous flight hollow stem augers to advance the hole. Split-spoon samples and Standard
Penetration Resistance Values (N-values) were obtained in accordance with ASTM D 1586 at a frequency of
four samples in the top 10 feet and two samples every 10 feet thereafter.
The Split-spoon samples were transported to the TEP laboratory where they were classified by a Geotechnical
Engineer in general accordance with the Unified Soil Classification System (USCS), using visual-manual
identification procedures (ASTM D 2488). Additional laboratory testing included the performance of Soil Water
Content (ASTM D 2216), and Sieve Particle-Size Gradation (ASTM D 6913) tests.
A Boring Location Plan showing the approximate boring location, a Boring Log presenting the subsurface
information obtained and a brief guide to interpreting the boring log are included in the Appendix.
4) SITE CONDITIONS AND REGIONAL GEOLOGY
The site is located at 2902 NE 12th St. in Renton, King County, Washington. The proposed tower and
compound are located in an urban area. The ground topography is lightly sloping.
The project site is located within the Puget Lowland physiographic province in Washington. Near surface
materials in this area are generally comprised of glacial-outwash from the Pleistocene Epoch. A study of area
soils from the available literature (USDA Web Soil Survey) shows that the near surface material consists of
Arents, Alderwood material (AmC). Adjacent soils near surface materials consist of Urban Land (Ur) and
Indianola Loamy Sand (InC).
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 4
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
5) SUBSURFACE CONDITIONS
The following description of subsurface conditions is brief and general. For more detailed information, the
individual Boring Log contained in Appendix C - Boring Log may be consulted.
5.1) Soil
The USCS classification of the materials encountered in the boring include SP and SM. The Standard
Penetration Resistance (“N” Values) recorded in the m aterials ranged from 4 to 42 blows per foot of
penetration.
5.2) Rock
Rock was not encountered in the boring. Refusal of auger advancement was not encountered in the
boring.
5.3) Subsurface Water
Subsurface water was not encountered in the boring at the time of drilling. It should be noted the
subsurface water level will fluctuate during the year, due to seasonal variations and construction
activity in the area.
5.4) Frost
The TIA frost depth for King County Washington is 10 inches.
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 5
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
6) TOWER FOUNDATION DESIGN
Based on the boring data, it is the opinion of TEP that a pier extending to a single large mat foundation or a
single drilled shaft can be used to support the new tower. If the drilled shaft foundation option is utilized, design
of the foundation should be adjusted to terminate in a known material. The following presents TEP’s
conclusions and recommendations regarding the foundation types.
6.1) Shallow Foundation
The foundation should bear a minimum of 10 inches below the ground surface to penetrate the frost
depth and with sufficient depth to withstand the overturning of the tower. To resist the overturning
moment, the weight of the concrete and any soil directly above the foundation can be used. TEP
recommends that the foundation designer specify a minimum unit weight for compacted backfill over
the new foundation based on what is required to resist overturning of shallow foundations. The values
are based on the current ground surface elevation and soils bearing in undisturbed native soils.
Based on preliminary site information the site is located on lightly sloping ground, with approximately
2 feet of elevation change across the planned 50 foot fenced compound area. It is recommended that
foundation designs account for site grades being raised with excavation spoils or that foundation
drawings specify minimum embedment depths based on existing site elevations and factor in ground
slopes.
Table 1 - Shallow Foundation Analysis Parameters – Boring B-1
Depth
Soil
Gross Ultimate
Bearing1
psf)
Cohesion
psf)
Friction Angle
degrees)
Total
Unit
Weight2
pcf)
Friction
Factor
Top Bottom
0 3.5 SM 5850 - 30 105 0.36
3.5 6 SM 11250 - 30 105 0.36
6 8.5 SM 19575 - 32 105 0.39
8.5 13.5 SM 21525 - 31 105 0.38
Notes:
1) The bearing values provided are gross ultimate.
2) Total unit weights provided. Effective unit weights can be achieved by subtracting unit weight of water from the total unit
weight below the subsurface water level.
3) The soil values are based on a maximum foundation size of 30 foot squared. If the foundation design size exceeds this
dimension TEP should be contacted to re-evaluate soil parameters based on the actual foundation size.
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 6
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
6.2) Drilled Shaft Foundation
The following values may be used for analysis of a drilled shaft foundation. TEP recommends the
side frictional and lateral resistance values developed in the top section of the caisson for a depth
equal to the half the diameter of the caisson or the frost depth, whichever is greater, be neglected in
the calculations. The values are based on the current ground surface elevation.
Table 2 – Drilled Shaft Foundation Analysis Parameters
Depth
Soil
Gross
Ultimate
Bearing1
psf)
Ultimate
Side Frictional
Resistance2
psf)
Cohesion
psf)
Friction Angle
degrees)
Total
Unit
Weight3
pcf) Top Bottom
0 3.5 SM 1250 70 - 30 105
3.5 6 SM 6150 200 - 30 105
6 8.5 SM 14975 330 - 32 105
8.5 13.5 SM 18175 490 - 31 105
13.5 18.5 SM 42000 800 - 34 112
18.5 23.5 SM 55700 1070 - 34 113
23.5 28.5 SP 87325 1430 - 36 113
28.5 33.5 SP 142500 1890 - 39 114
33.5 38.5 SP 182175 2280 - 40 114
38.5 43.5 SP 207700 2690 - 41 115
43.5 48.5 SP 173075 2680 - 37 113
48.5 50 SP 213075 2970 - 38 114
Notes:
1) The bearing values provided are gross ultimate. If the bearing depth of the foundation is less than 5 diameters below
the ground surface the bearing values listed in Table 1 – Shallow Foundation Analysis Parameters should be utilized.
2) The side frictional resistance values provided are ultimate.
3) Total unit weights provided. Effective unit weights can be achieved by subtracting unit weight of water from the total unit
weight below the subsurface water level.
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April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 7
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
6.3) Modulus of Subgrade Reaction
A vertical modulus of subgrade reaction and a horizontal modulus of subgrade reaction may be
derived using the following equations and soil parameters for analysis of foundations.
ks-v = 12 (SF) Qa
ks-h = ks-v B
Qa = Allowable Bearing Capacity (ksf)
SF = Factor of Safety
B = Base width (ft), use 1 if B<1ft.
ks-v = Vertical Modulus of Subgrade Reaction (kcf)
ks-h = Horizontal Modulus of Subgrade Reaction (ksf)
7) SEISMIC
The Site Class per Section 1613.3.2, of the 2015 International Building Code (2015 IBC) and Chapter 20 of
ASCE 7 (2010) based on the site soil conditions is Site Class D.
8) SOIL RESISTIVITY, pH, SULFATE, AND CHLORIDE
Soil resistivity was performed at the site utilizing a Miller 400A – 4 pin resistance meter in accordance with
ASTM G57-95a (Standard Test Method for Measurement of Soil Resistivity Using the Wenner Four-Electrode
Method). Soil resistivity testing was performed adjacent to the centerline of the proposed tower. Representative
lines showing the approximate location and orientation of the resistivity tests can be found in the Boring Layout
in Appendix A.
Table 3 – Soil Resistivity Test Results
Post
Spacing
ft)
North - South
Resistivity
ohm-cm)
East - West
Resistivity
ohm-cm)
2 180,000 91,000
4 176,000 99,000
8 148,000 127,000
16 79,000 88,000
Soil resistivity was performed at the TEP laboratory in accordance with ASTM G187-05 (Standard Test Method
for Measurement of Soil Resistivity Using the Two Electrode Soil Box Method). Test results indicated a result of
25,000 ohms-cm. The pH testing was performed at the TEP laboratory utilizing a Hanna Instruments Direct Soil
pH Meter. Test results indicated a pH of 9.28. Sulfate and chloride testing was performed at the TEP laboratory
utilizing chemical analysis. Test results indicate a sulfate content of 50 ppm and a chloride content of 25 ppm.
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 8
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
9) CONSTRUCTION CONSIDERATIONS - SHALLOW FOUNDATION
9.1) Excavation
The boring data indicates excavation to the expected subgrade level for the shallow foundation will
extend through sand. A large tracked excavator should be able to remove the materials with minimal
to moderate difficulty.
Excavations should be sloped or shored in accordance with local, state and federal regulations,
including OSHA (29 CFR Part 1926) excavation trench safety standards. It is the responsibility of the
contractor for site safety. This information is provided as a service and under no circumstance should
TEP be assumed responsible for construction site safety.
9.2) Foundation Evaluation/Subgrade Preparation
After excavation to the design elevation for the footing, the materials should be evaluated by a
Geotechnical Engineer or a representative of the Geotechnical Engineer prior to reinforcement and
concrete placement. This evaluation should include probing, shallow hand auger borings and
dynamic cone penetrometer testing (ASTM STP-399) to help verify that suitable residual material lies
directly under the foundation and to determine the need for any undercut and replacement of
unsuitable materials. Loose surficial material should be compacted in the excavation prior to
reinforcement and concrete placement to stabilize surface soil that may have become loose during the
excavation process. TEP recommends a 6-inch layer of com pacted crushed stone be placed just after
excavation to aid in surface stability.
9.3) Fill Placement and Compaction
Backfill materials placed above the shallow foundation to the design subgrade elevation should not
contain more than 5 percent by weight of organic matter, waste, debris or any otherwise deleterious
materials. To be considered for use, backfill materials should have a maximum dry density of at least
100 pounds per cubic foot as determined by standard Proctor (ASTM D 698), a Liquid Limit no greater
than 40, a Plasticity Index no greater than 20, a maximum particle size of 4 inches, and 20 percent or
less of the material having a particle size between 2 and 4 inches. Because small handheld or walk-
behind compaction equipment will most likely be used, backfill should be placed in thin horizontal lifts
not exceeding 6 inches (loose).
Fill placement should be monitored by a qualified Materials Technician working under the direction of
a Geotechnical Engineer. In addition to the visual evaluation, a sufficient amount of in-place field
density tests should be conducted to confirm the required compaction is being attained.
9.4) Reuse of Excavated Soil
The sand that meets the above referenced criteria can be utilized as backfill based on dry soil and site
conditions at the time of construction.
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 9
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
10) CONSTRUCTION CONSIDERATIONS - DRILLED SHAFTS
Based on TEP’s experience a conventional drilled shaft rig (Hughes Tool LDH or equivalent) can be used to
excavate to the termination depth of TEP’s boring. An earth auger can typically penetrate the materials
encountered to the termination depth of the boring with minimal to moderate difficulty. Materials below the auger
refusal depth may require a coring bit or roller-bit to remove the material. Special excavation equipment may be
necessary for a shaft greater that 60-inches in diameter. If hole collapse is encountered during construction, the
design and geotechnical engineers should be contacted immediately to make any necessary adjustments.
The following are general procedure recommendations in drilled shaft construction using the “dry” method:
1) Drilling equipment should have cutting teeth to result in a hole with little or no soil smeared or caked on
the sides; a spiral like corrugated side should be produced. The shaft diameter should be at least equal
to the design diameter for the full depth.
2) The drilled shaft should be drilled to satisfy a plumbness tolerance of 1.5 to 2 percent of the length and
an eccentricity tolerance of 2 to 3 inches from plan location.
3) Refer to Section 4.3 for subsurface water information. Water will fluctuate during the year and during
rain events. Any subsurface water should be removed by pumping, leaving no more than 3 inches in
the bottom of the shaft excavation.
4) A removable steel casing should be installed in the shaft for dry excavations extending beyond 15 feet
to prevent caving of the excavation sides due to soil relaxation. Loose soils in the bottom of the shaft
should be removed.
5) The drilled shaft should be evaluated by the Geotechnical Engineer or their representative to confirm
suitable end bearing conditions and to verify the proper diameter and bottom cleanliness. The shaft
should be evaluated immediately prior to and during concrete operations.
6) The drilled shaft should be concreted as soon as practical after excavation to reduce the deterioration of
the supporting soils due to caving and subsurface water intrusion.
7) The slump of the concrete is critical for the development of side shear resistance. TEP recommends a
concrete mix having a slump of 6 to 8 inches be used with the minimum compressive strength specified
by the structural engineer. A mix design incorporating super plasticizer will likely be required to obtain
this slump.
8) The concrete may be allowed to fall freely through the open area in the reinforcing steel cage provided it
is not allowed to strike the reinforcing steel or the casing prior to reaching the bottom of the shaft
excavation.
9) The protective steel casing should be extracted as concrete is placed. A head of concrete should be
maintained above the bottom of the casing to prevent soil and water intrusion into the concrete below
the casing.
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 10
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
Due to the sandy soil, the contractor may elect to utilize the “slurry” method for shaft construction. The following
are general procedure recommendations in drilled shaft construction using the “slurry” method:
1) Slurry drilled shafts are constructed by conventional caisson drill rigs excavating beneath a drilling mud
slurry. Typically, the slurry is introduced into the excavation after the groundwater table has been
penetrated and/or the soils on the sides of the excavation are observed to be caving-in. When the
design shaft depth is reached, fluid concrete is placed through a tremie pipe at the bottom of the
excavation.
2) The slurry level should be maintained at a minimum of 5 feet or one shaft diameter, whichever is
greater, above the subsurface water level.
3) Inspection during excavation should include verification of plumbness, maintenance of sufficient slurry
head, monitoring the specific gravity, pH and sand content of the drilling slurry, and monitoring any
changes in the depth of the excavation between initial approval and prior to concreting.
4) A removable steel casing may be installed in the shaft to prevent caving of the excavation sides due to
soil relaxation. Loose soils in the bottom of the shaft should be removed.
5) The specific gravity or relative density of the drilling mud slurry should be monitored from the initial
mixing to the completion of the excavation. An increase in the specific gravity or density of the drilling
slurry by as much as 10 percent is indicative of soil particles settling out of the slurry onto the bottom of
the excavation. This settling will result in a reduction of the allowable bearing capacity of the bottom of
the drilled shaft.
6) After approval, the drilled shaft should be concreted as soon as practical using a tremie pipe.
7) For slurry drilled shafts, the concrete should have a 6 to 8 inch slump prior to discharge into the tremie.
The bottom of the tremie should be set at about one tremie pipe diameter above the excavation. A
closure flap at the bottom of the tremie should be used, or a sliding plug introduced into the tremie
before the concrete, to reduce the potential for the concrete being contaminated by the slurry. The
bottom of the tremie must be maintained in concrete during placement, which should be continuous.
8) The protective steel casing should be extracted as concrete is placed. A head of concrete should be
maintained above the bottom of the casing to prevent soil and water intrusion into the concrete below
the casing.
9) Additional concrete should be placed via the tremie causing the slurry to overflow from the excavation in
order to reduce the likelihood of slurry pockets remaining in the drilled shaft.
If variability in the subsurface materials is encountered, a representative of the Geotechnical Engineer should
verify that the design parameters are valid during construction. Modification to the design values presented
above may be required in the field.
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April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 11
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
11) SITE PHOTOGRAPHS
Bentonite Backfill
Boring Location
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April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 12
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
12) SAMPLE PHOTOGRAPHS
Jar Samples
Jar Samples
Jar Samples
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April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 13
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
APPENDIX A
AERIAL LAYOUT,
TOPOGRAPHIC LAYOUT,
BORING LAYOUT
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
C-1
AERIAL LAYOUT
1
152641.247262A-TEAM
SITE #: 831070
TOWER ENGINEERING PROFESSIONALS
919) 661-6351
RALEIGH, NC 27603
326 TRYON ROAD
www.tepgroup.net
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
C-2
TOPOGRAPHIC LAYOUT
1
152641.247262A-TEAM
SITE #: 831070
TOWER ENGINEERING PROFESSIONALS
919) 661-6351
RALEIGH, NC 27603
326 TRYON ROAD
www.tepgroup.net
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
1
152641.247262A-TEAM
SITE #: 831070
TOWER ENGINEERING PROFESSIONALS
919) 661-6351
RALEIGH, NC 27603
326 TRYON ROAD
www.tepgroup.net C-3
BORING LAYOUT
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 14
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
APPENDIX B
LABORATORY TESTING SUMMARY
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
Project Name:Date:
TEP Project No.:Engineer:JDL
Boring Sample ID Depth
Moisture
Content
Liquid
Limit
Plastic
Limit
Plasticity
Index
Percent
Fines
ft][%][%]
B-1 S1 1 14.9 - - - -
B-1 S2 3.5 14.5 - - - 14.6
B-1 S3 6 15.8 - - - -
B-1 S4 8.5 16.4 - - - -
B-1 S5 13.5 8.4 - - - -
B-1 S6 18.5 17.1 - - - -
B-1 S7 23.5 9.3 - - - 2.7
B-1 S8 28.5 10.5 - - - -
B-1 S9 33.5 8.1 - - - -
B-1 S10 38.5 8.7 - - - -
B-1 S11 43.5 9.0 - - - -
B-1 S12 48.5 7.7 - - - -
326 Tryon Road, Raleigh, North Carolina 27603
Ph) 919.661.6351 (Fax) 919.661.6350
Laboratory Results Summary
Tower Engineering Professionals, Inc.
Silty sand (SM), with
sand
831070 - A-Team
152641.247262
April 18, 2019
USCS Soil
Classification
Poorly graded sand
SP)
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
Project Name:Date:
TEP Project No.:Engineer:JDL
Boring B-1
Sample S-2
Depth 3.5
Sieve
Number
Percent
Passing
3/8"87.2
4 82.5
10 78.9
20 74.6
40 65.1
60 49.7
100 33.7
140 23.0
200 14.6 *Values extrapolated linearly from measured values
Boring B-1
Sample S-7
Depth 23.5
Sieve
Number
Percent
Passing
3/8"100.0
4 100.0
10 99.8
20 99.4
40 88.1
60 44.0
100 12.3
140 5.8
200 2.7
Particle Size Analysis Results
ASTM D 6913
Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, North Carolina 27603
Ph) 919.661.6351 (Fax) 919.661.6350
831070 - A-Team April 18, 2019
152641.247262
0
10
20
30
40
50
60
70
80
90
100
0.010.1110100Percent
Passing [%]Particle Size [
mm]D60 = 0.365
mm D50 = 0.255
mm D30 = 0.134
mm D10 = 0.051
mm*Cu = 7.
1 Cc = 1.
0 SandGravel
Fines
0
10
20
30
40
50
60
70
80
90
1000.010.
1110100Percent Passing [%]Particle
Size [mm]D60 = 0.
313 mm D50 = 0.
274 mm D30 = 0.
206 mm D10 = 0.
134 mm Cu =
2.3 Cc =
1.0
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
April 30, 2019
95 Ft Monopine Subsurface Exploration Report Rev 1 A-Team 831070
Project Number 152641.247262 Page 15
Performed By: Tower Engineering Professionals, Inc.
326 Tryon Road, Raleigh, NC 27603 O) 919.661.6351 F) 919.661.6350
website: http://www.tepgroup.net
APPENDIX C
BORING LOG
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
S1
S2
S3
S4
S5
S6
S7
S8
S9
S10
S11
S12
0.0-13.5: Loose, brown, fine to coarse, silty SAND
SM), with gravel, moist
13.5-23.5: to medium dense
23.5-28.5: Medium dense, brown, fine to medium,
poorly graded SAND (SP), trace silt, moist
28.5-50.0: to dense
50.0: Boring Terminated
Calibrated Auto Hammer ETR: 97%
18
18
18
18
18
18
18
18
18
18
18
18
1-2-2
4)
2-2-2
4)
2-3-5
8)
3-3-5
8)
6-6-8
14)
8-7-8
15)
10-12-10
22)
10-13-18
31)
13-14-22
36)
15-18-24
42)
10-12-18
30)
14-18-18
36)
HOLE SIZE
140lbs / 30in
HAMMER WEIGHT/FALL
GROUND EL.
Hollow Stem Auger
LOGGED BY CHECKED BY
Renton, Washington
BACKFILL
Bentonite
LOG OF BORING B-1
PROJECT TEP NO.:
DRILLING METHOD
JDL
Auto Hammer
DATE COMPLETE
DEPTH/EL. GROUNDWATER
OF11
CITY, STATE
BORING LOCATION
HAMMER TYPE TOTAL DEPTH
831070
50.0 FT
JEL
UNIT
WEIGHTPCF4in POCKET
PENTSFSITE
ID:REMARKS SAMPLE NUMBERUNCONFINEDSTRENGTH, PSFAt the approximate location
of
the proposed tower
152641 DESCRIPTION AND
CLASSIFICATION DRILL
RIG
TYPE
B-
57
DEPTH(
FEET)
5
10
1520
25 30
35 40
45 50ELEVATION(FEET)
USCS GRAPHICSAMPLE
GRAPHICSAMPLE LENGTH(INCHES)
BLOW COUNTS(N)REC% /
RQD%DATE STARTED
A-Team 4/
15/2019 Not Encountered
4/15/2019
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
Key to Soil Symbols and Terms
TERMS DESCRIBING CONSISTENCY OR CONDITION
COARSE-GRAINED SOILS (major portions retained on No. 200 sieve): includes (1) clean
gravel and sands and (2) silty or clayey gravels and sands. Condition is rated according to
relative density as determined by laboratory tests or standard penetration resistance tests.
Descriptive Terms SPT Blow Count
Very Loose < 4
Loose 4 to 10
Medium Dense 11 to 30
Dense 31 to 50
Very Dense > 50
FINE-GRAINED SOILS (major portions passing on No. 200 sieve): includes (1) inorganic and
organic silts and clays (2) gravelly, sandy, or silty clays, and (3) clayey silts. Consistency is rated
according to shearing strength, as indicated by penetrometer readings, SPT blow count, or
unconfined compression tests.
Descriptive Terms SPT Blow Count
Very Soft < 2
Soft 2 to 4
Medium Stiff 5 to 8
Stiff 9 to 15
Very Stiff 16 to 30
Hard > 30
GENERAL NOTES
1. Classifications are bases on the Unified
Soil Classification System and include
consistency, moisture, and color. Field
descriptions have been modified to reflect
results of laboratory tests where deemed
appropriate.
2. Surface elevations are based on
topographic maps and estimated locations
and should be considered approximate.
3. Descriptions on these boring logs apply
only at the specific boring locations and at
the time the borings were made. They are
not guaranteed to be representative of
subsurface condition at other locations or
times.
Group
Symbols
GW
GP
GC
SW
SP
SC
ML
CL
OL
MH
PT
OH
CH
Well-graded gravels, gravel-sand mixtures, little or no fines
Poorly-graded gravels, little or no fines/sands
Silty gravels, gravel-sand-silt mixtures
Split Spoon
Clayey gravels, gravel-sand-silt mixtures
Well-graded sands, gravelly sands, little or no fines
Silty sands, sand-silt mixtures
Clayey sands, sand-clay mixtures
Inorganic silts and very fine sands, rock floor, silty or clayey
fine sands or clayey silts with slight plasticity
Organic silts and organic silty clays of low plasticity
Inorganic clays of high plasticity, fat clays
Organic clays of medium to high plasticity, organic silts
Peat and other highly organic soils
Poorly-graded sands, little or no fines/sands/gravels
Inorganic clays of low to medium plasticity, gravelly clays,
sandy clays, silty clays, lean clays
Inorganic silts, micaceous or distomaceous fine sandy or silty
soils, elastic silts
Pushed Shelby Tube
Auger Cuttings
Grab Sample
Dynamic Cone Penetrometer
Hand Auger
Rock Core
Typical Names Sampler Symbols
Tower Engineering Professionals, Inc.
326 Tryon Road
Raleigh, NC 27603
Telephone: 919-661-6351
Email: Geotech@tepgroup.net
GM
SM
Standard Penetration Test
SPT)
Log Abbreviations
ATD - At Time of Drilling
AD - After Drilling
EOD - End of Drilling
RMR - Rock Mass Rating
WOH - Weight of Hammer
WOR - Weight of Rod
REC - Rock Core Recovery
RQD - Rock Quality Designation
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A
InformationInformationInformationInformation RRRRegardingegardingegardingegarding TTTThishishishis
Subsurface ExplorationReportSubsurfaceExplorationReportSubsurfaceExplorationReportSubsurfaceExplorationReport
The information contained in this report has been specifically tailored to the needs of the client at the time
the report was provided, for the specific purpose of the project named in this report. The attached report
may not address the needs of contractors, civil engineers, or structural engineers. Anyone other than the
named client should consult with the geotechnical engineer prior to utilizing the information contained in
the report.
It is always recommended that the full report be read. While certain aspects of the report may seem
unnecessary or irrelevant; just as each project and site are unique, so are the subsurface investigation
reports and the information contained in them. Several factors can influence the contents of these reports,
and the geotechnical engineer has taken into consideration the specific project, the project location, the
client’s objectives, potential future improvements, etc. If there is any question about whether the attached
report pertains to your specific project or if you would like to verify that certain factors were considered in
the preparation of this report, it is recommended that you contact the geotechnical engineer.
Geotechnical subsurface investigations often are prepared during the preliminary stages of a project and
aspects of the project may change later on. Some changes may require a report revision or additional
exploration. Some changes that often need to be brought to the attention of the geotechnical engineer
include changes in location, size and/or type of structure, modifications to existing structures, grading
around the project site, etc. Some naturally occurring changes can also develop that impact the information
contained in this geotechnical report such as earthquakes, landslides, floods, subsurface water levels
changing, etc. It is always recommended that the geotechnical be informed of known changes at the
project site.
Subsurface exploration reports are generated based on the analysis and professional opinions of a
geotechnical engineer based on the results of field and laboratory data. Often subsurface conditions can
vary – sometimes significantly – across a site and over short distances. It often is helpful to retain the
geotechnical engineer’s services during the construction process. Otherwise, the geotechnical cannot
assume responsibility or liability for report recommendations which may have needed to change based on
changing site conditions or misinterpretation of recommendations.
Geotechnical engineers assemble testing and/or boring logs based on their interpretation of field and
laboratory data. Testing and/or boring logs should always be coupled with the subsurface exploration
report. The geotechnical engineer and Tower Engineering Professionals cannot be held reliable for
interpretations, analyses, or recommendations based solely on the testing and/or boring log if it is
independent of the prepared report.
The scope of the subsurface exploration report does not include an assessment or
analysis of environmental conditions, determination of the presence or absence of
wetlands or hazardous or toxic materials on or below the ground surface. Any notes
regarding odors, fill, debris, or anything of that nature are offered as general
information for the client, often to help identify or delineate natural soil boundaries.
For additional information, please contact the geotechnical engineer named in the
attached report.
DocuSign Envelope ID: 10F04B11-B1B6-4ECF-85A1-13D99F6F674A