The URL can be used to link to this page

Home My WebLink AboutRS_Geotech Report_SunsetWCF_200108_v1.pdf_____________________________________________________________________________________________________________________________ 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 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 tes ting RECEIVED 01/08/2020 amorganroth PLANNING DIVISION 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 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). 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. 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. 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. 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. 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. 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. 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. 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 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 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 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 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 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 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 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) - 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 90 100 0.010.1110100Percent 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 SandGravel Fines 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 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 OF 11 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 15 20 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 Tower Engineering Professionals, Inc. 326 Tryon Road Raleigh, NC 27603 Telephone: 919-661-6351 Email: geotech@tepgroup.com 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 Information Information Information Information RRRRegarding egarding egarding egarding TTTThis his his his Subsurface Exploration ReportSubsurface Exploration ReportSubsurface Exploration ReportSubsurface Exploration Report 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.