GEOTECHNICAL ENGINEERING REPORT BELVILLE RIVERWALK BELVILLE, NORTH CAROLINA S&ME Project No Prepared For:

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1 GEOTECHNICAL ENGINEERING REPORT BELVILLE RIVERWALK BELVILLE, NORTH CAROLINA S&ME Project No Prepared For: Town of Belville 497 Olde Waterford Way, Suite 205 Belville, NC Prepared By: 3006 Hall Waters Drive, Suite 100 Wilmington, NC NC PE Firm License No. F-0176 April 17, 2015

2 April 17, 2015 Town of Belville 497 Olde Waterford Way, Suite 205 Belville, NC Attention: Reference: Ms. Athina D. Williams Proposal for Geotechnical Services Proposed Belville Riverwalk Belville, North Carolina S&ME Project No Dear Mr. Williams: We are pleased to present this Geotechnical Engineering Report for the above-referenced project. Our services were provided in general accordance with S&ME Proposal No dated February 17, This report presents the findings of our subsurface exploration along with geotechnical design and construction recommendations based on these findings. The recommendations given in this report should be incorporated into the design drawings, specifications, and contract documents for this project. S&ME appreciates having the opportunity to be of service to you during this phase of the project. If you have any questions or comments after reviewing this report, please let us know so we can address them. Sincerely, S&ME, Inc. Jonathan P. Gerdes, EI Staff Professional Tom Schipporeit, PE, M.ASCE Senior Geotechnical Engineer Copies to: Mr. Jeff Cappadona, Cavanaugh S&ME, INC. / 3006 Hall Waters Drive, Suite 100 / Wilmington, NC / p /

3 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, 2015 TABLE OF CONTENTS 1 PROJECT INFORMATION INFORMATION SOURCES SITE DESCRIPTION PROJECT DESCRIPTION ASSUMPTIONS FIELD EXPLORATION PROGRAM HAND AUGER BORINGS CONE PENETROMETER TEST SOUNDINGS SOIL TEST BORINGS LABORATORY TESTING SUBSURFACE CONDITIONS AREA GEOLOGY SOIL SURVEY HAND AUGER BORINGS BORINGS & CPT SOUNDINGS CONCLUSIONS AND RECOMMENDATIONS SEISMIC DESIGN...6 General...6 Seismic Site Class...6 Liquefaction Evaluation...6 Liquefaction Mitigation...7 Ground Motion Parameters FOUNDATION SUPPORT LIMITATIONS OF GEOTECHNICAL REPORT...10 APPENDIX Important Information about Your Geotechnical Engineering Report Figure 2 Field Test Location Plan Figure 3 Soils Map Hand Auger Boring Logs Field Testing Procedures for CPT Soundings CPT Soil Classification Legend Cone Penetrometer Test (CPT) Logs Field Testing Procedures for Soil Test Borings Legend to Soil Classification and Symbols Boring Logs Laboratory Test Results i

4 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, PROJECT INFORMATION 1.1 Information Sources This report is based on the following sources of information: Mr. Jeff Cappadona, P.E. of Cavanaugh Associates, P.A Ms. Athina Williams with the Town of Belville Preliminary Conceptual Riverwalk Plan drawings prepared by Commissioner Joe Breault for the Town of Belville dated January 28, Site visit by Jonathan Gerdes of S&ME on February 11, Information obtained from the Google Earth website. S&ME s past experience with similar projects and general subsurface conditions in the project site area. 1.2 Site Description The site is located east of Highway 133 in Belville, North Carolina, at the approximate location shown on Figure 1. It currently includes an asphalt-paved parking lot with boat ramp access into the Brunswick River. The adjacent portion of the site north of the parking lot is heavily wooded and bounded by the Brunswick River marsh land and Highway 133. Previously cleared paths have been cut through the wooded area of the site where construction on a structure has started. Figure 1 Site Location 1

5 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, Project Description We understand that the Town of Belville has proposed a conceptual plan for a riverwalk along the Brunswick River. The project is to include 2,353 feet of pedestrian trails, 113 feet of 6- feet-wide raised wooden pedestrian walkways, and 692 feet of 10 feet-wide raised wooden pedestrian walkways. The raised wooden walkways will cross marsh areas. Two new piers and observation decks will extend out into the river. 1.4 Assumptions We assume that: The raised pedestrian walkways and piers will be wood framed structures supported on timber piles Service (i.e., unfactored) design foundation loads for the proposed elevated walkways and piers will be relatively light and will require pile compression design capacities on the order of 5 to 10 kips per pile. Site retaining walls will not be required to achieve design grades. The soil and groundwater at the subject site are not contaminated, and the proposed geotechnical explorations will not require environmental protocols (e.g., drumming of drilling fluid and cuttings, steam cleaning of drilling tools between borings, grouting of boreholes, monitoring of volatile organics, etc). We have made these assumptions based on the project information provided to us and our experience with similar projects. The conclusions and recommendations given in this report are based on the background information provided to us and on our assumptions. 2 FIELD EXPLORATION PROGRAM 2.1 Hand Auger Borings Our field exploration included advancing two hand auger borings (designated HA-1, and HA- 2), to a depth of 3.0 and 2.0 feet, respectfully, below the existing ground surface. The encountered soils were visually-manually classified in the field in general accordance with the Unified Soil Classification System. Hand auger boring logs are attached. The hand auger borings were advanced approximately 10 feet into the marsh from the edge of the upland areas next to the marsh. The hand auger boring locations are shown on Figure 2 in the Appendix. Since the borings were located in the field by our personnel by estimating right angles, and approximating distances using existing site features, their locations should be considered approximate. 2.2 Cone Penetrometer Test Soundings S&ME s subcontract driller advanced four cone penetration test (CPT) soundings on April 5, 2015, in general accordance with the attached Field Testing Procedures. The approximate 2

6 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, 2015 sounding locations are shown on Figure 2. Since the soundings were located in the field by using a hand-held GPS unit, estimating right angles, and approximating distances using existing site features, their locations should be considered approximate. The soundings were advanced at the edge of the upland areas adjacent to the marsh, as the drill rig could not access the proposed elevated walkway locations out in the marsh. The soundings were advanced to depths ranging from 13.1 to 38.5 feet beneath the existing ground surface. Soundings S-02and S-03 were planned for depths of 30 feet, but refusal to CPT equipment advancement was encountered at depths of 13.1, 17.1 and 20.2 feet, respectively. Due to the shallow refusal, the CPT rig was offset and an additional sounding designated S-02A was advanced near S-02. It also encountered shallow refusal. CPT sounding logs showing the soils encountered (based on soil behavior type) are attached. 2.3 Soil Test Borings S&ME s subcontract driller advanced four soil test borings (B-01 through B-04) in the Brunswick River to depths of 38 to 43 feet below the river s mud line on March 31 and April 1, 2015 in general accordance with the attached Field Testing Procedures. The depth of the river was measured in all locations at time of drilling to be approximately three feet deep. Representative portions of the split-spoon samples were returned to our laboratory for visualmanual classification in general accordance with the Unified Soil Classification System. Boring logs containing soil descriptions, SPT N-values, and drilling observations are included with this report. The approximate boring locations are shown in Figure 2 in the Appendix. Since the borings were located in the field by our personnel by using a hand-held GPS, estimating right angles, and approximating distances using existing site features, their locations should be considered approximate. 3 LABORATORY TESTING S&ME performed moisture content tests, grain-size tests, Atterberg limits, and organic content tests on representative samples obtained from the borings. These tests were performed to confirm visual soil classifications and estimate the engineering properties of the soils tested. Testing was performed in general accordance with applicable ASTM standards. The test results are attached in the Appendix. 4 SUBSURFACE CONDITIONS 4.1 Area Geology The site is located within the Coastal Plain Physiographic Province of North Carolina. The Coastal Plain Province is typically characterized by marine, alluvial, and aeolian sediments that were deposited during periods of fluctuating sea levels and moving shorelines. The soils and basal formations in the North Carolina Coastal Plain Physiographic Province are typical of those 3

7 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, 2015 laid down in a shallow sloping sea bottom; interbedded sands and clays with irregular deposits of shells and layers of limestone and cemented sands. Alluvial sands, silts, and clays are typically present near rivers and creeks. Deposits of peat, organic silt, and organic clay are also typically present in or near current or former tidal marsh areas in the outer portion of the Coastal Plain. According to the 1985 Geologic Map of North Carolina, the site is underlain by the Peedee Formation. This Cretaceous formation consists of greenish gray to olive black, massive, glauconitic sand, clayey sand, and clay which is locally fossiliferous and calcareous. Patches of sandy muscollan-mold limestone can be present in the upper part of this formation. The coastal formations on the geologic map are typically on the order of 30 to 80 feet feet below the ground surface. They represent basal, relatively hard formations with consistency over large areas. 4.2 Soil Survey A map of the near-surface soils is given in Figure 3. The Soil Survey Report for Brunswick County, North Carolina, (published by the United States Department of Agriculture Soil Conservation Service in 1982) indicates that the project site is underlain primarily by the soil series listed in the following table. The following soil properties and characteristics are given in the Soil Survey Report for these soils: Table 1 Soil Survey Soil Properties Soil Name BaB - Baymeade BnB Blanton BDC Baymeade & Marvyn Lo Leon* CH Chowan MaC Marvyn Typical Depth (in) Unified Classification SM, SP-SM SC, SM, SM-SC SM, SP-SM SP-SM SM % Passing No. 200 Sieve Liquid Limit -- < < 25 Plasticity Index NP NP 10 NP NP NP 3 See Baymeade and Marvin. Soils are combined because of similarities in use and management. High Water Table (ft) Apparent Dec-Apr Perched Dec - Mar 0-80 SP, SP-SM* NP Apparent Jun-Feb CL-ML, ML, MH CL, ML, MH PT SM ML, SC, SM-SC, SM ML, MH, SM SM, SC, ML, CL < NP NP NP Apparent Nov - Apr > 6.0 4

8 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, Hand Auger Borings The hand auger borings encountered 1.5 to 2.5 feet of peat (PT) overlying poorly graded sand (SP). Groundwater was encountered at the ground surface in both hand auger borings. The soils were visually-manually classified as saturated. Groundwater levels have been measured or inferred in the explorations at the times and under the conditions stated on the logs in this report. Changes in the groundwater conditions and depths may occur due to seasonal variations in rainfall, evaporation, construction activity, surface water runoff, tides, and other site specific factors. 4.4 Borings & CPT Soundings Borings B-01, B-02, B-03, and B-04 encountered approximately of 3 feet of water above the mud line of the Brunswick River. Alluvial sediments were encountered to depths ranging from 33 to 38 feet below the mud line. On average, the alluvial sediments consisted of 30 feet of very soft to soft clay (CL, CH), organic soils (PT, OH) and loose clayey sand (SC) overlying approximately 10 feet of loose to dense sands (SP, SP-SM, SM, SC). The alluvial sediments are underlain by limestone sampled as dense to very dense clayey sand (SC) with cemented fragments, which is interpreted as the Peedee Formation. Please note that Boring B-04 encountered wood fragments between depths of 20 and 21 feet, below water level. The CPT soundings encountered three basic soil strata within the maximum exploration termination depth of 38.5 feet. The strata interpreted from the CPT soundings represent approximate boundaries between soil behavior types 1. Based on our experience, the soil behavior type listed as gravelly sand on the CPT logs most likely classifies as a silty sand (SM) or clayey sand (SC). The strata are interpreted as approximately 14 feet of very loose to loose sands (SM, SC, SP-SM) overlying 3 feet of very soft clays (CH, CL) overlying 10 feet medium dense to dense sands (SM, SC, SP, SP-SM). In sounding S-01 an isolated zone of medium dense sand was encountered between 3 and 7 feet below ground surface. Groundwater levels were measured in the holes made by the CPT soundings. The groundwater levels varied from depths of approximately 1 to 2 feet below the existing ground surface. Groundwater levels have been measured or inferred in the explorations at the times and under the conditions stated on the logs in this report. Changes in the groundwater conditions and depths may occur due to seasonal variations in rainfall, evaporation, construction activity, surface water runoff, and other site specific factors. 1 Soil Behavior Type is calculated based on empirical correlations which use the three fundamental penetrometer measurements (i.e., tip resistance, sleeve friction, and pore pressure). A CPT may define a soil based on its behavior as one type, while its grain size and plasticity (the traditional basis for soil classification) may define it as a different type. 5

9 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, CONCLUSIONS AND RECOMMENDATIONS 5.1 Seismic Design General There are no known, mapped faults in the Wilmington area. Five minor earthquakes with epicenters in the Wilmington area with magnitudes of 3.0 to 3.9 occurred in between 1871 and The historic earthquake event which influences the design seismicity of the Wilmington area the most is the 1886 Charleston, South Carolina, earthquake with a magnitude of 7.3. Seismic Site Class Per Section 1613 of the 2012 North Carolina Building Code, a Seismic Site Class E is recommended for design, based on the Standard Penetration Test N-values measured in the soil test borings and more than 10 feet of soil within the upper 100 feet of the subsurface profile having the following characteristics: 1. Plasticity Index PI > Moisture Content w > 40%;, and 3. Undrained Shear Strength Su<500 psf. Liquefaction Evaluation Because of the presence of isolated zones of loose sands below the water table at the site, we performed a seismic liquefaction analysis based on the design earthquake (M=7.25). The design earthquake has a 2 percent probability of exceedance in a 50 year period. This is equivalent to an earthquake that has the likelihood of occurring once every 2,475 years. Using the 2012 North Carolina Building Code (which is based on the 2009 International Building Code), the design seismic event has a peak ground acceleration (pga) of 0.188g at this site. This value was calculated using Seismic Site Class E, calculating the five-percent damped spectral response acceleration at short periods, SDS, using the USGS website tool for U.S. Seismic Design Maps, and dividing SDS by 2.5 per Section (2) of the 2012 North Carolina Building Code. Liquefaction can create potential problems such as: ground surface disruption (i.e. sand boils), volumetric compression (i.e. settlement), and decrease in pile capacity due to loss of skin friction with the surrounding sand. When soils susceptible to liquefaction are located within approximately 10 feet of the surface, ground surface disruptions are likely. 2 Map of Earthquake Epicenters in North Carolina and Portions of Adjacent States ( ), North Carolina Geologic Survey. 6

10 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, 2015 For this site, our analyses indicate that there is a moderate risk of liquefaction with some surface manifestation possible 3 (based on 5 < Liquefaction Potential Index 4 < 15.) Our analyses indicate that the liquefiable soils at this site are present within 10 feet of the existing ground surface, indicating the potential for surface disruption, and a depths below 10 feet. We estimate liquefaction-induced ground surface settlement of 2 to 11inches due to the design earthquake, using the Ishiari and Yoshimine method. Liquefaction Mitigation Due to the moderate risk for liquefaction to occur under the design earthquake, in addition to the required elevations and poor foundation soils, we recommend that the proposed elevated walkways and piers be supported on piles, as discussed in Section 5.2. The pile capacities given take into account the negligible shear strength of liquefied sands during the design earthquake. Ground Motion Parameters We recommend that the project be designed using the ground motion parameters given in the following table: Table 2 Ground Motion Parameters NC Bldg. Code Site Class Ss S1 F a Fv S DS S D E g g g g Using the spectral accelerations presented in Table 1 and an Occupancy Category I, II, and III (assumed), the Seismic Design Category is D. 5.2 Foundation Support We recommend that driven timber piles be used for support of the proposed elevated walkways and pier structures. Estimated pile tip elevations and geotechnical design capacities (in kips) are given in the following table. We assume that the piers will be supported by round tapered timber piles, and that the elevated walkways will be supported by either round tapered timber piles or square timber piles. 3 Toprak, S., and Holzer, T. L. (2003). Liquefaction potential index: Field assessment. J. Geotech. Geoenviron. Eng., 129 (4), Iwasaki, T., Tokida, K., Tatsuoka, F., Watanabe, S., Yasuda, S., and Sato, H. (1982). Microzonation for soil liquefaction potential using simplified methods. Proc., 3rd Int. Earthquake Microzonation Conf., US National Science Foundation, Washington, DC.,

11 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, 2015 Table 3 Timber Pile Recommendations Proposed Structure Elevated Marsh Walkway Pier & Observation Site 2 Pier & Observation Site 1 Borings Estimated Tip Elevations (feet) S S-02, S- 02A -9 S B-01, B to -32 B-03, B to -41 Pile Type Round Tapered Timber Square Timber Round Tapered Timber Square Timber Round Tapered Timber Square Timber Round Tapered Timber Round Tapered Timber Pile Size 8 in. minimum tip diameter 8 in. minimum sides 8 in. minimum tip diameter 8 in. minimum sides 8 in. minimum tip diameter 8 in. minimum sides 8 in. minimum tip diameter 8 in. minimum tip diameter Geotechnical Allowable Load (kips) Axial (Vertical) Compression (download) Tension (uplift) A factor of safety was applied to the estimated ultimate loads to estimate the allowable design loads. A factor of safety of 2.0 was used for compression loads and a factor of safety of 3.0 was used for tension loads. The shear strength of potentially liquefiable sands was ignored in estimating the skin friction and allowable pile capacities. The ability of the pile sections to structurally resist these loads should be evaluated by the project structural engineer. Timber piles should be treated Southern Yellow Pine and meet the requirements of ASTM D 25 for timber end bearing piles. The piles should be clean peeled and CCA pressure treated in accordance with the requirements of AWPA C3. We recommend that piles be spaced on-center no closer than the three times the pile diameter or width; a center-to-center spacing of approximately 3 feet. The minimum spacing should be maintained to prevent the pile group compression load capacity from being significantly less than the summation of individual pile capacities. This spacing restriction also serves to limit surface heave and to reduce the possibility of damaging previously installed piles. 8

12 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, 2015 A series of indicator piles should be installed prior to ordering production piles. The indicator piles should be 10 feet longer than the anticipated production pile lengths. Indicator pile installation should be observed by the geotechnical engineer. The results of the indicator pile driving can be used to evaluate driving resistance, termination criteria, pile length, and required predrilling depths, if necessary. The indicator piles are expected to be part of the design pile layout. We recommend that the pile hammer with a rated energy of at least 5,000 foot-pounds per blow be used to install the piles. An impact hammer (air, hydraulic, or diesel) should be used to install the piles and verify that the design compression capacity is achieved. Compression capacity cannot be verified if a vibratory hammer is used. All equipment should be subject to the review of the geotechnical engineer. The same pile driving rig and hammer should be used to drive indicator and production piles. Please note that driving piles at the subject site will generate noise which can be a nuisance to nearby building occupants and property owners. Ground vibrations could be transmitted to nearby structures, but are typically well below structural vibration thresholds for timber piles driven at least 50 feet horizontally from existing structures. Sounding S-01 encountered medium dense sand in the upper 10 feet, and logs, stumps, and other debris are potentially present in the marsh. Therefore, predrilling or preaugering at least to a depth of 10 feet at each pile location for the elevated walkways in the marsh is recommended. The augers used for predrilling should have a diameter equal to or slightly smaller than the tip dimension of the pile. We do not anticipate a need for general tip protection of the piles if predrilling is performed. The geotechnical engineer should be retained to perform continuous Special Inspections of driven timber piles (per Chapter 17 of the 2012 North Carolina Building Code). The geotechnical engineer s representative should: Verify element materials, sizes and lengths comply with project requirements Determine capacities of indicator piles Observe driving operations and maintain complete and accurate records for each pile Verify placement locations and general plumbness Confirm type and size hammer used Record number of blows per foot of penetration Record tip and top elevations Document any damage to piles observed during driving 9

13 Geotechnical Engineering Report S&ME Project No Belville Riverwalk, Belville, NC April 17, LIMITATIONS OF GEOTECHNICAL REPORT This report has been prepared in accordance with generally accepted geotechnical engineering practice for specific application to this project. Any wetland, environmental, or contaminant assessment efforts are beyond the scope of this geotechnical exploration; and therefore, those issues are not addressed in this report. The conclusions and recommendations contained in this report are based upon applicable standards of our practice in this geographic area at the time this report was prepared. No other warranty, expressed or implied, is made. Conclusions and recommendations submitted in this report are based, in part, upon the data obtained from the geotechnical exploration. The nature and extent of variations between and away from the borings, soundings, and/or test pits may not become evident until construction. If variations appear evident, then it will be necessary to re-evaluate the recommendations of this report. In the event that any changes in the grades, nature, design, or location of the proposed project are planned, the recommendations contained in this report should be reviewed and modified or confirmed in writing. A document prepared by S&ME and titled Important Information About Your Geotechnical Engineering Report is provided in the Appendix. This document discusses how geotechnical recommendations are developed based on professional opinions of site subsurface conditions, limited exploration information, and experience. Variations in subsurface conditions can be a principal cause of construction delays, cost overruns, and claims. This document is provided to assist you and other members of the project team in understanding and managing the risk of these variations. S&ME should be provided the opportunity to review the final plans and specifications in order that earthwork, foundation, and other recommendations are properly interpreted and implemented. The recommendations in this report are contingent on S&ME s observation and monitoring of geotechnical construction activities. 10

14 APPENDIX S&ME, INC. / 3006 Hall Waters Drive, Suite 100 / Wilmington, NC / p /

15 Important Information About Your Geotechnical Engineering Report Variations in subsurface conditions can be a principal cause of construction delays, cost overruns and claims. The following information is provided to assist you in understanding and managing the risk of these variations. Geotechnical Findings Are Professional Opinions Geotechnical engineers cannot specify material properties as other design engineers do. Geotechnical material properties have a far broader range on a given site than any manufactured construction material, and some geotechnical material properties may change over time because of exposure to air and water, or human activity. Site exploration identifies subsurface conditions at the time of exploration and only at the points where subsurface tests are performed or samples obtained. Geotechnical engineers review field and laboratory data and then apply their judgment to render professional opinions about site subsurface conditions. Their recommendations rely upon these professional opinions. Variations in the vertical and lateral extent of subsurface materials may be encountered during construction that significantly impact construction schedules, methods and material volumes. While higher levels of subsurface exploration can mitigate the risk of encountering unanticipated subsurface conditions, no level of subsurface exploration can eliminate this risk. Scope of Geotechnical Services Professional geotechnical engineering judgment is required to develop a geotechnical exploration scope to obtain information necessary to support design and construction. A number of unique project factors are considered in developing the scope of geotechnical services, such as the exploration objective; the location, type, size and weight of the proposed structure; proposed site grades and improvements; the construction schedule and sequence; and the site geology. Geotechnical engineers apply their experience with construction methods, subsurface conditions and exploration methods to develop the exploration scope. The scope of each exploration is unique based on available project and site information. Incomplete project information or constraints on the scope of exploration increases the risk of variations in subsurface conditions not being identified and addressed in the geotechnical report. Services Are Performed for Specific Projects Because the scope of each geotechnical exploration is unique, each geotechnical report is unique. Subsurface conditions are explored and recommendations are made for a specific project. Subsurface information and recommendations may not be adequate for other uses. Changes in a proposed structure location, foundation loads, grades, schedule, etc. may require additional geotechnical exploration, analyses, and consultation. The geotechnical engineer should be consulted to determine if additional services are required in response to changes in proposed construction, location, loads, grades, schedule, etc. Geo-Environmental Issues The equipment, techniques, and personnel used to perform a geo-environmental study differ significantly from those used for a geotechnical exploration. Indications of environmental contamination may be encountered incidental to performance of a geotechnical exploration but go unrecognized. Determination of the presence, type or extent of environmental contamination is beyond the scope of a geotechnical exploration. Geotechnical Recommendations Are Not Final Recommendations are developed based on the geotechnical engineer s understanding of the proposed construction and professional opinion of site subsurface conditions. Observations and tests must be performed during construction to confirm subsurface conditions exposed by construction excavations are consistent with those assumed in development of recommendations. It is advisable to retain the geotechnical engineer that performed the exploration and developed the geotechnical recommendations to conduct tests and observations during construction. This may reduce the risk that variations in subsurface conditions will not be addressed as recommended in the geotechnical report. Portion obtained with permission from Important Information About Your Geotechnical Engineering Report, ASFE, 2004 S&ME, Inc. 2010

16 LEGEND S&ME Hand Auger Borings Advanced 3/25/2015 S&ME Soil Test Borings Drilled 3/31/15 and 4/1/15 S&ME CPT Soundings Advanced 4/5/2015 S-01 HA-1 S-02, 2A HA-2 B-02 B-01 S-03 B-03 B-04 REFERENCE: Preliminary Conceptual Riverwalk Plan drawings prepared by Commissioner Joe Breault for the Town of Belville dated 1/28/2015 SCALE: NOT TO SCALE CHECKED BY: JPG DRAWN BY: TMS DATE: 4/10/2015 FIELD TEST LOCATION PLAN BELVILLE RIVERWALK BELVILLE, NORTH CAROLINA S&ME PROJECT NUMBER: FIGURE NUMBER

17 SCALE: NOT TO SCALE CHECKED BY: JPG DRAWN BY: TMS DATE: 4/10/2015 SOILS MAP BELVILLE RIVERWALK BELVILLE, NORTH CAROLINA S&ME PROJECT NUMBER: FIGURE NUMBER

18 Form No. TR-HAPT-01 Revision No. : 0 HAND AUGER & PENETROMETER TESTING BORING LOGS Revision Date: 6/11/10 S&ME, Inc. - Wilmington 3006 Hall Waters Drive, Suite 100, Wilmington, NC Project No.: Project Name: Belville Riverwalk Report Date: 3/25/2015 Client: Address: Test Date(s): 3/25/2015 Project Location: Belville, NC Field Personnel: Jonathan Gerdes Hammer Weight: 15-Lbs. Stratification Hammer Blows ** Test Location Depth* Soil Description Depth* Increment feet feet 1st 2nd 3rd HA ' Saturated Black Brown PEAT (PT) Marsh 2.5' - 3' Saturated Dark Gray Poorly Graded SAND (SP) Average HA ' 1.5-2' Boring terminated at 3 feet Groundwater encountered at surface. Saturated Black Brown PEAT (PT) Marsh Saturated Dark Gray Brown Poorly Graded SAND (SP) Boring terminated at 2 feet Groundwater encountered atsurface. References / Comments / Deviations: * Depth is Referenced from existing subgrade ** Number of hammer blows required to drive cone point 1 3/4 inches per increment using a 15-Lb. weight falling 20 inches. Technical Signature Responsibility Date Position This report shall not be reproduced, except in full without the written approval of S&ME, Inc HADCP Logs.xlsx Page 1 of 1

19 FIELD TESTING PROCEDURES Cone Penetrometer Test (CPT) Sounding The cone penetrometer test soundings (ASTM D 5778) were performed by hydraulically pushing an electronically instrumented cone penetrometer through the soil at a constant rate. As the cone penetrometer tip was advanced through the soil, nearly continuous readings of point stress, sleeve friction and pore water pressure were recorded and stored in the on-site computers. Using theoretical and empirical relationships, CPT data can be used to determine soil stratigraphy and estimate soil properties and parameters such as effective stress, friction angle, Young s Modulus and undrained shear strength. The consistency and relative density designations, which are based on the cone tip resistance, q t for sands and cohesive soils (silts and clays) are as follows: SANDS Cone Tip Resistance, q t (tsf) Relative Density SILTS AND CLAYS Cone Tip Resistance, q t (tsf) Consistency <20 Very Loose <5 Very Soft Loose 5 10 Soft Medium Dense Firm Stiff Dense Very Stiff >200 Very Dense >60 Hard CPT Correlations References are in parenthesis next to the appropriate equation. General p a = atmospheric pressure (for unit normalization) q t = corrected cone tip resistance (tsf) f s = friction sleeve resistance (tsf) R f = 100% * (f s /q t ) u 2 = pore pressure behind cone tip (tsf) u 0 = hydrostatic pressure B q = (u 2 -u 0 )/(q t -σ v0 ) Q t = (q t -σ v0 )/ σ v0 F r = 100% * f s /(q t - σ v0 ) I c = ((3.47-logQ t ) 2 +(logf r +1.22) 2 ) 0.5 N-Value N 60 = (q t /pa)/[8.5(1-i c /4.6)] (6) (6) Jefferies, M.G. and Davies, M.P., (1993), Use of CPTu to estimate equivalent SPT N60, ASTM Geotechnical Testing Journal, Vol. 16, No. 4

20 CPT Soil Classification Legend Robertson's Soil Behavior Type (SBT), 1990 Group # Description Ic Min Max 1 Sensitive, fine grained N/A 2 Organic soils - peats 3.60 N/A 3 Clays - silty clay to clay Silt mixtures - clayey silt to silty clay Sand mixtures - silty sand to sandy silt Sands - clean sand to silty sand Gravelly sand to dense sand N/A Very stiff sand to clayey sand (High OCR or cemented) N/A 9 Very stiff, fine grained (High OCR or cemented) N/A Soil behavior type is based on empirical data and may not be representative of soil classification based on plasticity and grain size distribution. Relative Density and Consistency Table SANDS SILTS and CLAYS Cone Tip Stress, qt (tsf) Relative Density Cone Tip Stress, qt (tsf) Consistency Less than 20 Very Loose Less than 5 Very Soft Loose 5-15 Soft to Firm Medium Dense Stiff Dense Very Stiff Greater than 200 Very Dense Greater than 60 Hard

21 Date: Estimated Water Depth: Rig/Operator: Apr. 5, ft GRB Belville Riverwalk Belville, NC S&ME Project No: Cone Penetration Test S-01 Total Depth: Termination Criteria: Cone Size: 38.5 ft Target Depth Depth (ft) 0 Tip Resistance q t (tsf) Sleeve Friction Pore Pressure f s (tsf) u 2 (tsf) u Friction Ratio R f (%) Equivalent N SBT Bq MAI = 4 Elev (ft) 5 5 Gravelly Sand to Sand 0 10 Sand Mixtures-Silty Sand to Sandy Silt Sand Mixtures-Silty Sand to Sandy Silt -5 CPT REPORT - STANDARD - SBT BQ CPT.GPJ LIBRARY 2011_06_28.GDT 4/10/ Page 1 of 2 Electronic Filename: b=1.cpt Sand Mixtures-Silty Sand to Sandy Silt Clays-Clay to Silty Clay Clays-Clay to Silty Clay Sands-Clean Sand to Silty Sand Gravelly Sand to Sand Sands-Clean Sand to Silty Sand S-01

22 Date: Estimated Water Depth: Rig/Operator: Apr. 5, ft GRB Belville Riverwalk Belville, NC S&ME Project No: Cone Penetration Test S-01 Total Depth: Termination Criteria: Cone Size: 38.5 ft Target Depth Depth (ft) 35 Tip Resistance q t (tsf) Sleeve Friction Pore Pressure f s (tsf) u 2 (tsf) u Friction Ratio R f (%) Equivalent N SBT Bq MAI = 4 Elev (ft) -30 Sands-Clean Sand to Silty Sand CPT REPORT - STANDARD - SBT BQ CPT.GPJ LIBRARY 2011_06_28.GDT 4/10/15 Page 2 of 2 Electronic Filename: b=1.cpt S-01

23 Date: Estimated Water Depth: Rig/Operator: Apr. 5, ft GRB Belville Riverwalk Belville, NC S&ME Project No: Cone Penetration Test S-02 Total Depth: Termination Criteria: Cone Size: 13.1 ft Maximum Reaction Force Depth (ft) 0 Tip Resistance q t (tsf) Sleeve Friction Pore Pressure f s (tsf) u 2 (tsf) u Friction Ratio R f (%) Equivalent N SBT Bq MAI = 4 Elev (ft) 5 Sands-Clean Sand to Silty Sand 0 CPT REPORT - STANDARD - SBT BQ CPT.GPJ LIBRARY 2011_06_28.GDT 4/10/15 10 Page 1 of 1 Electronic Filename: b-2.cpt Sand Mixtures-Silty Sand to Sandy Silt Sands-Clean Sand to Silty Sand Sands-Clean Sand to Silty Sand -5 S-02

24 Date: Estimated Water Depth: Rig/Operator: Apr. 5, ft GRB Belville Riverwalk Belville, NC S&ME Project No: Cone Penetration Test Total Depth: Termination Criteria: Cone Size: S-02A 17.1 ft Maximum Reaction Force Depth (ft) 0 Tip Resistance q t (tsf) Sleeve Friction Pore Pressure f s (tsf) u 2 (tsf) u Friction Ratio R f (%) Equivalent N SBT Bq MAI = 4 Gravelly Sand to Sand Elev (ft) 5 Sands-Clean Sand to Silty Sand Sand Mixtures-Silty Sand to Sandy Silt 0 10 Sands-Clean Sand to Silty Sand -5 Sand Mixtures-Silty Sand to Sandy Silt CPT REPORT - STANDARD - SBT BQ CPT.GPJ LIBRARY 2011_06_28.GDT 4/10/15 15 Page 1 of 1 Electronic Filename: b-2a.cpt -10 S-02A

25 Date: Estimated Water Depth: Rig/Operator: Apr. 5, ft GRB Belville Riverwalk Belville, NC S&ME Project No: Cone Penetration Test S-03 Total Depth: Termination Criteria: Cone Size: 20.2 ft Maximum Reaction Force Depth (ft) 0 Tip Resistance q t (tsf) Sleeve Friction Pore Pressure f s (tsf) u 2 (tsf) u Friction Ratio R f (%) Equivalent N SBT Bq MAI = 4 Elev (ft) Sands-Clean Sand to Silty Sand 0 5 Sands-Clean Sand to Silty Sand Sands-Clean Sand to Silty Sand CPT REPORT - STANDARD - SBT BQ CPT.GPJ LIBRARY 2011_06_28.GDT 4/10/ Page 1 of 1 Electronic Filename: b-3.cpt S-03

26 FIELD TESTING PROCEDURES Soil Test Borings All boring and sampling operations were conducted in accordance with ASTM Designation D Initially, the borings were advanced by either mechanically augering or wash boring through the soils. Where necessary, a heavy drilling fluid is used below the water table to stabilize the side and bottom of the drill hole. At regular intervals soil samples were obtained with a standard 1.4-inch I.D., 2-inch O.D., split-barrel sampler. The sampler was first seated 6 inches to penetrate any loose cuttings and then driven an additional foot with blows of a 140 pound hammer falling 30 inches. The number of hammer blows required to drive the sampler the final foot is designated the "Standard Penetration Resistance." The penetration resistance, when properly evaluated, is an index to the soil strength. Soil Classifications Soil classifications provide a general guide to the engineering properties of various soil types and enable the engineer to apply his past experience to current problems. In our exploration, samples obtained during drilling operations are examined and visually classified according to color, texture, and relative density or consistency (based on standard penetration resistance). The consistency and relative density designations are as follows: SANDS SILTS AND CLAYS N (SPT) Relative Density N (SPT) Consistency 0-4 Very Loose 0-2 Very Soft 5-10 Loose 3-4 Soft Medium Dense 5-8 Firm 9-15 Stiff Dense Very Stiff 50+ Very Dense Hard 50+ Very Hard

27 LEGEND TO SOIL CLASSIFICATION AND SYMBOLS SOIL TYPES (Shown in Graphic Log) Fill Asphalt Concrete Topsoil Gravel Sand Silt Clay CONSISTENCY OF COHESIVE SOILS CONSISTENCY Very Soft Soft Firm Stiff Very Stiff Hard Very Hard RELATIVE DENSITY Very Loose Loose Medium Dense Dense Very Dense STD. PENETRATION RESISTANCE BLOWS/FOOT 0 to 2 3 to 4 5 to 8 9 to to to 50 Over 50 RELATIVE DENSITY OF COHESIONLESS SOILS STD. PENETRATION RESISTANCE BLOWS/FOOT 0 to 4 5 to to to 50 Over 50 Organic Silty Sand Clayey Sand Sandy Silt Clayey Silt SAMPLER TYPES (Shown in Samples Column) Shelby Tube Split Spoon Rock Core No Recovery Sandy Clay Silty Clay Partially Weathered Rock Cored Rock WATER LEVELS (Shown in Water Level Column) Standard Penetration Resistance REC RQD TERMS - The Number of Blows of 140 lb. Hammer Falling 30 in. Required to Drive 1.4 in. I.D. Split Spoon Sampler 1 Foot. As Specified in ASTM D Total Length of Rock Recovered in the Core Barrel Divided by the Total Length of the Core Run Times 100%. - Total Length of Sound Rock Segments Recovered that are Longer Than or Equal to 4" (mechanical breaks excluded) Divided by the Total Length of the Core Run Times 100%. HC = Water Level At Termination of Boring = Water Level Taken After 24 Hours = Loss of Drilling Water = Hole Cave

28 PROJECT: DATE DRILLED: 4/1/15 DRILL RIG: CME 45D-14 DRILLER: Carolina Drilling HAMMER TYPE: Automatic SAMPLING METHOD: Split spoon DRILLING METHOD: Mud Rotary DEPTH (feet) 5 GRAPHIC LOG Belville River Walk Belville, NC S&ME Project No WATER WATER LEVEL 3 FEET ELEVATION: 0.0 ft BORING DEPTH: 43.0 ft WATER LEVEL: 0 MATERIAL DESCRIPTION LOGGED BY: J. Gerdes SANDY LEAN CLAY (CL) with organics, assumed soil type based on B-02, saturated, NO RECOVERY WATER LEVEL ELEVATION (feet) -5.0 SAMPLE NO. BORING LOG SAMPLE TYPE 1st 6in / RUN # B-01 NOTES: Brunswick River water elevation assumed to be 0 feet MSL at time of boring. NORTHING: BLOW COUNT / CORE DATA 2nd 6in / REC 3rd 6in / RQD EASTING: STANDARD PENETRATION TEST DATA (blows/ft) / REMARKS N VALUE CLAYEY SAND (SC) dense, gray, with cemented fragments, fine to medium, saturated SANDY LEAN CLAY (CL) soft, dark gray, saturated SILTY SAND (SM) loose, tan, fine to medium, saturated S&ME BORING LOG SPT.GPJ S&ME.GDT 4/17/ SILTY SAND (SM) very dense, tan, fine to medium, saturated PEEDEE FORMATION: LIMESTONE sampled as limestone fragments and clayey sand, saturated Boring terminated at 43 ft /1" 31 50/1" /1" 50/1" NOTES: THIS LOG IS ONLY A PORTION OF A REPORT PREPARED FOR THE NAMED PROJECT AND MUST ONLY BE USED TOGETHER WITH THAT REPORT. BORING, SAMPLING AND PENETRATION TEST DATA IN GENERAL ACCORDANCE WITH ASTM D STRATIFICATION AND GROUNDWATER DEPTHS ARE NOT EXACT. WATER LEVEL IS AT TIME OF EXPLORATION AND WILL VARY. Page 1 of 1

29 PROJECT: DATE DRILLED: 3/31/15 DRILL RIG: CME 45D-14 DRILLER: Carolina Drilling HAMMER TYPE: Automatic SAMPLING METHOD: Split spoon DRILLING METHOD: Mud Rotary DEPTH (feet) 5 GRAPHIC LOG Belville River Walk Belville, NC S&ME Project No WATER WATER LEVEL 3 FEET ELEVATION: 0.0 ft BORING DEPTH: 38.0 ft WATER LEVEL: 0 MATERIAL DESCRIPTION LOGGED BY: J. Gerdes SANDY LEAN CLAY (CL) very soft, dark gray, with organics, with wood pieces, saturated WATER LEVEL ELEVATION (feet) -5.0 SAMPLE NO. BORING LOG SAMPLE TYPE 1st 6in / RUN # B-02 NOTES: Brunswick River water elevation assumed to be 0 feet MSL at time of boring. NORTHING: BLOW COUNT / CORE DATA 2nd 6in / REC 3rd 6in / RQD EASTING: STANDARD PENETRATION TEST DATA (blows/ft) / REMARKS N VALUE FAT CLAY (CH) very soft, light gray brown, with wood pieces, saturated S&ME BORING LOG SPT.GPJ S&ME.GDT 4/17/ POORLY GRADED SAND (SP) medium dense, tan, with rounded gravel, poorly graded, saturated PEEDEE FORMATION sampled as limestone fragments and clayey sand, saturated Boring terminated at 38 ft /4" /4" NOTES: THIS LOG IS ONLY A PORTION OF A REPORT PREPARED FOR THE NAMED PROJECT AND MUST ONLY BE USED TOGETHER WITH THAT REPORT. BORING, SAMPLING AND PENETRATION TEST DATA IN GENERAL ACCORDANCE WITH ASTM D STRATIFICATION AND GROUNDWATER DEPTHS ARE NOT EXACT. WATER LEVEL IS AT TIME OF EXPLORATION AND WILL VARY. Page 1 of 1

30 PROJECT: DATE DRILLED: 3/31/15 DRILL RIG: CME 45D-14 DRILLER: Carolina Drilling HAMMER TYPE: Automatic SAMPLING METHOD: Split spoon DRILLING METHOD: Mud Rotary DEPTH (feet) 5 GRAPHIC LOG Belville River Walk Belville, NC S&ME Project No WATER WATER LEVEL 3 FEET SANDY ORGANIC CLAY (OH) very soft, gray, saturated ELEVATION: 0.0 ft BORING DEPTH: 43.0 ft WATER LEVEL: 0 MATERIAL DESCRIPTION LOGGED BY: J. Gerdes WATER LEVEL ELEVATION (feet) -5.0 SAMPLE NO. BORING LOG SAMPLE TYPE 1st 6in / RUN # B-03 NOTES: Brunswick River water elevation assumed to be 0 feet MSL at time of boring. NORTHING: BLOW COUNT / CORE DATA 2nd 6in / REC 3rd 6in / RQD EASTING: STANDARD PENETRATION TEST DATA (blows/ft) / REMARKS N VALUE 10 PEAT (PT) very soft, dark brown, saturated SANDY ORGANIC CLAY (OH) very soft, gray brown, with wood, saturated CLAYEY SAND (SC) loose, gray, fine to medium, saturated S&ME BORING LOG SPT.GPJ S&ME.GDT 4/17/ SILTY LEAN CLAY (CL) very soft, dark brown, with wood, saturated POORLY GRADED SAND (SP) medium dense, tan brown, poorly graded, saturated PEEDEE FORMATION sampled as limestone fragments and clayey sand, saturated Boring terminated at 43 ft /12" 1/18" /3" 1/12" 1/18" 13 50/3" NOTES: THIS LOG IS ONLY A PORTION OF A REPORT PREPARED FOR THE NAMED PROJECT AND MUST ONLY BE USED TOGETHER WITH THAT REPORT. BORING, SAMPLING AND PENETRATION TEST DATA IN GENERAL ACCORDANCE WITH ASTM D STRATIFICATION AND GROUNDWATER DEPTHS ARE NOT EXACT. WATER LEVEL IS AT TIME OF EXPLORATION AND WILL VARY. Page 1 of 1

31 PROJECT: DATE DRILLED: 3/31/15 DRILL RIG: CME 45D-14 DRILLER: Carolina Drilling HAMMER TYPE: Automatic SAMPLING METHOD: Split spoon DRILLING METHOD: Mud Rotary DEPTH (feet) 5 GRAPHIC LOG Belville River Walk Belville, NC S&ME Project No WATER WATER LEVEL 3 FEET SANDY ORGANIC CLAY (OH) very soft, dark gray brown, saturated ELEVATION: 0.0 ft BORING DEPTH: 43.0 ft WATER LEVEL: 0 MATERIAL DESCRIPTION LOGGED BY: J. Gerdes WATER LEVEL ELEVATION (feet) -5.0 SAMPLE NO. BORING LOG SAMPLE TYPE 1st 6in / RUN # B-04 NOTES: Brunswick River water elevation assumed to be 0 feet MSL at time of boring. NORTHING: BLOW COUNT / CORE DATA 2nd 6in / REC 3rd 6in / RQD EASTING: STANDARD PENETRATION TEST DATA (blows/ft) / REMARKS N VALUE WOOD SANDY ORGANIC CLAY (OH) very soft, dark gray, with wood, saturated SANDY FAT CLAY (CH) very soft, brown gray, saturated S&ME BORING LOG SPT.GPJ S&ME.GDT 4/17/ POORLY GRADED SAND (SP) medium dense to dense, brown, poorly graded, saturated PEEDEE FORMATION sampled as limestone fragments and clayey sand, saturated Boring terminated at 43 ft /5" /5" NOTES: THIS LOG IS ONLY A PORTION OF A REPORT PREPARED FOR THE NAMED PROJECT AND MUST ONLY BE USED TOGETHER WITH THAT REPORT. BORING, SAMPLING AND PENETRATION TEST DATA IN GENERAL ACCORDANCE WITH ASTM D STRATIFICATION AND GROUNDWATER DEPTHS ARE NOT EXACT. WATER LEVEL IS AT TIME OF EXPLORATION AND WILL VARY. Page 1 of 1