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HomeMy WebLinkAboutSW1191001_18-161 R-S Middle Geotech Report 05 05 2017_10/15/2019PRELIMINARY GEOTECHNICAL ENGINEERING REPORT F3% RUTHERFORDTON-SPINDALE MIDDLE SCHOOL Rutherford County, North Carolina PREPARED FOR: LS3P (for Rutherford County Schools) 227 W. Trade Street, Suite 700 Charlotte, North Carolina 28202 NOVA Project Number: 10705-2017010 May 5, 2017 NOVA PROFESSIONAL I PRACTICAL I PROVEN N OVA May 5, 2017 LS3P (FOR RUTHERFORD COUNTY SCHOOLS) 227 W. Trade Street Suite 700 Charlotte, North Carolina 28202 Attention: Mr. David Bellamy, AIA, LEED AP Architect, Studio Director Subject: Preliminary Geotechnical Engineering Report RUTH ERFORDTON-SPIN DALE MIDDLE SCHOOL Rutherford County, North Carolina NOVA Project Number 10705-2017010 Dear Mr. Bellamy: NOVA Engineering and Environmental, Inc. (NOVA) has completed the authorized Preliminary Geotechnical Engineering Report for the Rutherfordton-Spindale Middle School located in Rutherford County, North Carolina. The work was performed in general accordance with NOVA Proposal Number 005-20166860 Revision 1, dated March 24, 2017. This report briefly discusses our understanding of the project at the time of the subsurface exploration, describes the geotechnical consulting services provided by NOVA, and presents our findings, conclusions, and preliminary recommendations. We appreciate your selection of NOVA and the opportunity to be of service on this project. If you have any questions, or if we may be of further assistance, please do not hesitate to contact us. Sincerely, NOVA Engineering and Environmental, Inc. 1KHrTv Alex Kuczero, E.I. Project Professional Michael Sabodish, Ph.D., P.E. Project Engineer NC P.E. License 029927 Copies Submitted: Addressee (electronic) DRAF David E. Penalva, P.E. Senior Engineer NC P.E. License 038693 PROFESSIONAL I PRACTICAL I PROVEN 5104 Reagan Drive, Suite 8, Charlotte, North Carolina 28226 t. 980.321.4100 / f. 980.321.4099 / usanova.com TABLE OF CONTENTS 1.0 SUMMARY......................................................................................................................1 1.1 GENERAL......................................................................................................................................1 1.2 SITE PREPARATION......................................................................................................................1 1.3 GROUNDWATER CONTROL..........................................................................................................1 1.4 FOUNDATIONS..............................................................................................................................2 1.5 SEISMIC........................................................................................................................................2 1.6 PAVEMENTS..................................................................................................................................2 1.7 SUPPLEMENTAL STUDY...............................................................................................................3 2.0 INTRODUCTION.............................................................................................................. 4 2.1 PROJECT INFORMATION...............................................................................................................4 2.2 SCOPE OF WORK..........................................................................................................................5 3.0 SITE DESCRIPTION......................................................................................................... 7 3.1 LOCATION AND LEGAL DESCRIPTION..........................................................................................7 3.2 SUBJECT PROPERTY AND VICINITY GENERAL CHARACTERISTICS.............................................7 3.3 CURRENT USE OF THE PROPERTY...............................................................................................7 3.4 DESCRIPTIONS OF PROPERTY IMPROVEMENTS........................................................................8 4.0 FIELD AND LABORATORY PROCEDURES....................................................................... 9 4.1 FIELD EXPLORATION....................................................................................................................9 4.2 LABORATORY TESTING..............................................................................................................10 5.0 SUBSURFACE CONDITIONS.........................................................................................12 5.1 GEOLOGY...................................................................................................................................12 5.2 SOILAND ROCK CONDITIONS ...................................................................................................13 5.3 GROUNDWATER CONDITIONS.................................................................................................. 14 6.0 CONCLUSIONS AND RECOMMENDATIONS.................................................................15 6.1 SITE PREPARATION................................................................................................................... 15 6.2 FILL PLACEMENT....................................................................................................................... 17 6.3 GROUNDWATER CONTROL....................................................................................................... 18 6.4 FOUNDATIONS...........................................................................................................................18 6.5 SLAB-ON-GRADE........................................................................................................................20 6.6 PAVEMENT SECTIONS...............................................................................................................21 6.7 SUPPLEMENTAL GEOTECHNICAL STUDY .................................................................................23 7.0 CONSTRUCTION OBSERVATIONS................................................................................25 7.1 SHALLOW FOUNDATIONS......................................................................................................... 25 7.2 SUBGRADE................................................................................................................................ 25 APPENDICES Appendix A - Figures and Maps Appendix B - Subsurface Data Appendix C - Laboratory Data Appendix D - Qualifications of Recommendations Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 1.0 SUMMARY May 5, 2017 NOVA Project Number 10705-2017010 A brief summary of pertinent findings, conclusions, and preliminary recommendations are presented below. This information should not be utilized in design or construction without reading the report in its entirety and paying particular attention to the recommendations presented in the text and Appendix. 1.1 GENERAL The project site is located in Rutherford County, North Carolina. Five (5) soil test borings (B-1 through B-5) were drilled at the subject site during this exploration. Generally, the borings encountered a surface veneer of topsoil and residual soils. • Approximately 2 to 4 inches of topsoil was encountered in all borings performed during this study. Topsoil thickness is frequently erratic and thicker zones of topsoil should be anticipated. • Residual soils were encountered in all borings beneath the topsoil. The residuum consisted of clayey ELASTIC SILT, sandy SILT or silty SAND. Standard penetration resistance values ranged from 7 to 16 bpf. 1.2 SITE PREPARATION Elastic Silts: Based on the limited laboratory testing, elastic silts (Liquid Limits >50 and Plasticity Index >25) were encountered during this exploration. Moisture sensitive soils such as these are not considered suitable for the direct support of structural elements due to the potential for volume change and loss of strength if exposed to changes in moisture. Provided moisture contents are maintained at or near optimum, the plastic soils may be used as backfill in deep fill areas to elevations up to 3 feet below proposed finished subgrade elevation or in non-structural areas. These soils are not suitable for use as backfill within 3 feet below proposed finished subgrade elevations in the building footprint and pavement areas. 1.3 GROUNDWATER CONTROL Groundwater was not encountered in any of the borings performed during this study. N D VA Page 1 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 1.4 FOUNDATIONS May 5, 2017 NOVA Project Number 10705-2017010 For preliminary design purposes, we recommend that a maximum allowable soil bearing pressure of 2,000 to 2,500 pounds per square foot (psf) be used. We note that structural and site grading information was not available at the time of this report. The preliminary design recommendations provided above should be re- evaluated by NOVA once design plans are more advanced and structural and site grading information are available. 1.5 SEISMIC In accordance with Section 1613.3.2 of the 2012 International Building Code (IBC), the seismic Site Class was estimated using the standard penetration resistance values obtained from the soil test borings performed duringthis study. Based upon this analysis, and our knowledge of general subsurface conditions in the area, we believe the soil profiles associated with a Site Class "E" are generally appropriate for this site. We note that structural and site grading information was not available at the time of this report. The preliminary design recommendations provided above should be re- evaluated by NOVA once design plans are more advanced and structural and site grading information are available. 1.6 PAVEMENTS 11 Based on subsurface conditions encountered at this site, the recommended site preparation, an assumed CBR of 3 and the assumed traffic loading conditions and our experience with similar soils, the following pavement sections are recommended: 1.6.1 Asphalt Pavement Pavement Section Standard Duty * Heavy Duty ** Asphaltic Surface Course (9.5 mm SuperPave, NCDOT approved 1 inch 2 inches mix) Asphaltic Base Course (19 mm SuperPave, NCDOT approved 2 inches 2 inches mix) Graded Aggregate Base (GAB) from an approved NCDOT source 6 inches 8 inches N D VA Page 2 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 1.6.2 Concrete Pavement May 5, 2017 NOVA Project Number 10705-2017010 Pavement Section Heavy Duty ** NCDOT approved air -entrained concrete mix 5.5 inches Graded Aggregate Base (GAB) from an approved NCDOT source 4 inches Control Joint Spacing (maximum) 10 feet X 10 feet Saw -Cut Depth (minimum) 1.5 inches We note that vehicle loading conditions and site grading information was not available at the time of this report. The preliminary design recommendations provided above should be re-evaluated by NOVA once design plans are more advanced and structural and site grading information are available. 1.7 SUPPLEMENTAL STUDY Once design plans are more advanced, including column and wall loads, construction locations and elevations, we believe it would be prudent to re -visit the geotechnical data to assess whether or not modifications to the recommendations are necessary. We also recommend a future design meeting between NOVA and other design team members to address geotechnical concerns at specific locations. A final geotechnical exploration should subsequently be performed to provide additional information with regard to site preparation, foundation design recommendations, pavement design recommendations and seismic site classification. N D VA Page 3 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 2.1 PROJECT INFORMATION May 5, 2017 NOVA Project Number 10705-2017010 2.0 INTRODUCTION Our understanding of this project is based on discussions with Mr. David Bellamy with LS3P, review of the provided site plans, a site reconnaissance performed during boring layout, and our experience with similar projects. 2.1.1 Site Plans and Documents We were furnished with the following plans and documents: • Preliminary Rutherfordton-Spindale Middle School Rendering Prepared by: CLH Design, P.A. / LS3P Dated: August 2016 2.1.2 Proposed Construction The proposed construction will consist of a single -story middle school structure consisting of a main building with four expandable wings. We anticipate the structure to be masonry and light -gauge steel construction. Several parking lots and driveways are proposed around the building. A football field, softball field and a stormwater BMP are also proposed as part of the project. This preliminary studywas limited to the proposed building footprint and a section of the proposed parking and drives. 2.1.3 Maximum Loads Structural loading conditions were not provided, however, based on our experience with similar projects we anticipate that loads will be on the order of 2 to 4 kips per lineal foot for wall foundations and on the order of 100 kips for column foundations for the masonry structure. 2.1.4 Floor Elevations / Site Grading No site grading information was available during the time of this study. However, we have assumed that cuts and fills of up to 15 feet will be required within the building pad area based on existing grades. N D VA Page 4 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 2.2 SCOPE OF WORK May 5, 2017 NOVA Project Number 10705-2017010 LS3P engaged NOVA to provide preliminary geotechnica I engineering consulting services for Rutherfordton-Spindale Middle School. This report briefly discusses our understanding of the project, describes our exploratory procedures, and presents our findings, conclusions, and preliminary recommendations. The primary objective of this study was to perform a geotechnical exploration within the area of the proposed construction and to assess these findings as they relate to geotechnical aspects of the planned site development. The authorized geotechnical engineering services included a site reconnaissance, a soil test boring and sampling program, laboratory testing, engineering evaluation of the field and laboratory data, and the preparation of this report. The services were performed substantially as outlined in our proposal number 005- 20166860 Revision 1, dated March 24, 2017, and in general accordance with industry standards. As authorized per the above referenced proposal, the completed geotechnical report was to include: ➢ A description of the site, fieldwork, laboratory testing and general soil conditions encountered, as well as a Boring Location Plan, and individual Boring Records. ➢ Discussion on potential design/construction issues indicated by the exploration, such as old fills, materials that would require difficult excavation techniques, potentially expansive materials, shallow groundwater table, etc. ➢ Recommended quality control measures (i.e. sampling, testing, and inspection requirements) for site grading and foundation construction, including soil compaction requirements. ➢ Recommendations for controlling groundwater and/or run-off during construction and, the need for permanent de -watering systems based on the anticipated post construction groundwater levels ➢ Suitability of on -site soils for re -use as structural fill and backfill. Additionally, the criteria for suitable fill materials will be provided. ➢ Foundation system recommendations for the proposed structures, including allowable bearing capacities and recommended bearing depths. ➢ Pavement design recommendations for heavy and light duty flexible and rigid pavement options based on provided traffic loading and design life expectancy. ➢ Slab -on -grade construction considerations based on the geotechnical findings, including the need for a sub -slab vapor barrier or a capillary barrier. ➢ Preliminary Seismic site classification recommendations using correlation with SPT N-values in accordance with the 2012 IBC. N D VA Page 5 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 The assessment of the presence of wetlands, floodplains, or water classified as State Waters of North Carolina was beyond the scope of this study. Additionally, the assessment of site environmental conditions, including the detection of pollutants in the soil, rock, or groundwater, at the site was also beyond the scope of this geotechnical study. If desired by the client, NOVA can provide these services. -1 N D VA Page 6 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 3.0 SITE DESCRIPTION 3.1 LOCATION AND LEGAL DESCRIPTION The Subject Property is located on the west side of the intersection of Westbrook Drive and Hardin Road in Rutherfordton, Rutherford County, North Carolina. The Subject Property consists of an approximately 93.6-acre site. According to the Rutherford County Geographic Information System (GIS) Database, the Subject Property is identified as Parcel Number 1604452. A Site Location Plan depictingthe location of the Subject Property is included in Appendix A (Figure 1). The approximate latitude and longitude coordinates of the subject site are 35.3995 ° north and 81.9744 ° west, respectively. 3.2 SUBJECT PROPERTY AND VICINITY GENERAL CHARACTERISTICS The generally irregularly shaped Subject Property is located within the Rutherfordton North, North Carolina, United States Geological Survey, 7.5-minute series topographic quadrangle map. Topographically, the Subject Property slopes downward from a high point of approximately 1070 feet above mean sea level (MSL) in the northern portion to approximately 970 feet-MSL in the southern portion of the Subject Property. Grades in the proposed building area generally slope downward from the east towards the west from approximately 1054 feet-MSL to 1040 feet MSL. The vicinity of the Subject Property is generally developed with residential land uses, and is bordered by the following: DIRECTION LAND USE DESCRIPTION/OBSERVATIONS NORTH Residential / Agricultural Area EAST R-S High School / Agricultural Area SOUTH Residential / Agricultural Area WEST Residential / Agricultural Area 3.3 CURRENT USE OF THE PROPERTY The Subject Property is currently mostly used as an area to raise livestock by Rutherfordton-Spindale High School, which is adjacent to the site. The north side of the property is currently used as a baseball field. N D VA Page 7 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 3.4 DESCRIPTIONS OF PROPERTY IMPROVEMENTS May 5, 2017 NOVA Project Number 10705-2017010 The Subject Property is currently mostly undeveloped wooded area. A small, open - sided shed is located in the center of the site and is surrounded by livestock pens. Majority of the wooded area is fenced and used to keep livestock. A baseball field with a metal building occupy the north portion of the property. 7 N D VA Page 8 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 4.0 FIELD AND LABORATORY PROCEDURES 4.1 FIELD EXPLORATION Boring locations were established in the field by NOVA personnel using the provided site plan, a handheld GPS device and estimating/taping distances and angles from existing site landmarks. The approximate locations are shown on Figure 2 in Appendix A. Boring elevations were then interpolated from the topographical survey prepared by CLH Design, P.A. and dated August 2016. Consequently, referenced boring locations and elevations are approximate. If increased accuracy is desired by the client, NOVA recommends that the boring locations and elevations be surveyed by a licensed North Carolina Surveyor. Our field exploration was conducted during the period April 4 to April 5, 2017 and included: • Five (5) soil test borings (B-1 through B-5) drilled to depths of 20.0 to 50.0 feet below the existing ground surface. Soil Test Borings: The soil test borings were performed using the guidelines of ASTM Designation D-1586, "Penetration Test and Split -Barrel Sampling of Soils". A hollow -stem auger drilling process was used to advance the borings. At regular intervals, soil samples were obtained with a standard 1.4-inch I.D., 2.0-inch O.D., split -tube sampler. The sampler was first seated six inches 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 "Penetration Resistance". The penetration resistance, when properly interpreted, is an index to the soil strength and density. Representative portions of the soil samples, obtained from the sampler, were placed in glass jars and transported to our laboratory for further evaluation and laboratory testing. Test Boring Records in Appendix B show the standard penetration test (SPT) resistances, or "N-values", and present the soil conditions encountered in the borings. These records represent our interpretation of the subsurface conditions based on the field exploration data, visual examination of the split -barrel samples, laboratory test data, and generally accepted geotechnical engineering practices. The stratification lines and depth designations represent approximate boundaries between various subsurface strata. Actual transitions between materials may be gradual. Groundwater: The groundwater levels, if encountered, reported on the Test Boring Records represent measurements made at the completion of the soil test boring and 24 hours thereafter. The soil test borings were subsequently backfilled with the soil cuttings. N D VA Page 9 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 4.2 LABORATORY TESTING May 5, 2017 NOVA Project Number 10705-2017010 Laboratory testing was conducted to characterize materials encountered at the site using split -barrel samples recovered from the site. The laboratory test data are presented in Appendix C. Selected test data are presented on the Boring Records attached in Appendix B. The specific tests are briefly described below. It should be noted that all soil samples would be properly disposed of 30 days following the submittal of this NOVA subsurface exploration report unless you request otherwise. 4.2.1 Soil Classification Soil classification provides a general guide to the engineering properties of various soil types and enable the engineer to apply past experience to current problems. In our explorations, samples obtained during drilling operations are observed in our laboratory and visually classified by an engineer. The soils are classified according to consistency (based on number of blows from standard penetration tests), color and texture. These classification descriptions are included on our "Test Boring Records". The classification system discussed above is primarily qualitative; laboratory testing is generally performed for detailed soil classification. Usingthe test results, the soils were classified using the Unified Soil Classification Systems. This classification system and the in -place physical soil properties provide an index for estimating the soil's behavior. The soil classification and physical properties obtained are presented in this report. 4.2.2 Moisture Content The moisture content is the ratio expressed as a percentage of the weight of water in a given mass of soil to the weight of the solid particles. This test was conducted in general accordance with ASTM D 2216. A total of four (4) moisture content tests were performed in this study. 4.2.3 Sieve Analysis The sieve analysis consists of passing a soil sample through a series of standard sieve openings. The percentage of soil, by weight, passing the individual sieves is then recorded and generally presented in a graphical format. The percentage of fines passing through the No. 200 sieve is generally considered to represent the amount of silt and clay of the tested soil sample. The sieve analysis test was conducted in general accordance with ASTM Designation D 1140. A total of four (4) sieve analysis tests were performed in this study. N D VA Page 10 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 4.2.4 Atterberg Limits May 5, 2017 NOVA Project Number 10705-2017010 The Atterberg Limits are different descriptions of the moisture content of fine- grained soils as it transitions between a solid to a liquid -state. For classification purposes the two primary Atterberg Limits used are the plastic limit (PL) and the liquid limit (LL). The plastic index (PI) is also calculated for soil classification. The plastic limit (PL) is the moisture content at which a soil transitions from being in a semisolid state to a plastic state. The liquid limit (LL) is defined as the moisture content at which a soil transitions from a plastic state to a liquid state. Four (4) tests were performed in this study in accordance with ASTM D4318 - Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils. Table 1: Summary of Laboratory Test Results Boring Depth �ft) Atterberg %Fines Natural Moisture USCS LL PL PI B-1 1.0 81 39 42 84.2 34.3% MH B-2 6.0 46 40 6 64.3 27.5% ML B-4 1.0 83 41 42 80.5 36.4% MH B-5 1.0 1 79 1 41 1 38 1 82.1 1 34.0% 1 MH N D VA Page 11 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 5.1 GEOLOGY May 5, 2017 NOVA Project Number 10705-2017010 5.0 SUBSURFACE CONDITIONS The site is located in the Inner Piedmont Belt of the Piedmont Physiographic Provence, a broad northeasterly trending province underlain by crystalline rocks up to 600 million years old. The Piedmont is bounded on the northwest by the Blue Ridge Range of the Appalachian Mountains, and on the southeast by the Coastal Plain. According to the "Geologic Map of North Carolina: Department of Natural Resources and Community Development, Division of Land Resources, and the NC Geological Survey" by Rhodes and Conrad, 1985, the site is generally underlain by Metavolcanic Rock. This geologic formation typically consists of felsic metavolcanic and mafic metavolcanic rock of the Cambrian and Late Proterozoic era. Residual soils in the region are primarily the product of in -situ chemical decomposition of the parent rock. The extent of the weathering is influenced by the mineral composition of the rock and defects such as fissures, faults and fractures. The residual profile can generally be divided into three zones: • An upper zone near the ground surface consisting of red clays and clayey silts which have undergone the most advanced weathering, • An intermediate zone of less weathered micaceous sandy silts and silty sands, frequently described as "saprolite", whose mineralogy, texture and banded appearance reflects the structure of the original rock, and • A transitional zone between soil and rock termed partially weathered rock (PWR). Partially weathered rock is defined locally by standard penetration resistances exceeding 100 blows per foot. The boundaries between zones of soil, partially weathered rock, and bedrock are erratic and poorly defined. Weathering is often more advanced next to fractures and joints that transmit water, and in mineral bands that are more susceptible to decomposition. Boulders and rock lenses are sometimes encountered within the overlying PWR or soil matrix. Consequently, significant fluctuations in depths to materials requiring difficult excavation techniques may occur over short horizontal distances. N D VA Page 12 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 5.2 SOIL AND ROCK CONDITIONS May 5, 2017 NOVA Project Number 10705-2017010 The following paragraphs provide generalized descriptions of the subsurface profiles and soil conditions encountered by the borings conducted during this study. The Test Boring Records in Appendix B should be reviewed to provide more detailed descriptions of the subsurface conditions encountered at each boring location. These records represent our interpretation of the subsurface conditions based on the field logs and visual observations of samples by an engineer. The lines designating the interface between various strata on the Boring Records represent the approximate interface locations and elevation. The actual transition between strata may be gradual. Groundwater levels shown on the Boring Records represent the conditions at the time of drilling. It should be understood that soil conditions may vary between boring locations. 5.2.1 Surface Materials Topsoil: Approximately 2 to 4 inches of topsoil was encountered in all borings performed during this study. Topsoil thickness is frequently erratic and thicker zones of topsoil should be anticipated. 5.2.2 Residual Soils Residual soils were encountered in all borings beneath the topsoil. The residuum consisted of clayey ELASTIC SILT, sandy SILT or silty SAND. Standard penetration resistance values ranged from 7 to 16 bpf. 5.2.3 Plastic Soils Based on the limited laboratory testing, elastic silts (Liquid Limits >50 and Plasticity Index >25) were encountered during this exploration at borings B-1, B- 2, B-4 and B-5 to depths of approximately 6.0 feet below existing grades. These types of soils are not considered suitable for the direct support of structural elements due to the potential for volume change and loss of strength if exposed to changes in moisture. Provided moisture contents are maintained at or near optimum, the plastic soils may be used as backfill in deep fill areas to elevations up to 3 feet below proposed finished subgrade elevation or in non-structural areas. These soils are not suitable for use as backfill within 3 feet below proposed finished subgrade elevations in the building footprint and pavement areas. N D VA Page 13 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School 5.3 GROUNDWATER CONDITIONS 5.3.1 General May 5, 2017 NOVA Project Number 10705-2017010 Groundwater in the Piedmont typically occurs as an unconfined or semi -confined aquifer condition. Recharge is provided by the infiltration of rainfall and surface water through the soil overburden. More permeable zones in the soil matrix, as well as fractures, joints and discontinuities in the underlying bedrock can affect groundwater conditions. The groundwater table in the Piedmont is expected to be a subdued replica of the original surface topography. Groundwater levels vary with changes in season and rainfall, construction activity, surface water runoff, and other site -specific factors. Groundwater levels in the Rutherford County area are typically lowest in the late summer -early fall and highest in the late winter -early spring, with annual groundwater fluctuations of 4 to 8 feet; consequently, the water table may vary at times. 5.3.2 Soil Test Boring Groundwater Conditions Groundwater was not encountered in any of the borings performed during this study. Boring B-3 caved upon retrieval of the augers at a depth of approximately 42 feet below existing grade. Caved depths may be indicative of groundwater levels and have been included on the Test Boring Records in Appendix B. N D VA Page 14 Preliminary Geotechnical Engineering Report May 5, 2017 Rutherfordton-Spindale Middle School NOVA Project Number 10705-2017010 6.0 CONCLUSIONS AND RECOMMENDATIONS The following conclusions and recommendations are based on our understanding of the proposed construction, site observations, our evaluation and interpretation of the field and laboratory data obtained during this exploration, our experience with similar subsurface conditions, and generally accepted geotechnical engineering principles and practices. Subsurface conditions in unexplored locations or at other times may vary from those encountered at specific boring locations. If such variations are noted during construction, or if project development plans are changed, we request the opportunity to review the changes and amend our recommendations, if necessary. As previously noted, boring locations were established by estimating distances and angles from site landmarks. If increased accuracy is desired by the client, we recommend that the boring locations and elevations be surveyed by a licensed North Carolina Surveyor. 6.1 SITE PREPARATION 6.1.1 General Prior to proceedingwith construction; vegetation, root systems, topsoil, and other deleterious non -soil materials should be stripped from proposed construction areas. Clean topsoil may be stockpiled and subsequently re -used in landscaped areas. Debris -laden materials should be excavated, transported, and disposed of off -site in accordance with appropriate solid waste rules and regulations. All existing utility locations should be reviewed to assess their impact on the proposed construction and relocated/grouted in -place as appropriate. After clearing and stripping, areas, which are at grade or will receive fill should be carefully evaluated by a NOVA geotechnical engineer. The engineer will require proofrolling of the subgrade with multiple passes of a 20 to 30 ton loaded truck, a 10 to 12 ton vibratory roller, or other vehicle of similar size and weight. Vibratory compaction should be turned off and static rolling should be performed if yielding conditions appear. The purpose of the proofrolling is to locate unstable materials, such as soft, weak, or excessively wet fill or residual soils present at the time of construction. Unstable materials observed during the evaluation and proof -rolling operations should be undercut and replaced with structural fill or stabilized in -place by scarifying and re-densifying. N D VA Page 15 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 In the event that low consistency and/or debris laden fill materials are encountered during construction, typical recommendations would include undercutting and backfilling with structural fill and/or stabilizing in -place with fabric, stone, and/or other remedial techniques. Actual remedial recommendations can best be determined by the geotechnical engineer in the field at the time of construction. The site should be graded during construction such that positive drainage is maintained away from the construction areas, to prevent ponding of storm water on the site during and shortly following significant rain events. The construction areas should also be sealed and crowned with a smooth roller to minimize ponding water from storm events at the end of each day of work. 6.1.2 Plastic Soils Plastic silts were encountered in four (4) of the borings drilled in this study to depths of 6.0 feet below existing grade. We note that the current geotechnical investigation consisted of widely spaced borings and limited laboratory testing. Expansive soils should be expected at other areas across the site. Plastic soils are expansive and will swell or shrink upon increasing or decreasing moisture content, respectively, leading to potential structural damages. In addition, these soils have the potential to lose some of their strength when exposed to the combination of wet weather and construction traffic. The severity of these potential problems depends to a great extent on the weather conditions during construction. Aconcerted effort should be made to control construction traffic and surface water while subgrade soils are exposed. Soils with a high plasticity are not considered suitable for the direct support of structural elements due to the potential for swell and loss of strength if exposed to changes in moisture. Therefore, if encountered within the building footprint or pavement areas, we recommend a limited undercutting program at the site as described below: • Undercutting subgrade soils to provide 3 feet of separation from foundations, slabs or pavements; • Provided moisture contents are maintained at or near optimum, the plastic soils may be used as backfill in deep fill areas to elevations up to 3 feet below proposed finished subgrade elevation or in non-structural areas. These soils are not suitable for use as backfill within 3 feet below proposed finished subgrade elevations in the building footprint and pavement areas. N D VA Page 16 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 • Following undercutting, densification (compaction) of the subsequently exposed soils should be performed. Compaction should be performed under the observation and assessment of NOVA's geotechnical engineer who will document that proper densification has been achieved. • After the in -place densification is completed, non -plastic soils can be used as structural backfill. The soils should be placed in 8 to 10-inch loose lifts and compacted to a minimum 95 percent of the soil's modified Proctor maximum dry density (ASTM D-1557). NOVA's representative should be on site during backfilling to perform field density tests to confirm that the required compaction is achieved. Other options, such as the addition of lime or cement, may be feasible for stabilizing the plastic soils. The impact of plastic soils and possible stabilization methods should be reviewed once site plans are more developed. 6.2 FILL PLACEMENT 6.2.1 Fill Suitability Fill materials should be low plasticity soil (Plasticity Index less than 30), free of non -soil materials and rock fragments larger than 3 inches in any one dimension. Based on visual examination and limited laboratory testing, the existing residual soils, except for the elastic silt soils, encountered during this exploration generally appear suitable for re -use as structural fill, provided they are placed at a moisture content suitable to achieve proper compaction. All materials to be used for backfill or compacted fill construction should be evaluated and, if necessary, tested by NOVA prior to placement to determine if they are suitable for the intended use. Any off -site materials used as fill should be approved by NOVA prior to acquisition. Organic and/or debris -laden material is not suitable for re -use as structural fill. Topsoil, mulch, and similar organic materials can be wasted in architectural areas. Debris -laden materials should be excavated, transported, and disposed of off -site in accordance with appropriate solid waste rules and regulations. 6.2.2 Soil Compaction Fill should be placed in thin, horizontal loose lifts (maximum 8-inch) and compacted to at least 95 percent of the standard Proctor maximum dry density (ASTM D 698). The upper 12 inches of soil beneath pavements and slab-on- N D VA Page 17 Preliminary Geotechnical Engineering Report May 5, 2017 Rutherfordton-Spindale Middle School NOVA Project Number 10705-2017010 grade should be compacted to at least 98 percent. In confined areas, such as utility trenches or behind retaining walls, portable compaction equipment and thinner fill lifts (3 to 4 inches) may be necessary. Fill materials used in structural areas should have a target maximum dry density of at least 95 pounds per cubic foot (pcf). If lighter weight fill materials are used, the NOVA geotechnical engineer should be consulted to assess the impact on design recommendations. Soil moisture content should be maintained within 3 percent of the optimum moisture content. Based on limited laboratory testing, moisture conditioning of the onsite soil may be required prior to being placed as structural fill. We recommend that the grading contractor have equipment on site during earthwork for both drying and wetting the fill soils. Moisture control may be difficult during rainy weather. Fill placement and compaction operations should be observed by a NOVA soils technician, who can confirm suitability of material used and uniformity and appropriateness of compaction efforts. He/she can also document compliance with the specifications by performing field density tests using thin -walled tube, nuclear, or sand cone testing methods (ASTM D 2937, D 2922, or D 1556, respectively). One test per 400 cubic yards and every 1 foot of placed fill is recommended, with test locations well distributed throughout the fill mass. When filling in small areas, at least one test per day per area should be performed. ` 6.3 GROUNDWATER CONTROL • Groundwater was not encountered during this exploration in any of the borings above boring termination depths of 30.0 to 50.0 feet. Based on the assumed cuts necessary to reach design subgrades, we do not anticipate significant groundwater control problems during mass grading operations. 6.4 FOUNDATIONS Preliminary Design: After the recommended site and subgrade preparation and fill placement, we recommend that the proposed structure be supported by conventional shallow foundations. Foundations bearing on undisturbed residual soils and/or compacted structural fill may be designed for a maximum allowable bearing pressure of 2,000 to 2,500 pounds per square foot (psf). The aforementioned bearing pressure is based on the foundation bottoms being compacted to 95% of the Modified Proctor maximum dry density to a minimum depth of 2 feet below the foundation bearing surface. N D VA Page 18 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 We recommend minimum foundation widths of 24 inches for ease of construction and to reduce the possibility of localized shear failures. Exterior foundation bottoms should be at least 18 inches below exterior grades for protection against frost damage. Settlement: Settlements for spread foundations bearing on residual materials were assessed usingSPTvalues to estimate elastic modulus, based on published correlations and previous NOVA experience. We note that the settlements presented are based on random field data and an assumed subsoil profile. Conditions may be better or worse in other areas, however, we believe the estimated settlements are reasonably conservative. Based on assumed column loadings, soil bearing capacities and the presumed foundation elevations as discussed above, we expect primary total settlement beneath individual foundations to be on the order of 1 to 11/2 inches. The amount of differential settlement is difficult to predict because the subsurface and foundation loading conditions can vary considerably across the site. However, we anticipate differential settlement between adjacent foundations could vary from 1/2 to 3/4 inch. The final deflected shape of the structure will be dependent on actual foundation locations and loading. To reduce the differential settlement if lower consistency materials are encountered, a lower bearing capacity should be used or the foundations should be extended to more competent materials. In addition, foundation subgrades which are excavated into dense materials may need to be slightly undercut with controlled structural fill placed between the dense materials and the bottom of the foundation to produce some settlement of the foundation, thus reducing differential settlements with nearby foundations bearing on less dense material. We anticipate that timely communication between the geotechnical engineer and the structural engineer, as well as other design and construction team members, will be required. We note that structural information was not available at the time of this report The preliminary design recommendations provided above should be re-evaluated by NOVA once design plans are more advanced and structural and site grading information are available. The above recommendations and settlement estimates should be considered preliminary. Construction: Foundation excavations should be evaluated by the NOVA geotechnical engineer prior to reinforcing steel placement to observe foundation subgrade preparation and confirm bearing pressure capacity. Foundation excavations should be level and free of debris, ponded water, mud, and loose, frozen, or water -softened soils. Concrete should be placed as soon as is N D VA Page 19 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 practical after the foundation is excavated and the subgrade evaluated. Foundation concrete should not be placed on frozen or saturated soil. If a foundation excavation remains open overnight, or if rain or snow is imminent, a 3 to 4-inch thick "mud mat" of lean concrete should be placed in the bottom of the excavation to protect the bearing soils until reinforcing steel and concrete can be placed. 6.5 SLAB -ON -GRADE 6.5.1 General The conditions exposed at subgrade levels will vary across the site and may include structural fill or residual soils. Slabs -on -grade may be adequately supported on these subgrade conditions subject to the recommendations in this report. Slabs -on -grade should be jointed around columns and along walls to reduce cracking due to differential movement. An underdrain system is not required. However, we recommend a minimum of 6-inches of graded aggregate base (GAB) beneath the slabs to: • Reduce non -uniform support conditions • Provide a stable base to support construction traffic • Provide a base material that can be fine graded to design tolerances. GAB should be compacted to 98 percent of the maximum dry density as determined by the modified Proctor compaction test (ASTM D 1557) and overlain by a conventional plastic vapor barrier. The plastic soils encountered on the site are not suitable for the direct support of structural elements due to the potential for swell and loss of strength if exposed to changes in moisture. Should these soils be encountered at or near proposed finished grade elevations some over excavation and replacement should be anticipated to maintain a separation of 3 feet between the expansive soils and slabs. If these materials are encountered, a geotechnical engineer should evaluate the soils for unstable conditions. Once grading is completed, the subgrade is usually exposed to adverse construction activities and weather conditions during the period of sub -slab utility installation. The subgrade should be well -drained to prevent the accumulation of water. If the exposed subgrade becomes saturated or frozen, the geotechnical engineer should be consulted. After utilities have been installed and backfilled, a final subgrade evaluation should be performed by the geotechnical engineer immediately prior to slab-on- N D VA Page 20 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 grade placement. If practical, proofrolling may be used to redensify the surface and to detect any soil that has become excessively wet or otherwise loosened. We note that structural loading and site grading information was not available at the time of this report. The preliminary design recommendations provided above should be re-evaluated by NOVA once design plans are more advanced and structural and site grading information are available. 6.6 PAVEMENT SECTIONS 6.6.1 Flexible Pavement At the time of this report, traffic loading conditions have not been provided. For preliminary design purposes the following traffic loading conditions have been assumed based on the proposed number of parking spaces: • Standard Duty: 500 automobiles per day for 7 days per week with the occasional delivery truck. • Heavy Duty: 500 automobiles and 25 buses per day for 7 days per week with the occasional delivery truck. Based on subsurface conditions encountered at this site, the recommended site preparation, an assumed CBR of 3 and the assumed traffic loading conditions and our experience with similar soils, the following flexible pavement sections are recommended: Pavement Section Standard Duty * Heavy Duty ** Asphaltic Surface Course (9.5 mm SuperPave, NCDOT approved 1 inch 2 inches mix) Asphaltic Base Course (19 mm SuperPave, NCDOT approved 2 inches 2 inches mix) Graded Aggregate Base (GAB) from an approved NCDOT source 6 inches 9 inches * Standard Duty - Driveways and parking lots restricted to automobile traffic ** Heavy Duty -Driveways and parking lots subject to automobile and truck traffic N D VA Page 21 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 We recommend a minimum compaction of 100 percent of the maximum dry density for the crushed stone material Graded Aggregate Base (GAB) as determined by the modified Proctor compaction test (ASTM D 1557, Method D). The crushed stone should conform to applicable sections of the current NCDOT Standard Specifications. All asphalt material and paving operations should meet applicable specifications of the Asphalt Institute and NCDOT. A NOVA technician should observe placement and compaction activities and perform density testing of the base course material and asphalt. 6.6.2 Rigid Pavement Based on the subsurface conditions at the site, assumed traffic loading conditions and an estimated subgrade modulus (k) of 125 psi/inch for traffic or wheel loading, our recommended rigid pavement design in the dumpster area and areas of heavy breaking or turning is as follows: Pavement Section Heavy Duty ** NCDOT approved air -entrained concrete mix 5.5 inches Graded Aggregate Base (GAB) from an approved NCDOT source 4 inches Control Joint Spacing (maximum) 10 feet X 10 feet Saw -Cut Depth (minimum) 1.5 inches MEM ** Heavy Duty -Driveways and parking lots subject to automobile and truck traffic All concrete materials and placement should conform to applicable NCDOT specifications. We recommend that a non -woven geotextile (about 3 feet wide) be placed beneath the construction joints to prevent upward "pumping' movement of soil fines through the joints. We recommend using concrete with a minimum compressive strength of 4000 psi and a minimum 28-day flexural strength (modulus of rupture) of at least 600 pounds per square inch, based on 3rd point loading of concrete beam test samples. Layout of the saw -cut control joints should form square panels, and the depth of saw -cut joint should be approximately 1/4 of the concrete slab thickness. The joints should be sawed within six (6) hours of concrete placement N D VA Page 22 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 or as soon as the concrete has developed sufficient strength to support workers and equipment. We recommend allowing NOVA to review and comment on the final concrete pavement design, including section and joint details (type of joints, joint spacing, etc.), prior to the start of construction. For further details on concrete pavement construction, please reference the "Guide to Jointing on Non -Reinforced Concrete Pavements" published by the Florida Concrete and Products Associates, Inc., and "Building Quality Concrete Parking Areas", published by the Portland Cement Association. Please note that the recommended pavement sections are based on assumed post - construction traffic loadings. If the pavement is to be constructed and utilized by construction traffic, the above pavement sections will likely prove insufficient for heavy truck traffic, such as concrete trucks or tractor -trailers used for construction delivery. Unexpected distress, reduced pavement life and /or pre -mature failure of the pavement section could result if subjected to heavy construction traffic and the owner should be made aware of this risk. If the assumed traffic loading stated herein is not correct, NOVA should review actual pavement loading conditions to determine if revisions to these recommendations are warranted. We note that vehicle loading conditions and site grading information was not available at the time of this report. The preliminary design recommendations provided above should be re-evaluated by NOVA once design plans are more advanced and structural and site grading information are available. 6.7 SUPPLEMENTAL GEOTECHNICAL STUDY Once design plans are more advanced, including column and wall loads, construction locations and elevations, we believe it would be prudent to re -visit the geotechnical data to assess whether or not modifications to the recommendations are necessary. We also recommend a future design meeting between NOVA and other design team members to address geotechnical concerns at specific locations. A final geotechnical exploration should subsequently be performed to provide additional information with regard to site preparation, excavation, groundwater conditions, and foundation design recommendations. Based on the subsurface conditions encountered in the borings performed for this study, it may be prudent to provide a seismic site class through in -situ shear -wave velocity profiling. Shear -wave velocity profiles can be obtained utilizing a geophone array spread across the ground surface. Ambient seismic "noise", also known as microtremors, is constantly created by cultural and natural noise. These microtremors are recorded using the geophone array. Several noise records are obtained during the N D VA Page 23 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 survey. The wavefield transformation of the noise record is obtained from commercially available software. The shear -wave dispersion curve is manually "picked" from the wavefield transformation, and the picks are modeled to determine the shear -wave velocity profile. N D VA Page 24 Preliminary Geotechnical Engineering Report Rutherfordton-Spindale Middle School May 5, 2017 NOVA Project Number 10705-2017010 7.0 CONSTRUCTION OBSERVATIONS 7.1 SHALLOW FOUNDATIONS Foundation excavations should be level and free of debris, ponded water, mud, and loose, frozen or water -softened soils. All foundation excavations should be evaluated by the NOVA geotechnical engineer prior to reinforcing steel placement to observe foundation subgrade preparation and confirm bearing pressure capacity. Due to variable site subsurface and construction conditions, some adjustments in isolated foundation bearing pressures, depth of foundations or undercutting and replacement with controlled structural fill may be necessary. 7.2 SUBGRADE Once site grading is completed, the subgrade may be exposed to adverse construction activities and weather conditions. The subgrade should be well -drained to prevent the accumulation of water. If the exposed subgrade becomes saturated or frozen, the NOVA geotechnical engineer should be consulted. A final subgrade evaluation should be performed by the NOVA geotechnical engineer immediately prior to pavements or slab -on -grade placement. If practical, proofrolling may be used to re-densify the surface and to detect any soil, which has become excessively wet or otherwise loosened. N D VA Page 25 APPENDIX A Figures and Maps 41 -N f EM to ki t4P, oil v uth T z 4w T Np,.Ie ON u o dt 4.1 PA SOURCE: Preliminary "Rutherford-Spindale Middle School" Rendering prepared by CLH Design, P.A. / LS3P Locations were approximated in the field using a hand-held GPS and taping/pacingfrom existingsite landmarks SCALE: Not to Scale Figure 2: Boring Location Plan Rutherford-Spindale Middle School VA Rutherford County, North Carolina N 13NOVA Project Number: 10705-2017010 APPENDIX B Subsurface Data Ifts KEY TO SYMBOLS AND CLASSIFICATIONS DRILLING SYMBOLS Split Spoon Sample a Undisturbed Sample (UD) Standard Penetration Resistance (ASTM D1586) 1 Water Table at least 24 Hours after Drilling Q Water Table 1 Hour or less after Drilling 100/2" Number of Blows (100) to Drive the Spoon a Number of Inches (2) NX, NQ Core Barrel Sizes: 2Y8- and 2-Inch Diameter Rock Core, Respectively REC Percentage of Rock Core Recovered RQD Rock Quality Designation — Percentage of Recovered Core Segments 4 or more Inches Long 01 Loss of Drilling Water MC Moisture Content Test Performed CORRELATION OF PENETRATION RESISTANCE WITH RELATIVE DENSITY AND CONSISTENCY Number of Blows, "N" Approximate Relative Density 0-4 Very Loose 5 —10 Loose SANDS 11-30 Medium Dense 31— 50 Dense Over 50 Very Dense Number of Blows, "N" Approximate Consistency 0-2 Very Soft 3-4 Soft SILTS 5-8 Firm and 9 —15 Stiff CLAYS 16 — 30 Very Stiff 31— 50 Hard Over 50 Very Hard DRILLING PROCEDURES Soil sampling and standard penetration testing performed in accordance with ASTM D1586. The standard penetration resistance is the number of blows of a 140 pound hammer falling 30 inches to drive a 2-inch O.D., I% - inch I.D. split spoon sampler one foot. Core drilling performed in accordance with ASTM D2113. The undisturbed sampling procedure is described by ASTM D1587. Soil and rock samples will be discarded 30 days after the date of the final report unless otherwise directed. N ❑ VA SOIL CLASSIFICATION CHART COARSE GRAINED SOILS GRAVELS Clean Gravel less than 5%fines GW Well graded gravel GP Poorly graded gravel Gravels with Fines more than 12%fines GM Silty gravel GC Clayey gravel SANDS Clean Sand less than 5%fines SW Well graded sand SP Poorly graded sand Sands with Fines more than 12%fines SM Silty sand SC Clayey sand FINE GRAINED SOILS SILTS AND CLAYS Liquid Limit less than 50 Inorganic CL Lean clay ML Silt Organic OL Organic clay and silt SILTS AND CLAYS Liquid Limit 50 or more Inorganic CH Fat clay MH Elastic silt Organic OH Organic clay and silt HIGHLY ORGANIC SOILS Organic matter, dark color, organic odor PT Peat PARTICLE SIZE IDENTIFICATION GRAVELS Coarse % inch to 3 inches Fine No. 4 to % inch SANDS Coarse No. 10 to No. 4 Medium No. 40 to No. 10 Fine No. 200 to No. 40 SILTS AND CLAYS Passing No. 200 N ❑ VA N OVA TEST BORING RECORD B_1 PROJECT: Rutherfordton-Spindale Middle School PROJECT NO.: 2017010 CLIENT: LS3P for Rutherford County Schools PROJECT LOCATION: Rutherfordton, North Carolina LOCATION: Proposed Parking Lot ELEVATION: 1047 ft-MSL+/ DRILLER: FST LOGGED BY: A.Kuczero DRILLING METHOD: Diedrich D-50 HSA DATE: 4/5/2017 DEPTH TO - WATER> INITIAL: s DRY AFTER 24 HOURS: s DRY CAVING> -L N/A c O J w Description U �_ O 2 N T z Graphic Depiction • BLOW . NATURAL PLASTIC 10 COUNT MOISTURE LIMIT 20 LIQUID 60 LIMIT 10 0 104 104 103 103 102 102 101 Topsoil (4 inches) 4-5-� 4- 3-4-4 3-6-6 4-3-5 30 40 12 12 • i RESIDUUM: Moist, stiff, reddish brown, micaceous, clayey ELASTIC SILT (MH) with some fine sand 5 8 11 Moist, stiff, reddish brown, micaceous, fine sandy SILT (ML) Moist, loose to medium dense, orange and brown, micaceous, siltyfine to medium SAND (SM) 10 12 15 8 20 Boring Terminated at 20.0 feet 25 30 35 Page 1 of 1 a) N H N OVA TEST BORING RECORD B-2 c O J >� 0 104( 5 103! 10 103 PROJECT: Rutherfordton-Spindale Middle School PROJECT NO.: 2017010 CLIENT: LS3P for Rutherford County Schools PROJECT LOCATION: Rutherfordton, North Carolina LOCATION: Proposed Building Pad ELEVATION: 1043 ft-MSL +/ DRILLER: FST LOGGED BY: A.Kuczero DRILLING METHOD: Diedrich D-50 HSA DATE: 4/5/2017 DEPTH TO - WATER> INITIAL: s DRY AFTER 24 HOURS: s DRY CAVING> -L N/A Graphic Depiction Description �_ E T BLOW COUNT P ' � o NATURAL MOISTURE cD PLASTIC LIMIT ILIQUID LIMIT 10 20 30 40 60 10 Topsoil (3 inches) _ RESIDUUM: Moist, stiff, reddish brown, micaceous, fine sandy ELASTIC SILT (MH) with some clay Moist, firm, orange and brown, highly micaceous, fine sandy SILT (ML) Moist, loose to medium dense, red and brown, highly micaceous, siltyfine to medium SAND (SM) 102 102 101 101 Boring Terminated at 20.0 feet If 9 3-4-5 4 8 3-4-4 0 7 3-3-4 0 9 3-4-5 41 12 5-6-6 0 N OVA TEST BORING RECORD B_3 PROJECT: Rutherfordton-Spindale Middle School PROJECT NO.: 2017010 CLIENT: LS3P for Rutherford County Schools PROJECT LOCATION: Rutherfordton, North Carolina LOCATION: Proposed Building Pad ELEVATION: 1050ft-MSL+/ DRILLER: FST LOGGED BY: A.Kuczero DRILLING METHOD: Diedrich D-50 HSA DATE: 4/5/2017 DEPTH TO - WATER> INITIAL: s DRY AFTER 24 HOURS: = DRY CAVING> -L 42.0' c O J w Description U �_ O 2 N T z Graphic Depiction • BLOW . NATURAL PLASTIC 10 COUNT MOISTURE LIMIT 20 LIQUID 60 LIMIT 10 0 105 104E 104C 103 103 102 102 101 Topsoil (2 inches) 4-5-7 4-4-5 3-4-4 3-4-4 4-5-6 4-5-6 3-4-4 2-4-6 5-8-8 30 40 9 • 12 RESIDUUM: Moist, stiff to firm, reddish brown, micaceous, fine sandy SILT (ML) Moist, firm, tan and brown, highly micaceous, fine sandy SILT (ML) 5 8 0 8 10 11 15 11 20 8 25 0 Moist, loose to medium dense, brown, highly micaceous, silty fine SAND (SM) 30 16 35 Page 1 of 2 N OVA TEST BORING RECORD B_3 PROJECT: Rutherfordton-Spindale Middle School PROJECT NO.: 2017010 CLIENT: LS3P for Rutherford County Schools PROJECT LOCATION: Rutherfordton, North Carolina LOCATION: Proposed Building Pad ELEVATION: 1050ft-MSL+/ DRILLER: FST LOGGED BY: A.Kuczero DRILLING METHOD: Diedrich D-50 HSA DATE: 4/5/2017 DEPTH TO - WATER> INITIAL: s DRY AFTER 24 HOURS: = DRY CAVING> -L 42.0' c O J w Description U �_ O 2 N T z Graphic Depiction • BLOW . NATURAL PLASTIC 10 COUNT MOISTURE LIMIT 20 LIQUID 60 LIMIT 10 101 100 100c, 995 990 985 980 Moist, medium dense, tan and brown, micaceous, siltyfine to medium SAND (SM) Moist, loose to medium dense, brown, highly micaceous, silty fine SAND SM I 3-5-7 4-6-6 4-6-10 30 40 12 40 12 45 16 50 Boring Terminated at 50.0 feet 00 55 60 65 70 Page 2 of 2 N OVA TEST BORING RECORD B-4 c O J >� 0 104! 5 104( 10 103 PROJECT: Rutherfordton-Spindale Middle School PROJECT NO.: 2017010 CLIENT: LS3P for Rutherford County Schools PROJECT LOCATION: Rutherfordton, North Carolina LOCATION: Proposed Building Pad ELEVATION: 1048 ft-MSL +/ DRILLER: FST LOGGED BY: A.Kuczero DRILLING METHOD: Diedrich D-50 HSA DATE: 4/5/2017 DEPTH TO - WATER> INITIAL: s DRY AFTER 24 HOURS: s DRY CAVING> -L N/A Graphic Depiction Description �_ E T BLOW COUNT P ' � o NATURAL MOISTURE PLASTIC LIMIT ILIQUID LIMIT 10 20 30 40 60 10 Topsoil (4 inches) i _ RESIDUUM: Moist, stiff, reddish brown, micaceous, clayey ELASTIC SILT (MH) with some fine sand Moist, firm, red and brown, highly micaceous, fine sandy SILT (ML) Moist, loose, orange and brown, micaceous, siltyfine to medium SAND (SM) _ r 103 1 Moist, firm, red and brown, highly micaceous, fine sandy SILT (ML) Boring Terminated at 20.0 feet 102 102 101 3-5-6 4-6-9 9 4-4-5 , 8 3-4-4 0 7 3-3-4 0 3-4-5 E 15 N OVA TEST BORING RECORD B-5 5 104( 10 103 15 103 20 102 25 102 30 101 35 101 PROJECT: Rutherfordton-Spindale Middle School PROJECT NO.: 2017010 CLIENT: LS3P for Rutherford County Schools PROJECT LOCATION: Rutherfordton, North Carolina LOCATION: Proposed Building Pad ELEVATION: 1045 ft-MSL +/ DRILLER: FST LOGGED BY: A.Kuczero DRILLING METHOD: Diedrich D-50 HSA DATE: 4/5/2017 DEPTH TO - WATER> INITIAL: s DRY AFTER 24 HOURS: s DRY CAVING> -L N/A Graphic Depiction Description �_ E T BLOW COUNT P ' � o NATURAL MOISTURE PLASTIC LIMIT ILIQUID LIMIT 10 20 30 40 60 10 Topsoil (4 inches) RESIDUUM: Moist, stiff, reddish brown, micaceous, clayey ELASTIC SILT (MH) with some fine sand Moist, stiff, reddish brown, micaceous, clayey SILT (ML) with some fine sand ------------------------ Moist, stiff, orange and brown, micaceous, fine sandy SILT (M L) Boring Terminated at 20.0 feet 3-5-7 12 16 4-7-9 0 14 5-7-7 9 3-4-5 4 8 3-4-4 9 4-4-5 4 APPENDIX C Laboratory Data 60 50 X 40 w 0 z !z: 30 0 H Q J a 20 10 0 0 92 90 88 86 z w 84 z 0 82 w Q 80 78 76 74 LIQUID AND PLASTIC LIMITS TEST REPORT Dashed line indicates the approximate upper limit boundary for natural soils GX\ of O� • Off' G`-ot ML or OL mmhMH or OH l U zu 3u 4o bU 6U /U Wuu UU 1 UU "I l U LIQUID LIMIT NUMBER OF BLOWS MATERIAL DESCRIPTION LL PL Moist, stiff, reddish brown, micaceous, clayey ELASTIC SILT 81 39 (MI) with some fine sand Project No. 2017010 Client: LS31? for Rutherford County Schools Project: Rutherfordton-Spindale Middle School Source of Sample: B-1 Depth: 1.0 Nova Engineering & Environmental Charlotte NC Tested By: AK Checked By: DP PI %<#40 %<#200 USCS 42 84.2 MIT Remarks: *Natural Moisture: 34.3% 60 50 X 40 w 0 z !z: 30 0 H Q J a 20 10 0 0 53 52 51 50 z w 49 z 0 48 w Q 47 46 45 44 LIQUID AND PLASTIC LIMITS TEST REPORT Dashed line indicates the approximate upper limit boundary for natural soils Off' GX\ of O� G`-ot ML or OL mmhMH or OH l U zu 3u 4o bU 6U /U Wuu UU 1 UU "I l U LIQUID LIMIT NUMBER OF BLOWS MATERIAL DESCRIPTION LL PL Moist, firm, orange and brown, highly micaceous, fine sandy 46 40 SILT (ML) Project No. 2017010 Client: LS31? for Rutherford County Schools Project: Rutherfordton-Spindale Middle School Source of Sample: B-2 Depth: 6.0 Nova Engineering & Environmental Charlotte NC Tested By: AK Checked By: DP PI %<#40 %<#200 USCS 6 64.3 ML Remarks: Natural Moisture: 27.5% 60 50 X 40 w 0 z !z: 30 0 H Q J a 20 10 0 0 87 86 85 84 z w 83 z 0 82 w Q 81 80 79 78 LIQUID AND PLASTIC LIMITS TEST REPORT Dashed line indicates the approximate upper limit boundary for natural soils GX\ of O� • Off' G`-ot ML or OL mmhMH or OH l U zu 3u 4o bU 6U /U Wuu UU 1 UU "I l U LIQUID LIMIT NUMBER OF BLOWS MATERIAL DESCRIPTION LL PL Moist, stiff, reddish brown, micaceous, clayey ELASTIC SILT 83 41 (MI) with some fine sand Project No. 2017010 Client: LS31? for Rutherford County Schools Project: Rutherfordton-Spindale Middle School Source of Sample: B-4 Depth: 1.0 Nova Engineering & Environmental Charlotte NC Tested By: AK Checked By: DP PI %<#40 %<#200 USCS 42 80.5 MIT Remarks: *Natural Moisture: 36.4% 60 50 X 40 w 0 z !z: 30 0 H Q J a 20 10 0 0 90 88 86 84 z w 82 z Oo 80 w Q 78 76 74 72 LIQUID AND PLASTIC LIMITS TEST REPORT Dashed line indicates the approximate upper limit boundary for natural soils GX\ of O� • Off' G`-ot ML or OL mmhMH or OH l U zu 3u 4o bU 6U /U Wuu UU 1 UU "I l U LIQUID LIMIT NUMBER OF BLOWS MATERIAL DESCRIPTION LL PL Moist, stiff, reddish brown, micaceous, clayey ELASTIC SILT 79 41 (MI) with some fine sand Project No. 2017010 Client: LS31? for Rutherford County Schools Project: Rutherfordton-Spindale Middle School Source of Sample: B-5 Depth: 1.0 Nova Engineering & Environmental Charlotte NC Tested By: AK Checked By: DP PI %<#40 %<#200 USCS 38 82.1 MIT Remarks: *Natural Moisture: 34.0% APPENDIX D Qualifications of Recommendations Ifts QUALIFICATIONS OF RECOMMENDATIONS The findings, conclusions and recommendations presented in this report represent our professional opinions concerning subsurface conditions at the site. The opinions presented are relative to the dates of our site work and should not be relied on to represent conditions at later dates or at locations not explored. The opinions included herein are based on information provided to us, the data obtained at specific locations during the study and our past experience. If additional information becomes available that might impact our geotechnical opinions, it will be necessary for NOVA to review the information, reassess the potential concerns, and re-evaluate our conclusions and recommendations. Regardless of the thoroughness of a geotechnical exploration, there is the possibility that conditions between borings will differ from those encountered at specific boring locations, that conditions are not as anticipated by the designers and/or the contractors, or that either natural events or the construction process have altered the subsurface conditions. These variations are an inherent risk associated with subsurface conditions in this region and the approximate methods used to obtain the data. These variations may not be apparent until construction. The professional opinions presented in this geotechnical report are not final. Field observations and foundation installation monitoring by the geotechnical engineer, as well as soil density testing and other quality assurance functions associated with site earthwork and foundation construction, are an extension of this report. Therefore, NOVA should be retained by the owner to observe all earthwork and foundation construction to document that the conditions anticipated in this study actually exist, and to finalize or amend our conclusions and recommendations. NOVA is not responsible or liable for the conclusions and recommendations presented in this report if NOVA does not perform these observation and testing services. This report is intended for the sole use of CLIENT only. The scope of work performed during this study was developed for purposes specifically intended by CLIENT and may not satisfy other users' requirements. Use of this report or the findings, conclusions or recommendations by others will be at the sole risk of the user. NOVA is not responsible or liable for the interpretation by others of the data in this report, nor their conclusions, recommendations or opinions. Our professional services have been performed, our findings obtained, our conclusions derived and our recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices in the State of North Carolina. This warranty is in lieu of all other statements or warranties, either expressed or implied. Geotechnical-Engineering Report Geotechnical Services Are Performed for Specific Purposes, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical-engineering study conducted for a civil engineer may not fulfill the needs of a constructor — a construction contractor — or even another civil engineer. Because each geotechnical- engineering study is unique, each geotechnical-engineering report is unique, prepared solely for the client. No one except you should rely on this geotechnical-engineering report without first conferring with the geotechnical engineer who prepared it. And no one — not even you — should apply this report for any purpose or project except the one originally contemplated. Read the Full Report Serious problems have occurred because those relying on a geotechnical-engineering report did not read it all. Do not rely on an executive summary. Do not readselected elements only. Agftk assessment of their impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed. Subsurface Conditions Can Change A geotechnical-engineering report is based on conditions that existed at the time the geotechnical engineer performed the study. Do not rely on a geotechnical-engineering report whose adequacy may have been affected by: the passage of time; man-made events, such as construction on or adjacent to the site; or natural events, such as floods, droughts, earthquakes, or groundwater fluctuations. Contact the geotechnical engineer before applying this report to determine if it is still reliable. A ,fhb A�morount of additional testing or analysis could prevent oblems. Geotechnical Engineers Base Each Report on a Unique Set of Project -Specific Factors Geotechnical engineers consider many unique, project -specific factors when establishing the scope of a study. Typical factors include: the client's goals, objectives, and risk -management preferences; the general nature of the structure involved, its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specifically indicates otherwise, do not rely on a geotechnical-engineering report that was: • not prepared for you; • not prepared for your project; • not prepared for the specific site explored; or • completed before important project changes were made. Typical changes that can erode the reliability of an existing geotechnical-engineering report include those that affect: • the function of the proposed structure, as when it's changed from a parking garage to an office building, or from a light - industrial plant to a refrigerated warehouse; • the elevation, configuration, location, orientation, or weight of the proposed structure; • the composition of the design team; or • project ownership. As a general rule, always inform your geotechnical engineer of project changes —even minor ones —and request an Most Geotechnical Findings Are Professional Opinions Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. Geotechnical engineers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ — sometimes significantly — from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide geotechnical-construction observation is the most effective method of managing the risks associated with unanticipated conditions. A Report's Recommendations Are Not Final Do not overrely on the confirmation -dependent recommendations included in your report. Confirmation - dependent recommendations are not final, because geotechnical engineers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual subsurface conditions revealed during construction. The geotechnical engineer who developed your report cannot assume responsibility or liability for the report's confirmation -dependent recommendations if that engineer does not perform the geotechnical-construction observation required to confirm the recommendations' applicability. A Geotechnical-Engineering Report Is Subject to Misinterpretation Other design -team members' misinterpretation of geotechnical-engineering reports has resulted in costly problems. Confront that risk by having your geotechnical engineer confer with appropriate members of the design team after submitting the report. Also retain your geotechnical engineer to review pertinent elements of the design team's plans and specifications. Constructors can also misinterpret a geotechnical-engineering report. Confront that risk by having your geotechnical engineer participate in prebid and preconstruction conferences, and by providing geotechnical construction observation. Do Not Redraw the Engineer's Logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical-engineering report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk. Obtain Professional Assistance To Deal Give Constructors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make constructors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give constructors the complete geotechnical-engineering report, but preface it with a clearly written letter of transmittal. In that letter, advise constructors that the report was not prepared for purposes of bid development and that the report's accuracy is limit encourage them to confer with the geotechnical engineer who prepared the report (a modest fee maybe required) and/ or to conduct additional study to obtain the specific types of information they need or prefer. A prebid conference can also be valuable. Be sure constructors have sufficient time to perform additional study. Only then might you be in a position to give constructors the best information available to you, while requiring them to at least share some of the financial responsibilities stemming fro icipated conditions. others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly. Environmental Concerns Are Not Covered The equipment, techniques, and personnel used to perform an environmental study differ significantly from those used to perform a geotechnical study. For that reason, a geotechnical- engineering report does not usually relate any environmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated environmental problems have led to numerous project failures. If you have not yet obtained your own environmental information, ask your geotechnical consultant for risk -management guidance. Do not rely on an report prepared for someone else. with Mold Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant amounts of mold from growing on indoor surfaces. To be effective, all such strategies should be devised for the express purpose of mold prevention, integrated into a comprehensive plan, and executed with diligent oversight by a professional mold -prevention consultant. Because just a small amount of water or moisture can lead to the development of severe mold infestations, many mold- prevention strategies focus on keeping building surfaces dry. While groundwater, water infiltration, and similar issues may have been addressed as part of the geotechnical- engineering study whose findings are conveyed in this report, the geotechnical engineer in charge of this project is not a mold prevention consultant; none of the services performed in connection with the geotechnical engineer's study were designed or conducted for Ir the purpose of mold prevention. Proper implementation of the recommendations conveyed in this report will not of itself be su ficient to prevent mold from growing in or on the structure Read Responsibility Provisions Closely Some clients, design professionals, and constructors fail to recognize that geotechnical engineering is far less exact than other engineering disciplines. This lack of understanding has created unrealistic expectations that have led to disappointments, claims, and disputes. To help reduce the risk of such outcomes, geotechnical engineers commonly include a variety of explanatory provisions in their reports. Sometimes labeled "limitations; many of these provisions indicate where geotechnical engineers' responsibilities begin and end, to help involved. Rely, on Your GBC-Member Geotechnical Engineer for Additional Assistance Membership in the Geotechnical Business Council of the Geoprofessional Business Association exposes geotechnical engineers to a wide array of risk -confrontation techniques that can be of genuine benefit for everyone involved with a construction project. Confer with you GBC-Member geotechnical engineer for more information. GErmGEOTECHNICAL BUSINESS COUNCIL 41 411�oftheGeopwfessiannlBmin—A..s cation 8811 Colesville Road/Suite G106, Silver Spring, MD 20910 Telephone:301/565-2733 Facsimile:301/589-2017 e-mail: info@geoprofessional.org www.geoprofessional.org Copyright 2015 by Geoprofessional Business Association (GBA). Duplication, reproduction, or copying of this document, or its contents, in whole or in part, by any means whatsoever, is strictly prohibited, except with GBA's specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of GBA, and only for purposes of scholarly research or book review. Only members of GBA may use this document as a complement to or as an element of a geotechnical-engineering report. Any other firm, individual, or other entity that so uses this document without being a GBA member could be commifing negligent or intentional (fraudulent) misrepresentation.