REVISED REPORT OF GEOTECHNICAL EXPLORATION. Proposed Dollar Tree East 17 th Street and Old Greenbrier Road Springfield, Tennessee.

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1 REVISED REPORT OF GEOTECHNICAL EXPLORATION Proposed Dollar Tree East 17 th Street and Old Greenbrier Road Springfield, Tennessee Prepared for: Mr. K. Scott Brown Clark, Geer, Latham & Associates, Inc. 391 Springhill Avenue Mobile, Alabama 3668 Prepared by: Professional Service Industries, Inc. 751 South 5 th Street Nashville, Tennessee 3726 (615) January 14, 214 PSI Project No Revision 1

2 January 14, 214 Clark, Geer, Latham & Associates, Inc. 391 Springhill Avenue Mobile, Alabama 3668 Attention: Subject: Mr. K. Scott Brown Revised Report of Geotechnical Exploration Proposed Dollar Tree East 17 th Street and Old Greenbrier Road Springfield, Tennessee PSI Project No Revision 1 Dear Mr. Brown: Professional Service Industries, Inc. is pleased to transmit our Revised Report of Geotechnical Exploration for the Proposed Dollar Tree Store in Springfield, Tennessee. This report includes the results of field and laboratory testing, and recommendations for foundation and pavement design, as well as general site development. We appreciate the opportunity to perform this Geotechnical Exploration and look forward to continued participation during the design and construction phases of this project. If you have any questions pertaining to this report, or if we may be of further service, please contact our office. Respectfully Submitted, PROFESSIONAL SERVICE INDUSTRIES, INC. S. Wayne Gibbs, P.E. Wayne F. Harnack, P.E. Geotechnical Department Manager Senior Vice President Reviewed by: Lloyd Lasher Principal Consultant Professional Service Industries, Inc. 751 South 5 th Street, Nashville, Tennessee Phone Fax

3 TABLE OF CONTENTS 1 PROJECT INFORMATION PROJECT AUTHORIZATION PROJECT DESCRIPTION PURPOSE & SCOPE OF SERVICES SITE & SUBSURFACE CONDITIONS SITE LOCATION & DESCRIPTION SITE GEOLOGY EXPLORATION PROCEDURES SUBSURFACE CONDITIONS GROUNDWATER INFORMATION EVALUATION & RECOMMENDATIONS GEOTECHNICAL DISCUSSION SITE PREPARATION FOUNDATION RECOMMENDATIONS FLOOR SLAB RECOMMENDATIONS GEOLOGIC HAZARDS GENERAL PAVEMENT RECOMMENDATIONS SEISMIC DESIGN CONSIDERATIONS CONSTRUCTION CONSIDERATIONS MOISTURE SENSITIVE SOILS & WEATHER RELATED CONCERNS DRAINAGE & GROUNDWATER CONCERNS EXCAVATIONS REPORT LIMITATIONS TABLES TABLE 1 Approximate Depths and Elevations of Fill Materials and Boring Termination TABLE 2 Recommended Pavement Thicknesses TABLE 3 Seismic Design Values LIST OF APPENDICES APPENDIX A BORING LOCATION PLAN APPENDIX B GENERAL NOTES & BORING LOGS APPENDIX C LABORATORY TEST RESULTS

4 1.1 PROJECT AUTHORIZATION 1 PROJECT INFORMATION Professional Service Industries, Inc. (PSI) has completed a geotechnical exploration for the proposed Dollar Tree in Springfield, Tennessee. Our services were authorized by Mr. K. Scott Bowman of Clark, Geer, Latham & Associates, Inc. on December 2, 213 by signing our proposal. 1.2 PROJECT DESCRIPTION Project information was provided by Mr. Scott Brown of Clark, Geer, Latham and Associates, Inc. in s dated December 17, 213 and January 1, 214. The provided information included an undated site layout plan as well as a drawing titled Grading and Drainage, dated January 7, 214, as prepared by Littlejohn Engineering Associates. A Report of Geotechnical Exploration, dated January 13, 214, of our findings and recommendations was released to the client. However, during discussions between Messrs. Wayne Gibbs of PSI and Scott Brown, we revised our recommendations for undercutting within the building footprint to be based on current site grades. The site is currently a vacant, grassed lot to the northeast of the intersection between East 17 th Avenue and Old Greenbrier Road. An existing ditch crossed the western portion of the site in a north-south direction. The site appeared to slope to the west with approximately 5 feet of total relief. Based on the provided information and our understanding of the project, we anticipate the proposed construction will be as follows: Single story structure 1, Square Feet of Ground Cover Maximum assumed column loads of less than 75 Kips Maximum assumed continuous wall loads of less than 4 KLF Grade Supported Floor Slab Minimal grade changes with cut/fills of less than 5 feet Asphalt Pavement Parking and Drives Elevations have been interpolated based on the provided drawings and should be considered approximate. The geotechnical recommendations presented in this report are based on the available project information, building location, and the subsurface materials described in this report. If any of the noted information is incorrect, please inform PSI in writing so that we may amend the recommendations presented in this report if appropriate and if desired by the client. PSI will not be responsible for the implementation of its recommendations when it is not notified of changes in the project. 1

5 1.3 PURPOSE & SCOPE OF SERVICES The purpose of this study was to explore the subsurface conditions and develop conclusions and recommendations for design and construction of the foundation and general pavement systems for the proposed project. Our scope of services included drilling six (6) soil test borings at the site to depths of approximately 1 feet to 2 feet. Our scope also included select laboratory testing and preparation of this geotechnical report. This report outlines the testing procedures, presents available project information, describes the site and subsurface conditions, and presents recommendations regarding the following: General site preparation. Foundation types, depths and allowable bearing capacities. General pavement design criteria and pavement subgrade preparation. Comments regarding observed factors that may impact construction and/or structure/pavement performance. The scope of services did not include an environmental assessment for determining the presence or absence of wetlands, or hazardous or toxic materials in the soil, bedrock, surface water, groundwater, or air, on, or below, or around this site. Any statement in this report or on the boring logs regarding odors, colors, and unusual or suspicious items or conditions are strictly for informational purposes. Prior to further development of this site, an environmental assessment is advisable. 2

6 2 SITE & SUBSURFACE CONDITIONS 2.1 SITE LOCATION & DESCRIPTION The site for the proposed Dollar Tree is located northeast of the intersection of East 17 th Avenue and Old Greenbrier Road in Springfield, Tennessee. The site is bordered by Old Greenbrier Road to the south, East 17 th Avenue to the west, and undeveloped property to the north and east. At the time of our field activities, the site was generally sloping downward from east to west with relief of approximately 5 feet across the site. In addition, a drainage ditch was observed in the center of the site that headed in a northerly/southerly direction. The ground cover primarily consisted of grass which had recently been cut at the time of our field activities. The surficial soils were firm, with the exception of those along the drainage ditch, at the time of the field exploration. 2.2 SITE GEOLOGY A review of the Greenbrier Geologic Quadrangle Map (1976) indicates this site is underlain by the Upper Mississippian Aged St. Louis Limestone Formation. This formation is typically a light olive to dark gray, very fine to medium-grained, medium to thick-bedded, fossiliferous limestone containing numerous chert stringers and nodules. Soil formed by the solution weathering of this parent limestone formation normally consists of reddish brown silty clay of low to moderate plasticity with occasional zones of high plasticity. Often bands of partially and unweathered chert exist within the overburden soil. The soil/bedrock interface is irregular with soil slots extending into the bedrock unit and more resistant pinnacles protruding into the soil zone. The formation is susceptible to solution weathering and sinkhole development. During our review of the Greenbrier Geologic Quadrangle Map, we also noted a closed depression within approximate ¼-mile of the subject property to the southeast. Based on review of aerial images and our site observations, the area appears to have been developed for commercial/industrial uses sometime before EXPLORATION PROCEDURES The site subsurface conditions were explored with six (6) soil test borings, four drilled in the proposed building vicinity and two drilled in parking and drive areas. The borings were located in the field by PSI personnel measuring distances from known site reference points using taping methods and should be considered approximate. Boring locations were adjusted based on access and to avoid existing utilities and structures. 3

7 The borings were advanced utilizing 3 ¼ inch diameter hollow stem augers and soil samples were routinely obtained during the drilling process. Representative soil samples were secured by means of conventional split-barrel sampling procedures in general accordance with ASTM D In this procedure, a 2-inch O.D., split-barrel sampler is driven into the soil a distance of 18 inches by a 14-pound hammer falling 3 inches. The number of blows required to drive the sampler through the final 12-inch interval, after initial seating of 6 inches, is termed the Standard Penetration Test (SPT) value or N-value, and is indicated for each sample on the boring logs in the Appendix. The SPT values can be used as a qualitative indication of the in-place relative density of cohesionless soils, and as a relative indication of consistency in cohesive soils. This indication is qualitative, since many factors can significantly affect the standard penetration resistance value and prevent a direct correlation between drill crews, drill rigs, drilling procedures, and hammer-rod-sampler assemblies. Each soil sample was classified on the basis of texture and plasticity in general accordance with the Unified Soil Classification System (ASTM D 2487). The various soil types were grouped into the major zones noted on the boring logs. After classification, representative soil samples were selected and tested in our laboratory to determine pertinent index and engineering properties and to check visual classifications. The laboratory testing program was conducted in general accordance with ASTM methods and included visual soil classifications (ASTM D 2487), washed sieve testing (ASTM D 114), natural moisture content determinations (ASTM D 2216), and Atterberg Limits testing (ASTM D 4318). 2.4 SUBSURFACE CONDITIONS The subsurface conditions identified by the 6 borings primarily included a stratum of topsoil between 7 inches and 16 inches thick, with the exception of boring B-4 which encountered an approximately 6 inch thick layer of gravel. Beneath the surficial layers of borings B-3 and B-4, possible fill materials were typically observed to an approximate depth of 3 feet below the current ground surface. The fill materials typically consisted of reddish low plasticity (lean) clays and some topsoil/gravel mixtures. Standard Penetration Test (SPT) N-values within these materials typically ranged from 2 blows per foot (BPF) to 7 BPF, indicating very soft to firm consistencies. Moisture contents within the fill materials were typically around 25 percent. Underlying the possible fill and surficial layers, residual soils were encountered. These residual soils were typically gray to reddish to dark yellow brown to grayish brown low plasticity to high plasticity (fat) clays which contained varying amounts of roots, silt, and chert. SPT N-values within the residual soils typically ranged between 3 BPF to 21 BPF, which indicated soft to very stiff consistencies. We note that very soft zones of residual materials were encountered in borings B-2, B-3, and P-2 at depths ranging from 1 ½-feet to 6 feet below the current ground surface. Moisture contents within the residual soils varied between 18 percent and 37 percent. 4

8 The following table summarizes the estimated fill depths and elevations at each of the boring locations relative to current surface elevation. We note that the elevations were based on the provided drawings and should be considered approximate. Boring Number Approximate Boring Surface Elevation (ft. MSL) Possible Fill Depth (ft) Depth (ft) (ft MSL) Boring Termination Depth (ft) (ft MSL) B NE NE B NE NE B B P NE NE P NE NE Table 1 Approximate Depth and Elevations of Fill Materials and Boring Termination NE Not Encountered Washed sieve analysis of selected samples resulted in 79% and 94% passing the #2 sieve, indicating a fine-grained material. Atterberg limits testing on select samples of residual materials in borings B-2 and B-4 indicated liquid limits of 32 and 33, respectively, with plasticity indices of 16. According to the United Soils Classification System, the soils classified as a Lean Clay CL. Materials visually classified as High Plasticity Clay CH were also identified during our review of the soil samples. The above description is of a generalized nature to highlight the major subsurface stratification features and material characteristics. The boring logs included in the appendix should be reviewed for specific information at individual boring locations. These records include soil/rock descriptions, stratifications, penetration resistances, locations of the samples and laboratory test data. The stratification shown on the boring logs represent the conditions only at the actual boring locations. Variations may occur and should be expected between boring locations. The stratification represents the approximate boundary between subsurface materials and the actual transition may be gradual. Water level information obtained during field operations is also shown on the boring logs. The samples that were not altered by laboratory testing will be retained for 6 days from the date of this report and then will be discarded. 5

9 2.5 GROUNDWATER INFORMATION Apparent groundwater was encountered during drilling activities in 3 of the borings (B-2, B-3, and P-2) and varied in depth between 1 foot and 5 ½ feet below the current ground surface elevation. We note that prior to our field activities, the area had recently experienced rain and snow events and the ground surface around the drainage ditch was visibly saturated. Discontinuous zones of perched water may also exist within the overburden materials and/or at the contact with bedrock. The groundwater information presented in this report is the information that was collected at the time of our field activities. We recommend that the Contractor determine the actual groundwater level at the site at the time of the construction activities. 6

10 3 EVALUATION & RECOMMENDATIONS 3.1 GEOTECHNICAL DISCUSSION Approximately 3 feet of possible fill materials as well as approximately 6 feet of very soft to soft residual soils were encountered at the site during our field activities. If left in place, these materials could adversely affect structure and pavement performance. Additionally, apparent groundwater was encountered in three of the borings at depths between 1 foot and 5 ½ feet below the current ground surface elevation. During discussions with the client regarding the subsurface conditions encountered, the client informed PSI they wish to proceed with undercut and replacement for the foundation and subgrade to improve the site. The client should understand that dewatering will likely be required to complete the site grading and the client should budget for and allow schedule days for water removal and subgrade drying; especially if site preparation activities are planned during traditionally wetter months or periods of prolonged rainfall. Due to the shallow presence of apparent groundwater and depth of unsuitable materials, we recommend that shotrock fill materials be utilized as backfill in place of typical soil fill. Based on the field exploration and our understanding of final grades, we anticipate that approximately 6 feet of unsuitable material from the current ground surface elevation will need to be removed in order to support the building foundations on a minimum of 3 feet of suitable shotrock fill materials. In the proposed pavement areas, we anticipate that a minimum undercut of 3 feet from the current ground surface elevation and backfilled with shotrock fill materials will be suitable. Information pertaining to the age, placement, and compaction of the fill has not been provided. As is the case with any fill placed without technical observations, the possibility exists that the fill may contain concentrated amounts of deleterious material and soft compressible zones not disclosed by our borings and the associated risk of excessive and/or non-uniform settlement caused by extensive zones or pockets of soft, loose, or uncompacted material. We note that we have not received information regarding fill placement and therefore we consider this material to be undocumented. If the client can locate records of fill placement and quality control, we request copies be forwarded to PSI for review. Upon review of such documentation, PSI may be able to determine if the fill materials placed may be suitable for support of the building foundations and parking areas. Due to the very soft consistency of the underlying soils and the potential for unsuitable materials on this site, the client may elect to utilize a biaxial or triaxial geogrid or geo-fabric in conjunction with the selected undercut and backfill to further support the building and pavement structures. We recommend that the client confer with the manufacturer of the geogrid or fabric for the most suitable design and implementation of their chosen material. 7

11 A closed depression was noted on the Greenbrier Geologic Quadrangle map during our review of the local geology within a ¼-mile of the site to the southeast. While we did not observe surficial evidence of sinkhole or solution activity, this area and geology is known to be susceptible to sinkhole formations. We strongly encourage the client to confer with the design team and a contractor with regard to the recommendations contained in this report, in an effort to assess potential costs and schedule for implementing the anticipated course of action. 3.2 SITE PREPARATION We recommend that topsoil, vegetation, roots, and surficial materials be stripped from the site and either wasted or stockpiled for later use in landscaping (subject to the approval of the landscape architect). In addition, it is not unusual to find zones or pockets of construction debris that may have been buried on the site. Construction debris or deleterious materials encountered during site preparation and construction should be removed. Following stripping, previously placed fill, highly plastic materials and soft soils should be undercut and removed. The area of undercut should extend a minimum distance of 1 feet beyond the building perimeter. The exposed subgrade within the building and parking areas should then be proof-rolled with a loaded tandem axle dump truck or similar rubber tired vehicle. Soils that are observed to rut or deflect excessively under the moving load should be further undercut and replaced with properly compacted fill. The proof-rolling and undercutting activities should be observed by a representative of the geotechnical engineer and should be accomplished during a period of dry weather. Following satisfactory completion of the proof-roll, fill placement may begin. Due to the potential shallow groundwater table that may be present on this project site, we recommend that either durable shotrock or stone fill be utilized as Engineered Fill. For shotrock fill material placed in the top 2 feet of finished grade, the maximum particle size should be 8 inches. Shotrock fill should have adequate fines to effectively "choke" the larger rock pieces, filling all voids or open spaces. The percentage of soil in the shotrock fill should be limited to a maximum of 1 percent. In addition, the client may elect to utilize a biaxial or triaxial geogrid in their design. These types of materials are typically designed by the manufacturer based on the project s requirements and specifications. 8

12 3.3 FOUNDATION RECOMMENDATIONS Following site preparation as previously recommended, it is our opinion the proposed building may be supported by conventional spread footings underlain by durable shotrock fill placed in accordance with the depths and recommendations of this report. For shotrock fill placed a minimum thickness of at least 3 feet below the proposed bottom of footing elevation, the shallow foundations can be designed for an allowable bearing pressure of 4, psf. The recommended allowable soil bearing capacities can be increased by ⅓ for short term wind and/or seismic loads. Minimum widths of 24 inches for column footings and 18 inches for continuous footings should be used in foundation design to minimize the possibility of a local bearing capacity failure. Footings should be located at a depth of at least 18 inches below the final exterior grade to provide adequate frost protection. If geogrid is utilized, we recommend that the material be placed a minimum of 1 feet beyond the exterior of the building foundations. The placement of the geogrid will also require that utility excavations and installation be coordinated so that the geogrid does not conflict or require cutting and removal for their placement. The client and contractor should review utility locations prior to placement of geogrid. We recommend that a minimum of 18 inches of shotrock fill be placed to provide an initial bearing surface prior to additional shotrock or geogrid placement. The placement and design of the geogrid system should be reviewed by the manufacturer per their specifications. Upon placement of the initial lift, the subgrade should be proof-rolled prior to geogrid installation. Additional shotrock lifts may be necessary if the subgrade is still soft. The foundation excavations should be observed by a representative of PSI prior to steel or concrete placement to assess that the foundation materials are capable of supporting the design loads and are consistent with the materials described in this report. Soft or loose soil zones encountered at the bottom of the footing excavations should be removed to the level of approved soils or adequately compacted fill as directed by the geotechnical engineer. Cavities formed as a result of excavation of soft or loose soil zones should be backfilled with lean concrete or dense graded compacted crushed stone, as determined by the geotechnical engineer. After opening, footing excavations should be observed and concrete placed as quickly as possible to avoid exposure of the footing bottoms to wetting and drying. Surface run-off water should be drained away from the excavations and not be allowed to pond. The foundation concrete should be placed the same day the excavation is made. If it is required that footing excavations be left open for more than 1 day, they should be protected to reduce evaporation or entry of moisture. 9

13 Based on the known subsurface conditions and site geology, laboratory testing, and past experience, we anticipate that properly designed and constructed footings supported on the recommended shotrock materials should experience maximum total and differential settlements within tolerable limits for conventional construction types. As an alternate to undercut and replacement, the client may elect to utilize an intermediate foundation system such as aggregate piers or helical anchors for support of the building foundation. Should the client wish to pursue this design, PSI can provide additional recommendations and references for specialty contractors familiar with this type of foundation system. 3.4 FLOOR SLAB RECOMMENDATIONS The floor slab can be grade supported on suitable shotrock fill following the site preparation activities outlined in this report. Proof-rolling, as discussed earlier in this report, should be accomplished to identify any soft or unstable soils, which should be removed from the floor slab area prior to fill placement and/or floor slab construction. Any high plasticity soil (PI>5) or soft soils present within 3 feet of the slab subgrade should be removed and replaced with a properly compacted fill. We recommend that a minimum 4-inch thick granular mat be placed beneath the floor slab to enhance drainage and provide a capillary break. In areas with moisture sensitive floor finishes or if required by code or the floor manufacturer, polyethylene sheeting should be placed to act as a vapor retarder. This retarder should be at least 1 mil in thickness and used in accordance with current ACI standards as in 32.2R-6. Where vapor retarders are used, the contractor must follow appropriate slab finishing and curing methods to reduce the risk of slab curling. The floor slabs should have an adequate number of joints to reduce cracking resulting from any differential movement and shrinkage. The floor slab should not be rigidly connected to columns, walls, or foundations. Given the relatively high water table encountered, the client may consider an underslab drainage system to reduce the potential of adverse effects to the slab from a fluctuating water table. 3.5 GEOLOGIC HAZARDS Because the site is underlain by carbonate rock, there is some risk of sinkhole development within the subject property. This area has been identified as having a high density of karst features with caves, sinkholes, and disappearing streams by the 1977 Geologic Hazards Map of Tennessee, by Robert A. Miller. Additionally, the Greenbrier Geologic Quadrangle Map indicated a closed depression located within a ¼ mile of the subject site. 1

14 We did not observe surface evidence of sinkholes or solution activity in the building area during our site reconnaissance and our borings did not indicate definitive solution activity. A specific exploration to determine the extent of sinkhole development or solution activity on this site and the influence it may have on the proposed project was not included in the scope of work for this project. The present standard of practice of geotechnical engineering does not permit accurate prediction of where or when sinkholes will occur. The owner may wish to consider additional geophysical testing, such as electrical resistivity, to better assess the risk of sinkhole development or solution activity on this site. Based on our local knowledge and review of available information, we believe this site has a MODERATE risk of sinkhole development. Site grading should be established to provide positive drainage both during and after construction so as to minimize the potential for future sinkhole development. During construction, the grading and general contractor should be alert to any indication of possible sinkhole activity. Any sinkholes or solution activity encountered during the site grading or construction should be repaired under the direction of the geotechnical engineer. 3.6 GENERAL PAVEMENT RECOMMENDATIONS Following site preparation as previously recommended, the pavements can be grade supported on suitable shotrock fill materials. As an alternative and if the client is willing to accept the risk of increased maintenance and pavement distress, the depth of undercut for the parking areas may be reduced should a biaxial or triaxial geogrid be utilized to help support the pavement section. Should the client accept the increased risk, we recommend removal of the soft, unsuitable soils in the parking areas a minimum depth of approximately 3 feet from the current surface elevation and backfilling the undercut areas with suitable shotrock fill in conjunction with the placement of at least one layer of a biaxial or triaxial geogrid. Upon backfilling the undercut areas, properly compacted Engineered Fill may be utilized to bring the parking areas to subgrade elevation for support of the pavements. Proof-rolling, as discussed earlier in this report, should be accomplished for either option to identify any soft or unstable soils, which should be removed from the pavement area prior to fill placement and/or pavement construction. These soils will likely pump and deflect during proof-rolling, and may need to be moisture conditioned or removed and replaced prior to placement of the Engineered Fill or the design pavement section. Our scope of services did not include extensive sampling and CBR testing of existing subgrade or potential sources of imported fill for the specific purpose of a detailed pavement analysis. Instead, we have assumed pavement-related design parameters that are considered to be typical for the area soil types. 11

15 We have estimated the subgrade soils will be prepared to achieve a minimum CBR of 3, assuming any unsuitable areas have been remediated. Making this assumption, it is possible to use typical pavement sections consisting of the following: Recommended Thickness (Inches) Pavement Materials Vehicle Parking Dumpster Pads / Truck Lanes Asphaltic Surface Course 1 ½ 2 Asphaltic Binder Course 2 3 Crushed Stone Base 6 8 Table 2 Recommended Pavement Structure Thicknesses Rigid concrete pavement consisting of 6 inches of concrete (f c=4 psi) underlain by 6 inches of basestone is recommended where trash dumpsters or areas subject to semitrailers or where a considerable load is transferred from relatively small steel wheels, such as truck dollies, and may be imposed on the pavement section. This should provide better distribution of surface loads to the subgrade without causing surficial deformation. The above sections represent minimum thicknesses representative of typical local construction practices and periodic maintenance should be anticipated. Pavement materials may be placed after the subgrade has been properly compacted, fine graded and proof-rolled as recommended in the site preparation section of this report. The activity should be accomplished in accordance with State Transportation Department guidelines. Actual pavement section thicknesses should be determined by the design civil engineer or geotechnical engineer based on traffic loads, volume, and the owners design life requirements. Water should not be allowed to pond behind curbs and saturate the pavement base stone. In down grade areas, base stone should extend through the slope to allow any water entering the basestone a path to exit. 3.7 SEISMIC DESIGN CONSIDERATIONS Seismic design considerations and recommendations are based on the 26 International Building code (IBC). The soil profile at the site consists of lean and fat clay fill and residual materials. A Site Class D designation is appropriate for the structure. According to the USGS interactive seismic mapping information ( the following design values would be appropriate for the project site. 12

16 Design Values Site Class D Spectral Response Accelerations Site Coefficients.2 sec S s.389 g 1. sec S g F a F v Design Spectral Response.2 sec S DS.386 g Accelerations 1. sec S D1.214 g Table 3 Seismic Design Values 13

17 4 CONSTRUCTION CONSIDERATIONS PSI should be retained to provide observation and testing of construction activities involved in the foundations, and pavements, earthwork, and related activities of this project. PSI cannot accept responsibility for any conditions, which deviated from those, described in this report, nor for the performance of the foundations and pavements if not engaged to also provide construction observation and testing for this project. 4.1 MOISTURE SENSITIVE SOILS & WEATHER RELATED CONCERNS The upper fine-grained soils encountered at this site will be sensitive to disturbances caused by construction traffic and changes in moisture content. During wet weather periods, increases in the moisture content of the soil can cause significant reduction in the soil strength and support capabilities. In addition, soils which become wet may be slow to dry and thus significantly retard the progress of grading and compaction activities. It will, therefore, be advantageous to perform earthwork and foundation construction activities during dry weather. 4.2 DRAINAGE & GROUNDWATER CONCERNS Water should not be allowed to collect in the foundation excavation, on floor slab areas, or on prepared subgrades of the construction area either during or after construction. Undercut or excavated areas should be sloped toward one corner to facilitate removal of any collected rainwater, groundwater, or surface runoff. Positive site surface drainage should be provided to reduce infiltration of surface water around the perimeter of the building and beneath the floor slabs. The grades should be sloped away from the building and surface drainage should be collected and discharged such that water is not permitted to infiltrate the backfill and floor slab areas of the building. Standing water was observed at the site and groundwater was measured at depths ranging from 1 foot to 5 ½ feet below the current ground surface elevation. We note that in this geology, it is not uncommon for discontinuous zones of perched water to exist within the overburden materials and/or at the contact with bedrock. Any water accumulation should be removed from excavations by pumping. We recommend that the Contractor determine the actual groundwater level at the site at the time of the construction activities. Based on the encountered depth of water, we anticipate that construction dewatering will be required. If seepage is encountered at shallow depths, it is anticipated that it can be controlled by simple means such as pumping from sumps or the use of perimeter trenches to collect and discharge the water away from the work area. We recommend all excavations where groundwater is encountered be observed on an individual basis to determine if interior drain systems are required. 14

18 4.3 EXCAVATIONS Auger refusal materials were not encountered during the subsurface exploration. Auger refusal conditions generally correspond to materials, which require blasting or heavy equipment for removal. Typically, soils penetrated by augers can be removed with conventional earthmoving equipment. However, excavation equipment varies, and field refusal conditions may vary. Neither refusal materials nor bedrock were detected above anticipated grade during our exploration. Based on the results of our exploration, we do not expect the need for blasting or difficult rock excavation methods for the planned construction. At this time, we have not been provided information regarding site grading or utility excavation depths. We request to be provided with such information as it becomes available. In Federal Register, Volume 54, No. 29 (October 1989), the United States Department of Labor, Occupational Safety and Health Administration (OSHA) amended its "Construction Standards for Excavations, 29 CFR, part 1926, Subpart P". This document was issued to better insure the safety of workmen entering trenches or excavations. It is mandated by this federal regulation that excavations, whether they be utility trenches, basement excavations or footing excavations, be constructed in accordance with the new OSHA guidelines. It is our understanding that these regulations are being strictly enforced and if they are not closely followed, the owner and the contractor could be liable for substantial penalties. The contractor is solely responsible for designing and constructing stable, temporary excavations and should shore, slope, or bench the sides of the excavations as required to maintain stability of both the excavation sides and bottom. The contractor's "responsible person", as defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of the contractor's safety procedures. In no case should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and federal safety regulations. We are providing this information solely as a service to our client. PSI does not assume responsibility for construction site safety or the contractor's or other parties compliance with local, state, and federal safety or other regulations. 15

19 5 REPORT LIMITATIONS The recommendations submitted in this revised report are based on the available subsurface information obtained by PSI and design details furnished by Mr. K. Scott Brown for the proposed project. If there are any revisions to the plans for this project, or if deviations from the subsurface conditions noted in this report are encountered during construction, PSI should be notified immediately to determine if changes in the recommendations are required. If PSI is not notified of such changes, PSI will not be responsible for the impact of those changes on the project. It is our opinion the findings, recommendations, specifications, or professional advice contained herein have been provided in accordance with generally accepted professional geotechnical engineering practices in the local area. No other warranties are implied or expressed. After the plans and specifications are more complete, the geotechnical engineer should be retained and provided the opportunity to review the final design plans and specifications to check that our engineering recommendations have been properly incorporated into the design documents. At this time, it may be necessary to submit supplementary recommendations. This report has been prepared for the exclusive use of Clark, Geer, Latham & Associates, Inc. for the specific application to the proposed Dollar Tree in Springfield, Tennessee. 16

20 APPENDIX A 17

21 P-1 B-1 P-2 B-3 B-2 B-4 APPROXIMATE BORING LOCATION Project Name: Dollar Tree Project Location: Springfield, Tennessee PSI Project # : Client: Clark, Geer, Latham & Associates, Inc. 751 South 5th Street Date: January 214 Nashville, Tennessee 3726 Boring Location Plan

22 APPENDIX B 18

23 GENERAL NOTES FINE AND COARSE GRAINED SOIL PROPERTIES COARSE GRAINED SOILS FINE GRAINED SOILS PARTICLE SIZE (SANDS & GRAVELS) (SILTS & CLAYS) BOULDERS: GREATER THAN 3 mm N-VALUE RELATIVE DENSITY N-VALUE CONSISTENCY Qu, PSF COBBLES: 75 mm to 3 mm -4 VERY LOOSE -2 VERY SOFT -5 GRAVEL: 4.74 mm to 75 mm 5-1 LOOSE 3-4 SOFT 5-1 COARSE SAND: 2 mm to,4.75 mm 11-3 MEDIUM DENSE 5-8 FIRM 1-2 MEDIUM SAND:.425 mm to 2 mm 31-5 DENSE 9-15 STIFF 2-4 FINE SAND:.75 mm to.425 mm OVER 5 VERY DENSE 16-3 VERY STIFF 4-8 SILTS & CLAYS: LESS THAN.75 mm OVER 31 HARD 8+ STANDARD PENETRATION TEST (ASTM D1586) THE STANDARD PENETRATION TEST AS DEFINED BY ASTM D1586 IS A METHOD TO OBTAIN A DISTURBED SOIL SAMPLE FOR EXAMINATION AND TESTING AND TO OBTAIN RELATIVE DENSITY AND CONSISTENCY INFORMATION. THE 1.4 INCH I.D./2. INCH O.D. SAMPLER IS DRIVEN 3-SIX INCH INCREMENTS WITH A 14 LB. HAMMER FALLING 3 INCHES. THE BLOW COUNTS REQUIRED TO DRIVE THE SAMPLER THE FINAL 2 INCREMENTS ARE ADDED TOGETHER AND DESIGNATE THE N-VALUE. AT TIMES, THE SAMPLER CAN NOT BE DRIVEN THE FULL 18 INCHES. THE FOLLOWING PRESENTS OUR INTERPRETATION OF THE STANDARD PENETRATION TEST WITH VARIATIONS. BLOWS/FOOT (N-VALUE) DESCRIPTION BLOWS'DROVE SAMPLER 12" AFTER INITIAL6" SEATING 75/1" BLOWS DROVE SAMPLER 1" AFTER INITIAL6" SEATING 5/PR... SAMPLER ENCOUNTERED PENETRATION REFUSAL AFTER 5 BLOWS WITH NO PENETRATION 5/2, BLOWS DROVE SAMPLER 2" AFTER NO INITIAL 6" SEATING KEY TO MATERIAL CLASSIFICATION TOPSOIL LIMESTONE BEDROCK ",I >, SOIL FILL MATERIAL CRUSHED LIMESTONE CL LEAN CLAY SANDSTONE SOIL PROPERTY SYMBOLS N: STANDARD PENETRATION, BPF M; MOISTURE CONTENT, % LL: LIQUID LIMIT, % PI; PLASTICITY INDEX, % Op: POCKET PENETROMETER VALUE, TSF Ou: UNCONFINED COMPRESSIVE STRENGTH, TSF DUW; DRY UNIT WEIGHT, PCF CH FAT CLAY SILTSTONE ML MH SP SC SM LOW PLASTIC SILT HIGH PLASTIC SILT POORLY GRADED SAND CLAYEY SAND SILTY SAND SHALE GRAVEL SHOTROCK FILL ASPHALT CONCRETE SAMPLING SYMBOLS I UNDISTURBED SAMPLE L2J SPLIT SPOON SAMPLE o ROCK CORE SAMPLE I] AUGER OR BAG SAMPLE :g WATER LEVEL AFTER DRILLING! WATER LEVEL AFTER 24 HRS ROCK PROPERTIES ROCK QUALITY DESIGNATION (RQD) ROCK HARDNESS PERCENT ROD 9to 1 75 to 9 5 to to 5 o to 25 QUALITY EXCELLENT GOOD FAIR POOR VERY POOR VERY SOFT: SOFT: MODERATELY.HARD: HARD: ROCK DISINTEGRATES OR EASILY COMPRESSES TO TOUCH; CAN BE HARD TO VERY HARD SOIL. ROCK IS COHERANT BUT BREAKS EASILY TO THUMB PRESSURE AT SHARP EDGES AND CRUMBLES WITH FIRM HAND PRESSURE. SMALL PIECES CAN BE BROKEN OFF ALONG SHARP EDGES BY CONSIDERABLE HARD THUMB PRESSURE; CAN BE BROKEN BY LIGHT HAMMER BLOWS. ROCK' CANNOT BE BROKEN BY THUMB PRESSURE, BUT CAN BE BROKEN BY MODERATE HAMMER BLOWS. l""'~;1 Information ~..". To Build On VERY HARD: ROCK CAN BE BROKEN BY HEAVY HAMMER BLOWS.

24 DATE STARTED: 1/3/14 DRILL COMPANY: PSI, Inc. DRILLER: ES LOGGED BY: COMPLETION DEPTH 15. ft DRILL RIG: CME-55 DATE COMPLETED: 1/3/14 BORING B-1 BENCHMARK: ELEVATION: LATITUDE: LONGITUDE: STATION: OFFSET: REMARKS: Elevation (feet) Depth, (feet) Graphic Log Sample Type Sample No. 1 Recovery (inches) MATERIAL DESCRIPTION 7" TOPSOIL Red to Dark Yellow Brown Lean CLAY with roots, chert, and silt, moist, firm to very stiff. USCS Classification N=6 Moisture, % 23 Water STANDARD PENETRATION TEST DATA N in blows/ft PL Moisture LL 25 5 STRENGTH, tsf Qu While Drilling Upon Completion Delay DRILLING METHOD: Hollow Stem Auger SAMPLING METHOD: SS HAMMER TYPE: Automatic BORING LOCATION: EFFICIENCY REVIEWED BY: WM SPT Blows per 6-inch (SS) 2. Qp 4. Additional Remarks None None 5 2 CL N= N= Dark Yellow Brown to Red Fat CLAY with chert and silt, moist, very stiff N=18 19 CH 15 5 Boring Terminated 15. Feet N=19 27 Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) PROJECT NO.: PROJECT: Dollar Tree LOCATION: E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 1

25 DATE STARTED: 1/2/14 DRILL COMPANY: PSI, Inc. DRILLER: ES LOGGED BY: COMPLETION DEPTH 2. ft DRILL RIG: CME-55 DATE COMPLETED: 1/2/14 BORING B-2 BENCHMARK: ELEVATION: LATITUDE: LONGITUDE: STATION: OFFSET: REMARKS: Elevation (feet) Depth, (feet) Graphic Log Sample Type Sample No. 1 Recovery (inches) 1" TOPSOIL MATERIAL DESCRIPTION Red Brown to Dark Yellow Brown to Red Lean CLAY with roots and silt, moist, soft to very stiff. USCS Classification N=4 Moisture, % 23 Water STANDARD PENETRATION TEST DATA N in blows/ft PL Moisture LL 25 5 STRENGTH, tsf Qu While Drilling Upon Completion Delay DRILLING METHOD: Hollow Stem Auger SAMPLING METHOD: SS HAMMER TYPE: Automatic BORING LOCATION: EFFICIENCY REVIEWED BY: WM SPT Blows per 6-inch (SS) 2. Qp feet 5.5 feet Additional Remarks 2 CL HW-HW-6 N= Red to Dark Yellow Brown Lean CLAY with silt and chert, moist, very stiff. CL N=21 22 LL = 32 PL = Dark Yellow Brown to Red Lean CLAY with silt and chert, moist to wet, very stiff N=21 25 CL 15 5 Red to Dark Yellow Brown Fat CLAY with chert, moist, soft to firm N=3 28 CH 2 6 Boring Terminated 2. Feet N=8 26 Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) PROJECT NO.: PROJECT: Dollar Tree LOCATION: E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 1

26 DATE STARTED: 1/2/14 DRILL COMPANY: PSI, Inc. DRILLER: ES LOGGED BY: COMPLETION DEPTH 15. ft DRILL RIG: CME-55 DATE COMPLETED: 1/2/14 BORING B-3 BENCHMARK: ELEVATION: LATITUDE: LONGITUDE: STATION: OFFSET: REMARKS: Elevation (feet) Depth, (feet) Graphic Log Sample Type Sample No. 1 Recovery (inches) 8" TOPSOIL MATERIAL DESCRIPTION FILL - Red Lean CLAY with chert, moist, very soft. USCS Classification CL N=2 Moisture, % 25 Water STANDARD PENETRATION TEST DATA N in blows/ft PL Moisture LL 25 5 STRENGTH, tsf Qu While Drilling Upon Completion Delay DRILLING METHOD: Hollow Stem Auger SAMPLING METHOD: SS HAMMER TYPE: Automatic BORING LOCATION: EFFICIENCY REVIEWED BY: WM SPT Blows per 6-inch (SS) 2. Qp feet 5.5 feet Additional Remarks 2 Gray to Red Brown to Red Lean CLAY with silt, roots, and chert, moist to wet, very stiff to soft. HW-HW-1 N= CL HW-2-2 N=4 1 4 Red Brown to Gray to Dark Yellow Brown to Red Fat CLAY with chert, moist to wet, stiff N=14 23 CH 15 5 Boring Terminated 15. Feet N=14 26 Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) PROJECT NO.: PROJECT: Dollar Tree LOCATION: E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 1

27 DATE STARTED: 1/2/14 DRILL COMPANY: PSI, Inc. DRILLER: ES LOGGED BY: COMPLETION DEPTH 15. ft DRILL RIG: CME-55 DATE COMPLETED: 1/2/14 BORING B-4 BENCHMARK: ELEVATION: LATITUDE: LONGITUDE: STATION: OFFSET: REMARKS: Elevation (feet) Depth, (feet) Graphic Log Sample Type Sample No. 1 Recovery (inches) MATERIAL DESCRIPTION 6" GRAVEL 4" TOPSOIL FILL - TOPSOIL/GRAVEL Mix, firm. USCS Classification N=7 Moisture, % Water STANDARD PENETRATION TEST DATA N in blows/ft PL Moisture LL 25 5 STRENGTH, tsf Qu While Drilling Upon Completion Delay DRILLING METHOD: Hollow Stem Auger SAMPLING METHOD: SS HAMMER TYPE: Automatic BORING LOCATION: EFFICIENCY REVIEWED BY: WM SPT Blows per 6-inch (SS) 2. Qp 4. Additional Remarks None None 2 Gray to Dark Yellow Brown to Red Brown to Dark Red Lean CLAY with silt, roots, and trace chert, moist to wet, firm to stiff N=8 22 LL = 33 PL = N=12 22 CL N= Red to Gray to Dark Yellow Brown Fat CLAY with chert and silt, moist, very stiff. Boring Terminated 15. Feet. CH N=21 32 Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) PROJECT NO.: PROJECT: Dollar Tree LOCATION: E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 1

28 DATE STARTED: 1/3/14 DRILL COMPANY: PSI, Inc. DRILLER: ES LOGGED BY: COMPLETION DEPTH 1. ft DRILL RIG: CME-55 DATE COMPLETED: 1/3/14 BORING P-1 BENCHMARK: ELEVATION: LATITUDE: LONGITUDE: STATION: OFFSET: REMARKS: Elevation (feet) Depth, (feet) 5 Graphic Log Sample Type Sample No Recovery (inches) MATERIAL DESCRIPTION 7" TOPSOIL Gray to Dark Yellow Brown to Light Brown Lean CLAY with silt, roots, and chert, moist, stiff to very stiff. Dark Yellow Brown to Red to Gray Fat CLAY with chert and silt, moist, very stiff. USCS Classification CL CH SPT Blows per 6-inch (SS) N= N= N=16 Moisture, % Water STANDARD PENETRATION TEST DATA N in blows/ft PL Moisture LL 25 5 STRENGTH, tsf Qu While Drilling Upon Completion Delay DRILLING METHOD: Hollow Stem Auger SAMPLING METHOD: SS HAMMER TYPE: Automatic BORING LOCATION: EFFICIENCY REVIEWED BY: WM 2. Qp 4. Additional Remarks None None 1 4 Boring Terminated 1. Feet N=19 24 Note: Offset 9. feet southwest due to drainage ditch. Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) PROJECT NO.: PROJECT: Dollar Tree LOCATION: E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 1

29 DATE STARTED: 1/3/14 DRILL COMPANY: PSI, Inc. DRILLER: ES LOGGED BY: COMPLETION DEPTH 1. ft DRILL RIG: CME-55 DATE COMPLETED: 1/3/14 BORING P-2 BENCHMARK: ELEVATION: LATITUDE: LONGITUDE: STATION: OFFSET: REMARKS: Elevation (feet) Depth, (feet) Graphic Log Sample Type Sample No. Recovery (inches) 16" TOPSOIL MATERIAL DESCRIPTION USCS Classification Moisture, % Water STANDARD PENETRATION TEST DATA N in blows/ft PL Moisture LL 25 5 STRENGTH, tsf Qu While Drilling Upon Completion Delay DRILLING METHOD: Hollow Stem Auger SAMPLING METHOD: SS HAMMER TYPE: Automatic BORING LOCATION: EFFICIENCY REVIEWED BY: WM SPT Blows per 6-inch (SS) 2. Qp 4. 1 foot 1 foot Additional Remarks 1 Gray Brown to Dark Yellow Brown Lean CLAY with roots and chert, wet, soft. CL HW-2-2 N= No Recovery. HW-HW-3 N=4 5 3 Dark Red to Gray to Dark Yellow Brown Fat CLAY with chert, moist, firm to stiff N=6 28 CH 1 4 Boring Terminated 1. Feet N=12 27 Note: Offset 15. feet northeast due to drainage ditch. Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) PROJECT NO.: PROJECT: Dollar Tree LOCATION: E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee The stratification lines represent approximate boundaries. The transition may be gradual. Sheet 1 of 1

30 APPENDIX C 19

31 6 5 P L A S T I C I T Y 4 3 CL CH I N D E X 2 1 CL-ML ML MH LIQUID LIMIT Boring Depth (ft) LL PL PI Fines Classification (*Visual) B B Red to Dark Yellow Brown Lean CLAY. (CL) Gray to Dark Yellow Brown to Dark Red Lean CLAY. (CL) Professional Service Industries, Inc. 751 South 5th Street Nashville, TN 3726 Telephone: (615) Fax: (615) PSI Job No.: Project: Location: ATTERBERG LIMIT RESULTS Dollar Tree E. 17th St. & Old Greenbrier Rd. Springfield, Tennessee