GEOTECHNICAL INVESTIGATION. Proposed RETAIL DEVELOPEMNT 1300 W. Pflugerville Parkway Pflugerville, Texas PROJECT NO. 17-DG8780.

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1 GEOTECHNICAL INVESTIGATION PROJECT NO. 17-DG8780 Prepared for: PROFESSIONAL STRUCIVIL ENGINEERS, INC Austin, Texas Prepared by: GEOSCIENCE ENGINEERING & TESTING, INC. Dallas, Texas October, Satsuma Drive, Suite 400 Dallas, Texas (P)

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3 CONTENTS INTRODUCTION Project Description... 1 Site Description... 1 Purposes and Scope of Work... 1 Report Format... 1 FIELD INVESTIGATION... 2 LABORATORY TESTING... 2 Review... 3 GENERAL SUBSURFACE CONDITIONS Stratigraphy... 3 Subsurface Water Conditions... 3 ANALYSIS AND RECOMMENDATIONS Construction Consultation and Monitoring... 4 Soil Movement... 4 FOUNDATION RECOMMENDATIONS A. Straight Shaft Piers... 5 Soil Induced Uplift Loads... 5 Pier Installation... 6 Grade Beams... 6 Floor Systems... 7 B. Slab-on-Grade Type Foundation System... 9 Building Pad Preparation Select Fill Select Fill PAVEMENT AND SUBGRADE SITE GRADING and DRAINAGE CLOSURE ILLUSTRATIONS LOCATION PLAN... A BORING LOGS GEOSCIENCE, Inc.

4 INTRODUCTION Project Description This report presents the results of a Geotechnical Investigation performed by our firm at the referenced project located in. Based on the project information provided, it is our understanding that construction will consist of a retail and C-store buildings, a canopy and associated parking and driveway area. Information regarding structural loads was not available at the time of this investigation; however, we anticipate the loads will be light. It is expected that the finished floor elevation of the proposed building will be above the surrounding surfaces. Site Description The site of the referenced project is located at e in the City of. At the time of this investigation, the study area was undeveloped land. The general location and orientation of the site is shown in the Illustrations section of this report. Purposes and Scope of Work The principal purposes of this investigation were to 1). Develop subsurface soil and rock stratigraphy at the boring locations; 2). Evaluate soil swell potential and provide alternatives to reduce soil movement; 3). Provide recommendations for foundation design parameters; 4). Provide pavement recommendations and 5). Provide site preparation recommendations. Report Format The first sections of this report describe the field and laboratory phases of the study. The remaining sections present our engineering analysis that was used to develop geotechnical parameters for the type of foundation system proposed for this site. Boring logs and laboratory test results are presented in the Illustrations section of this report. GEOSCIENCE, Inc

5 FIELD INVESTIGATION To explore the subsurface conditions, seven (7) test borings were drilled and sampled. Test borings B-1 to B-5 were drilled to a depth of 20 feet below ground surface at the location of building pads and remaining test borings B-6 and B-7 were drilled to a depth of 5 feet in the paved area. The approximate locations of the borings are indicated on Plate A in the Illustrations Section of this report. Boring logs with descriptions of the soils sampled are attached on Plates 1 and 7. Soil strata boundaries shown on the boring logs are approximate. The borings were advanced using continuous flight auger techniques. Undisturbed cohesive soil samples were obtained using a 3-inch diameter thin-walled tube sampler pushed into the soils. The un-drained compressive strength of cohesive soils was estimated in the field using a calibrated pocket penetrometer. A Standard Penetration sampler was used at selected depths to obtain a standard penetration value (N value). An N-value is defined as the number of blows a 140-pound hammer free falling from 30 inches would require to drive a two-inch O.D. sampler one foot into undisturbed soils below the bottom of the bore hole. The N value is an indication of the relative density of noncohesive soils. The results of the standard penetration tests, expressed as "blows per foot," are tabulated at the respective sample depths on the boring logs. All soil samples were removed or extruded from the samplers in the field, visually classified, and placed in appropriate containers to prevent loss of moisture or disturbance during transfer to the laboratory. The borings were advanced using dry auger procedures to observe the water level at the time of the exploration. These water level observations are recorded on the boring logs. LABORATORY TESTING Engineering properties of the foundation soils were evaluated in the laboratory by tests performed on representative soil samples. A series of moisture content tests were performed to develop soil moisture profiles at the boring locations and to aid in evaluating the uniformity of soil conditions. Plastic and liquid limit (Atterberg limits) and percentage passing number 200 sieve tests were performed on selected samples from the borings to confirm visual classification and to evaluate soil volume change potentials. Shear strengths of cohesive soils were estimated by field pocket penetrometer tests. The results of these tests are presented on the boring logs. The results of the laboratory tests are presented on the boring logs. GEOSCIENCE, Inc

6 Review Descriptions of subsurface materials obtained in the field at the time the boring was drilled were modified in accordance with results of laboratory tests and visual examination in the laboratory. All recovered soil samples were examined and classified in accordance with ASTM D 2487, and described as recommended in ASTM D 2488 and the Unified Soil Classification procedures. Classification of the soils and finalized material descriptions are shown on the boring logs. GENERAL SUBSURFACE CONDITIONS Stratigraphy Based on our interpretation of the borings drilled for this investigation, the subsurface stratigraphy at this site consists predominately of clay soils underlain by calcareous clay followed by tan weathered limestone. More specifically, the subsurface stratigraphy encountered within the depths of the test borings drilled for this study consisted of: Dark Brown/brown CLAY (CH) soils with calcareous nodules were encountered from existing ground surface elevation to a depth of 2 to 6 feet in test borings B-1 to B-3, B-5 and B-7, and to the completion depth of shallower test boring B-6 drilled. Below clay soils in test borings B-2, B-3, B-5 and B-7, and from existing ground surface elevation in test boring B-4, tan CALCAREOUS CLAY (CL) soils were encountered and remained visible to a depth of 4 to 8 feet in test borings B- 2 to B-5, and to the completion depth of shallower test boring B-7 drilled. Below 4 to 8 feet in all deeper test borings B-1 to B-5, tan weathered LIMESTONE with calcareous clay seams were encountered and remained visible to the completion depth of test borings B-1 to B-5 drilled. Detailed descriptions of the subsurface stratigraphies encountered at this site are presented on the test boring logs in the Illustrations Section of this report. Subsurface Water Conditions The borings were advanced using dry auger drilling procedures in order to observe any groundwater seepage levels. At the time of this investigation, No groundwater seepage was encountered at any of the test borings drilled for this study. However, it should be noted that, future construction activities may alter the surface and subsurface drainage characteristics of this site. As such, we suggest re-verifying the depth to groundwater just prior to and during GEOSCIENCE, Inc

7 construction. If there is a noticeable change from the conditions reported herein, this office should be notified immediately to review the effect that it may have on the design recommendations. Based on short-term observations, it is not possible to accurately predict the magnitude of subsurface water fluctuations that might occur. Also water seepage may encounter at the interface of clay and limestone particularly after a period of heavy rainfall. ANALYSIS AND RECOMMENDATIONS Construction Consultation and Monitoring We recommend that GETI be given an opportunity to review the final design drawings and specifications to ensure that the recommendations provided in this report have been properly interpreted. Wide variations in soil conditions are known to exist between the boring locations, particularly in the vicinity of this site. Further, unanticipated variations in subsurface conditions may become evident during construction. During the excavation and foundation phases of the project, we recommend that a reputable Geotechnical Engineering firm be retained to provide construction surveillance services in order to 1) observe compliance with the geotechnical design concepts, specifications and recommendations, and 2) observe subsurface conditions during construction to verify that the subsurface conditions are as anticipated, based on the boring performed for this investigation. Geoscience is available to perform the aforementioned services. Soil Movement The near surface subgrade soils encountered at this site exhibited plasticity indices between 16 and 60. These type soils are considered as moderately to extremely highly expansive in nature and are capable of significant vertical and horizontal ground movements due to soil swell and shrinkage which occurs with changes in soil moisture content(s). The magnitude of the movements experienced by the foundation will depend on one or a combination of several factors including the moisture content and the depth at which plastic soils are encountered at the time of construction, soil plasticity, rainfall moisture index, local drainage characteristics, and other related factors. Potential Vertical Movement was calculated using Texas Department of Transportation method (TxDOT 124-E). Based on the aforementioned method, the estimated moisture induced Potential vertical movement of the soils at the time of this investigation is 3.75 to 4.5 inches at existing GEOSCIENCE, Inc

8 ground surface at the locations of the borings drilled. Considerably more movement will occur in areas where water ponding is allowed to occur during and/or after construction -or- in areas where additional fill other than select fill is placed or- if the thickness of the clay soils is greater than that encountered in the test borings. Site grading may also increase the potential for the movement. FOUNDATION RECOMMENDATIONS A. Straight Shaft Piers The structural loads can be supported by auger excavated, straight-sided, steel reinforced, castin-place concrete piers. These piers should be founded at least 5 feet into the tan weathered limestone encountered at a depth of 4 to 8 feet at the location of deeper test borings drilled. The dimensions of the piers can be determined based on a net allowable bearing pressure of 18,000 psf and skin friction value of 2,500 psf in compression and tension. The skin friction component should only be applied to the portion of the shaft located in the pier-bearing stratum below the recommended minimum penetration. Soil Induced Uplift Loads The piers should be provided with enough steel reinforcement to resist the uplift pressures that will be exhibited by the near surface soils. We recommend the uplift pressures be approximated on the order of 1,600 pounds per square foot of shaft area over an average depth of 8 feet or top of the limestone, whichever is encountered first. The uplift can be neglected in the event select fill soils are placed to reduce the soil swell potential and can be reduced to 850 psf for moisture conditioned soils. To resist the net tensile load, the shaft must contain sufficient continuous vertical reinforcement to the full depth of the pier. Foundation piers designed and constructed in accordance with the information provided in this report will have a factor of safety in excess of 2.5 against shear type failure and will experience minimal settlement (less than one inch). GEOSCIENCE, Inc

9 Pier Installation The construction of all piers should be observed by experienced geotechnical personnel during construction to ensure compliance with design assumptions and to verify: (1) the bearing stratum; (2) the minimum penetration; (3) the removal of all smear zones and cuttings; (4) that groundwater seepage is correctly handled; and (5) that the shafts are vertical and within acceptable tolerance levels. Our Firm is available to provide these services upon request. Reinforcing steel and concrete should be placed immediately after the excavation has been completed and observed. In no event should a pier excavation be allowed to remain open for more than 8 hours. Concrete should be placed in such a manner to prevent segregation of the aggregates. In the event that perched water seepage is encountered at the time of the pier drilling operations and the depth of water at the bottom of the shaft cannot be maintained to less than 3 inches, temporary casing of the piers will be required. It should be noted that prior to the placement of concrete the water from the pier hole should be removed using a pump. Grade Beams Grade beams should be structurally connected into the top of the piers. The soils vertical movement can be reduced to less than one inch by placement of select fill soils or moisture conditioning method as per the procedures outlined in the later sections of this report. Alternatively, the grade beam can be suspended. A minimum void space of 8 inches should be provided beneath the beams. This void space allows movement of the soils below the grade beams without distressing the structural system. Structural cardboard forms are typically used to provide the void beneath grade beams. Cardboard forms used must have sufficient strength to support the concrete during construction. Our experiences indicate that major distress in grade beams will occur if the integrity of the void box is not maintained during construction. The excavation in which the void box lays must remain dry. Cardboard cartons can easily collapse during concrete placement if the cardboard becomes wet. Backfill material must not be allowed to enter the carton area below grade beams as this reduces the void space that underlying soils need to swell. GEOSCIENCE, Inc

10 Floor Systems i). Suspended Floor Slab in conjunction with pier type of foundation system: - The most positive floor system for pier type foundation systems in areas with expansive soils consists of a suspended floor system. The floor system of the proposed buildings should be structurally supported on the foundation piers and a minimum void space of 8 inches provided between the bottom of the slab and underlying soils. ii). Ground Supported Slab - A ground-supported slab may be considered for use at this site, provided the risk of some post-construction movement is acceptable. A ground-supported slab, if used, then the soils swell movement should be reduced to an inch or less by adopting one of the following methods: Placement of select fill soils: Remove subgrade soils to a depth of 4 feet or top of the limestone, whichever is encountered first, below finished grade and replace it with select fill soils. As mentioned earlier the uplift pressure will also be reduced to minimal by placement of select fill soils. We recommend that all the areas sensitive the soil swell potential should be included within the improvement; however, the upper 2 feet or depth of the grade beam whichever is deeper of select fill should not extend beyond the building line but rather should be capped with on-site high plasticity index clay soils in order to resist water seepage into the subgrade soils. Placement of expansive soils on the building pad will increase the potential for vertical movement; therefore, we recommend the use of select fill soils (specifications of which are outlined in the Select Fill Section of this report). The bottom of the select fill soils should be scarified to an additional 6 inches and compacted between 93 and 98 percent of maximum dry density with a minimum moisture content of 4 points above optimum as per ASTM D 698. Select fill materials should be placed in six (6) to eight (8)-inch loose lifts at moisture contents between optimum and 3 percentage points above optimum. Each lift compacted to between 95 and 100 percent of the maximum dry density as defined in ASTM D 698. Field density tests should be taken at the rate of at least one test per each 2,500 square feet, per lift, in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. -Or- GEOSCIENCE, Inc

11 Moisture conditioning method: To reduce the PVR to one inch, remove the all dark brown clay until tan limestone or calcareous clay soil is encountered, below finished grade and stockpile. The exposed surface area should be scarified to a depth of 6 inches and compacted to 93 and 97 percent of maximum dry density with moisture content of 4 points above optimum (3 point above optimum for soils with PI between 20 and 30). The previously removed soils should be placed back in the building pad area in 6 to 8 inches loose lifts and each lift should be compacted to between 93 and 98 percent of the maximum standard proctor dry density with a minimum moisture content of 4 points above optimum (3 point above for soils with PI between 20 and 30). We recommend the improvements extend an additional five feet beyond the perimeter of the building pad and should include all the areas sensitive to the movement. The upper one foot of the moisture conditioned soils should be capped with one foot of select fill soils -or- lime stabilized subgrade soils -or- flex base material. The Select fill material should be placed in two lifts at moisture contents between optimum and 3 percentage points above optimum. Each lift compacted to between 95 and 100 percent of the maximum dry density as defined in ASTM D 698. We recommend select fill soils not be extended beyond the building line however; the perimeter outside the grade beam should be capped with high plasticity index clay soils in order to retard any water seepage underneath the foundation. In the event that lime stabilization to the existing subgrade is planned as a cap, then it should be stabilized with a minimum of 36 pounds per square yard of lime for 6-inch-thick soils. If the flex base is used as a cap atop of moisture conditioned soils, then the flex base should be placed and compacted to a minimum of 98 percent of a maximum dry density as per ASTMD and the moisture content should be between -2 to +3 percent points above optimum. Field density tests should be taken at the rate of at least one test per each 2,500 square feet, per lift, in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. Construction of the building slab should start shortly upon completion of the subgrade improvement process. Moisture loss of the improved soils should not be allowed to occur between the time the improvement procedures are completed and the start of the construction. GEOSCIENCE, Inc

12 Based on the Terzaghi s Bearing Capacity theory a net allowable soil bearing pressure of 2,000 psf can be used to design the slab for select fill soils and 1,500 psf for moisture conditioned soils. These bearing pressures include a factor of safety of 2.5 with respect to shear failure. Floor slabs should be adequately reinforced to minimize any future cracking as normal movements occur in the foundation soils. Also, a moisture barrier of polyethylene sheeting or similar type material should be placed between the slab and the subgrade soils to retard moisture migration through the slab. We recommend that the building pad should be elevated to provide a proper drainage away from the building. It should be understood that a soil-supported foundation system will experience some movement over time. B. Slab-on-Grade Type Foundation In the event that the structural loads are light, and the cut/fill is ±2 feet, then a slab-on-grade type foundation system is a feasible option for use at this site provided: The risk of some post-construction movement is acceptable. Slab on grade type of foundation system require periodic cosmetic repairs to building finishes. Additionally, there is a risk that the ground movements could be greater than anticipated which could lead to the need for more extensive repairs. These circumstances are most often associated with poor drainage around the slab perimeter, sub-slab plumbing leaks, or trees or shrubs planted too close to the foundation. The potential for these movements, risks associated with long-term performance of slab-on-grade foundations, and owner/tenant maintenance responsibilities should be fully understood. The potential vertical rise should be reduced to less than one inch by placement of select fill soils or moisture conditioning method as per the procedures as outlined in the previous sections of this report. Additional fill soil if is required should consist of select fill soils. The slab may be of a grid-type grade beam and slab reinforced with conventional rebar foundation system. The foundation should be designed with exterior and interior grade beams adequate to provide sufficient rigidity to the foundation system and be able to resist the soil potential rise expected at this site. The beams should intersect at heavy load areas such as columns and the intersection may be widened and deepened to act as spread footings. The depth of the spread footing should be a minimum of 3 feet below finished grade and the grade GEOSCIENCE, Inc

13 beam should be a minimum of 2 feet deep and 12 inches wide and should be installed within compacted and tested select fill soils. A net allowable soil bearing pressure of 2,500 pounds per square foot may be used for design of spread footing bearing in select fill soils or flex base material (a minimum 2 feet of select fill/flex base is required below installation depth of footings) and 2,000 psf for moisture conditioned soils. The spread footings can be designed using a net allowable bearing pressure of 3,500 psf can be used in the event the footings are resting atop of or within the tan weathered limestone stratum. A net allowable soil bearing pressure of 2,000 psf can be used to design grade beams bearing in select fill soils and 1,500 psf for moisture conditioned soils, and 3,000 psf in the event the grade beam is resting atop of or within the tan weathered limestone stratum. The bottom of the beams should be free of any loose or soft material prior to the placement of the concrete. All grade beams and floor slabs should be adequately reinforced to minimize cracking as normal movements occur in the foundation soils. Also, a moisture barrier of polyethylene sheeting or similar material should be placed between the slab and the subgrade soils to retard moisture migration through the slab. It should be understood by all parties that a soil-supported foundation system will experience movement with time. Building Pad Preparation Prior to the placement of fill soils, all existing surface vegetation, loose fill (if any), trees and tree roots (if any) should be removed until hard stratum is encountered. For a suspended floor system, after removal of all above referenced items, all exposed surface from other areas of the building pad should then be scarified to 6 inches, watered as required and compacted to 95 to 100 percent of the maximum dry density, Moisture contents of the soils should be between optimum and 4 points above optimum. Additional fill, if is required, should consist of clean on site or off-site soils compacted to resist the initial concrete loads. Placement of select fill soils is not required for suspended floor system. For ground supported floor system: upon removal of all the referenced above items then the soils swell movement should be reduced to an inch or less by placement of select fill soils or moisture conditioning method as per the procedure outlined in previous sections of this report. Additional fill if is required then should consist of off-site select fill soils. GEOSCIENCE, Inc

14 Select fill should be placed in six (6) to eight (8)-inch loose lifts at moisture contents between optimum and 3 percentage points above optimum. Each lift compacted to between 95 and 100 percent of the maximum dry density as defined in ASTM D 698. Field density tests should be taken at the rate of one test per every 2,500 square feet per lift, or a minimum of 3 tests per lift in the area of all compacted fill. For areas where hand tamping is required, the testing frequency should be increased to approximately one test per lift, per 100 linear feet of area. Select Fill "Select fill," as referred to in this report, should consist of clayey sands free of organic materials with a Plasticity Index between 6 and 16, a Liquid Limit of 38 or less, and between 15 and 45 percent passing a No. 200 sieve. Placement and compaction of the select fill should be performed in accordance with the "Building Pad Preparation" section of this report. Flex Base TxDOT 247 Type 1. General PAVEMENT AND SUBGRADE RECOMMENDATIONS Specific wheel loading and traffic volume characteristics were not available at the time of this investigation. However, based on assumed loading conditions, we have developed the following Portland Cement Concrete Pavement design sections for use at this site: Light Traffic Portland Cement Concrete 5 Lime Stabilized Subgrade 6 Heavy Traffic Portland Cement Concrete 6 Lime Stabilized Subgrade 6 Minimum Thickness (inches) Prior to the placement of any fill in the pavement area, we recommend that all existing surface vegetation, loose fill (if any), trees and tree roots (if any) should be removed until hard stratum is encountered. The exposed surface soils should be scarified watered as required and compacted to 95 to 100 percent of maximum dry density as per ASTM D-698 with moisture GEOSCIENCE, Inc

15 content between optimum and 4 points above optimum. If additional fill is required, then on-site soils can be used and should be placed in 6 to 8 inches loos lifts and compacted to 95 to 100 percent of maximum dry density as per ASTM D-698 with moisture content between optimum and 4 points above optimum. The upper six inches of exposed soils should be stabilized with 6 to 8 percent (36 to 40 lbs/yard for 6 inches thick soil) of lime to stabilize the subgrade soils. It should be noted that after final grading is completed, the actual amount of lime required should be calculated by lime series tests performed in the laboratory. In the event lime stabilization is not economically feasible, then the concrete thickness should be increased by an additional one inch or City Standards. Design of the concrete pavement should specify a minimum 28-day concrete compressive strength of 3,000 psi with 4 to 6 percent entrained air. The concrete should be placed within one and one half hours of batching. During hot weather, concrete placement should follow ACI 311 Hot Weather concreting. In no case should concrete temperatures exceed 95ºF. Consideration should be given to limiting concrete placement to that time of day which will minimize large differences in the ambient and concrete temperature. Use of superplasticizer should be considered to improve the concrete workability without increasing water cement ratio. Pavements with sealed joints on 15 to 20-foot spacings cut to a depth of at least one-quarter of the pavement thickness, generally exhibit less uncontrolled post-construction cracking then pavements with wider spacings. Expansion joints should be used wherever the pavement is going to abut some type of structural fixture that was designed to undergo a different level of movement than the pavement (e.g. light poles, retaining walls, existing pavement, stairways, entryway piers, building walls, or manholes). The construction and expansion joints should be inspected periodically and resealed, if necessary. The loading dock and heavy traffic drive way should be reinforced using at least No. 3 bars, 24 inches on center. GEOSCIENCE, Inc

16 SITE GRADING and DRAINAGE All grading should provide positive drainage away from the proposed structures, and should prevent water from collecting or discharging near the foundations. Water must not be permitted to pond adjacent to the structures during or after construction. Surface drainage gradients should be designed to divert surface water away from the buildings and edges of pavements and towards suitable collection and discharge facilities. Unpaved areas and permeable surfaces should be provided with steeper gradients than paved areas. Pavement drainage gradients within 5 feet of buildings should be constructed with a minimum slope of one inch per foot to prevent negative drainage gradients (ponding water conditions) from developing due to differential upward pavement movements. Sidewalk drainage gradients should be along maximum slopes allowed by local codes. Roofs should be provided with gutters and downspouts to prevent the discharge of rainwater directly onto the ground adjacent to the building foundations. Downspouts should not discharge into any landscaped bed near the foundations. Downspouts should discharge directly into storm drains or drainage swales, if possible. Roof downspouts and surface drain outlets should discharge into erosion-resistant areas, such as paving or rock riprap. Recessed landscaped areas filled with pervious sandy loam or organic soil should not be used near the foundation. All trees should be a minimum of one-half their mature height away from the building or pavement edges to reduce potential moisture losses. Water permitted to pond in planters, open areas, or areas with unsealed joints next to structures can result in on-grade slab or pavement movements, which exceed those, indicated in this report. Exterior sidewalks and pavements will be subject to some post construction movement as indicated in this report. These potential movements should be considered during preparation of the grading plan. Flat grades should be avoided. Where concrete pavement is used, joints should be sealed to prevent the infiltration of water. Some post-construction movement of pavement and flatwork may occur. Particular attention should be given to joints around the building. These joints should be periodically inspected and resealed where necessary. GEOSCIENCE, Inc

17 CLOSURE It should be noted that some variations in soil and moisture conditions may exist between boring locations. Statements in this report as to subsurface variations over given areas are intended as estimations only, based upon the data obtained from specific boring locations. The results, conclusions, and recommendations contained in this report are directed at, and intended to be utilized within the scope of work outlined in this report. The report is not intended for use in any other manner. Geoscience Engineering and Testing, Inc., makes no claim or representation concerning any activity or condition falling outside the specified purposes for which this report is directed; said purposes being specifically limited to the scope of work as defined herein. Inquiries regarding scope of work, activities and/or conditions not specifically outlined herein, should be directed to GETI. The completed landscaping should be carefully inspected to verify that plantings properly drain. Soil in plantings may settle, which will tend to pond water, or plantings may block entrances to surface drains. Therefore, maintaining positive drainage from landscape irrigation will be an ongoing concern. GEOSCIENCE, Inc

18 ILLUSTRATIONS GEOSCIENCE, Inc.

19 Approximate Boring Location BORING LOCATION PLAN Proposed RETAIL DEVELOPMENT Project No. 17-DG8780 Plate A GEOSCIENCE, Inc.

20 LOG OF BORING NO. B-1 Proposed "Retail Development" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 10/07/2017 Completion Depth: 20 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous noduels WATER CONTENT, % 19 LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P N59/ 10" Tan weathered LIMESTONE with calcareous clay seams N71/ 11" N82/ 10" N50/ 2.2" REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 1

21 LOG OF BORING NO. B-2 Proposed "Retail Development" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 10/07/2017 Completion Depth: 20 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous noduels WATER CONTENT, % 14 LIQUID LIMIT 65 PLASTIC LIMIT 22 LABORATORY DATA PLASTICITY INDEX 43 UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P P4.5 8 Tan and occasional brown CALCAREOUS CLAY (CL) N78/ 11" Tan weathered LIMESTONE with calcareous clay seams N50/5" N50/3" REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 2

22 LOG OF BORING NO. B-3 Proposed "Retail Development" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5 STRATUM DEPTH (FT.) 2 Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 10/08/2017 Completion Depth: 20 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous noduels WATER CONTENT, % 32 LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) 5 P3.0 N87/ 10" 4 Tan and occasional brown CALCAREOUS CLAY (CL) Tan weathered LIMESTONE with calcareous clay seams N59/6" N71/ 10" N62/8" N50/2" REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 3

23 DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5+ STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA LOG OF BORING NO. B-4 Proposed "Retail Development" Date Boring Drilled: 10/08/2017 Completion Depth: 20 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Tan and occasional brown CALCAREOUS CLAY (CL) WATER CONTENT, % 12 LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) 5 P4.5+ N75/ 11" 4 Tan weathered LIMESTONE with calcareous clay seams N71/7" 8 10 N61/5" 9 15 N50/2" 9 20 N50/1" REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 4

24 LOG OF BORING NO. B-5 Proposed "Retail Development" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P2.0 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 10/08/2017 Completion Depth: 20 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous noduels WATER CONTENT, % 31 LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P2.5 6 Tan CALCAREOUS CLAY (CL) N85/ 11" Tan weathered LIMESTONE with calcareous clay seams N68/ 10" 7 15 N50/5" 8 20 N50/ 2.5" REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 5

25 LOG OF BORING NO. B-6 Proposed "Retail Development" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P3.0 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 10/08/2017 Completion Depth: 5 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules 22 WATER CONTENT, % LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 6

26 LOG OF BORING NO. B-7 Proposed "Retail Development" DEPTH (ft.) 0 FIELD DATA SOIL & ROCK SYMBOL TYPE P: HAND PEN., TSF T: THD, BLOWS/FT. N: SPT, BLOWS/FT. P4.5 STRATUM DEPTH (FT.) Location: See Location Plan Surface Elevation: Unknown Drilling Method: CFA Date Boring Drilled: 10/08/2017 Completion Depth: 5 Groundwater Information: Seepage Encountered During Drilling: None Upon Completion: Dry Project No. 17-DG8780 DESCRIPTION OF STRATUM Dark brown CLAY (CH) with calcareous nodules WATER CONTENT, % 15 LIQUID LIMIT PLASTIC LIMIT LABORATORY DATA PLASTICITY INDEX UNIT DRY WEIGHT (PCF) UNCONFINED STRENGTH (TSF) % PASSING NO. 200 SIEVE SOIL SUCTION TEST (TOTAL CM. OF WATER) P P Tan and occasional brown CALCAREOUS CLAY (CL) REMARKS: TUBE AUGER SPLIT- SPOON ROCK CORE THD CONE PEN. NO RECOVERY Geoscience Engineering & Testing Plate 7