Proposed Family Dollar Store Watford City, North Dakota. 7B Building & Development Lubbock, Texas January 26, Terracon Project No.

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1 Proposed Family Dollar Store Watford City, North Dakota Terracon Project No. M Prepared for: 7B Building & Development Lubbock, Texas January 26, 2017

2 January 26, B Building & Development County Road 1820 Lubbock, TX Attn: Re: Mr. Trevor King P: [281] E: Proposed Geotechnical Engineering Services Proposed Family Dollar Store Watford City, North Dakota Terracon Project No. M Mr. King: Terracon Consultants, Inc. (Terracon) is pleased to submit our Geotechnical Engineering Report for the above referenced project. This work was performed in accordance with our proposal number PM , dated November 14, We trust that this report is responsive to your project needs. Please contact us if you have any questions or if we can be of further assistance. We appreciate the opportunity to work with you on this project and look forward to providing additional geotechnical engineering services in the future. Sincerely, Terracon Consultants, Inc. Jonathan J. Malaterre, EI Staff Engineer Loel M. Fetting, PE Senior Engineer Terracon Consultants, Inc N 42nd Street Unit B Grand Forks, ND P [701] terracon.com

3 REPORT TOPICS* PROJECT DESCRIPTION EXPLORATION AND TESTING PROCEDURES SITE CONDITIONS GEOTECHNICAL MODEL SEISMIC CONSIDERATIONS GEOTECHNICAL OVERVIEW SITE PREPARATION SHALLOW FOUNDATIONS FLOOR SLABS PAVEMENTS GENERAL COMMENTS ATTACHMENTS SITE LOCATION EXPLORATION PLAN EXPLORATION RESULTS (Boring Logs and Laboratory Data) SUPPORTING INFORMATION (General Notes and USCS, etc.) *This is a paper rendition of a web-based Geotechnical Engineering Report. Responsive Resourceful Reliable

4 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M PROJECT DESCRIPTION Our initial understanding of the project was provided in our proposal and was discussed in the project planning stage. A period of collaboration has transpired since the project was initiated and our final understanding of the project conditions is as follows: Item Project location Proposed structure Building construction Maximum loads Grading/slopes Below grade construction Retaining Walls Pavements Description The project site is located at the intersection 4 th Avenue Northeast and 6 th Avenue Northeast in Watford City. The project will include an approximately 8,400 square foot building with an associated parking lot. The proposed building will be metal framed with a floor slab on grade. Columns: 100 kips Walls: 3 kips per linear foot Slabs: 100 pounds per square foot Finished floor elevation is expected to within 2 feet of the existing grade. Cuts/fill up to 2 feet. None None Both rigid (concrete) and flexible (asphalt) pavement sections are being considered. Anticipated Traffic is as follows: Autos/Light Trucks: 80 vehicles per day Light Delivery and Trash Collection Vehicles: 10 vehicles per week Tractor-trailer trucks: Less than 1 vehicle per week. The pavement design period is 20 years. Responsive Resourceful Reliable PROJECT DESCRIPTION 1

5 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M EXPLORATION AND TESTING PROCEDURES Our field exploration work includes the drilling and sampling of exploratory soil borings consistent with the following schedule. Number of Borings Boring Depth (feet) Planned Location 4 20 Building 2 5 Parking lot The borings were advanced at the approximate locations indicated on our Exploration Plan. The boring locations were established in the field by Terracon s exploration team using a hand-held GPS unit. The accuracy of the exploration points is usually within 20 feet of the noted location. The ground surface elevations were found using a surveyor s level rod referencing to a temporary benchmark (see Exploration Plan). The borings were advanced with a track-mounted drill rig using 3 ¼ inch hollow stem augers. Soil samples were obtained using split-barrel sampling procedures. In the split-barrel sampling procedure the number of blows required to advance a standard 2-inch O.D., 1-3/8-inch I.D spiltbarrel sampler from 6 to 18 inches of penetration by means of a 140-pound hammer with a free fall of 30 inches is used to obtain the Standard Penetration Test (SPT) or N-value. The SPT is used to estimate the in-situ relative density of cohesionless soils and the consistency of cohesive soils. An automatic SPT hammer was used to advance the split-barrel sampler in the borings performed at this site. A greater efficiency is typically achieved with the automatic hammer compared to the conventional safety hammer operated with a cathead and rope. Published correlations between the SPT values and soil properties are based on the lower efficiency cathead and rope method. This higher efficiency affects the standard penetration resistance blow count (N) value by increasing the penetration per hammer blow over what would be obtained using the cathead and rope method. The effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of the subsurface information for this report. The samples were tagged for identification, sealed to reduce moisture loss, and taken to our laboratory for further examination, testing, and classification. Information provided on the boring logs attached to this report includes soil descriptions, consistency evaluations, boring depths, sampling intervals, and groundwater conditions. A field log of each boring was prepared by the drill crew. These logs included visual classifications of the materials encountered during drilling as well as the driller s interpretation of the subsurface conditions between samples. Final boring logs included with this report represent the engineer's Responsive Resourceful Reliable EXPLORATION AND TESTING PROCEDURES 1

6 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M interpretation of the field logs and include modifications based on laboratory observation and tests of the samples. Laboratory Testing The project engineer will review the field data and assign various laboratory tests to better understand the engineering properties of the various soil and rock strata as necessary for this project. Procedural standards noted below are for reference to methodology in general. In some cases, variations to methods are applied as a result of local practice or professional judgment. Standards noted below include reference to other, related standards. Such references are not necessarily applicable to describe the specific tests that will be performed. ASTM D Standard Test Methods for Laboratory Determination of Water (Moisture) Content of Soil and Rock by Mass ASTM D422-63(2007)e2 Standard Test Method for Particle-Size Analysis of Soils ASTM D e1 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils ASTM D2166/D2166M-13 Standard Test Method for Unconfined Compressive Strength of Cohesive Soil ASTM D Standard Test Methods for Laboratory Determination of Density (Unit Weight) of Soil Specimens The laboratory testing program may often include examination of soil samples by an engineer. Based on the material s texture and plasticity, we describe and classify the soil samples in accordance with the Unified Soil Classification System. Responsive Resourceful Reliable EXPLORATION AND TESTING PROCEDURES 2

7 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M SITE CONDITIONS The following description of site conditions is derived from our site visit in association with the field exploration and our review of publically available geologic and topographic maps. Item Location Existing improvements Current ground cover Existing topography Description The project site is located at the intersection of 4 th Avenue Northeast and 6 th Avenue Northeast in Watford City, North Dakota. Approximate Coordinates: 47 48' " N, ' " W None Agricultural field Relatively level Responsive Resourceful Reliable SITE CONDITIONS 1

8 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M GEOTECHNICAL MODEL Groundwater Groundwater was not observed in the remaining borings while drilling, or for the short duration that the borings were allowed to remain open. Based on our measurement data and moisture condition of the sands encountered at the site, it appears the water table was below the depth of our borings at the time of our field work. Groundwater level fluctuations occur due to seasonal variations in the amount of rainfall, runoff and other factors not evident at the time the borings were performed. Therefore, groundwater levels during construction or at other times in the life of the structure may be higher or lower than the levels indicated on the boring logs. The possibility of groundwater level fluctuations should be considered when developing the design and construction plans for the project. Responsive Resourceful Reliable GEOTECHNICAL MODEL 1

9 GEOTECHNICAL MODEL Proposed Family Dollar 1/26/2017 WATFORD CITY, NORTH DAKOTA Terracon Project No. M B-6 B B B B ELEVATION (MSL) () B Distance Along Baseline - Feet Fill (made ground) Topsoil Clayey Sand Silty Sand with Gravel Sandy Lean Clay Silty Sand Model Layer Termed General Description Model Layer Termed General Description 1 FILL-LEAN CLAY WITH SAND brown, trace gravel, frozen 2 FILL- SILTY SAND fine grained, light olive brown to dark brown, frozen to 3' 3 ORGANIC CLAY black, buried topsoil 6 SILTY SAND fine grained, light yellowish brown to light olive brown, loose to medium dense 7 SILTY SAND WITH fine to coarse grained, brown, loose to medium dense GRAVEL 4 CLAYEY SAND light olive brown, mottled, medium stiff to very stiff, trace gravel 5 SANDY LEAN CLAY light olive brown, stiff, trace gravel NOTES: See boring logs for more detailed conditions specific to each boring. GeoModel provided for illustration purposes only. Actual subsurface conditions between borings will vary. Layering shown on this figure has been developed by the geotechnical engineer for purposes of characterization of subsurface conditions as required for the subsequent geotechnical engineering for this project. LEGEND First Water Observation Second Water Observation Final Water Observation

10 Proposed Family Dollar Watford City, North Dakota January 25, 2017 Terracon Project No. M SEISMIC CONSIDERATIONS Design of buildings and other structures subject to earthquake ground motions requires classification of the upper 100 feet of the site profile in accordance with Chapter 20 of ASCE 7. The Site Class types are listed below and are basically defined by an average value of either shear wave velocity, standard penetration resistance, or undrained shear strength. A. Hard Rock B. Rock C. Very dense soil and soft rock D. Stiff soil E. Soft clay soil F. Soils vulnerable to potential failure or collapse under seismic loading Based on the results of our site characterization program, we conclude that Site Class D is appropriate for the subject site. Note that the scope of services did not include site profile determination to a depth of 100 feet. Explorations for this project extended to a maximum depth of 20 feet and the site classification assumes that materials encountered at the bottom of the deepest exploration continue to a depth of 100 feet. Based upon our Expected Geotechnical Conditions, we expect that the soil conditions below the maximum explored depth are consistent with the Site Class noted for this site. Responsive Resourceful Reliable SEISMIC CONSIDERATIONS 1

11 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M GEOTECHNICAL OVERVIEW Borings B-2 through B-5 were advanced in the proposed building area and encountered approximately 2 feet of uncontrolled fill underlain by silty sands and buried topsoil to depths ranging from 3 ½ to 4 ½ feet below existing grade. The fill and topsoil is underlain by silty sands and clayey sands that extend to the termination depth of our borings. The Site Preparation section provides recommendations for removal and replacement of the uncontrolled fill and topsoil from beneath the building foundations and floor slabs. The Floor Slab section addresses slab-on-grade support of the building. We recommend the foundations and floor slabs bear on natural inorganic soils or the well compacted granular fill placed after the removal of topsoil and uncontrolled fill. Borings B-1 and B-6 were advanced in the proposed parking lot of the Family Dollar and encountered approximately 2 feet of uncontrolled fill underlain by silty sand and buried topsoil to depths ranging from 2 to 4 ½ feet below the existing grade. We recommend removing the uncontrolled fill and buried topsoil and replacing it with controlled engineered fill before the construction of the parking lot. The Site Preparation section provides recommendations for removal of the uncontrolled fill and buried topsoil. The silty and clayey soils encountered at the site are also susceptible to movement due to frost action. These subgrade soils will experience heaving in the winter months and subsequent loss of strength during spring thaw. Therefore, pavement movement and cracking should be expected due to the extreme temperature changes which will occur. The Pavement section addresses design and construction of pavement systems. Responsive Resourceful Reliable GEOTECHNICAL OVERVIEW 1

12 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M SITE PREPARATION Prior to placing engineered fill or concrete, we recommend all buried topsoil, existing fill, any existing improvements, and any otherwise unsuitable materials be excavated from the proposed building area and appropriate horizontal excavation oversize. Based on the soil conditions encountered at our boring locations, we estimate excavation depths would be on the order of 2 to 4 ½ feet below the existing grade. Material Types Engineered fill should meet the following material property requirements: Fill Type 1 USCS Classification Acceptable Location for Placement Select granular fill Inorganic on-site native soils SP, SP-SM, SP-SC, SW, SW-SM, SW-SC, SM, SC (P200<12%) SC, SM Support of foundations, floor slabs and pavements Exterior foundation backfill, fill below pavements, and utility trench backfill 2 1. Controlled, compacted fill should consist of approved materials that are free of particles larger than about 3 inches, organic matter and debris. Frozen material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the geotechnical engineer for evaluation. 2. Utility trenches should be backfilled with native clay soils to minimize the potential for differential frost heave. Compaction Requirements Engineered fill should meet the following compaction requirements: Fill Lift Thickness Item Minimum Compaction Requirements 1 Description 9-inches or less in loose thickness when heavy, selfpropelled compaction equipment is used 4 to 6 inches in loose thickness when hand-guided equipment (i.e. jumping jack or plate compactor) is used 98% beneath foundations 95% beneath floor slabs 98% for fill below pavements (upper 2 feet) 95% for fill below pavements (below 2 feet) 90% for exterior backfill below grassed areas Responsive Resourceful Reliable SITE PREPARATION 1

13 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M Moisture Content Cohesive Soils Moisture Content Granular Material 2 ± 3 percent of optimum Workable moisture levels 1. The moisture content and compaction should be measured for each lift of engineered fill during placement. Should the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved. Compaction levels are relative to the maximum dry density as determined by ASTM D Specifically, moisture levels should be maintained low enough to allow for satisfactory compaction to be achieved without the cohesionless fill material pumping when proofrolled. Fill Construction Observation and Testing Each lift of compacted fill should be tested, evaluated, and reworked, as necessary, until approved by the geotechnical engineer s representative prior to placement of additional lifts. We recommend that each lift of fill be tested for density and moisture content at a frequency of one test for every 2,500 square feet of compacted fill in the building areas and 5,000 square feet in pavement areas. We recommend one density and moisture content test for every 50 linear feet of compacted utility trench backfill at variable trench depths. Utility Trench Backfill Utility trenches are a common source of water infiltration and migration. All utility trenches that penetrate beneath the building should be effectively sealed to restrict water intrusion and flow through the trenches that could migrate below the building. Excavations should be performed in accordance with governing safety regulations. All vehicles and soil piles should be kept back from the crest of excavation slopes. The stability of excavation slopes should be reviewed continuously by qualified personnel. The responsibility for excavation safety and temporary construction slopes lies solely with the contractor. Trenches that remain open for an extended period of time should be protected by changes in moisture by covering with plastic sheeting or another suitable method. Grading and Drainage All grades must provide effective drainage away from the building during and after construction. Estimated movement described in this report are based on effective drainage for the life of the structure and cannot be relied upon if effective drainage is not maintained. The roof should have gutters/drains with downspouts that discharge onto splash blocks at a distance of at least 10 feet from the building. Responsive Resourceful Reliable SITE PREPARATION 2

14 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M Exposed ground should be sloped and maintained at a minimum 10 percent (5 percent where pavement will abut the building, or less to comply with ADA requirements) away from the building for at least 10 feet beyond the perimeter of the building. After building construction and landscaping, we recommend verifying final grades to document that effective drainage has been achieved. Grades around the structure should also be periodically inspected and adjusted as necessary, as part of the structure s maintenance program. Where paving or flatwork abuts the structure, we recommend a maintenance program to effectively seal and maintain joints to prevent surface water infiltration. Earthwork Construction Considerations The natural soils are susceptible to disturbance during construction. Therefore, we recommend excavating be performed by a backhoe with a smooth cutting surface. Construction traffic should not be allowed to travel directly on the exposed soils. If any of the natural soils become disturbed they should be replaced with engineered fill or concrete. Surface water should not be allowed to pond on the site and soak into the soil during construction. Construction staging should provide drainage of surface water and precipitation away from the building areas. Any water that collects over or adjacent to construction areas should be promptly removed, along with any softened or disturbed soils. Surface water control in the form of sloping surfaces, drainage ditches and trenches, and sump pits and pumps will be important to avoid ponding and associated delays due to precipitation and seepage. Sidewalks and pavements should be expected to experience frost heaving over winter months. Flat exterior grades adjacent to the building can result in sidewalk/pavement elevations projecting above slabs supported on stoop foundations creating a potential trip hazard over winter months. We recommend placement of a minimum of 4 feet of clean sand fill below exterior slabs adjacent to the structure. Additionally, we recommend sloping the sand fill at 3:1 (H:V) to transition between the deep and shallow subcut areas to avoid differential frost heave. As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926, Subpart P, Excavations and its appendices, and in accordance with any applicable local, state, and federal safety regulations. The contractor should be aware that slope height, slope inclination, and excavation depth should in no instance exceed those specified by these safety regulations. Flatter slopes than those dictated by these regulations may be required depending upon the soil conditions encountered and other external factors. These regulations are strictly enforced and if they are not followed, the owner, contractor, and/or earthwork and utility subcontractor could be liable and subject to substantial penalties. Construction site safety is the sole responsibility of the contractor who controls the means, methods and sequencing of construction operations. Under no circumstances shall the information provided herein be interpreted to mean that Terracon is assuming any responsibility Responsive Resourceful Reliable SITE PREPARATION 3

15 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M for construction site safety or the contractor's activities; such responsibility shall neither be implied nor inferred. Terracon should be retained during the construction phase of the project to observe earthwork and to perform necessary tests and observations during subgrade preparation; placement and compaction of controlled compacted fills; backfilling of excavations into the completed subgrade, and just prior to construction of building floor slabs. Responsive Resourceful Reliable SITE PREPARATION 4

16 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M SHALLOW FOUNDATIONS Design Parameters Parameter Isolated Columns Continuous Maximum net allowable bearing pressure on existing soils or engineered fill 1 3,000 psf 3,000 psf Minimum foundation dimensions 30 inches 18 inches Ultimate coefficient of sliding friction 0.32 Ultimate passive pressure pcf, equivalent passive pressure Minimum embedment below finished grade for frost protection 3 6 feet 6 feet Minimum embedment below finished grade for frost protection 4 7 feet 7 feet Est. total settlement from structural loads 5 < 1 inch < 1 inch Estimated differential settlement 5 < ½ inch < ½ inch 1. The maximum net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. 2. The shallow foundation excavation sides must be nearly vertical and the concrete should be placed near against these vertical faces for the passive earth pressure values to be valid. Passive resistance in the upper 5 feet of the soil profile should be neglected. If passive resistance is used to resist lateral loads, the base friction should be neglected. Apply a factor of safety of at least 2.0 to this value when designing for lateral force resistance. 3. For perimeter footings beneath continuously heated areas. Interior footings in heated areas can be supported on engineered fill at a convenient depth below the floor slab, provided topsoil and expansive soils are removed and replaced with controlled engineered fill (sand). 4. For footings beneath unheated areas. 5. Settlements as a result of the structural loads as noted in Project Description. The foundation settlement will depend on variations within the subsurface soil profile, actual structural loading conditions, and the quality of the earthwork operations. Foundation Construction Considerations The base of all foundation excavations should be free of water and loose soil prior to placing concrete. Concrete should be placed soon after excavating to reduce bearing soil disturbance. Care should be taken to prevent wetting or drying of the bearing materials during construction. Responsive Resourceful Reliable SHALLOW FOUNDATIONS 1

17 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M Extremely wet or dry material or any loose or disturbed material in the bottom of the footing excavations should be removed before foundation concrete is placed. Should the soils at bearing level become excessively dry, disturbed, saturated, or frozen, the affected soil should be removed prior to placing concrete. If unsuitable bearing soils are encountered in footing excavations, the excavations should be extended deeper to suitable soils and the footings could bear directly on these soils at the lower level or on lean concrete backfill placed in the excavations. The footings could also bear on properly compacted backfill extending down to the suitable soils. Overexcavation for compacted backfill placement below footings should extend laterally beyond all edges of the footings at least 8 inches per foot of overexcavation depth below footing base elevation. The overexcavation should then be backfilled up to the footing base elevation with well-graded granular material placed in lifts of 9 inches or less in loose thickness and compacted to at least 98 percent of the material s maximum standard effort maximum dry density (ASTM D698). The overexcavation and backfill procedures are described in the figures below. Exterior slabs supported on the native soils will be subject to frost heaving. At exterior doorways, we recommend exterior slabs be supported on stoop foundations at frost depth with a void below the stoop slabs to prevent uplift from frost action. Responsive Resourceful Reliable SHALLOW FOUNDATIONS 2

18 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M FLOOR SLABS We recommend the removal of the existing uncontrolled fill and buried topsoil below the floor slabon-grade and replacement with a well compacted engineered fill in accordance with the Site Preparation section of this report. Design Parameters Floor slab support Item Modulus of subgrade reaction Aggregate base course/capillary break 1 Description Engineered fill (sand) after removal of uncontrolled fill and topsoil 150 pounds per square inch per inch (psi/in) for point loading conditions 6 inches of free draining granular material 1. The floor slab design should include a capillary break, comprised of free-draining, compacted granular material at least 6 inches thick. Free-draining material granular material should have less than 5 percent fines (material passing the No. 200 sieve). The use of a vapor retarder should be considered beneath concrete slabs on grade that will be covered with wood, tile, carpet or other moisture sensitive or impervious coverings, or when the slab will support equipment sensitive to moisture. When conditions warrant the use of a vapor retarder, the slab designer should refer to ACI 302 and/or ACI 360 for procedures and cautions regarding the use and placement of a vapor retarder. Floor Slab Construction Considerations On most project sites, the site grading is generally accomplished early in the construction phase. However as construction proceeds, the subgrade may be disturbed due to utility excavations, construction traffic, desiccation, rainfall, etc. As a result, the floor slab subgrade may not be suitable for placement of base rock and concrete, and corrective action will be required. Terracon should review the condition of the floor slab subgrades immediately prior to placement of the granular leveling course and construction of the slabs. Particular attention should be paid to high traffic areas that were rutted and disturbed earlier and to areas containing backfilled trenches. Areas where unsuitable conditions are located should be repaired by removing and replacing the affected material with properly compacted fill. Responsive Resourceful Reliable FLOOR SLABS 1

19 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M PAVEMENTS General Notes The silty and clayey soils encountered at the site are susceptible to movement from frost heaving. Therefore, the completed lot will experience frost heaving over the winter months and a subsequent loss of strength during spring thaw. The pavement will be subject to movement and cracking due to the extreme temperatures that will occur. The recommendations below should provide serviceable parking and drive areas. Subgrade Preparation The borings performed near the parking area encountered uncontrolled fill and buried topsoil from depths ranging from 2 to 4 ½ feet below the existing grade. We recommend removal of all uncontrolled and buried topsoil below pavement areas and replacement with a well compacted inorganic soil. We recommend the exposed subgrade soils be scarified to a depth of one foot, and recompacted as recommended in the Site Preparation section. The moisture content and compaction recommendations for the exposed subgrade and imported fill are provided in the Site Preparation section. We recommend the subgrade soils be proofrolled prior to pavement construction. Areas where unsuitable conditions are located should be repaired by removing and replacing the material with properly compacted fills. Design Considerations Pavement designs are provided for the traffic conditions and pavement life conditions as noted in Project Description. Designs for minimum thicknesses for new pavement sections for this project have been based on the procedures outlined in the 1993 Guideline for Design of Pavement Structures by the American Association of State Highway and Transportation Officials (AASHTO- 1993) and in the Guide for the Design and Construction of Concrete Parking Lots (ACI 330R-08). Our analysis is based on the anticipated traffic loading consisting of primarily light delivery and trash collection vehicles, automobiles and light trucks. If the anticipated traffic loading is different than the values used in our analysis, we should be contacted so we may review our pavement recommendations. Pavement performance is affected by its surroundings. In addition to providing preventive maintenance, the civil engineer should consider the following recommendations in the design and layout of pavements: Responsive Resourceful Reliable PAVEMENTS 1

20 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M Final grade adjacent to paved areas should slope down from the edges at a minimum 2%; The subgrade and pavement surface should have a minimum 2% slope to promote proper surface drainage; Install below pavement drainage systems surrounding areas anticipated for frequent wetting; Install joint sealant and seal cracks immediately; Seal all landscaped areas in or adjacent to pavements to reduce moisture migration to subgrade soils; Place compacted, low permeability backfill against the exterior side of curb and gutter; and, Place curb, gutter and/or sidewalk directly on clay subgrade soils rather than on unbound granular base course materials. Minimum Pavement Thickness Traffic Area PCC Pavement ACC Pavement Vehicle Parking Drive Lanes/ Entrances/Exits 5 PCC Pavement 1 4 ACC Pavement 2 6 Aggregate Base Course 3 6 Aggregate Base Course 3 6 PCC Pavement 1 5 ACC Pavement 2 8 Aggregate Base Course 3 8 Aggregate Base Course 3 1. For the PCC pavement, we recommend a mix meeting the requirements of NDDOT Section 802 type AAE. 2. For the ACC pavement, we recommend a mix meeting the requirements of NDDOT Section type FAA The base course should meet the requirements of North Dakota Class 5. We recommend the aggregate base course be placed in loose lift thicknesses of six inches or less and compacted to a minimum of 100 percent of the maximum density as determined by ASTM D698. We recommend an appropriate geotextile fabric be placed between the subgrade and the granular base material. The fabric will serve as a separation barrier during wet seasonal conditions. Rigid PCC pavements will perform better than ACC in areas where short-radii turning and braking are expected (i.e. entrance/exit aprons) due to better resistance to rutting and shoving. In addition, PCC pavement will perform better in areas subject to large or sustained loads. An adequate number of longitudinal and transverse control joints should be placed in the rigid pavement in accordance with ACI and/or AASHTO requirements. Expansion (isolation) joints must be full depth and should only be used to isolate fixed objects abutting or within the paved area. Pavement Drainage Pavements should be sloped to provide rapid drainage of surface water. Water allowed to pond on or adjacent to the pavements could saturate the subgrade and contribute to premature Responsive Resourceful Reliable PAVEMENTS 2

21 Proposed Family Dollar Watford City, North Dakota January 26, 2017 Terracon Project No. M pavement deterioration. In addition, the pavement subgrade should be graded to provide positive drainage within the granular base section. Appropriate sub-drainage or connection to a suitable daylight outlet should be provided to remove water from the granular subbase. Pavement Maintenance The pavement sections represent minimum recommended thicknesses and, as such, periodic maintenance should be anticipated. Therefore preventive maintenance should be planned and provided for through an on-going pavement management program. Maintenance activities are intended to slow the rate of pavement deterioration and to preserve the pavement investment. Maintenance consists of both localized maintenance (e.g. crack and joint sealing and patching) and global maintenance (e.g. surface sealing). Preventive maintenance is usually the first priority when implementing a pavement maintenance program. Additional engineering observation is recommended to determine the type and extent of a cost effective program. Even with periodic maintenance, some movements and related cracking may still occur and repairs may be required. Responsive Resourceful Reliable PAVEMENTS 3

22 Proposed Family Dollar Store Watford City, North Dakota January 26, 2017 Terracon Project No. M GENERAL COMMENTS Our work is conducted with the understanding of the project as described in the proposal, and will incorporate collaboration with the design team prior to completing our services. Terracon has requested verification of all stated assumptions. Revision of our understanding to reflect actual conditions important to our work will be based on these verifications and will be reflected in the final report. The design team should collaborate with Terracon to confirm these assumptions. The design team should also collaborate with Terracon to prepare the final design plans and specifications. This facilitates the incorporation of our opinions related to implementation of our geotechnical recommendations. Our analysis and opinions are based upon our understanding of the geotechnical conditions in the area, the data obtained from the site exploration performed and from our understanding of the project. Variations will occur between exploration point locations, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. So, Terracon should be retained to provide observation and testing services during grading, excavation, foundation construction and other earth-related construction phases of the project. If variations appear, we can provide further evaluation and supplemental recommendations. If variations are noted in the absence of our observation and testing services on-site, we should be immediately notified so that we can provide evaluation and supplemental recommendations. Our scope of services does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken. Our services and any correspondence are intended for the exclusive use of our client for specific application to the project discussed and are accomplished in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site characteristics as provided are for design purposes and not to estimate excavation cost. Any use of our report in that regard is done at the sole risk of the excavating cost estimator as there may be variations on the site that are not apparent in the data that could significantly impact excavation cost. Any parties charged with estimating excavation costs should seek their own site characterization for that specific purposes to obtain the specific level of detail necessary for costing. Site safety, and cost estimating including, excavation support, and dewatering requirements/design are the responsibility of others. In the event that changes in the nature, design, or location of the project are planned, our conclusions and recommendations shall not be Responsive Resourceful Reliable GENERAL COMMENTS 1

23 Proposed Family Dollar Store Watford City, North Dakota January 26, 2017 Terracon Project No. M considered valid unless we review the changes and either verify or modify our conclusions in writing. Responsive Resourceful Reliable GENERAL COMMENTS 2

24 SITE TOPOGRAPHIC MAP IMAGE COURTESY OF THE U.S. GEOLOGICAL SURVEY QUADRANGLES INCLUDE: WATFORD CITY, ND (1/1/1978) and SCHAFER, ND (1/1/1997). DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES Project Manager: jjm Drawn by: Checked by: Approved by: jjm lmf lmf Project No. M Scale: 1 =2,000 File Name: Date: 12/6/ N 42nd Street, Unit B Grand Forks, ND SITE LOCATION Proposed Family Dollar Store 4 th Avenue Northeast & 6 th Avenue Northeast Watford City, North Dakota

25 AERIAL PHOTOGRAPHY PROVIDED BY MICROSOFT BING MAPS DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES Project Manager: jjm Drawn by: Checked by: Approved by: jjm lmf lmf Project No. M Scale: AS SHOWN File Name: Date: 1/25/ N 42nd Street, Unit B Grand Forks, ND EXPLORATION PLAN Proposed Family Dollar Store 4th Avenue Northeast & 6 th Avenue Northeast Watford City, North Dakota

26 PROJECT: Proposed Family Dollar BORING LOG NO. B-1 7B Building & Development CLIENT: Lubbock, Texas Page 1 of 1 SITE: GRAPHIC LOG MODEL LAYER 1 LOCATION 4th Avenue & 6th Avenue Watford City, North Dakota See Exploration Plan Latitude: Longitude: Surface Elev.: (Ft.) DEPTH ELEVATION (Ft.) FILL - LEAN CLAY WITH SAND, brown, trace gravel, frozen DEPTH (Ft.) WATER LEVEL OBSERVATIONS SAMPLE TYPE RECOVERY (Ft.) FIELD TEST RESULTS LABORATORY TORVANE/HP (psf) UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI PERCENT FINES FILL - SILTY SAND, fine grained, dark brown, frozen to 3' ORGANIC CLAY (OH), black, (buried topsoil) CLAYEY SAND (SC), brown, stiff, trace gravel Boring Terminated at 6 Feet N= N= THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL M GPJ TERRACON2015.GDT 1/26/17 Stratification lines are approximate. In-situ, the transition may be gradual. Advancement Method: 3 ¼ inch Hollow Stem Auger Abandonment Method: Borings backfilled with soil cuttings upon completion. WATER LEVEL OBSERVATIONS See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations N 42nd ST Unit B Grand Forks, ND Hammer Type: Automatic Notes: 2' : Blow counts influenced by frost depth Boring Started: 1/10/2017 Boring Completed: 1/10/2017 Drill Rig: Dietrich D-90 Driller: MAR Project No.: M

27 PROJECT: Proposed Family Dollar BORING LOG NO. B-2 7B Building & Development CLIENT: Lubbock, Texas Page 1 of 1 SITE: GRAPHIC LOG MODEL LAYER 1 LOCATION 4th Avenue & 6th Avenue Watford City, North Dakota See Exploration Plan Latitude: Longitude: Surface Elev.: (Ft.) DEPTH ELEVATION (Ft.) FILL - LEAN CLAY WITH SAND, brown, trace gravel, frozen DEPTH (Ft.) WATER LEVEL OBSERVATIONS SAMPLE TYPE RECOVERY (Ft.) FIELD TEST RESULTS LABORATORY TORVANE/HP (psf) UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI PERCENT FINES ORGANIC CLAY (OH), black, (buried topsoil), frozen to 3' SILTY SAND WITH GRAVEL (SM), fine to coarse grained, brown, medium dense CLAYEY SAND (SC), light olive brown, mottled, very stiff to stiff, trace gravel N= N= THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL M GPJ TERRACON2015.GDT 1/26/ SANDY LEAN CLAY (CL), light olive brown, stiff, trace gravel SILTY SAND (SM), fine grained, light yellowish brown, medium dense 21.5 Boring Terminated at 21.5 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Advancement Method: 3 ¼ inch Hollow Stem Auger Abandonment Method: Borings backfilled with soil cuttings upon completion. WATER LEVEL OBSERVATIONS 1 hour after completion of drilling N 42nd ST Unit B Grand Forks, ND See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations N= N= N= Hammer Type: Automatic Notes: ' : Blow counts influenced by frost depth 4.5' : Mechanical analysis. See test results Boring Started: 1/10/2017 Drill Rig: Dietrich D-90 Project No.: M Boring Completed: 1/10/2017 Driller: MAR

28 PROJECT: Proposed Family Dollar BORING LOG NO. B-3 7B Building & Development CLIENT: Lubbock, Texas Page 1 of 1 SITE: GRAPHIC LOG MODEL LAYER 1 LOCATION 4th Avenue & 6th Avenue Watford City, North Dakota See Exploration Plan Latitude: Longitude: Surface Elev.: (Ft.) DEPTH ELEVATION (Ft.) FILL - LEAN CLAY WITH SAND, brown, trace gravel, frozen DEPTH (Ft.) WATER LEVEL OBSERVATIONS SAMPLE TYPE RECOVERY (Ft.) FIELD TEST RESULTS LABORATORY TORVANE/HP (psf) UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI PERCENT FINES FILL - SILTY SAND, fine grained, dark brown, frozen to 3' N= ORGANIC CLAY (OH), black, (buried topsoil) SILTY SAND WITH GRAVEL (SM), fine to coarse grained, brown, medium dense to loose CLAYEY SAND (SC), light olive brown, mottled, medium stiff to very stiff to stiff, trace gravel N= N= THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL M GPJ TERRACON2015.GDT 1/26/ SILTY SAND (SM), fine grained, light olive brown, medium dense, trace gravel 21.0 Boring Terminated at 21 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Advancement Method: 3 ¼ inch Hollow Stem Auger Abandonment Method: Borings backfilled with soil cuttings upon completion. WATER LEVEL OBSERVATIONS N 42nd ST Unit B Grand Forks, ND See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations N= N= N= Hammer Type: Automatic Notes: ' : Blow counts influenced by frost depth 4.5' : Mechanical analysis. See test results Boring Started: 1/10/2017 Drill Rig: Dietrich D-90 Project No.: M Boring Completed: 1/10/2017 Driller: MAR

29 PROJECT: Proposed Family Dollar BORING LOG NO. B-4 7B Building & Development CLIENT: Lubbock, Texas Page 1 of 1 SITE: GRAPHIC LOG MODEL LAYER 1 LOCATION 4th Avenue & 6th Avenue Watford City, North Dakota See Exploration Plan Latitude: Longitude: Surface Elev.: (Ft.) DEPTH ELEVATION (Ft.) FILL - LEAN CLAY WITH SAND, dark brown, trace gravel, frozen DEPTH (Ft.) WATER LEVEL OBSERVATIONS SAMPLE TYPE RECOVERY (Ft.) FIELD TEST RESULTS LABORATORY TORVANE/HP (psf) UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI PERCENT FINES FILL - SILTY SAND, fine grained, dark brown, frozen to 3' N= ORGANIC CLAY (OH), black, (buried topsoil) CLAYEY SAND (SC), light olive brown, mottled, stiff to medium stiff to stiff, trace gravel N= N= THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL M GPJ TERRACON2015.GDT 1/26/ SILTY SAND (SM), fine grained, light olive brown, loose 21.0 Boring Terminated at 21 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Advancement Method: 3 ¼ inch Hollow Stem Auger Abandonment Method: Borings backfilled with soil cuttings upon completion. WATER LEVEL OBSERVATIONS N 42nd ST Unit B Grand Forks, ND See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations N= N= N= Hammer Type: Automatic Notes: ' : Blow counts influenced by frost depth 9.5' : Mechanical analysis. See test results Boring Started: 1/10/2017 Drill Rig: Dietrich D-90 Project No.: M Boring Completed: 1/10/2017 Driller: MAR 46

30 PROJECT: Proposed Family Dollar BORING LOG NO. B-5 7B Building & Development CLIENT: Lubbock, Texas Page 1 of 1 SITE: GRAPHIC LOG MODEL LAYER 1 LOCATION 4th Avenue & 6th Avenue Watford City, North Dakota See Exploration Plan Latitude: Longitude: Surface Elev.: (Ft.) DEPTH ELEVATION (Ft.) FILL - LEAN CLAY WITH SAND, dark brown, trace of gravel, frozen DEPTH (Ft.) WATER LEVEL OBSERVATIONS SAMPLE TYPE RECOVERY (Ft.) FIELD TEST RESULTS LABORATORY TORVANE/HP (psf) UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI PERCENT FINES FILL - SILTY SAND, fine grained, dark brown, frozen ORGANIC CLAY (OH), black, (buried topsoil) CLAYEY SAND (SC), light olive brown, stiff, trace gravel N= N= THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL M GPJ TERRACON2015.GDT 1/26/ SANDY LEAN CLAY (CL), light olive brown, stiff, trace gravel SILTY SAND (SM), fine grained, light yellowish brown, dense to medium dense 21.0 Boring Terminated at 21 Feet Stratification lines are approximate. In-situ, the transition may be gradual. Advancement Method: 3 ¼ inch Hollow Stem Auger Abandonment Method: Borings backfilled with soil cuttings upon completion. WATER LEVEL OBSERVATIONS N 42nd ST Unit B Grand Forks, ND See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations N= N= N= N= Hammer Type: Automatic Notes: ' : Blow counts influenced by frost depth 14.5' : Mechanical analysis. See test results Boring Started: 1/10/2017 Drill Rig: Dietrich D-90 Project No.: M Boring Completed: 1/10/2017 Driller: MAR 24

31 PROJECT: Proposed Family Dollar BORING LOG NO. B-6 7B Building & Development CLIENT: Lubbock, Texas Page 1 of 1 SITE: GRAPHIC LOG MODEL LAYER LOCATION DEPTH ELEVATION (Ft.) FILL - LEAN CLAY WITH SAND, brown, trace gravel, frozen th Avenue & 6th Avenue Watford City, North Dakota See Exploration Plan Latitude: Longitude: Surface Elev.: (Ft.) ORGANIC CLAY (OH), black, (buried topsoil), frozen SILTY SAND (SM), fine grained, light olive brown, medium dense, frozen to 3' DEPTH (Ft.) WATER LEVEL OBSERVATIONS SAMPLE TYPE RECOVERY (Ft.) 1.3 FIELD TEST RESULTS N=15 LABORATORY TORVANE/HP (psf) UNCONFINED COMPRESSIVE STRENGTH (psf) WATER CONTENT (%) 5 DRY UNIT WEIGHT (pcf) ATTERBERG LIMITS LL-PL-PI PERCENT FINES CLAYEY SAND (SC), light olive brown, very stiff, trace gravel Boring Terminated at 6 Feet N= THIS BORING LOG IS NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GEO SMART LOG-NO WELL M GPJ TERRACON2015.GDT 1/26/17 Stratification lines are approximate. In-situ, the transition may be gradual. Advancement Method: 3 ¼ inch Hollow Stem Auger Abandonment Method: Borings backfilled with soil cuttings upon completion. WATER LEVEL OBSERVATIONS See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any). See Supporting Information for explanation of symbols and abbreviations N 42nd ST Unit B Grand Forks, ND Hammer Type: Automatic Notes: 2' : Blow counts influenced by frost depth Boring Started: 1/10/2017 Boring Completed: 1/10/2017 Drill Rig: Dietrich D-90 Driller: MAR Project No.: M

32 ATTERBERG LIMITS RESULTS ASTM D LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. ATTERBERG LIMITS M GPJ TERRACON2015.GDT 1/25/17 P L A S T I C I T Y I N D E X "U" Line CL or OL CH or OH "A" Line MH or OH CL-ML ML or OL LIQUID LIMIT Boring ID Depth LL PL PI Fines USCS Description B-3 B PROJECT: Proposed Family Dollar SITE: 4th Avenue & 6th Avenue Watford City, North Dakota SC SC 1555 N 42nd ST Unit B Grand Forks, ND CLAYEY SAND CLAYEY SAND PROJECT NUMBER: M CLIENT: 7B Building & Development Lubbock, Texas

33 PERCENT FINER BY WEIGHT GRAIN SIZE DISTRIBUTION ASTM D422 / ASTM C136 U.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS / /4 3/ HYDROMETER LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. GRAIN SIZE: USCS-2 M GPJ TERRACON2015.GDT 1/25/ Boring ID B-2 B-3 B-4 B-5 Boring ID B-2 B-3 B-4 B-5 COBBLES 100 Depth Depth coarse PROJECT: Proposed Family Dollar SITE: 4th Avenue & 6th Avenue Watford City, North Dakota GRAVEL D fine GRAIN SIZE IN MILLIMETERS coarse D 60 medium SAND USCS Classification SILTY SAND WITH GRAVEL (SM) SILTY SAND WITH GRAVEL (SM) CLAYEY SAND (SC) SILTY SAND (SM) fine D 30 D N 42nd ST Unit B Grand Forks, ND 0.1 WC (%) %Gravel SILT OR CLAY LL PL PI %Sand PROJECT NUMBER: M Cc Cu %Silt %Fines %Clay CLIENT: 7B Building & Development Lubbock, Texas

34 UNCONFINED COMPRESSION TEST ASTM D2166 7,000 COMPRESSIVE STRESS - psf 6,000 5,000 4,000 3,000 2,000 LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. UNCONFINED WITH PHOTOS M GPJ TERRACON2012.GDT 1/25/17 1, SPECIMEN FAILURE PHOTOGRAPH SAMPLE TYPE: Shelby Tube SAMPLE DESCRIPTION: CLAYEY SAND PROJECT: Proposed Family Dollar SITE: 4th Avenue & 6th Avenue Watford City, North Dakota AXIAL STRAIN - % Height / Diameter Ratio: Calculated Void Ratio: Assumed Specific Gravity: Unconfined Compressive Strength Undrained Shear Strength: Remarks: SPECIMEN TEST DATA Moisture Content: % Dry Density: Diameter: Height: LL PL PI pcf Calculated Saturation: % Failure Strain: % Strain Rate: SAMPLE LOCATION: 1555 N 42nd ST Unit B Grand Forks, ND in. in. (psf) (psf) in/min 7-9 feet Percent < #200 Sieve PROJECT NUMBER: M CLIENT: 7B Building & Development Lubbock, Texas

35 UNCONFINED COMPRESSION TEST ASTM D2166 7,000 COMPRESSIVE STRESS - psf 6,000 5,000 4,000 3,000 2,000 LABORATORY TESTS ARE NOT VALID IF SEPARATED FROM ORIGINAL REPORT. UNCONFINED WITH PHOTOS M GPJ TERRACON2012.GDT 1/25/17 1, SPECIMEN FAILURE PHOTOGRAPH SAMPLE TYPE: Shelby Tube SAMPLE DESCRIPTION: CLAYEY SAND PROJECT: Proposed Family Dollar SITE: 4th Avenue & 6th Avenue Watford City, North Dakota AXIAL STRAIN - % Height / Diameter Ratio: Calculated Void Ratio: Assumed Specific Gravity: Unconfined Compressive Strength Undrained Shear Strength: Remarks: SPECIMEN TEST DATA Moisture Content: % Dry Density: Diameter: Height: LL PL PI pcf Calculated Saturation: % Failure Strain: % Strain Rate: SAMPLE LOCATION: 1555 N 42nd ST Unit B Grand Forks, ND in. in. (psf) (psf) in/min feet Percent < #200 Sieve PROJECT NUMBER: M CLIENT: 7B Building & Development Lubbock, Texas