TEAM Services. Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 2016 TABLE OF CONTENTS

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2 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services TABLE OF CONTENTS PROJECT INFORMATION... 1 SITE CONDITIONS... 1 FIELD EXPLORATION... 1 LABORATORY TEING... 2 Natural Moisture Content... 3 Unit Weight... 3 Unconfined Compressive Strength... 3 Plasticity (Atterberg Limits) Tests... 3 Torvane Shear Tests... 3 SUBSURFACE CONDITIONS... GROUNDWATER CONDITIONS... 6 CONUSIONS AND RECOMMENDATIONS... Expansive Soil Considerations... Existing Fill Considerations... Site Preparation... 9 Fill Placement Shallow Spread Foundation Design... Shallow Foundation Construction Floor Slabs... 1 Temporary Excavation Support... Construction Dewatering... Site Drainage... Pavement Subgrade Preparation... 1 Pavement Subdrains and Drainable Base Course... Pavement Thicknesses QUALIFICATION OF REPORT APPENDICES SITE LOCATION PLAN BORING PLAN LOGS OF BORINGS B-1 through B-15 and C-1 through C- SOIL PROFILES SP-1 through SP- ATTERBERG LIMITS TE REPORT A-1 UNIFIED SOIL AIFICATION SYEM GENERAL NOTES

3 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services PROJECT INFORMATION Project information has been provided by Mr. Pete Perez of Estes Construction in a Request for Proposal letter sent to our office, dated October 5, 20. Included with the letter was an aerial image showing proposed boring locations. The project will include a broad exploration for future building additions(s) and paving at Grant Wood Elementary in Bettendorf, Iowa. Details for the proposed addition(s) were not provided at the time of this report. SITE CONDITIONS The project site is located at 3 Hillside Drive in Bettendorf, Iowa. The site being explored is the area to the north, east, and south of the existing Grant Wood Elementary building. Near the building on the north, east, and south sides the site is made up of sidewalk, paving, a playground, and a grass courtyard with trees. The area farther to the south of the building is made up of a grass field, and a baseball diamond. The site is sloped to the southeast, and is terraced such that the site consists of two distinct pads and a drainage way on the far south end of the site along Parkway Drive. Surface soils were able to support our ATV-mounted auger drill rig without difficulty. FIELD EXPLORATION A total of 23 borings were conducted at this site to depths of 5 to 25 feet below existing grades on November th through 10 th, 20. The borings were located on the site, by TEAM Services personnel, using the provided site plan and referencing the surrounding site features. Final boring locations and ground surface elevations at the boring locations were obtained with survey-grade TOPCON GPS equipment utilizing the Iowa Real-Time Network. The approximate locations of the borings are shown on the attached Boring Plan in the Appendix. The locations and elevations of the borings should be considered accurate only to the degree implied by the means and methods used to define them. Page 1 of 22

4 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Our drilling equipment consisted of our ATV-mounted auger drill rig. The borings were made by mechanically twisting continuous flight hollow stem steel augers into the soil. At assigned intervals, the center drive bit of the hollow stem auger was removed and soil samples were obtained. Representative samples were obtained using thin-walled (Shelby) tube and split-barrel sampling procedures in general accordance with AM Specifications D 15 and D 156, respectively. In the thin-walled tube sampling procedure, a thin-walled, seamless steel tube with a sharp cutting edge is pushed hydraulically into the ground to obtain relatively undisturbed samples of cohesive or moderately cohesive soils. In the split-barrel sampling procedure, a standard 2-inch outer diameter split-barrel sampling spoon is driven into the ground with a 10-pound hammer falling a distance of 30 inches. The number of blows required to advance the sampling spoon the last inches of a normal -inch penetration is recorded as the standard penetration resistance value. These values are indicated on the Boring Logs at the depths of occurrence. The samples were tagged for identification, sealed and returned to the laboratory for testing and classification. Field logs of the borings were 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 an interpretation of the field logs and include modifications based on laboratory observation and tests of the samples. LABORATORY TEING Based on the driller's field records and examination of the samples in the laboratory, a soil testing program was developed to collect more information about the soil conditions at the site. The following is a brief description of the specific tasks completed for this project. Page 2 of 22

5 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Natural Moisture Content -- The natural moisture content of selected samples was determined in general accordance with AM D 22. The moisture content of the soil is the ratio, expressed as a percentage, of the weight of water in a given mass of soil to the weight of the soil particles. The results are presented on the Boring Logs at the depths from which the samples were obtained. Unit Weight -- In the laboratory, selected undisturbed samples of the site soils were measured and weighed to determine gross weight and volume of the samples. Where possible, the samples are placed in a template and trimmed at each end to fit the template. The moisture content of each specimen was then determined, and the dry unit weight was calculated. The results of these tests are also presented on the Boring Logs at the appropriate sample depths. Unconfined Compressive Strength -- A calibrated hand penetrometer was used to estimate the approximate unconfined compressive strength of select samples. The calibrated hand penetrometer has been correlated with unconfined compression tests and provides a better estimate of soil consistency than visual examination alone. Plasticity (Atterberg Limits) Tests -- Selected soil samples were tested for Plastic Index. The soils' Plastic Index (PI) is bracketed by the Liquid Limit (LL) and the Plastic Limit (PL). The LL is the moisture content at which the soil will flow as a heavy viscous fluid. The PL is the moisture content at which the soil begins to crumble when rolled into a small thread. These tests are conducted in general accordance with AM D 3. The results are indicated on the Boring Logs at the depth where the sample was obtained. Torvane Shear Tests -- The Torvane test was performed on a precut flat soil sample surface with a calibrated, hand-held spring loaded dial device with thin flanges in a radial array which can be pressed into the soil sample. The vanes are pressed into the soil sample, and the dial face is twisted slowly until the vanes begin to shear the soil. This test gives a direct dial reading of soil shear strength when the sample fails. The test is especially useful for estimating the shear strength of soft cohesive soils. Torvane shear test results are noted on the Boring Logs at the depth of the samples tested. Page 3 of 22

6 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services As part of the testing program, the samples were classified in the laboratory based on visual observation, texture and plasticity. The descriptions of the soils indicated on the Boring Logs are in accordance with the enclosed General Notes and the Unified Soil Classification System. Estimated group symbols according to the Unified Soil Classification System are given on the Boring Logs. A brief description of this classification system is attached to this report. SUBSURFACE CONDITIONS Subsurface conditions encountered during this exploration are indicated on the individual Boring Logs. Based on the results of the borings, subsurface conditions on the project site can be generalized as follows. Asphalt was encountered at the ground surface in borings B-2, B-, B-5, and C-3. The asphalt was about 2 to 3 inches thick. Concrete was encountered beneath the asphalt in borings B-2 and C-3. The concrete was about to 6 inches thick. Wood chips and pea gravel were encountered at the ground surface of boring B- and extended to a depth of approximately 10 inches. Topsoil was encountered at the ground surface in borings B-11, B-, B-13, C-1, C-5, C-, and C-. The topsoil consisted of lean clay with trace amounts of organic matter and extended to depths of about 6 inches to 1 foot below existing grades. Existing fill was encountered in Borings B-, B-5, B-6, B-13, B-1, B-15, C-, and C-. The existing fill consisted of a mix of sand, silt, and crushed limestone, lean clay, sandy lean clay with trace amounts of gravel, and lean to fat clay. The existing fill extended to depths of about 1 to ½ feet below existing grades. Borings C- and C- terminated in the existing fill at a depth of about 5 feet below the existing grade. Page of 22

7 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Alluvium was encountered beneath the fill in borings B-13, B-1, and B-15. These alluvial deposits are likely deposits from the adjacent Duck Creek. The alluvium encountered consisted of lean clay, fat clay, silt, sand, clayey sand, and sandy silt. Borings B-13 through B-15 terminated in the alluvium at a depth of about 25 feet below the existing grades. Loess (wind-blown soil) was encountered at the ground surface in borings B-1, B-3, B-, B-9, B-10, C-, and C-6, beneath the topsoil in borings B-11, C-1, and C-2, beneath the paving section in borings B-2 and C-3, beneath the wood chips and pea gravel in boring B-, and beneath the fill in borings B-, B-5, and B-6. Loess soils have typically not experienced significant overburden pressures beyond the weight of the soil above them. Below the zone of soil affected by seasonal wet/dry cycles (where some preconsolidation by desiccation has occurred), the loess is often near-normally consolidated. The loess soils at the site consisted of silt, lean clay, fat clay, and lean to fat clay. The loess soils extended to depths of about 6 to ½ feet below existing grades. Borings C-1 through C-, and C-6 terminated in the loess at a depth of about 5 feet below the existing grades. Glacial deposits were encountered beneath the loess in borings B-1 through B-11 and beneath the topsoil in borings B- and C-5. The glacial soils were deposited during the advance or retreat of continental glacial ice sheets which once covered this area. These soils are generally termed glacial till. The glacial till soils are more or less unsorted soil deposits consisting of a mixture of sand, silt and clay, with the engineering properties of the soil being controlled by the clay fraction. The glacial till consisted of very stiff to hard sandy lean clay with trace amounts of gravel. Glacial outwash occurs when glacial drift has been sorted and deposited by glacial meltwater streams. This usually deposits layers of well graded sand, and sometimes sand and gravel, but is dependent on the flow velocities of the meltwater streams. Glacial outwash was encountered in many of the borings at the site. These outwash deposits occurred as a sand, silt, clayey sand, and sandy silt. Borings B-1 through B- terminated in the glacial soils at their bottom of boring depths of 25 feet and C-5 terminated in the glacial soils at its bottom of boring depth of 5 feet. Page 5 of 22

8 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Cobbles and boulders were not noted in our borings. However, glacial till soils were encountered at the site and these materials often contain cobbles and boulders. The possibility of their presence should be considered where excavations or grading operations at the site advance into the glacial till soils. The above descriptions provide a general summary of the subsurface conditions encountered. The attached Boring Logs contain detailed information recorded at each boring location. These Boring Logs represent our interpretation of the field logs based on engineering examination of the field samples. The lines designating the interfaces between various strata represent approximate boundaries, and the transition between strata may be gradual. It should be noted that the soil conditions will vary between the boring locations. The generalized Subsurface Soil Profiles (Figures SP-1 through SP-) are presented in the Appendix depicts the relative deposit elevations in the borings. GROUNDWATER CONDITIONS The borings were monitored during drilling operations and several days after completing drilling operations for the presence and level of groundwater. Water levels observed in the borings are noted on the boring logs. During drilling operations, groundwater seepage was observed in borings B-, B-6, B-, B-9, and B-11 through B-15 at depths of 13 to 22 feet below existing grades. Immediately after drilling operations, groundwater accumulation was observed in borings B-, B-6, B-, B-9, and B-11 through B-15 at depths of 13 to 19 feet below existing grades. No groundwater seepage or accumulation was observed in the remaining borings. After a period of approximately 2 hours after the completion of drilling operations, groundwater accumulation was observed in borings B-, B-9, B-11, and B-13 at depths of to 13 feet below existing grades. These groundwater level observations provide an approximate indication of the groundwater conditions existing on this site at the time of drilling operations. Fluctuation of groundwater levels Page 6 of 22

9 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services can occur due to seasonal variations in the amount of rainfall, runoff, surface drainage, subsurface drainage, site topography, irrigation practices, ground cover (pavement or vegetation), and other factors not evident at the time the borings were conducted. Normally, the highest groundwater levels occur in late winter and spring time while the lowest levels occur in late summer and fall time. The fluctuation of the groundwater levels should be considered when developing the design and construction plans for this project. CONUSIONS AND RECOMMENDATIONS Expansive Soil Considerations Moderately expansive lean to fat clay and fat clay soils were encountered in borings B-11, B-, B-13, B-15, C-6, and C-. These expansive soils will experience volume changes with changes in soil moisture content. Therefore, foundations, floor slabs and pavements would be susceptible to swelling pressures that can cause movement, cracking, and structural distress when bearing just above or directly on these soils. To eliminate the risk associated with these expansive soils, it would be necessary to remove the expansive soils at the site and replace them with suitable, compacted and tested non-expansive engineered fill material. However, complete removal or treatment of these soils would be costly and it is our opinion that the following recommendations provide a more practical approach in dealing with the expansive soils encountered at this site. It should be noted that by implementing the following recommendations, the potential movements are reduced to acceptable levels (in our opinion) of 1 inch or less but are not eliminated. If the moderately expansive soils are encountered within the addition area, we recommend that a separation of to 36 inches should be provided between the bottom of floor slabs and the moderately expansive soils. The buffer zone will be dependent on the expansive soils encountered. If expansive soils are encountered within the buffer zone, we recommend that the expansive soils are overexcavated and replaced with to 36 inches of suitable compacted and tested non-expansive select cohesive fill soils or well-graded granular material, with at least 6% passing Page of 22

10 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services the No. 200 sieve. The exact depth of overexcavation will vary throughout the site and should be determined in the field by TEAM services personnel. Further, it is our opinion that the foundations may be constructed directly on the moderately expansive soils provided that they meet the strength and stability requirements discussed elsewhere in this report. The recommended buffer between the bottom of the slab and the expansive soils may include the proposed capillary barrier (detailed in the Floor Slabs section of this report) and/or suitable newly placed and compacted granular or non-expansive cohesive fill as discussed in the Site Preparation section of this report. With the presence of expansive soils at this site, we recommend that continuous wire mesh reinforcement or a regular rebar schedule be considered for the floor slab and that crack control joints be sawn with a regular spacing not greater than about 10 feet. Isolation joints should be provided between the floor slabs and perimeter or interior foundations so that they can move independently without damage. These measures are taken with the intent of allowing floor slabs to deflect somewhat without experiencing large differential movements across slab joints and to channel the cracking of the floor slabs to the crack control joints so that they are not perceived as building distress. Existing Fill Considerations Existing fill was encountered in Borings B-, B-5, B-6, B-13, B-1, B-15, C-, and C-. The existing fill consisted of a mix of sand, silt, and crushed limestone, lean clay, sandy lean clay with trace amounts of gravel, and lean to fat clay. The existing fill extended to depths of about 1 to ½ feet below existing grades. The fill encountered on the south side of the site (Borings B-13, B-1, and B-15) appears to be poorly to well compacted. The poorly compacted portions of the fill encountered on this portion of the site are not suitable for floor slab or foundation support and should be removed and replaced with suitable engineered compacted and tested fill. Page of 22

11 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Man-made fills have an inherently high risk of variability and careful construction inspection will be necessary to assure adequate support performance. In areas where fill is encountered, we recommend that additional testing be conducted at the time of construction to further explore the suitability of the existing fill. Foundations, floor slabs and pavements may be placed on existing fill where testing confirms suitability. If unsuitable soils are encountered these soils should be removed and replaced with engineered compacted and tested fill. It should be noted that the most conservative approach in dealing with unknowns within the existing fill would be to completely remove the fill and replace it with engineered compacted and tested fill. Contract allowances should be made for some remedial work at the site related to subgrade preparation. This may include over-excavation and backfilling of unsuitable soils encountered at subgrade elevation. The amount of such work cannot be defined at this time; therefore, the owner should be informed of these cost variables. Site Preparation Site preparation should begin with the removal of pavement sections and any organic-laden soils, vegetation and any loose, soft, or otherwise unsuitable materials. For planning purposes, we expect a stripping depth of about 6 inches for undisturbed soil areas to remove root-zone soils. The actual depth of stripping may vary and should be determined in the field in consultation with TEAM Services personnel. The site strippings and any near surface soils with organics could be used for landscaping purposes in non-critical areas where support for foundations, floor slabs and pavements is not required. Over-excavation of the expansive soils and existing fill should be performed beneath the structures as discussed in the previous Expansive Soil Considerations and Existing Fill Considerations sections. After stripping, the exposed grade in both cut and fill areas should be proofrolled and inspected by TEAM Services personnel. Proofrolling should be performed at the lowest cut grade, prior to fill placement. Proofrolling should be conducted with a fully loaded tandem axle dump truck having a minimum gross weight of 25 tons. Where proofrolling is not possible due to poor access or excessive disturbance to the existing soils, these soils should be probed and visually Page 9 of 22

12 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services inspected by TEAM Services to determine the suitability of the subgrade. Any unsuitable soils identified during this process should be removed and replaced with suitable engineered compacted and tested fill which meets or exceeds the Class 1 Construction Application requirement in Table A in the following Fill Placement report section. Fill Placement Fill and backfill placed for support of the proposed structure(s) should consist of approved materials which are free of organic matter and debris. Brick, concrete, rocks or other solid pieces with a maximum dimension of 3 inches or larger should not be placed in the newly placed fill sections. We recommend that low-plasticity cohesive soil or granular soil be used for general fill placement. By our definition, low-plasticity cohesive soil would have a liquid limit of 5 or less and a plasticity index of 25 or less. In our opinion, most of the on-site appear to meet these criteria and can be used as newly placed engineered compacted and tested fill; however, the lean to fat clay and fat clay soils do not meet the above criteria and should be utilized only outside the to 36 inch separation below slabs and pavements recommended in the Expansive Soils Considerations section of this report. Any off site potential borrow materials should be evaluated by TEAM Services prior to their use as engineered compacted and tested fill. The following Table A lists recommended minimum compaction requirements for cohesive and cohesionless fill materials for specific applications. For low-plasticity ( and ML) cohesive soils, moisture contents within a range of -2 to +3 percent of the material's optimum moisture content (as determined by Standard Proctor AM D 69) are necessary to achieve the desired fill qualities for general grading and utility backfill while granular soils should be placed within 3 percent of the material s optimum moisture content. Page 10 of 22

13 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Class 1 Class 2 Class 3 TABLE A RECOMMENDED DEGREE OF COMPACTION GUIDELINES Construction Application Subgrade preparation for foundations, pavements and other critical backfill areas Backfill adjacent to structures not supporting other structures or pavements. Minor subsidence possible. Backfill in non-critical areas. Moderate subsidence possible. Standard Proctor (AM D69) Cohesive Soil Standard Proctor (AM D69) Cohesionless Soil Relative Density (AM D253 & D25) Cohesionless Soil 1 95% 9% 0% 90% 93% 5% 5% % 20% 1. Use Relative Density technique (AM D253 & D25) where Standard Proctor technique (AM D69) does not result in a definable maximum dry density and optimum moisture content. The on-site soils can be excavated utilizing conventional excavation equipment. Granular soils can generally be suitably compacted with vibratory compaction equipment. Proper compaction of cohesive soils can be achieved with sheepsfoot or pneumatic type compactors within the above moisture content ranges. The soils should be placed in a maximum loose thickness of inches and at a thickness compatible with the equipment being utilized. Sufficient density tests should be performed on each lift of engineered compacted fill placed to verify that adequate compaction is achieved. Care should be taken to prevent unnecessary disturbance of subgrade soils. Disturbed areas should be removed and replaced with engineered compacted and tested fill in accordance with the recommendations of this report. Upon completion of the filling operation, care should be taken to maintain the subgrade moisture content prior to construction of foundations, floor slabs, and pavements. If the subgrade should become desiccated, frozen or otherwise disturbed, the affected material should be removed or these materials should be scarified, moistened, recompacted and retested prior to concrete placement. As a general guideline, fills which dry to a moisture content less than 2/3 of their optimum moisture Page 11 of 22

14 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services content as determined by the Standard Proctor Test (AM D 69) in their upper 2 inches are candidates for reconditioning as described above. Shallow Spread Foundation Design Foundations for the addition may bear in the existing fill, loess, alluvium, glacial soils, and on newly placed engineered fill required to achieve the desired final grades. In our opinion most of these soils can likely provide adequate support for the proposed buildings. However, portions of the existing fill encountered on the southern portion of the site appear to be poorly compacted. Therefore, these soils should be removed and replaced as previously discussed in the Existing Fill Considerations section. The shallow spread foundations may be designed for a maximum net allowable soil bearing pressure of 2,000 pounds per square foot when bearing on the above-referenced suitable soils. It should be noted that softer soils could be encountered near foundation level near borings B-5 and B-6. If encountered, these unsuitable materials may need to be removed as discussed in the Shallow Foundation Construction section of this report. The net bearing pressure is the pressure in excess of the minimum adjacent overburden pressure at the foundation level. These bearing capacities may be increased by 33% for the total foundation load, which considers transient forces such as wind. We estimate maximum settlements, due to the assumed structural loads, will be less than 1 inch and differential settlement may be on the order of 2/3 of the total settlement. Continuous foundations should be adequately reinforced to limit deflections caused by non-uniform soil support characteristics. All perimeter foundations and foundations in unheated areas should extend at least 2 inches below the lowest adjacent finished grade for frost protection and reduce movements associated with changes in soil moisture content. Interior footings located in permanently frost-free environments should have at least inches of protective embedment below lowest adjacent finished grade. We recommend that isolated spread footings should have a minimum width of 2 inches, continuous formed footings a minimum width of inches and trench footings a minimum width of inches. Page of 22

15 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Where future addition foundations are constructed adjacent to the existing structure s foundations, the proposed foundation bearing elevation should be the same as the existing structure s foundation bearing elevation. If unsuitable soils are present at this depth, then TEAM Services should be retained to develop recommendations to provide adequate foundation support without undermining the existing foundations. Architectural and structural connections should be designed to accommodate the potential differential settlement that may occur between the addition and the existing structure. Where new foundations are placed next to existing foundations, the differential settlements will approach the maximum settlements experienced at the site. Shallow Foundation Construction We recommend that the base of all foundation excavations be observed and tested by the geotechnical engineer prior to placement of concrete. During this process, if loose, soft, organic, or otherwise unsuitable materials are encountered at foundation elevations, we recommend that the foundations extend through the unsuitable soils and bear on undisturbed, suitable soils below or an overexcavation and replacement procedure be performed. The overexcavation and backfill procedure would include removal of these unsuitable materials and replacement with suitable engineered compacted fill soils prepared in accordance with the recommendations in Table A in the Fill Placement section of this report. The following Figure 1 shows a typical cross-sectional view of this overexcavation and backfill procedure. In general, the overexcavation is widened 2/3 of a foot laterally on each side of the foundation per each foot of excavation that is below the foundation bearing elevation. The depth of overexcavation (shown as D in Figure 1) should be determined in consultation with the geotechnical engineer. Backfill materials should be suitable cohesive or granular soil, prepared and compacted in accordance with the recommendations in Table A in the Fill Placement section of this report. Another option would be to remove the unsuitable soils down to suitable soils and replace the excavated area with lean concrete (minimum 50 psi compressive strength), in which case widening of the excavation would not be required. Page 13 of 22

16 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Figure 1. Footing excavations should be kept free of water accumulation to prevent softening of subgrade soils and conducted in a manner which avoids disturbance of soils beneath existing foundations. The silt encountered at the site can be easily disturbed by construction traffic. Therefore, any disturbed soils may require additional removal or compaction prior to concrete placement. Concrete should be placed as soon as possible after excavating to minimize bearing soil disturbance. Should the soils at bearing level become excessively dry, saturated, or otherwise disturbed, the affected soil should be removed prior to placing concrete. Floor Slabs Interior floor slabs can be adequately supported on a minimum of one foot of reworked inorganic non-expansive natural soils, further verified existing fill, or engineered compacted and tested fill required to provide the desired final grades or to replace any unsuitable soils. In cut areas, it is recommended that the building areas be cut to design subgrade level, proofrolled, and the exposed subgrade be scarified to a minimum depth of inches, moisture conditioned (if needed), and recompacted to meet or exceed the Class 1 Construction Application requirement given in Table A in the Fill Placement section of the report. In fill areas, the subgrade should be proofrolled to delineate zones of soft soils present near the surface which may require additional removal or compaction, prior to fill placement. A minimum buffer of to 36 inches should be provided Page 1 of 22

17 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services between the bottom of floor slabs and the moderately expansive lean to fat clay and fat clay soils as discussed in the Expansive Soils Considerations section of this report. To avoid localized slab failures, it is important that interior backfill around foundations and in plumbing trenches be properly compacted. Therefore, all fill materials placed beneath the proposed floor slab are to meet or exceed the Class 1 Construction Application requirement given in Table A. With the presence of expansive soils at this site, we recommend that continuous wire mesh reinforcement be provided for the floor slab and that crack control joints be sawn with a regular spacing not greater than about 10 feet. Isolation joints should be considered between the floor slabs and perimeter or interior foundations so that they can move independently without damage. These measures are taken with the intent of allowing the floor slab to deflect somewhat without experiencing large differential movements across slab joints and to channel the cracking of the floor slabs to the crack control joints so that they are not perceived as building distress. In order to allow successful use of a variety of floor systems, measures to control vapor transmission through the floor slab are recommended where moisture sensitive floor coverings are a possibility. This would include use of a vapor barrier/retarder with a minimum thickness of 10 mils placed between the slab and an underlying capillary barrier material. The vapor barrier/retarder should be strong enough to resist puncturing of capillary barrier materials. We recommend that the capillary barrier consist of clean manufactured sand or crushed limestone (drainable material). The capillary barrier should be at least inches thick and contain less than 6 percent material finer than the U.S. No. 200 sieve. Floor slabs in areas not subject to frost action and floor slabs which are protection from frost action may be designed with a modulus of subgrade reaction of 150 pci when subgrade soils and capillary barriers are constructed in accordance with the recommendations of this report. Page 15 of 22

18 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services Temporary Excavation Support All excavations should comply with the requirements of OSHA 29 CFR, Part 1926, Subpart P, "Excavations and Trenches" and other applicable codes. This document states that excavation safety is the responsibility of the contractor. Reference to this OSHA requirement should be included in the job specifications. Construction Dewatering During construction activities, care should be taken to maintain positive drainage at the site. Based on the boring information obtained at the site, it appears likely that the groundwater will rise above the lowest construction grade during construction. Where excavations extend to near the water table, we recommend that construction groundwater control be established prior to excavating the final 2 feet of soil above the final desired final elevation. In the deeper cut areas, dewatering trenches may be required and should lead to sump pits with pumps or to a free outfall. These dewatering trenches should extend to a minimum elevation of 3 feet below the proposed excavation level and groundwater should be maintained 3 feet or deeper below the lowest excavation level. Groundwater control should be maintained continuously until below grade construction is completed and backfilled sufficiently to withstand the forces which would be induced by the rise in groundwater levels when the dewatering system is no longer in service. If unexpected seepage is encountered or if groundwater control is lost during construction, disturbance of the upper few inches to few feet below grade is likely in some areas of the site. When this occurs, it will be necessary to reestablish groundwater control and remove the disturbed soils. TEAM Services should be consulted regarding the extent of remedial action necessary. Site Drainage Positive site drainage should be maintained along the perimeter of the building and pavements. Final grades should be established to direct runoff away from building foundations. Down spouts, Page of 22

19 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services gutters, and roof drains should discharge away from building perimeters. Site grading should direct surface water away from excavations or completed foundations during construction and after site development is completed. Pavement Subgrade Preparation We expect the soils which will be encountered to support the pavement sections will consist of existing fill, loess, or glacial soils in cut areas and engineered compacted and tested fill required to achieve the desired final grades in fill areas. In order to provide satisfactory pavement performance, it is important that the subgrade support be relatively uniform with no abrupt changes in the subgrade support. Therefore, we recommend that the prepared subgrade depth be at least inches deep after fine grading or trimming and extend 2 feet beyond the edge of the pavements. In cut areas, it is recommended that the pavement subgrade area be cut to design subgrade level and that the exposed subgrade be scarified to a minimum depth of inches, moisture conditioned (if needed), and compacted. In fill areas, the subgrade should be proof-rolled to delineate zones of soft or loose soils present near the surface which may require additional removal or compaction, prior to fill placement. We recommend that reworked existing soils and newly placed engineered compacted non-expansive cohesive soils be placed and compacted in accordance with the Fill Placement section of this report. Suitable engineered compacted cohesive subgrade would provide a design support capability equivalent to a CBR value of 3 or a modulus of subgrade reaction value of 100 pounds per cubic inch. It should be noted that initial subgrade preparation for some soil types, such as the very moist loess soils, may not be suitable under repeated heavy construction vehicle loads and may require stabilization to greater depths or stabilization with fly ash, cement or lime. The use of crushed rock with or without geogrid could also be considered in-lieu of the additional stabilization methods. The subgrade preparation should be completed shortly before paving operations commence and is to be maintained in suitable condition until paved. Damage caused by construction traffic or deterioration due to adverse weather are to be repaired prior to paving. Subgrade compaction, Page 1 of 22

20 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services moisture content and depth should be verified by a TEAM Services representative prior to pavement operations. Where construction traffic is required on the proposed subgrade, the subgrade should be proofrolled immediately prior to pavement placement with a fully loaded, tandem axle dump truck. Areas that yield should be removed and replaced with engineered compacted and tested fill. Surface drainage around the pavement sections is important to long-term pavement performance. Curbs should be backfilled as soon as possible, once adequate pavement strength is achieved. The backfill should be compacted and sloped to prevent water from ponding and infiltrating under the pavement. Water allowed to pond adjacent to the pavement could saturate the subgrade and contribute to premature pavement deterioration. Pavement Subdrains and Drainable Base Course Based on the drainage characteristics of the on-site soils and irrigations practices, we recommend that subsurface drainage be installed in areas of cut of 1 foot or more in natural soils. Depending upon irrigation practices, a shallow subsurface drainage system directly behind the curb may be necessary to intercept this surface water prior to saturating the pavement subgrade. We are available to field evaluate the necessity for subsurface drainage as suspect areas become evident during construction. A drainable granular subbase can improve long-term performance and lower maintenance costs of the pavement sections. Therefore, consideration should be given to implementing a drainage system consisting of a granular subbase connected to subdrains. If subdrains are utilized, the granular subbase beneath the pavement should be relatively free-draining meeting the requirements of IDOT Specification No. 1 (Gradation No. ) or IDOT Specification No. 3 (Gradation No. 1). The granular subbase should be compacted in accordance with the Class 1 Construction Application requirements given in Table A in the Fill Placement section of this report. The free-draining granular subbase should be at least 6 inches thick and be hydraulically connected to subdrains. A subdrain system should consist of a -inch-diameter, perforated, Page of 22

21 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services high-density polyethylene (HDPE), corrugated pipe placed in a trench with a minimum width of 10 inches. The pipe should be centered horizontally within the trenches and the perforations should be sized to prevent infiltration of fine grained soils. The trenches should be backfilled with free draining granular material meeting the criteria of IDOT Specification No. 131 (Gradation No. 29) or IDOT Spec No Cleanouts should be provided on approximate 300 to 00 feet intervals to allow periodic flushing of the drain lines. Subdrains may be located strategically or spaced about 30 to 60 feet on center in parking areas. Subdrains spaced evenly throughout an entire pavement area would provide the best protection and should be located so that the direction of the drains is perpendicular to the down-hill direction of the slopes. In some areas, it may be sufficient to place a single subdrain line at a pavement or drive perimeter, such as to intercept horizontal water flow from a higher elevation, provided that the subdrain lines can continue to flow downhill by gravity to an outfall. The subdrains should be placed approximately 2 inches or deeper below the bottom of the pavement section and sloped to drain to a suitable gravity outfall, such as a storm sewer. Pavement Thicknesses Either flexible (hot mix asphalt, HMA) or rigid pavement (Portland cement concrete, PCC) types could be constructed on the prepared cohesive subgrade as recommended in the previous section. The following Table B summarizes alternate pavement thicknesses for typical lightly-loaded and heavily-loaded paved areas constructed directly on the cohesive subgrade and on a granular base placed on the prepared cohesive subgrade. A more specific pavement evaluation can be provided if traffic volume and loading information is available. The pavement thicknesses in Table B are considered to be typical and would require periodic maintenance. This maintenance would consist of sealing cracks and replacement of isolated distressed areas. Thicker pavement sections would reduce maintenance and increase the pavement service life. Likewise, thinner sections would be expected to have a shorter service life that still may satisfy particular project needs but may require more maintenance. Other criteria which influence pavement service life include surface drainage, subsurface drainage, paving material Page 19 of 22

22 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services quality, and joint design. Construction procedures involving placement, finishing, curing, jointing and weather protection can significantly impact pavement performance. TABLE B TYPICAL PAVEMENT THICKNEES Traffic Volume Rigid: Portland Cement Concrete 1 Full-Depth Type A HMA Flexible: Full-Depth Hot Mix Asphalt 2 Type A Type A over Type B HMA Type B Class I Base Total HMA Thickness Thicknesses below are based on the pavement directly on the prepared cohesive subgrade Lightly-Loaded 3 5" 6" 1.5" 5" 6.5" Heavily-Loaded " " 1.5" ".5" Thicknesses below are based on the pavement on 6 of crushed rock 5 base placed on prepared subgrade Lightly-Loaded Heavily-Loaded ) PCC - Flexural strength of 550 psi (compressive strength of 000 psi). - Structural coefficient (SC) of 0.50/inch. 2) Type A HMA mix with a minimum of 60% crushed aggregate - Structural coefficient of 0./inch. Type B Class I HMA mix with a minimum of 30% crushed aggregate - Structural coefficient of 0.0/inch. 3) Automobile and 1 to 2 trucks average daily traffic. ) Entrances, delivery areas, dumpster areas or other areas of heavier truck traffic (25 trucks or less per day). 5) Crushed rock - Structural coefficient of 0./inch. QUALIFICATION OF REPORT Our evaluation of foundation support conditions has been based on our understanding of the site and project information and the data obtained in our exploration. The general subsurface conditions utilized in our foundation evaluation have been based on interpolation of subsurface Page 20 of 22

23 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services data between the borings. In evaluating the boring data, we have examined previous correlations between soil properties and foundation bearing pressures observed in soil conditions similar to those at your site. The discovery of any site or subsurface conditions during construction which deviate from the data outlined in this exploration should be reported to us for our evaluation. The assessment of site environmental conditions or the presence of pollutants in the soil, rock, and groundwater of the site was beyond the scope of this exploration. Expansive soils were encountered in the borings at this site. These soils experience volume changes in response to soil moisture content changes. These volume changes can cause movement, cracking and other distress for structures supported above them. Measures to help reduce the degree of soil volume change have been discussed. These measures can reduce the risks associated with the potentially expansive soils, but they do not eliminate this risk. Elimination of the risks associated with expansive soils would require removal of the expansive soils and replacement with a more suitable soil type or structurally suspending the planned addition above the expansive soils. Neither of these measures is believed practical. A degree of risk must be accepted to support development at this site. Support of structures on existing fill is discussed in this report. Existing fills are potentially much more inconsistent than natural soil deposits. Support of structures upon existing fills carries with it a degree of risk that unsuitable materials may be buried within the fill and not be detected in the inspection and testing program recommended herein. Unsuitable materials in the fill may experience settlement and cause distress to structures supported on the fill. Elimination of this risk requires removal of the fill. This is costly, and we believe the risks at this site are low enough that the owner should accept this risk and keep the resultant savings. It is recommended that the geotechnical engineer be retained to review the plans and specifications so that comments can be provided regarding the interpretation and implementation of the geotechnical recommendations in the design and specifications. It is further recommended that the geotechnical engineer be retained for testing and observation during the foundation construction phase to help determine that the design requirements are fulfilled. Page 21 of 22

24 Subsurface Exploration Grant Wood Elementary Future Additions - Bettendorf, Iowa Project No November 29, 20 TEAM Services This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No other warranty is provided. In the event that any changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and the conclusions of this report modified or verified in writing by the geotechnical engineer. Page 22 of 22

25 N SITE TEAM Services, Inc. Grant Wood Elementary Project No SE 6 th Street Des Moines, IA Bettendorf, Iowa SITE LOCATION MAP November 30, 20

26 B- Not to Scale N Approximate boring location TEAM Services, Inc. Grant Wood Elementary Project No SE 6 th Street Des Moines, IA Bettendorf, Iowa BORING PLAN November 30, 20

27 BORING LOG No. B-1 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- SILT, trace organics, light olive brown, stiff -- trace organics upper 10" USCS SYMBOL ML DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * * * -- becomes gray after ' *.5 Glacial Till -- Sandy lean AY, trace gravel, strong brown, very stiff * 20.0 Glacial Outwash -- Clayey SAND, yellowish brown SC * Torvane = 200 psf Glacial Outwash -- Sandy SILT, yellowish brown, loose Bottom of Boring SM geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

28 BORING LOG No. B-2 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 653. Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Asphalt (2" +/-) Concrete (" +/-) Loess -- SILT, light olive brown, very stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER 1 SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) 11 MOIURE, % 1.9 DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) 5000* OTHER * *.0 Glacial Till -- Sandy lean AY, trace gravel, strong brown, very stiff * -- becomes olive brown, hard after 1.5' * 25.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

29 BORING LOG No. B-3 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- SILT, light olive brown, very stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * * * *.5 Glacial Till -- Sandy lean AY, trace gravel, strong brown, very stiff 60.6 Cl * 1.5 Glacial Ouwash -- Clayey SAND, yellowish brown, medium dense SC 20.0 Glacial Outwash -- Fine to medium SAND, yellowish brown, medium dense SP * Glacial Till -- Sandy lean AY, trace gravel, light olive brown, stiff Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

30 BORING LOG No. B- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 63.3 Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Asphalt (2 1/2" +/-) Fill -- Mix of SAND, SILT, and crushed LIMEONE Loess -- SILT, light olive brown, stiff USCS SYMBOL FILL ML DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY 13 SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) 000* OTHER * -- becomes gray, very stiff after 6' * Glacial Outwash -- Clayey SAND, dark yellowish brown, medium dense 631. SC Glacial Outwash -- SILT, dark yellowish brown, stiff ML * Glacial Outwash -- Clayey SAND, yellowish brown, medium dense Bottom of Boring SC geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 13' Ft. While Drilling Boring Completed: 11//20 1' Ft. After Drilling Rig: ATV Foreman: DC 13' Ft. 1.5 hrs Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

31 BORING LOG No. B-5 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 63. Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Asphalt (3") Fill -- Sandy lean AY, trace gravel, olive brown Loess -- SILT, light olive brown, soft USCS SYMBOL FILL ML DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) 1000* OTHER 6.0 Glacial Till -- Sandy lean AY, trace gravel, olive brown, very stiff * 5000* Torvane = 350 psf -- becomes strong brown and gray after.5' *.5 Glacial Outwash -- Clayey SAND, trace gravel, brown, loose SC Glacial Outwash -- SILT, light olive brown, very stiff ML * -- becomes olive brown, hard after 22.5' 25.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

32 BORING LOG No. B-6 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 6.6 Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Fill -- Lean AY, trace organics, olive brown Loess -- SILT, light olive brown 63.5 USCS SYMBOL FILL ML DEPTH (ft.) 0 NUMBER 1 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % 2. DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * * 6.0 Glacial Till -- Lean AY, olive brown, very stiff *.5 Glacial Till -- Sandy lean AY, trace gravel, strong brown and gray, very stiff *.5 Glacial Outwash -- Clayey SAND, yellowish brown, medium dense SC Glacial Outwash -- SILT, olive brown very stiff 62.0 ML * 25.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 22' Ft. While Drilling Boring Completed: 11/9/20 19' Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

33 BORING LOG No. B- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- SILT, olive brown, stiff to very stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * * *.5 Glacial Till -- Sandy lean AY, trace gravel, strong brown, hard * 1.5 Glacial Outwash -- SILT, light olive brown, very stiff 62. ML * 21.5 Glacial Till -- Lean AY, olive brown, hard Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 None Ft. While Drilling Boring Completed: 11/9/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

34 BORING LOG No. B- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 61. Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Wood Chips (" +/-) Pea Gravel (6" +/-) Loess -- SILT, light olive brown, stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * 3.5 Loess -- Lean AY, light olive brown, stiff * 6.0 Glacial Till -- Sandy lean AY, trace gravel, strong brown, very stiff * -- becomes hard after.5' *.5 Glacial Outwash -- Clayey SAND, yellowish brown, medium dense 629. SC * * Torvane = Bottom of Boring geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 20' Ft. While Drilling Boring Completed: 11/10/20 1' Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

35 BORING LOG No. B-9 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- Lean AY, light olive brown, very stiff USCS SYMBOL DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER becomes dark gray after 6' * *.5 Glacial Till -- Lean AY, trace sand, gray, very stiff *.5 Glacial Outwash -- SILT, light olive brown, very soft ML * 1.5 Glacial Outwash -- SILT, light olive brown, very stiff ML * Torvane = 200* Glacial Till -- Lean AY, dark gray, hard Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 19' Ft. While Drilling Boring Completed: 11/9/20 ' Ft. After Drilling Rig: ATV Foreman: DC ' Ft. 2 hrs Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

36 BORING LOG No. B-10 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- Lean AY, strong brown USCS SYMBOL DEPTH (ft.) 0 NUMBER 1 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % 23 DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * * 6.0 Glacial Outwash -- Clayey SAND, yellowish brown, strong brown SC Glacial Outwash -- Fine to medium SAND, gray, medium SP Glacial Outwash -- SILT, gray, stiff ML * 1.5 Glacial Till -- Lean AY, dark gray, hard * 25.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 None Ft. While Drilling Boring Completed: 11/9/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

37 BORING LOG No. B-11 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Topsoil -- Lean AY, trace organics, dark olive brown Loess -- Lean to Fat AY, very dark brown and gray, very stiff USCS SYMBOL - CH DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) 10 MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) 6000* OTHER 3.5 Loess -- Lean AY, very dark brown and gray, stiff * -- becomes gray after 6' *.5 Loess -- SILT, dark gray, stiff 6.6 ML * * * Glacial Outwash -- Silty coarse SAND, trace gravel, brownish yellow, medium dense Bottom of Boring SM geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 21' Ft. While Drilling Boring Completed: 11/9/20 1' Ft. After Drilling Rig: ATV Foreman: DC ' Ft. 2 hrs Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

38 BORING LOG No. B- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Topsoil -- Lean AY, trace organics, dark olive brown Glacial Till -- Fat AY, trace sand and gravel, light olive brown, very stiff 621. USCS SYMBOL CH DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) 9 TES UNCONFINED RENGTH (PSF) 000* OTHER.0 Glacial Till -- Sandy lean AY, trace gravel, yelloiwsh brown, very stiff * -- becomes stiff after 6' * *.5 Glacial Outwash -- SILT, olive brown, stiff ML * -- becomes gray after ' 20.0 Glacial Outwash -- Fine SAND, dark gray, medium dense 602. SP * 25.0 Bottom of Boring geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 20' Ft. While Drilling Boring Completed: 11/9/20 ' Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

39 BORING LOG No. B-13 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 61.1 Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Topsoil -- Lean AY, trace organics, olive brown Fill -- Lean to fat AY, light olive brown 6. USCS SYMBOL Fill Fill DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) 10 MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER 3.5 Fill -- Lean AY, light olive brown FILL Alluvium -- Lean AY, very dark brown, very stiff Alluvium -- Lean AY, olive brown, blueish gray, and very dark brown, very stiff Alluvium -- SILT, gray, stiff ML * Alluvium -- Fine to medium SAND, yellowish brown medium dense SP Alluvium -- Fine SAND, dark gray, medium dense Bottom of Boring SP geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/ ' Ft. While Drilling Boring Completed: 11/9/20 13' Ft. After Drilling Rig: ATV Foreman: DC ' Ft. hrs Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

40 BORING LOG No. B-1 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 6.5 Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Fill -- Lean AY, trace organics, olive brown Fill -- Lean AY, light olive brown USCS SYMBOL Fill Fill DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER Alluvium -- Lean AY, olive brown and dark gray, very stiff * -- becomes dark gray after ' Alluvium -- Fine to coarse SAND, yellowish brown, medium SW Alluvium -- Lean AY, gray, stiff Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/9/20 ' Ft. While Drilling Boring Completed: 11/9/20 ' Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

41 BORING LOG No. B-15 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 6. Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Fill -- Lean AY, light olive brown USCS SYMBOL Fill DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER becomes stiff after ' Alluvium -- Fat AY, very dark brown, very stiff 60. CH *.5 Alluvium -- Clayey SAND, gray, medium dense 60. SC 15.0 Alluvium -- Sandy SILT, gray SM Alluvium -- Clayey SAND, medium dense 599. SC Alluvium -- Medium to coarse SAND, olive brown, medium dense 59.9 SP 25.0 Bottom of Boring geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 15' Ft. While Drilling Boring Completed: 11/10/20 13' Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

42 BORING LOG No. C-1 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS 0.5 DESCRIPTION Topsoil -- Lean AY, trace organics, olive brown Loess -- SILT, light olive brown, stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER 1 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % 21.1 DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * 5.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

43 BORING LOG No. C-2 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION 0.5 Topsoil -- Lean AY, trace organics, olive brown Loess -- SILT, light olive brown, very stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) 6000* OTHER * Bottom of Boring 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

44 BORING LOG No. C-3 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Asphalt (2" +/-) Concrete (6" +/-) Loess -- SILT, light olive brown, stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * 5.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 None Ft. While Drilling Boring Completed: 11/10/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

45 BORING LOG No. C- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- SILT, light olive brown, stiff USCS SYMBOL ML DEPTH (ft.) 0 NUMBER 1 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % 1.5 DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * 5.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11//20 None Ft. While Drilling Boring Completed: 11//20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

46 BORING LOG No. C-5 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Topsoil -- Lean AY, trace organics, olive brown Glacial Till -- Sandy lean AY, trace gravel, strong brown, very stiff USCS SYMBOL DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) 10 TES UNCONFINED RENGTH (PSF) 6000* OTHER Glacial Outwash -- Clayey SAND, strong brown Bottom of Boring SC * 5500* 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 None Ft. While Drilling Boring Completed: 11/10/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

47 BORING LOG No. C-6 Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): Site Datum: NAVD - IARTN Drilling Method: HS DESCRIPTION Loess -- Fat AY, olive brown and gray, very stiff USCS SYMBOL CH DEPTH (ft.) 0 NUMBER SAMPLES TYPE RECOVERY SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER * 5.0 Bottom of Boring * 1-00.geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 None Ft. While Drilling Boring Completed: 11/10/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

48 BORING LOG No. C- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 6. Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Topsoil -- Lean AY, trace organics, olive brown Fill -- Lean to fat AY, olive brown, very stiff 61.9 USCS SYMBOL Fill DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY 3 SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER 5.0 Bottom of Boring geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 None Ft. While Drilling Boring Completed: 11/10/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

49 BORING LOG No. C- Page 1 of 1 PROJECT Grant Wood Elementary SITE Bettendorf, IA GRAPHIC LOG Approx. Surface Elevation (ft): 6.21 Site Datum: NAVD - IARTN Drilling Method: HS 1.0 DESCRIPTION Topsoil -- Lean AY, trace organics, olive brown Fill -- Lean AY, olive brown, very stiff USCS SYMBOL Fill DEPTH (ft.) 0 NUMBER 1 2 SAMPLES TYPE AS RECOVERY 5 SPT - N (BLOWS / FT.) MOIURE, % DRY DENSITY (PCF) TES UNCONFINED RENGTH (PSF) OTHER 5.0 Bottom of Boring geo TSBORA.fdt 5/19/20 Notes: * Calibrated hand penetrometer Hammer Type: Manual Water Level: Boring Started: 11/10/20 None Ft. While Drilling Boring Completed: 11/10/20 None Ft. After Drilling Rig: ATV Foreman: DC Ft. Approved: SB Job #: 1-00 THE RATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES; IN-SITU, THE TRANSITION MAY BE GRADUAL.

50 N/Qu 3500* 3500* C-1 MC/DD N/Qu 6000* * C-2 N/Qu MC/DD * * * 000* B-1 MC/DD N/Qu * 500* 6 000* B-2 MC/DD N/Qu * 5000* * 000* B-3 MC/DD N/Qu 3500* * C-3 MC/DD * * * Elevation in Feet * * * * * Elevation in Feet Vertical Scale: 1" = 10' Shelby Tube Split Spoon Topsoil Silty sand Water Level Readings: C-1 C-2 B-1 B-2 B-3 C-3 Silt Sandy lean clay Clayey sand Asphalt Concrete Poorly graded sand Grant Wood Elementary Bettendorf, IA TEAM No During drilling MC - Moisture Content (%) DD - Dry Density (pcf) At completion of drilling N Qu Extended reading - SPT - Blows per Foot - Unconfined Compression Strength or Pocket Penetrometer* (psf) SUBSURFACE SOIL PROFILE FIGURE SP-1

51 N/Qu * * 500* * B- MC/DD N/Qu 1500* * 9 000* 000* B-6 MC/DD N/Qu 1000* 1000* * 6500* 6 B-5 MC/DD N/Qu * 3500* * * B- MC/DD N/Qu 000* * 2500* B- MC/DD N/Qu 3500* 3000* C- MC/DD Elevation in Feet * 5 000* * * * * * 500* * Elevation in Feet Vertical Scale: 1" = 10' Shelby Tube Split Spoon Silt Clayey sand Fine gravel Water Level Readings: B- B-6 B-5 B- B- C- Sandy lean clay Lean clay Fill Asphalt EXTRA: alternating dot-dash pattern During drilling MC - Moisture Content (%) DD - Dry Density (pcf) At completion of drilling N Qu Extended reading - SPT - Blows per Foot - Unconfined Compression Strength or Pocket Penetrometer* (psf) Grant Wood Elementary Bettendorf, IA TEAM No SUBSURFACE SOIL PROFILE FIGURE SP-2

52 N/Qu B-10 MC/DD * 22.6 N/Qu B-9 MC/DD * * * 21. Elevation in Feet * 000* 9000* N/Qu 000* * 3000* * 2000* B- MC/DD * 3 500* 5000* * N/Qu 2 500* B-1 MC/DD N/Qu * 3000* * * * B-11 MC/DD N/Qu * B-13 MC/DD 2.N/Qu * 21.6 B-15 MC/DD Elevation in Feet * * * B-10 B- B-9 B-11 Vertical Scale: 1" = 10' Shelby Tube Split Spoon Lean clay Clayey sand Poorly graded sand Silt Topsoil Lean to fat clay Sandy lean clay Fill Well graded sand Silty sand Lean to fat clay fill Fat clay Water Level Readings: During drilling MC - Moisture Content (%) DD - Dry Density (pcf) At completion of drilling N Qu Extended reading - SPT - Blows per Foot - Unconfined Compression Strength or Pocket Penetrometer* (psf) B-1 B-13 B-15 Grant Wood Elementary Bettendorf, IA TEAM No SUBSURFACE SOIL PROFILE FIGURE SP-3

53 N/Qu C- MC/DD * 3000* N/Qu C-5 MC/DD * 500* 5500* Elevation in Feet 620 N/Qu C- MC/DD.6 N/Qu 6500* 000* C-6 MC/DD Elevation in Feet N/Qu C- MC/DD C- Vertical Scale: 1" = 10' Shelby Tube Split Spoon C-6 C-5 Topsoil Fill Lean to fat clay fill Fat clay Sandy lean clay Clayey sand Silt Water Level Readings: During drilling MC - Moisture Content (%) DD - Dry Density (pcf) At completion of drilling N Qu Extended reading - SPT - Blows per Foot - Unconfined Compression Strength or Pocket Penetrometer* (psf) C- C- Grant Wood Elementary Bettendorf, IA TEAM No SUBSURFACE SOIL PROFILE

54 ATTERBERG LIMITS TE REPORT 60 Dashed line indicates the approximate upper limit boundary for natural soils PLAICITY INDEX or OL CH or OH 10 -ML ML or OL MH or OH LIQUID LIMIT MATERIAL DESCRIPTION LL PL PI %<#0 %<#200 USCS Glacial Till -- Fat AY, trace sand and gravel, light olive brown, very stiff Fill -- Lean AY, light olive brown Project No Client: Remarks: Project: Grant Wood Elementary Source of Sample: B- Depth: 1.5 Sample Number: 2 Source of Sample: B-13 Depth: Sample Number: 3 Figure A-1 Tested By: NG Checked By: CAS

55 UNIFIED SOIL AIFICATION SYEM TEAM Services Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Group Symbol Soil Classification Group Name B Coarse-Grained Soils More than 50% retained on No. 200 sieve Fine-Grained Soils 50% or more passes the No. 200 sieve Gravels More than 50% of coarse fraction retained on No. sieve Sands 50% or more of coarse fraction passes No. sieve Silts and Clays Liquid limit less than 50 Clean Gravels Cu > and 1 < Cc < 3 E GW Well-graded gravel F Less than 5% fines C Cu < and/or 1 > Cc > 3 E GP Poorly graded gravel F Gravels with Fines Fines classify as ML or MH GM Silty gravel F, G, H More than % fines C Fines classify as or MH GC F, G, H Clayey gravel Clean Sands Cu < 6 and 1 < Cc < 3 E SW Well-graded sand I Less than 5% fines E Cu < 6 and/or 1 > Cc > 3 E SP Poorly graded sand I Sands with Fines Fines classify as ML or MH SM Silty sand G, H, I More than % fines D Fines classify as or CH SC G, H, I Clayey sand inorganic Pl > and plots on or above A line J K, L, M Lean clay Pl < or plots below A line J K, L, M ML Silt K, L, M, N organic Liquid limit oven dried < 0.5 OL Organic clay Liquid limit not dried K, L, M, O Organic silt Silts and Clays Liquid limit 50 or more K, L, M inorganic Pl plots on or above A line CH Fat clay K, L, M Pl plots below A line MH Elastic silt K, L, M, P organic Liquid limit oven dried < 0.5 OH Organic clay Liquid limit not dried K, L, M, Q Organic silt Highly Organic Soils Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-in. (5-mm) sieve. B If field sample contained cobbles or boulders, or both, add with cobbles or boulders, or both to group name. C Gravels with 5 to % fines require dual symbols: GW-GM well-graded gravel with silt GW-GC well-graded gravel with clay GP-GM poorly graded gravel with silt GP-GC poorly graded gravel with clay D Sands with 5 to % fines require dual symbols: SW-SM well-graded sand with silt SW-SC well-graded sand with clay SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay For classification of fine-grained soils and fine grained fraction of coarsegrained soils. Equation of A Line: Horizontal at Pl = to LL then Pl = 0.3 (LL-20) E Cu = D 60 /D 10 Cc = (D 30 ) 2 D 10 x D 60 F If soil contains > 15% sand, add with sand to group name. G If fines classify as -ML, use dual symbol GC-GM, or SC-SM. H If fines are organic, add with organic fines to group name. I If soil contains > 15% gravel, add with gravel to group name. J If Atterberg limits plots in shaded area, soil is a -ML, silty clay. K If soil contains 15 to 29% plus No. 200, add with sand or with gravel, whichever is predominant. L If soil contains > 30% plus No. 200 predominantly sand, add sandy to group name. M If soil contains > 30% plus No. 200, predominantly gravel, add gravelly to group name. N Pl > and plots on or above A line. O Pl < or plots below A line. P Pl plots on or above A line. Q Pl plots below A line.

56 GENERAL NOTES SOIL and ROCK TYPES PA HA DB AS HS WS RB BS DC WB AR DRILLING & SAMPLING SYMBOLS Split Spoon - 1 1/2" I.D., 2" O.D., unless otherwise noted Thin-Walled Tube - 3" O.D., unless otherwise noted Power Auger Hand Auger Diamond Bit - ", N, B Auger Sample Hollow Stem Auger Wash Sample Rock Bit Bulk Sample Dutch Cone Wash Bore Air Rotary Consistency CONSIENCY OF FINE-GRAINED SOILS (major portion passing No. 200 sieve) Very Soft Soft Medium Stiff Very Stiff Hard Very Hard Unconfined Compressive Strength, Qu, psf < ,000 1,001-2,000 2,001 -,000,001 -,000,001 -,000 > -,000 N-Blows/ft* (Approx. Correlation) RELATIVE DENSITY OF COARSE-GRAINED SOILS Relative Density N-Blows/ft. * Very Loose Loose Medium Dense Dense Very Dense Extremely Dense * Standard "N" Penetration Blows per foot of a 10 pound hammer falling 30 inches on a 2-inch OD split spoon, except where noted. RELATIVE PROPORTIONS OF SAND AND GRAVEL Descriptive Term(s) (of components also present in sample) Trace With Modifier Percent of Dry Weight < > 30 RELATIVE PROPORTIONS OF FINES Descriptive Term(s) (of components also present in sample) Trace With Modifier WATER LEVELS: WD = While Drilling AD = After Drilling Depth groundwater first encountered during drilling Percent of Dry Weight < > Groundwater level after 2 hours (unless otherwise noted, i.e. "AD" -- after drilling) Major Component of Sample Boulders Cobbles Gravel Sand Silt or Clay GRAIN SIZE TERMINOLOGY Size Range Over in. (300 mm) in. to 3 in. (300 mm to.5 mm) 3 in. to # sieve (5 mm to.5 mm) # to #200 sieve (.5 mm to 0.05 mm) Passing #200 sieve (0.05 mm) TERMS DESCRIBING SOIL RUCTURE Parting: paper thin in size Fissured: containing shrinkage cracks, frequently filled with Seam: 1/" to 3" in thickness fine sand or silt, usually more or less vertical. Layer: greater than 3" in thickness Interbedded: composed of alternate layers of different soil types. Ferrous: containing appreciable quantities of iron Laminated: composed of thin layers of varying color and texture. Well-Graded: Poorly-Graded: having wide range in grain size and substantial amounts of all intermediate sizes. predominately one grain size or having a range of sizes with some intermediate sizes missing. Slickensided: NOTE: having inclined planes of weakness that are slick and glossy in appearance. Clays possessing slickensided or fissured structure may exhibit lower unconfined strength than indicated above. Consistency of such soil is interpreted using the unconfined strength along with pocket penetrometer results.