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HomeMy WebLinkAboutGeotechnical Exploration & Review 06.0807 REPORT OF GEOTECHNICAL EXPLORATION AND REVIEW Proposed Shepherd's Path Senior Housing Prior Lake,Minnesota • AET#01-02817 Date: March 27,2006 Prepared for: Shepherd of the Lake Lutheran Church 13760 McKenna Road Northwest Prior Lake,MN 55379 CONSULTANTS AMERICAN •ENVIRONMENTAL A ENGINEERING •GEOTECHNICAL •MATERIALS TESTING, INC. •FORENSICS March 27,2006 Shepherd of the Lake Lutheran Church 13760 McKenna Road Northwest Prior Lake,MN 55379 Attn: Mr. Kermit Mahlum RE: Geotechnical Exploration and Review Proposed Shepherd's Path Senior Housing Prior Lake, Minnesota AET#01-02817 Dear Mr. Mahlum: This report presents the results of a subsurface exploration program and geotechnical engineering review for the referenced project. We are submitting three (3) copies of the report to you, and one(1)copy to Pope Architects. Please call if you have any questions about the report. I can also be contacted for arranging construction observation and testing services during the earthwork phase. Sincerely, American Engineering Testing,Inc. 004,lZ Jay Brekke,P.E. Project Engineer Phone: (651) 789-4645 Fax: (651) 659-1347 jbrekke@a,amengtest.com cc: Mr. Dan Weatherman—Pope Architects JB/jmg This document shall not be reproduced,except in full,without written approval of American Engineering Testing,Inc. 550 Cleveland Avenue North•St.Paul,MN 55114 Phone 651-659-9001 .Toll Free 800-972-6364•Fax 651-659-1379•www.amengtest.com Offices throughout Florida,Minnesota,South Dakota&Wisconsin AN AFFIRMATIVE ACTION AND EQUAL OPPORTUNITY EMPLOYER TABLE OF CONTENTS SUMMARY 1 Purpose 1 Scope 1 Findings 1 Recommendations 1 INTRODUCTION 2 Scope of Services 2 PROJECT INFORMATION 3 Foundation Design Assumptions 3 SITE CONDITIONS 3 Surface Observations 3 Subsurface Soils/Geology 4 Water Level Measurements 4 GEOTECHNICAL CONSIDERATIONS 5 Review of Soil Properties 5 RECOMMENDATIONS 6 Building Grading 6 Foundations 9 Floor Slab 9 Sidewalk/Exterior Building Backfilling 9 Pavement 10 CONSTRUCTION CONSIDERATIONS 12 Potential Difficulties 12 Excavation Sidesloping/Retention 13 Observation and Testing 13 _ SUBSURFACE EXPLORATION 13 General 13 Drilling Methods 13 Sampling Methods 13 Classification Methods 14 Water Level Measurements 14 Sample Storage 15 LABORATORY TESTING 15 LIMITATIONS 15 STANDARD OF CARE 16 SIGNATURES 16 TABLE OF CONTENTS STANDARD DATA SHEETS Excavation and Refilling for Structural Support Basement/Retaining Wall Backfill and Water Control Floor Slab Moisture/Vapor Protection Freezing Weather Effects on Building Construction Bituminous Pavement Subgrade Preparation and Design APPENDIX A Figure 1 -Boring Locations Soil Boring Logs Boring Log Notes Unified Soil Classification System GEOTECHNICAL EXPLORATION AND REVIEW FOR SHEPHERD'S PATH SENIOR HOUSING PRIOR LAKE, MINNESOTA AET #01-02817 SUMMARY Purpose Shepherd of the Lake Lutheran Church is planning to construct a senior housing building east of their existing church. The new building will be connected by a walkway to the existing church. The purpose of our work on this project is to explore subsurface conditions and provide geotechnical engineering recommendations to assist you and the project team in planning, design and construction. Scope To accomplish the above purpose, you authorized our firm to drill four additional test borings at the site (to supplement past borings performed in the area), conduct laboratory testing and prepare this geotechnical engineering report. Findings The site geology is predominantly glacially-deposited till consisting of clay and clayey sand, although past borings indicate some alluvial deposition is also present. Fill is present at some areas, as deep as about 9'below existing grade. Recommendations These recommendations are condensed for your convenience. Study our entire report for detailed recommendations. • General grading for building support should include excavating topsoil, fill and soft and/or dark colored fine alluvial soils. Under footings, additional excavation should be carried out where soft to medium consistency alluvial clays are present within 5' of the footing grade. The on-site non-organic clays can be reused as structural fill provided they can be sufficiently moisture conditioned to attain compaction. This conditioning process can be time consuming and labor intensive, and will require favorable weather. • After proper site preparation, the building can be supported on conventional spread foundations,designed for an allowable soil bearing pressure of 3,000 psf. • To prepare pavement subgrades, existing topsoil should be stripped, followed by additionally subcutting any unstable clay soils within the upper 3' subgrade zone. The on-site clayey soils are slow-draining and frost-susceptible; therefore, we recommend placing a 1'thick sand subbase layer over the on-site clayey soils. AET Job#01-02817 Page 2 of 16 INTRODUCTION This report presents the results of a subsurface exploration program and geotechnical engineering review for the proposed Shepherd's Path Senior Housing in Prior Lake,Minnesota. To protect you,American Engineering Testing,Inc.(AET),and the public,we authorize use of opinions and recommendations in this report only by you and your project team for this specific project.Contact us if other uses are intended.Even though this report is not intended to provide sufficient information to accurately determine quantities and location of particular materials,we recommend that your potential contractors be advised of the report availability. Existing Geotechnical Information We drilled 16 soil borings on this site for the original church construction in November 2000. The findings of our borings are detailed in our report dated December 1, 2000 (AET Project No. 01-00590). Most of the borings we conducted at the time were located west of the currently proposed construction. Borings 9, 10, 11, and 12 are within the area of the proposed new construction, and we have included copies of these boring logs in this report. We also provided the construction testing for the construction of the existing church. Scope of Services AET's work on this project was done in accordance with our proposal dated February 3, 2006, which you authorized on February 7, 2006. The authorized scope of services for this project consists of the following: • Four(4)standard penetration test borings to depths of 21'. These borings are numbered 17 through 20, following the numbering sequence of our borings in 2000. • Soil laboratory testing(water content). • Geotechnical engineering analysis based on the above and preparation of this report. The scope of our work is intended for geotechnical purposes only. This scope is not intended to explore for the presence or extent of environmental contamination at the site or provide opinions regarding the status of the site relative to"wetland"definitions. AET Job#01-02817 Page 3 of 16 PROJECT INFORMATION The proposed senior housing building will be a four-story structure with one level of underground parking, and will be connected by a walkway to the existing church. We have not been provided with construction details, but assume the structure will be of cast-in-place or masonry bearing walls below grade, with precast plank for the first floor and wood frame construction above. Mr. Gary Weimueller, P.E., of Structural Design Associates, estimates wall loads of 7 to 9 kips per linear foot,and column loads of 300 to 435 kips. The lowest finished floor elevation (parking level) of the building has been set at elevation 897.4'. Existing grades in the building footprint range from about 892' to 909'. We anticipate that the live floor loads in this building would not exceed 200 pounds per square foot. Bituminous paved parking and drive areas will be constructed to the north and east of the new building. We anticipate that most of the traffic will be relatively light (automobiles and passenger-type trucks). Some areas may also receive additional occasional heavier vehicles such as waste collection trucks and delivery trucks. Based on the grading plans, it appears that McKenna Road will be reconfigured and reconstructed; our report does not address this public street. Foundation Design Assumptions Our foundation design assumptions include a minimum factor of safety of 3 with respect to localized shear or base failure of the foundations.We assume the structure will be able to tolerate total settlements of up to 1", and differential settlements over a 30'distance of up to %Z'. The presented project information represents our understanding of the proposed construction. This information is an integral part of our engineering review.It is important that you contact us if there are changes from that described so that we can evaluate whether changes in our recommendations are appropriate. SITE CONDITIONS Surface Observations The site is located along McKenna Road Northwest in Prior Lake, Minnesota. At the time of our exploration, the northern portion of the site was a bituminous-paved parking lot. The remainder of the site was mostly grass-covered or grass and weed covered with small trees/brush. There AET Job#01-02817 Page 4 of 16 was an existing wetland southeast of the proposed building location. According to the site plan provided to us,this wetland had a water elevation of 889.3'on November 6, 2004. Subsurface Soils/Geology Logs of the test borings are included in Appendix A. The logs contain information concerning soil layering, soil classification,, geologic description and moisture. Relative density, or consistency is also noted,which is based on the standard penetration resistance (N-value). We found topsoil or fill to about 1.5'to 9'below grade in each of our four recent borings and four previous borings (9 through 12). Since grading has taken place since the original four borings were drilled, there may be greater fill thicknesses at these locations (such as at boring 9 which appears to have been filled approximately 10'since the boring was done). Underlying the existing topsoil or fill,the site is predominantly glacially-deposited till,classified as sandy lean clay and clayey sand, usually containing a little gravel. There are occasional sand layers within the till. In some areas, the till is overlain by or interbedded with alluvium, which refers to soils deposited by water. The alluvium often consists of lean clay with varying amounts of sand. The boring logs only indicate the subsurface conditions at the sampled locations. Variations often occur between and beyond borings. A lower wetland area is present to the south of the proposed easterly wing of the building(south of past boring 11). Although the building does not lie directly over the wetland, a low elevation swale projects northwesterly from the wetland into the building area. AET did not select the boring locations, and there is an absence of soils data in this lower area. Past borings 11 and 12 lie to the northeast and northwest, respectively. Both of those borings are uphill from the lower area, and both suggest a marginal profile with interbedded alluvial soils to be present(these areas are some of the more limiting soils on this site). Therefore,it will be important to gain additional subsurface information in this area,whether before construction or during construction. Water Level Measurements The boreholes were probed for the presence of groundwater and water level measurements were taken. The measurements are recorded on the boring logs. A discussion of the water level AET Job#01-02817 Page 5 of 16 measurement methods is presented in the SUBSURFACE EXPLORATION section of this report. Groundwater was not encountered in any of our recent borings; groundwater was encountered at about 10'below grade in boring 12, drilled in 2000. Most of the on-site soils are slow-draining cohesive soils, and an extended period of time would be needed for groundwater levels to stabilize within an open borehole. Therefore, you should anticipate that the actual hydrostatic groundwater level is shallower than found in our borings. Additionally, higher groundwater levels are generally found in the spring and summer than in the fall or winter, when our borings were drilled. The groundwater levels will vary in elevation seasonally and annually, depending on seasonal and yearly rainfall, as well as other factors. In our opinion, the hydrostatic groundwater level on the site will be found at or above the wetland, which is an expression of groundwater. You should anticipate hydrostatic groundwater at or above about elevation 890. GEOTECHNICAL CONSIDERATIONS The following geotechnical considerations are the basis for the recommendations presented later in this report. Review of Soil Properties Strength/Compressibility The existing fill soils are undocumented, and were not placed with the intent of supporting future structures, and are unsuitable for structural support. Topsoil layers are also organic and are unsuitable. The naturally-occurring, non-organic sandy lean clay and clayey sand are generally suitable for support of the proposed structure, however, relatively soft or wet clays (N-values of 5 bpf or less) are relatively weak, and should be removed where present within 5' of footing grade. AET Job#01-02817 Page 6 of 16 Drainage Properties The predominant cohesive soil types encountered on this site are moderately slow to slow- draining materials. Some occasional more permeable lenses/layers of granular soils are also present on the site. Frost Susceptibility The site soils are judged to be moderately frost susceptible. RECOMMENDATIONS Building Grading Excavation To prepare the building area for foundation and floor slab support, we recommend stripping/subcutting the existing topsoil and fill, and any obviously soft, wet or disturbed soils. We recommend additionally removing any soft to medium consistency clays, with an N-value of 5 bpf or less, which are present (vertically) within 5' below footings. The excavation bottom should be laterally oversized at least 1'horizontally beyond the edge of footings, for each foot of fill required below the bottom of footings,as measured at the base of the subcut. If the site is mass-graded and specific footing locations/elevations are not staked during grading, removal of these soft to medium consistency clays would be needed throughout the entire building area; however, if footing locations are accurately staked and elevations determined, this additional soft to medium consistency clay removal can then be limited to the footing areas only. The following table shows the estimated elevation of the excavations to remove existing topsoil, fill and soft to medium consistency clays at our boring locations. The actual depths to remove poor soils will vary around and between the borings and will not be known until excavation is started. We recommend that the earthwork contract contain a unit price line item for removal of poor soils beyond what volume is calculated. AET Job#01-02817 Page 7 of 16 Surface Estimated Depth', Estimated Elevation of .Boring:Nurnber . .Elevations •. of Ezcavaiion . : ... Botiom atExesivatio l 9 896.0* 5' —891 10 —906.1* 5' —901.1 11 —897.6* 2' —895.6 12 894.2* 5' —889.2 17 905.8 9' 896.8 18 904.8 4' 900.8 19 905.2 2' 903.8 20 898.1 1.5' 896.6 *Elevations for borings 9 through 12 are at the time of drilling, and these locations may have been subsequently graded. The elevations of the bottom of the excavation indicated in the table above are based on soil conditions at the boring locations. Since conditions may vary, it is recommended that a geotechnical engineer/technician observe the final excavation prior to new fill or footing placement. Depending on the required depth of subcutting to remove soft soils and precipitation patterns prior to and during construction, hydrostatic and/or perched groundwater may be encountered in excavations for soil correction. The wetland on the south side of the site is at about elevation 890, and in our opinion, the hydrostatic groundwater level is at or above that elevation. Excavation or filling below standing water should not be allowed; the contractor should be required to remove infiltrating surface water or groundwater. Additional Testing in the Low Area Near the Wetland AET did not select the test boring locations. Soil borings were not put down in the lower elevation area between borings 11/12 and the wetland(south portion of east wing). Because this area is downhill from borings suggesting variable layered soils, we feel it is important to gain additional strength and compressibility information on the supporting soils in this low area. These supporting soils will need to support significant fill load (needed to raise grade) in addition to the building loads. AET Job#01-02817 Page 8 of 16 Analysis associated with the additional testing should include evaluating settlement under the added fill and building loads and global slope stability (with final grade outside of the building sloping downward to the wetland). The additional testing could be done prior to construction or during construction. Preferably,the testing should be done with,additional standard penetration test borings (with thinwall tube sampling) or with cone penetration test (CPT) soundings. If these preferred methods are not chosen, the evaluation could be done with backhoe-dug test pits during construction(just outside of the building area), although recognize that evaluation could take time and result in construction delays. Filling The on-site clay soils could be reused as structural fill, if they are properly moisture conditioned. Moisture conditioning will require discing, drying or wetting, and blending of soils and will require favorable weather. Soils should be moisture conditioned to within 2% of the optimum, as determined by the Standard Proctor dry density(ASTM:D 698). New fill placed below foundation grades should be compacted in thin lifts to a minimum of 98% of the Standard Proctor dry density. For fill placed beneath the floor slab (above foundation grades), the compaction level can be reduced to 95%. The fill lift thickness should be thin enough such that the entire thickness of fill placed can meet the minimum specified compaction level. Some of the excavation bottoms may be sensitive to disturbance, especially if they are wet. In order to prevent disturbance of these soils during filling activities, it may be necessary to use granular soils as the initial lift of fill. The placement of more than about 10' of cohesive (clay) fill can result in greater-than-normal settlement due to long-term consolidation (hydrocompression). If excavations to remove poor soils extend to below about elevation 887, we recommend using imported granular fill below this elevation. Sands with less than 12% by weight passing the No. 200 sieve would be suitable for this use. Where fill is placed on sloping ground(4:1 or steeper), we recommend the excavation bottom be benched or terraced into the slope(parallel to the ground contour)prior to fill placement. AET Job# 01-02817 Page 9 of 16 Foundations After site preparation, the structure can be supported on conventional spread foundations placed on the new compacted fill and competent native soils. We recommend perimeter foundations for heated building space be placed such that the bottom is a minimum of 42" below exterior grade. We recommend foundations for unheated building space (such as canopy foundations, wing walls, signs, etc.) be extended to a minimum of 60" below exterior grade. Additionally, the footings under the garage doors should be stepped down to 60". Based on the conditions encountered,it is our opinion the building foundations can be designed based on a maximum allowable soil bearing pressure of 3,000 psf. It is our judgment this design pressure will have a factor of safety of at least 3 against localized shear or base failure. We judge that total settlements under this loading should not exceed 1". We also judge that differential settlements of conditions depicted by the borings should not exceed %z". Floor Slab Preparation of the building area as previously recommended in the Building Grading Procedures section will also prepare the building area for floor slab support. All fill supporting the floor slab should be compacted to a minimum of 95%of Standard Proctor density. This includes utility and foundation trench backfill. We estimate the clayey soils should provide a modulus of subgrade reaction (K-value) of 150 pounds per cubic inch. Our recommendations for placement of a sand layer or plastic membrane are included in the standard sheet entitled"Floor Slab Moisture/Vapor Protection." Sidewalk/Exterior Building Backfilling Our recommendations for backfilling the structure appears on two standard data sheets which we have included with this report. These sheets are entitled: • "Freezing Weather Effects on Building Construction" • `Basement/Retaining Wall Backfill and Water Control" AET Job#01-02817 Page 10 of 16 Fill soils placed beneath exterior sidewalks should be compacted to a minimum of 95% of the Standard Proctor dry density. Fill selection should consider frost properties. Subsurface drainage should also be considered in situations where water can become trapped(held up within the frost zones upon clayey soils). Pavement Subgrade Preparation We recommend the surface vegetation and topsoil be removed from below all bituminous pavement areas. Excessively soft/wet clays or soils containing significant amounts of organics (over 5%) within the upper 3' of the pavement subgrade (within 3' of the bottom of Class 5) • should also be removed. After stripping the soils, the exposed soil should be evaluated for stability by test rolling as described in the attached sheet entitled "Bituminous Pavement Subgrade Preparation and Design." If soft or unstable soils are found,they should be subcut and replaced with drier fill or aerated, dried and recompacted back into place if weather conditions permit. It should not be necessary to correct soft soils to more than 3' beneath the proposed subgrade elevation, unless the soils are so unstable that they limit the ability to compact fill placed above these soils. We caution that a significant amount of soil stabilization may be required, and will require favorable weather conditions. The on-site non-organic clayey soils can be used as fill for the pavement subgrade. If they are used, it is critical that they are placed and compacted at the proper moisture conditions; we recommend that they be placed at within 2%of their optimum moisture content as determined by the Standard Proctor dry density. We recommend all fill placed within the top 3' of the pavement subgrade be compacted to a minimum of 100%of Standard Proctor maximum dry density. If fill is required below the top 3', it should be compacted to at least 95%. Please refer to the attached standard data sheet entitled "Bituminous Pavement Subgrade Preparation and Design" for general information on pavement stability and design. Sand Subbase Layer The clayey soils on this site are frost-susceptible; they will heave upon freezing each year and undergo a reduction of shear strength during freeze/thaw cycles. Additionally, their slow- draining nature will increase the potential for excess moisture in the aggregate base. Therefore, we recommend placing a 1' thick non-frost-susceptible (NFS) sand subbase below the Class 5 AET Job#01-02817 Page 11 of 16 base course to improve drainage and reduce frost effects. The sand should meet the gradation requirements of Mn/DOT Specification 3149.2B2 for Select Granular Borrow. Preferably, Modified Select Granular Borrow should be used. This material would have less than 5% passing the No. 200 sieve and less than 40% passing the No. 40 sieve. The entire thickness of the sand subbase layer should be compacted to a minimum of 100% of the Standard Proctor maximum dry density. The sand subbase layer, if it is placed, should be provided with a means of subsurface drainage to collect and dispose of water which may become trapped within the sands and above the slower draining clayey soils. This drainage can be provided by installing finger drains into catch basins at elevations no higher than the bottom of the sand layer. Edge drains can also be provided around the perimeter of the parking and driveway areas. The finger drains and edge drains should be wrapped with geotextile fabric and backfilled with sand. To promote subsurface movement of the trapped water, the top of the clayey soil layer should be sloped or shaped to direct water to the drainage collection points. Cost will be a factor in your decision whether or not to use a sand subbase. Although the use of a sand subbase has a higher initial cost, longer term costs can be reduced by the improved performance, lower maintenance, the use of thinner pavement sections, and improved constructability. We also have included an alternate pavement design if you choose not to use a sand subbase. Pavement Thickness It is our opinion the pavements should be designed using an assumed R-value of 30, if the sand subbase is placed. If the sand subbase is not used, we assume an R-value of 10. The following tabulation presents the recommended bituminous pavement thickness based on these R-values. AET Job#01-02817 Page 12 of 16 Pavement Course Sand Subbase With No Sand Subbase Alternative Heavy Heavy Automobile Duty Automobile Duty Traffic Only Areas Traffic Only Areas Bituminous Wear 1.5" 2" 1.5" 2" Bituminous Base 1.5" 2" 1.5 2" Class 5 Aggregate Base(Mn/DOT 3138) 5" 7" 7" 10" Select Granular Borrow (Mn/DOT 3149.2B2 12" 12" No No CONSTRUCTION CONSIDERATIONS Potential Difficulties Runoff Water in Excavation The on-site soils are relatively poor draining and occasional sand seams are present. You should anticipate encountering perched and possibly hydrostatic groundwater in excavations on this site. To allow observation of the excavation bottom, to reduce the potential for soil disturbance, and to facilitate filling operations, we recommend water be removed from within the excavations during construction. Disturbance of Soils The on-site soils can become disturbed under construction traffic, especially if the soils are wet. If soils become disturbed, they should be subcut to the underlying undisturbed soils. The subcut soils can then be dried and recompacted back into place, or they should be removed and replaced with drier imported fill. Cobbles and Boulders Glacial till soils,which are present at this site,can include cobbles and boulders. This may make excavating procedures somewhat more difficult than normal if they are encountered. Also, if cobbles or boulders are encountered at footing grade, it may be necessary to remove these oversized particles and replace them with compacted fill to allow footing placement. AET Job#01-02817 Page 13 of 16 Excavation Sidesloping/Retention If unretained, the excavation should maintain sideslopes in accordance with OSHA Regulations (Standards - 29 CFR) Part 1926, Subpart P, "Excavations." Even with the required OSHA sloping, ground water seepage can induce sideslope raveling or running which would require maintenance. Observation and Testing The recommendations in this report are based on the subsurface conditions found at our test boring locations. Since the soil conditions can be expected to vary away from the soil boring locations, we recommend on-site observation by a geotechnical engineer or technician during construction to evaluate these potential changes.Soil density testing should also be performed on new fill placed in order to document that project specifications for compaction have been satisfied. SUBSURFACE EXPLORATION General The current subsurface exploration program consisted of four (4) standard penetration test borings. The fieldwork was performed on March 3, 2006. Additionally, we have included four boring logs from our earlier exploration in November 2000. The approximate soil boring locations are shown on attached Figure 1. The recent borings were located by measuring from the existing church. Our drill crew shot the surface elevations at the borings referenced to the floor slab in the north entrance to the church. According to the site plan, this benchmark is at elevation 909.48'. Drilling Methods The standard penetration test borings were drilled using hollow-stem augers. The boreholes were grouted in compliance with the Minnesota Department of Health rules. Sampling Methods Split-Spoon Samples (SS) Standard penetration (split-spoon) samples were collected in accordance with ASTM:D1586. This method consists of driving a 2" O.D. split-barrel sampler into the in situ soil with a 140- pound hammer dropped from a height of 30". The sampler is driven a total of 18" into the soil. AET Job#01-02817 Page 14 of 16 After an initial set of 6", the number of hammer blows to drive the sampler the final 12" is known as the standard penetration resistance or N value. Sampling Limitations Unless actually observed in a sample, contacts between soil layers are estimated based on the spacing of samples.,and the action of drilling tools. Cobbles, boulders, and other large objects generally cannot be recovered from test borings. They may still be present in the ground even if they are not noted on the boring logs. Classification Methods Soil classifications shown on the boring logs are based on the Unified Soil classification (USC) system. The USC system is described in ASTM:D2487 and D2488. Where laboratory classification tests(sieve analysis and Atterberg Limits)have been performed, classifications per ASTM:D2487 are possible. Otherwise, soil classifications shown on the boring logs are visual- manual judgments. We have attached charts (Appendix A) illustrating the USC system, the descriptive terminology, and the symbols used on the boring logs. The boring logs include judgments of the geological depositional origin. This judgment is primarily based on observation of the soil samples, which can be limited. Observations of the surrounding topography,vegetation, and development can sometimes aid this judgment. Water Level Measurements The ground water measurements are shown at the bottom of the boring logs. The following information appears under"Water Level Measurements"on the logs: • Date and Time of measurement • Sampled Depth: lowest depth of soil sampling at the time of measurement • Casing Depth: depth to bottom of casing or hollow-stem auger at time of measurement • Cave-in Depth: depth at which measuring tape stops in the borehole • Water Level: depth in the borehole where free water is encountered • Drilling Fluid Level: same as Water Level,except that the liquid in the borehole is drilling fluid The true location of the water table at the boring locations may be different than the water levels measured in the boreholes. This is possible because there are several factors that can affect the water level measurements in the borehole. Some of these factors include: permeability of each AET Job#01-02817 Page 15 of 16 soil layer in profile, presence of perched water, amount of time between water level readings, presence of drilling fluid, weather conditions, and use of borehole casing. Sample Storage We will retain representative samples of the soils recovered from the borings for a period of 30 days. The sampleswill then be discarded unless you notify us otherwise. • LABORATORY TESTING • The laboratory test program consisted of seven (7) water content tests. The results of the water content tests are included on the boring logs in Appendix A, opposite the samples upon which the tests were run. • LIMITATIONS The data derived through this sampling and observation program have been used to develop our opinions about the subsurface conditions at your site. However,because no exploration program can reveal totally what is in the subsurface, conditions between borings and between samples and at other times, may differ from conditions described in this report. The exploration we conducted identified subsurface conditions only at those points where we took samples or observed ground water conditions. Depending on the sampling methods and sampling frequency, every soil layer may not be observed, and some materials or layers which are present in the ground may not be noted on the boring logs. If conditions encountered during construction differ from those indicated by our borings, it may be necessary to alter our conclusions and recommendations, or to modify construction procedures, and the cost of construction may be affected. The extent and detail of information about the subsurface condition is directly related to the scope of the exploration. It should be understood, therefore, that information can be obtained by means of additional exploration. AET Job#01-02817 Page 16 of 16 STANDARD OF CARE Our services for your project have been conducted to those standards considered normal for services of this type at this time and location. Other than this, no warranty, either express or implied,is intended. SIGNATURES Report Prepared by: Report Reviewed by: • • American Engineering Testing,Inc. American Engineering Testing,Inc. / , .,,,, Jay .Brekke,P.E. Jeffery K. Voyen,PE Project Engineer Vice President, Geotechnical Division MN Reg.No.25631 JPB/jmg EXCAVATION AND REFILLING FOR STRUCTURAL SUPPORT EXCAVATION Excavations for structural support at soil boring locations should be taken to depths recommended in the geotechnical report. Since conditions can vary, recommended excavation depths between and beyond the boring locations should be evaluated by geotechnical field personnel.If ground water is present,the excavation should be dewatered to avoid the risk of unobservable poor soils being left in-place.Excavation base soils may become disturbed due to construction traffic, ground water or other reasons. Such soils should be subcut to underlying undisturbed soils. Where the excavation base slopes steeper than 4:1, the excavation bottom should be benched across the slope parallel to the excavation contour. Soil stresses under footings spread out with depth.Therefore,the excavation bottom and subsequent fill system should be laterally oversized beyond footing edges to support the footing stresses.A lateral oversize equal to the depth of fill below the footing(i.e., 1:1 oversize)is usually recommended.The lateral oversize is usually increased to 1.5:1 where compressible organic soils are exposed on the excavation sides. Variations in oversize requirements may be recommended in the geotechnical report or can be evaluated by the geotechnical field personnel. Unless the excavation is retained, the backslopes should be tnaintained in accordance with OSHA Regulations (Standards-29 CFR),Part 1926,Subpart P, "Excavations"(found on www.osha.eov).Even with the required OSHA sloping, ground water can induce sideslope raveling or running which could require that flatter slopes or other approaches be used. FILLING Filling should proceed only after the excavation bottom has been approved by the geotechnical engineer/technician. Approved fill material should be uniformly compacted in thin lifts to the compaction levels specified in the geotechnical report. The lift thickness should be thin enough to achieve specified compaction through the full lift thickness with the compaction equipment utilized.Typical thicknesses are 6"to 9"for clays and 12"to 18"for sands. Fine grained soils are moisture sensitive and are often wet(water content exceeds the "optimum moisture content" defined by a Proctor test). In this case, the soils should be scarified and dried to achieve a water content suitable for compaction.This drying process can be time consuming, labor intensive, and requires favorable weather. Select fill material may be needed where the excavation bottom is sensitive to disturbance or where standing water is present. Sands (SP) which are medium to coarse grained are preferred, and can be compacted in thicker lift thicknesses than finer grained soils. Filling operations for structural support should be closely monitored for fill type and compaction by a geotechnical technician.Monitoring should be on a full-time basis in cases where vertical fill placement is rapid;during freezing weather conditions;where ground water is present; or where sensitive bottom conditions are present. EXCAVATION/REFILLING DURING FREEZING TEMPERATURES Soils that freeze will heave and lose density. Upon thawing, these soils will not regain their original strength and density.The extent of heave and density loss depends on the soil type and moisture condition;and is most pronounced in clays and silts.Foundations,slabs,and other improvements should be protected from frost intrusion during freezing weather. For earthwork during freezing weather, the areas to be filled should be stripped of frozen soil, snow and ice prior to new fill placement. In addition, new fill should not be allowed to freeze during or after placement. For this reason, it may be preferable to do earthwork operations in small plan areas so grade can be quickly attained instead of large areas where much frost stripping may be needed. 01REP011(2/01) AMERICAN ENGINEERING TESTING,INC. BASEMENT/RETAINING WALL BACKFILL AND WATER CONTROL DRAINAGE Below grade basements should include a perimeter backfill drainage system on the exterior side of the wall. The exception may be where basements lie within free draining sands where water will not perch in the backfill. Drainage systems should consist of perforated or slotted PVC drainage pipes located at the bottom of the backfill trench, lower than the interior floor grade.The drain pipe should be surrounded by properly graded filter rock. A filter fabric should then envelope the filter rock.The drain pipe should be connected to a suitable means of disposal,such as a sump basket or a gravity outfall. A storm sewer gravity outfall would be preferred over exterior daylighting, as the latter may freeze during winter.,For non-building, exterior retaining walls, weep holes at the base of the wall can be substituted for a drain pipe. BACKFILLING Prior to backfilling,damp/water proofing should be applied on perimeter basement walls.The backfill materials placed against basement walls will exert lateral loadings.To reduce this loading by allowing for drainage,we recommend using free draining sands for backfill. The zone of sand backfill should extend outward from the wall at least 2', and then upward and outward from the wall at a 30°or greater angle from vertical. As a minimum,the sands should contain no greater than 12% by weight passing the#200 sieve, which would include (SP)and(SP-SM) soils. The sand backfill should be placed in lifts and compacted with portable compaction equipment.This compaction should be to the specified levels if slabs or pavements are placed above. Where slab/pavements are not above,we recommend capping the sand backfill with a layer of clayey soil to minimize surface water infiltration. Positive surface drainage away from the building should also be maintained. If surface capping or positive surface drainage cannot be maintained,then the trench should be filled with more permeable soils, such as the Fine Filter or Coarse Filter Aggregates defined in MnDOT Specification 3149. You should recognize that if the backfill soils are not properly compacted, settlements may occur which may affect surface drainage away from the building. Backfilling with silty or clayey soil is possible but not preferred.These soils can build-up water which increases lateral pressures and results in wet wall conditions and possible water infiltration into the basement. If you elect to place silty or clayey soils as backfill, we recommend you place a prefabricated drainage composite against the wall which is hydraulically connected to a drainage pipe at the base of the backfill trench. High plasticity clays should be avoided as backfill due to their swelling potential. LATERAL PRESSURES Lateral earth pressures on below grade walls vary, depending on backfill soil classification, backfill compaction and slope of the backfill surface. Static or dynamic surcharge loads near the wall will also increase lateral wall pressure. For design,we recommend the following ultimate lateral earth pressure values(given in equivalent fluid pressure values) for a drained soil compacted to 95% of the Standard Proctor density and a level ground surface. Equivalent Fluid Density Soil Type Active (pcf) At-Rest (pcf) Sands (SP or SP-SM) 35 50 Silty Sands (SM) 45 65 Fine Grained Soils(SC, CL or ML) 70 90 Basement walls are normally restrained at the top which restricts movement. In this case, the design lateral pressures should be the "at-rest" pressure situation. Retaining walls which are free to rotate or deflect should be designed using the active case. Lateral earth pressures will be significantly higher than that shown if the backfill soils are not drained and become saturated. 01REP014(7/01) AMERICAN ENGINEERING TESTING, INC. FLOOR SLAB MOISTURE/VAPOR PROTECTION Floor slab design relative to moisture/vapor protection should consider the type and location of two elements,a granular layer and a vapor membrane(vapor retarder,water resistant barrier or vapor barrier).In the following sections,the pros and cons of the possible options regarding these elements will be presented,such that you and your specifier can make an engineering decision based on the benefits and costs of the choices. GRANULAR LAYER In American Concrete Institute(ACI)302.1-96,a"base material"is recommended,rather than the conventional cleaner "sand cushion" material. The manual maintains that clean sand(common "cushion" sand)is difficult to compact and maintain until concrete placement is complete.ACI recommends a clean,fine graded material(with at least 10%to 30% of particles passing a#100 sieve)which is not contaminated with clay,silt or organic material.We refer you to ACI 302.1- 96 for additional details regarding the requirements for the base material. In cases where potential static water levels or significant perched water sources appear near or above the floor slab,an underfloor drainage system may be needed wherein a draintile system is placed within a thicker clean sand or gravel layer. Such a system should be properly engineered depending on subgrade soil types and rate/head of water inflow. VAPOR MEMBRANE • The need for a vapor membrane depends on whether the floor slab will have a vapor sensitive covering,will have vapor sensitive items stored on the slab, or if the space above the slab will be a humidity controlled area.If the project does not have this vapor sensitivity or moisture control need,placement of a vapor membrane may not be necessary.Your decision will then relate to whether to use the ACI base material or a conventional sand cushion layer.However,if any of the above sensitivity issues apply,placement of a vapor membrane is recommended. Some floor covering systems(adhesives and flooring materials)require a vapor membrane to maintain a specified maximum slab moisture content as a condition of their warranty. VAPOR MEMBRANE/GRANULAR LAYER PLACEMENT A number of issues should be considered when deciding whether to place the vapor membrane above or below the granular layer.The benefits of placing the slab on a granular layer,with the vapor membrane placed below the granular layer,include reduction of the following: • Slab curling during the curing and drying process. • Time of bleeding,which allows for quicker finishing. • Vapor membrane puncturing. • Surface blistering or delamination caused by an extended bleeding period. • Cracking caused by plastic or drying shrinkage. The benefits of placing the vapor membrane over the granular layer include the following: • The moisture emission rate is achieved faster. • Eliminates a potential water reservoir within the granular layer above the membrane. • Provides a"slip surface",thereby reducing slab restraint and the associated random cracking. If a membrane is to be used in conjunction with a granular layer,the approach recommended depends on slab usage and the construction schedule.The vapor membrane should be placed above the granular layer when: • Vapor sensitive floor covering systems are used or vapor sensitive items will be directly placed on the slab. • The area will be humidity controlled, but the slab will be placed before the building is enclosed and sealed from rain. • Required by a floor covering manufacturer's system warranty. The vapor membrane should be placed below the granular layer when: • Used in humidity controlled areas(without vapor sensitive coverings/stored items),with the roof membrane in place, and the building enclosed to the point where precipitation will not intrude into the slab area.Consideration should be given to slight sloping of the membrane to edges where draintile or other disposal methods can alleviate potential water sources,such as pipe or roof leaks,foundation wall damp proofing failure,fire sprinkler system activation, etc. There may be cases where membrane placement may have a detrimental effect on the subgrade support system (e.g., expansive soils).In these cases,your decision will need to weigh the cost of subgrade options and the performance risks. 01REP013(2/01) AMERICAN ENGINEERING TESTING,INC. FREEZING WEATHER EFFECTS ON BUILDING CONSTRUCTION GENERAL Because water expands upon freezing and soils contain water,soils which are allowed to freeze will heave and lose density. Upon thawing,these soils will not regain their original strength and density. The extent of heave and density/strength loss depends on the soil type and moisture condition.Heave is greater in soils with higher percentages.of fines (silts/clays). High silt content soils are most susceptible,.due to their high capillary rise potential which can create ice lenses. Fine grained soils generally heave about 1/4" to 3/8" for each foot of frost penetration. This can translate to 1" to 2" of total frost heave. This total amount can be significantly greater if ice lensing occurs. DESIGN CONSIDERATIONS Clayey and silty soils can be used as perimeter backfill, although the effect of their poor drainage and frost properties should be considered.Basement areas will have special drainage and lateral load requirements which are not discussed here.Frost heave may be critical in doorway areas.Stoops or sidewalks adjacent to doorways could be designed as structural slabs supported on frost footings with void spaces below. With this design, movements may then occur between the structural slab and the adjacent on-grade slabs. Non-frost susceptible sands (with less than 12% passing a#200 sieve)can be used below such areas. Depending on the function of surrounding areas, the sand layer may need a thickness transition away from the area where movement is critical. With sand placement over slower draining soils, subsurface drainage would be needed for the sand layer. High density extruded insulation could be used within the sand to reduce frost penetration, thereby reducing the sand thickness needed.We caution that insulation placed near the surface can increase the potential for ice glazing of the surface. The possible effects of adfreezing should be considered if clayey or silty soils are used as backfill. Adfreezing occurs when backfill adheres to rough surfaced foundation walls and lifts the wall as it freezes and heaves.This occurrence is most common with masonry block walls,unheated or poorly heated building situations and clay backfill.The potential is also increased where backfill soils are poorly compacted and become saturated.The risk of adfreezing can be decreased by placing a low friction separating layer between the wall and backfill. Adfreezing can occur on exterior piers(such as deck, fence or other similar pier footings), even if a smooth surface is provided. This is more likely in poor drainage situations where soils become saturated. Additional footing embedment and/or widened footings below the frost zones(which includes tensile reinforcement)can be used to resist uplift forces. Specific designs would require individual analysis. CONSTRUCTION CONSIDERATIONS Foundations,slabs and other improvements which may be affected by frost movements should be insulated from frost penetration during freezing weather. If filling takes place during freezing weather, all frozen soils,snow and ice should be stripped from areas to be filled prior to new fill placement.The new fill should not be allowed to freeze during transit, placement or compaction. This should be considered in the project scheduling, budgeting and quantity estimating.It is usually beneficial to perform cold weather earthwork operations in small areas where grade can be attained quickly rather than working larger areas where a greater amount of frost stripping may be needed. If slab subgrade areas freeze,we recommend the subgrade be thawed prior to floor slab placement. The frost action may also require reworking and recompaction of the thawed subgrade. OIREP015(2/01) AMERICAN ENGINEERING TESTING,INC. BITUMINOUS PAVEMENT SUBGRADE PREPARATION AND DESIGN GENERAL Bituminous pavements are considered layered"flexible" systems. Dynamic wheel loads transmit high local stresses through the bituminous/base onto the subgrade. Because of this, the upper portion of the subgrade requires high strength/stability to reduce deflection and fatigue of the bituminous/base system.The wheel load intensity dissipates through the subgrade such that the high level of soil stability is usually not needed below about 2' to 4' (depending on the anticipated traffic and underlying soil conditions).This is the primary reason for specifying a higher level of compaction within the upper snbgrade zone versus the lower portion. Moderate compaction is usually desired below the upper critical zone,primarily to avoid settlements/sags of the roadway. However, if the soils present below the upper 3' subgrade zone are unstable, attempts to properly compact the upper 3' zone to the 100% level may be difficult or not possible. Therefore, control of moisture just below the 3' level may be needed to provide a non- yielding base upon which to compact the upper subgrade soils. Long-term pavement performance is dependent on the soil subgrade drainage and frost characteristics. Poor to moderate draining soils tend to be susceptible to frost heave and subsequent weakening upon thaw.This condition can result in irregular frost movements and"popouts,"as well as an accelerated softening of the subgrade.Frost problems become more pronounced when the subgrade is layered with soils of varying permeability.In this situation,the free- draining soils provide a pathway and reservoir for water infiltration which exaggerates the movements.The placement of a well drained sand subbase layer as the top of subgrade can minimi trapped water,smooth frost movements and significantly reduce subgrade softening.In wet,layered and/or poor drainage situations, the long-term performance gain should be significant.If a sand subbase is placed,we recommend it be a"Select Granular Borrow"which meets Mn/DOT Specification 3149.2B2. PREPARATION Subgrade preparation should include stripping surficial vegetation and organic soils. Where the exposed soils are within the upper "critical" subgrade zone(generally 21'deep for "auto only" areas and 3' deep for "heavy duty" areas),they should be evaluated for stability. Excavation equipment may make such areas obvious due to deflection and rutting patterns. Final evaluation of soils within the critical subgrade zone should be done by test rolling with heavy rubber-tired construction equipment,such as a loaded dump truck.Soils which rut or deflect 1"or more under the test roll should be corrected by either subcutting and replacement;or by scarification,drying,and recompaction. Reworked soils and new fill shouldbe compacted per the *Specified Density Method" outlined in Mn/DOT Specification 2105.3F1 (a minimum of 100% of Standard Proctor density in the upper 3' subgrade zone, and a minimum of 95%below this). Subgrade preparation scheduling can be an important consideration.Fall and Spring seasons usually have unfavorable weather for soil drying.Stabilizing non-sand subgrades during these seasons may be difficult,and attempts often result in compromising the pavement quality. Where construction scheduling requires subgrade preparation during these times, the use of a sand subbase becomes even more beneficial for constructability reasons. SUBGRADE DRAINAGE If a sand subbase layer is used, it should be provided with a means of subsurface drainage to prevent water build-up. This can be in the form of draintile lines which dispose into storm sewer systems,or outlets into ditches.Where sand subbase layers include sufficient sloping,and water can migrate to lower areas,draintile lines can be limited to finger drains at the catch basins.Even if a sand layer is not placed,strategically placed draintile lines can aid in improving pavement performance. This would be most important in areas where adjacent non-paved areas slope towards the pavement. Perimeter edge drains can aid hi intercepting water which may infiltrate below the pavement. 01REP016(02/01) AMERICAN ENGINEERING TESTING,INC. Appendix A • Figure 1 - Boring Locations Soil Boring Logs Boring Log Notes Unified Soil Classification System ‘o o 'E p• N ?r N r i _. .. C r 0 M er _ _ .. _ _ �..,yH� - � WW 1144 — gyp a A 1.- g E ... E IIKMr0 .41 nil S 0 Ili r i Ag I A. , orrilinligli ,! ,. ,:- . ..., aa cil ca W f ■■ U la t aaa41Iw ,1. 1R,,,,„,,,, 1 i ,, 14111111 .--- 1111 x/11'" 4 v , 2 is,r w . i 4 —."Iiiii.°"..1r 4.,„ . � 4h, �� ail '4t a. & FG a le .• Lirt44 - 42- ••_ -I' �`L. '� sl y CA ►! 1 _ 44a. �" o 14, i on 80---•� Hr _�iii i _� O ;SIr iZ EIPk 8i =0,4R • J un 1..1=.41...1 e _ w rt yW i91'I [ AIL Q "IW = � �+ z 6 e r likk' e .. F R .� s. in /r U U r i...I. -•: --.. „,,,N `t - i mum■iy q .®� rl� R 1rrntwraw■-er.i 1 i, " ——— T "11 s 3ee ■ 3e 4 :_54.1: I—— • s: a R� G!w" .. 1.� d�, 11..7� Cd R :i get 6I $ a el n a R.R § ss g ---s �` : U' S $- a - R g P R •-v T- r. R W R o r x CjW L 0 133 HS is w AAMERICAN ENGINEERING SUBSURFACE BORING LOG iimi TESTING, INC. AET JOB NO: 01-02817 LOG OF BORING NO. 17 (p. 1 of 1) PROJECT: Proposed Shepherd's Path Senior Housing; Prior Lake, MN DEPTH SURFACE ELEVATION: 905.8 GEOLOGY N MC SAMPLE REC FIELD&LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN• WC DEN LL PL '1,4200 FILL,mostly organic clay,a little gravel,trace roots,black i-.--.— I — FILL,mostly sandy lean clay,a little gravel, 11 M SS 24 - s trace roots,light brown,frozen to about 1.5' 2 3 — 9 M , SS 24 4 FILL,mixture of clayey sand and silty sand, FILL 11 trace roots,black and brown ' 5- 10 M , SS 15 6— ii7 8— 3166/Agaerr el ei 7.41 13 M � SS 24 NV CLAYEY SAND,a littlevel light brown and r WEATHEREE 10 light'grayish brown mottled,fu-m,laminations of /TILL 8 M SS 13 13 fine silty sand(SC) , 11 — 12— iii 13 CLAYEY SAND,a little gravel,light grayish 18 Mrli SS 24 14— brown,very stiff,laminations of sand(SC) ///:/,� tii 15— f/f TILL 17 M li SS 18 — f16 l7- �1 //I 111 1s 19— � 1 CLAYEY SAND,a little gravel,light brownish �f�' 20— gray,very stiff,laminations of sand(SC) 19 M ilr SS 20 21 'A END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO 0-19' 3.25"HSA DATE TIME SAMPLED DEPTH CAVE-INSING EFLUIDDIDLEVEL WATERVELTHE ATTACHED 3/3/06 9:45 21.0 19.0 None SHEETS FOR AN 3/3/06 9:50 21.0 - 15.0 None EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 3/3/06 DR: MN LG: TM Rig: 67C THIS LOG . 06/04 AAMERICAN ENGINEERING SUBSURFACE BORING LOG m•••• TESTING,INC. AET JOB NO: 01-02817 LOG OF BORING NO. 18 (p. 1 of 1) PROJECT: Proposed Shepherd's Path Senior Housing; Prior Lake, MN DEPTH SURFACE ELEVATION: 904.8 GEOLOGY N MC SAMPLE REC FIELD&LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE ' WC DEN LL PL •/r#20( -,4"Bituminous pavement .---- FILL,8"crushed Iimestone base,light brown 1 M SU FILL,mixture of clayey sand and silty sand, light brown 2 FILL 3 — FILL,mostly clayey sand,a little gravel,light 15 M SS 12 grayish brown 4 ri 5 SANDY LEAN CLAY,a little gravel,light / brownish gray,stiff,laminations of sandy silt 13 M SS 24 14 6— (CL) 7— WEATHEREE i TILL /1 A1�G �tIrr 6 8 CLAYEY SAND,a little gravel,light grayish �l 19 M ' SS '724 13 brown,very stiff,laminations of sandy silt(SC) 9 0 1 10- CLAYEY SAND,a little gravel,light grayish brown,stiff,laminations of silty sand(SC/SM) •. 15 M SS 20 11 — • 12 - 0 i 13— I3 M A SS 24 14 / A CLAYEY SAND,a littleavelight l 8rl� Sh grayish �TILL i I5— brown,a little brown mottled,stiff to very stiff 18 M SS 24 16— 17— /0 1 1 18 c' . 1 19— j t CLAYEY SAND,a little gravel,light brownish 20— gray,very stiff,laminations of silty sand(SC) 18 M SS 24 21 A END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO SAMPLED CASING CAVE-IN TIME THE ATTACHED 0-19' 3.25"HSA DEPTH DEFLUID EEE 3/3/06 11:15 21.0 19.0 None None SHEETS FOR AN 313/06 11:20 21.0 - 13.0 None EXPLANATION OF - BBOMPLETED: 3/3/06 TERMINOLOGY ON CDR: MN LG: TM Rig: 67C THIS LOG 06/04 AAMERICAN ENGINEERING SUBSURFACE BORING LOG NM= TESTING,INC. AET JOB NO: 01-02817 LOG OF BORING NO. 19 (p. 1 of 1) PROJECT: Proposed Shepherd's Path Senior Housing; Prior Lake, MN DEPTH FIELD&LABORATORY TESTS SURFACE ELEVATION: 905.2 GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE INWC DEN LL PL •/.-#20( FILL,mostly clayey sand,a little gravel,trace / roots,light grayish brown,frozen 1 FILL,mostly clayey sand,a little gravel,trace FILL , 26 F/M SS 24 2 roots,dark brown and gray,frozen to about 1.5' pf ii: 3— 8 M SS 18 16 4 CLAYEY SAND,a little gravel,light brownish )LAREE T E gray to light grayish brown,firth to stiff, TILL 5— laminations of sandy silt(SC) 14 M A SS 24 14 6J 7 , gt _—CLAYEY SAND,a little gravel,light grayish / ' fl./4' t~,se i �. 8 brown,very stiff laminations of sand(SC) 17 S 23 13 9— I 10— /4 18 M A SS 24 11 — 12— i 13— frf'�TILL 19 M SS 21 it 15 14 CLAYEY SAND,a little gravel,light brownish / � t5— gray,very stiff,laminations of silty sand(SC) , / 16 M SS 24 16— 17— '//` 1 Is— � 11 19— 3 1 20— ! Y 17 M SS 24 21 END OF BORING I DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO 0-19' 3.25"HSA DATE TIME SAMPLED CASINGEIHCAVE-INDEPFLUID LEVEL LEVEL THE ATTACHED 3/3/06 10:20 21.0 19.0 None None SHEETS FOR AN 3/3/06 10:25 21.0 - 15.0 None EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 3/3/06 THIS LOG DR: MN LG: TM Rig: 67C 06/04 AAMERICAN ENGINEERING SUBSURFACE BORING LOG 111111111•11111 AET INC. AET JOB NO: 01-02817 LOG OF BORING NO. 20 (p. 1 of 1) PROJECT: Proposed Shepherd's Path Senior Housing; Prior Lake,MN DEPTH SURFACE ELEVATION: . 898.1 FIELD&LABORATORY TESTS GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE IN. WC DEN LL PL o-#20t FILL,mostly sandy lean clay,a little gravel, FILL 1 trace roots,brownish gray,a little brown,frozen IO F `,111 SS 20 to about 1.5' • 2 SANDY LEAN CLAY,a little gravel,trace roots,light brownish gray mottled,frozen to 12 MSS 18 IS 5' 3 about 1. ,stiff,laminations of silty sand and sandy silt(CL) WEATHE• 4 TILL �al 5 CLAYEY SAND,a little gravel,light brownish 2 12 M , SS 24 6 gray,a little brown mottled,stiff,laminations of sandy silt(SC/SM) 7 1' tii 8 CLAYEY SAND,a little gravel,light brownish 15 M 0 SS 24 gray,a little brown mottled,stiff(SC) 9 // !ii 10 CLAYEY SAND,a little gravel,brown and light 7, 21 M , SS 24 11 gray mottled,very stiff,laminations of silty sand (SC) V. TILL til 12 13 22 M ri SS 24 14 It 15 d' CLAYEY SAND,a little gravel,possible cobbles at 15',light brownish gray,very stiff , 19 M rSS 24 16 SC // 17 18 /19 I11111 20 22 M SS 24 21 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE-IN DRILLING WATER THE ATTACHED 0-19' 3.25"HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 3/3/06 9:00 21.0 19.0 None SHEETS FOR AN 3/3/06 9:10 21.0 - 12.8 None EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 3/3/06 DR: MN LG: TM Rig: 67C THIS LOG 06/04 AAMERICAN . ENGINEERING SUBSURFACE BORING LOG MUMTESTING, INC. AET JOB NO: 01-00590 LOG OF BORING NO. 9 (p. 1 of 1) PROJECT: Shepherds Path Church, McKenna Road NW&CSAH 42; Prior Lake, MN iT I SURFACE ELEVATION: 81.7 (896.0±) GEOLOGY N 1 MC SAMPLE REC. FIELD&LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN. WC DEN LL PL %200 _ Lean clay,includes roots,black,medium(CL) TOPSOIL 5 M SS 6 32 2 FINE 5 M SS 14 18 — Lean clay,dark Say and black,medium(CL) ALLUVIUM 4— 5 / FINE 8 M SS 12 • ) Lean # 6 mediclay um CLQ sand,dark gray to brownish gray, ALLUVIUMO • WEATHEREC 7 TILL 8- Sandy lean clay,a little gravel,grayish brown, 9 M SS 4 9— stiff(CL) /TILL to Clayey sand,a little gravel,brown mottled, 5 M SS 20 it __medium(SC) %ll END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS I NOTE: REFER TO DATE TIME S DEPTH PLED DEPTH D VEPI H UID I EVEU LEVEL THE ATTACHED 0-9Ii4 3.25"USA 11/10/00 3:05 11.0 9.5 11.0 None SHEETS FOR AN EXPLANATION OF COMPLETED: 11/10/00 TERMINOLOGY CC: DA CA:MH Rig:68 ON THIS LOG 2199 A AMERICAN ENGINEERING SUBSURFACE BORING LOG momTESTING, INC. • AET JOB NO: 01-00590 LOG OF BORING No. 10 (p. 1 of 1) PROJECT: Shepherds Path Church, McKenna Road NW& CSAH 42; Prior Lake, MN DEr SURFACE ELEVATION: 91.8 (906.1) GEOLOGY N MC SAMPLE REC. FIELD&LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN. WC DEN LL PL %200 _ Fill,mostly lean clay with sand,brown 4 M ' SS 18 2 FILL 3— Fill,mostly sandy lean clay,a little gravel and 11 M SS 5 16 organic material,brown,a little dark brown 4— S • V/ 11 M SS 20 • 6_ Clayey sand,a little gravel,brown,stiff(SC/CL) � 7 8— Clayey sand,a little gravel,brown mottled,stiff, TILL 15 M ' SS 14 lenses of silty sand(SC/SM) 0 9- 10 Clayey sand,a little gravel,brown,stiff(SC/CL) f 14 M ' SS 22 L I END OF BORING • DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TLME SAMPLED CASING DRILLING 3.25"HSA DEPTH EPTHEPPTHH FLUID LEVEL LVETHE ATTACHED 11/10/00 2:30 11.0 9.5 11.0 None SHEETS FOR AN EXPLANATION OF BOCOMPLETED: 11/10/00 TERMINOLOGY CC: DA CA:MH Rig:68 ON THIS LOG 2/99 AAMERICAN ENGINEERING SUBSURFACE BORING LOG EmmyTESTING, INC. AET JOB NO: 01-00590 LOG OF BORING NO. 11 (p. 1 of 1) PROTECT: Shepherds Path Church, McKenna Road NW& CSAH 42: Prior Lake, MN DEPTH SURFACE ELEVATION: 83.3 (89 7.61) GEOLOGY N MC SAMPLE TMYPE INC FIELD A LABORATORY TESTS FEET • MATERIAL DESCRIPTION '— WC DEN I.I. PL 9 [ clay with sand,brown,soft(CL)(may be ALLUVIUM Mills SS FINE '"-18- ', a OR FILL 2 3- Clayey sand,a little gravel,brown,stiff(SC) WEATHERED 12 M/D I SS 14 TILL . 4- 4 s- 9 MSS 16 . 1.8 6- Lean clay,light gray and brown mottled,stiff to % FINE ' 7_ medium(CL) ALLUVIUM g- 6 M 1 SS 16 24 1.0 9- 10 9 M 1 SS 14 II - 12- Sandy lean clay,a little gravel,brown mottled, stiff to medium(CUSC) . 13_ 0 6 M ' SS 14 14- 15 TILL 6 M 1 SS 10 16— eF 17- Clayey sand,a little gravel,brown mottled to gray,medium to stiff(SC) 18- 2021 f/J/ 10 M SS 20 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE-IN DRILL NG WATER THE ATTACHED 0.19% 3.25 HSA DEPTH DEPTH DEPTH FLUID LE LEVEL 11/10/00 1:55 21.0 19.5 21.0 None SHEETS FOR AN EXPLANATION OF COMPLETED: 11/10/00 TERMINOLOGY CC:DA CA:MH Rig:68 ON THIS LOG 2/99 ________ . _ .... . _ ____ A. AMERICAN �` ENGINEERINGIINC. SUBSURFACE BORING LOG �i,� • AEr JOB NO: 01-00590 LOG OF BORING NO. 12 (p. 1 of 1) PROJECT: Shepherds Path Church,McKenna Road NW& CSAH 42; Prior Lake, MN D IN SURFACE ELEVATION: 79.9 (8 94 2#) GEOLOGY N MC SAMPLE IF FIELD&LABORATORY TESTS FEET MATERIAL DESCRIPTION W!.at TYPE IN. WC DEN LL PL %200 1 — Lean clay,includes roots,black(CL) TOPSOIL 5 M ' SS 12 - 2 3— Lean clay,dark brown,dark gray and black FINE 7 MSS 16 24 mottled,medium(CL) ALLUVIUM , 4— S 9 MSS 14 6— , 7_i Lean clay,light gray,brown and gray mottled, /// MIXED stiff to medium,lenses of silt and clayey sanALLUVIUM 8_ with gravel(CL) 8 M ' SS 16 9- 10 MIXED 6 lir I SS 14 19 11 _ Sandy lean clay,a little gravel,brown and light gray mottled,medium(CL) '_ UVIUM 12 4 WEATHERED _Sandy silt,brown mottled,moist,loose(MLI ..(WILL 13 - FINE' 22 ii SS 14 TILL OR Weathered boulder,gray COARSE 14— ALLUVIUM 15 Sand,a littlevel medium grained,brown, :':•:COARSE 10 ' SS 20 16— waterbearing,loose,lenses of clayey sand,loose . ALLUVIUM SP 17 18— Clayey sand,a little gravel,gray,medium(SC) TILL 19— 20— � 8 SS 12 21 F'�' M ' END OF BORING 'ALLUVIUM DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASINO CAVE-IN DRILLING WATER THE ATTACHED 0-19%1 3.25"HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 11/10/00 12:45 16.0 14.5 14.0 10.4 SHEETS FOR AN 11/10/00 12:50 21.0 19.5 19.5 17.1 EXPLANATION OF BORING COMPLETED: 11!10/00 11/10/00 2:45 21.0 None 13.0 10.4 TERMINOLOGY CC: DA CA: MH Rig:68 ON THIS LOG 2/99 BORING LOG NOTES DRILLING AND SAMPLING SYMBOLS TEST SYMBOLS Symbol Definition Symbol Definition CONS: One-dimensional consolidation test B,H,N: Size of flush joint casing DEN: Dry density, pcf CA: Crew Assistant(initials) DST: Direct shear test CAS: Pipe casing, number indicates nominal diameter in , E: Pressuremeter Modulus, tsf inches HYD: Hydrometer analysis CC: Crew Chief(initials) LL: Liquid Limit, % COT: Clean-out tube LP: Pressuremeter Limit Pressure, tsf DC: Drive casing; number indicates diameter in inches OC: Organic Content, % DM: Drilling mud or bentonite slurry PERM: Coefficient of permeability (K)test; F- Field; DR: Driller(initials) L- :.aboratory DS: Disturbed sample from auger flights PL: Plastic Limit, % FA: Flight auger; number indicates outside diameter in qp: Pocket Penetrometer strength, tsf(approximate) inches qc: Static cone bearing pressure, tsf HA: Hand auger; number indicates outside diameter q": Unconfined compressive strength, psf HSA: Hollow stem auger;number indicates inside diameter R: Ele trical Resistivity, ohm-cms in inches RQD: Rock Quality Designation of Rock Core, in percent LG: Field logger(initials) (aggregate length of core pieces 4"or more in length MC: Column used to describe moisture condition of as a percent of total core run) samples and for the ground water level symbols SA: Sieve analysis N(BPF): Standard penetration resistance (N-value) in blows per TRX: Triaxial compression test foot(see notes) VSR: Vane shear strength, remoulded(field),psf NQ: NQ wireline core barrel VSU: Vane shear strength, undisturbed(field),psf PQ: PQ wireline core barrel WC: Water content, as percent of dry weight RD: Rotary drilling with fluid and roller or drag bit %-200: Percent of material finer than#200 sieve REC: In split-spoon (see notes) and thin-walled tube sampling,the recovered length(in inches)of sample. STANDARD PENETRATION TEST NOTES In rock coring, the length of core recovered (Calibrated Hammer Weight) (expressed as percent of the total core run). Zero The standard penetration test consists of driving a split-spoon indicates no sample recovered, sampler with a drop hammer(calibrated weight varies to provide REV: Revert drilling fluid N,,0 values)and counting the number of blows applied in each of SS: Standard split-spoon sampler (steel; 13/8" is inside three 6" increments of penetration.If the sampler is driven less diameter; 2" outside diameter); unless indicated than 18" (usuaiy in highly resistant material), permitted in otherwise ASTM:D 1586, the blows for each complete 6" increment and SU Spin-up sample from hollow stem auger for each partia. increment is on the boring log. For partial TW: Thin-walled tube;number indicates inside diameter increments, the number of blows is shown to the nearest 0.1' in inches below the slash. WASH: Sample of material obtained by screening returning rotary drilling fluid or by which has collected inside The length of sample recovered, as shown on the "REC" the borehole after"falling" through drilling fluid column, may be greater than the distance indicated in the N WH: Sampler advanced by static weight of drill rod and column.The disparity is because the N-value is recorded below hammer the initial 6" set (unless partial penetration defined in WR: Sampler advanced by static weight of drill rod ASTM:D 1586 is encountered) whereas the length of sample 94mm: 94 millimeter wireline core barrel recovered is for the entire sampler drive (which may even . Water level directly measured in boring extend more than 18"). 0: Estimated water level based solely on sample appearance 01REP052C(01/05) AMERICAN ENGINEERING TESTING, INC. UNIFIED SOIL CLASSIFICATION SYSTEM AMERICAN ASTM Designations:D 2487,D2488 ENGINEERING El TESTING,INC. Soil Classification of Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests" Group Group Name" "Based on the material passing the 3-in Symbol 175-mm) sieve. Coarse-Grained Gravels More Clean Gravels Cu>4 and I<Cc<3E GW Well graded gravely If field sample contained cobbles or Soils More than 50%coarse Less than 5% boulders,or both, add"with cobbles or than 50% fraction retained finest Cu<4 and/or 1>Cc>3" GP Poorly graded gravel' boulders,or both"to group name. retained on on No.4 sieve cGravels with 5 to 12%fines require dual No.200 sieve Gravels with Fines classify as ML or MH GM Silty gravel''°" symbols: Fines more GW-GM well-graded gravel with silt than 12%fines c Fines classify as CL or CH GC Clayey gravel''' GW-GC well-graded gravel with clay .. Sands 50%or Clean Sands Cu>6 and 1<Cc<3E SW Well-gradedGP-GM poorly graded gravel with silt sand' GP-GCCI poorly graded gravel with clay- more of coarse Less than 5% °Sands with 5 to 12%fines require dual fraction passes fines° Cu<6 or 1>Cc>3E SP Poorly-graded sand' symbols: No.4 sieve SW-SM well-graded sand with silt Sands with Fines classify as ML or MH SM Silty sand"" SW-SC well-graded sand with clay Fines more SP-SM poorly graded sand with silt than 12%fines° Fines classify as CL or CH SC C ayey sand``"'' SP-SC poorly graded sand with clay Fine-Grained Silts and Clays inorganic P1>7 and plots on or above CL Lean clay'm Soils 50%or Liquid limit less. "A"liner . (D30)2 more passes than 50 Pl<4 orlots below ML SiIt&4M ECU=D60/D i4 Ce the No.200 "A"line Diux Du, sieve organic Liouid limit—oven dried x.75 OL Organic clay"' Plf soil contains>15%sand,add"with Liquid limit—not dried °to (see Plasticity Organic silt` sand"to group name. Chart below) °If fines classify as CL-ML,use dual Silts and Clays inorganic PI plots on or above"A"line CH Fat clay""' mbol GC-GM,or SC-SM. Liquid limit 50 If fines are organic,add"with organic or more PI plots below"A"line MH Elastic silt"c'' fines"to group name. 'If soil contains>15%gravel,add"with organic Liouid limit-oven dried<.75 OH Organic clay""'' gravel"to group name. Liquid limit—not dried o If Atterberg limits plot is hatched area, Organic slit soils is a CL-ML silty clay. Highly organic Primarily organic matter, dark PT Peaty 'If soil contains 15 to 29%plus No.200 soil in color,and organic in odor add"with sand"or"with gravel", whichever is predominant SIEVE ANALYSIS m lit-soil contains>30%plus No.200, 1-se•ars.+°a1 --°;,,,yore.-i (a da.so°u,dln.odndPk100 ,:' prcdominanUysand,add "sandy"to rn-awrd6°e6an d e awavn°d al , group name. u 1" 4 10 >o a i0 ZO Mif soil contains>30%plus No.200, "�INHN�111• ° . Swam et- — F' i ��E� ts( "am,.raR�imLL•as. re. .,. predominantly gravel,add "gravelly" p� I , ' I I i 10 }�( p- fMR-0.7r RS.� ./S. O� . " to group name. ( 1. '°.1.16x,, 1 i 'p E "_ v Rg Dale .7' � °Pl<4orpPl>4 and Potsbelow"lots on or Aotinee A"line. o 1 I��1�M�` i F PP1,plots on or above"A"line. .11111111111111.1111.111111 a 0PI plots below"A"line. (°e-izsa" • a- /rite* Fiber Content description shown below. ' II�nIE��l C?' OH OR MH iiMUNN■INCA . 0..6.6rim, p- A���v�l� ;-- i(,aliu/ir ML OR OL ° 'm I p.. s.u.' a,, °0 10 16 m 30 40 b ro 70 00 SO 100 110 a PARTICLE SIZE w s&L. ETaRs trQUD MAT(1.L) 4 q !p a•�•�5-ao o• •nmss'6i Plasticity Chart ADDITIONAL TERMINOLOGY NOTES USED BY AET FOR SOIL IDENTIFICATION AND DESCRIPTION Grain Size Gravel Percentages Consistency of Plastic Soils Relative Density of Non-Plastic Soils Teri Particle Size renin Percent Term N-Value.BPF Term N-Value.BPF Boulders Over 12" A Little Gravel 3%-14% Very Soft less than 2 Very Loose 0-4 Cobbles 3"to 12" With Gravel 15%-29% Soft 2-4 Loose 5-10 Gravel #4 sieve to 3" Gravelly 30%-50% Firm 5-8 Medium Dense 11-30 Sand #200 to#4 sieve Stiff 9-15 Dense 31-50 Fines(silt&clay) Pass#200 sieve Very Stiff 16-30 Very Dense Greater than 50 Hard Greater than 30 Moisture/Frost Condition Layering Notes Fiber Content of Peat Oreanic/Roots Description(if no lab tests) (MC Column) Laminations: Layers less than Fiber Content Soils are described as orponic,if soil is not peat D(Dry): Absense of moisture,dusty,dry to h" thick of Term (Visual Estimate) and is judged to have sufficient organic fines touch. differing material content to influence the soil properties. ,Sliphdt' M(Moist): Damp,although free water not or color. Fibric Peat: Greater than 67% organic used for borderline cases. visible. Soil may still have a high Hemic Peat: 33—67% water content(over"optimum"). Lenses: Pockets or layers Sapric Peat: Less than 33% With roots: Judged to have sufficient quantity W(Wed Free water visible intended to greater than%" of roots to influence the soil Waterbearing): describe non-plastic soils. thick of differing properties. Waterbearing usually relates to material or color. Trace roots: Small roots present,but not judged sands and sand with silt to be in sufficient quantity to F(Frozen): Soil frozen significantly affect soil properties. OICLS021(2/04) AMERICAN ENGINEERING TESTING,INC.