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HomeMy WebLinkAboutReport of Geotechnical Exploration & Review, City Hall/Public Works Expansion A AMERICAN ENGINEERING TESTING, INC. CONSULTANTS • ENVIRONMENTAL • GEOTECHNICAL • MATERI ALS REPORT OF GEOTECHNICAL MATERIALS • FORENSICS EXPLORATION AND REVIEW City Hall/Public Works Expansion 14168 Oak Park Blvd. Oak Park Heights, Minnesota AET Project No. 01 -04415 Date: January 9, 2009 Prepared for: City of Oak Park Heights 14168 Oak Park Blvd. N PO Box 2007 Oak Park Heights, MN 55082 St. Paul, MN Duluth, MN Mankato, MN Marshall, MN Rochester, MN Pierre, SD Rapid City, SD Sioux Falls, SD Wausau, WI AMERICAN CONSULTANTS A ENGINEERING • ENVIRONMENTAL • ICAL TESTING, INC. • MATERIALS NMI • FORENSICS January 9, 2009 City of Oak Park Heights 14168 Oak Park Blvd. N PO Box 2007 Oak Park Heights, MN 55082 Attn: Eric Johnson, City Administrator RE: Geotechnical Exploration and Review City Hall and Public Works Expansion 14168 Oak Park Blvd. N Oak Park Heights, Minnesota AET Project No. 01 -04415 Dear Mr. Johnson: American Engineering Testing, Inc. (AET) is pleased to present the results of our subsurface exploration program and geotechnical engineering review for your proposed City Hall and Public Works Building expansion in Oak Park Heights, Minnesota. These services were performed according to our proposal to you datedDecember 1, 2008. We are submitting three copies of the report to you. Three copies are also being sent on your behalf to Mr. Randy Engel of Buetow & Associates. Please contact me if you have any questions about the report. Sincerely, American Engineering Testing, Inc. Jeffery K. Voyen, PE Vice President, Geotechnical Division Phone: (651) 659 -1305 Cell:, (612) 961 -9186 jvoyen @amengtest.com cc: (3) Buetow and Associates, Attn: Randy Engel 550 Cleveland Avenue North 1St. Paul, MN 55114 Phone 651- 659 -9001 I Toll Free 800 -972 -6364 I Fax 651- 659 -1379 I www.amengtest.com I AA/EEO 4I1k This document shall not be reproduced, except in full, without written approval from American Engineering Testing, Inc. Report of Geotechnical Exploration and Review City Hall/Public Works Expansion 14168 Oak Park Blvd. N Oak Park Heights, Minnesota AET Project No. 01 -04415 January 9, 2009 Prepared for: Prepared by: City of Oak Park Heights American Engineering Testing, Inc. 14168 Oak Park Blvd. N 550 Cleveland Avenue North PO Box 2007 St. Paul, Minnesota 55114 Attn: Eric Johnson (651) 659- 9001 /www.amengtest.com Report Authored By: Peer Review Conducted By: Jeffery K. Voyen, PE J J h G. Bentler, PE 4 0-4/ 4 14 ,■fr, 611,./)--- Vice President, Geotechnical Division Geotechnical Engineer I hereby certify that this plan, specification, or report was prepared by me or under my direct supervision and that 1 am a duly Licensed Professional Engineer under the laws of the State of Minnesota Name: Jeffery K. Voyen Date: /- 9- 07 License #: 15928 Copyright 2009 American Engineering Testing, Inc. 1 All Rights Reserved 1 Unauthorized use or copying of this document is strictly prohibited by anyone other than the client for the specific project. t TABLE OF CONTENTS AET Project No. 01 -04415 1.0 INTRODUCTION 1 2.0 SCOPE OF SERVICES 1 3.0 PROJECT INFORMATION 2 4.0 SUBSURFACE EXPLORATION AND TESTING 4 4.1 Field Exploration Program 4 4.2 Laboratory Testing 4 5.0 SITE CONDITIONS 5 5.1 Subsurface Soils /Geology 5 5.2 Ground Water 5 6.0 RECOMMENDATIONS 6 6.1 Building Grading 6 6.2 Foundation Design 9 6.3 Floor Slab Design 10 6.4 Below Grade Wall Backfilling /Water Control 10 6.5 Exterior Backfilling- Non - Retaining Wall Case 12 6.6 Pavements 12 6.7 Post/Pier Foundation Design Considerations 16 7.0 CONSTRUCTION CONSIDERATIONS 18 7.1 Potential Difficulties 18 7.2 Excavation Backsloping 18 7.3 Observation and Testing 18 8.0 LIMITATIONS 19 STANDARD DATA SHEETS Floor Slab Moisture/Vapor Protection Freezing Weather Effects on Building Construction Definitions Relating to Pavement Construction APPENDIX A — Geotechnical Field Exploration and Testing Boring Log Notes Unified Soil Classification System Figure 1 — Boring Locations Figure 2 — Proposed Project Layout Subsurface Boring Logs APPENDIX B — Geotechnical Report Limitations and Guidelines for Use GEOTECHNICAL EXPLORATION AND REVIEW FOR CITY HALL AND PUBLIC WORKS EXPANSION 14168 OAK PARK BLVD. N OAK PARK HEIGHTS, MINNESOTA AET PROJECT NO. 01-04415 1.0 INTRODUCTION A new City Hall and an expanded Public Works building are proposed to be constructed at the current municipal site in Oak Park Heights, Minnesota. To assist planning and design, you have authorized American Engineering Testing, Inc. (AET) to conduct a subsurface exploration program at the site, conduct soil laboratory testing, and perform a geotechnical engineering review for the project. This report presents the results of the above services, and provides our engineering recommendations based on this data. 2.0 SCOPE OF SERVICES AET previously conducted four soil borings at the site, and prepared a preliminary geotechnical report for the project (AET #01- 03837, dated February 5, 2008). To provide additional data for a more complete geotechnical ro ram and report, additional services have been requested. These P g P � q expanded services were performed according to our proposal to you, dated December 1, 2008. This proposal was accepted by Mr. Eric Johnson on December 2. The authorized scope of this expanded work consists of the following: • Five standard penetration test borings in planned building areas to depths of 21 feet. • Seven standard penetration test borings in pavement, fence /exterior wall enclosure, and other exterior areas to depths of 11 feet. • Soil laboratory testing (water content on cohesive soils). • Geotechnical engineering analysis based on the gained data and preparation of this report. These services are intended for geotechnical purposes. The scope was not intended to explore for the presence or extent of environmental contamination. AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 3.0 PROJECT INFORMATION The overall municipal complex is proposed to be constructed in two phases. The first phase involves the construction of items outside of the current City Hall area and the pavements to the south, thereby allowing construction while the existing city offices remain open. The second phase will involve the demolition of the existing City Hall building and the construction of new parking lots and drive areas. The existing Public Works Garage will remain in place, supplemented by new additions built off the garage. In addition, the existing water tower and pump room will remain, located to the south of the Public Works Garage. The City Hall building will have a footprint of 13,640 square feet, and will include a full lower level for parking. The main floor elevation is proposed to be 956.0 and the lower garage basement floor elevation is proposed to be 942.0. We understand maximum column loads for the new building will be on the order of 315 kips. Exterior wall loads are expected to reach a maximum of 7 kips per lineal foot. The Public Works additions will be constructed to the north and west of the existing Public Works Garage to remain, as shown on Figure 2. We understand finished on -grade floor elevation will match existing garage elevation at 954.2. Foundation loads are expected to be somewhat less than that described for the City Hall building. Our building 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 inch, and differential settlements over a 30 foot distance of up to %2 inch. Page 2 of 19 AMERICAN ENGINEERING TESTING INC. AET Project No. 01- Project 01-04415 New pavements will be constructed as a part of the project, as shown on Figure 2. We understand bituminous pavements will be divided between light duty areas (cars and passenger trucks /vans only) and heavy duty areas (intended for heavier truck traffic). A small concrete pavement area is also planned near the Public Works garage addition, assumed to be a "heavy duty" pavement. The bituminous drive serving the lower garage level of the City Hall will enter the building on the west side. With the lower slab elevation, the drive will lower below surrounding grade, resulting in the need for retaining walls on both sides of the drive. At this time, we do not have details on the type of retaining wall to be constructed. This report presents recommendations for building spread foundations, which can also be applied to the retaining wall foundations. Our services do not include design of a segmental block retaining wall in the event that type of wall is to be used. A brick wall trash enclosure will be constructed on the north side of the north Public Works addition. The enclosure wall will be supported on a spread footing and masonry wall foundation, and the interior slab will be concrete. Fence enclosed Impound Lot and Public Works Storage Yard areas are also proposed on the west side. The Impound Lot will be bituminous surfaced and the Storage Yard will be gravel surfaced. Short block retaining walls may be constructed in some perimeter locations. Our scope does not include design of these walls. Other project features include fences, located around the Impound Iot and the Public Works Storage Yard. A flag pole and a series of bollards are also proposed in the center island areas. These elements will be supported on post type foundations, and this report presents foundation design concerns related to frost action. The above stated 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 Page 3of19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 there are changes from that described so that we can evaluate whether modifications to our recommendations are appropriate. 4.0 SUBSURFACE EXPLORATION AND TESTING 4.1 Field Exploration Program The total subsurface exploration program conducted for the project consisted of sixteen standard penetration test borings (including the four reviousl drilled borings). The to s of the borings p Y g g and details of the methods used appear in Appendix A. The logs contain information concerning soil layering, soil classification, geologic description, and moisture condition. Relative density or consistency is also noted for the natural soils, which is based on the standard penetration resistance (N- value). The boring locations were taped in the field by our field crew, and appear on Figure 1 in Appendix A. The locations were referenced to existing building lines, as noted on the figure. The surface elevations were measured by our field crew using an engineer's level and rod. The reference benchmark was the top nut of the hydrant located to the west of the water tower (west of the entrance drive), which appears on Figure 1. This benchmark is shown to be elevation 953.98 feet. 4.2 Laboratory Testing The laboratory test program included numerous water content tests, conducted on cohesive soils. The test results appear on the individual boring logs adjacent to the samples upon which they were P erformed. Page AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 1 5.0 SITE CONDITIONS 5.1 Subsurface Soils /Geology The predominant geology consists of glacially deposited till. The till is mostly silty sand, although is often more clayey (sandy lean clay and clayey sand) near the top of the deposit. Alluvial layers (water deposited soils) are occasionally present within or above the till. Alluvial deposits above the till are mostly lean clays and sandy silts; with the upper zone sometimes developed into topsoil. Where the alluvial layers are interbedded at greater depth, they are usually sands and sands with silt, often with gravel. With the past development, fill is present above the till, with soil types similar to the upper zones of the natural profile. At some locations, it was difficult to judge whether zones of the profile were fill or naturally J g �' P Y occurring till. These particular samples did not have the obvious appearance of fill, although it is evident from the surface topography that some fill does exist in the area. The geologic descriptions on the logs present our best judgment based on the limited samples retrieved. It should be easier to distinguish fill from the natural soils within the actual excavations during construction. 5.2 Ground Water No ground water entered the boreholes at the time of drilling. Although much of the profile is till, which includes slower draining soil which do not allow immediate appearance of water, some of the deeper borings included sand layers which were moist (not waterbearing). These non-waterbearing sands are present lower than elevation 930. Based on this, it appears that the g P PP steady -state ground water table is deeper than elevation 930. With the slow draining nature of the on -site soils, water can appear in a perched condition. Page 5 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 - 04415 Ground water levels fluctuate due to varying seasonal and annual rainfall and snow melt amounts, as well as other factors. 6.0 RECOMMENDATIONS 6.1 Building Grading 6.1.1 City Hall Excavation Most of the new City Hall building will extend well into the competent glacial till layer. The limiting soils pertaining to the foundation design is located in the northwest comer of the proposed building area, defined by Boring 11. This is the area where grade is currently lower than the remainder of the building footprint such that footings would be supported over soils within the upper portion of the profile. To take advantage of the high bearing capabilities of the till deposit throughout most of the building area, we will recommend subcutting of upper looser soils within the upper portion of the till to allow a net allowable soil bearing capacity of 4000 psf in the design. To prepare the City Hall building area and the adjacent retaining wall foundation area, we recommend excavating all surficial fill and topsoil materials which should expose the glacial till layer. Excavation to lower level grade will already penetrate through these materials into the competent till. Once the natural till is exposed, we recommend additional excavation of any looser or softer till zones near the surface, which would be applicable in the northwest corner of the building. This additional excavation would only apply to foundation areas, and not the general floor slab areas. We recommend removing soils which have an N -value of 9 blows per foot or less, resulting in an excavation depth of 4 feet at Boring 11. A review of required excavation depths for footing support at the test locations then appears on Table A. Page 6 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -0441 Table A — Recommended Minimum Excavation Depths Boring Location Surface Elevation (ft) Minimum Excavation Approximate Excavation Depth (ft) Elevation (ft) 2 952.8 *4 *948 3 955.2 *4 *951 11 941.2 4 937 12 948.0 *2 *946 13 948.1 *2 *945 14 949.5 *2 *947 15 950.0 *6 *943 *Excavation to lower level floor elevation (942.0) will penetrate to greater depths (i.e., competent soils will be present at proposed grades). The depth/elevation indicated in Table A is based on the soil condition at the specific boring location. Since conditions will vary away from the boring location, it is recommended that AET geotechnical personnel observe and confirm the competency of the soils in the entire excavation bottom prior to new fill or footing placement. Where the excavation extends below foundation g rade, the excavation bottom and resultant engineered fill system must be oversized laterally beyond the planned outside edges of the foundations to properly support the lateral loads exerted by that foundation. This excavation/engineered fill lateral extension should at least be equal to the vertical depth of fill needed to attain foundation grade at that location (i.e., 1:1 lateral oversize). 6.1.2 Public Works Building Excavation To prepare the Public Works Addition and trash enclosure areas, we recommend removal of surficial fill and topsoil, thereby exposing either the glacial till or the stiff alluvial clays. Considering the nature of these additions and the presence of lean clays which can be associated with lower strength, the excavation observations should consider soil strength needs for 3000 psf allowable bearing pressures. Page 7of19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 We were not able to clearly judge the geologic origin of the soils around 5 feet at Boring 4. Although these soils are likely natural tills, additional field judgment should be performed of the soils in this area to confirm natural till. If the soils are judged to be fill, they should be excavated per the direction of the geotechnical field personnel. Anticipated excavation depths at the boring locations in the vicinity of the Public Works building additions appear on Table B. Table B — Recommended Minimum Excavation Depths Boring Location Surface Elevation (ft) Minimum Excavation Approximate Excavation Depth (ft) Elevation (ft) 4 953.4 *4 -6'/2 *949'/2 -947 6 952.9 2 951 *Soils in this range should be evaluated in the field at the time of excavation. The depth/elevation indicated in Table B is based on the soil condition at the specific boring location. Since conditions will vary away from the boring location, it is recommended that AET geotechnical personnel observe and confirm the competency of the soils in the entire excavation bottom prior to new fill or footing placement. Where the excavation extends below foundation grade, the excavation bottom and resultant engineered fill system must be oversized laterally beyond the planned outside edges of the foundations to properly support the lateral loads exerted by that foundation. This excavation/engineered fill lateral extension should at least be equal to the vertical depth of fill needed to attain foundation grade at that location (i.e., 1:1 lateral oversize). 6.1.3 Building Area Fill Placement and Compaction Engineered fill placed to attain grade for foundation support should be compacted in thin lifts, such that the entire lift achieves a minimum compaction level of 98% of the standard maximum dry unit weight per ASTM:D698 (Standard Proctor test). Fill placed which supports the floor slab only (outside of the 1:1 oversize zone below footings) can have a reduced minimum Il i Page 8 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 compaction level of 95% of the standard maximum dry unit weight. Engineering fill placed below foundations should consist of sand or sand with silt, which refers to soils which contain less than 12% by weight passing the #200 sieve. The silty sands, clayey sands, and sandy lean clays can be used below the floor slab areas, provided they are moisture conditioned to within 2% of the standard optimum water content such that they can be compacted to the specified levels stated above. Also, any soils containing organic content or debris should be discarded (used below "green" areas only). If there are areas where fill is placed on slopes, we recommend benching the sloped surface (benches cut parallel to the slope contour) prior to placing the fill. Benching is recommended where slopes are steeper than 4H:1 V. 6.2 Foundation Design The new buildings and structural retaining walls can be supported on conventional spread foundations placed on the competent natural soils or on engineering fill overlying the competent natural soils. We recommend perimeter foundations for heated building space be placed such that the bottom is a minimum of 42 inches below exterior grade. We recommend foundations for unheated building space (such as exterior retaining walls and canopy foundations) be extended to a minimum of 60 inches below exterior grade. Based on the conditions encountered and the recommended engineered fill placement, it is our opinion the City Hall foundations can be designed based on a net maximum allowable soil bearing capacity of 4,000 psf. Further, it is our opinion the Public Works building addition foundations can be designed based on a net maximum allowable soil bearing capacity of 3,000 psf. Page 9 of 19 • AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 - 04415 It is our judgment the above presented design pressures will have a factor of safety of at least 3 against localized shear or base failure. We judge that total settlements under these loadings will be less than 1 inch. We also judge that differential settlements of conditions depicted by the borings and at the interface between the new construction and existing garage building should not exceed %2 inch 6.3 Floor Slab Design For concrete slab design, we estimate the on -site lean clays should provide a Modulus of Subgrade Reaction (k- value) of at least 100 pci. These soils appear in the Public Works area. In the City Hall area, the borings indicate the subgrade soils will be silty sands and clayey sands, and not lean clays. The silty and clayey sands would be associated with an estimated k -value of 200 pci. For recommendations pertaining to moisture and vapor protection of interior floor slabs, we refer you to the attached standard sheet entitled "Floor Slab Moisture/Vapor Protection." 6.4 Below Grade Wall Backfilling/Water Control 6.4.1 Drainage Below grade walls should include a perimeter backfill drainage system on the exterior side of the wall. Drainage systems should consist of perforated or slotted PVC drainage pipes Iocated 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. Page 10of19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -0441 6.4.2 Backfilling To prevent saturation of soils against the wall and to control the laterals loads which will be imposed, we recommend granular soils be used as backfill. The zone of granular soil backfill should extend outward from the wall at least 2 feet, and then upward and outward from the wall at a 30° or greater angle from vertical (this does not imply that this geometry satisfies OSHA backsloping requirements). As a minimum, the granular soils 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 sidewalks 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 structure 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 Mn/DOT 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. 6.4.3 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 purposes, assume that soils placed on a level surface would exert an equivalent fluid density pressure of about 35 pcf in the "active" case and about 50 pcf in the "at- rest" case. These values are based on the assumptions of SP or SP- SM sands used for backfill as recommended and sand compaction at 95% of the standard maximum dry unit weight per ASTM:D698 (Standard Proctor test). No factor of safety has been applied to the presented values. Page 11 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 - 04415 Below grade basement walls are normally restrained at the top which restricts movement. In this case, the design lateral pressures should be based on the "at- rest" pressure situation. Retaining walls which are free to rotate or deflect can be designed using the "active" case. Lateral earth pressures will be higher than that given if the backfill soils are not drained and become saturated, and/or if more silty /clayey soils are used. The design value used for passive pressure resistance depends on the allowable wall deflection. In order for full passive resistance to act, the wall needs to be mobilized. This can be studied further if requested, although for the purpose of design, we would suggest limiting the passive pressure resistance to an equivalent fluid weight of 250 pcf. 6.5 Exterior Backfilling- Non - Retaining Wall Case Most of the on -site soils are at least moderately frost susceptible. Because of this, certain design considerations are needed to mitigate these frost effects. For details, we refer you to the attached sheet entitled "Freezing Weather Effects on Building Construction." 6.6 Pavements 6.6.1 Definitions Italicized words used in this section have a specific definition. These definitions are presented on the attached standard sheet entitled "Definitions Relating to Pavement Construction," or in an ASTM Standard or Mn/DOT Specification. 6.6.2 Subgrade Preparation Long term pavement performance is dependent on having high soil stability in the critical subgrade zone to resist wheel loads and on having favorable frost and drainage characteristics. The borings indicate the soils present within the critical subgrade zone will consist of silty sands, clayey sands, sandy lean clays, and lean clays; all of which are poor draining and frost Page 12 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 susceptible. The preferred approach in these poor frostldrainage conditions is to perform a uniform subcut and place a uniform thickness sand subbase. The use of a 1 -foot thick sand subbase is usually a good approach when considering performance and economy. Use of a sand subbase layer as the upper portion of the subgrade is then our primary recommendation for this project. Sand subbase layers are often comprised of Select Granular Borrow. This specification does allow for the possibility of a fine grained sand material approaching a silty sand classification. This type of material does not allow for free drainage, and the stability can also be affected by the presence of water. Therefore, we often prefer the use of Modified Select Granular Borrow, if your budget allows. Value engineering judgments of intermediate gradations could also be considered, and we are available for review on this issue. Where there is a need to vary the thickness of the sand subbase, we recommend the thickness have a taper of no steeper than 10:1 (H:V). The subcut and sand subbase placement should extend slightly beyond the outer edge of the curb, or the paved edge (if no curb is placed), to maintain frost uniformity. The sand subbase should be provided with a means of subsurface drainage to prevent build up of water within the sand. This can be accomplished by placing short segments of properly engineered drainage lines which are connected to catch basins in low elevation areas (referred to as "finger drains "). Where paved areas are relatively level, and if finger drains are not frequent, you should consider placing a longer parallel drainage line through the level area to better remove infiltrating water. The need for shorter paths to draintile lines increases as the subbase material becomes less permeable (i.e, less draintile would be needed using Modified Select Granular Borrow versus Select Granular Borrow). The final subgrade should have proper stability within the critical subgrade zone. Stability of the Page 13of19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 on -site soils should be evaluated prior to sand subbase placement, preferably using the test roll procedure. Instability will likely be a result of wetter clayey /silty soils. More widespread instability can be anticipated during wetter seasons. Unstable soils should either be subcut and replaced, or reworked in- place. If soils are reworked in- place, they may need to undergo considerable scarification and drying to reach a proper level of stability (ability to pass a test roll). Reworked soils should be prepared similar to new fill materials, and should meet the water content and compaction requirements outlined later for new fill placement. We caution that instability of soils present beneath the soils being reworked and compacted may limit the ability to compact the upper soils. In this case, greater depths of subcutting and stability improvement may be needed. If organic soils are found to be present, we recommend removing these soils where present within the critical subgrade zone. Following subcutting and preparation of existing soils, fill can be placed as needed to attain subgrade elevation. Fill should be placed and compacted per the requirements of Mn/DOT Specification 2105.3F1 (Specified Density Method). This specification requires soils placed within the critical subgrade zone be compacted to a minimum of 100% of the standard maximum dry unit weight defined in ASTM: D698 (Standard Proctor test), at a water content between 65% to 102% of the standard optimum water content. A reduced minimum compaction level of 95% of the standard maximum dry unit weight can be used below the critical subgrade zone. The sand subbase can be considered part of a composite subgrade; and the top of the subbase can be figured as the top of the 3 foot subgrade zone needing the 100% compaction level. However, the lower (dry) end of the water content range requirement does not need to apply to the sands. With the interior of the Impound Lot being bituminous surfaced, the subgrade of the interior should be re are dasabit p p uminous P avement. Page 14 of 19 Ii AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 The Storage Yard will be gravel surfaced. This subgrade should also be prepared consistent with that recommended for pavements, except that you could consider eliminating the sand subbase layer if needed for budgetary reasons. The gravel surface does not as readily show frost movement distress and can be graded. Without the sand subbase, you should consider the placement of a geotextile fabric (Type V per Mn/DOT 3733) between the aggregate base and underlying subgrade to assist material separation. 6.6.4 Pavement Section Thicknesses We are presenting pavement designs based on two potential traffic situations (light and heavy duty). The light duty design refers to parking areas which are intended only for automobiles and passenger truck/ vans. The heavy duty design is intended for pavements which will experience the heavier truck traffic. Lean clays are present within the subgrade area, which represents the limiting subgrade condition in terms of design R- value. However, the use of a 1 -foot thick sand subbase will improve the subgrade R- value. We estimate an R -value of 30 will be provided for the composite subgrade consisting of 1 -foot of Select Granular Borrow over the on -site lean clays. The designs are based on this R- value, and if you elect to remove the sand subbase from the section, we should be contacted for review of revised sections. Our recommended pavement designs based on the R -value of 30 appear in Tables C and D. Table C — Bituminous Pavement Thickness Designs Material Section Thicknesses (R =30) Light Duty Heavy Duty Bituminous Wear 3" (2 lifts) 4" (2 lifts) Class 5 Aggregate Base 5" 6" Page 15of19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 Table D — Concrete Pavement Thickness Designs Material Section Thicknesses (R =30) Light Duty Heavy Duty Concrete 3.5" 5.5" Class 5 Aggregate Base 4" 4" The concrete conc ete design assumes that no dowels are needed for load transfer. Although the Class 5 aggregate base is not necessarily needed for strength reasons, it was added to the concrete design to assist in controlling "mud pumping" at the joints. The design assumes a minimum concrete compressive strength (f c ) of 4000 psi at 28 days. The presented designs have been based on "20- year" pavement life design charts. However, the concrete design is expected to have a longer pavement life; or at least, does not require the on- going maintenance of a bituminous system. The benefit of a bituminous system is that rehabilitation techniques, such as mill and overlay procedures, can be more easily performed. 6.7 Post/Pier Foundation Design Considerations The project is expected to include numerous post type foundations. This includes bollards, a flag pole, and fence posts. Vertical loads are very light, and frost forces can negatively impact these foundations if not properly designed. Frost uplift forces can be created on post or pier foundations by the surrounding frost susceptible soils. Frost heaving soils which surround the pier can adhere to the pier and lift the pier as it freezes and expands. Even if the pier in the frost zone has a smooth surface, a "pinching" effect can still occur because the soils surround the pier in all directions. Based on our experience with other similar projects, a potential uplift force of 13 psi can act on the shaft perimeter in the upper frost zone. For example, based on a frost depth of 4 feet and a pier diameter of 12 inches, this could then translate to over 23 kips of upward force. Page 16 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -0441 p To assist in mitigating the potential effect of these frost forces, the following items should be considered: • The frost forces will be created from the upper frost zone of the pier. For this situation (where snow cover will remain), we would consider the frost zone to be the upper 4 feet of the pier (in contact with soil). It will be very important to maintain the pier diameter such that it does not increase as it approaches the surface (i.e., telescope with a wider top). In fact, if possible during construction, it would be preferable to have the diameter of the pier below 4 feet be larger than the diameter in the upper portion. This lower pier oversizing would assist in resisting the upward force. • Although some "pinching" effects in the frost zone can occur, there would still be less frost forces if the upper pier had a smooth face rather than a rough face. To accomplish this, you should consider the placement of a smooth form in the upper portion of the pier. We recognize that side resistance will likely be needed to resist lateral and moment forces. We would suggest placing a tubular form within the upper 3 foot zone to create a slip surface. Depending on the form material used, an additional application of a "slippery" material /substance may be needed on the outside of the form to create a positive slip surface. A low- strength flowable concrete or grout should then be placed in the annular space created outside of the form to re- establish contact with the surrounding soil (for shear and moment resistance). This would also assist in creating a smaller diameter at the top as opposed to deeper portions of the pier. • Additional depth of pier embedment can also assist resisting frost forces. Page 17of19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 7.0 CONSTRUCTION CONSIDERATIONS 7.1 Potential Difficulties 7.1.1 Cobbles and Boulders The soils at this site appear to include some cobbles, and may potentially include boulders. This may make excavating procedures somewhat more difficult than normal if they are encountered. 7.1.2 Perched Water With the slow draining nature of most of the on -site soils, water can easily perch and appear in excavations, especially during times of inclement weather. Standing water should be removed as needed to facilitate construction and filling. 7.1.3 Wet Soils Some of the site soils available for re -use may be wet or could become wet of the "optimum water content" condition. Such soils may then need to be moisture conditioned in order to achieve specified compaction levels. 7.2 Excavation Backsloping If excavation faces are not retained, the contractor should maintain maximum allowable slopes in accordance with OSHA Regulations (Standards 29 CFR), Part 1926, Subpart P, 'Excavations" (can be found on www.osha.gov). Even with the required OSHA sloping, water seepage or surface runoff can potentially induce sideslope erosion or running which could require slope maintenance. 7.3 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 Page 18 of 19 AMERICAN ENGINEERING TESTING, INC. AET Project No. 01 -04415 ti locations, we recommend on -site observation by a geotechnical engineer /technician during construction to evaluate these potential changes. We also recommend these soils be evaluated for proper through percolation of infiltrating water prior to backfill placement, if the design does not include a perimeter draintile system. Soil density testing should be performed on new fill placed in order to document that project specifications for compaction have been satisfied. 8.0 LIMITATIONS Within the limitations of scope, budget, and schedule, our services have been conducted according to generally accepted geotechnical ' engineering practices at this time and location. Other than this, no warranty, either express or implied, is intended. Important information regarding risk management and proper use of this report is given in Appendix B entitled "Geotechnical Report Limitations and Guidelines for Use ". Page 19 of 19 FLOOR SLAB MOISTUREIVAPOR 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) 302.1R -04, a "base material" is recommended over the vapor membrane, rather than the conventional clean "sand cushion" material. The base layer should be a minimum of 4 inches (100 mm) thick, trimmable, compactible, granular fill (not sand), a so- called crusher -run material. Usually graded from 1' /2 inches to 2 inches (38 to 50 mm) down to rock dust is suitable. Following compaction, the surface can be choked off with a fine -grade material. We refer you to ACI 302.1R -04 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 under floor 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 installation of a vapor membrane to limit the 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: • A lower 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(3/07) 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 arength 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 placementover 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 sinilar 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 include 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 frostmovements 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. O1 REPO 15(02 /01) AMERICAN ENGINEERING TESTING, INC. DEFINITIONS RELATING TO PAVEMENT CONSTRUCTION TOP OF SUBGRADE Grade which contacts the bottom of the aggregate base layer. SAND SUBBASE Uniform thickness sand layer placed as the top of subgrade which is intended to improve the frost and drainage characteristics of the pavement system by better draining excess water in the base /subbase, by reducing and "bridging" frost heaving and by reducing spring thaw weakening effects. CRITICAL SUBGRADE ZONE The subgrade portion beneath and within three vertical feet of the top of subgrade. A sand subbase, if placed, would be considered the upper portion of the critical subgrade zone. GRANULAR BORROW Soils meeting Mn/DOT Specification 3149.2B1. This refers to granular soils which, of the portion passing the 1" sieve, contain less than 20% by weight passing the #200 sieve. SELECT GRANULAR BORROW Soils meeting Mn/DOT Specification 3149.2B2. This refers to granular soils which, of the portion passing the 1" sieve, contain less than 12% by weight passing the #200 sieve. MODIFIED SELECT GRANULAR BORROW CIean, medium grained sands which, of the portion passing the 1" sieve, contain less than 5% by weight passing the #200 sieve and less than 40% by weight passing the #40 sieve. COMPACTION SUBCUT Construction of a uniform thickness subcut below a designated grade to provide uniformity and compaction within the subcut zone. Replacement fill can be the materials subcut, although the reused soils should be blended to a uniform soil condition and recompacted per the Specified Density Method (Mn/DOT Specification 2105.3F1). TEST ROLL A means of evaluating the near - surface stability of subgrade soils (usually non - granular). Suitability is determined by the depth of rutting or deflection caused by passage of heavy rubber -tired construction equipment, such as a loaded dump truck, over the test area. Yielding of less than 1" is normally considered acceptable, although engineering judgment may be applied depending on equipment used, soil conditions present, and /or pavement performance expectations. UNSTABLE SOILS Subgrade soils which do not pass a test roll. Unstable soils typically have water content exceeding the "standard optimum water content" defined in ASTM:D698 (Standard Proctor test). ORGANIC SOILS Soils which have sufficient organic content such that engineering properties /stability are affected. These soils are usually black to dark brown in color. 01REP019 (04/08) AMERICAN ENGINEERING TESTING, INC. Appendix A AET Project No. 01 -04415 Geotechnical Field Exploration and Testing Boring Log Notes Unified Soil Classification System Figure 1 — Boring Locations Figure 2 — Proposed Project Layout Subsurface Boring Logs Appendix A Geotechnical Field Exploration and Testing AET Project No. 01 -04415 A.1 FIELD EXPLORATION The subsurface conditions at the site were explored by drilling and sampling sixteen standard penetration test borings. The locations of the borings appear on Figure 1, preceding the Subsurface Boring Logs in this appendix. A.2 SAMPLING METHODS A.2.1 Split -Spoon Samples (SS) - Calibrated to N60 Values Standard penetration (split - spoon) samples were collected in general accordance with ASTM:D1586 with one primary modification. The ASTM test method consists of driving a 2 -inch O.D. split - barrel sampler into the in -situ soil with a 140 -pound hammer dropped from a height of 30 inches. The sampler is driven a total of 18 inches into the soil. After an initial set of 6 inches, the number of hammer blows to drive the sampler the fmal 12 inches is known as the standard penetration resistance or N- value. Our method uses a modified hammer weight, which is determined by measuring the system energy using a Pile Driving Analyzer (PDA) and an instrumented rod. In the past, standard penetration N -value tests were performed using a rope and cathead for the lift and drop system. The energy g P P Y r�Y transferred to the split -spoon sampler was typically limited to about 60% of it's potential energy due to the friction inherent in this system. This converted energy then provides what is known as an N60 blow count. Most newer drill rigs incorporate an automatic hammer lift and drop system, which has higher energy efficiency and subsequently results in lower N- values than the traditional N60 values. By using the PDA energy measurement equipment, we are able to determine actual energy generated by the drop hammer. With the various hammer systems available, we have found highly variable energies ranging from 55% to over 100 %. Therefore, the intent of AET's hammer calibrations is to vary the hammer weight such that hammer energies lie within about 60% to 65% of the theoretical energy of a 140 -pound weight falling 30 inches. The current ASTM procedure acknowledges the wide variation in N- values, stating that N- values of 100% or more have been observed. Although we have not yet determined the statistical measurement uncertainty of our calibrated method to date, we can state that the accuracy deviation of the N- values using this method is significantly better than the standard ASTM Method. A.2.2 Disturbed Samples (DS) /Spin -up Samples (SU) Sample types described as "DS" or "SU" on the boring logs are disturbed samples, which are taken from the flights of the auger. Because the auger disturbs the samples, possible soil layering and contact depths should be considered approximate. A.2.3 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, and they may be present in the ground even if they are not noted on the boring logs. Determining the thickness of "topsoil" layers is usually limited, due to variations in topsoil definition, sample recovery, and other factors. Visual -manual description often relies on color for determination, and transitioning changes can account for significant variation in thickness judgment. Accordingly, the topsoil thickness presented on the logs should not be the sole basis for calculating topsoil stripping depths and volumes. If more accurate information is needed relating to thickness and topsoil quality definition, alternate methods of sample retrieval and testing should be employed. A.3 CLASSIFICATION METHODS Soil descriptions 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 or Atterberg Limits) have been performed, accurate classifications per ASTM:D2487 are possible. Otherwise, soil descriptions shown on the boring logs are visual -manual judgments. Charts are attached which provide information on the USC system, the descriptive terminology, and the symbols used on the boring logs. The boring logs include descriptions of apparent geology. The geologic depositional origin of each soil layer is interpreted primarily by observation of the soil samples, which can be limited. Observations of the surrounding topography, vegetation, and development can sometimes aid this judgment. Appendix A - Page 1 of 2 AMERICAN ENGINEERING TESTING, INC. Appendix A Geotechnical Field Exploration and Testing AET Project No. 01 -04415 A.4 WATER LEVEL MEASUREMENTS The ground water level 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 - Depth: depth at which measuring tape stops m 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 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. A.5 LABORATORY TEST METHODS A.5.1 Water Content Tests Conducted per AET Procedure 01- LAB -010, which is performed in general accordance with ASTM:D2216 and AASHTO:T265. A.6 TEST STANDARD LIMITATIONS Field and laboratory testing is done in general conformance with the described procedures. Compliance with any other standards referenced within the specified standard is neither inferred nor implied. A.7 SAMPLE STORAGE Unless notified to do otherwise, we routinely retain representative samples of the soils recovered from the borings for a period of 30 days. Appendix A - Page 2 of 2 AMERICAN ENGINEERING TESTING, INC. 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 - Laboratory DS: Disturbed sample from auger flights PL: Plastic Limit, % FA: Flight auger; number indicates outside diameter in q Pocket Penetrometer strength, tsf (approximate) inches q 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: Electrical 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 (expressed (Calibrated Hammer Weight) as percent of the total core run). Zero indicates no The standard penetration test consists of driving a split -spoon sample recovered. sampler with a drop hammer (calibrated weight varies to provide REV: Revert drilling fluid N60 values) and counting the number of blows applied in each of SS: Standard split -spoon sampler (steel; 1%" is inside three 6" increments of penetration. If the sampler is driven less diameter; 2" outside diameter); unless indicated than 18" (usually in highly resistant material), permitted in otherwise ASTM:D1586, the blows for each complete 6" increment and for SU Spin -up sample from hollow stem auger each partial increment is on the boring log. For partial increments, TW: Thin - walled tube; number indicates inside diameter in the number of blows is shown to the nearest 0.1' below the slash. inches WASH: Sample of material obtained by screening returning The length of sample recovered, as shown on the "REC" column, rotary drilling fluid or by which has collected inside may be greater than the distance indicated in the N column. The the borehole after "falling" through drilling fluid disparity is because the N -value is recorded below the initial 6" WH: Sampler advanced by static weight of drill rod and set (unless partial penetration defined in ASTM:D1586 is hammer encountered) whereas the length of sample recovered is for the WR: Sampler advanced by static weight of drill rod entire sampler drive (which may even extend more than 18 "). 94mm: 94 millimeter wireline core barrel Water level directly measured in boring V: Estimated water level based solely on sample appearance 01R.EP052C(01/05) AMERICAN ENGINEERING TESTING, INC. L UNIFIED SOIL CLASSIFICATION SYSTEM AMERICAN A ASTM Designations: D 2487, D2488 ENGINEERING TESTING, INC. nom Soil Classification Notes Criteria for Assigning Group Symbols and Group Names Using Laboratory Test? Group Group Name" "Based on the material passing the 3 -in Symbol (75 -mm) sieve. Coarse - Grained Gravels More Clean Gravels Cu>4 and 1 <Cc <3 GW Well graded gravel' e lf field sample contained cobbles or Soils More than 50% coarse Less than 5% boulders, or both, add "with cobbles or than 50% fraction retained fines Cu <4 and/or I >Cc >3 GP Poorly graded graver boulders, or both" to group name. retained on on No. 4 sieve % Gravels 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 GP -GM poorly graded gravel with silt Sands 50% or Clean Sands Cu >6 and 1 <Cc <3 SW Well- graded sand' GP -GC poorly graded gravel with clay more of coarse Less than 5% ° Sands with 5 to 12% fines require dual fraction passes fines Cu <6 and/or 1 >Cc >3 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 CFI SC Clayey sand "' SP -SC poorly graded sand with clay Fine - Grained Silts and Clays inorganic PI >7 and plots on or above CL Lean clay Soils 50% or Liquid limit less "A" line' (D30) more passes than 50 PI <4 or plots below ML SiIt L M E Cu = Do /D,0 Cc = the No. 200 "A" line D x D60 sieve organic Liquid limit —oven dried <0.75 OL Organic clayK.L.M.N r (see Plasticity Liquid limit— not dried Organic siltK.L "ro If soil contains >15% sand, add "with ( ty g 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 ' M symbol 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 fines" to group name. 'lf soil contains >15% gravel, add "with organic Liquid limit —oven dried <035 01-1 Organic clay"' gravel" to group name. Liquid limit — not dried If Atterberg limits plot is hatched area, Organic SiltK t "to soils is a CL -ML silty clay. Highly organic Primarily organic matter, dark PT Peat'' K If soil contains 15 to 29% plus No. 200 add "with sand" or "with gravel ", soil in color, and organic in odor whichever is predominant. 'If soil contains >30% plus No. 200, SIEVE ANALYSIS ao Hsa «n 00.vq G ", 1 Sm. m.ro.r ---i for d655if�aon of fine- afa,a005os �a predominantly sand, add "sandy" to ftmgeli rrzclon a ooarseora' soih. group name. �3 zm r x x +6 x o eo m zoo - . f 50 _ "' I f soil contains >30% plus No. 200, + �� ■ a Equation of A'4ine Ia+aontalatW- 4tou=u.s , predominantly gravel, add "gravelly" than Plea 73 N- -201 -�. ' 40- to group name. on 111=111101111101111 N LI 2 E uation WV-line AIIIIDIPP 1 ` Vefio ALL= 18 to P1 =7. m '» Pl >4 and plots on or above "A" line. eo , �■■ m than ' °PI <4 or plot below "A" line. PI plots on or above "A" line. '11111111111101 31a� u . , Q PI plots below "A" line. Iao= 25mo 1111' 20 . R Fiber Content description shown below. "1111111111111111110.1-1 , Al, MH or OH 4 -- ������ �� ML or OL w fo 5 1 . 6 05 a+ 00 10 18 20 30 40 30 60 70 80 90 100 110 PARTICLE SIZE IN MWMETERS UQIND LIMIT (LL) —§1 -61-20. 15 .366 C.. IoW' 2'S' S.6 °A ams ob =cti aors.u' 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 Term Particle Size Term 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 4200 sieve Very Stiff 16 - 30 Very Dense Greater than 50 Hard Greater than 30 Moisture/Frost Condition Layering Notes Peat Description Organic Description (if no lab tests) (MC Column) Soils are described as organic, if soil is not peat D (Dry): Absense of moisture, dusty, dry to and is judged to have sufficient organic fines i Laminations: Layers less than Fiber Content touch. content to influence the Liquid Limit properties. /2" thick of Term (Visual Estimate) i ghtly organ used for borderline cases. still have a hi differing material visible. Soil may g Root Inclusions or color. Fibric Peat: Greater than 67% water content (over "optimum "). With roots: Judged to have sufficient quantity W Wet/ Free water visible intended to Hemic Peat: 33 — 67% ( of roots to influence the soil L Waterbearing): describe non - plastic soils. Lenses: Pockets or layers Sapric Peat: Less than 33% properties. Waterbearing usually relates to greater than /z" Trace roots: Small roots present, but not judged sands and sand with silt. thick of differing to be in sufficient quantity to Soil frozen material or color. F (Frozen): significantly affect soil properties. 01CLS021 (07/08) AMERICAN ENGINEERING TESTING, INC. Borings locations: (given in distances from Baselines A & B) #6- 100' W of B, on A #7 - 20' W of B, 22' N of A #8- 223' W of B, 24' N of A ' #9- 178' W of B, 76' N of A #10- 171' WofB, 140'NofA #11- 50' W of B, 179' N of A #12- 16' E of B, 145' N of A #13- 78'EofB, 193'NofA #14- 78'EofB, 117'NofA #15- 118' WofB, 141'NofA 1241 ai i / Baseline B . ----.._____J , .8 i. /. < < j / ,/ 1 \ 1 r 4 //, \ ; #11 �-- 9 � \yam % - ----�' (n 1 \ ��� N 9 r" . #13 <� I II, -- #10 \ � q9 #15 _� \ .99° c / ( ✓ r►- '_ I 6 -c e• / / ,, '7.--- '� , i ,/ / , r 9 I 949 \ ' � L 55r -85 . D 95 1p( �� #3 ,%� A 1 \ #9 1 951.6. , i � 1� 1 \ LIJ �y . � 615,- e Y to _ e e1' en _� 4 /l / 1 O A #8 ; #4 #6 . -A �', So s �\ I X f ' _ _; . " #7 -7._ 1 t . t aseline A \_ 1 ° 1 . ,1 o • 6.' 0 9S e .e EXISTING 1 -STORY BUILDING � 9 sa �� m` n 14158 OAK PARK BLVD. NORTH Xs59, \ \ 89 . ee) ort.t- 6,68/ )1 74. a, 890, , -, 2 64.00 @ 1,1 572.90 ` N89 °35'03 "W X ^1. /.r est wcorner of _ / " I 1 South line of the Northwest Duarte t3 F,'0 S. A. RLS Na 70 r- ,1 .7, 1 r` "" of the Northwest Quarter of Sec. 4, 1 r7 y 1' Point C Twp. 29. Rng. 201 BENCHMARK PA f ,, ' e� e ? y � ► ° TNH =95 Q .- I � (g F FE 9543 'z,�t�� — _ y ' 1 o1i�u iw glir Boring locations: ---------- I - - ` ' b+l #5- 17' E of Point C 9-- �a.,.�� a ,. �r i ,r 4 #16- 9' W & 53' S of Point C = � #16 �,• • ) 2 _ i „, rTl tin of Tract A O @ utility f --- 5 / 1 FT va 70 X5 to r TtlPe�i+a .2 ; T h '� 1 i ' 1 . l v. i I, WETLAND 2 BENCHMARK 1 ' ,._ � ii K _ . 2 K( ' / _ ' & Man .0,—nt ,, TNH= 954.67, 451 . City at Oak Park y r Doc. No 3084037 k' s5 . -- i 5x � 1” PROJECT AET NO City Hall/Public Works Expansion, Oak Park Heights 01 -04415 AMERICAN SUBJECT DATE ENGINEERING Boring Locations TESTING, INC. g December 16, 2008 SCALE DRAWN BY CHECKED BY 1" = 98'± JKV - FIGURE 1 ' , ,/ P �l . W 1 i II 1 F to / I OTR E #7,88 , / ,./ z „,./ / ) \\ i 1 0 / \� 1 1 I 1 1 �/ / EXISTING TREES TO REMAIN \ 1 1 1 I __/ / / ■ 1 / / - 2400 SF 1 1 __-- - -____ / / EXIT AND FUTURE , 72'L' ( 1 - / PATIO EXPANSION'.__ � ° \ '. - ` I .. TREE F -_____I _ / FUTURE \ • 1- - DOOR OPERATOR / EXPANSION { I __---- --"-`� -- / PARKING �' • qTY IMPOUND 9 ENTRY TO LOT ,,,o '" PARKING GARAGE TR 614 „' ! � NEW CITY HALL BUILDING m __ - - " - -- I SLIDING GATE /416.? 1' 13,640 S. F. FOOTPRINT -' - m ENTR WITH FULL LOWER LEVEL 5 i = 6e'.v s'm 1/7 a5• -7 v4• 14•-5 v4• I j I \ •, ■ ___ - - i • 7000 SF .} , ' 6•-0• CONC STEPS 8 ENTRY CANOPY _ / J J , / y ! I FUTURE HANDRAIL I I CONC WALK !� - -/ ` 1I 1 i- PUBLIC GREEN WITH . .._ CAVIL GARDI =.._..._ ® /�- ._.._..� GARDEN LADE I'gFYP, � _.. _.. -.._ _ • : I 9 . ACC. RAMP ,,,,r, WORKS I I �■.�IIh _ -_ _ ._- �.-_ -___ DROPiIFF f..i • WORKS I 1 • I. �� -r BSTALLS _ _ ..�._. ` .-_ _ -_ - -- 4 . - / f Alp GEN ENGL. t6' 0 RAISED PROOF OF PARKING 46%9B , n 1 / / : ' - PAVING CENTER NEW TRAIL 9 - TRAIL TO BE 54 STALLS I BRICK ENCL. w/ / PUBLIC WORKS ' 461 ISLAND wl 10 m REROUTED QSIRFN ' METAL ADDITION BOLIARDS. ------ N ; 1 r n NEW 1 1 I 1 ' - 24 j, PARKIN AND - L ._ ___> --- -- 1 .I -' � ROUNDABOUT 1 L_ ____ T , WORKS EXISTING - - -/ 30 STALLS „�± , 1- BE REMOVED CI LTO 30 EXISTING - -_` - 1 ADDtTiO WORKS °Q CI if I I l GE TO 20 1 S REMAGARAIN 22 STALLS 2 I L ��____ 1 I/�, �2D-0' 3D-0• - - - PROPERTY UNE 1 / ,4 . 1 T PAVING TO BE I T A4 1 1 ' ' 1 ! I • i, `'UU _..._. . _ REMOVED � ` i - EXISTING CITY HALL j , ! � 1 ] , NEW COLONNADE OF TREES ALONG OF I BUILDING TO BE REMOVED 1 ; 1 � ` ' PARKING. SEE LANDSCAPE 1 1 1 4••• NEW CURB 8' CONC h / k v 1 M1 4,. EXISTING RETAINING WALL TO REMAIN • I.' EXISTING CURB TO BE REMOVED SIDEWALK %% L % ��' II -- i `�1ii t i 7 ,� 1 EXISTING CUR ' EXISTING TREES TO REMAIN I �I NIL � TO REMAIN I EXISTING PUMP 61 gl• TOIJ' j ROOM TO REMAIN I L w " H`� �� �i 1 v r 1 ���t: �a4 � ,� , II %U -- 411 1/1111.111%..; ;r — �,s �� O I � X I REMAIN R u _ \ I �lii� { -- EXISTING SI7E \ ; 0 0 O 1 1 0 REMAIN !TENS TO BE I V -:- I 4C. CROSS WALK. TVP. O REMOVED _ - - _ • - --------- - - Oy V O -_ —_-_ FOR REFERENCE - ,-'.\� INDICATE TRAFFIC ' . Q I EXISTING CURS p- _ -_' ., „' �_ _ , 1 ; R.O.W. \ _.� NEW CURB T_� - �V.,1 j .,_ P _ - - - _ �� P P A 16' i --- a VIN - PAVING CENTER , 57TH STREET NORTH ill lj ISLAND w/ 10 • / EXISTING - - ” BOLLARDS. � , 1 TREES T• - 1 'a I NEW CURB \REMAIN a 1 R.O.W. v •-0 1 O 24' ` 26 EXISTING `I 0 10 50 100 STALLS TO REMAIN 1 ` .. n I H I I I i !WI j 1 1 1 • PROJECT AET NO. City Hall/Public Works Expansion, Oak Park Heights 01 -04415 AMERICAN SUBJECT DATE ENGINEERING Proposed Project Layout January 8, 2009 TESTING, INC. SCALE DRAWN BY CHECKED BY 1" = 68 Provided JV FIGURE 2 A AMERICAN ENGINEERING SUBSURFACE BORING LOG MIMS TESTING, INC. AET JOB NO: 01 -03837 LOG OF BORING NO. 1 (p. 1 of 1) PROJECT: City Hall and Public Works Building Expansion; Oak Park Heights, MN DEPTH SURFACE ELEVATION: 951.7 GEOLOGY N MC SAMPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN ' WC DEN LL PL 4�0 -#20( 1 — \ FILL, mostly clayey sand with roots, a little FILL F RI SU gravel, dark brown, frozen ' F/M SU FILL, mostly clayey sand, a little silty sand and 2 — gravel, brown, a little dark brown, frozen to FIA 3 — about 1' 7 M SS 12 14 4 CLAYEY SAND, a little gravel, trace roots, V TILL OR ;1i 5 — brown, stiff (SC) (possible fill) FILL 14 M ' SS 10 7 2 _ SILTY SAND, a little gravel, trace roots, brown, •• TILL 1 medium dense (SM/SC) 30 M " SS 6 8 SILTY SAND, a little gravel, brown, dense to !`i 9 — medium dense (SM) 11i 10 - 45 M1 SS 14 12 — ' • ;$ 13 — 29 M M SS 16 14 — �� 15 — 29 M 0 SS 16 16 — 111 17 — 18 — .. 19 20 42 M it SS 16 21 — ;1/ 22 — 23 _ 29 M ' SS 24 24 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE -IN DRILLING WATER THE ATTACHED 0 - 22' 3.25" HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 1/21/08 1:15 24.0 22.0 24.0 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 1/21/08 DR: SG LG: TM Rig: 91C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG ...... TESTING, INC. AET JOB NO: 01 -03837 LOG OF BORING NO. 2 (p. 1 of 1) PROJECT: City Hall and Public Works Building Expansion; Oak Park Heights, MIN D NTH SURFACE ELEVATION: 952.8 GEOLOGY N MC SAMPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN ' WC DEN LL PL ;4420( 1 - \ 2" FILL, mostly organic sandy silt with roots, FILL F ► SU 33 black to dark brown, frozen / F/M 1 SU 11 FILL, mostly clayey sand with gravel, trace 1 2 - roots, brown, frozen to about 1.25' 3 8 M PA SS 12 10 4 SANDY LEAN CLAY, trace roots, brown, stiff % TILL II 5 — (CL /SC) 10 M 1I SS 10 12 6 / 1 2 SILTY SAND WITH GRAVEL, brown, dense . . 8 — to medium dense (SM) 30 M " SS 12 9 - M 10 - 43 M F SS 14 11 al 12 - 13- 29 M" SS 14 14 - M 15- 32 M SS 16 16 - ]7 - fill 18 - 19 - 20- 19 M RA SS 16 21 - � 22 - \ 1' 23 - 28 M `' SS 24 24 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE -IN DRILLING WATER THE ATTACHED 0 - 22' 3.25" HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 1/21/08 12:10 24.0 22.0 24.0 None SHEETS FOR AN EXPLANATION OF BORING 1/21/08 TERMINOLOGY ON DR: SG LG: TM Rig: 91C THIS LOG 06/04 I A AMERICAN ENGINEERING SUBSURFACE BORING LOG 111111111111111 AET INC. AET JOB NO: 01 -03837 LOG OF BORING NO. 3 (p. 1 of 1) PROJECT: City Hall and Public Works Building Expansion; Oak Park Heights, MN D I T H SURFACE ELEVATION: 955.2 GEOLOGY N MC SAMPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE WC DEN LL PL %-#20( FILL, mostly silty sand, a little gravel, trace FILL F . SU 1 — 1roots, dark brown, frozen 2 FILL, mostly clayey sand, a little silty sand and F/M ill SU 13 gravel, trace roots, brown, frozen to about 1.2' / TILL OR 3 — SANDY LEAN CLAY, a little gravel, trace FILL 6 M A SS 6 18 roots, dark brown to brown, firm (CL /SC) (possible fill) / 0 TILL �1� 4 5 — CLAYEY SAND, a little gravel, brown, stiff 14 M il SS 8 12 6 — (SC/CL) SILTY SAND, a little gravel, brown, dense, 8 — lenses of clayey sand (SM) 36 M �, SS 16 10— 42 M" SS 12 11 — �ii 12 — �1i 13 — 49 M RA SS 16 14 — LA 54 M Pi SS 16 16 — 1 17 — 1 18 — 1.1 19 SAND, a little gravel, possible cobbles, fine to : : COARSE 1 20 — medium grained, brown, moist, very dense (SP) ALLUVIUM * M SS 12 21— 22 1 SILTY SAND, a little gravel, brown, dense TILL 23 — (SM) : 48 M `• SS 18 24 END OF BORING *7/0.5 + 23/0.5 + 50/0.2 DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE -IN DRILLING WATER THE ATTACHED 0 3.25" HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 1/21/08 10:30 24.0 22.0 24.0 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 1/21/08 DR: SG LO: TM Rig: 91C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG ...... IESTING, INC. AET JOB NO: 01 -03837 LOG OF BORING NO. 4 (p. 1 of 1) PROJECT: City Hall and Public Works Building Expansion; Oak Park Heights, MiN DEPTH SURFACE ELEVATION: 953.4 GEOLOGY N MC SAMPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN ' WC DEN LL PL Vo -#t20( FILL, mixture of silty sand and gravel, dark FILL F' • i S(J 1 — brown and brown, frozen / F SU 11 FILL, mixture of clayey sand and sandy lean 111 1 2 — clay, a little silty sand and gravel, brown, frozen 3 — to 2.5' 27 F/M SS 12 12 4 SILTY SAND WITH GRAVEL, brown, dense, . TILL OR 1 5 lenses of clayey sand (SM) (possible fill) FILL 25 M " SS 14 8 6 _ 7 _ SILTY SAND, a little gravel, brown, dense • TILL `il 8 — (SM) 32 M �� SS 14 9 — M 10 — R 34 M SS 16 11 — 12 — � FA 13 — 33 M SS 16 14 !� SILTY SAND WITH GRAVEL, brown, dense 117 15 — (SM) 36 M R. SS 14 16 — A 17 — 1 18— 1 19 — 1 20 — 38 M i SS 14 21— I .•. 22 SAND WITH GRAVEL, fine to medium : -:':-: COARSE l ; 23 — grained, brown, moist, dense, lenses of sandy silt ALLUVIUM 32 M SS 14 24 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE -IN DRILLING WATER THE ATTACHED 0 3.25" HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 1/21/08 9:15 24.0 22.0 24.0 None S HEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 1/21/08 DR: SG LG: TM Rig: 91C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG 111111111111111 TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 5 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN FIELD & LABORATORY TESTS DEPTH SURFACE ELEVATION: 953.4 GEOLOGY N MC SAMPLE REC IN FEET MATERIAL DESCRIPTION TYPE' WC DEN LL PL % - #20( 4.25" Bituminous pavement /---- FILL F/M 1 10" FILL, mostly sand with silt and gravel, dark brown frozen to 10" .FILL '� OR M 2 ..-r FILL SILTY SAND WITH GRAVEL, brown (SM) TILL 20 M SS 14 3 (possible fill) 4 SILTY SAND, a little gravel, brown, a little light ii 5 brown, medium dense, Laminations of sand (SM)/ SILTY SAND, a little gravel, brown, medium 17 M X SS 14 6 dense (SM) 7 8 24 M X SS 12 9 SILTY SAND, a little gravel, brown, a little light t. 10 brown, medium dense, laminations of sand (SM) 21 M X SS 10 11 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE -IN DRILLING WATER THE ATTACHED 0 - 3.25" HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 12/10/08 11:30 11.0 9.5 10.0 None SHEETS FOR AN EXPLANATION OF ' BORING TERMINOLOGY ON COMPLETED: 12/10/08 . THIS LOG DR: EW LG: TK Rig: 66C 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 7 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN DEPTH SURFACE ELEVATION: 952.1 GEOLOGY N MC S 4MPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN' WC DEN LL PL V0-#20( 7" FILL, mixture of silty sand and sandy silt, a FILL 18 1 — little gravel, trace roots, brown and dark brown, `/ TILL 39 F/M X SS 17 frozen / \ 2 — SILTY SAND, a little gravel, brown, medium - 12 M x SS 18 3 — dense, lenses of clayey sand (SM) / \ 4 SILTY SAND, a little gravel, brown, medium :: \ / • 5 — dense, laminations of sand with silt (SM) 16 M X SS 17 — 8 — 18 M SS 15 9 SILTY SAND WITH GRAVEL, brown, dense 10 — (SM) 32 M X SS 16 11 END OF BORING L , DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO �� DATE TIME SAMPLED DEPTH DEPTH FLUID LEVEL LEVEL THE ATTACHED 0 -9Y2 3.25" HSA 12/5/08 12:10 11.0 9.5 11.0 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/5/08 T THIS LOG DR: TK LG: EW Rig: 66C , 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG ammo TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 8 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN DEPTH SURFACE ELEVATION: 949.3 GEOLOGY N MC SAMPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE IN' WC DEN LL PL %-#20( 1 — \ 4" SANDY SILT, trace roots, dark brown, ) \TOPSOIL , \ f 21 froz (ML) / / TILL 10 F/M X SS 14 9 2 CLAYEY SAND, a little gravel, trace roots, _ brown, stiff (SC) 17 M X SS 16 3 — SILTY SAND, a little gravel, brown, medium 4 _.-- O dense (SM) 5 — CLAYEY SAND, a little gravel, trace roots, brown, a little light brown, hard, laminations of / 31 M X SS 16 5 6 — silt (SC) 7 _ SILTY SAND, a Little gravel, brown, a little light : brown, dense, Laminations of silt (SM) 36 M X SS 12 8— li 10 — 46 M x SS 14 11 END OF BORING / • DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO �� DATE TIME SAMPLED CASING TH CAVE-IN DEPTH FLUID LEVEL LEVEL THE ATTACHED 0-9%' 3.25" HSA 12/10/08 10:00 11.0 9.5 10.4 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/10/08 DR: EW LG: TK Rig: 66C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 10 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN DEPNTH SURFACE ELEVATION: 948.9 GEOLOGY N MC SAMPLE REC FIELD & LABORATORY TESTS FEET MATERIAL DESCRIPTION TYPE WC DEN LL PL %-#20( FILL, mostly clayey sand, a little silty sand and FILL , 1 — gravel, trace roots, dark brown and brown, 12 F/M SS 14 12 2 — frozen to about 6" 3 — 17 M :' SS 8 4—+ M 5 _ SILTY SAND, trace roots, fine grained, light ': COARSE brown, moist, medium dense (SM) ALLUVIUM 15 M FA SS 6 6 7 — SILTY SAND, a little gravel, brown, medium TILL It 8 — dense to dense (SM/SC) 23 M A SS 10 8 9 - its i 10 — 32 M :' SS 12 8 11 — M 12 — 13 — 34 M 1 SS 16 7 14 A M SILTY SAND, a little gravel, brown, dense 15 — (SM) 45 M SS 14 16 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO a , �� DATE TIME SAMPLED DEPTH DEPTH FLUID LEVEL LEVEL THE ATTACHED 0-14W 3.25" HSA _ 12/8/08 1:10 16.0 14.5 16.0 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/8/08 _ _ DR: TK LG: EW Rig: 66C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG Now= TESTING, INC. AET JOB NO: 01-04415 LOG OF BORING NO. 12 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN FIELD & LABORATORY TESTS DEPTH SURFACE ELEVATION: 948.0 GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE IN. WC DEN LL PL V0 -#20( 1 — \ 4" SANDY SILT, trace roots, dark brown, ) TOPSOIL 31 frozen (ML) / j MIXED 4 F/M SS 8 13 2 CLAYEY SAND, trace roots, brown, frozen to ALLUVIUM r rik a bout 6 ", then soft (SC) / ' :: TILL 14 M SS 10 3 — SILTY SAND, a little gravel, trace roots, brown, 4 — medium dense to dense, lenses and Laminations : , .: RI of clayey sand (SM) ' 5 — 25 M SS 14 6= `1/ I 8 — 38 M F SS 18 7 • 9 It SAND WITH SILT AND GRAVEL, fine to COARSE 10 — medium grained, brown, moist, dense, a lens of ALLUVIUM 39 M Fl SS 16 11 — silty sand (SP -SM) A 12 — CLAYEY SAND WITH GRAVEL, brown, hard TILL �11 13 — (SC) / . 37 M `r SS 6 10 SILTY SAND WITH GRAVEL, brown, dense �11 15 — (SM) 38 M : SS 18 16 ill 17 — I8 SILTY SAND, a little gravel, brown, dense, 19 — laminations of sand (SM) 1 20 — 38 M F SS 18 21 END OF BORING 4 DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING CAVE -IN DRILLING WATER THE ATTACHED 0 - %z' 3.25" HSA DEPTH DEPTH DEPTH FLUID LEVEL LEVEL 12/9/08 2:10 21.0 19.5 21.0 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/9/08 DR: EW LG: TK Rig: 66C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING No. 13 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN FIELD & LABORATORY TESTS DEIPNTH SURFACE ELEVATION: 948.1 GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE WC DEN LL PL %-#20( 6" SANDY SILT, trace roots, dark brown, 1 1 TOPSOIL ii 32 I frozen (ML) 111 FINE F/M SS 12 12 2 SANDY SILT, trace roots, brown, frozen to ALLUVIUM about 12 ", then moist (ML) TILL . 19 M F SS 6 3 LEAN CLAY WITH SAND, trace roots, light 4 brown, firm (CL) M SILTY SAND, a little gravel, brown, medium 5 dense (SM) 47 M :' SS 16 6 P 7 CLAYEY SAND, a little gravel, possible / " It 8 cobbles at 8', brown, hard, laminations of sand 38 M FA SS 14 7 9 M SILTY SAND WITH GRAVEL, possible 10 cobbles, dense (SM) 32 M FA SS 8 11 . `' 12 SILTY SAND, a little gravel, possible cobbles, :. , : 1 brown, very dense to dense (SM) 53 M'/ SS 14 13 14 ri • • 15 46 M FA SS 16 16 .. I 17 1 • 18 1 19 1 20 43 M " SS 14 21 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED DEP DEPTH FLUID LEVEL LEVEL THE ATTACHED 0-19W 3.25" HSA 12/9/08 12:55 21.0 19.5 20.4 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/9/08 DR: EW LG: TK Rig: 66C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 14 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN FIELD & LABORATORY TESTS DEIPTH SURFACE ELEVATION: 949.5 GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE IN. WC DEN LL PL % - #20( 3" SANDY SILT, with roots, dark brown, frozen \TOPSOIL / 38 1 (ML) ' FINE 4 F/M'l SS 14 11 2 SAND SILT, a little gravel, trace roots, brown, ALLUVIUM `frozen to about 6 ", then moist, very loose (ML) / j TILL 15 M SS 10 6 3 LEAN CLAY WITH SAND, a little gravel, trace A 4 roots, brown, stiff (CL) % `1l i SILTY SAND WITH GRAVEL, brown, 5 medium dense (SM) 20 M : ' SS 12 6 SILTY SAND, a little gravel, brown, medium "" !►]] dense, a lens of clayey sand (SM) /" l 8 SILTY SAND, a little gravel, brown, a little light 27 M SS 10 brown, medium dense, laminations of sand with . 9 silt and sand (SM) /if. `1l 10 SILTY SAND, a little gravel, brown, dense . " F (SM) • • 33 M SS 16 11 l !►ii 12 SILTY SAND WITH GRAVEL, possible 117 cobbles, brown, very dense (SM) 13 . 76 M SS 8 14 SILTY SAND, a little gravel, possible cobbles, 15 brown, very dense (SM/SC) 67 M SS 12 16 1 17 1 18 : , ` 1 19 1 20 56 M p SS 14 21 END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED DEPTH DEPTH FLUID LEVEL LEVEL THE ATTACHED 0 -19/2 3.25" HSA 12/8/08 11:15 21.0 19.5 19.8 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/9/08 DR: EW LG: TK Rig: 66C THIS LOG 06/04 A AMERICAN ENGINEERING SUBSURFACE BORING LOG TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 15 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN FIELD & LABORATORY TESTS DEPTH SURFACE ELEVATION: 950.0 GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE WC DEN LL PL % - #20( FILL, mixture of clayey sand and sandy silt, a FILL \/ 1 – little gravel, trace roots, dark brown, frozen to 11 F/M X SS 8 14 2 about 6" /_\ FILL, mixture of clayey sand and silty sand, a 3 – little gravel, trace roots, brown 13 M SS 12 8 4 – \/ 5 – 18 M X SS 10 10 7 – LEAN CLAY, trace roots, brown and brownish j FINE X t. gray mottled, hard, laminations of silty sand ALLUVIUM 38 M SS 10 9 8 – (CL) 9 SILTY SAND, a little gravel, brown, medium ' TILL X 10 -dense (SM) / Jj25 M SS 12 8 11 CLAYEY SAND, a little gravel, brown, very ;�� stiff (SC) END OF BORING DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO „ DATE TIME SAMPLED CASING EPT DEPTH FLUID LEVEL LEVEL THE ATTACHED 0 -9/: 3.25" HSA 12/8/08 1:55 11.0 9.5 10.7 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/8/08 DR: TK LG: EW Rig: 66C THIS LOG 06/04 A AMERICAN ENGIN SUBSURFACE BORING LOG TESTING, INC. AET JOB NO: 01 -04415 LOG OF BORING NO. 16 (p. 1 of 1) PROJECT: City Hall/Public Works Expansion;Oak Park Heights, MN FIELD & LABORATORY TESTS DEPTH SURFACE ELEVATION: 952.6 GEOLOGY N MC SAMPLE REC FEET MATERIAL DESCRIPTION TYPE IN' WC DEN LL PL V0 -#20( FILL, mixture of clayey sand and silty sand, a FILL - 16 \ / 1 — little gravel, pieces of bituminous, trace roots, F/M X SS 18 dark brown and brown, frozen to 12" / \ 2 ^ CLAYEY SAND, a little gravel, brown, a little V TILL 3 — light brown, very stiff to hard, laminations of 17 M X SS 6 9 a _ sand (SC) fl 5 31 M X SS 10 9 6 — B. 7 — SILTY SAND WITH GRAVEL, brown, \ / medium dense (SM/SC) 16 M x SS 14 8— (` ■ I 9 10 — 29 M X SS 12 11 — _ END OF BORING I 1 I DEPTH: DRILLING METHOD WATER LEVEL MEASUREMENTS NOTE: REFER TO DATE TIME SAMPLED CASING TH CAVE-IN EPTH FLUID LEVEL EVER THE ATTACHED 0-9W 3.25" HSA 12/10/08 12:30 11.0 9.5 10.0 None SHEETS FOR AN EXPLANATION OF BORING TERMINOLOGY ON COMPLETED: 12/10/08 _ DR: EW LG: TK Rig: 66C THIS LOG 06/04 Appendix B AET Project No. 01 -04415 Geotechnical Report Limitations and Guidelines for Use Appendix B Geotechnical Report Limitations and Guidelines for Use AET Project No. 01 -04415 B.1 REFERENCE This appendix provides information to help you manage your risks relating to subsurface problems which are caused by construction delays, cost overruns, claims, and disputes. This information was developed and provided by ASFE', of which, we are a member firm. B.2 RISK MANAGEMENT INFORMATION B.2.1 Geotechnical Services are Performed for Specific Purposes, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical engineering study conducted for a civil engineer may not fulfill the needs of a construction contractor or even another civil engineer. Because each geotechnical engineering study is unique, each geotechnical engineering report is unique, prepared solely for the client. No one except you should rely on your geotechnical engineering report without first conferring with the geotechnical engineer who prepared it. And no one, not even you, should apply the report for any purpose or project except the one originally contemplated. B.2.2 Read the Full Report Serious problems have occurred because those relying on a geotechnical engineering report did not read it all. Do not rely on an executive summary. Do not read selected elements only. B.2.3 A Geotechnical Engineering Report is Based on A Unique Set of Project - Specific Factors Geotechnical engineers consider a number of unique, project - specific factors when establishing the scope of a study. Typically factors include: the client's goals, objectives, and risk management preferences; the general nature of the structure involved, its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specifically indicates otherwise, do not rely on a geotechnical engineering report that was: • not prepared for you, • not prepared for your project, • not prepared for the specific site explored, or • completed before important project changes were made. Typical changes that can erode the reliability of an existing geotechnical engineering report include those that affect: • the function of the proposed structure, as when it's changed from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse, • elevation, configuration, location, orientation, or weight of the proposed structure, • composition of the design team, or • project ownership. Asa general rule, always inform your geotechnical engineer of project changes, even minor ones, and request an assessment of their impact. Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed. B.2.4 Subsurface Conditions Can Change A geotechnical engineering report is based on conditions 'that existed at the time the study was performed. Do not rely on a geotechnical engineering report whose adequacy may have been affected by: the passage of time; by man -made events, such as construction on or adjacent to the site; or by natural events, such as floods, earthquakes, or groundwater fluctuations. Always contact the geotechnical engineer before applying the report to determine if it is still reliable. A minor amount of additional testing or analysis could prevent major problems. I ASFE 8811 Colesville Road /Suite G106, Silver Spring, MD 20910 Telephone: 301/565 -2733: www.asfe.org Appendix B — Page 1 of 2 AMERICAN ENGINEERING TESTING, INC Appendix B Geotechnical Report Limitations and Guidelines for Use AET Project No. 01 -04415 B.2.5 Most Geotechnical Findings Are Professional Opinions Site exploration identified subsurface conditions only at those points where subsurface tests are conducted or samples are taken. Geotechnical engineers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ, sometimes significantly, from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide construction observation is the most effective method of managing the risks associated with unanticipated conditions. B.2.6 A Report's Recommendations Are Not Final Do not overrely on the construction recommendations included in your report. Those recommendations are not final, because geotechnical engineers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual subsurface conditions revealed during construction. The geotechnical engineer who developed your report cannot assume responsibility or liability for the report's recommendations if that engineer does not perform construction observation. B.2.7 A Geotechnical Engineering Report Is Subject to Misinterpretation Other design team members' misinterpretation of geotechnical engineering reports has resulted in costly problems. Lower that risk by having your geotechnical engineer confer with appropriate members of the design team after submitting the report. Also retain your geotechnical engineer to review pertinent elements of the design team's plans and specifications. Contractors can also misinterpret a geotechnical engineering report. Reduce that risk by having your geotechnical engineer participate in prebid and preconstruction conferences, and by providing construction observation. B.2.8 Do Not Redraw the Engineer's Logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering report should never be redrawn for inclusion in architectural or other design drawings. Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk. ‘,, B.2.9 Give Contractors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give contractors the complete geotechnical engineering report, but preface it with a clearly written letter of transmittal. In the letter, advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited; encourage them to confer with the geotechnical engineer who prepared the report (a modest fee may be required) and/or to conduct additional study to obtain the specific types of information they need to prefer. A prebid conference can also be valuable. Be sure contractors have sufficient time to perform additional study. Only then might you be in a position to give contractors the best information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions. B.2.10 Read Responsibility Provisions Closely Some clients, design professionals, and contractors do not recognize that geotechnical engineering is far less exact than other engineering disciplines. This lack of understanding has created unrealistic expectations that have led to disappointments, claims, and disputes. To help reduce the risk of such outcomes, geotechnical engineers commonly include a variety of explanatory provisions in their report. Sometimes labeled "limitations" many of these provisions indicate where geotechnical engineers' responsibilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly. B.2.11 Geoenvironmental Concerns Are Not Covered The equipment, techniques, and personnel used to perform a geoenvironmental study differ significantly from those used to perform a geotechnical study. For that reason, a geotechnical engineering report does not usually relate any geoenvironmental findings, conclusions, or recommendations; e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated environmental problems have led to numerous project failures. If you have not yet obtained your own geoenvironmental information, ask your geotechnical consultant for risk management guidance. Do not rely on an environmental report prepared for someone else. Appendix B — Page 2 of 2 AMERICAN ENGINEERING TESTING, INC