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HomeMy WebLinkAboutRIVER DISTRICT BLOCK 8 MIXED-USE - FDP - FDP160025 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTSUBSURFACE EXPLORATION REPORT 360 LINDEN STREET FORT COLLINS, COLORADO EEC PROJECT NO. 1142032 Prepared for: Blue Ocean Enterprises, Inc. 401 Mountain Avenue, Suite 200 Fort Collins, Colorado 80521 Attn: Mr. Brandon Grebe, Construction Manager brandon.grebe@blueocean-inc.com Prepared by: Earth Engineering Consultants, LLC 4396 Greenfield Drive Windsor, Colorado 80550 4396 GREENFIELD DRIVE WINDSOR, COLORADO 80550 (970) 545-3908 FAX (970) 663-0282 EARTH ENGINEERING CONSULTANTS, LLC April 29, 2014 Blue Ocean Enterprises, Inc. 401 Mountain Avenue, Suite 200 Fort Collins, Colorado 80521 Attn: Mr. Brandon Grebe, Construction Manager (brandon.grebe@blueocean-inc.com) Re: Subsurface Exploration Report 360 Linden Street Fort Collins, Colorado EEC Project No. 1142032 Mr. Grebe: Enclosed, herewith, are the results of the geotechnical subsurface exploration completed by Earth Engineering Consultants, LLC (EEC) personnel for the proposed building at 360 Linden Street in Fort Collins, Colorado. In summary, the subsurface materials encountered in the five (5) exploration borings completed on the site generally consisted of approximately 2 to 4½ feet of existing fill overlying native sand and gravel with intermittent apparent cobbles. The native sand and gravel with intermittent cobbles extended to sandstone bedrock at approximate depths of 10 feet below existing site grades. The bedrock extended to the depths explored, approximately 14 to 25 feet. Groundwater was encountered in only one of the soil borings at an approximate depth of 19 feet below site grade at the time of drilling, and 14 feet approximately 24 hours after drilling. Based on results of the field borings and laboratory testing, it is our opinion the proposed building could be supported on a conventional spread footing foundation system bearing on the native granular subsoils, on approved engineered fill material which extends to the native granular subsoils, or on the underlying sandstone bedrock. No foundation should be founded within existing fill materials. Alternative foundation systems could be considered. SUBSURFACE EXPLORATION REPORT 360 LINDEN STREET FORT COLLINS, COLORADO EEC PROJECT NO. 1142032 April 29, 2014 INTRODUCTION The subsurface exploration you requested for the proposed development of 360 Linden Street in Fort Collins, Colorado, has been completed. As a part of that exploration, five (5) soil borings extending to depths of approximately 14 to 25 feet below present site grades were advanced on the development parcel to obtain information on existing subsurface conditions. Individual boring logs and a diagram indicating the approximate boring locations are included with this report. We understand this project involves the construction of a new office/distillery on the referenced parcel. The proposed building will be 2 to 3 stories above grade and will include a full-depth basement. A portion of the structure will house the distillery equipment/process within an approximate 60 foot tall structure. We anticipate maximum wall and column loads for the building would be on the order of 5 klf and 300 kips, respectively, along with light floor loading conditions. Specific information concerning proposed site layout and grading was not available to us at the time of this report. We are basing the recommendations, herein, on assumed cuts and fills of less than 3 feet. The purpose of this report is to describe the subsurface conditions encountered in the five (5) soil borings completed on the site, analyze and evaluate the test data and provide geotechnical recommendations concerning design and construction of the foundations and support of floor slabs. EXPLORATION AND TESTING PROCEDURES The boring locations were established in the field by a representative of Earth Engineering Consultants, LLC (EEC) by pacing and estimating angles from identifiable site features. Those approximate boring locations are indicated on the attached boring location diagram. The locations of the borings should be considerate accurate only to the degree implied by the methods used to make the field measurements. Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 2 The borings were performed using a truck-mounted, CME-55 drill rig equipped with a hydraulic head employed in drilling and sampling operations. The boreholes were advanced using 4-inch nominal continuous flight augers and samples of the subsurface materials encountered were obtained using split-barrel and California barrel sampling procedures in general accordance with ASTM Specifications D1586 and D3550, respectively. In the split barrel and California barrel sampling procedures, standard sampling spoons are driven into the ground by means of a 140-pound hammer falling a distance of 30 inches. The number of blows required to advance the samplers is recorded and is used to estimate the in-situ relative density of cohesionless soils and, to a lesser degree of accuracy, the consistency of cohesive soils and hardness of weathered bedrock. All samples obtained in the field were sealed and returned to our laboratory for further examination, classification and testing. Moisture content tests were completed on each of the recovered samples. The unconfined strength of appropriate samples was estimated using a calibrated hand penetrometer. The quantity and plasticity of the fines in the subgrades were determined by washed sieve analysis and Atterberg limits tests on selected samples. Results of the outlined tests are indicated on the attached boring logs and summary sheets. As part of the testing program, all samples were examined in the laboratory by an engineer and classified in accordance with the attached General Notes and the Unified Soil Classification System, based on the soil’s texture and plasticity. The estimated group symbol for the Unified Soil Classification System is indicated on the boring logs and a brief description of that classification system is included with this report. Classification of the bedrock was based on visual and tactual observation of disturbed samples and auger cuttings. Coring and/or petrographic analysis may reveal other rock types. SITE AND SUBSURFACE CONDITIONS The proposed development lot is located at the south corner of the intersection of Linden Street and Willow Street in Fort Collins. The referenced property is presently open and gravel surfaced with the surrounding properties developed as light industrial. The property is relatively level with less Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 3 than 2 to 3 feet of relief across the sites. Photographs of the site were taken during the subsurface exploration and are included with this report. An EEC field engineer was on site during the drilling operations to evaluate the subsurface conditions encountered and direct the drilling activities. Field logs prepared by EEC site personnel were based on visual and tactual observation of auger cuttings and disturbed samples. The boring logs included with this report may contain modifications to the field logs based on results of laboratory testing and engineering evaluation. Based on results of the field boring and laboratory testing, subsurface conditions can be generalized as follows. Approximately 4 inches of gravel base course material was observed at the surface at the boring locations. The materials below the surfacing generally consisted of fill and apparent fill soils consisting largely of black cinder/coal ash material. The fill soils contained varying zones of cleaner fills. The fill and apparent fill soils generally extended to depths of approximately 2 to 4½ feet below current site grades. The consistency of the fill soils was generally in the medium dense to loose range. The site apparent fill soils were underlain by medium dense to dense native sands and gravels with silts and clay in the nearer surface material. The granular soils were typically tan in color and contained apparent cobbles and variable sand, gravel and fines. The sands and gravels extended to depths of approximately 10 feet and were underlain by sandstone/siltstone bedrock. The bedrock was typically cemented/hard and contained zones of well cemented materials. Auger refusal was encountered in boring B-3 at a depth of approximately 14 feet on apparent well cemented sandstone bedrock. The borings were terminated at depths of approximately 14 to 25 feet in the bedrock materials. The stratification boundaries indicated on the boring logs represent the approximate locations of changes in soil and rock types; in-situ, the transition of materials may be gradual and indistinct. WATER LEVEL OBSERVATIONS Observations were made while drilling and after completion of boring to detect the presence and depth to apparent groundwater. Groundwater was encountered only in boring B-2 at a depth of Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 4 approximately 19 feet as the boring was being advanced and rising to a depth of approximately 14 feet the day after drilling. The boreholes were backfilled the day after completion of the drilling operation; therefore subsequent groundwater measurements were not obtained. Fluctuations in groundwater levels can occur over time depending on variations in hydrologic conditions and other conditions not apparent at the time of this report. In addition, zones of perched and/or trapped water may be encountered at times throughout the year in more permeable areas within the subgrade materials. Perched water is commonly observed in more permeable soils overlying lower permeability bedrock. The location and amount of perched water can also vary over time depending on variations in hydrologic conditions and other conditions not apparent at the time of this report. ANALYSIS AND RECOMMENDATIONS General Considerations Precautions will be required in the design and construction of the new building and any new pavements to address the existing fill material, the removal/excavation of cobbles at increased depths, penetration of the underlying well cemented sandstone bedrock lenses, and shoring/protection of adjacent properties during excavation for the proposed basement level of site. It is anticipated that excavations for the proposed construction can be accomplished with conventional earthmoving equipment. However, if excavations penetrating the well-cemented sandstone bedrock are required, the use of specialized heavy-duty equipment such as a rock hammer or core barrel to achieve final design elevations may be necessary. Consideration should be given to obtaining a unit price for difficult excavation in the contract documents for the project. Depending upon the depth and proximity to the property line of lower level construction, a shoring plan may be necessary to protect the adjacent sidewall slopes. The project design team should use the subsurface information provided herein to properly design a mechanism for shoring protection. EEC is available to provide supplemental design criteria or details, such as but not limited to secant piles or piers, soldier piers, or a tie-back/bracing concepts. Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 5 Site Preparation Final site grades were not available at the time of this report. We are basing the recommendations in this report on an assumption that cuts and fills of less than 2 to 3 feet will be necessary to achieve design grades with the exception of the basement portions of the building where deeper excavations will be required. All of the existing fill material should be removed in the new building areas including adjacent flatwork areas. The in-place fill material does not appear to be acceptable for use as any site fill. In-place fill materials could probably remain in pavement and landscape areas with an acknowledgement that some future settlement could occur in the remaining fill areas and that future settlement could result in differential movements in the overlying improvements. After stripping, over-excavating as necessary and completing all cuts, and prior to placement of any fill material or site improvements, we recommend the exposed subsoils be scarified to a minimum depth of 9-inches, adjusted in moisture content to within ±3% of standard Proctor optimum moisture content, and compacted to at least 98% of the material's standard Proctor maximum dry density as determined in accordance with ASTM Specification D698. If cuts extend into zones of cinder and/or ash fill, scarification and recompaction would generally not be possible. Removal and replacement of unstable zones of cinder/ash fill may be necessary in near surface subgrades in all areas not specifically designated as landscaping. Fill soils required to develop the building, pavement and site subgrades, after the initial subgrade zone (i.e. the layer beneath any over-excavation requirements) has been stabilized, should consist of approved, low-volume-change materials which are free from organic matter and debris. We recommend structural fill materials be placed and compacted within the building footprint and consist of essentially granular soils. Silty and/or clayey sands or underlying sands and gravels excluding cobble sized material could be used for fill in these areas. We recommend fill materials be placed in loose lifts not to exceed 9 inches thick and adjusted in moisture content to within ± 3% of optimum moisture content, and compacted to at least 98% of the material’s maximum dry density as determined in accordance with ASTM Specification D698, the standard Proctor procedure. Care should be exercised after preparation of the subgrades to avoid disturbing the subgrade materials. Positive drainage should be developed away from the structure to avoid wetting of Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 6 subgrade materials. Subgrade materials becoming wet subsequent to construction of the site structure can result in unacceptable performance. Foundations – Conventional Type Spread Footings Based on results of field borings and laboratory testing as outlined in this report, it is our opinion the proposed building could be supported on conventional type spread footing foundations bearing on the native granular stratum, on a zone of engineered fill material extending to the native granular soils, or extending to the underlying sandstone bedrock. In no case should any foundation system be placed on the existing on-site fill material. Footings bearing on approved native granular subsoils or on engineered fill material extended to the granular strata could be designed for a maximum net allowable total load soil bearing pressure of 2,500 psf. Footing foundations extending to the sandstone bedrock could be designed using a net allowable total load soil bearing pressure not to exceed 5,000 psf. The net bearing pressure refers to the pressure at foundation bearing level in excess of the minimum surrounding overburden pressure. Total load includes full dead and live loads. A minimum dead load pressure would not be required in the low swell potential subsoils and bedrock. If fill material is required to achieve foundation bearing elevations, the engineered fill material should consist of structural fill placed in uniform lifts, properly moisture conditioned, and compacted to at least 98% of standard Proctor density (ASTM D698). Overexcavation for placement of the structural fill should extend to the native granular subsoils, and should extend at least eight (8) inches beyond the edges of the foundations for each 12 inches of structural fill placed beneath the footings. Exterior footings and foundations in unheated areas must be protected from frost action. The normal depth of frost protection in this location is a minimum depth of 30 inches. Continuous wall footings generally have a width of at least 12 inches. Isolated column pads generally require dimensions of at least 24 inches by 24 inches. Footings should be proportioned to reduce differential foundation movement. Proportioning on the basis of equal total settlement is recommended; however, proportioning to relative constant dead-load pressure will also reduce differential settlement between adjacent footings. Total settlement resulting from the assumed structural loads is estimated to be on the order of 1 inch or less. Differential settlement is estimated to be on the order of 1/2 of the Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 7 estimated total settlement. Additional foundation movements could occur if water from any source infiltrates the foundation soils; therefore, proper drainage should be provided in the final design and during construction. Care should be taken during construction to see that the footing foundations are supported on similar, suitable strength native subsoils, approved fill material or suitable sandstone bedrock. Extra care should be taken in evaluating the in-place soils with potentially variable depths of in-place fill across the site. If unacceptable materials are encountered at the time of construction, it may be necessary to extend the footing foundations to bear below the unacceptable materials or removal and replacement of a portion or all of the unacceptable materials may be required. Those conditions can best be evaluated in open excavations at the time of construction. No unusual problems are anticipated in completing the excavation required for construction of the footing foundations. Care should be taken during construction to avoid disturbing the foundation bearing materials. Materials which are loosened or disturbed by the construction activities or materials which become dry and desiccated or wet and softened should be removed and replaced prior to placement of foundation concrete. Seismic The site soil conditions consist of approximately 10 feet of overburden granular subsoils overlying cemented to well-cemented sandstone bedrock. For those site conditions, the 2009 International Building Code indicates a Seismic Site Classification of C. Lateral Earth Pressures The proposed building will include at least a partial full-depth basement as a part of the new building. Site retaining walls may also be desirable with the grade changes across the site. Basement walls of the building and/or site retaining walls would be subjected to unbalanced lateral earth pressures. Passive lateral earth pressures may help resist the driving forces for retaining wall or other similar site structures. The values presented herein are for approved material placed and compacted adjacent to the site structures. Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 8 Active lateral earth pressures could be used for design of structures where some movement of the structure is anticipated, such as retaining walls. The total deflection of structures for design with active earth pressure is estimated to be on the order of one half of one percent of the height of the down slope side of the structure. We recommend at-rest pressures be used for design of structures where rotation of the walls is restrained, such as basement walls. Passive pressures and friction between the footing and bearing soils could be used for design of resistance to movement of retaining walls. Coefficient values for backfill with the anticipated types of fill/backfill soil for calculation of active, at rest and passive earth pressures are provided in the table below. Equivalent fluid pressure is equal to the coefficient times the appropriate soil unit weight. Those coefficient values are based on horizontal backfill with backfill soils consisting of essentially granular materials with a friction angle of 30 degrees. For the at-rest and active earth pressures, slopes down and away from the structure would result in reduced driving forces with slopes up and away from the structures resulting in greater forces on the walls. The passive resistance would be reduced with slopes away from the wall. The top 30 inches of soil on the passive resistance side of walls could be used as a surcharge load; however, should not be used as a part of the passive resistance value. Frictional resistance is equal to the tangent of the friction angle times the normal force. Surcharge loads or point loads placed in or on the backfill can also create additional loads on below grade walls. Those situations should be designed on an individual basis. Soil Type – ONLY FOR APPROVED MATERIALS Medium Dense Granular – On-site or Approved Imported Fill Wet Unit Weight (pcf) 135 Saturated Unit Weight (pcf) 140 Friction Angle () – (assumed) 30° Active Pressure Coefficient 0.33 At-rest Pressure Coefficient 0.50 Passive Pressure Coefficient 3.00 The outlined values do not include factors of safety nor allowances for hydrostatic loads and are based on assumed friction angles, which should be verified after potential material sources have been identified. Care should be taken to develop appropriate drainage systems behind below grade Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 9 walls to eliminate potential for hydrostatic loads developing on the walls. Those systems would likely include perimeter drain systems extending to sump areas or free outfall where reverse flow cannot occur into the system. Where necessary, appropriate hydrostatic load values should be used for design. Floor Slab Subgrades All existing vegetation/topsoil and/or existing pavement and associated site fill materials should be removed from beneath the new building at-grade floor slab area(s). The subgrades should be prepared as outlined under “Site Preparation” in this report. Floors could be supported directly on the placed structural fill soils. After preparation of the subgrades, care should be taken to avoid disturbing the subgrade materials. Materials which are loosened or disturbed by the construction activities will require removal and replacement or reworking in place prior to placement of the overlying floor slabs. Positive drainage should be developed away from the proposed building addition to avoid wetting the subgrade or bearing materials. Subgrade or bearing materials allowed to become wetted subsequent to construction can result in unacceptable performance of the improvements. Other Considerations Positive drainage should be developed away from the structure and pavement areas with a minimum slope of 1 inch per foot for the first 10 feet away from the improvements in landscape areas. Care should be taken in planning of landscaping adjacent to the building and parking and drive areas to avoid features which would pond water adjacent to the pavement, foundations or stemwalls. Placement of plants which require irrigation systems or could result in fluctuations of the moisture content of the subgrade material should be avoided adjacent to site improvements. Lawn watering systems should not be placed within 5 feet of the perimeter of the building and parking areas. Spray heads should be designed not to spray water on or immediately adjacent to the structure or site pavements. Roof drains should be designed to discharge at least 5 feet away from the structure and away from the pavement areas. Earth Engineering Consultants, LLC EEC Project No. 1142032 April 29, 2014 Page 10 Excavations into the on-site soils may encounter a variety of conditions. Excavations extending into the on-site fill zone and native granular strata may encounter loose and caving conditions. The individual contractor(s) should be made responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom and taking into account the site subsurface conditions as described herein. All excavations should be sloped or shored in the interest of safety following local and federal regulations, including current OSHA excavation and trench safety standards. GENERAL COMMENTS The analysis and recommendations presented in this report are based upon the data obtained from the soil borings performed at the indicated locations and from any other information discussed in this report. This report does not reflect any variations which may occur between borings or across the site. The nature and extent of such variations may not become evident until further exploration or construction. If variations appear evident, it will be necessary to re-evaluate the recommendations of this report. It is recommended that the geotechnical engineer be retained to review the plans and specifications so that comments can be made regarding the interpretation and implementation of our geotechnical recommendations in the design and specifications. It is further recommended that the geotechnical engineer be retained for testing and observations during earthwork and foundation construction phases to help determine that the design requirements are fulfilled. This report has been prepared for the exclusive use for representatives with Blue Ocean Enterprises, Inc., for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranty, express or implied, is made. In the event that any changes in the nature, design or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless the changes are reviewed and the conclusions of this report modified or verified in writing by the geotechnical engineer. Earth Engineering Consultants, LLC DRILLING AND EXPLORATION DRILLING & SAMPLING SYMBOLS: SS: Split Spoon ‐ 13/8" I.D., 2" O.D., unless otherwise noted PS: Piston Sample ST: Thin‐Walled Tube ‐ 2" O.D., unless otherwise noted WS: Wash Sample R: Ring Barrel Sampler ‐ 2.42" I.D., 3" O.D. unless otherwise noted PA: Power Auger FT: Fish Tail Bit HA: Hand Auger RB: Rock Bit DB: Diamond Bit = 4", N, B BS: Bulk Sample AS: Auger Sample PM: Pressure Meter HS: Hollow Stem Auger WB: Wash Bore Standard "N" Penetration: Blows per foot of a 140 pound hammer falling 30 inches on a 2‐inch O.D. split spoon, except where noted. WATER LEVEL MEASUREMENT SYMBOLS: WL : Water Level WS : While Sampling WCI: Wet Cave in WD : While Drilling DCI: Dry Cave in BCR: Before Casing Removal AB : After Boring ACR: After Casting Removal Water levels indicated on the boring logs are the levels measured in the borings at the time indicated. In pervious soils, the indicated levels may reflect the location of ground water. In low permeability soils, the accurate determination of ground water levels is not possible with only short term observations. DESCRIPTIVE SOIL CLASSIFICATION Soil Classification is based on the Unified Soil Classification system and the ASTM Designations D‐2488. Coarse Grained Soils have move than 50% of their dry weight retained on a #200 sieve; they are described as: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are described as : clays, if they are plastic, and silts if they are slightly plastic or non‐plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse grained soils are defined on the basis of their relative in‐ place density and fine grained soils on the basis of their consistency. Example: Lean clay with sand, trace gravel, stiff (CL); silty sand, trace gravel, medium dense (SM). CONSISTENCY OF FINE‐GRAINED SOILS Unconfined Compressive Strength, Qu, psf Consistency < 500 Very Soft 500 ‐ 1,000 Soft 1,001 ‐ 2,000 Medium 2,001 ‐ 4,000 Stiff 4,001 ‐ 8,000 Very Stiff 8,001 ‐ 16,000 Very Hard RELATIVE DENSITY OF COARSE‐GRAINED SOILS: N‐Blows/ft Relative Density 0‐3 Very Loose 4‐9 Loose 10‐29 Medium Dense 30‐49 Dense 50‐80 Very Dense 80 + Extremely Dense PHYSICAL PROPERTIES OF BEDROCK DEGREE OF WEATHERING: Slight Slight decomposition of parent material on joints. May be color change. Moderate Some decomposition and color change throughout. High Rock highly decomposed, may be extremely broken. Group Symbol Group Name Cu≥4 and <Cc≤3 E GW Well‐graded gravel F Cu<4 and/or 1>Cc>3 E GP Poorly‐graded gravel F Fines classify as ML or MH GM Silty gravel, G,H Fines Classify as CL or CH GC Clayey Gravel F,G,H Cu≥6 and 1<Cc≤3 E SW Well‐graded sand 1 Cu<6 and/or 1>Cc>3 E SP Poorly‐graded sand 1 Fines classify as ML or MH SM Silty sand G,H,I Fines classify as CL or CH SC Clayey sand G,H,I inorganic PI>7 and plots on or above "A" Line CL Lean clay K,L,M PI<4 or plots below "A" Line ML Silt K,L,M organic Liquid Limit ‐ oven dried Organic clay K,L,M,N Liquid Limit ‐ not dried Organic silt K,L,M,O inorganic PI plots on or above "A" Line CH Fat clay K,L,M PI plots below "A" Line MH Elastic Silt K,L,M organic Liquid Limit ‐ oven dried Organic clay K,L,M,P Liquid Limit ‐ not dried Organic silt K,L,M,O Highly organic soils PT Peat (D30) D x D GW‐GM well graded gravel with silt NPI≥4 and plots on or above "A" line. GW‐GC well‐graded gravel with clay OPI≤4 or plots below "A" line. GP‐GM poorly‐graded gravel with silt PPI plots on or above "A" line. GP‐GC poorly‐graded gravel with clay QPI plots below "A" line. SW‐SM well‐graded sand with silt SW‐SC well‐graded sand with clay SP‐SM poorly graded sand with silt SP‐SC poorly graded sand with clay Earth Engineering Consultants, LLC IIf soil contains >15% gravel, add "with gravel" to group name JIf Atterberg limits plots shaded area, soil is a CL‐ ML, Silty clay Gravels with Fines more than 12% fines Clean Sands Less than 5% fines Sands with Fines 360 LINDEN STREET FORT COLLINS, COLORADO EEC PROJECT NO. 1142032 APRIL 2014 DATE: RIG TYPE: CME55 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: AUTOMATIC SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF GRAVEL - 4" _ _ 1 FILL: Miscellaneous Soil with Cinders & Apparent Coal Ash _ _ black / brown 2 with coal chunks _ _ 3 _ _ 4 _ _ CS 5 9 4000 8.9 115.9 CLAYEY SAND (SC) _ _ brown, medium dense to loose 6 _ _ 7 SAND & GRAVEL (SP/GP) _ _ brown 8 medium dense _ _ 9 _ _ SS 10 50/10" -- 1.8 _ _ SANDSTONE / SILTSTONE 11 brown / rust _ _ poorly cemented to cemented 12 with intermittent well cemented lenses _ _ 13 _ _ 14 _ _ CS 15 50/1" -- 10.4 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ grey SS 20 50/0.5" 9000+ 14.3 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ CS 25 50/0.5" 9000+ 11.8 BOTTOM OF BORING DEPTH 25.0' _ _ Earth Engineering Consultants, LLC A-LIMITS SWELL DATE: RIG TYPE: CME55 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: AUTOMATIC SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF GRAVEL - 4" _ _ 1 FILL: Miscellaneous Soil with Cinders & Apparent Coal Ash _ _ brown / black 2 _ _ 3 _ _ 4 _ _ CLAYEY SAND (SC) CS 5 9 8500 10.9 121.2 <500 psf None brown _ _ medium dense to loose 6 _ _ 7 _ _ 8 1' gravel seam _ _ 9 _ _ SS 10 50/7" -- 10.3 SANDSTONE _ _ brown / rust 11 poorly cemented to cemented _ _ with intermittent well cemented zones 12 _ _ 13 _ _ 14 grey _ _ CS 15 50/1" 9000+ 12.3 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS 20 50/2" 9000+ 14.9 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ CS 25 50/0.5" 9000+ 9.4 BOTTOM OF BORING DEPTH 25.0' _ _ Earth Engineering Consultants, LLC A-LIMITS SWELL DATE: RIG TYPE: CME55 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: AUTOMATIC SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF GRAVEL - 4" _ _ 1 FILL - Miscellaneous Soil with Cinders & Apparent Coal As _ _ brown / black 2 _ _ CLAYEY SAND (SC) CS 3 7 3500 7.5 116.0 brown _ _ medium dense to loose 4 _ _ SS 5 4 6000 8.9 _ _ 6 _ _ SAND & GRAVEL (SP/GP) 7 brown _ _ medium dense 8 _ _ 9 _ _ CS 10 50/5" -- 3.8 _ _ SANDSTONE/SILTSTONE 11 brown / rust _ _ poorly cemented to cemented 12 _ _ 13 _ _ 14 BOTTOM OF BORING DEPTH 14.0' _ _ Auger Refusal on Apparent Well Cemented SS 15 Bounce 9000+ 12.4 Sandstone _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants, LLC A-LIMITS SWELL DATE: RIG TYPE: CME55 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: AUTOMATIC SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF GRAVEL - 4" _ _ 1 FILL - Miscellaneous Soil with Cinders & Apparent Coal As _ _ brown / black 2 _ _ 3 _ _ 4 _ _ CLAYEY SAND (SC) CS 5 10 7500 11.8 120.0 brown, medium dense _ _ 6 SAND & GRAVEL (SP/GP) _ _ brown 7 medium dense _ _ 8 _ _ 9 _ _ SS 10 50 -- 1.9 _ _ 11 SANDSTONE/SILTSTONE _ _ brown / rust 12 poorly cemented to cemented _ _ 13 _ _ 14 _ _ with intermittent well cemented lenses CS 15 -- _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ grey SS 20 50/0.5" 9000+ 13.8 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ CS 25 50/0.5" BOTTOM OF BORING DEPTH 25.0' _ _ Earth Engineering Consultants, LLC A-LIMITS SWELL DATE: RIG TYPE: CME55 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: AUTOMATIC SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ FILL: LEAN CLAY (CL) with Apparent Cinders & Coal Ash 1 brown / black _ _ 2 _ _ CS 3 10 9000+ 11.7 113.8 _ _ 4 _ _ CLAYEY GRAVEL, brown, medium dense SS 5 34 6000 14.3 _ _ SAND & GRAVEL (SP/GP) 6 brown _ _ medium dense 7 _ _ 8 _ _ 9 _ _ CS 10 50/8" -- 1.1 132.4 _ _ SANDSTONE 11 grey / olive _ _ poorly cemented to cemented 12 with intermittent well cemented zones _ _ 13 _ _ 14 _ _ SS 15 50/3" 9000+ 14.0 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ CS 20 50/1.5" 9000+ 13.7 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ SS 25 50/1.5" 9000+ 13.7 BOTTOM OF BORING DEPTH 25.5' _ _ Earth Engineering Consultants, LLC A-LIMITS SWELL Project: Location: Project #: Date: 360 Linden Street Fort Collins, Colorado 1142032 April 2014 Beginning Moisture: 10.9% Dry Density: 121.2 pcf Ending Moisture: 12.8% Swell Pressure: <500 psf % Swell @ 500: None Sample Location: Boring 2, Sample 1, Depth 4' Liquid Limit: Plasticity Index: % Passing #200: SWELL / CONSOLIDATION TEST RESULTS Material Description: Brown Clayey Sand (SC) -10.0 -8.0 -6.0 -4.0 -2.0 0.0 2.0 4.0 6.0 8.0 10.0 0.01 0.1 1 10 Percent Movement Load (TSF) Consolidatio Swell Water Added SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 4/16/2014 AFTER DRILLING N/A SHEET 1 OF 1 WATER DEPTH START DATE 4/16/2014 WHILE DRILLING None 360 LINDEN STREET FORT COLLINS, COLORADO PROJECT NO: 1142032 LOG OF BORING B-5 APRIL 2014 SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 4/16/2014 AFTER DRILLING N/A SHEET 1 OF 1 WATER DEPTH START DATE 4/16/2014 WHILE DRILLING None 360 LINDEN STREET FORT COLLINS, COLORADO PROJECT NO: 1142032 LOG OF BORING B-4 APRIL 2014 SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 4/16/2014 AFTER DRILLING N/A SHEET 1 OF 1 WATER DEPTH START DATE 4/16/2014 WHILE DRILLING None 360 LINDEN STREET FORT COLLINS, COLORADO PROJECT NO: 1142032 LOG OF BORING B-3 APRIL 2014 SURFACE ELEV N/A 24 HOUR 14.0' FINISH DATE 4/16/2014 AFTER DRILLING N/A SHEET 1 OF 1 WATER DEPTH START DATE 4/16/2014 WHILE DRILLING 19.0' 360 LINDEN STREET FORT COLLINS, COLORADO PROJECT NO: 1142032 LOG OF BORING B-2 APRIL 2014 SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 4/16/2014 AFTER DRILLING N/A SHEET 1 OF 1 WATER DEPTH START DATE 4/16/2014 WHILE DRILLING None 360 LINDEN STREET FORT COLLINS, COLORADO PROJECT NO: 1142032 LOG OF BORING B-1 APRIL 2014 more than 12% fines HIf fines are organic, add "with organic fines" to group name LIf soil contains ≥ 30% plus No. 200 predominantly sand, add "sandy" to group name. MIf soil contains ≥30% plus No. 200 predominantly CGravels with 5 to 12% fines required dual symbols: gravel, add "gravelly" to group name. UNIFIED SOIL CLASSIFICATION SYSTEM Soil Classification Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Sands 50% or more coarse fraction passes No. 4 sieve Fine‐Grained Soils 50% or more passes the No. 200 sieve <0.75 Kif soil contains 15 to 29% plus No. 200, add "with sand" or "with gravel", whichever is predominant. OL <0.75 OH Primarily organic matter, dark in color, and organic odor ABased on the material passing the 3‐in. (75‐mm) sieve ECu=D60/D1 Cc= Silts and Clays Liquid Limit less than 50 Silts and Clays Liquid Limit 50 or more Clean Gravels Less than 5% fines Gravels more than 50% of coarse fraction retained on No. 4 sieve Coarse ‐ Grained Soils more than 50% retained on No. 200 sieve DSands with 5 to 12% fines require dual symbols: BIf field sample contained cobbles or boulders, or both, add "with cobbles or boulders, or both" to group name. FIf soil contains ≥15% sand, add "with sand" to GIf fines classify as CL‐ML, use dual symbol GC‐ CM, or SC‐SM. 0 10 20 30 40 50 60 0102030405060708090100110 PLASTICITY INDEX (PI) LIQUID LIMIT (LL) ML OR OL MH OR OH For Classification of fine‐grained soils and fine‐grained fraction of coarse‐grained soils. Equation of "A"‐line Horizontal at PI=4 to LL=25.5 then PI‐0.73 (LL‐20) Equation of "U"‐line Vertical at LL=16 to PI‐7, then PI=0.9 (LL‐8) CL‐ML HARDNESS AND DEGREE OF CEMENTATION: Limestone and Dolomite: Hard Difficult to scratch with knife. Moderately Can be scratched easily with knife. Hard Cannot be scratched with fingernail. Soft Can be scratched with fingernail. Shale, Siltstone and Claystone: Hard Can be scratched easily with knife, cannot be scratched with fingernail. Moderately Can be scratched with fingernail. Hard Soft Can be easily dented but not molded with fingers. Sandstone and Conglomerate: Well Capable of scratching a knife blade. Cemented Cemented Can be scratched with knife. Poorly Can be broken apart easily with fingers. Cemented