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HomeMy WebLinkAboutBUCKING HORSE SECOND FILING - PDP - PDP120022 - SUBMITTAL DOCUMENTS - ROUND 1 - RECOMMENDATION/REPORTPRELIMINARY GEOTECHNICAL EXPLORATION REPORT BUCKING HORSE DEVELOPMENT – SOUTHEAST (JOHNSON FARM, WORKING FARM, URBAN ESTATE) FORT COLLINS, COLORADO EEC PROJECT NO. 1122025C Prepared for: Bellisimo, Inc. 3702 Manhattan Avenue, Suite 201 Fort Collins, Colorado 80526 Attn: Mr. Gino Campana (gcampana@bellisimo-inc.com) Prepared by: Earth Engineering Consultants, Inc. 4396 Greenfield Drive Windsor, Colorado 80550 PRELIMINARY GEOTECHNICAL EXPLORATION REPORT BUCKING HORSE DEVELOPMENT – SOUTHEAST (JOHNSON FARM, WORKING FARM, URBAN ESTATE) FORT COLLINS, COLORADO EEC PROJECT NO. 1122025C July 19, 2012 INTRODUCTION The preliminary geotechnical exploration you requested for the southeast portion of the Bucking Horse development located north of East Drake Road and east of Timberline Road in Fort Collins, Colorado has been completed. This preliminary exploration includes the Johnson Farm, Working Farm and Urban Estate areas of the development. The approximate areas included in the preliminary exploration completed at this time are indicated on the attached boring location diagram. As requested, a total of ten (10) soil borings were advanced to depths of approximately 15 to 25 feet below present site grades within the planned development area to obtain information on existing subsurface conditions. The approximate locations of those borings are indicated on the attached boring location diagram. The areas evaluated for the preliminary exploration include predominately single-family residential although the working farm area will include several out buildings. Foundation and floor loads for proposed site structures are expected to be light. City of Fort Collins Streets will be constructed for access in this area. We expect small cuts and fills will be required to develop site grades for this portion of the development. The purpose of this report is to describe the subsurface conditions encountered in the test borings, analyze and evaluate the test data and provide preliminary geotechnical considerations for the proposed site development. EXPLORATION AND TESTING PROCEDURES The test boring locations were determined by Bellisimo, Inc. personnel and located in the field by EEC personnel by pacing and estimating angles from identifiable site features. The approximate boring locations are indicated on the attached boring location diagram. The Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 2 locations of the site borings should be considered accurate only to the degree implied by the methods used to make the field measurements. The borings were completed using a truck mounted, CME-45 drill rig equipped with a hydraulic head employed in drilling and sampling operations. The boreholes were advanced using 4-inch nominal diameter continuous flight augers. 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 split barrel and California barrel 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. In the California barrel sampling procedure, relatively undisturbed samples are obtained in removable brass liners. All samples obtained in the field were sealed and returned to the laboratory for further examination, classification and testing. Laboratory moisture content tests were completed on each of the recovered samples. The unconfined compressive strength of appropriate samples was estimated using a calibrated hand penetrometer. Wash sieve analysis and Atterberg limits tests were completed on selected samples to determine the quantity and plasticity of the fines in the subgrade. Swell/consolidation tests were also completed on selected samples to evaluate the soils’ tendency to change volume with variation in moisture content and load. Results of the outlined tests are indicated on the attached boring logs and summary sheets. As a 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 material’s texture and plasticity. The estimated group symbol for 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 Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 3 bedrock was based on visual and tactual observations of disturbed samples and auger cuttings. Coring and/or petrographic analysis may reveal other rock types. SITE AND SUBSURFACE CONDITIONS The Bucking Horse development is located on a triangular parcel on the east side of South Timberline Road, north of Drake Road and southwest of the Great Western Railroad tracks. The southeast portion of this site included as a part of this preliminary exploration is indicated on the attached boring location diagram. Site drainage is generally to the east and north with variable localized drainage. Existing structures from a former farmstead are located on the Johnson Farm area located immediately north of Drake Road. Based on results of the field borings and laboratory testing, subsurface conditions can be generalized as follows. Variable, generally sparse vegetation was encountered at the surface of the boring locations. The vegetation and any associated topsoil were underlain by lean clays with varying amounts of silt and sand. The cohesive soils were generally moderately plastic with low to moderate swell potential measured in laboratory testing. The lean clay soils were generally stiff to very stiff although occasional soft zones were observed at the boring locations. The lean clay soils extended to depths ranging from approximately 2 to 11 feet below present site grades. The deeper zones of sandy clays were observed in the south borings along Drake Road. Lean clays at the other boring locations generally extended to maximum depths on the order of 5 to 6 feet. The lean clay soils were underlain by sands and gravels. The granular soils contained occasional cobbles and were generally medium dense to dense. Those soils extended to depths on the order of 11 to 22 feet below existing ground surface and were underlain by highly weathered claystone bedrock. Borings B-3 and B-4 were terminated at depths of approximately 15 feet in the sands and gravels. Where encountered, the claystone bedrock extended to the bottom of the borings at depths on the order of 15 to 25 feet below present site grades. Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 4 The stratification boundaries indicated on the boring logs represent the approximate locations of changes in soil and bedrock types; in-situ, the transition of materials may be gradual and indistinct. The test borings indicate the subsurface conditions at the boring locations. Subsurface conditions can vary at short distances from the boring locations and across the site. GROUNDWATER OBSERVATIONS Observations were made while drilling and after completion of the borings to detect the presence and depth to hydrostatic groundwater. Free water was observed in borings B-1 through B-8 at depths of approximately 6 feet to 16 feet below present ground surface. Groundwater depths were shallowest along the northeast portion of this site and deeper on the west portion of this site. No free water was observed in borings B-9 and B-10 in the northwest corner of the exploration area extending to depths of approximately 15 to 20 feet below present site grades. Zones of perched and/or trapped water can be encountered in more permeable zones interbedded with the cohesive soils at times throughout the year. Perched water is commonly encountered in soils immediately overlying less permeable bedrock. The location and amount of perched/trapped water can also vary over time depending on variations in hydrologic conditions and other conditions not apparent at the time of this report. Fluctuations in groundwater levels can also occur with variations in hydrologic conditions and other conditions not apparent at the time of this report. Groundwater measurements provided with this report are indicative of groundwater levels at the locations and at the time the borings were completed. ANALYSIS AND RECOMMENDATIONS Swell/Consolidation Test Results Swell/consolidation testing is performed to evaluate the swell or collapse potential of soil or bedrock for determining foundation, floor slab and/or pavement design criteria. In the Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 5 swell/consolidation test, relatively undisturbed samples obtained directly from the California barrel sampler are placed in a laboratory apparatus and inundated with water under a pre- established load. The swell-index is the resulting amount of swell or collapse expressed as a percent of the sample’s initial thickness. After the inundation period, additional incremental loads are applied to evaluate swell pressure and/or consolidation. As a part of this preliminary assessment, we conducted five (5) swell/consolidation tests on near surface samples obtained from the site. The swell index values for the samples analyzed revealed low to moderate swell ranging from approximately 0% to (+) 2.9% at a dead load of 500 psf. The Colorado Association of Geotechnical Engineers (CAGE) uses the following information to provide uniformity in terminology between geotechnical engineers to provide a relative correlation risk performance to measured swell. “The representative percent swell values are not necessarily measured values; rather, they are a judgment of the swell of the soil and/or bedrock profile likely to influence slab performance.” Geotechnical engineers use this information to also evaluate the swell potential risks for foundation performance based on the risk categories. Recommended Representative Swell Potential Descriptions and Corresponding Slab Performance Risk Categories Slab Performance Risk Category Representative Percent Swell (500 psf Surcharge) Representative Percent Swell (1000 psf Surcharge) Low 0 to < 3 0 < 2 Moderate 3 to < 5 2 to < 4 High 5 to < 8 4 to < 6 Very High > 8 > 6 Based on the laboratory test results, the samples analyzed for the Bucking Horse Southeast development were within the low to moderate range. Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 6 General Soil Evaluations The near surface soils, generally above a depth of 5 to 6 feet, are predominately clay soils with varying amounts of silt and sand. The swell potential on those soils varied from essentially no swell to swells in the 2½% to 3% range. Mitigation of the higher swelling materials will likely be required in improvement areas to reduce potential for swelling subgrade soils causing heaving of overlying improvements. The swells measured at two (2) of the test locations exceeded the Larimer County Urban Area Street Standards (LUCASS) swell limit indicating mitigation may be may be required for roadway areas with subgrade soils consisting of the sandy lean clays. Occasional soft or loose zones were observed in the near surface cohesive soils. Mitigation of soft and loose zones should be expected for footing foundations supported within this zone. Mitigation of soft zones may also be required for development of floor slabs or street subgrades. The sandy clay soils transitioned into coarser grain sand and gravel materials at relatively shallow depth at most of the boring locations. Greater depths of sandy clays were observed in the southwest corner of the site. The sands and gravels would show low swell potential and medium dense to dense relative density. Foundations or floor slabs supported directly on the granular soils would be expected to be relatively stable. Free groundwater was observed at depths ranging from approximately 6 to 16 feet below existing site grades with no groundwater observed at the two (2) boring locations in the northwest corner of the site. The deeper groundwater was observed on the west borings while the east borings generally showed shallower groundwater depths. The granular subgrade soil will transmit groundwater relatively rapidly. Fluctuations in groundwater level may occur with variations in in hydrologic conditions in the area. Depth to groundwater should be considered when evaluating possible basement construction in the area and/or areas of cutting and filling for development of site grades. The shallow depths to groundwater may also affect the potential depth for site detention ponds. Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 7 General Site Preparation All existing vegetation and/or topsoil should be removed from building, fill or other improvement areas. In addition, any structures which are razed during the site development should include complete removal of foundations, floor slabs or associated fills and backfills. After stripping and completing all cuts and prior to placement of any fill or structures, the in-place soils should be scarified to a minimum depth of 9 inches, adjusted in moisture content and compacted to at least 95% of the material’s maximum dry density as determined in accordance with ASTM Specification D698, the standard Proctor procedure. The moisture content of the scarified soils should be adjusted to be within the range of ± 2% of standard Proctor optimum moisture content at the time of compaction. Deeper overexcavations and moisture conditioning may be required in some areas to mitigate higher swelling subgrade soils. Swelling subgrade soils allowed to remain beneath roadways, sidewalks and floor slabs or similar improvements could result in post- construction heaving of those improvements with wetting of the subgrade soils. Fill soils required to develop the site grades should consist of approved, low-volume-change materials which are free from organic matter and debris. In general, the site soils could be used as overlot fill materials provided suitable moisture contents are developed in the fill materials at the time of placement and maintained in those fill materials until the overlying improvements are constructed. Care should be taken during fill placement to avoid placing layers or pockets of clean granular materials within the cohesive subgrades to reduce potential for ponding of water at varying locations in the subgrades. In general, site fill materials would be placed in loose lifts not to exceed 9 inches thick, adjusted in moisture content and compacted to at least 95% of the material’s maximum dry density as determined in accordance with the standard Proctor procedure. The moisture content of predominately clay soils should be adjusted to be within the range of ± 2% of optimum moisture content at the time of placement. Granular soils should be adjusted to a workable moisture content. Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 8 Specific explorations should be completed for each building and/or building addition and for specific parking, drive and street areas. Specific exploration for City of Fort Collins streets will be required after pavement subgrades are developed to approximate finish surface elevation and utilities have been installed within the street right-of-ways. Building Foundations We anticipate use of conventional footing foundations could be considered for lightly loaded structures at this site. Footing foundations would be supported either on the native soils or on newly placed and compacted fills. Soft and/or loose zones were observed in the near surface cohesive soils so that care will be necessary to see that foundations are not supported on soft or loose materials. We anticipate footing foundations for site structures could be designed with net allowable total load soil bearing pressures of at least 1,500 psf with possible higher values for foundations supported in the site granular materials. Footings would be supported at least 30 inches below final adjacent exterior grade to provide frost protection. Minimum footing widths are typically recommended in the range of 12 to 16 inches for continuous formed footings and 24 to 30 inches for isolated column foundations. Lateral Earth Pressures Coefficient values for backfill with anticipated types of soils 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. As appropriate, buoyant weights and hydrostatic pressures should be considered. The coefficient values are based on horizontal backfill with backfill soils consisting of either essentially granular materials with a friction angle of 30 degrees or greater or low volume change cohesive soils with a friction angle of at least 25 degrees. Varying backfill materials and/or configurations would result in greater or lesser coefficient values depending on the materials used and final configuration. Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 9 Soil Type On-Site Low Plasticity Cohesive Imported Medium Dense Granular Wet Unit Weight 120 135 Saturated Unit Weight 130 140 Friction Angle () – (assumed) 25° 35° Active Pressure Coefficient 0.41 0.27 At-rest Pressure Coefficient 0.58 0.42 Passive Pressure Coefficient 2.46 3.70 Surcharge loads or point loads placed in the backfill can create additional loads on below grade walls. Those lateral pressures should be evaluated on an individual basis. The outlined lateral earth values do not include factors of safety nor allowances for hydrostatic loads. Care should be taken to develop appropriate drainage systems behind below grade walls to eliminate the potential for hydrostatic loads developing on the walls. Where necessary, appropriate hydrostatic load values should be used for design. Preliminary Pavements Design We anticipate site pavements will be supported on the near surface lean clay soils. Those soils have low support capacity for site pavements. In addition, the cohesive soils at elevated moisture content can show instability and strength loss. In-place stabilization may be required for excessively wet, pumping soils prior to placement of an overlying pavement section. A minimum pavement section of 4 inches of hot bituminous pavement (HBP) overlying 6 inches of aggregate base course (ABC) is required for local streets according to the Larimer County Urban Area Street Standards (LUCASS) for the City of Fort Collins. Thicker pavement sections would be required for higher volume collector or arterial streets. Pavement sections for private drive and parking areas would generally be consistent with the Earth Engineering Consultants, Inc. EEC Project No. 1122025C July 19, 2012 Page 10 LUCASS Standards although heavier traffic loads including delivery drives and driveways for trash trucks may require additional pavement thickness. Concrete pavements could be considered in areas where truck turning traffic would result in excessive lateral stresses on the roadway. If Portland cement concrete pavements are used, a minimum section of 5 inches of Portland cement concrete should be anticipated for drive and parking areas with heavier sections utilized in areas carrying heavier truck traffic or higher volumes. A final pavement evaluation and geotechnical engineering exploration will be required in general accordance with LCUASS Standards after utility infrastructure has been installed and the subgrade section is at or near “final subgrade” elevations. GENERAL COMMENTS The preliminary 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. This report is preliminary in nature and, as such, is not suitable for use in any final design. Site-specific explorations will be required to develop final site-specific recommendations for each of the site buildings and infrastructure in pavements. This report has been prepared for the exclusive use of Bellisimo, 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 are modified or verified in writing by the geotechnical engineer. 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. HARDNESS AND DEGREE OF CEMENTATION: BUCKING HORSE SE FORT COLLINS, COLORADO EEC PROJECT NO. 1122025C JULY 2012 DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ VEGETATION AND TOPSOIL 1 _ _ SANDY LEAN CLAY (CL) 2 brown-reddish, tan _ _ stiff to very stiff 3 dry _ _ 4 _ _ CS 5 21 9000+ 7.8 106.3 34 19 57.2 <500 PSF None _ _ 6 _ _ 7 _ _ 8 _ _ 9 calcareous deposits with depth and traces of gravel _ _ SS 10 5 8000 10.1 _ _ 11 SAND AND GRAVEL _ _ brown, gray, red 12 dense _ _ 13 _ _ 14 _ _ SS 15 50/9" -- 2.4 _ _ 16 _ _ 17 _ _ 18 _ _ 19 CLAYSTONE / SILTSTONE / SANDSTONE _ _ brown, olive,gray, rust SS 20 40 5000 21.7 stiff to very stiff _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ CS 25 50/6" 9000+ 17.5 113.4 BOTTOM OF BORING DEPTH 25' _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ VEGETATION AND TOPSOIL 1 _ _ SANDY LEAN CLAY (CL) 2 brown, calcareous _ _ stiff to very stiff CS 3 25 9000+ 16.3 113.9 42 25 65.7 3000 PSF 2.7% _ _ SAND AND GRAVEL 4 brown, gray, red _ _ loose to dense SS 5 4 -- 16.1 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ SS 10 38 -- 13.4 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ bounce on cobble SS 15 bounce -- 11.2 _ _ 16 _ _ 17 _ _ 18 CLAYSTONE / SILTSTONE / SANDSTONE _ _ brown, olive, gray, rust 19 BOTTOM OF BORING DEPTH 19' _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ VEGETATION AND TOPSOIL 1 _ _ SANDY LEAN CLAY (CL) 2 brown _ _ stiff 3 _ _ 4 SILTY CLAYEY SAND (ML-SC) _ _ brown, red CS 5 5 3000 17.4 107.1 stiff _ _ SAND AND GRAVEL 6 brown, gray, red _ _ medium-dense to dense 7 _ _ 8 _ _ 9 _ _ SS 10 22 -- 9.5 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS 15 46 -- 15.3 _ _ BOTTOM OF BORING DEPTH 15' 16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ SPARSE VEGETATION 1 _ _ SANDY LEAN CLAY (CL) 2 brown _ _ stiff 3 dry _ _ 4 _ _ moist CS 5 10 9000 16.1 107.6 29 12 63 <500 PSF None _ _ 6 soft at 6' _ _ 7 _ _ 8 _ _ 9 _ _ SS 10 6 2000 19.4 _ _ 11 SAND AND GRAVEL _ _ brown, gray, red 12 dense _ _ 13 _ _ 14 _ _ SS 15 36 -- 13.9 _ _ BOTTOM OF BORING DEPTH 15.5' 16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ SPARSE VEGETATION 1 _ _ SANDY LEAN CLAY (CL) 2 brown _ _ medium 3 dry _ _ 4 gravelly seams with depth _ _ moist SS 5 15 2000 3.5 _ _ SAND AND GRAVEL 6 brown, gray, red _ _ dense 7 _ _ 8 _ _ 9 _ _ bounce on cobble SS 10 21/8" -- 12.5 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS 15 37 -- 13.1 _ _ 16 _ _ 17 _ _ 18 _ _ 19 10'+ of cave-in, no drive taken _ _ CLAYSTONE / SILTSTONE / SANDSTONE SS 20 -- 1500 24.8 gray _ _ BOTTOM OF BORING DEPTH 19.5' 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ SPARSE VEGETATION 1 _ _ LEAN CLAY WITH SAND (CL) 2 brown, calcareous _ _ stiff to very stiff CS 3 45 9000+ 9.5 36 20 71.2 <500 PSF None dry _ _ SAND AND GRAVEL 4 brown, gray, red _ _ dense SS 5 36/10" -- 2.2 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ SS 10 34 -- 9.1 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS 15 37 -- 13.1 _ _ 16 _ _ 17 _ _ 18 _ _ 19 12' of cave-in, no drive taken _ _ auger clippings SS 20 -- -- 15.9 _ _ 21 CLAYSTONE / SILTSTONE / SANDSTONE _ _ gray 22 stiff to very stiff _ _ 23 _ _ 24 BOTTOM OF BORING DEPTH 24' _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ SPARSE VEGETATION 1 _ _ SANDY LEAN CLAY (CL) 2 dark brown, calcareous _ _ stiff to very stiff CS 3 20 9000+ 14.8 117.3 moist _ _ 4 _ _ SS 5 10 6000 15.4 _ _ 6 _ _ SAND AND GRAVEL 7 brown, gray, red _ _ dense 8 _ _ 9 _ _ SS 10 26 -- 12.5 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS 15 34/6" -- 13.7 _ _ 16 _ _ 17 _ _ 18 10'+ of cave-in, no drive taken at 19' _ _ CLAYSTONE / SILTSTONE / SANDSTONE 19 gray _ _ BOTTOM OF BORING DEPTH 19' 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ VEGETATION AND TOPSOIL 1 _ _ LEAN CLAY WITH SAND (CL) 2 dark brown, brown _ _ stiff to very stiff 3 moist _ _ 4 _ _ CS 5 23 9000+ 11.9 117.8 36 20 81.2 3600 PSF 2.9% _ _ 6 _ _ 7 _ _ SAND AND GRAVEL 8 brown, gray, red _ _ dense 9 _ _ SS 10 42 -- 11.8 _ _ 11 _ _ 12 _ _ 13 _ _ 14 _ _ SS 15 36 -- 9.8 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ SS 20 30 -- 9.2 _ _ 21 _ _ 22 _ _ CLAYSTONE / SILTSTONE / SANDSTONE 23 gray _ _ stiff to very stiff 24 12' of cave-in, no drive taken at 24' _ _ auger clippings 25 -- 14.5 14.5 BOTTOM OF BORING DEPTH 24' _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ SPARSE VEGETATION 1 _ _ SANDY CLAY (CL) brown, calcareous 2 SAND AND GRAVEL _ _ brown, gray, red 3 dense _ _ 4 bounce on rock _ _ CS 5 8/4" rock -- 2.3 _ _ 6 _ _ 7 _ _ 8 _ _ 9 _ _ no drive taken at 9' - grinding on rock SS 10 -- -- 1.3 _ _ 11 CLAYSTONE / SILTSTONE / SANDSTONE _ _ brown, gray, olive 12 stiff to very stiff _ _ 13 _ _ 14 _ _ SS 15 50/10" 5000 18.4 _ _ 16 _ _ 17 _ _ 18 _ _ 19 _ _ CS 20 50/6" 9000+ 17.7 113.8 BOTTOM OF BORING DEPTH 20' _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL DATE: RIG TYPE: CME45 FOREMAN: DG AUGER TYPE: 4" CFA SPT HAMMER: MANUAL SOIL DESCRIPTION D N QU MC DD -200 TYPE (FEET) (BLOWS/FT) (PSF) (%) (PCF) LL PI (%) PRESSURE % @ 500 PSF _ _ SPARSE VEGETATION 1 _ _ SANDY LEAN CLAY (CL) 2 brown, red, tan, calcareous _ _ stiff to very stiff CS 3 50/11" 9000+ 7.6 120.7 dry _ _ 4 _ _ SS 5 30 6000 6.7 SAND AND GRAVEL _ _ brown, gray, red 6 dense _ _ 7 _ _ 8 _ _ 9 _ _ SS 10 30 7000 10.0 _ _ 11 _ _ 12 _ _ CLAYSTONE / SILTSTONE / SANDSTONE 13 gray _ _ stiff to very stiff 14 _ _ SS 15 30/6" 9000+ 19.2 _ _ BOTTOM OF BORING DEPTH 15' 16 _ _ 17 _ _ 18 _ _ 19 _ _ 20 _ _ 21 _ _ 22 _ _ 23 _ _ 24 _ _ 25 _ _ Earth Engineering Consultants A-LIMITS SWELL SWELL / CONSOLIDATION TEST RESULTS % Swell @ 500: Project: Project #: Date: Material Description: Brown, Reddish Sandy Lean Clay (CL) Sample Location: Boring 1, Sample 1, Depth 4' Liquid Limit: 34 Plasticity Index: 19 % Passing #200: 57.2% Beginning Moisture: 7.8% Dry Density: 92.1 psf Ending Moisture: 24.7% Swell Pressure: < 500 psf None Bucking Horse SE Fort Collins, Colorado 1122025C July 2012 -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) Water Added Consolidation Swell SWELL / CONSOLIDATION TEST RESULTS % Swell @ 500: Project: Project #: Date: Material Description: Brown Calcareous Sandy Lean Clay (CL) Sample Location: Boring 2, Sample 1, Depth 2' Liquid Limit: 42 Plasticity Index: 25 % Passing #200: 65.7% Beginning Moisture: 16.3% Dry Density: 110.9 psf Ending Moisture: 18.1% Swell Pressure: 3000 psf 2.7% Bucking Horse SE Fort Collins, Colorado 1122025C July 2012 -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) Water Added Consolidation Swell SWELL / CONSOLIDATION TEST RESULTS % Swell @ 500: Project: Project #: Date: Material Description: Brown Sandy Lean Clay (CL) Sample Location: Boring 4, Sample 1, Depth 4' Liquid Limit: 29 Plasticity Index: 12 % Passing #200: 63.0% Beginning Moisture: 16.2% Dry Density: 107.6 psf Ending Moisture: 20.6% Swell Pressure: < 500 psf None Bucking Horse SE Fort Collins, Colorado 1122025C July 2012 -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) Water Added Consolidation Swell SWELL / CONSOLIDATION TEST RESULTS % Swell @ 500: Project: Project #: Date: Material Description: Brown, Calcareous Lean Clay with Sand (CL) Sample Location: Boring 6, Sample 1, Depth 2' Liquid Limit: 36 Plasticity Index: 20 % Passing #200: 71.2% Beginning Moisture: 9.5% Dry Density: 92.9 psf Ending Moisture: 22.8% Swell Pressure: < 500 psf None Bucking Horse SE Fort Collins, Colorado 1122025C July 2012 -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) Water Added Consolidation Swell SWELL / CONSOLIDATION TEST RESULTS % Swell @ 500: Project: Project #: Date: Material Description: Dark Brown, Brown Lean Clay with Sand (CL) Sample Location: Boring 8, Sample 1, Depth 4' Liquid Limit: 36 Plasticity Index: 20 % Passing #200: 81.2% Beginning Moisture: 11.9% Dry Density: 117.6 psf Ending Moisture: 16.7% Swell Pressure: 3600 psf 2.9% Bucking Horse SE Fort Collins, Colorado 1122025C July 2012 -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) Water Added Consolidation Swell SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING None SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-10 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING None SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-9 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 9.5' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-8 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 7' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-7 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 9' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-6 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 6.5' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-5 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 12' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-4 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 6' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-3 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 6' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-2 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO SURFACE ELEV N/A 24 HOUR N/A FINISH DATE 7/6/2012 AFTER DRILLING N/A START DATE 7/6/2012 WHILE DRILLING 16' SHEET 1 OF 1 WATER DEPTH LOG OF BORING B-1 PROJECT NO: 1122025C JULY 2012 BUCKING HORSE SE FORT COLLINS, COLORADO 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