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Home My WebLink AboutWELLS FARGO PARKING LOT AND ATMS - FDP200016 - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTSoilogic, Inc. 3050 67th Avenue, Suite 200  Greeley, CO 80634  (970) 535-6144 P.O. Box 1121  Hayden, CO 81639  (970) 276-2087 August 11, 2016 Quality Engineering, LLC 2637 Midpoint Drive, Suite E Fort Collins, Colorado 80234 Attn: Mr. Cody Geisendorfer, P.E. Re: Geotechnical Subsurface Exploration and Pavement Section Design Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic Project # 16-1181 Mr. Geisendorfer: Soilogic, Inc. (Soilogic) personnel have completed the geotechnical subsurface exploration you requested for the proposed Wells Fargo parking lot to be constructed northwest of the intersection of West Magnolia Street and North College Avenue, at 112 West Magnolia Street in Fort Collins, Colorado. The results of our subsurface exploration and pertinent geotechnical engineering recommendations are included with this report. We understand this project involves the construction of a parking lot at the above referenced site in Fort Collins, Colorado. We understand the parking lot will be surfaced with both hot-mix asphalt and a permeable pavement system. The parking lot is expected to be utilized by relatively low volumes of light passenger vehicles. Small cuts and fills are anticipated to develop finish parking lot subgrade elevation. The purpose of our exploration was to describe the subsurface conditions encountered in the completed site borings and develop the test data necessary to provide recommendations concerning development of the parking lot subgrade soils. Pavement section design options are also included along with an estimated infiltration rate for design of permeable pavements. The conclusions and recommendations outlined in this report are based on results of the completed field and laboratory testing and our experience with subsurface conditions in this area. Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 2 SITE DESCRIPTION The proposed parking lot will be constructed northwest of the intersection of West Magnolia Street and North College Avenue, located at 112 West Magnolia Street in Fort Collins, Colorado. At the time of our site exploration, the proposed improvement area was being utilized as a parking lot and did not contain any pavement surfacing. The maximum difference in ground surface elevation across the parking lot area was estimated to be less than one (1) foot. Evidence of prior building construction was not observed in the proposed improvement areas by Soilogic personnel at the time of drilling. EXPLORATION AND TESTING PROCEDURES To develop subsurface information in the proposed improvement area, two (2) soil borings were extended to a depth of approximately 10 feet below present site grade. The boring locations were established in the field by Soilogic personnel based on a provided site plan and by pacing and estimating angles and distances from identifiable site references. The boring locations should be considered accurate only to the degree implied by the methods used to make the field measurements. A diagram indicating the approximate boring locations is included with this report. Graphic logs of each of the auger borings are also included. The test holes were advanced using 4-inch diameter continuous flight auger powered by a truck-mounted CME-45 drill rig. Samples of the subsurface materials were obtained at regular intervals using California barrel sampling procedures in general accordance with ASTM specification D-1586. As part of the D-1586 sampling procedure, the standard sampling barrel is driven into the substrata using a 140-pound hammer falling a distance of 30 inches. The number of blows required to advance the sampler a distance of 12 inches is recorded and helpful in estimating the consistency or relative density of the soils and//or bedrock encountered. In the California barrel sampling procedure, lesser disturbed samples are obtained in removable brass liners. Samples of the subsurface materials obtained in the field were sealed and returned to the laboratory for further evaluation, classification and testing. Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 3 The samples collected were tested in the laboratory to measure natural moisture content and visually and/or manually classified in accordance with the Unified Soil Classification System (USCS). The USCS group symbols are indicated on the attached boring logs. An outline of the USCS classification system is included with this report. As part of the laboratory testing, a calibrated hand penetrometer (CHP) was used to estimate the unconfined compressive strength of essentially cohesive specimens. The CHP also provides a more reliable estimate of soil consistency than tactual observation alone. Dry density, Atterberg limits, -200 wash and swell/consolidation tests were completed on selected samples to help establish specific soil characteristics. Atterberg limits tests are used to determine soil plasticity. The percent passing the #200 size sieve (-200 wash) test is used to determine the percentage of fine-grained soils (clay and silt) in a sample. Swell/consolidation tests are performed to evaluate soil volume change potential with variation in moisture content. The results of the completed laboratory tests are outlined on the attached boring logs and swell/consolidation test summaries. One (1) resistance value (R-value) test was completed on a composite sample of the subgrade soils encountered for use in pavement design. SUBSURFACE CONDITIONS The subsurface materials encountered in the completed site borings can be summarized as follows. Brown/rust lean clay with varying amounts of sand was encountered at the surface at the boring locations. In general the lean clay showed increasing amounts of silty/clayey sand with depth in the completed site borings. The lean clay was medium stiff in terms of consistency, exhibited no to low swell potential at in-situ moisture and density conditions and extended to the bottom of both borings at a depth of approximately 10 feet below grade. Groundwater was not encountered in the completed site borings at the time of drilling and the borings were backfilled prior to leaving the site. Groundwater levels will vary seasonally and over time based on weather conditions, site development, irrigation practices and other hydrologic conditions. Perched and/or trapped groundwater conditions may also be encountered at times throughout the year. Perched water is commonly encountered in soils overlying less permeable soil layers and/or bedrock. Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 4 Trapped water is typically encountered within more permeable zones of layered soil and bedrock systems. The location and amount of perched/trapped water can also vary over time. ANALYSIS AND RECOMMENDATIONS Site Development All remaining topsoil and vegetation (if any) should be completely removed from any proposed fill and within new pavement areas. After stripping and completing all cuts and prior to placement of any fill or pavement materials, we recommend the exposed subgrade soils be scarified to a depth of 9 inches, adjusted in moisture content and compacted to at least 95% of the materials standard Proctor maximum dry density. The moisture content of the scarified subgrade soils should be adjusted to be within the range of ±2% of standard Proctor optimum moisture content at the time of compaction. Scarification and compaction of the exposed subgrade soils in permeable pavement areas should not be completed and care should be taken to avoid densifying the lean clay subgrade soils in these areas. Fill soils required to develop the site should consist of approved low volume change (LVC) soils free from organic matter, debris and other objectionable materials. In order to facilitate construction and maintain performance of permeable pavements, we recommend fill soils required to develop finish parking lot subgrades consist of essentially-granular structural fill or aggregate base course materials. Materials consistent with Colorado Department of Transportation (CDOT) Class 5, 6, or 7 aggregate base course specifications could be considered for use as fill to develop the parking lot area. We recommend essentially granular structural fill soils be placed in loose lifts not to exceed 9 inches thick, adjusted in moisture content and compacted as recommended for the scarified materials above. Care should be taken to avoid disturbing the developed subgrade soils prior to paving. In addition, efforts to maintain the proper moisture content in the subgrade soils should be made. If subgrade soils are disturbed by the construction activities or allowed to dry Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 5 out or become elevated in moisture content, those materials should be reworked in place or removed and replaced prior to paving. Proof-rolling of the parking area subgrade soils outside permeable pavement areas should be completed prior to paving/surfacing to help identify any areas of soft/unstable soils. Those areas identified as unstable would need to be mended prior to paving. Pavement Design Impermeable site pavement materials could be supported directly on stable reconditioned subgrade soils and/or properly placed and compacted fill soils developed as outlined above. Permeable pavements could be supported directly on lean clay subgrade soils and/or properly placed and compacted structural fill also developed as outlined above. A resistance value (R-value) of 5 was determined on a representative sample of the subgrade soils encountered and used in the pavement section design. Traffic loading on the site pavements is expected to consist of relatively low volumes of light vehicles. The equivalent 18-kip single axle load (ESAL) value was estimated for the quantity and type of site traffic anticipated. Pavement section design options are outlined below in Table I. Alternative pavement sections could be considered and we would be happy to discuss any design alternatives at your request. TABLE I - PAVEMENT SECTION DESIGN Standard Duty Option A – Composite Asphaltic Concrete (Grading S or SX) Aggregate Base (Class 5 or 6) 4” 6” Option B - Portland Cement Concrete Pavement PCCP 5” Asphaltic concrete should consist of a bituminous plant mix composed of a mixture of aggregate, filler, binders and additives if required meeting the design requirements of the City of Fort Collins. Aggregate used in the asphaltic concrete should meet specific gradation requirements such as Colorado Department of Transportation (CDOT) grading S (¾-inch minus) or SX (½-inch minus) specifications. Hot mix asphalt designed using Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 6 “Superpave” criteria should be compacted to within 92 to 96% of the materials Maximum Theoretical Density. Aggregate base should be consistent with CDOT requirements for Class 5 or Class 6 aggregate base, placed in loose lifts not to exceed 9 inches thick and compacted to at least 95% of the materials standard Proctor maximum dry density. The proposed pavement section designs do not include an allowance for excessive loading conditions imposed by heavy construction vehicles or equipment. Heavily loaded concrete or other building material trucks and construction equipment can cause some localized distress to the parking area pavements. The recommended pavement sections are minimums and periodic maintenance efforts should be expected. A preventative maintenance program can help increase the service life of the pavements. Permeable Pavements At this time, we understand permeable pavements will be utilized for a portion of the proposed parking area. Permeable pavement subgrades should be developed as outlined in the “Site Development” section of this report. Care should be taken to avoid densification of permeable pavement subgrade soils prior to placement of the overlying system. The near-surface site lean clay is fine graded, such that a filter fabric should be employed at the clay/filter media interface in order to reduce the potential for the migration of fines. Based on visual and tactual evaluation of the lean clay subgrade soils, it is our opinion a percolation rate of 60 minutes per inch or Long-Term Acceptance Rate (LTAR) value of 0.35 gallons/day per square foot could be used in design of permeable site pavements. We recommend permeable pavement filter and storage media be adjusted to a workable moisture content and compacted to at least 75% of the material’s relative density. Drainage Positive drainage is imperative for satisfactory long-term performance of the parking area pavements. Positive drainage should be developed across the parking area pavements and away from the edges of the pavements. Water which is allowed to pond adjacent to site pavements can result in a loss of subgrade support and premature failure of the overlying pavement section. Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 7 GENERAL COMMENTS This report was prepared based upon the data obtained from the completed site exploration, laboratory testing, engineering analysis and any other information discussed. The completed borings provide an indication of subsurface conditions at the boring locations only. Variations in subsurface conditions can occur in relatively short distances away from the borings. This report does not reflect any variations which may occur across the site or away from the borings. If variations in the subsurface conditions anticipated become evident, the geotechnical engineer should be notified immediately so that further evaluation and supplemental recommendations can be provided. The scope of services for this project does not include either specifically or by implication any biological or environmental assessment of the site or identification or prevention of pollutants or hazardous materials or conditions. Other studies should be completed if concerns over the potential of such contamination or pollution exist. The geotechnical engineer should 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. The geotechnical engineer should also be retained to provide testing and observation services during construction to help determine that the design requirements are fulfilled. This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with the generally accepted standard of care for the profession. No warranties express or implied, are made. The conclusions and recommendations contained in this report should not be considered valid in the event that any changes in the nature, design or location of the project as outlined in this report are planned, unless those changes are reviewed and the conclusions of this report modified and verified in writing by the geotechnical engineer. Geotechnical Subsurface Exploration Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic # 16-1181 8 We appreciate the opportunity to be of service to you on this project. If we can be of further service to you in any way or if you have any questions concerning the enclosed information, please do not hesitate to contact us. Very Truly Yours, Soilogic, Inc. Reviewed by: Wolf von Carlowitz, P.E. Darrel DiCarlo, P.E. Principal Engineer Senior Project Engineer 36746 44271 LOG OF BORING B-1 1/1 CME-45 4" CFA Automatic BMc Estimated Swell % Passing SOIL DESCRIPTION Depth "N" MC DD qu % Swell @ Pressure # 200 Sieve (ft) (%) (pcf) (psf) 500 psf (psf) LL PI (%) - 1 CL LEAN CLAY WITH SAND - rust/brown 2 medium stiff - 3 CS 7 14.0 112.2 9000+ 0.2% - 29 13 74.1% - 4 - 5 CS 8 11.8 105.3 9000+ None <500 - - - - 6 Varies to Silty/Clayey Sand with - Depth in Places 7 - 8 - 9 - 10 CS 10 14.2 107.5 9000+ - - - - - BOTTOM OF BORING 10' - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 - LOG OF BORING B-2 1/1 CME-45 4" CFA Automatic BMc Estimated Swell % Passing SOIL DESCRIPTION Depth "N" MC DD qu % Swell @ Pressure # 200 Sieve (ft) (%) (pcf) (psf) 500 psf (psf) LL PI (%) - 1 CL LEAN CLAY WITH SAND - rust/brown 2 medium stiff - 3 CS 9 9.7 98.2 8000 None <500 - - - - 4 - 5 CS 9 7.7 104.7 9000+ 0.3% - - - - - 6 Varies to Silty/Clayey Sand with - Depth in Places 7 - 8 - 9 - 10 CS 8 13.4 93.2 9000+ - - - - - BOTTOM OF BORING 10' - 11 - 12 - 13 - 14 - 15 - 16 - 17 - 18 - 19 - 20 - 21 - 22 - 23 - 24 - 25 - Liquid Limit 39 Plasticity Index 13 % Passing #200 74.1% Dry Density 112.2 pcf WELLS FARGO PARKING LOT 112 WEST MAGNOLIA STREET, FORT COLLINS, COLORADO Project # 16-1181 August 2016 SWELL/CONSOLIDATION TEST SUMMARY Sample ID: B-1 @ 2' Sample Description: Rust/Brown Lean Clay with Sand (CL) Initial Moisture 14.0% Final Moisture 17.0% % Swell @ 500 psf 0.2% Swell Pressure - -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 10 100 1000 10000 100000 --------- Applied Load (psf) Liquid Limit - Plasticity Index - % Passing #200 - Dry Density 105.3 pcf None <500 psf Initial Moisture Final Moisture % Swell @ 500 psf Swell Pressure 11.8% 20.1% Sample Description: Rust/Brown Lean Clay with Sand (CL) Sample ID: B-1 @ 4' WELLS FARGO PARKING LOT 112 WEST MAGNOLIA STREET, FORT COLLINS, COLORADO Project # 16-1181 August 2016 SWELL/CONSOLIDATION TEST SUMMARY -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 10 100 1000 10000 100000 --------- Applied Load (psf) Liquid Limit - Plasticity Index - % Passing #200 - Dry Density 98.2 pcf Final Moisture 23.2% % Swell @ 500 psf None Swell Pressure <500 psf Sample ID: B-2 @ 2' Sample Description: Rust/Brown Lean Clay with Sand (CL) Initial Moisture 9.7% WELLS FARGO PARKING LOT 112 WEST MAGNOLIA STREET, FORT COLLINS, COLORADO Project # 16-1181 August 2016 SWELL/CONSOLIDATION TEST SUMMARY -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 10 100 1000 10000 100000 --------- Applied Load (psf) Liquid Limit - Plasticity Index - % Passing #200 - Dry Density 104.7 pcf Final Moisture 20.6% % Swell @ 500 psf 0.3% Swell Pressure - Sample ID: B-2 @ 4' Sample Description: Rust/Brown Lean Clay with Sand (CL) Initial Moisture 7.7% WELLS FARGO PARKING LOT 112 WEST MAGNOLIA STREET, FORT COLLINS, COLORADO Project # 16-1181 August 2016 SWELL/CONSOLIDATION TEST SUMMARY -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 10 100 1000 10000 100000 --------- Applied Load (psf) UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory TestsA Soil Classification Group Symbol Group NameB Clean Gravels Cu ! 4 and 1 " Cc " 3E GW Well graded gravelF Less than 5% finesC Cu < 4 and/or 1 > Cc > 3E GP Poorly graded gravelF Fines classify as ML or MH GM Silty gravelF,G, H Coarse Grained Soils More than 50% retained on No. 200 sieve Gravels More than 50% of coarse fraction retained on No. 4 sieve Gravels with Fines More than 12% finesC Fines classify as CL or CH GC Clayey gravelF,G,H Clean Sands Cu ! 6 and 1 " Cc " 3E SW Well graded sandI Less than 5% finesD Cu < 6 and/or 1 > Cc > 3E SP Poorly graded sandI Fines classify as ML or MH SM Silty sandG,H,I Sands 50% or more of coarse fraction passes No. 4 sieve Sands with Fines More than 12% finesD Fines classify as CL or CH SC Clayey sandG,H,I Silts and Clays PI > 7 and plots on or above “A” lineJ CL Lean clayK,L,M Liquid limit less than 50 Inorganic PI < 4 or plots below “A” lineJ ML SiltK,L,M Liquid limit - oven dried Organic clayK,L,M,N Fine-Grained Soils 50% or more passes the No. 200 sieve Organic Liquid limit - not dried < 0.75 OL Organic siltK,L,M,O Inorganic PI plots on or above “A” line CH Fat clayK,L,M Silts and Clays Liquid limit 50 or more PI plots below “A” line MH Elastic siltK,L,M Organic Liquid limit - oven dried Organic clayK,L,M,P Liquid limit - not dried < 0.75 OH Organic siltK,L,M,Q Highly organic soils Primarily organic matter, dark in color, and organic odor PT Peat A Based on the material passing the 3-in. (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles or boulders, or both” to group name. C Gravels with 5 to 12% fines require dual symbols: GW-GM well graded gravel with silt, GW-GC well graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay. D Sands with 5 to 12% fines require dual symbols: SW-SM well graded sand with silt, SW-SC well graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay E Cu = D60/D10 Cc = GENERAL NOTES DRILLING & SAMPLING SYMBOLS: SS: Split Spoon - 1⅜" I.D., 2" O.D., unless otherwise noted HS: Hollow Stem Auger ST: Thin-Walled Tube – 2.5" O.D., unless otherwise noted PA: Power Auger RS: Ring Sampler - 2.42" I.D., 3" O.D., unless otherwise noted HA: Hand Auger CS: California Barrel - 1.92" I.D., 2.5" O.D., unless otherwise noted RB: Rock Bit BS: Bulk Sample or Auger Sample WB: Wash Boring or Mud Rotary The number of blows required to advance a standard 2-inch O.D. split-spoon sampler (SS) the last 12 inches of the total 18-inch penetration with a 140-pound hammer falling 30 inches is considered the “Standard Penetration” or “N-value”. For 2.5” O.D. California Barrel samplers (CB) the penetration value is reported as the number of blows required to advance the sampler 12 inches using a 140-pound hammer falling 30 inches, reported as “blows per inch,” and is not considered equivalent to the “Standard Penetration” or “N-value”. 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 Casing Removal Water levels indicated on the boring logs are the levels measured in the borings at the times indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only short-term observations. DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally 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 in-place relative density and fine-grained soils on the basis of their consistency. FINE-GRAINED SOILS COARSE-GRAINED SOILS BEDROCK (CB) Blows/Ft. (SS) Blows/Ft. Consistency (CB) Blows/Ft. (SS) Blows/Ft. Relative Density (CB) Blows/Ft. (SS) Blows/Ft. Consistency < 3 0-2 Very Soft 0-5 < 3 Very Loose < 24 < 20 Weathered 3-5 3-4 Soft 6-14 4-9 Loose 24-35 20-29 Firm 6-10 5-8 Medium Stiff 15-46 10-29 Medium Dense 36-60 30-49 Medium Hard 11-18 9-15 Stiff 47-79 30-50 Dense 61-96 50-79 Hard 19-36 16-30 Very Stiff > 79 > 50 Very Dense > 96 > 79 Very Hard > 36 > 30 Hard RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY Descriptive Terms of Other Constituents Percent of Dry Weight Major Component of Sample Particle Size Trace < 15 Boulders Over 12 in. (300mm) Soilogic, Inc. 3050 67th Avenue, Suite 200  Greeley, CO 80634  (970) 535-6144 P.O. Box 1121  Hayden, CO 81639  (970) 276-2087 April 24, 2017 Quality Engineering, LLC 2637 Midpoint Drive, Suite E Fort Collins, Colorado 80234 Attn: Mr. Cody Geisendorfer, P.E. Re: Addendum #1 to Geotechnical Subsurface Exploration and Pavement Section Design Report Wells Fargo Parking Lot 112 West Magnolia Street, Fort Collins, Colorado Soilogic Project # 16-1181 Mr. Geisendorfer: Our geotechnical subsurface exploration and pavement section design for the referenced project was submitted to your attention in a report dated August 11, 2016. In that report, a minimum 5-inch thick unreinforced Portland cement concrete pavement section design was recommended based in-part on the quantity and type of traffic anticipated to utilize the parking lot as well as subgrade support characteristics. At this time, we understand a 6-inch thick Portland cement concrete pavement supported on two (2) inches of 1-inch minus granular fill overlying eight (8) inches of 1-inch clean rock will be constructed as part of a permeable pavement system. The proposed section as outlined above is structurally greater than the minimum recommended in our pavement design report and in our opinion, would be considered an adequate design alternative from a geotechnical standpoint. We appreciate the opportunity to be of service to you on this project. If we can be of further service to you in any way or if you have any questions concerning the enclosed information, please do not hesitate to contact us. Very Truly Yours, Soilogic, Inc. Reviewed by: Wolf von Carlowitz, P.E. Darrel DiCarlo, P.E. Principal Engineer Senior Project Engineer 36746 44271 With 15 – 29 Cobbles 12 in. to 3 in. (300mm to 75 mm) Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm) Sand Silt or Clay #4 to #200 sieve (4.75mm to 0.075mm) Passing #200 Sieve (0.075mm) RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION Descriptive Terms of Other Constituents Percent of Dry Weight Term Plasticity Index Trace With Modifiers < 5 5 – 12 > 12 Non-plastic Low Medium High 0 1-10 11-30 30+ F If soil contains ! 15% sand, add “with sand” to group name. G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM. HIf fines are organic, add “with organic fines” to group name. I If soil contains ! 15% gravel, add “with gravel” to group name. J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay. K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant. L If soil contains ! 30% plus No. 200 predominantly sand, add “sandy” to group name. M If soil contains ! 30% plus No. 200, predominantly gravel, add “gravelly” to group name. N PI ! 4 and plots on or above “A” line. O PI < 4 or plots below “A” line. P PI plots on or above “A” line. Q PI plots below “A” line. 26 - 27 - 28 - 29 - 30 WELLS FARGO PARKING LOT 112 WEST MAGNOLIA STREET, FORT COLLINS, COLORADO Project # 16-1181 August 2016 Sheet Drilling Rig: Water Depth Information Start Date 7/21/2016 Auger Type: During Drilling None Finish Date 7/21/2016 Hammer Type: After Drilling None Surface Elev. - Field Personnel: 24 Hours After Drilling - USCS Sampler Atterberg Limits 26 - 27 - 28 - 29 - 30 Surface Elev. - Field Personnel: 24 Hours After Drilling - USCS Sampler Atterberg Limits Start Date 7/21/2016 Auger Type: During Drilling None Finish Date 7/21/2016 Hammer Type: After Drilling None WELLS FARGO PARKING LOT 112 WEST MAGNOLIA STREET, FORT COLLINS, COLORADO Project # 16-1181 August 2016 Sheet Drilling Rig: Water Depth Information