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Home My WebLink AboutWINDTRAIL ON SPRING CREEK PUD PHASE TWO PRELIMINARY - 66 93B - SUBMITTAL DOCUMENTS - ROUND 1 - GEOTECHNICAL (SOILS) REPORTTABLE D2 IMF RECOMMENDED PREVENTATIVE MAINTENANCE POLICY FOR JOINTED CONCRETE PAVEMENTS Distress Distress Recommended Distress Distress Recommended Type Severity Maintenance Type Severity Maintenance Low None No Wow -up Polished Severity Groove Surface or Medium Full -Depth Concrete Patch/ Aggregate Levels Overlay High Slab Replacement Defined Low Seal Cracks No Comer Break POp°uts Severity Levels None Medium Full -Depth High Concrete Patch Defined Low Seal Cracks No Underseal, Divided Severity Seal cracks/joints Slab Medium Slab Pumping Levels and Replacement Defined Restore Load Transfer High Low None Low Seal Cracks Medium Full -Depth Patch Medium Full -Depth Durability Punchout Cracking Concrete High Slab Replacement High Patch Low None Low No Faulting Medium Railroad Crossing Medium Policy for this Grind High High Project Low None Sealing Low None Medium Medium Slab Replacement, Joint Map Cracking Seal Reseal Crazing Full -depth Patch, High Joints High or Overlay Low Regrade and No Lane/Shoulder Medium Fill Shoulders Shrinkage Severity None Drop-off to Match Cracks Levels High Lane Height Defined Linear Cracking Low Clean & Low None Longitudinal' Transverse and Seal all Cracks Spelling (Comer) Medium Medium Partial -Depth High Full -Depth Patch High Diagonal Cracks Concrete Patch Low None Low None Large Patching and Spelling Medium Medium Partial -Depth Patch Seal Cracks or (Joint) High High Reconstruct Joint Utility Cuts Replace Patch Low None i Medium Replace Small Patching Patch Empire Laboratories, Inc. High A Division of The Terracon Companies, Inc. 46 All TABLE D1 RECOMMENDED PREVENTATNE MAINTENANCE POLICY FOR ASPHALT CONCRETE PAVEMENTS Distress Distress Recommended Distress Distress Recommended Type Severity Maintenance Type Severity Maintenance Low None Low None Alligator Cracking Patching & VtMh Cut Patching Medium Full -Depth Asphalt Concrete Patch Medium Full -Depth Asphalt Concrete Patch High High Low None Low Bleeding ng Aggregate None Medium Surface Sanding Medium High Shallow AC Patch High Fog Seal Low None Low Shallow AC Patch Medium Clean & Seal Medium Full -Depth Asphalt Concrete Block Cracking Potholes High All Cracks High Patch Bumps & a!� Low None RaiMedium ro g Low No Policy for This Project Shallow AC Patch Medium High Full -Depth Patch High Low None Low None Medium Full -Depth Asphalt Concrete Medium Shallow AC Patch Corrugation Rutting. High Patch High Full -Depth Patch Low None Low None Depression Medium Shallow AC Patch Shoving Medium Mill & Shallow AC High Full -Depth Patch High Patch Low None Low None Edge Cracking Medium Seal Cracks slippage Cracking Medium Shallow Asphalt Concrete High Full -Depth Patch High Patch Low Clean & Low None Joint Reflection Seal All Cracks Swell Medium Medium Shallow AC Patch High Shallow AC Patch High Full -Depth Patch Low None Low Lane/Shoulder Drop -Off Weathering & Ravelling Fog Seal Medium Regrade Medium High Shoulder High Low None Longitudinal & Transverse Cracking Empire Laboratories, Inc. Medium Clean & sea' High All Cracks A Division of The Terracon Companies, Inc. 4i i. REPORT TERMINOLOGY (Based on ASTM D653) Expansive Potential The potential of a soil to expand (increase in volume) due to absorption of moisture. Finished Grade The final grade created as a part of the project. Footing A portion of the foundation of a structure that transmits loads directly to the soil. Foundation The lower part of a structure that transmits the loads to the soil or bedrock. Frost Depth The depth of which the ground becomes frozen during the winter season. Grade Beam A foundation element or wall, typically constructed of reinforced concrete, used to span between other foundation elements such as drilled piers. Groundwater Subsurface water found in the zone of saturation of soils, or within fractures in bedrock. Heave Upward movement. Lithologic The characteristics which describe the composition and texture of soil and rock by observation. Native Grade The naturally occuring ground surface. Native Soil Naturally occurring on -site soil, sometimes referred to as natural soil. Optimum Moisture The water content at which a soil can be compacted to a maximum dry unit Content weight by a given compactive effort. Perched Water Groundwater, usually of limited area maintained above a normal water elevation by the presence of an intervening relatively impervious continuing stratum. Scarify To mechanically loosen soil or break down existing soil structure. Settlement Downward movement. Skin Friction (Side The frictional resistance developed between soil and an element of structure Shear) such as a drilled pier or shaft. Soil (earth) Sediments or other unconsolidated accumulations of solid particles produced by the physical and chemical disintegration of rocks, and which may or may not contain organic matter. Strain The change in length per unit of length in a given direction. Stress The force per unit area acting within a soil mass. Strip To remove from present location. Subbase A layer of specified material in a pavement system between the subgrade and base course. Subgrade The soil prepared and compacted to support a structure, slab or pavement system. Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. REPORT TERMINOLOGY (Based on ASTM D653) Allowable Soil The recommended maximum contact stress developed at the interface of the Bearing Capacity foundation element and the supporting material. Alluvium Soil, the constituents of which have been transported in suspension by flowing water and subsequently deposited by sedimentation. Aggregate Base A layer of specified material placed on a subgrade or subbase usually beneath Course slabs or pavements. Backfill A specified material placed and compacted in a confined area. Bedrock A natural aggregate of mineral grains connected by strong and permanent cohesive forces. Usually requires drilling, wedging, blasting or other methods of extraordinary force for excavation. Bench A horizontal surface in a sloped deposit. Caisson (Drilled pier A concrete foundation element cast in a circular excavation which may have an or Shaft) enlarged base. Sometimes referred to as a cast -in -place pier or drilled shaft. Coefficient of A constant proportionality factor relating normal stress and the corresponding Friction shear stress at which sliding starts between the two surfaces. Co/luvium Soil, the constituents of which have been deposited chiefly by gravity such as at the foot of a slope or cliff. Compaction The densification of a soil by means of mechanical manipulation. Concrete Slab -on- - A concrete surface layer cast directly upon a base, subbase or subgrade, and Grade typically used as a floor system. Differential Unequal settlement or heave between, or within foundation elements of a Movement structure. Earth Pressure The pressure or force exerted by soil on any boundary such as a foundation wall. ESAL Equivalent Single Axle Load, a criteria used to convert traffic to a uniform standard, 0 8,000 pound axle loads). Engineered Fill Specified material placed and compacted to specified density and/or moisture conditions under observations of a representative of a geotechnical engineer. Equivalent Fluid A hypothetical fluid having a unit weight such that it will produce a pressure against a lateral support presumed to be equivalent to that produced by the actual soil. This simplified approach is valid only when deformation conditions are such that the pressure increases linearly with depth and the wall friction is neglected. Existing Fill (or Materials deposited through the action of man prior to exploration of the site. man-made fill) Existing Grade The ground surface at the time of field exploration. Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. Ah LABORATORY TESTS SIGNIFICANCE AND PURPOSE TEST SIGNIFICANCE PURPOSE California Used to evaluate the potential strength of subgrade soil, subbase, Pavement Bearing and base course material, including recycled materials for use in Thickness Ratio road and airfield pavements. Design Used to develop an estimate of both the rate and amount of both Foundation Consolidation differential and total settlement of a structure. Design Used to determine the consolidated drained shear strength of soil Bearing Capacity, Direct or rock. Foundation Design & Shear Slope Stability Dry Used to determine the in -place density of natural, inorganic, fine- Index Property Density grained soils. Soil Behavior Used to measure the expansive potential of fine-grained soil and to Foundation & Slab Expansion provide a basis for swell potential classification. Design Used for the quantitative determination of the distribution of Soil Gradation particle sizes in soil. Classification Liquid & Used as an integral part of engineering classification systems to Soil Plastic Limit, characterize the fine-grained fraction of soils, and to specify the Classification Plasticity Index fine-grained fraction of construction materials. Oxidation- Used to determine the tendency of the soil to donate or accept Corrosion Reduction electrons through a change of the oxidation state within the soil. Potential Potential Used to determine the capacity of soil or rock to conduct a liquid Groundwater Permeability or gas. Flow Analysis Used to determine the degree of acidity or alkalinity of a soil. Corrosion p H Potential Used to indicate the relative ability of a soil medium to carry.. Corrosion Resistivity electrical currents. Potential Used to evaluate the potential strength of subgrade soil, subbase, Pavement R-Value and base course material, including recycled materials for use in Thickness road and airfield pavements. Design Soluble Used to determine the quantitative amount of soluble sulfates Corrosion Sulphate within a soil mass. Potential Used to determine the quantitative amounts of sulfides within a Corrosion Sulfide Content soil mass. Potential To obtain the approximate compressive strength of soils that Bearing Capacity Unconfined possess sufficient cohesion to permit testing in the unconfined Analysis for Compression state. Foundations Water Used to determine the quantitative amount of water in a soil mass. Index Property Content Soil Behavior Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. ROCK CLASSIFICATION (Based on ASTM C-294) Sedimentary Rocks Sedimentary rocks are stratified materials laid down by water or wind. The sediments may be composed of particles of pre-existing rocks derived by mechanical weathering, evaporation or by chemical or organic origin. The sediments are usually indurated by cementation or compaction. Chart Very fine-grained siliceous rock composed of micro -crystalline or crypto- crystalline quartz, chalcedony or opal. Chert is various colored, porous to dense, hard and has a conchoidal to splintery fracture. Claystone Fine-grained rock composed of or derived by erosion of silts and clays or any rock containing clay. Soft massive; gray, black; brown, reddish or green and may contain carbonate minerals. Conglomerate Rock consisting of a considerable amount of rounded gravel, sand and cobbles with or without interstitial or cementing material. The cementing or interstitial material may be quartz, opal, calcite, dolomite, clay, iron oxides or other materials. Dolomite A fine-grained carbonate rock consisting of the mineral dolomite (CaMg (CO3)21' May contain noncarbonate impurities such as quartz, chart, clay minerals, organic matter, gypsum and sulfides. Reacts with hydrochloric acid (HCL). Limestone A fine-grained carbonate rock consisting of the mineral calcite (CaCO3). May contain noncarbonate impurities such as quartz, chart, clay minerals, organic matter, gypsum and sulfides. Reacts with hydrochloric acid (HCL). Sandstone Rock consisting of particles of sand with or.without interstitial and cementing materials. The cementing or interstitial material may be quartz, opal, calcite, dolomite, clay, iron oxides or other material. Shale Fine-grained rock composed of, or derived by erosion of silts and clays or any rock containing clay. Shale is hard, platy, or fissile may be gray, black, reddish or green and may contain some carbonate minerals (calcareous shale). Siltstone Fine grained rock composed of, or derived by erosion of silts or rock containing silt. Siltstones consist predominantly of silt sized particles (0.0625 to 0.002 mm in diameter) and are intermediate rocks between claystones and sandstones, may be gray, black, brown, reddish or green and may contain carbonate minerals. Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. r UNIFIED SOIL CLASSIFICATION SYSTEM Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests" Coarse -Grained Soils more than 50% retained on No. 200 sieve Fine -Grained Soils 50% or more passes the No. 200 sieve Gravels more than 50% of coarse fraction retained on No. 4 sieve Sands 50% or more of coarse fraction passes No. 4 sieve Silts and Clays Liquid limit less than 50 Silts and Clays Liquid limit 50 or more Soil Classification Group Group Names GW Well -graded gravel` GP Poorly graded gravt GM Silty gravel,G,H GC Clayey gravelF,G," SW Well-araded sand' SM Silty sand","' SC Clayey sand"•"•' CL Lean clavE�"•"' OL Organic silt"•"•"'•" CH Fat clay"-"" MH Elastic Silt"•"•"t OH iighly organic soils Primarily organic matter, dark in color, and organic odor PT. Peat Elf soil contains 15 to 29% plus No. 200, add .with sand" or 'with gravel", whichever is predominant. "If soil contains > 30% plus No. 200 predominantly sand, add "sandy" to group name. 'If soil contains > 30% plus No. 200, predominantly gravel, add "gravelly" to group name. "PI > 4 and plots on or above "A" line. ON < 4 or plots below "A" line. 'PI plots on or above "A" line. ePl plots below 'A" line. Clean Gravels Less Cu > 4 and 1 < Cc <3E than 5% finesc Cu < 4 and/or 1 > Cc > 3E Gravels with Fines more than 12% finesc Fines classify as ML or MH Fines classify as CL or CH Clean Sands Less Cu > 6 and 1 < Cc < 3E than 5% fines' Cu < 6 and/or 1 > Cc > 3E Sands with Fines Fines classify as ML or MH more than 12% fines° Fines Classify as CL or CH inorganic PI > 7 and plots on or above "A line' PI < 4 or plots below "A" line' organic Liquid limit - oven dried < 0.75 Liquid limit - not dried inorganic PI plots on or above "A" line PI lots below "A" line organic Liquid limit - oven dried < 0.75 Liquid limit - not dried \Based on the material passing the 3-in. (75-mm) sieve If field sample contained cobbles or rCu'$o�$o Cc ' (DSoI' Dio x $o boulders, or both, add "with cobbles or boulders, or both" to group name. Gravels with 5 to 12% fines require dual `If soil contains > 15% sand, add "with symbols: sand" to group name. GW-GM well -graded gravel with silt elf fines classify as CL-ML, use dual symbol GW-GC well -graded gravel with clay GC -GM, or SC-SM. GP -GM poorly graded gravel with silt "If fines are organic, add "with organic fines" GP -GC poorly graded gravel with clay to group name. 'Sands with 5 to 12% fines require dual 'If soil contains > 15% gravel, add "with symbols: gravel" to group name. SW-SM well -graded sand with silt Jif Atterberg limits plot in shaded area, soil is SW -SC well -graded sand with clay a CL-ML, silty clay. SP-SM poorly graded sand with silt SP-SC poorly graded sand with clay w slit!4LM.o For Woalko"on of Ma-pr"inM WIN ana Gnr rvl.d f.actb" of aoom— p,"Ime �� EyWtiR1 Of A — fM lbriloixal at R - to u - 25.3 ,,,YFFF •J I Vun R � 0.13 (U. 2G) .'" EWvI'cn el V - in �(l WAW at LL 0 ( to 7, Nan R 0.0 (LL - !) �' Goo :' MH OR OH - --:IlCLF)A i ;oO ML ol1 OL 0 0 10 1E 2G )D to w W ro w tw 1W 11C . LIQUID LIMIT (LL) Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. DRILLING AND EXPLORATION DRILLING & SAMPLING SYMBOLS: R : Ring Barrell - 2.42" I.D., 3" O.D., unless otherwise noted SS : Split Spoon - 1%* I.D., 2" O.D., unless otherwise noted PS : Piston Sample ST : Thin -Walled Tube - 2" O.D., unless otherwise noted WS : Wash Sample 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 DC : Dutch Cone WB : Wash Bore Penetration Test: 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 groundwater. In low permeability soils, the accurate determination of groundwater 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-2487 and D-2488. Coarse Grained Soils have more 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 PROPORTIONS OF SAND AND GRAVEL Descriptive Term(s) (of Components Also Percent of Present in Sample) Dry Weight Trace < 15 With 15 - 29 Modifier > 30 RELATIVE PROPORTIONS OF FINES Descriptive Term(s) (of Components Also Percent of Present in Sample) Dry Weight Trace < 5 With 5-12 Modifier > 12 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 GRAIN SIZE TERMINOLOGY Major Component of Sample Size Range Boulders Over 12 in. (300mm) Cobbles 12 in. to 3 in. (300mm to 75mm) Gravel 3 in. to #4 sieve (75mm to 4.75mm) Sand #4 to #200 sieve (4.75mm to 0.075mm) Silt or Clay Passing #200 Sieve (0.075mm) Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. SUMMARY OF TEST RESULTS PROJECT NO. 20935297 won ty % „ , , �.Strength C (PCF) SUMMARY OF TEST RESULTS PROJECT NO. 20935297 Boring No. Depth Ft. Moisture % Dry Density (PCF) Compressive Strength (PCF) Swell Pressure (PCF) Soluble Sulfates % pH Liquid Limit % Plasticity Index % Group Index Classification AASHTO USCS Resistivity (OHM- CM) Penetration Blow/In. 5 0.5-1.5 18.8 3.0-4.0 23.4 99.1 1050 85 4.0-5.0 27.0 5/12 8.0-9.0 20.6 4/12 14.0-15.0 20.7 15/12 6 0.5-1.5 18.6 6/12 3.0-4.0 26.1 104.6 690 4.0-5.0 29.4 4/12 8.0-9.0 31.7 5/12 14.0-15.0 31/12 7 0.5-1.5 18.5 12/12 3.0-4.0 12.2 117.3 6140 310 4.0-5.0 24.9 5/12 9.0-10.0 28.8 6/12 14.0-15.0 23.0 37/1' Comp. Sample 0.5-4.0 32.7 15.5 7.5 CL A-6 (8) 8 0.5-1.5 23.9 16/12 3.0-4.0 20.2 104.7 2320 85 4.0-5.0 15.1 9/12 9.0-10.0 1 18.7 10/12 14.0-15.0 13.8 34/12 9 0.5-1.5 20.9 12/12 SUMMARY OF TEST RESULTS PROJECT NO. 20935297 Boring No. Depth Ft. Moisture % Dry Density (PCF) Compressive Strength (PCF) Swell Pressure (PCF) Soluble Sulfates % pH Liquid Limit % Plasticity Index % Group Index Classification AASHTO USCS Resistivity (OHM- CM) Penetration Blow/In. 1 0.5-1.5 15.3 14/12 3.0-4.0 5.5 102.3 4.0-5.0 27.1 4/12 7.0-8.0 29.2 94.2 8.0-9.0 35.1 3/12 14.0-15.0 20.1 13/12 2 0.5-1.5 30.6 13/12 3.0-4.0 4.0 113.7 7610 235 4.0-5.0 11.2 8/12 8.0-9.0 11.7 8/12 14.0-15.0 16.4 33/12 3 0.5-1.5 16.8 10/12 3.0-4.0 17.3 103.2 1030 85 4.0-5.0 26.2 5/12 7.0-8.0 25.4 96.7 950 8.0-9.0 22.3 4/12 14.0-15.0 12.7 27/12 4 0.5-1.5 9.9 15110 3.0-4.0 11.7 111.8 1680 .0015 4.0-5.0 29.4 5/12 7.0-8.0 22.5 104.0 1570 8.0-9.0 23.8 31/12 14.0-15.0 10.4 29/12 RESISTANCE R-VALUE AND EXPANSION PRESSURE OF COMPACTED SOIL ASTM - D 2844 CLIENT: WINDTRAIL LIMITED LIABILITY COMPANY PROJECT: WINDTRAIL ON SPRING CREEK TRACT B LOCATION OF SAMPLE: COMPOSITE SAMPLE TEST BORING NO. 7 @ 0.5' - 4.0' SAMPLE DATA TEST SPECIMEN 1 2 3 COMPACTION PRESSURE - PSI 0 20 110 DENSITY - PCF 107.0 111.8 114.8 MOISTURE - % 21.4 19.1 16.9 EXPANSION PRESSURE - PSI 0.00 0.00 0.06 HORIZONTAL PRESSURE @ 160 psi 145 140 132 SAMPLE HEIGHT - in. 2.50 2.50 2.50 EXUDATION PRESSURE - PSI 115 306 493 UNCORRECTED R-VALUE 6.8 9.9 14.6 CORRECTED R-VALUE 6.8 9.9 14.6 R-VALUE AT 300 PSI EXUDATION PRESSURE = 9.7 100 '3 0 ......... W6 ......... J CE 7 40 20 0 111 100 200 300 400 500 600 700 EXUDATIGhJ PRESSURE — psi EMPIRE LABORRTORIES INC. Goo 770 6 7 O .6` .63 .61 59 CONSOLIDATION TEST PRO. 20925297 0- BORING NO.:6 DEPTH: 3.0 DRY DENSITY: 94.4 PCF MOISTURE: 28.2 % 0- 0- 0 ol 0.1 0.25 8.0 4 .0 a, 0.0 -16.0 0.5 1.0 5 10 APPLIED PRESSURE - TSF 0.1 0.25 0.5 1.0 5 APPLIED PRESSURE - TSF 10 EMPIRE LABORHTORIES INC. .61 5 cl .57 5: .5' .5 CONSOLIDATION TEST PRO. 2093529P BORING NO. DEPTH: 3.0 DRY DENSITY: 98.!; PCF Mi-ilSTURE: 8.1 % 0 0- 0 4901 0.1 8.0 Ld 4 .0 �Xl 0.0 I Z —4.0 C4 8 .0 7- -16 0 0.25 0.5 1.0 5 10 APPLIED PRESSURE — TSF 0.1 0.25 0.5 1.0 5 APPLIED PRESSURE — TSF EMPIRE LABORATORIES INC, LOG OF BORING NO. 9 Page i of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado Proposed 38 Single - amil Homes SAMPLES TESTS ~ o (D o o J U.>. ca W a DESCRIPTION M z\ � z H� H N W � H WO = S I V) zz XIN-J (L F- N CO W O 3 LA ow W H d ¢ a. U E n. U HO H Yli UMLL F-Z\ W cn > W a J o C3 U z I—cn H H J W Approx. Surface Elev.: 87.2 ft. o :3 z 0� cnm r_ oa =Cn o_ ¢JJ """" 0.5 6" TOPSOIL 86.7 LEAN CLAY WITH SAND Brown, moist, stiff 1 SS 12" 12 2 0.9 32/17/15 CL PA 2.5 84.7 1 ST 12" 123.8 98 1730 2 SS 12" 4 = 5 CL PA CANDY LEAN CLAY WITH GRAVEL Red/tan, moist to wet, medium 3 SS 12" 4 23.8 10 PA 12.0 75.2 SM SILTY SAND WITH GRAVEL Red, wet, medium dense 4 SS 12" 27 19.4 15.0 72.2 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 12-2-93 Empire Laboratories Incorporated Division of Terracon WL 5.0 W.D. = 5.0 A.B. BORING COMPLETED_ 12-2-93 RIG CME-5s FOREMAN DL wL Checked 24 hrs. A.B. APPROVED DAR JOB Il 20935297 LOG OF BORING NO. 8 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado oposed 38 Single - Family Homes SAMPLES TESTS o m ., o 1 LL z } tL W UHi zx W DESCRIPTION >. W Z\ W z HF_ X H = 2 N W � i Cn F O z Z J U) H (L (A L) m r_ W o- O U 3 HO UJ H >-W O W UWLL J U) WWW CD Approx. Surface Elev.: 90.8 ft. o � z z (sm E OIL (na- UU)(La ^^^^^ 0.5 6" TOPSOIL 90.3 LEAN CLAY WITH SAND 1 SS 12" 16 23.9 Brown, moist, stiff to very stiff CL PA 85 1 ST 12" 20.2 105 2320 4.5 86.3 5 2 SS 12" 9 15.1 CL PA SANDY LEAN CLAY WITH GRAVEL Red/tan, moist to wet, medium 9.5 81,3 10 3 SS 12" 10 18.7 SM PA SILTY SAND WITH GRAVEL Red, wet, medium dense to dense �r 4 SS 12" 34 13.8 15.0 75.8 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS Empire Laboratories Incorporated Division of Terracon BORING STARTED 12-2-93 s 4.7 W.D. i4.8 A.B. BORING COMPLETED 12-2-93 IWL RIG CME-ss FOREMAN DL Checked 24 hrs. A.B. APPROVED DAR JOB # 20935297 LOG OF BORING NO. 7 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado Proposed 38 Single - Familv Homes SAMPLES TESTS 0 J U. E to >. <L W N ZS K H DESCRIPTION .. } W.z\ M z HH W a H S S N W � iN H C2 zz MHJ (L F N m W O 3 N ow WHO- ¢ 0- W U to E O (- } U W F- o 0-J H O >- U- XL) U O: LL ZF_Cn F- E \ HHJ CD Approx. Surface Elev.: 93.7 ft. o z f- z om s oo- oma ¢_j_j IA'AA'1 0.5 6" TOPSOIL 93.2 LE N CLAY WITH SAND Brown, moist, stiff 1 SS 12" 12 18.5 33/17/16 CL PA 2.0 91.7 1 ST 12" 12.2 117 6140 SANDY LEAN CLAY 2 SS 12" 5 24.9 WITH GRAVEL Red/tan, moist to wet, medium 5 CL PA t Q 3 SS 12" 6 28.8 10 PA 13.5 80.2 CTT TY SAND WITH GRAVEL SM 4 SS 12" 37 23.0 Red, wet, medium dense to dense 15.0 78.7 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 12-2-93 Empire Laboratories Division of Terracon WL 6.3 W.D. __ g,g A.B. BORING COMPLETED 12-2-93 WL IIncorporated RIG CME-55 FOREMAN DL WL Checked 24 hrs. A.B. APPROVED DAR JOB N 20935297 LOG OF BORING NO. 6 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado Proposed 38 Single - Family Homes SAMPLES TESTS o o 0 o J U- CO M > W W N Z= DESCRIPTION >. 0c z\ X z HF_ H _ ~ vI Q� m W O 3 o W LL CD oW a a W U E W a. U F-o w H YLL Ud'LL W W > } W 0_1 o WU z�_cn LO Approx. Surface Elev.: 88.3 ft. o o z F- X N m I= o o_ o cn a. ^^^ 0.5 6" TOPSOIL 87.8 LEAN CLAY WITH SAND Brown, moist, stiff 1 SS 12" 6 18.6 CL PA 3.0 85.3 1 ST 12" 26.1 105 690 SANDY LEAN CLAY 2 SS 12" 4 29.4 WITH GRAVEL =_ Red/tan, moist to wet, medium 5 CL PA Q 3 SS 12" 5 31.7 PA 10 11.5 76.8 SM SILTY SAND WITH GRAVEL Red, wet, medium dense 4 SS 12" 31 15.0 73.3 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 12-2-93 Empire Laboratories Incorporated WL s 5.8 W.D. IT 4.8 A.B. BORING COMPLETED 12-2-93 WL RIG CME-55 FOREMAN DL Division of Terracon WL Checked 24 hrs. A.B. APPROVED DAR 11OB# 2O935297 LOG OF BORING NO. 5 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado oposed 38 Single - Family Homes SAMPLES TESTS o o 0 ., o ~L I Co >. tL W N zx W HDESCRIPTION } N W O= z\ z z HF- O: = 2 � I N I=- O z z JN Q. cc I.- W (A W m 7 W Y O W 3 W O �U ow ZF(WA Jcn =M((n (L_j CD Approx. Surface Elev.: 89.5 ft. O o z H 0: (nm s Oa o(na cno.a """" 0.5 6" TOPSOIL 89.0 1 SS 12" 9 18.8 10// LEAN CLAY WITH SAND Brown, moist, stiff CL PA 2.5 87.0 85 1 ST 12" 23.4 99 1050 SANDY LEAN CLAY g WITH GRAVEL 2 SS 12" 5 27.0 Red/tan, moist to wet, medium 5 CL PA 3 SS 12" 4 120.6 PA 10 11.5 78.0 SM SILTY SAND WITH GRAVEL Red, wet, medium dense to dense 14.0 75.5 15 WEATHERED CLAYSTONE 15.0 Olive, moist, stiff 74.5 4 SS 12" 15 20.7 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 12-2-93 Empire Laboratories Incorporated WL Q 3.9 W.D. = 3.6 A.B. BORING COMPLETED 12-2-93 WL RIG CME-55 FOREMAN DL Division of Terracon WL Checked 24 hrs. A.B. APPROVED DAR JOB A 20935297 LOG OF BORING NO. 4 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado Proposed 38 Single - Family Homes SAMPLES TESTS f- o o 0 ., o J to M M z H= H DESCRIPTION r u) 0� w zLL o w U-0 x a cc 0- U E 0. U HO H >_U. ow UMLL. w cn o r w ato a- o z(ncn CD Approx. Surface Elev.: 93.1 ft. 0 o z ►- m s oa 00- ocna ^ ^ ^ A A 0.5 6" TOPSOIL 92.6 LEAN CLAY WITH SAND Brown, moist, stiff 1 SS 12" 15 9.9 CL PA 2.0 91.1 1 ST 12" 11.7 112 1680 SANDY LEAN CLAY WITH GRAVEL CL 2 SS 12" 5 29.4 Red/tan, moist to wet, medium 5 PA 3 ST 12" 22.5 104 1570 8.0 85.1 4 SS 12" 31 23.8 SM PA SILTY SAND WITH GRAVEL 10 Red, wet, medium dense 5 SS 12" 29 10.4 15.0 78.1 15 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS Empire Laboratories Incorporated BORING STARTED 12-2-93 45.9 W.D. __ 5.8 A.B. BORING COMPLETED 12-2-93 LWL RIG CME-55 FOREMAN DL Division of Terracon Checked 24 hrs. A.B. APPROVED DAR JOB a 20935297 LOG OF BORING NO. 3 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado Proposed 38 Single - Family Homes SAMPLES TESTS � V ~ o 0 0 .. o J IHy E > U.W N Z 2 W DESCRIPTION N w Z\ M w U_C H = 2 w W i cn H O Z Z J UI O. F— O- (n U c0 E W O. O U 3 ho U) H >_LL. O W UWLL. J U) WWLL. o � z X U) E o 0- a- a- a CD Approx. Surface Elev.: 88.8 ft. 000 Cnn UU)) ^"^" 0.5 6" TOPSOIL 88.3 1 SS 12" 10 16.8 LEAN CLAY WITH SAND Brown, moist, stiff CL PA 2.5 86.3 85 1 ST 12" 17.3 103 1030 SANDY LEAN CLAY WITH GRAVEL 2 SS 12" 5 26.2 Red/tan, moist to wet, medium 5 CL PA Q 3 ST 12" 25.4 97 950 4 SS 12" 4 22.3 SM PA 10 11.5 77.3 MH SILTY CANT) WITH GRAVEL Red, wet, medium dense to dense 14.0 74.8 15 WEATHERED CLAYSTONE/ 15.0 CILTSTONE 73.8 Tan/olive, moist, stiff 5 SS 12" 27 r.7 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 12-2-93 Empire Laboratories Incorporated Division of Tertacon WL s 6.6 W.D. i 5.8 A.B. BORING COMPLETED 12-2-93 WL RIG CME-55 FOREMAN DL WL Checked 24 hrs. A.B. APPROVED DAR JOB # 20935297 LOG OF BORING NO. 2 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado oposed 38 Single - Family Homes SAMPLES TESTS F- o 0 0 ., o J on � z HI— DESCRIPTION } � Z\ M H = 2 N W � i Cn F=- O Zz JN 0- F— (- cn U to E W 0- O U 3 F—O cn H >.U_ O W L)MU- J N WWLL W to > >. W MJ O O:U Zf—(n 3xu) Approx. Surface Elev.: 91.4 ft. o o Z F— O: tom E o 0- o (n a N o_ 0- "^"^" 0.5 6" TOPSOIL 90.9 1 SS 12" 13 30.6 LEAN CLAY WITH_ SAND Brown, moist, stiff CL PA 2.5 88.9 235 1 ST 12" 4.0 114 7610 SANDY LEAN CLAY _ WITH GRAVEL 2 SS 12" 8 11.2 Red/tan, moist to wet, medium 5--PA CL 3 ST NR 4 SS 12" 8 11.7 PA Q 10 11.5 79.9 SM SILTY SAND WITH GRAVEL Red, wet, medium dense to dense 5 SS 12" 33 16.4 15.0 76.4 115 BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS Empire Laboratories Incorporated BORING STARTED 12-2-93 WL s 9.7 W.D. = 6.0 A.B. BORING COMPLETED 12-2-93 WL RIG CME-55 FOREMAN DL Division of Tenacon vVL Checked 24 hrs. A.B. APPROVED DAR JOB # 20935297 LOG OF BORING NO. 1 Page 1 of 1 CLIENT ARCHITECT/ENGINEER Windtrail Limited Liability Co. Jim Sell Design SITE Hill Pond Road & Gilgalad Way PROJECT Fort Collins, Colorado Proposed 38 Single - Family Homes SAMPLES TESTS W s z a > w U W g Z\ I—o (n io \ W � ►N-i E >. U)Z W >-U. o a- S U-0 ow o c~n a J H cc DESCRIPTION Approx. Surface Elev.: 94.9 ft. U_ a wo J E N U � A A A A A 0.5 6" TOPSOIL 94.4 1 SS 12" 14 15.3 LEAN CLAY WITH SAND Brown, moist, stiff to very stiff CL PA 2.5 92.4 1 ST 12" 5.5 102 2 SS 12" 4 27.1 SANDY LEAN CLAY WITH GRAVEL 5 PA Red/tan, moist to wet, medium CL 3 ST 12" 29.2 94 4 SS 12" 3 35.1 PA 10 14.5 80.4 15 SM 5 SS 12" 13 20.1 15.0 SILTY SAND WITH GRAVEL 79.9 Red, wet, medium dense BOTTOM OF BORING THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL AND ROCK TYPES: IN -SITU, THE TRANSITION MAY BE GRADUAL. WATER LEVEL OBSERVATIONS BORING STARTED 12-2-93 Empire Laboratories Incorporated S 5.8 W.D. 5.7 A.B. BORING COMPLETED 12-2-93 1wL „ L RIG C� FOREMAN DL Division of Terrecon YL Checked 24 hrs. A.B. APPROVED DAR JOB H 2O935297 $ I K }} c.4 � 1 �1 bTI�I 1I-_..... IoiJ._ . sPh1 �l �'ai� a��t�-•I�i �' � , n; i G i LzwkLAv ►�JA`( �AT0 Empire Laboratories, Inc. A Division of The Terracon Companies, Inc. Windtrail Limited Liability ELI Project No. 20935297 The analyses and recommendations in this report are based in part upon data obtained from the field exploration. The nature and extent of variations beyond the location of test borings may not become evident until construction. If variations then appear evident, it may be necessary to reevaluate the recommendations of this report. Our professional services were performed using that degree of care and skill ordinarily exercised, under similar circumstances, by reputable geotechnical engineers practicing in this or similar localities. No warranty, express or implied, is made. We prepared the report as an aid in design of the proposed project. This report is not a bidding document. Any contractor reviewing this report must draw his own conclusions regarding site conditions and specific construction techniques to be used on this project. This report is for the exclusive purpose of providing geotechnical engineering and/or testing information and recommendations. The scope of services for this project does not include, either specifically or by implication, any environmental assessment of the site or identification of contaminated or hazardous materials or conditions. If the owner is concerned about the potential for such contamination, other studies should be undertaken. We are available to discuss the scope of such studies with you. 18 r Windtrail Limited Liability ELI Project No. 20935297 Additional Design and Construction Considerations: • Exterior Slab Design and Construction: Exterior slabs -on -grade, exterior architectural features, and utilities founded on, or in backfill may experience some movement due to the volume change of the backfill. Potential movement could be reduced by: • minimizing moisture increases in the backfill • controlling moisture -density during placement of backfill • using designs which allow vertical movement between the exterior features and adjoining structural elements • placing effective control joints on relatively close centers • allowing vertical movements in utility connections • Corrosion Protection: Results of soluble sulfate testing indicate that ASTM Type I Portland cement is suitable for all concrete on and below grade. However, if there is no, or minimal cost differential, use of ASTM Type II Portland cement is recommended for additional sulfate resistance of construction concrete. Foundation concrete should be designed in accordance with the provisions of the ACI Design Manual, Section 318-121. GENERAL COMMENTS It is recommended that the Geotechnical Engineer be retained to provide a general review of final design plans and specifications in order that grading and foundation recommendations may be interpreted and implemented. In the event that any changes of the proposed project are planned, the conclusions and recommendations contained in this report should be reviewed and the report modified or supplemented as necessary. The Geotechnical Engineer should also be retained to provide services during excavation, grading, foundation and construction phases of the work. Observation of footing excavations should be performed prior to placement of reinforcing and concrete to confirm that satisfactory bearing materials are present and is considered a necessary part of continuing geotechnical engineering services for the project. Construction testing of fill placed on the site is considered part of continuing geotechnical engineering service for the project. Field and laboratory testing of concrete and steel should be performed to determine whether applicable requirements have been met. It would be logical for Empire Laboratories, Inc. to provide these services since we are most qualified to 'determine consistency of field conditions with those data used in our analyses. 17 Windtrail Limited Liability ELI Project No. 20935297 Drainage: • Surface Drainage: 1. Positive drainage should be provided during construction and maintained throughout the life of the proposed townhome construction project. Infiltration of water into utility or foundation excavations must be prevented during construction. Planters and other surface features which could retain water in areas adjacent to the building or pavements should be sealed or eliminated. 2. In areas where sidewalks or paving do not immediately adjoin the structure, we recommend that protective slopes be provided with a minimum grade of approximately ten percent for at least 10 feet from perimeter walls. Backfill against footings, exterior walls, and in utility and sprinkler line trenches should be well compacted and free of all construction debris to reduce the possibility of moisture infiltration. 3. Downspouts, roof drains or scuppers should discharge into splash blocks or extensions when the ground surface beneath such features is not protected by exterior slabs or paving. 4. Sprinkler systems should not be installed within five feet of foundation walls. Landscape irrigation adjacent to the foundation system should be minimized or eliminated. 0 Subsurface Drainage: Free -draining, granular soils containing less than five percent fines (by weight) passing a No. 200 sieve should be placed adjacent to walls which retain earth. A drainage system consisting of either weep holes or perforated drain lines (placed near the base of the wall) should be used to intercept and discharge water which would tend to saturate the backfill. Where used, drain lines should be embedded in a uniformly graded filter material and provided with adequate clean -outs for periodic maintenance. An impervious soil should be used in the upper layer of backfill to reduce the potential for water infiltration. 16 Windtrail Limited Liability ELI Project No. 20935297 Compliance: Recommendations for slabs -on -grade, foundations and pavement elements supported on compacted fills or prepared subgrade depend upon compliance with "Earthwork" recommendations. To assess compliance, observation and testing should be performed under the direction of the geotechnical engineer. Utility Construction: Excavations into the on -site soils will encounter a variety of conditions. Excavations into the clays and bedrock can be expected to stand on relatively steep temporary slopes during construction. However, caving soils may also be encountered. 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. 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. The soils to be penetrated by the proposed excavations may vary significantly across the site. The preliminary soil classifications are based solely on the materials encountered in widely spaced exploratory test borings. The contractor should verify that similar conditions exist throughout the proposed area of excavation. If different subsurface conditions are encountered at the time of construction, we recommend that we be contacted immediately to evaluate the conditions encountered. As a safety measure, it is recommended that all vehicles and soil piles be kept to a minimum lateral distance from the crest of the slope equal to no less than the slope height. The exposed slope face should be protected against the elements. It is recommended that the contractor retain a geotechnical engineer to monitor the soils exposed in all excavations and provide engineering services for such slopes. This will provide an opportunity to monitor the soil types encountered and to modify the excavation slopes as necessary. It also offers an opportunity to verify the stability of the excavation slopes during construction. 15 Windtrail Limited Liability ELI Project No. 20935297 • Liquid Limit .................................... 35 (max) • Plasticity Index .................................. 15 (max) • Minimum R-Value................................. 10 (min) 4. Aggregate base should conform to Colorado Department of Transportation Class 5 or 6 specifications. • Placement and Compaction: 1. Place and compact fill in horizontal lifts, using equipment and procedures that will produce recommended moisture contents and densities throughout the lift. 2. Uncompacted fill lifts should not exceed 10 inches loose thickness. 3. No fill should be placed over frozen ground. 4. Materials should be compacted to the following: Material On -site soils: Minimum Percent Compaction (ASTM D698) Beneath foundations ................................... 95 Beneath slabs ........................................ 95 Beneath pavements ................................... 95 Imported fill: Beneath foundations ................................... 95 Beneath slabs ....................................... 95 Beneath pavements ................................... 95 Aggregate base (beneath pavement) ............................. 95 Miscellaneous backfill....................................... 90 5. On -site clay soils should be compacted within a moisture content of optimum moisture to 2 percent above optimum. Imported granular soils should be compacted within a moisture range of 2 percent below to 2 percent above optimum. 14 Windtrail Limited Liability ELI Project No. 20935297 • Pavement Subgrade Preparation: 1. The subgrade should be scarified, moistened as required, and recompacted for a minimum depth of 8 inches prior to placement of fill and pavement materials. 2. Due to the plastic nature of the subsoils, the need for subgrade stabilization is anticipated. On -site clay soils may pump or become unstable or unworkable at high water contents. Workability may be improved by scarifying and drying. Overexcavation of wet zones and replacement with granular materials may be necessary. Use of lime, fly ash, kiln dust, cement or geotextiles could also be considered as a stabilization technique. Adequate laboratory testing should be performed to evaluate the effectiveness of each chosen method of stabilization. Lightweight excavation equipment may be required to reduce subgrade pumping. • Fill Materials: 1. Clean on -site soils or approved imported materials may be used as fill material for the following: • general site grading • exterior slab areas • foundation areas • pavement areas • interior floor slab areas • foundation backfill 2. Frozen soils should not be used as fill or backfill. 3. Imported soils (if required) should be approved by the geotechnical engineer and conform to the following: • Gradation (ASTM C136): percent finer by weight 6.. .............................................. 100 3.. ........................................... 70-100 No. 4 Sieve ..................................... 50-100 No. 200 Sieve .................................. 25 (max) 13 Windtrail Limited Liability ELI Project No. 20935297 2. If unexpected fills or underground facilities are encountered during site clearing, such features should be removed, the excavation thoroughly cleaned prior to backfill placement and construction. All excavations should be observed by the geotechnical engineer prior to backf ill placement. 3. Stripped materials consisting of organic materials should be wasted from the site, or used to revegetate exposed slopes after completion of grading operations. If it is necessary to dispose of organic materials on -site, they should be placed in non- structural areas, and in fill sections not exceeding 5 feet in height. 4. Sloping areas steeper than 2:1 (horizontal:vertical) should be benched to reduce the potential for slippage between existing slopes and fills. Benches should be level and wide enough to accommodate compaction and earth moving equipment. 5. The site should be initially graded to create a relatively level surface to receive fill, and to provide for a relatively uniform thickness of fill beneath proposed building structures and/or pavement areas. • Excavation: 1. It is anticipated that excavations for the proposed construction can be accomplished with conventional earthmoving equipment. 2. Depending upon depth of excavation and seasonal conditions, groundwater may be encountered in excavations on the site. Pumping from sumps may be utilized to control water within excavations. Well points may be required for significant groundwater flow, or where excavations penetrate groundwater to a significant depth. • Slab Subarade Preparation: 1. Where existing on -site clay soils will support floor slab, the soils should be scarified, moisture conditioned and compacted to a minimum depth of 12 inches. 2. A minimum 4-inch layer of clean, graded gravel or crushed rock devoid of fines should be placed beneath slabs. A minimum 8-inch layer of clean, graded gravel and/or crushed rock devoid of fines should be placed beneath floor slabs surrounded by perimeter drains. 12 Windtrail Limited Liability ELI Project No. 20935297 • Placing compacted backfill against the exterior side of curb and gutter; and, • Placing curb, gutter and/or sidewalk directly on subgrade soils without the use of base course materials. Preventative maintenance should be planned and provided for through an on -going pavement management program in order to enhance future pavement performance. Preventative maintenance activities are intended to slow the rate of pavement deterioration, and to preserve the pavement investment. Preventive maintenance consists of both localized maintenance (e.g. crack sealing and patching) and global maintenance (e.g. surface sealing). Preventative maintenance is usually the first priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements. Recommended preventative maintenance policies for asphalt and jointed concrete pavements, based upon type and severity of distress, are provided in Appendix D. Prior to implementing any maintenance, additional engineering observation is recommended to determine the type, and extent of preventative maintenance. Earthwork: • General Considerations: The conclusions contained in this report for the proposed construction are contingent upon compliance with recommendations presented in this section. Although fills, underground facilities, such as septic tanks, cesspools, basements, or utilities, were not observed during site reconnaissance, such features might be encountered during construction. • Site Clearing: 1. Strip and remove existing vegetation,. debris, and other deleterious materials from proposed building and pavement areas. All exposed surfaces should be free of mounds and depressions which could prevent uniform compaction. 11 Windtrail Limited Liability ELI Project No. 20935297 • Maximum Water Content ....................... 0.49 lb/lb of cement • Maximum Allowable Slump ............................... 4 inches Concrete should be deposited by truck mixers or agitators and placed a maximum of 90 minutes from the time the water is added to the mix. Other specifications outlined by the Colorado Department of Transportation should be followed. Longitudinal and transverse joints should be provided as needed in concrete pavements for expansion/contraction and isolation. The location and extent of joints should be based upon the final pavement geometry and should be spaced (in feet), at roughly twice the slab thickness (in inches), on center in either direction. Sawed joints should be cut within 24-hours of concrete placement, and should be a minimum depth of 25% of slab thickness plus 1/4 inch. All joints should be sealed to prevent entry of foreign material and dowelled where necessary for load transfer. Where dowels cannot be used at joints accessible to wheel loads, pavement thickness should be increased by 25 percent at the joints and tapered to regular thickness in 5 feet. Future performance of pavements constructed on the clay soils at this site will be dependent upon several factors, including: • Maintaining stable moisture content of the subgrade soils; and, • Providing for a planned program of preventative maintenance. Since the clay soils on the site have shrink/swell characteristics, pavements could crack in the future primarily because of expansion of the soils when subjected to an increase in moisture content to the subgrade. The cracking, while not desirable, does. not necessarily constitute structural failure of the pavement. The performance of all pavements, but in particular the recommended asphalt sections, can be enhanced by minimizing excess moisture which can reach the subgrade soils. The following recommendations should be considered at minimum: • Site grading at a minimum 2% grade away from the pavements; • Compaction of any utility trenches for landscaped areas to the same criteria as the pavement subgrade; • Sealing all landscaped areas in, or adjacent to pavements to minimize or prevent moisture migration to subgrade soils; 10 Windtrail Limited Liability ELI Project No. 20935297 Each alternative should be investigated with respect to current material availability and economic conditions. In view of the subgrade soil conditions and projected traffic, either full -depth asphalt or rigid concrete pavement sections should be considered in areas of main traffic corridors, drive bays or truck access. Rigid concrete pavement is recommended at the location of dumpsters where trash trucks will park and load. Aggregate base course (if used on the site) should consist of a blend of sand and gravel which meets strict specifications for quality and gradation. Use of materials meeting Colorado Department of Transportation Class 5 or 6 specifications is recommended. In addition, the base course material should be moisture stable. Moisture stability is determined by R-value testing which shows a maximum 12 point difference in R-values between exudation pressures of 300 psi and 100 psi. Aggregate base course material should be tested to determine compliance with these specifications prior to importation to the site. Aggregate base course should be placed in lifts not exceeding six inches and should be compacted to a minimum of 95% Standard Proctor density (ASTM D-698), within a moisture content range of 2 percent below, to 2 percent above optimum. Where base course thickness exceeds 6 inches, the material should be placed and compacted in two or more lifts of equal thickness. Asphalt concrete should be obtained from an approved mix design stating the Hveem properties, optimum asphalt content, job mix formula, and recommended mixing and placing temperatures. Aggregate used in asphalt concrete should meet a particular gradation. Use of materials meeting Colorado Department of Transportation Grading C or CX specifications is recommended. The mix design should be submitted prior to construction to verify its adequacy. The asphalt material should be placed in maximum 3-inch lifts, and should be compacted to a minimum of 95 % Hveem density (ASTM D-1561). Where rigid pavements are used the concrete should be obtained from an approved mix design with the following minimum properties: • Compressive Strength @ 28 days ................... 3750 psi minimum • Modulus of Rupture @ 28 days ..................... 650 psi minimum 0 Strength Requirements ............................... ASTM C-94 4 Minimum Cement Content .......................... 5.5 sacks/cu.yd. • Cement Type .................................... Type I Portland • Entrained Air Content ................................. 6% + 2% • Concrete Aggregate ................ ASTM C-33 and CDOT Section 703 • Aggregate Size ................................. 1 inch maximum E Windtrail Limited Liability ELI Project No. 20935297 Based upon AASHTO criteria, Colorado is located within Climatic Region VI of the United States. This region is characterized as being dry, with hard ground freeze and spring thaw. The spring thaw condition typically results in saturated or near -saturated subgrade soil moisture conditions. The AASHTO criteria suggests that these moisture conditions are prevalent for approximately 12.5% of the annual moisture variation cycle. Local drainage characteristics of proposed pavements areas are considered to vary from fair to good depending upon location on the site. For purposes of this design analysis, fair drainage characteristics are considered to control the design. These characteristics, coupled with the approximate duration of saturated subgrade conditions, results in a design drainage coefficient of 1.0 when applying the AASHTO criteria for design. For flexible pavement design, a terminal serviceability index of 2.0 was utilized along with an inherit reliability of 70% for the local streets. Using the correlated design R-value, appropriate ESAL/day, environmental criteria and other factors, the structural numbers (SN) of the pavement sections were determined on the basis of the 1986 AASHTO design equation. In addition to the flexible pavement design analyses, a rigid pavement design analysis was completed, based upon AASHTO design procedures. Rigid pavement design is based on an evaluation of the Modulus of Subgrade Reaction of the soils (K-Value), the Modulus of Rupture of the concrete, and other factors previously outlined. The design K-value of 100 for the subgrade soil was determined by correlation to the laboratory test results. A Modulus of Rupture of 650 psi (working stress 488 psi) was used for pavement concrete. The rigid pavement thicknesses for each traffic category were determined on the basis of the AASHTO design equation. Recommended alternatives for flexible and rigid pavements, summarized for each traffic area, are as follows: Recommended Pavement Section Thickness (Inches) Traffic Area Alterna- tive Asphalt Aggregate Plant Mix Portland Concrete Base Bituminous Cement TOTAL Surface Course Base Course Concrete A 3" 4" 7" B 2" 2'/2 " 4'/: " Local Streets, Cul-de-Sacs C6" 61' 0 Windtrail Limited Liability ELI Project No. 20935297 within general tolerance for normal slab -on -grade movements. To reduce any potential slab movements, the subgrade soils should be prepared as outlined in the earthwork section of this report. Additional floor slab design and construction recommendations are as follows: • Positive separations and/or isolation joints should' be provided between slabs and all foundations, columns or utility lines to allow independent movement. • Contraction joints should be provided in slabs to control the location and extent of cracking. Maximum joint spacing of 15 to 20 feet in each direction is recommended. • Interior trench backfill placed beneath slabs should be compacted in accordance with recommended specifications outlined below. • In areas subjected to normal loading, a minimum 4-inch layer of clean, graded gravel or crushed rock devoid of fines should be placed beneath interior slabs. For heavy loading, reevaluation of slab and/or gravel thickness may be required. • If moisture sensitive floor coverings are used on interior slabs, consideration should be given to the use of barriers to minimize potential vapor rise through the slab. • Floor slabs should not be constructed on frozen subgrade. • Other design and construction considerations, as outlined in the ACI Design Manual, Section 302.1 R are recommended. Low Volume Residential Pavement Desion and Construction: Design of low volume residential pavements for the project have been based on the procedures outlined in the 1986 Guideline for Design of Pavement Structures by the American Association of State Highway and Transportation Officials (AASHTO). Design of non-residential and/or high volume residential pavements for the project will be provided in an addendum to this report when traffic data becomes available. Traffic criteria used for the pavement thickness designs include Equivalent Single Axle Loads (ESAL's) of 5 for low volume residential streets, such as local streets and cul-de-sacs. h] Windtrail Limited Liability ELI Project No. 20935297 dead -load pressure will also reduce differential settlement between adjacent footings. Total or differential settlements resulting from the assumed structural loads are estimated to be on the order of 3/4-inch or less, provided that foundations are constructed as recommended. 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. Footings, foundation walls and masonry walls should be reinforced as necessary to reduce the potential for distress caused by differential foundation movements. The use of joints at openings or other discontinuities in masonry walls is recommended. Foundation excavations should be observed by the geotechnical engineer. If the soil conditions encountered differ significantly from those presented in this report, supplemental recommendations will be required. Crawl -Space Construction: Groundwater was encountered on the site at relatively shallow depths of three and one-half (3'/2) to six (6) feet below existing site grades. Therefore, full -depth basement construction is not considered feasible on the site without considerable fill material being placed to elevate the site to maintain a minimum distance of three (3) feet between the lower basement slab and the groundwater elevation. However, crawl -space construction is considered feasible on the site with the existing site grades provided that the bottom of the footings are placed a minimum of 2 feet above the groundwater level. To reduce the potential for groundwater to enter the proposed basement and/or crawl -space areas of the residential structures, installation of a dewatering system is recommended. The dewatering system should, at a minimum, include an underslab gravel drainage layer sloped to a perimeter drainage system. The drainage system should consist of a properly sized perforated pipe, embedded in free -draining gravel, placed in a trench at least 12-inches in width. Gravel should extend a minimum of 3- inches beneath the bottom of the pipe. The drainage system should be sloped at a minimum 1 /8 inch per foot to a suitable outlet, such as a sump and pump system. The underslab drainage layer should consist of a minimum 8-inch thickness of free -draining gravel meeting the specifications of ASTM C33, Size No. 57 or 67. Floor Slab Design and Construction: It is anticipated that low to moderately expansive subsoils will support the floor slab. Some differential movement of a slab -on -grade floor system is possible should the subgrade soils become elevated in moisture content. Such movements are considered a Windtrail Limited Liability ELI Project No. 20935297 Laboratory Test Results: Laboratory test results indicate that the on -site clay subsoils at shallow depth have low to moderate expansive potential. The bedrock stratum exhibits a moderate to high expansive potential. When water is added to compacted near -surface soils, the materials exhibit a moderate expansive potential. Groundwater Conditions: Groundwater was encountered at depths of four (4) to ten (10) feet below the surface in the test borings at the time of initial field exploration. When checked 24 hours after drilling, groundwater was measured at depths of three and one-half (3'/:) to six (6) feet below the surface. These observations represent only current groundwater conditions and may not be indicative of other times or at other locations. Groundwater levels can be expected to fluctuate with varying seasonal and weather conditions and irrigation demands on and/or adjacent to the subject property. CONCLUSIONS AND RECOMMENDATIONS Site Development Considerations: The site appears suitable for the proposed construction. Because of variations in the engineering properties of the on -site soils, foundation bearing levels, structural loads, and possible final grades, the following foundation system was evaluated for use on the site: • conventional -type spread footings bearing on undisturbed soils; and, • conventional -type spread footings bearing on engineered fill material. Foundation Systems: Due to the presence of low to moderate expansive soils at the site, conventional -type spread footing foundations bearing upon undisturbed natural subsoils and/or engineered fill is recommended for support of the proposed residential structures. The footings may be designed for a maximum bearing pressure of 1,250 pounds per square foot (psf). In addition, the footings should be sized to maintain a minimum dead load pressure of 350 psf. Exterior footings for proposed residential structures should be placed a minimum of 30 inches below finished grade for frost protection. Interior footings should bear a minimum of 12 inches below finished grade. The bottom of the conventional -type spread footings for the proposed single-family homes should be placed a minimum of 2 feet above the groundwater level. Finished grade is the lowest adjacent grade for perimeter footings and floor level for interior footings. The design bearing capacities apply to dead loads plus design live load conditions. Footings should be proportioned to minimize differential foundation movement. Proportioning on the basis of equal total settlement is recommended; however, proportioning to relative constant 3 Windtrail Limited Liability ELI Project No. 20935297 Mapping completed by the Colorado Geological Survey ('Hart, 1972), indicates the site in an area of "Low swell Potential". Potentially expansive materials mapped in this area include bedrock, weathered bedrock and colluvium (surficial units). Soil Conditions: The soil profile at the site consists of strata of materials arranged in different combinations. In order of increasing depths, they are as follows: • Silty Topsoil: The area tested at the subject property is overlain by a 'Y2-foot layer of silty topsoil. The topsoil has been penetrated by root growth and organic matter and should not be used as a fill and/or backfill material. • Lean Clay with Sand: This brown cohesive lean clay with sand underlies the topsoil in all test borings and extends to depths of one (1) to four (4) feet below the surface to the underlying red sandy lean clay stratum. The lean clay is plastic, contains varying amounts of sand and a trace of fine gravel and exhibits low to moderate bearing characteristics in its moist in situ condition. • Sandy Lean Clay: This cohesive tan, red sandy lean clay underlies the upper clay soil and extends to the underlying silty sand with gravel stratum at depths of eight (8) to fourteen and one-half 04Y2) feet below the surface. The sandy lean clay is plastic, contains varying amounts of fine gravel and exhibits moderate bearing characteristics in its moist to wet in situ condition. • Poor Graded Silty Sand with Gravel: This granular stratum was encountered below the upper clay soils in all test borings and extends beyond the depths explored and/or to the underlying bedrock stratum encountered at a depth of fourteen (14) feet below the surface in test boring Nos. 3 and 5. The granular stratum is poorly graded and is moist to wet, medium dense and exhibits moderate bearing characteristics. • Claystone/Siltstone Bedrock: The bedrock stratum was encountered in two of the test borings at a depth of fourteen (14) feet below the surface and extends beyond the depths explored. The upper two (2) to two and one-half (2Y2) feet of the bedrock stratum is highly weathered; however, the underlying siltstone and claystone bedrock is hard and exhibits high bearing characteristics in its moist in situ condition. 'Hart, Stephen S., 1972, Potentially Swelling So# and Rock In the Front Range Urban Corridor, Colorado, Colorado Geological Survey, Environmental Geology No. 7. 4 L] Windtrail Limited Liability ELI Project No. 20935297 Selected soil and bedrock samples were tested for the following engineering properties: • Water content • Consolidation • Dry density • Plasticity 0 Unconfined compression • Soluble sulphate content • Expansion • R-Value The significance and purpose of each laboratory test is described in Appendix C. Laboratory test results are presented in Appendix B, and were used for the geotechnical engineering analyses, and the development of foundation and earthwork recommendations. All laboratory test were performed in general accordance with applicable ASTM, local or other accepted standards. SITE CONDITIONS The area for the proposed construction is presently a vacant tract of land situate east of the existing Hill Pond and Sundering townhomes and north of the proposed Windtrail Townhomes P.U.D. in southwest Fort Collins. The site is vegetated with native grasses and weeds and numerous Russian olive trees. The site is relatively flat and exhibits poor to fair surface drainage in the north to east directions. The property is bordered to the east and north by Spring Creek bike path with vacant, open land beyond to the east and Spring Creek to the north. West of the subject property are two residences, large cottonwood trees and the existing Hill Pond and Sundering townhomes beyond, south of the site is vacant, open land planned as the Windtrail Townhomes P.U.D. and future single-family development land. Located on the southeast portion of the subject site are stockpiles of fill material. SUBSURFACE CONDITIONS Geology: The proposed area is located within the Colorado Piedmont section of the Great Plains physiographic province. The Colorado Piedmont, formed during Late Tertiary and Early quaternary time (approximately 2,000,000 years ago), is a broad, erosional trench which separates the Southern Rock Mountains from the High Plains. Structurally, the site lies along the western flank of the Denver Basin. During the Late Mesozoic and Early Cenozoic Periods (approximately 70,000,000 years ago), intense tectonic activity occurred, causing the uplifting of the Front Range and the associated downwarping of the Denver Basin to the east. Relatively flat uplands and broad valleys characterize the present-day topography of the Colorado Piedmont in this region. 3 Windtrail Limited Liability ELI Project No. 20935297 SITE EXPLORATION The scope of the services performed for this project included site reconnaissance by an engineering geologist, a subsurface exploration program, laboratory testing and engineering analyses. Field Exploration: A total of nine (9) test borings were drilled at the site on December 2, 1993 to depths of 15 feet below the surface at the locations shown on the Site Plan, Figure 1. Six (6) of the test borings were drilled within the areas of the proposed residential structures, and three (3) of the borings were drilled in the areas of the proposed cul-de-sacs and extension to Gilgalad Way. All borings were advanced with a truck -mounted drilling rig utilizing 4-inch and 6-inch diameter continuous -type, power -flight auger drills. The location of borings were positioned in the field by measurements from the property lines and existing site features. Elevations were taken of the ground surface at each boring location by measurements with an engineer's level and reference to a temporary bench mark (TBM) as shown on the Site Plan having an assumed elevation of 100.0. The accuracy of boring locations and elevations should only be assumed to the level implied by the methods used to determine each. Continuous lithologic logs of each boring were recorded by the engineering geologist during the drilling operations. At selected intervals,samples of the subsurface materials were taken by means of pushing thin -walled Shelby tubes, or by driving split -spoon samplers. Representative bulk samples of subsurface materials were obtained from each of the pavement borings. Penetration resistance measurements were taken with each sampling with the split -spoon by driving the sampler with a 140 pound hammer falling 30 inches. When properly interpreted, the penetration resistance is a useful index to the consistency, relative density or hardness of the materials encountered. Groundwater conditions were evaluated in each boring at the time of the initial site exploration, and four days after drilling. Laboratory Testing: All samples retrieved during the field exploration were returned to the laboratory for evaluation by the project geotechnical engineer, and were classified in accordance with the Unified Soil Classification system described in Appendix C. Samples of bedrock were classified in accordance with the general notes for Bedrock Classification. At that time, the field descriptions were confirmed or modified as necessary, final boring logs prepared, and an applicable laboratory testing program was formulated to determine engineering properties of the subsurface materials. Boring Logs for the project are presented in Appendix A. 2 a GEOTECHNICAL ENGINEERING REPORT WINDTRAIL ON SPRING CREEK PROPOSED 38 SINGLE-FAMILY RESIDENCES FORT COLLINS, COLORADO ELI PROJECT NO. 20935297 DECEMBER 9, 1993 INTRODUCTION This report contains the results of our geotechnical engineering exploration for the proposed single- family residential development to be located east of the Hill Pond and Sundering townhomes and north of proposed Windtrail Townhoines P.U.D. in southwest Fort Collins, Colorado. The site is located in the Northwest 1 /4 of Section 23, Township 7 North, Range 69 West of the 6th Principal Meridian, Larimer County, Colorado. The purpose of these services is to provide information and geotechnical engineering recommendations relative to: • subsurface soil and bedrock conditions • groundwater conditions • foundation design and construction • crawl -space construction • floor slab design and construction • pavement design and construction • earthwork • drainage The conclusions and recommendations contained in this report are based upon the results of field and laboratory testing, engineering analyses, and experience with similar soil and structural conditions. PROPOSED CONSTRUCTION Based on information provided concerning construction of the proposed project, it is our understanding that 38 single-family residences having slab -on -grade and/or crawl -space construction are planned at the project site. Final grading plans were not completed prior to preparation of this report. However, it is anticipated that ground floor levels will be slightly above existing site grades. Other major site development will include the extension of Gilgalad Way and three cul-de-sacs. s Windtrail Limited Liability ELI Project No. 20935297 TABLE OF CONTENTS (Cont'd) Page No. APPENDIX A Site Plan .............................................. Figure No. 1 Logs of Borings .......................................... Al thru A9 APPENDIX B Laboratory Test Data: Consolidation Tests .................................. B1 thru B2 Hveem Stabilometer Curve .............. B3 Summary of Test Results .............................. B4 thru B6 APPENDIX C: GENERAL NOTES Drilling &.Exploration ............................................ C1 Unified Soil Classification ......................................... C2 Bedrock Classification, Sedimentary Bedrock ............................ C3 Laboratory Testing, Significance and Purpose ........................... C4 Report Terminology ............................................. C5 APPENDIX D Recommended Preventative Maintenance -Asphalt Concrete Pavements ......... D1 Recommended Preventative Maintenance -Jointed Concrete Pavements ......... D2 Windtrail Limited Liability ELI Project No. 20935297 TABLE OF CONTENTS Page No. Letter of Transmittal................................................... i INTRODUCTION..................................................... PROPOSED CONSTRUCTION ........................................... SITE EXPLORATION .................................................. 2 Field Exploration ............................................... 2 Laboratory Testing .............................................. 2 SITECONDITIONS ................................................... 3 SUBSURFACE CONDITIONS ............................................ 3 Geology..................................................... 3 Soil Conditions ................................................. 4 Laboratory Test Results ........................................... 5 Groundwater Conditions .......................................... 5 CONCLUSIONS AND RECOMMENDATIONS ............................:.... 5 Site Development Considerations .................................... 5 Foundation Systems ............................................. 5 Crawl -Space Construction ......................................... 6 Floor Slab Design and Construction .................................. 6 Low Volume Residential Pavement Design and Construction ................. 7 Earthwork................................................... 11 General Considerations ..................................... 11 Site Clearing ............................................ 11 Excavation............................................. 12 Slab Subgrade Preparation ................................... 12 Pavement Subgrade Preparation ............................... 13 Fill Materials ............................................. 13 Placement and Compaction ................................ 14 Compliance ............................................. 15 Utility Construction ....................................... 15 Drainage.................................................... 16 Surface Drainage ......................................... 16 Subsurface Drainage ....................................... 16 Additional Design and Construction Considerations ...................... 17 Exterior Slab Design and Construction .......................... 17 Corrosion Protection ....................................... 17 GENERAL COMMENTS ............................................... 17 Windtrail Limited Liability ELI Project No. 20935297 Other design and construction details, based upon geotechnical conditions, are presented in the report, such as crawl -space construction, floor slab design and construction, pavement design and construction, earthwork and drainage. We have appreciated being of service to you in the geotechnical engineering phase of this project, and are prepared to assist you during the construction phases as well. If you have any questions concerning this report or any of our testing, inspection, design and consulting services, please feel free to contact us. Sincerely, EMPIRE LABORATORIES, INC. A Division of The Terracon Companies, Inc. �. /P,�� David A. Richer, P.E. Geotechnical Engineer Reviewed by: Chester C. Smith, P.E. Division Manager DAR/CCS/dmf Copies to: Windtrail Limited Liability Company (3) Ms. Kay Force/Jim Sell Design (1) December 9, 1993 Windtrail Limited Liability 3665 JFK Parkway Fort Collins, Colorado 80525 Attn: Mr. John McCoy Re: Geotechnical Engineering Report, Windtrail on Spring Creek Proposed 38 Single -Family Residences Fort Collins, Colorado ELI Project No. 20935297 Empire Laboratories, Inc. (ELI) has completed a geotechnical engineering exploration for the proposed project to be located east of Hill Pond and Sundering townhomes and north of proposed Windtrail Townhomes P.U.D. in southwest Fort Collins, Colorado. This study was performed in general accordance with our proposal number D2093189 dated December 2, 1993. The results of our engineering study, including the boring location diagram, laboratory test results, test boring records, and the geotechnical recommendations needed to aid in the design and construction of foundations and other earth connected phases of this project are attached. The subsurface exploration indicated conditions which are typical of soils commonly found in the southwest Fort Collins area. The subsurface soils at the site predominantly consisted of a lean clay with sand underlain by a sandy lean clay with poorly graded sand and gravel below. The information obtained by the results of field exploration and laboratory testing completed for this study indicates that the soils at the site have low to moderate expansive potential as well as a low to moderate load bearing capability. Based on the geotechnical engineering analyses, subsurface exploration and laboratory test results, it is recommended the proposed single-family residences be supported on a conventional -type spread footing foundation system. Slab -on -grade may be utilized for the interior floor system provided that care is taken in the placement and compaction of the subgrade soil. e- GEOTECHNICAL ENGINEERING REPORT WINDTRAIL ON SPRING CREEK PROPOSED 38 SINGLE-FAMILY RESIDENCES FORT COLLINS, COLORADO ELI PROJECT NO. 20935297 Prepared for: WINDTRAIL LIMITED LIABILITY COMPANY 3665 JFK PARKWAY FORT COLLINS, COLORADO 80525 ATTN: MR. JOHN MCCOY Empire Laboratories, Inc. A Division of The Terracon Companies, Inc.