Loading...
HomeMy WebLinkAboutFile Documents.1315 Sage Ct.0082-2021-BRES (2) I( Kumar&Associates,Inc.° Geotechnical and Materials Engineers 5020 County Road 154 and Environmental Scientists Glenwood Springs,CO 81601 phone: (970)945-7988 fax:(970)945-8454 email:kaglenwood@kumarusa.com An Employee Owned Company www.kumarusa.com Office Locations: Denver(HQ),Parker,Colorado Springs,Fort Collins,Glenwood Springs,and Summit County,Colorado SUBSOIL STUDY FOR FOUNDATION DESIGN PROPOSED BASEMENT ADDITION LOT 4, BLOCK 2, RED BUTTE SUBDIVISION 1315 SAGE COURT ASPEN, COLORADO PROJECT NO. 21-7-152 APRIL 16, 2021 PREPARED FOR: J. MATT JOHNSON 1501 DRAGON STREET, SUITE 102 DALLAS, TEXAS 75207 matt(&,lang-p artners.com RECEIVED 06/04/2021 ASPEN BUILDING DEPARTMENT TABLE OF CONTENTS PURPOSE AND SCOPE OF STUDY - 1 - PROPOSED CONSTRUCTION - 1 - SITE CONDITIONS - 1 - FIELD EXPLORATION - 1 - SUBSURFACE CONDITIONS - 2 - FOUNDATION BEARING CONDITIONS - 2 - DESIGN RECOMMENDATIONS - 3 - FOUNDATIONS - 3 - FOUNDATION AND RETAINING WALLS - 3 - FLOOR SLABS - 4 - UNDERDRAIN SYSTEM - 5 - DRYWELL - 6 - SURFACE DRAINAGE - 6 - LIMITATIONS - 6 - FIGURE 1 - LOCATION OF EXPLORATORY BORING FIGURE 2 - LOG OF EXPLORATORY BORING FIGURES 3 and 4 - GRADATION TEST RESULTS TABLE 1- SUMMARY OF LABORATORY TEST RESULTS TABLE 2 -PERCOLATION TEST RESULTS RECEIVED C1-6-/-0-442021 Kumar&Associates,Inc.° Project No.21-7-152 ASPEN BUILDING DEPARTMENT PURPOSE AND SCOPE OF STUDY This report presents the results of a subsoil study for a proposed basement addition to an existing residence located on Lot 4, Block 2, Red Butte Subdivision, 1315 Sage Court, Aspen, Colorado. The project site is shown on Figure 1. The purpose of the study was to develop recommendations for the foundation design. The study was conducted in accordance with our proposal for geotechnical engineering services to Zone 4 Architects, dated January 14, 2021. A field exploration program consisting of an exploratory boring was conducted to obtain information on the subsurface conditions. Samples of the subsoils obtained during the field exploration were tested in the laboratory to determine their classification and other engineering characteristics. The results of the field exploration and laboratory testing were analyzed to develop recommendations for foundation types, depths and allowable pressures for the proposed building foundation. This report summarizes the data obtained during this study and presents our conclusions, design recommendations and other geotechnical engineering considerations based on the proposed construction and the subsurface conditions encountered. PROPOSED CONSTRUCTION The proposed basement addition will be below the existing garage shown on Figure 1 and connect to the existing residence lower level. The addition footprint will be somewhat larger than the existing garage area. Ground floors will be slab-on-grade. We assume relatively light foundation loadings, typical of the proposed type of construction. If building loadings, location or grading plans change significantly from those described above, we should be notified to re-evaluate the recommendations contained in this report. SITE CONDITIONS The subject site was developed with a two-story residence and detached garage at the time of our field exploration. The addition site is relatively flat and gently sloping down to the north at a grade of about 5% or less. Vegetation consists of landscaped bushes, trees and lawn. FIELD EXPLORATION The field exploration for the project was conducted on March 16, 2021. One exploratory borin was drilled off the driveway at the location shown on Figure 1 to evaluate the subsurface RECEIVE D conditions. The boring was advanced with 4-inch diameter continuous flight augers powered by 0-,/04/2021 Kumar&Associates,Inc.° Project No.21-7-152 ASPEN BUILDING DEPARTMENT -2 - a truck-mounted CME-45B drill rig. The boring was logged by a representative of Kumar& Associates, Inc. Samples of the subsoils were taken with 1% inch and 2-inch I.D. spoon samplers. The samplers were driven into the subsoils at various depths with blows from a 140 pound hammer falling 30 inches. This test is similar to the standard penetration test described by ASTM Method D-1586. The penetration resistance values are an indication of the relative density or consistency of the subsoils. Depths at which the samples were taken and the penetration resistance values are shown on the Log of Exploratory Boring, Figure 2. The samples were returned to our laboratory for review by the project engineer and testing. SUBSURFACE CONDITIONS A graphic log of the subsurface conditions encountered at the site is shown on Figure 2. The subsoils, below about 21/2 feet of mixed clay, silt and sand fill soils, mainly consist of relatively dense, slightly silty sandy gravel with cobbles to the drilled depth of about 21 feet. A relatively dense sand and silt layer was encountered from about 81/2 to 14 feet deep. Laboratory testing performed on samples obtained from the boring included natural moisture content and density and gradation analyses. The results of gradation analyses performed on small diameter drive samples (minus 11/2-inch fraction) of the coarse granular subsoils are shown on Figures 4 and 5. The laboratory testing is summarized in Table 1. Free water was not encountered in the boring at the time of drilling and the soils were moist. FOUNDATION BEARING CONDITIONS The upper fill soils are variable density and unsuitable for support of the proposed addition. The underlying sandy gravel and sandy silt soils possess moderate bearing capacity and typically low settlement potential. At basement excavation depth, we expect the subgrade to consist of the sandy gravel subsoils suitable for support of spread footings. We should observe the building excavation for bearing conditions and the need to sub-excavate fill and silt soils. The City of Aspen requires an engineered excavation stabilization plan if proposed foundations are within 15 feet of a neighboring structure or public travel way. The plan is not required if excavations are less than 5 feet below existing grades or further than 15 feet from travel ways and less than 15 feet deep. Slope bracing through use of a variety of systems such as soil nails or micro-piles should be feasible at the site. A shoring contractor should provide design drag E IVE D to support the proposed excavation slopes. Other City requirements may also be applicable. 0-6 0-4/2 021 Kumar&Associates,Inc.® Project No.21-7-152 ASPEN BUILDING DEPARTMENT - 3 - DESIGN RECOMMENDATIONS FOUNDATIONS Considering the subsurface conditions encountered in the exploratory boring and the nature of the proposed construction, we recommend the building addition be founded with spread footings bearing on the natural granular or silt soils. The design and construction criteria presented below should be observed for a spread footing foundation system. 1) Footings placed on the undisturbed natural granular or silt soils should be designed for an allowable bearing pressure of 2,500 psf. Based on experience, we expect settlement of footings designed and constructed as discussed in this section will be about 1 inch or less. 2) The footings should have a minimum width of 16 inches for continuous walls and 2 feet for isolated pads. 3) Exterior footings and footings beneath unheated areas should be provided with adequate soil cover above their bearing elevation for frost protection. Placement of foundations at least 42 inches below exterior grade is typically used in this area. 4) Continuous foundation walls should be reinforced top and bottom to span local anomalies such as by assuming an unsupported length of at least 12 feet. Foundation walls acting as retaining structures should also be designed to resist lateral earth pressures as discussed in the "Foundation and Retaining Walls" section of this report. 5) The existing fill and any loose or disturbed soils should be removed and the footing bearing level extended down to the relatively dense natural granular or silt soils. The exposed soils in footing area should then be moistened and compacted. 6) A representative of the geotechnical engineer should observe all footing excavations prior to concrete placement to evaluate bearing conditions. FOUNDATION AND RETAINING WALLS Foundation walls and retaining structures which are laterally supported and can be expected to undergo only a slight amount of deflection should be designed for a lateral earth pressure computed on the basis of an equivalent fluid unit weight of at least 50 pcf for backfill cor Er E IV E D of the on-site granular soils. Walls taller than 12 feet should be designed to resist a uniform 0-,/04/2021 Kumar&Associates,Inc.° Project No.21-7-152 ASPEN BUILDING DEPARTMENT -4 - horizontal earth pressure of 25H in psf for wall height H in feet. Cantilevered retaining structures which are separate from the addition and can be expected to deflect sufficiently to mobilize the full active earth pressure condition should be designed for a lateral earth pressure computed on the basis of an equivalent fluid unit weight of at least 40 pcf for backfill consisting of the on-site granular soils. Backfill should not contain organics, debris or rock larger than about 6 inches. All foundation and retaining structures should be designed for appropriate hydrostatic and surcharge pressures such as adjacent footings, traffic, construction materials and equipment. The pressures recommended above assume drained conditions behind the walls and a horizontal backfill surface. The buildup of water behind a wall or an upward sloping backfill surface will increase the lateral pressure imposed on a foundation wall or retaining structure. An underdrain should be provided to prevent hydrostatic pressure buildup behind walls. Backfill should be placed in uniform lifts and compacted to at least 90% of the maximum standard Proctor density at a moisture content near optimum. Backfill placed in pavement and walkway areas should be compacted to at least 95% of the maximum standard Proctor density. Care should be taken not to overcompact the backfill or use large equipment near the wall, since this could cause excessive lateral pressure on the wall. Some settlement of deep foundation wall backfill should be expected, even if the material is placed correctly, and could result in distress to facilities constructed on the backfill. The lateral resistance of foundation or retaining wall footings will be a combination of the sliding resistance of the footing on the foundation materials and passive earth pressure against the side of the footing. Resistance to sliding at the bottoms of the footings can be calculated based on a coefficient of friction of 0.40. Passive pressure of compacted backfill against the sides of the footings can be calculated using an equivalent fluid unit weight of 400 pcf. The coefficient of friction and passive pressure values recommended above assume ultimate soil strength. Suitable factors of safety should be included in the design to limit the strain which will occur at the ultimate strength, particularly in the case of passive resistance. Fill placed against the sides of the footings to resist lateral loads should be a granular material compacted to at least 95% of the maximum standard Proctor density at a moisture content near optimum. FLOOR SLABS The natural on-site soils, exclusive of topsoil and fill, are suitable to support lightly loades __ �/E IVE D on-grade construction. To reduce the effects of some differential movement, floor slabs s oou d 0-,/04/2021 Kumar&Associates,Inc.° Project No.21-7-152 ASPEN BUILDING DEPARTMENT - 5 - be separated from all bearing walls and columns with expansion joints which allow unrestrained vertical movement. Floor slab control joints should be used to reduce damage due to shrinkage cracking. The requirements for joint spacing and slab reinforcement should be established by the designer based on experience and the intended slab use. A minimum 4-inch layer of free- draining gravel should be placed beneath basement level slabs to facilitate drainage. This material should consist of minus 2-inch aggregate with at least 50%retained on the No. 4 sieve and less than 2%passing the No. 200 sieve. All fill materials for support of floor slabs should be compacted to at least 95% of maximum standard Proctor density at a moisture content near optimum. Required fill can consist of the on- site granular soils devoid of vegetation, topsoil and oversized rock. We recommend vapor retarders conform to at least the minimum requirements of ASTM E1745 Class C material. Certain floor types are more sensitive to water vapor transmission than others. For floor slabs bearing on angular gravel or where flooring system sensitive to water vapor transmission are utilized, we recommend a vapor barrier be utilized conforming to the minimum requirements of ASTM E1745 Class A material. The vapor retarder should be installed in accordance with the manufacturers' recommendations and ASTM E1643. UNDERDRAIN SYSTEM Although free water was not encountered during our exploration, it has been our experience in the area that local perched groundwater can develop during times of heavy precipitation or seasonal runoff. Frozen ground during spring runoff can create a perched condition. We recommend below-grade construction, such as retaining walls, crawlspace and basement areas, be protected from wetting and hydrostatic pressure buildup by an underdrain system. The drains should consist of drainpipe placed in the bottom of the wall backfill surrounded above the invert level with free-draining granular material. The drain should be placed at each level of excavation and at least 1 foot below lowest adjacent finish grade and sloped at a minimum 1%to a suitable gravity outlet, drywell or sump and pump. Free-draining granular material used in the underdrain system should contain less than 2%passing the No. 200 sieve, less than 50%passing the No. 4 sieve and have a maximum size of 2 inches. The drain gravel backfill should be at least 1%2 feet deep. RECEIVED 0-6-/0-4/2 0 21 Kumar&Associates,Inc.° Project No.21-7-152 ASPEN BUILDING DEPARTMENT - 6 - DRYWELL Drywells and bio-swales are often used in the Aspen area for site water runoff detention and disposal. The natural granular soils encountered below the fill and clay soils are typically relatively free draining and should be suitable for surface water treatment and disposal. The results of percolation testing performed in Boring 1,presented in Table 2, indicate an infiltration rate of about 2 minutes per inch (rate of 30 inches per hour, equivalent inverted units). The groundwater and bedrock depths are generally known to be relatively deep in this area and should not affect the drywell design. If a drywell is used, it should have solid casing down to at least basement floor level with perforations below that level and located at least 10 feet from the building foundation. SURFACE DRAINAGE The following drainage precautions should be observed during construction and maintained at all times after the addition has been completed: 1) Inundation of the foundation excavations and underslab areas should be avoided during construction. 2) Exterior backfill should be adjusted to near optimum moisture and compacted to at least 95% of the maximum standard Proctor density in pavement and slab areas and to at least 90% of the maximum standard Proctor density in landscape areas. 3) The ground surface surrounding the exterior of the building should be sloped to drain away from the foundation in all directions. We recommend a minimum slope of 6 inches in the first 10 feet in unpaved areas and a minimum slope of 2'/2 inches in the first 10 feet in paved areas. Free-draining wall backfill should be covered with filter fabric and capped with at least 2 feet of the on-site finer graded soils to reduce surface water infiltration. 4) Roof downspouts and drains should discharge well beyond the limits of all backfill. 5) Landscaping which requires regular heavy irrigation should be located at least 5 feet from foundation walls. LIMITATIONS This study has been conducted in accordance with generally accepted geotechnical engineering principles and practices in this area at this time. We make no warranty either express or REerIIECEIVED The conclusions and recommendations submitted in this report are based upon the data obtained 0-,/0-4/2021 Kumar&Associates,Inc.° Project No.21-7-152 ASPEN BUILDING DEPARTMENT - 7 - from the exploratory boring drilled at the location indicated on Figure 1, the proposed type of construction and our experience in the area. Our services do not include determining the presence, prevention or possibility of mold or other biological contaminants (MOBC) developing in the future. If the client is concerned about MOBC, then a professional in this special field of practice should be consulted. Our findings include interpolation and extrapolation of the subsurface conditions identified at the exploratory boring and variations in the subsurface conditions may not become evident until excavation is performed. If conditions encountered during construction appear different from those described in this report, we should be notified so that re-evaluation of the recommendations may be made. This report has been prepared for the exclusive use by our client for design purposes. We are not responsible for technical interpretations by others of our information. As the project evolves, we should provide continued consultation and field services during construction to review and monitor the implementation of our recommendations, and to verify that the recommendations have been appropriately interpreted. Significant design changes may require additional analysis or modifications to the recommendations presented herein. We recommend on-site observation of excavations and foundation bearing strata and testing of structural fill by a representative of the geotechnical engineer. Respectfully Submitted, Kumar& Associates, ;,:,...‘.,, Qp,OO REG ,''4k. . f o * p.A.,, ,i • v) 1 222 - 1 Steven L. Pawla 4 ', z` • s 4, ..... /9/2•..,��iS Reviewed by: i'�� •'•'•••••'• zo 1, ss\�NALEN__ F„...... ...A\14,ji........... Daniel E. Hardin, P.E. SLP/kac cc: Zone 4 Architecture—Tim Andrulaitis tim@zone4architects.com) RECEIVED 06/04/2021 Kumar&Associates,Inc. Project No.21-7-152 ASPEN BUILDING DEPARTMENT / 6._<:/ _.____ XSICH\\ \ / \II. /01 --,, . ,‘\ \ \ -‘ / 099 V \ �ti e. 9 N j t' N 1,I O,$/ @\ 12 R \ l \ '9iL- \ 0 zo% , D.1( 7 _ NN 'YI /1'R �,o11'R 1/ / .. -- N 0'F ,,B", M1 1315 SAC£ • • \ � 4 N. MIX17 FRAMED \ ® ?Q% • \ r /i6 HOUSE - 1 F ° FOUND N0.4 REBAR / B% , }t Ti f' 9 R ll/ \ \ Ban,ASPHALT 5J.3' 11% s s l0 R: ...., \A ,., • %BI 0% w&' Osv.Fl13SJl' SyT F. 11 R: 10'R 7•R 6 R rr \ 9, a.�7731.DD 1� \ 1D'R .1,6 -1 9 B'' \ FOUND NO, \ hu a �7130.f8' N 5 b J I °I ,I REBAF 9 CA MARKED LS 570'IB'SJ E v, „0 a11. 5"O rr l.fJ' N Z. o JOI R 081/1 B• T.°' K' CON ' % LOT 10 BLOCK 2 T,% DRr�E PA I/OO RED BUTTE SU@OMB/ON \ 4B, D F j F 'I \ / CMtm1 <.' A 14'R a1' o BORING 1 1 v 2% �, ;-�� 7/ T / \ 1, /I .; GRADE 6 \ / Tap EL _-------.---\ I Mu Q 7731. ,,,...... -_ D \ 4 — FOUND N04 REBAR )23../Iii.„....., 'R • BELOW ASPHALT \ Q v ja' • 51828701V D 4.91' \ 2B.B' LOT 4, BLOCK 2 'T o,� ,' RED BUTTE SUBDIVISION �h LOT 9,BLOCK 2 -. 0,ly, 1\• RED BUTTE SUBDIVISION -1 f] \ - O•F DITCH BOOK 2A PAGE 288 o� C1 treene 20• r, 42,4J2 Sq Ff ry / >.*p \� 0 15R 0.97 Ac. / 5'I 1 y1,0- _' — — RIM Q�7754.81' i y ry 61 775 \ Centerline 1.0' �' V N , aeB,7 r` / �- LOT BLOCK 2 9 r B I RED BUTTE SUBD/OS/ON /\ r Ili NJ ,o I\ ...ilk N ik , D \ /'N . " N' ...______r QF - LOT 7,BLOCK 2 City'? 'Aspen* '4s_ \ RED BUTTE SUBDIVISION LOT B,BLOCK 2 1:: 2•� i} \ I RED BUTTE SUBDIVISIONto � j\ I �9� o \ 4.ro GPS I y 9 Irj, �4n \\ Elsu�784A � � \GPS \ \\ I Ehv.�JBA.91' \ \ a gi -11 c. I 25 0 25 50 ao APPROXIMATE SCALE FEET 0 6/94/2921 21 -7-152 Kumar & Associates LOCATION OF EXPLORATORY BORING lg. 1 AGFLP,, BUILDING DEPARTMENT BORING 1 LEGEND EL. 7753' TOPSOIL; ORGANIC SILTY CLAYEY SAND, SCATTERED GRAVEL, 0 FIRM, DARK BROWN. 22/12 X FILL: SILTY CLAYEY SAND WITH GRAVEL, MEDIUM DENSE, MOIST, DARK BROWN. 40/6; 50/3 WC=5.6 i _o GRAVEL (GM-GP); SLIGHTLY SILTY, SANDY, COBBLES, DENSE, 5 MOIST, BROWN, ROUNDED ROCK. ��� +4=64 -200=8 /SAND AND SILT (SM-ML); MEDIUM DENSE, MOIST, BROWN. 30/12 / � o - '_ / 17/12 DRIVE SAMPLE, 2-INCH I.D. CALIFORNIA LINER SAMPLE. = 10 WC=8.5 o_ +4=0 o— -200=73 DRIVE SAMPLE, 1 3/8-INCH I.D. SPLIT SPOON STANDARD j PENETRATION TEST. — �� 32/12 22/12 DRIVE SAMPLE BLOW COUNT. INDICATES THAT 22 BLOWS OF 15 WC=2.0 A 140-POUND HAMMER FALLING 30 INCHES WERE REQUIRED DD=115 TO DRIVE THE SAMPLER 12 INCHES. +4=44 -200=4 NOTES 20 � 1. THE EXPLORATORY BORING WAS DRILLED ON MARCH 16, 2021 V■f 41/12 WITH A 4-INCH DIAMETER CONTINUOUS FLIGHT POWER AUGER. 2. THE LOCATION OF THE EXPLORATORY BORING WAS MEASURED APPROXIMATELY BY PACING FROM FEATURES SHOWN ON THE SITE PLAN PROVIDED. 20 3. THE ELEVATION OF THE EXPLORATORY BORING WAS OBTAINED BY INTERPOLATION BETWEEN CONTOURS ON THE SITE PLAN PROVIDED. 4. THE EXPLORATORY BORING LOCATION AND ELEVATION SHOULD BE CONSIDERED ACCURATE ONLY TO THE DEGREE IMPLIED BY THE METHOD USED. 5. THE LINES BETWEEN MATERIALS SHOWN ON THE EXPLORATORY BORING LOG REPRESENT THE APPROXIMATE BOUNDARIES BETWEEN MATERIAL TYPES AND THE TRANSITIONS MAY BE GRADUAL. 6. GROUNDWATER WAS NOT ENCOUNTERED IN THE BORING AT THE TIME OF DRILLING. 7. LABORATORY TEST RESULTS: WC = WATER CONTENT (%) (ASTM D 2216); DD = DRY DENSITY (pcf) (ASTM D 2216); +4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTM D 6913); -200 = PERCENTAGE PASSING NO. 200 SIEVE (ASTM D 1140). ka.f $r 21 -7-152 Kumar &Associates LOG OF EXPLORATORY BORING 0 6%'6 ?2021 ASPEN BUILDING DEPARTMENT HYDROMETER ANALYSIS SIEVE ANALYSIS TIME READINGS U.S. STANDARD SERIES CLEAR SQUARE OPENINGS 24 HRS 7 HRS 100 45 MIN 15 MIN 6OMIN 19MIN 4MIN 1MIN #200 #100 #50#40#30 16 #10#8 #4 3/8" 3/4" 1 1 2" 3" 5"6" 8"0 90 10 80 20 70 - 30 60 40 G ▪ 50 50 II Z1 a• 40 60 E 30 70 20 80 10 90 O I I 1 1 1 1 I I I I I I III I I I I III I I I I I III I I I I I I III 100 .001 .002 .005 .009 .019 .037 .075 .150 .300 .600 1.18 2.36 4.75 9.5 19 38.1 76.2 127 200 .425 2.0 152 DIAMETER OF PARTICLES IN MILLIMETERS CLAY TO SILT SAND GRAVEL COBBLES FINE MEDIUM COARSE FINE COARSE GRAVEL 64 % SAND 28 % SILT AND CLAY 8 % LIQUID LIMIT — PLASTICITY INDEX — SAMPLE OF: Slightly Silty Sandy Gravel FROM: Boring 1 0 4' and 7' (Combined) HYDROMETER ANALYSIS SIEVE ANALYSIS TIME READINGS U.S. STANDARD SERIES CLEAR SQUARE OPENINGS 24 HRS 7 HRS 100 45 MIN 15 MIN 60MIN 19MIN 4MIN 1MIN #200 #100 #50#40#3.1......1.6 #10#8 #4 3/8" 3/4" 1 1/2" 3" 5I 6" 8"0 90 10 [ I 80 20 70 30 60 1 40 IQ — 50 1 50 40 I 60 30 70 20 - 80 I 10 — 90 O I I I I I I I I I I I I I I I I I I I 11 1 1 1 1 100 s' .001 .002 .005 .009 .019 .037 .075 .150 .300 .600 1.18 2.36 4.75 9.5 19 38.1 76.2 127 200 .425 2.0 152 DIAMETER OF PARTICLES IN MILLIMETERS CLAY TO SILT SAND GRAVEL COBBLES FINE MEDIUM COARSE FINE COARSE cTi GRAVEL 0 % SAND 27 % SILT AND CLAY 73 % li LIQUID LIMIT — PLASTICITY INDEX — These test results apply only to the osamples which were tested. The E SAMPLE OF: Sandy Silt FROM: Boring 1 0 10' testing report shall not be reproduced, 2 except in full, without the written ao approval of Kumar & Associates, Inc. mE Sieve analysis testlQQgQgg�qQQ.��is performed in o accordance with A D6913, ASTM D7928, 1 g ASTM C136 and/or TM D1140. p: 21 —7-152 Kumar & Associates GRADATION TEST RESULTS 06%16142021 ASPEN BUILDING DEPARTMENT HYDROMETER ANALYSIS SIEVE ANALYSIS TIME READINGS U.S. STANDARD SERIES CLEAR SQUARE OPENINGS 24 HRS 7 HRS 100 45 MIN 15 MIN 6ONIN 19MIN 4MIN 1MIN #200 #100 '50#40#30 16 #10#8 #4 3/8" 3 4" 1 1 2" 3" 5"6" 8"0 90 10 80 20 70 30 60 40 50 50 u 40 60 30 — 70 20 80 10 90 0 I I III I I I 1 111111 I I 1111 I 111111 I I 1 111111 1 too .001 .002 .005 .009 .019 .037 .075 .150 .300 .600 1.18 12.36 4.75 9.5 19 38.1 76.2 127 200 .425 2.0 152 DIAMETER OF PARTICLES IN MILLIMETERS CLAY TO SILT SAND GRAVEL COBBLES FINE MEDIUM COARSE FINE COARSE GRAVEL 44 % SAND 52 % SILT AND CLAY 4 % LIQUID LIMIT — PLASTICITY INDEX — SAMPLE OF: Slightly Silty Sand and Gravel FROM: Boring 1 0 15' s' -1 These test results apply only to the samples which were tested. The testing report shall not be reproduced, except in full, without the written approval of Kumar & Associates, Inc. o1 g Sieve dCan3c wit h A r _ASTM C136 and/or 0, 21 —7-152 Kumar & Associates GRADATION TEST RESULTS 0 6%64 f 2021 ASPEN BUILDING DEPARTMENT Ic+AKumar&Associates,Inc.° Geotechnical and Materials Engineers and Environmental Scientists TABLE 1 SUMMARY OF LABORATORY TEST RESULTS Project No.21-7-152 SAMPLE LOCATION NATURAL NATURAL GRADATION ATTERBERG LIMITS UNCONFINED MOISTURE DRY GRAVEL SAND PERCENT PLASTIC COMPRESSIVE BORING DEPTH CONTENT DENSITY (%) (%) PASSING 200 S EVE LIQUID LIMIT INDEX STRENGTH SOIL TYPE (ft) (%) (pcf) (%) (%) (psf) 4 and 7 1 5.6 64 28 8 Slightly Silty Sandy Gravel combined 10 8.5 0 27 73 Sandy Silt 15 2.0 115 44 52 4 Slightly Silty Sand and Gravel RECEIVED 06/04/2021 ASPEN BUILDING DEPARTMENT I(+AKumar&Associates,Inc.° Geotechnical and Materials Engineers and Environmental Scientists TABLE 2 PERCOLATION TEST RESULTS PROJECT NO.21-7-152 HOLE NO. HOLE DEPTH LENGTH OF WATER DEPTH WATER DEPTH DROP IN AVERAGE (INCHES) INTERVAL AT START OF AT END OF WATER LEVEL PERCOLATION (MIN) INTERVAL INTERVAL (INCHES) RATE (INCHES) (INCHES) (MIN./INCH) 1 192 3 99 97 2 1.5 97 95 2 1.5 95 93 2 1.5 93 91 2 1.5 91 89 2 1.5 89 87 2 1.5 87 85 2 1.5 85 831/2 1'/2 2 Note: The percolation test was conducted in the completed 4-inch diameter borehole on March 16, 2021. RECEIVED 06/04/2021 ASPEN BUILDING DEPARTMENT