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Home My WebLink AboutFile Documents.1300 Riverside Dr.0309.2017 (37).ARBK 5020 County Road 154 Glenwood ti ood Springs,CO 81601 Geotechnical Engineering I Engineering Geology Phone:(970)945-7988 Materials Testing I Environmental Fax:(970)945-8454 Email: hpkglenwood@kumarusa.com Office Locations: Parker,Glenwood Springs,and Silverthorne,Colorado SUBSOIL STUDY FOR FOUNDATION DESIGN PROPOSED RESIDENCE LOT 6,BLOCK 1,RIVERSIDE SUBDIVISION 1300 RIVERSIDE DRIVE ASPEN, COLORADO PROJECT NO. 17-7-501 JULY 17,2017 PREPARED FOR: S2 ARCHITECTS ATTN: JOSEPH SPEARS 215 SOUTH MONARCH SUITE G-102 ASPEN, COLORADO 81611 (Joseph@ s2architects.com) RECEIVED 12/11/2017 ASPEN BUILDING DEPARTMENT TABLE OF CONTENTS PURPOSE AND SCOPE OF STUDY - I - PROPOSED CONSTRUCTION - 1 - SITE CONDITIONS - 2 - FIELD EXPLORATION - 2 - SUBSURFACE CONDITIONS - 2 - FOUNDATION BEARING CONDITIONS - 3 - DESIGN RECOMMENDATIONS - 3 - FOUNDATIONS - 3 - FOUNDATION AND RETAINING WALLS -4 - FLOOR SLABS - 5 - UNDERDRAIN SYSTEM - 6 - SURFACE DRAINAGE - 7 - DRYWELL - 7 - LIMITATIONS - 7 - FIGURE 1 - LOCATION OF EXPLORATORY BORING FIGURE 2 - LOG OF EXPLORATORY BORING FIGURE 3 - GRADATION TEST RESULTS TABLE I- SUMMARY OF LABORATORY TEST RESULTS TABLE 2-PERCOLATION TEST RESULTS RECEIVED 12/11/2017 W-PkKUMAR ASPEN Project No. 1BZJ1t01NG DEPARTMENT PURPOSE AND SCOPE OF STUDY This report presents the results of a subsoil study for a proposed residence to be located at Lot 1, Block 6, Riverside Subdivision, 1300 Riverside Drive, 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 S2 Architects dated June 16, 2017. An exploratory boring was drilled 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. Verify the geotech has PROPOSED CONSTRUCTION reviewed the current plans and that their report is still accurate. At the time of our study, design plans for the residence had not been developed. The new residence is proposed in the existing building area. We assume excavation for the building will have a maximum cut depth of one level, about 10 feet below the existing ground surface. For the purpose of our analysis, foundation loadings for the structure were assumed to be relatively light and 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. RECEIVED 12/11/2017 H-PkKUMAR ASPEN Project No. ti3611POIJG DEPARTMENT - 2 - SITE CONDITIONS The property is occupied with a two story frame and stucco residence above a crawlspace and with an attached garage. The driveway is accessed from Fred Lane as shown on Figure 1. Vegetation consists of irrigated lawn with landscape trees, and grass and weeds along the lot perimeter. The ground surface is relatively flat with a slight slope down to the northwest. The lot is located about 500 feet northeast of the Roaring Fork River and around 20 feet above river level. FIELD EXPLORATION The field exploration for the project was conducted on July 5, 2017. One exploratory boring was drilled at the location shown on Figure 1 to evaluate the subsurface conditions. The boring was advanced with 4 inch diameter continuous flight augers powered by a truck-mounted CME-45B drill rig. The boring was logged by a representative of H-P/Kumar. Samples of the subsoils were taken with 1'/R 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 the driveway slab consist of clayey silty sand and gravel fill to 3 feet overlying medium dense to dense silty sand and gravel with cobbles to the boring depth of 21 feet. RECEIVED 12/11/2017 H-P%KUMAR ASPEN Project No. 17BZ 11NGDEPARTMENT - 3 - Laboratory testing performed on samples obtained from the boring included natural moisture content and density and gradation analyses. Results of gradation analyses performed on small diameter drive samples (minus 11/2 inch fraction) of the coarse granular subsoils are shown on Figure 3. The laboratory testing is summarized in Table 1. Verify drywell has 5' vertical separation from groundwater level Groundwater was encountered in the boring at 14 feet at the time of drilling and the upper soils were slightly moist to moist. Seasonal fluctuation and possible rise should be expected. FOUNDATION BEARING CONDITIONS The natural sand and gravel sols are adequate for support of spread footing foundations. Fill material and debris from previous site development should be removed from beneath the proposed building area. 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 chemical grouting, micro piles and soil nails should be feasible at the site. A shoring contractor should provide design drawings to support the proposed excavation slopes. Other City requirements may also be applicable. DESIGN RECOMMENDATIONS FOUNDATIONS Considering the subsurface conditions encountered in the exploratory borings and the nature of the proposed construction, we recommend the building be founded with spread footings bearing on the natural soils. The design and construction criteria presented below should be observed for a spread footing foundation system. RECEIVED 12/11/2017 H-P<KUMAR ASPEN Project No. 1$61POING DEPARTMENT - 4- 1) Footings placed on the undisturbed natural 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 10 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) All existing fill, debris, topsoil and any loose or disturbed soils should be removed and the footing bearing level extended down to the relatively dense natural soils. The exposed soils in footing area should then be moisture adjusted to near optimum 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 45 pcf for backfill consisting of the on-site soils. Cantilevered retaining structures which are separate from the residence 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 soils. RECEIVED 12/11/2017 H-P t KUMAR ASPEN Project No. t NteiNG DEPARTMENT - 5 - 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 0.50. 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 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, are suitable to support lightly loaded slab-on-grade construction. To reduce the effects of some differential movement, floor slabs should be RECEIVED 12/11/2017 H-P k KUMAR ASPEN Project No. 1 NtEDiNG DEPARTMENT - 6 - 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. UNDERDRAIN SYSTEM Free water was encountered during our exploration, and it has been our experience in the area that the water level can seasonally rise and 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 lower level of the residence should be placed at Ieast 3 feet above high groundwater level. 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 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' feet deep. RECEIVED 12/11/2017 H-P KUMAR ASPEN Project No. 1$BteilING DEPARTMENT - 7 - SURFACE DRAINAGE The following drainage precautions should be observed during construction and maintained at all times after the residence 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 3 inches in the first 10 feet in paved areas. Free-draining wall backfill should be covered with filter fabric and capped with about 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. DRYWELL We understand that a drywell or bio swale could be used for site runoff detention and disposal. The Natural Resources Conservation Service has identified four hydrologic soil groups (HSG) in the Aspen area and the site is located in Type B soil having a moderate infiltration rate. Results of a percolation test performed in Boring 1 are presented in Table 2. The groundwater level is relatively shallow and the bedrock is generally known to be relatively deep in this area. 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 implied. The conclusions and recommendations submitted in this report are based upon the data obtk CEIVED 12/11/2017 H-P#KUMAR ASPEN Project No. j$I? flG DEPARTMENT - 8 - 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, UMAR Louis E. Eller, Staff Engineer Reviewed by: P,41 sp16. •saoo. `• 96222 Steven L. Pawlak, r.Eb R . 1i ) LEE/kac ,eJtidLf3 :'6R) i'— RECEIVED 12/11/2017 H-P--KUMAR ASPEN Project No. 'T361MNG DEPARTMENT IA ISIT Rn 1 AIF1A tr Ir t 1/t MIMI' 3 LOCK rtu7lluresla:el LOT 9 I�Z. L 1.1\ I f �Astou' s,r -g1 rEAMt-t 71 9P'V �sros EI tOURD LAWSMIt i I-I 1 RIrIACrn woo A•A sR11AA 1r •I ` 01 1 1/+'1tl1Cw rbuItc CAY LSI7.I s 11 1 sY 0.1,41 GRA fllrrr " ^� 11:0i1R1'lIM reA A4nEogluT I I I RrcerrioeNO.4113. ..., -- BENCHMARK: ri.! I • •-- ,FINISH FLOOR GARAGE _ A I EL = 100', ASSUMED teeurrtti.SASM = _,e• ` 1 `_ rr 11N'1t110W I M lateen rl 1 l /� MASTIC CAP 5= r` 1s1761I •4 `\ �/� 2 STORY FRAME r `BORING 1 q \ . It ST1tLC0 'L.• '— ! TEO LCWt• 1I1 1 - NOILS7 G GIRAGS `.ti i1P1:tnAsm[PRne jv \ Arne tnlr•R.Iro rt7INV WWI 11•111 Z AITIAC[ON'I7R.D.s R[FIR is ^ 71 Ft I I'S il(Co'R'lt.tllr!LAP L51/:11 / •ACC 0 rrJJ// �' c N701)74511 1 \\ S E i; n 257 rlr' • `rIAGSrM.t r.1n : G�. E �S Ter.D.tAetuR 1. =�• nA1T1C CAP lSrl:i l ., LOT io z �� Lor G r-L1-41 r 1o,754a S.F. ( • 1'W!P[10/1.171t 4 •1/'M71t IV/ lc f`R,1[Ii A:r[[A3711e\7 RlyNrCfWeir Met 1111 Alta Ill 011171 Rt111 It 1 lir I IWO.;nAl/tr rArlp \1/i { 1[T A`t7 1 Fakir tr nrll ell lAr ll tl2ll --_— _.t rT-- .„-w 7926 •rT. $S145TTIn.ls 7y1.0 /l trl l+11elDx' ------. ,..4vq It.$71G CAN 121 R11 _�r. -- r slr[2etr _---~ �R — —ter P SI' __ ._ __ _ _. ...._ _ _- .- --1 a 1 wgo mi_Ram` c 15 0 15 30 R APPROXIMATE SCALE—FEET =F RECEIVED El l 17-7-501 H-PtiKUMAR LOCATION OF EXPLORATORY BORNG Figs 1111/2 017 ASPEN BUILDING DEPARTMENT BORING 1 LEGEND EL. 99.5' (4) CONCRETE, THICKNESS IN INCHES SHOWN IN PARENTHESES TO LEFT OF 0 (4) mum THE LOG. 4) Fupi • (4) "; BASECOURSE, THICKNESS IN INCHES SHOWN IN PARENTHESES TO LEFT ' 13/12 � OF THE LOG. 5 FILL; CLAY WITH SILTY SAND AND GRAVEL, MEDIUM DENSE, MOIST, MIXED 01 27/12 BROWNS. • WC=5.0 D0=127 _ -200=20 7 GRAVEL AND SAND (GM-SM); SILTY, COBBLES, MEDIUM DENSE TO • DENSE, MOIST TO WET WITH DEPTH. 0 . w - 10 — DRIVE SAMPLE, 2-1NCH I.D. CAUFORNIA LINER SAMPLE. 37/12 WC=6.6 - - +4=15 -200=23 DRIVE SAMPLE, 1 3/8-INCH 10. SPLIT SPOON STANDARD T PENETRATION TEST. o 27/12 DRIVE SAMPLE BLOW COUNT. INDICATES THAT 27 BLOWS OF A 15 140-POUND HAMMER FALLING 30 INCHES WERE REQUIRED TO DRIVE 18/12 THE SAMPLER 12 INCHES. — DEPTH TO WATER LEVEL ENCOUNTERED AT THE TIME OF DRILLING. —► DEPTH AT WHICH BORING CAVED FOLLOWING DRILING. — 20 22/12 +4=35 _ -200-13 NOTES I. THE EXPLORATORY BORING WAS DRILLED ON JULY 5, 2017 WITH A 4-INCH DIAMETER CONTINUOUS FLIGHT POWER AUGER. 25 2. THE LOCATION OF THE EXPLORATORY BORING WAS MEASURED APPROXIMATELY BY PACING FROM FEATURES SHOWN ON THE SITE PLAN PROVIDED. 3 THE ELEVATION OF THE EXPLORATORY BORING WAS MEASURED BY HAND LEVEL AND REFERS TO THE BENCHMARK ON FIG. 1. 4. THE EXPLORATORY BORING LOCATION AND ELEVATION SHOULD BE CONS DERED 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 LEVEL SHOWN ON THE LOG WAS MEASURED AT THE TIME AND UNDER CONDITIONS INDICATED. FLUCTUATIONS IN THE WATER • LEVEL MAY OCCUR WITH TIME. 7. LABORATORY TEST RESULTS; WC = WATER CONTENT (X) (ASTM 0 2216); DD = DRY DENSITY (pcf) (ASTM 0 2216); 1 +4 = PERCENTAGE RETAINED ON NO. 4 SIEVE (ASTM 0 422); -200 = PERCENTAGE PASSING NO. 200 SIEVE (ASTM 0 1140). 1a a= E9I ( EIVED 17--7-501 -{—P �MAR LOG OF EXPLORATORY BORING . s 12/11/2017 ASPEN BUILDING DEPARTMENT HYDROMETER ANALYSIS SIEVE ANALYSIS TIME READINGS U.S.STANDARD SERIES I CLEAII SQUARE OPENINGS 24 IRIS 7 N53 I t00 43 ION S MIN •YIN 1 MRN IN INN ! ! .• ! • !e0! . !f /la I ! 1.--- L T_- 0 50 lersas�ey ��____E___ — ~=�— -�11_ 10 I=Im liammw ---r .. ...1m..i _lim =riti,........071.........,1 _m _:� 30 al 40 I_I_j !! ! i! m....„.so 2 =1 ��1—t� ...=.eN— of7.1�1 lar"�'r. mi 70 10 EL linf0 "1111 I EMMEN so — o —1-1--ITT - I`I-I-1 17I—-I— t"T--1TrT 1--1-1-I T1'f 1—1— -1-ri -IT tau .001 .002 .005 .005 .015 .037 .07S .150 .300 1 .100 1.10 12.3. 4.75 9.9 10 30.1 75.2 127 200 I DIAMETER OF PARTICLES IN MILLIMETERS 1Io2 ' CLAY TO SILT SANG GRAVEL COBBLES FINE I MEDIUM 'COARSE FINE 1 COARSE GRAVEL 15 % SAND 62 X SILT AND CLAY 23 X LIQUID LIMIT PLASTICITY INDEX SAMPLE OF: Silty Send with Gravel FROM: Boring 1 0 10' HYDROMETER ANALYSIS SIEVE ANALYSIS TWO READINGS U.S.STANDARD SOWS I CLLR SQUARE OPENINGS 24 Me MS 100 42L9111.1 1!MIN 50J111 ISMIN ININ 'YIN ! .. too !30/pe 1l_11a l a • EPrLire So _,.. /=i=..— — - —t= - - - - � la —{— — - —i=- mr—- -- —I— ...—�-—---- —--- --—i 20 ----- C —L' - -- 70 30 —I— —1- —` =1=— =I= Z! —1—— se I —-- i— 1— - - `--1--•40 -- �C _--�--- - I- t _ = _ i I so ——y— - t 40 — I I i_-:w -- _ --F- -_— 1. 30 _. — _I _ 1- 70 - _.....-.I.. — ---- _ — _-==,=I: — —t v—i 20 40 --- — _ -- =r-= 112 .0 = --_ — ---_ f 0 —I-1--I"1"1" 1 .1—I-I-I-I-I rri—-I—-it'1 11,1 t--i-7-r-r-1 i i i a—I- III I I1"i-- ton .001 .e02 .005 .005 .015 .027 .075 .150 .300 I .800 1.10 12.35 4.71 5.3 IS 30.I 70.2 127 200 4 I DIAMETER OF PARTICLES IN MILLIMETERS 15 I SAND GRAVEL COBBLES CLAY TO SILT FINE 1 MEDIUM 1COARSE FINE COARSE A GRAVEL 35 X SAND 52 X S,LT AND CLAY 13 X I LIQUID LIMIT PLASTICITY NDEX Theme teat sauna apply only to Ihe SAMPLE OF: S:Ity Sand with Grovel FROM: Baring 1 0 20' sample■ which were tented. The Ifeslfngq reporl than not ba reproduced. ascepl In full, without the written approval of Kumar& Aaaoclatea• Inc Sieve analysis tealn0 la performed in == aecordanca wlh ASTM Dt22. *STY C13& ry and/or ASTN DI140. t.sk RECEIVED R ri Ir 17-7-501 H-P1KUMAR GRADATION TEST RESULTS F ig, 3 15 /2017 ASPEN BUILDING DEPARTMENT 0 ui A 03 v au 'i cs ca cz O c.. u. 1 z a 0 0 0 u .'=^. 0 0 3 3 �3 a 0 0 0 al cZ C V) Cr/ VD W I- T. W V u. Z d Z in W a LI z0its 7 uu I— CZ J l7 X < LLJ L J ILI W 2 LLJ ce CC W a a X O H Q O a W w m iz J M en co LL w7 w $ N N 6 z g N N = z IA a tiD In o vl a a . a a J CC — en ID Z I- 0 a N a Z cc a w 1- D Z -- Z 2 u I ZO W Y 0 0 r 0 Q u 9 J a o a Z 12/11/2017 ASPEN BUILDING DEPARTMENT H - PI<UMAR TABLE 2 PERCOLATION TEST RESULTS PROJECT NO. 17-7-501 _ T HOLE NO. HOLE LENGTH OF WATER WATER DROP IN AVERAGE DEPTH INTERVAL DEPTH AT DEPTH AT WATER PERCOLATION (INCHES) (MIN) START OF END OF LEVEL RATE INTERVAL INTERVAL (INCHES) (MIN./INCH) (INCHES) (INCHES) 1 124 5 42 373/4 5'/4 1.0 5 373/4 34 3% 1.3 2 34 33 ' 1 2 2 33 321/2 1/2 4 2 321/2 32 1/2 4 2 32 31'/a '/a 4 2 311/2 31 1/2 4 2 r 31 301/2 1/2 4 Note: The percolation test was conducted in the 4-inch diameter borehole of Boring 1 on July 5, 2017. RECEIVED 12/11/2017 ASPEN BUILDING DEPARTMENT