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Home My WebLink AboutSubsoil Studyffi CTLITHOMPSON YEARS FOUNÐEÐ TN 197.1 CTL I THOMPSON ffi GEOTECHNICAL ENGINEERING INVESTIGATION 565 FARANHYLL RANCH ROAD (A.K.A. PARCEL #4, FARANHYLL RANCH) GARFIELD COUNTY, COLORADO Prepared For: GREEN LINE ARCHITECTS 65 N.4th Street, Suite 5 Carbondale, CO 81623 Project No. GS0657 2.000-120 luly 1,2021 234 Center Drive I Glenwood Springs, Colorado 81601 Telephone: 970-945-2809 Fax: 970-945-741 1 Jt lrtLtII rrllrllrlrrtrl-II lll ffi TABLE OF CONTENTS scoPE..,.... SUMMARY OF CONCLUSIONS SÍTE CONDITIONS PROPOSED CONSTRUCTTON .................. GEOLOGY AND GEOLOGIC HAZARDS.... SUBSURFACE CONDITIONS........... SITE EARTHWORK....... Excavations Subexcavation and Structural FiI|............. Foundation Wall Backfill FOUNDAT|ONS.............. SLAB-ON-GRADE CONSTRUCTION ......... CRAWL SPACE CONSTRUCTION............. FOUNDATION WALLS SUBSURFACE DRAINAGE............... SURFACE DRAINAGE CONCRETE CONSTRUCTION OBSERVATIONS STRUCTURAL ENGINEERING SERVICES GEOTECHNICAL RISK.,..... LIMITATIONS FIGURE 1-VICINITYMAP FIGURE 2 - AERIAL PHOTOGRAPH FIGURE 3 - PROPOSED CONSTRUCTION FIGURE 4 - SUMMARY LOGS OF EXPLORATORY BORINGS AND PITS FIGURE 5 _ SWELL-CONSOLIDATION TEST RESULTS FIGURE 6 - GRADATION TEST RESULTS FIGURE 7 AND 8 - FOUNDATION WALL DRAIN CONCEPTS TABLE I _ SUMMARY OF LABORATORY TESTING GREEN LINE ARCHITËCTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000-120 .... 10 ....10 1 1 2 3 3 4 6 6 6 7 I o 11 12 13 13 14 14 15 ffi SCOPE CTL I Thompson, lnc. has completed a geotechnical engineering investiga- tion for the property at 565 Faranhyll Ranch Road (a.k.a. Parcel #4, Faranhyll Ranch) in Garfield County, Colorado. We conducted this investigation to evaluate subsurface conditions at the site and provide geotechnical engineering recom- mendations for the proposed construction. The scope of our investigation was set forth in our Proposal No. GS 21-0186. Our report was prepared from data devel- oped from our field exploration, laboratory testing, engineering analysis, and our experience with similar conditions. The report includes a description of subsurface conditions encountered in our exploratory boring and pits and provides geotech- nical engineering recommendations for design and construction of the building foundations, floor systems, below-grade walls, subsurface drainage systems, and details influenced by the subsoils. A summary of our conclusions is below. SUMMARY OF CONCLUSIONS Subsurface conditions encountered in our exploratory boring and pits consisted of about I inches of topsoil and 4.5 to 5.5 feet of sandy clay, underlain by clayey gravel, cobbles, and boulders. Groundwater was not found in our exploratory boring and pits at the time of our subsurface investigation. Based on geologic mapping and our engineering experience, the sandy clay and clayey gravef have potentialfor moderate to high amounts of consolidation when wetted under buildíng loads. We judge the residence and ADU/garage can be constructed on footing foundations, provided the soils below footings are sub-excavated to a depth of at least 3 feet and replaced as densely-compacted, struc- turalfill. 1 2 3. GREEN L¡NE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. G506572.000-120 4 To enhance potential performance of floor slabs in buildings at the site, we recommend subexcavation of the soils below slabs to a depth of at least 3 feet and replacement with densely-compacted, structuralfill. A foundation wall drain should be constructed around the perimeter of below-grade areas of the buildings to mítigate surface water that infíltrates backfill soils adjacent to the foundations. Site grading 1 ffi should be designed and constructed to rapidly convey surface water away from the buildings. SITE CONDITIONS The site is located at 565 Faranhyll Ranch Road (a.k.a. Parcel#4, Faranhyll Ranch) in Garfield County, Colorado, A vicinity map with the site location is includ- ed as Figure 1. The property is at the base of the east flank of the Grand Hogback. The lot is an approximately 35-acre parcelthat is predominantly west of Faranhyll Ranch Road. The new buildings are proposed in the west part of the property, south of an existing residence. An aerial photograph of the west part of the parcel, including the existing residence is shown on Figure 2. Ground surface in the areas of the proposed buildings generally slopes down to the northeast at grades visually estimated at about 10 percent. The subject area of the site is an irrigated hayfield. A photograph of the proposed building site at the time of our subsurface investiga- tion is below. GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000.120 Looking east across proposed building site 2 ffi PROPOSED CONSTRUCTION Architectural plans for a proposed single-family residence and an ADU/garage building were being developed at the time of our geotechnical engi- neering investigation. The residence is anticipated as a one and two-story building. We understand that garage and storage space in the uphill (west) side of the resi- dence will have a slab-on-grade main level floor with no below-grade areas. The downhill (east) side of the residence will have a structurally-supported floor with a crawl space below. Preliminary plans indicate the main level of the ADUlgarage building will be a slab-on-grade. The uphill (west) side of the building will retain earth. We expect maximum foundation excavation depths of about I to 10 feet. Foundations loads are likely to be on the order of 1,000 to 3,000 pounds per linear foot of foundation wall with maximum interior column loads of less than 75 kips. We should be provided with architectural plans, as they are further developed, so we can provide geotechnical/geo-structural engineering input. GEOLOGY AND GEOLOGIC HAZARDS We reviewed the geologic map by the Colorado Geology Survey (CGS), ti- tled, "Geologic Map of the Cattle Creek Quadrangle, Garfield County, Colorado", by Kirkham, Streufert, Hemborg, and Stelling (dated 2014). The area of the subject property is mapped as intermediate debris flow deposits of the Holocene and Pleistocene Epochs. The sandy clay and clayey gravel soils found in our explora- tory boring and pits are consistent with the descriptíon of the debris flow deposits. Due to the depositional method, the debris flow deposits have not been subject to significant geologic loads. These soils are prone to consolidation when wetted un- der building loads. We judge the debris flow deposits have potential for moderate to high amounts of consolidation when wetted under building loads. We also reviewed the CGS map "Collapsible Soils and Evaporite Karst Hazard Map of the Roaring Fork Valley, Garfield, Pitkin and Eagle Counties", by GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000-120 3 ffi Jonathan L. White (dated 20A2). The surficial soils at the site are mapped as un- consolidated, whích possess potentialfor hydrocompaction when wetted, especial- ly under building loads. CGS has mapped the approximate location of a historical occurrence soil settlement on Four Mile Road about 1 mile southeast of the sub- ject site. Formation of sinkholes is random and can occur anywhere and at any time in the geologic environment at this site and cannot be predicted. The degree of risk related to sinkholes cannot reasonably be quantified. We díd not observe obvious visual evidence of sinkhole/subsidence formations on or immediately ad- jacent to the subject property. We are not aware of buildings in the immediate vi- cinity of the property that have experienced recent subsidence-related damage. We rate the potential risk of sinkhole development at the site as low. SUBSURFACE CONDITIONS Subsurface conditions were investigated by directing drilling of one explora- tory boring (TH-1) and observing the excavation of two exploratory pits (TP-1 and TP-2) at the site. The approximate location of the boring and pits are shown on Figures 2 and 3. Our boring was drilled on May 6,2021 with soild-stem auger and a track-mounted drill rig. The pits were excavated on May 21,2021with a track- hoe. Exploratory drilling and excavation operations were directed by our engineer, who logged the soils encountered in the boring and pits and obtained representa- tive samples. Graphic logs of the soils encountered in our exploratory boring and exploratory pits are shown on Figure 4. Subsurface conditions encountered in our exploratory boring and pits con- sisted of about I inches of topsoil and 4.5 to 5.5 feet of sandy clay, underlain by clayey gravel, cobbles, and boulders. Groundwater was not found in our explorato- ry boring and pits at the time of our subsu¡face investigation. PVC pipe was in- stalled in our boring and pits, prior to backfilling, to facilitate subsequent checks of groundwater. A photograph of conditions exposed in TP-1 is below. GREËN LÍNE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06s72.000-120 4 ffi Conditions exposed in TP-1 Samples of the soils obtained from our exploratory boring and pits were re- turned to our laboratory for pertinent testing. One sample of sandy clay selected for one-dimensional, swell-consolidation testing exhibited 0.3 percent swellwhen wetted under a load of 1,000 psf. Swell-consolidation test results are shown on Figure 5. One sample of the clayey gravel selected for gradation analysis con- tained 29 percent gravel, 32 percent sand, and 39 percent silt and clay (passing the No. 200 sieve). Gradation test results are not inclusive of rocks larger than 5 inches, which are present in the in-situ clayey gravel. Gradation test results are shown on Figure 6. One sample of the sandy clay tested had a water-soluble sul- fate content of 0.00 percent. Laboratory testing is summarized on Table l. GREEN LINE ARCHITÊCTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06s72.000.1 20 5 ffi SITE EARTHWORK Excavations Based on our subsurface investigation, we expect excavations for the pro- posed construction at this site can be accomplished using conventional, heavy- duty excavating equipment. Excavations deeper than 5 feet must be braced or sloped to meet local, state, and federal safety regulations. The sandy clay soilwill likely classify as Type B soil and the clayey gravel likely classifies as a Type C soil pursuant to OSHA standards governing excavations. Temporary excavations should be no steeper than 1 to 1 (horizontal to vertical) in Type B soils and 1.5 to 1 in Type C soils. Contractors are responsible for site safety and providing and maintaining safe and stable excavations. Contractors should identify the soils en- countered in excavations and ensure that OSHA standards are met. Free groundwater was not encountered in our exploratory boring and pits at the time of our subsurface investigation. We do not anticipate excavations to con- struct the proposed buildings will penetrate a free groundwater table. To mitigate water from precipitation, excavations should be sloped to gravity discharges or be directed to temporary sumps where water can be removed by pumping. Subexcavation and Structural Fill Based on our field and laboratory data from the site, and our engineering experience, the sandy clay and clayey gravel (i.e., debris flow deposits) at the site have potential for moderate to high amounts of consolidation when wetted under building loads. We judge the residence can be constructed on a footing foundation with slab-on-grade floors, provided the soils below footings and floor slabs are sub-excavated to a depth of at least 3 feet and replaced as densely-compacted, structuralfill. The subexcavation process should extend at least 1 foot beyond the perimeter of the building footprint. CTL should be called to observe conditions in GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000-1 20 6 ffi the foundation excavations, prior to placement of structural fill The subexcavated soils should be replaced with densely-compacted, granular, structuralfill. The soils excavated from the site can be reused as struc- tural fill, provided they are free of rocks larger than 3 inches in diameter, organic matter, and debris. lmported structural fill should consist of an aggregate base course or pit run with a maximum rock size of 3 inches. A sample of desired import soil should be submitted to our office for approval. The subexcavated soils, free of organic matter, debris and rocks larger than 3 inches in diameter can be re-used as structuralfill. The structural fill soils should be placed in loose lifts of B inches thick or less and moisture-conditioned to within 2 percent of optimum moisture content. Structural fill should be compacted to at least 98 percent of standard Proctor (ASTM D 698) maximum dry density. Mois- ture content and density should be checked by a representative of our firm during placement. Observation of the compaction procedure is necessary, Foundation Wall Backfill Proper placement and compaction of foundation backfill is important to re- duce infiltration of surface water and settlement of backfill. This is especially im- portant for backfill areas that will support concrete slabs, such as driveways and patios. The excavated soils free of rocks larger than 4 inches in diameter, organics and debris can be reused as backfill adjacent to foundation wall exteriors. Backfill should be placed in loose lifts of approximately 10 inches thick or less, moisture-conditioned to within 2 percent of optimum moisture content and compacted. Thickness of lifts will need to be about 6 inches if there are small, con- fined areas of backfill, which limit the size and weight of compaction equipment. We recommend backfill soils be compacted to 95 percent of standard Proctor (ASTM D 698) maximum dry density. Moisture content and density of the backfill GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572,000-120 7 ffi should be checked during placement by a representative of our firm. Observation of the compaction procedure is necessary. FOUNDATIONS Based on geologic mapping and our engineering experience, the sandy clay and clayey gravel have potentialfor moderate to high amounts of consolida- tion when wetted under building loads. We judge the residence and ADU/garage can be constructed on footing foundations, provided the soils below footings are sub-excavated to a depth of at least 3 feet and replaced as densely-compacted, structural fill. The structuralfill should be in accordance with recommendations in the Subexcavation and Structural Fill section. Recommended design and construction criteria for footings are below, These criteria were developed based on our analysis of field and laboratory data, as well as our engineering experience, The residence and ADU/garage can be constructed on footing foun- dations that are supported by an at least 3-feet thickness of densely- compacted, structural fill. The structuralfill should be in accordance with recommendations in the Subexcavation and Structural Fill sec- tion. Footings supported by the densely-compacted, structural fill can be designed for a maximum net allowable soil bearing pressure of 3,000 psf. The weight of backfill soils above the footings can be neglected for bearing pressure calculation. A friction factor of 0.40 can be used to calculate resistance to sliding between concrete footings and the structuralfill. Continuous wall footings should have a minimum width of at least 16 ínches. Foundatíons for isolated columns should have minimum OiÍ mensions of 24 inches by 24 inches. Larger sizes may be required, depending upon foundation loads. GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. G306572.000-t20 1 2 3. 4. I ffi Grade beams and foundation walls should be well reinforced to span undisclosed loose or soft soil pockets. We recommend reinforcement sufficient to span an unsupported distance of at least 12 feet. The soils under exterior footings should be protected from freezing. We recommend the bottom of footings be constructed at a depth of at least 36 inches below finished exterior grades for frost protection The Garfield County building department should be consulted re- garding required frost protection depth. SLAB-ON.GRADE CONSTRUCTION Slab-on-grade floors are planned in parts of the residence and ADU/garage, To enhance potential performance of floor slabs, we recommend subexcavation of the soils below slabs to a depth of at least 3 feet and replacement with densely- compacted, structural fill. The structuralfill should be in accordance with recom- mendations in the Subexcavation and Structural Fill section. Based on our analysís of field and laboratory data, as well as our engineer- ing experience, we recommend the following precautions for slab-on-grade con- struction at this site. Slabs should be separated from footings and columns pads with slip joints which allow free vertical movement of the slabs. The use of underslab plumbing should be minimized, Underslab plumbing should be pressure tested for leaks before the slabs are constructed. Plumbing and utilities which pass through slabs should be isolated from the slabs with sleeves and provided with flexible couplings to slab supported appliances. Exterior patio slabs should be isolated from the building. These slabs should be well-reinforced to function as independent units. Frequent controljoints should be provided, in accordance with Amer- ican Concrete lnstitute (ACl) recommendations, to reduce problems associated with shrinkage and curling. GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GSo6572.000-120 5 6 1 2 3 4. I ffi CRAWL SPACE CONSTRUCTION The main level floor in the downhill (east) part of the residence is proposed as structurally-supported by the foundation walls with a crawl space below the floor. Building codes normally require a clear space of at least 18 inches between ex- posed earth and untreated wood floor components. For non-organic systems, we recommend a minimum clear space of 12 inches. This minimum clear space should be maintained between any point on the underside of the floor system (including beams, plumbing pipes, and floor drain traps and the soils. Utility connections, including water, gas, air duct, and exhaust stack connec- tions to appliances on structural floors should be capable of absorbing some deflec- tion of the floor. Plumbing that passes through the floor should ideally be hung from the underside of the structural floor and not laid on the bottom of the excavation. lt is prudent to maintain the minimum clear space below all plumbing lines. lf trench- ing below the lines is necessarv, we recommend sloping these trenches, so they discharge to the foundation drain. Control of humidity in crawl spaces is important for indoor air quality and performance of wood floor systems. We believe the best current practices to con- trol humidity involve the use of a vapor retarder or vapor barrier (10 mil minimum) placed on the soils below accessible subfloor areas. The vapor retarder/barrier should be sealed at joints and attached to concrete foundation elements, FOUNDATION WALLS Foundation walls which extend below-grade should be designed for lateral earth pressures where backfill is not present to about the same extent on both sides of the wall, such as in basements and crawl spaces. Many factors affect the values of the design lateral earth pressure on below-grade walls. These factors GREEN LINE ARCHITECTS 555 FARANHYLL RANCH ROAD PROJECT NO. G506572.000-120 t0 ffi include, but are not limited to, the type, compaction, slope and drainage of the backfill, and the rigidity of the wall against rotation and deflection. For a very rigid wall where negligible or very little deflection will occur, an "at-rest" lateral earth pressure should be used in design. For walls that can deflect or rotate 0.5 to 1 percent of wall height (depending upon the backfilltypes), lower lateral earth pressures approaching the "active" condition may be appropriate. Our experience indicates typical below-grade walls in residences deflect or rotate slightly under normal design loads, and that this deflection results in satÍsfactory wall performance. Thus, the earth pressures on the walls wíll likely be between the "active" and "at-rest" conditions. For backfill soils conforming with recommendations in the Foundation Wall Backfill section that are not saturated, we recommend design of below-grade walls at this site using an equivalent fluid density of at least 45 pcf. This value assumes some deflection; some minor cracking of walls may occur. lf very little wall deflec- tion is desired, a higher design value closer to the "at-rest" condition may be ap- propriate, For the on-site soils, an at-rest lateral earth pressure of 60 pcf is rec- ommended. These equivalent densíties do not include allowances for sloping backfill, surcharges or hydrostatic pressures. SUBSURFACE DRAINAGE Water from precipitation, snowmelt, and irrigation frequently flows through relatively permeable backfill placed adjacent to a residence and collects on the surface of less permeable soils at the bottom of foundation excavations. This can cause wetting of foundation soils, hydrostatic pressures on below-grade walls and wet or moist conditions in below-grade areas, such as basements and crawl spac- es after construction. To mitigate problems wíth subsurface water, we recommend construction of a foundation wall drain around the perimeter of below-grade areas of the proposed buildings. This includes the ADU/garage wall that will retain earth. GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GSo6572.000-120 11 ffi The foundation wall drains should consist of 4-inch diameter, slotted PVC pipe encased ín free-draining gravel. A prefabricated drainage composite should be placed adjacent to foundation walls. Care should be taken during backfill opera- tions to prevent damage to drainage composites. The drains should discharge via positive gravity outlets or lead to sumps where water can be removed by pumping. Gravity outlets should not be susceptible to clogging or freezing. lnstallation of clean-outs along the drainpipes is recommended. The foundation wall drain con- cepts are shown on Figures 7 and 8. SURFACE DRAINAGE Surface drainage is critical to the performance of foundations, floor slabs and concrete flatwork. Site grading should be designed and constructed to rapidly convey surface water away from the buildings. Proper surface drainage and irriga- tion practices can help control the amount of surface water that penetrates to foundation levels and contributes to settlement or heave of soils and bedrock that support foundations and slabs-on-grade. Positive drainage away from the founda- tions and avoidance of irrigation near the foundations will also help to avoid ex- cessive wetting of backfill soils, which can lead to increased backfill settlement and possibly to higher lateral earth pressures, due to increased weight and reduced strength of the backfill soils. We recommend the following precautions. The ground surface surrounding the exterior of the buildngs should be sloped to drain away from the buildings in all directions. We rec- ommend a minimum constructed slope of at least 12 inches in the first 10 feet (10 percent) in landscaped areas around the buildings. Backfill around the foundation walls should be moistened and com- pacted pursuant to recommendations in the Foundation Wall Backfill section. We recommend the buildings be provided with roof gutters and downspouts. Roof downspouts should discharge well beyond the lim- its of all backfill. Splash blocks and/or extensions should be provided 1 2 3 GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GSo6572.000-120 12 ffi= at all downspouts so water discharges onto the ground beyond the backfill. We generally recommend against burial of downspout dis- charge. Where it is necessary to bury downspout discharge, solid, rigid pipe should be used, and the pipe should slope to an open gravity outlet. Landscaping should be carefully designed and maintaíned to mini- mize irrigation. Plants placed close to foundation walls should be lim- ited to those with low moisture requirements. lrrigated grass should not be located within 5 feet of the foundation. Sprinklers should not discharge within 5 feet of foundations. Plastic sheeting should not be placed beneath landscaped areas adjacent to foundation walls or grade beams. Geotextile fabric will inhibit weed growth yet still allow natural evaporation to occur. CONCRETE Concrete in contact with soil can be subject to sulfate attack. We.measured a soluble sulfate concentration of 0.00 percent in a sample of soil from the site (see Table l). For this level of sulfate concentration, ACI 332-08 "Code Require- ments for Residential Concrefe" indicates there are no special cement require- ments for sulfate resistance in concrete in contact with the subsoils. ln our experience, superficial damage may occur to the exposed surfaces of highly permeable concrete, even when sulfate levels are relatively low. To control this risk and to resist freeze-thaw deterioration, the water-to-cementitious materials ratio should not exceed 0.50 for concrete in contact with soils that are likely to stay moist due to surface drainage or high-water tables. Concrete should have a total air content of 6 percent +/- 1.5 percent. We recommend all foundation walls and grade beams in contact with the subsoils be damp-proofed. CONSTRUCTION OBSERVATIONS We recommend that CTL I Thompson, lnc. be retained to provide construc- tion observation and materials testing services for the project. This would allow us the opportunity to verify whether soil conditions are consistent with those found 4 GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. G506572.000-120 t3 ffi during this investigation. lf others perform these observations, they must accept responsibility to judge whether the recommendations in this report remain appro- priate. lt is also beneficíalto projects, from economic and practical standpoints, when there is continuity between engineering consultation and the construction observation and materials testing phases. STRUCTURAL ENGINEERING SERVICES CTL I Thompson, lnc. is a full-service geotechnical, structural, materials, and environmental engineering firm. Our services include preparation of structural framing and foundation plans. We can also design temporary and permanent earth retention systems. Based on our experience, CTL I Thompson, lnc. typically pro- vides value to projects from schedule and economic standpoints, due to our com- bined expertise and experience with geotechnical, structural, and materials engi- neering. We can provide a proposal for structural engineering design services, if requested. GEOTECHN¡CAL RISK The concept of risk is an important aspect with any geotechnical evaluation primarily because the methods used to develop geotechnical recommendations do not comprise an exact science. The analytical tools which geotechnical engineers use are generally empirical and must be tempered by engineering judgment and experience. Therefore, the solutions or recommendations presented in any ge- otechnical evaluation should not be considered risk-free and, more imporlantly, are not a guarantee that the interaction between the soils and the proposed struc- tures will result in performance as desired or intended. The engineering recom- mendations in the preceding sections constitute our estimate of those measures necessary to help the buildings perform satisfactorily. GREEN LINE ARCHIÌECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000-120 '14 ffi This report has been prepared for the exclusíve use of the client. The infor- mation, conclusions, and recommendations presented herein are based upon consideration of many factors íncluding, but not limited to, the type of structures proposed, the geologic setting, and the subsurface conditions encountered. Standards of practice continuously change in the area of geotechnical engineer- ing. The recommendations provided are appropriate for about three years. lf the proposed project is not constructed within three years, we should be contacted to determine if we should update this report. LIMITATIONS Our exploratory boring and pits provide a reasonable characterization of subsurface condítions at the site. Variations in the subsurface conditions not indi- cated by the boring and pits will occur. We should be provided with architectural plans, as they are further developed, so we can provide geotechnical/geo- structural engineering input. This investigation was conducted in a manner consistent with that level of care and skill ordinarily exercised by geotechnical engineers currently practicing under símilar conditions in the locality of this project. No warranty, express or im- plied, is made. lf we can be of further service in discussing the contents of this re- porl, please call. cTL I THOMPSON, lN D. Kellogg,,z\ision Manager í1 åGOa JDK:abr GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. c506s72.000-t 20 ','/(; iilIlL 15 ffi 0 1500 ¡000 NOTE: SCALET l'- 5000' GREEN LINEARCHITECTS ı35 Fa¡anMl Hanah Road PROJECT NO. GSO6572.OOO-1 20 SATELLITE IMAGE FROM GOOGLE EARTH (DATED JUNE 2017) Vicinity Map Glenwood Springs 565 Forcnhyll Ronch Rood Flg. 1 0 r00 200 LEGEND: TP-- 1il ,:l NOTE: ffiAPPROXIMATE LOCATION OF EXPLORATORY PIT APPROXIMATI LOCATION OF EXPLORATORY BORING APPROXIMATE LOCATION OF PROPERTY BOUNDARY SATTLLITE IMAGT FROM GOOGLI EARTH (DATED JUNE 2017) SCALE: 1" : 200' GREEN LINE ARCHITECTS 565 FaranMl Rsnch Road PROJECT NO. GSO657 2.OOO-1 20 Aerial Photograph Flg. 2 APPROXIMATE LOCATION EXPLORATORY PIT APPROXIMATE LOCATION EXPLORATORY BORING BASE DRAWING BY GREEN LINE ARCHTTECTS (DATED APRTL 14, 2021 NOTE: GREEN LINE ARCHITECTS 635 Falanhll Ranch Road PROJECT NO. GSO6572.OOO-1 20 LEGEND: TP_1 T Tt-l-,1û ffi OF OF 0 ) I 1 rt ttrl l\ I 4 .l I t ïH*r1 I ts I ( \t t- Í ¡ ,t. t\ t\ It TP_2 I I I ! I I I I I I ! I I I I I I ¡ I I ¡ ¡ I I I I ! I I I I I I I I ¡ I I I. ItI t I I II I ll tÌìr ll II tt I I tl t I I I I tl lt tl rl tt tt ll tt t I It Ì tj !l ti I I I I I ¡ .l'¡ i, I I I¡ I I I I I ll t¡ tt 1 ! ìl Proposed Construction Fþ 3 ¡¡- o,; I , I ¡ I ¡ lr lI l¡ ll ll ll TH-1 TP.1 10t12 36/5.5 10 15 GREEN LINEARCHITECTS 565 FARANHYLL RANCH ROAD TP-2 TF 00 55 LEGEND: n TOPSOIL, CLAY, SANDY, SILT, DARK BROWN, ORGANICS. CLAY. SANDY, MEDIUM STIFF, MOIST, BROWN, DARK BROWN. (CL) f-tlltu r tsú u..to t-t¡lul LL -Fo- IIJo GRAVEL, CLAYEY, SAND. COBBLES, BOULDERS, MEDIUM DENSE, MOIST, BROWN, GRAY. (GC, SC) DRIVE SAMPLE, THE SYMBOL 1O/l2INDICATES 1O BLOWS OF AN AUTOMATIC 14O.POUND HAMMER FALLING 30 INCHES WERE REQUIRED TO DRIVE A 2.5.INCH O.D, CALIFORNIA.BARREL SAMPLER 12 INCHES. INDICATES BULK SAMPLE FROM EXCAVATED SOILS. PRACTICAL SOLID.STEM AUGER REFUSAL ON COBBLES AND BOULDERS. NOTES EXPLORATORY BORING WAS DRILLED ON MAY 6, 2021 WITH 4-INCH DIAMETER, SOLID-STEM AUGER AND A TRACK-MOUNTED DRILL RIG. THE BORING WAS BACKFILLED IMMEDIATELY AFTER EXPLORATORY DRILLING OPREATIONS WERE COMPLETED. 2. EXPLORATORY PITS WERE EXCAVATED ON MAY 21, 2021WITH A TRACKHOE. THE PITS WERE BACKFILLED IMMEDIATELY AFTER EXPLORATORY EXCAVATION OPERATIONS WERE COMPLETED. 3. GROUNDWATER WAS NOT FOUND IN EXPLORATORY BORING OR PITS AT THE TIME OF DRILLING AND EXCAVATION. PVC PIPE WAS INSTALLED IN OUR BORING AND PITS, PRIOR TO BACKFILLING, TO FACILITATE SUBSEQUENT CHECKS OF GROUNDWATER- 4. LOCATIONS OF OUR EXPLORATORY BORING AND PITS AREAPPROXIMATE. 5. THESE LOGS ARE SUBJECT TO THE EXPLANATIONS, LIMITATIONS, AND CONCLUSIONS CONTAINED IN THIS REPORT. 10 15 þ F T Logs of lp¡r" 4CTLIT PROJECT NO. GS06572.000-120 Summarv Explorató Boring an FIG ffi 1 6 4 3 2 0 -2 -3 $.+ Øz O- -(X" IJJ àez^o-o6Ø LUÉ.-L-l Eoo -a 0.1 APPLIED PRESSURE . KSF Somple of CLAY, sANDy (cL) 10 DRY UNITWEIGHT= MOISTURE CONTENT= 109 19.4 Swell-Consolidation Test Results 100 PCF o/oFromTH-'I AT 4 FEET GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000-1 20 k r r t|ll EXPANSION UNDER CONSTANT PRESSURE DUE TO WETTINGllll l | illl) \ \) 1.0 FIG.5 ffi SANDS GRAVELctAY (PLAST|c) TO StLT (NON-plAsflc) FINE MÊDIUM COARS FINÉ COARSE COSBLÉS ANALYSIS SIEVE ANALYSIS 0 10 20 30 40 50 60 70 80 90 80 970ıu) Í60 Fz 850úu¿40 30 20 10 0 z -¡_ -t_ -|-|-__a¿---+.- _t_ _t_ oúzIfi É. F2uoú.uè ,4 100 .001 0.002 .005 .009 ,019 .037 s.52 19.1 36.1 76.2 12752200 5'6'8" TIME READINGS 60 MtN. 19 MtN. 4 MtN. 1 MtN. .200 U.S, STANDARD SERIES '100 '50 .40 .30 .16 .10 .8 CLEAR SOUARE OPENINGS 3/8" 3t4" 1yl, 3. .074 .149 .297 .590 1,19 2.0 2.38 4.76o.42 DIAMETER OF PARTICLE IN MILLIMETERS 90 100 25 HR. 7 HR, 45 MtN. 15 MtN. Somple of From SAND, CLAYEY (SC) TP - 1 AT 8-9 FEET GRAVEL srlr a clÃV PLASTICITY INDEX SAND t-touro Lur¡lr 32 o/o % % 29% 39 o/o SANDS GRAVÊLcLAY (PLAST|C) TO StLT (NON-pLAST|C) FINÊ MEDIUM COARS FINE COARSE COEBLES ANAL 10 20 30 40 50 60 70 80 90 100 --l-l-- '200 '4100 90 80 (noz6a ff60t-z ss0 É. UIÀco .001 0.002 .005 .009 .019 .037 9.52 19.1 36.1 76.2 12-t ,2oO152 TIME READINGS 60 MlN. 19 MtN. 4 MtN. I MtN. U,S. STANDARO SERIES '100 '50 ,40 .30 .16 .10 .8 CLEAR SQUARE OPENINGS 3t8" 3t4" 1y," 3" 5'6" 30 20 10 0 .o74 .149 .297 .590 1.19 2.0 2.38 4.76o.42 DIAMETER OF PARTICLE IN MILLIMETERS 29 ¡p. 7 HR. 45 MtN. 15 MtN. Somple of From GREEN LINE ARCHITECTS 565 FARANHYLL RANCH ROAD PROJECT NO. GS06572.000-1 20 GRAVEL SILT & CLAY PLASTICITY INDEX Yo SANDo/o LIQUID LIMIT o/o % To Gradation Test Results FIG.6 ffi SLOPE 2-3' SLOPE OSHA PER *:n BELOW-GRADE WAtt SUP JOINT DRA¡MCE coMPosm (unnonruN oooo OR EAUMAI..EI.IT} ATTACH PI.ASNC SHEENNG TO FOUNDATION MINIMUM OR BEYOND 1:1 SLOPE FROM BOTTOM OF FOOTNG (TYH|CHEVER tS GREATER) tlNçH DtAl,tEtER PERFORITTED RtctD DRA¡N ptpE. TTIE PIPE SHOUTD BE PT.ACEÐ N ¡ rNg{CN WrH ô_glopE oF AT tEASr 1,/S-|NCH DROP pER FOOT OF DRAIN. ENqASE ptpE tN 1/2. rO 7-1/2. SCREENED GRAIEL ÐfiEND G-RAvEL ureñrurv To FoonNG 4!8 AT LE st 1/2 HETGF|Í OF FOOTTNG. Rtr ET{NRE TRENCH tTH GRA\EL NOÏE: 'rltE_BorToM oF THE DRATN SHOUT"D BE AI rEASr 2 NCHES BELOW BOTTOM OFIeTlNc _^r'mE HrcHEsr poNT AÌ.rD sLopF DotvNwARD-tb A-Fosihw-ðiviWorrTrET oR To A suup TvHERE wATER c,Alr BE nendeo-rv'pi¡mpñè. GHEEN uNEABCHlteCTS 685 FARANÞMJ- RANCH ROAD PROJECT NO. GSO6 572.OOO-1 20 Foundation Wall Drain Concept Ftg.7 tr DMIMGE coMPosm ATTACH PI,.ASTIC SHEETING TO FOUNDANON wAu-SLOPE OSHA COIÆR ET,TTIRE WDTH OF PER //- }RAWL SPACE J GRAVEL WITH NON-TYOVEN CEOTÞfiLE FABRIC (MIRAFI l¡tON OR EAUMAIE]IÌ).RECOMMENDED BARRIER ET MINIMUM OR BEYOND 1¡1 SLOPE FROM BOTTOM OF FOOTING (|YHTCHEVER tS GRFÂTER) !:ttcH D|AI|EIER PERFORATED DRATN ptpE THEPIPE SHOUI.D BE PI.ACED IN A TRENCN WM N SLoPE OF AT tEASf î/E-INCH DROP pER FOOTOF DRAIN. ENqÞE PIPE lN 1/2'TO 1-t/2' SCREETì|EDGRAIEL ÐfiEND GRAVEL I"ATEHÄ.TY TO FOOTNG 4!p AT LEìsr 1/2 HHcHr OF FOOÌ|NG. Ru- ENNRE TRENCH IT|TII GRAì/E. NOTE: qE4N SHOUI..D BE AI I¡Aqf 2 NCHES BELOW BOTTOM OF FOOTNG ATTHE HIGHEST POINT AI'¡D SLOPE DOWNWARD TOï ÉOËirIVL 'GRAVFY OUTLET OR TO A SUMP ÌVHERE WAIER C¡'N EE RNIOVEó'Fr ÞUUPI¡¡C. GREEN LINEARCHfTECTS 565 FARAN}ÍYII RANCH ROAD PROJECT NO. cSO657 2.OOO-1 20 Foundation Wall Drain Concept STRUCTURqL FLOOR '{. Fls.8 TABLE ISUMMARY OF LABORATORY TESTINGPROJECT NO. GS06572.000-120ffiDYCLAYSANDYPASSINGNO- 200SIEVE(o/o\773986PERCENTSAND(o/o\32PERCENTGRAVEL(e/o\29SOLUBLESULFATES(o/o\0.00-SWELL(%\0.3IERG LIMITSPLASTIC'TYINDEX(o/o\ATTEFLIOUIDLIMIT(%\DRYDENSITY(PCF)109MOISTURECONTENT(o/a\19.4DEPTH(FEET)45-6B-94-57-8EXPLORATORYBOR¡NG AND PITTH.,'TP-1TP-1ÎP-2- SWELL MEASURED WITH IOOO PSF APPLIÊD PRESSURE.NEGATIVE VALUE INDICATES COMPRESSION,Page 1 of 1