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HomeMy WebLinkAboutSubsoils Report for Foundation DesignGTLITHOMPSON .. - i'- ' -.' ' I '1'.,a,inr,,i,*l,tiii .ii '1;.1;';tfti'fi'.,' i:. t'l' 'l '., :. ''' ' l GEOTECHNICAL ENGINEERING INVESTIGATION !l': '::;. '\: a ' " '1:'l _i I "- "-l DUFFY RESIDENCE PARCEL 217915300489 COUNTY ROAD 331 GARFIELD COUNTY, COLORADO $ s \ dPrepared For: JONATHAN DUFFY 90 Mountain Shadows Drive Glenwood Springs, CO 81601 Attention: Jonathan Duffy Project No. GS06684.000-120 August 5,2022 CTllThompson, lnc. Denver, Fort C.ollins, @_S.pdngg, Glenwood Springs, Pqeblo, Summit Countv - Colorado Qhevenne, Wyoming and Bpzem?n, Montana ffi TABLE OF CONTENTS SCOPE SUMMARY OF CONCLUSIONS ...... SITE CONDITIONS PROPOSED CONSTRUCTION ..,.... strE GEoLOGY .......,... SUBSURFACE CONDITIONS.......... SITE EARTHWORK...,. Excavation Subexcavation and Structural Fill... Foundation Wall Backfill......,.... FOUNDAT|ON,..........,.... SLAB.ON.GRADE CONSTRUCTION, FOUNDATION WALLS SUBSURFACE DRAINAGE. SURFACE DRAINAGE CONCRETE CONSTRUCTION OBSERVATIONS . GEOTECHNICAL RISK LtMrrATtoNs ................ FIGURE 1-VICINITYMAP FIGURE 2 * AERIAL PHOTOGRAPH FIGURE 3 - SUMMARY LOGS OF EXPLORATORY P]TS FIGURE 4 - FOUNDATION WALL DRAIN CONCEPT TABLE I - SUMMARY OF LABORATORY TESTING JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO. GS06684.000-120 1 1 2 3 3 4 4 4 5 6 6 7 I I ffi SCOPE CTllThompson, lnc. (CTLIT) has completed a geotechnical engineering investigation for the Duffy Residence proposed on a parcel near County Road 331 in Garfield County, Colorado. We conducted this investigation to evaluate subsurface conditions at the site and provide geotechnical engineering recom- mendations for the potential construction. The scope of our investigation was set forth in our Proposal No. GS 22-0131 . Our report was prepared from data devel- oped from our field exploration, laboratory testing, engineering analysis, and our experience with similar conditions. This report includes a description of subsur- face conditions found in our exploratory pits and provides geotechnical engineer- ing recommendations for design and construction of the foundation, floor system, below-grade walls, subsurface drainage, and details influenced by the subsoils. A summary of our conclusions is below. SUMMARY OF CONCLUSIONS Subsurface conditions encountered in our exploratory pits exca- vated at the site were about 1.5 to 7 feet of sandy clay, underlain by weathered claystone to the total excavated depth of 8 feet. Ground- water was not found in our exploratory pits. 2.Variable subsurface conditions will be encountered at anticipated foundation elevation for the residence. To create more uniform sup- port conditions and reduce the potential for differential building movement, we recommend subexcavation of the soils and clay- stone material to a depth of 2 feet below footings. The excavated materials can be replaced as densely-compacted, structural fill. A slab-on-grade floor is anticipated in the basement level. To en- hance potentialfloor slab performance, we recommend subexcava- tion of the soil and claystone material below floor slabs to a depth of 2 feet and replacement as densely-compacted, structural fill' A foundation wall drain should be constructed around the perimeter of the building to mitigate water that infiltrates backfill soils adjacent 1 3 4 1JONATHAN DUFFY DUFFY RESIDENCE cTLlr PROJECT NO. GS06684.000-120 ffi to the residence, Site grading should be designed and constructed to rapidly convey surface water away from the building' SITE CONDITIONS The Duffy Residence is proposed on a 34-acre parcel (Parcel 21T915300489) in Garfield County, Colorado. The site is southeast of the inter- section of County Road 331 and Mineota Drive. A vicinity map with the location of the site is included as Figure , Ory",, 94i. on the south portion of the property. An aerial photograph of the site is shown on Figure 2. The residence is proposed south of a drainage swale that trends down to the west through the central part of the propefty. Ground surface in the area of the proposed resi- dence slopes down to the north and northwest at grades visually estimated be- tween 5 and 10 percent. Vegetation is predominantly sparse sage and grasses. A photograph of the site at the time of our subsurface investigation is below. Looking northwest at TP-1 JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO, GS06684.000-120 2 ffi PROPOSED CONSTRUCTION Architectural plans for the Duffy Residence were not developed at the time of our geotechnical engineering investigation. The residence is anticipated as a two-level building with the lowest level constructed as a walk-out basement' A slab-on-grade floor is expected in the basement level. Foundation excavation depths could be on the order of B to 12 feet at the uphill side of the building. Typi- cal foundation loads for the type of construction anticipated are about 2,000 to 3,000 pounds per linear foot of foundation wall with interior column loads of less than 50 kips. We should be provided with architectural plans, as they are devel- oped, so we can provide geotechnical/geo-structural engineering input. SITE GEOLOGY We reviewed geologic mapping by the U.S. Geological Survey (USGS) for the area of the property. This map was "Geologic Map of the Silt Quadrangle, Garfield County, Colorado", by Ralph R. Shroba and Robert B. Scott (dated 2001). The geologic mapping indicates that bedrock of the Shire Member of the Wasatch Formation is near the ground surface. The Shire Member is described as predominantly multicolored fine-grained clastic intervals of claystone, mud- stone, and siltstone interbedded with less abundant intervals of minor coarse- grained clastic beds of thin fluvial sandstone. The overburden soils at the site are likely alluvium and colluvium derived from the underlying Shire Member bedrock. The soils and weathered claystone found in our exploratory pits appear con- sistent with the descriptions on the geologic map. JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJEcT NO. GS06684.000-120 3 ffi SUBSURFACE CONDITIONS Subsurface conditions were investigated by directing excavation of two ex- ploratory pits (TP-1 and TP-2) at the site. The pits were excavated with a track- hoe on April 1 1,2022 at the approximate locations shown on Figure 2. Excava- tion operations were directed by our engineer, who logged subsurface conditions encountered and obtained representative samples. Graphic logs of subsurface encountered in our exploratory pits are included as Figure 3. Subsurface conditions encountered in our exploratory pits were about 1.5 to 7 feet of sandy clay, underlain by weathered claystone to the total excavated depth of 8 feet. Groundwater was not encountered in our pits at the time of exca- vation. The pits were backfilled immediately after exploratory excavation opera- tions were complete. Samples of the soils obtained from our exploratory borings were returned to our laboratory for pertinent testing, Engineering index testing on two samples of the weathered claystone indicated liquid limits of 29 to 30 percent and plastic- ity indices of 3 to 12 percent. Samples of the soil and weathered claystone tested had water-soluble sulfate contents of 0.42 percent and 0.68 percent, respec- tively, Laboratory testing is summarized on Table L SITE EARTHWORK Exgavation Our subsurface investigation and experience at nearby sites indicate ex- cavations at the site can be made with conventional, heavy-duty excavating equipment. Sides of excavations need to be sloped or retained to meet local, state, and federal safety regulations. The subsoils at the site will likely classify as JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO. G506684.000-',|20 4 ffi Type B soils based on OSHA standards governing excavations. The weathered claystone could classify as a Type A material. From a "trench" safety standpoint, temporary slopes deeper than 5 feet that are not retained should be no steeper than%to 1 (horizontal to vertical) in Type A soils and 1 to 1 in Type B soils. Con- tractors are responsible for determining the actual OSHA soil type when excava- tions are made and for maintaining safe excavations. Contractors should identify the soils encountered and ensure that OSHA standards are met. We do not anticipate excavations for the building foundation witl penetrate a free groundwater table. Excavations should be sloped to a gravity discharge or to a temporary sump where water from precipitation can be removed by pump- ing. Subexcavation and Structur4l Fill Variable subsurface conditions will be encountered at anticipated founda- tion elevation for the residence. To create more uniform support conditions and reduce the potential for differential building movement, we recommend subexca- vation of the soils and claystone material to a depth of 2 feet below footings and floor slabs and replacement as densely-compacted, structural fill. The subexca- vation process should extend laterally at least 1 foot beyond the perimeter of the building. The excavated soils and weathered claystone can be reused as structural fill material, provided they are free of rocks larger than 3 inches in diameter, or- ganic matter, and debris. As an alternative, an aggregate base course or pit run material can be imported to the site for use as structural fill. A sample of desired import soil should be submitted to our office for approval. Structuralfill materials should be moisture-conditioned to within 2 percent of optimum moisture content, placed in loose lifts of 8 inches thick or less, and JONATHAN DUFFY DUFFY RESIOENCE crLlT PROJECT NO. GS06684.000-120 5 ffi compacted to at least 98 percent of standard Proctor (ASTM D 698) maximum dry density. Moisture content and density of structural fill should be checked by a representative of our firm during placement. Observation of the compaction pro- cedure is necessary. Foundation Wall Backfill Proper placement and compaction of foundation wall backfill is important to reduce infiltration of surface water and settlement from consolidation of backfill soils. This is especially important for backfill areas that will support exterior con- crete slabs, such as the driveway and patios. The soils and weathered claystone excavated from the site can be used as backfill material, provided they are free of rocks larger than 4-inches in diameter, organics, and debris' Backfill soils should be placed in loose lifts of approximately 10 inches thick or less, moisture-conditioned to within 2 percent of optimum moisture con- tent, and compacted to at least 95 percent of standard Proctor (ASTM D 698) maximum dry density. Moisture content and density of the backfill should be checked during placement by a representative of our firm. Observation of the compaction procedure is necessary. FOUNDATION Variable subsurface conditions will be encountered at anticipated founda- tion elevation for the residence. To create more uniform support conditions and reduce the potential for differential building movement, we recommend subexca- vation of the soils and weathered claystone material to a depth of 2 feet below footings. The excavated materials should be replaced as densely-compacted, structuralfill in accordance with the Subexcavation and Structural Fill section. JONATHAN DUFFY DUFFY RESIDENCE crllr PROJECT NO. GS06684.000-{20 o TF Recommended design and construction criteria for footing foundations are provided below. These criteria were developed based on our analysis of field and laboratory data, as well as our engineering experience' Footings should be supported on a2-leetthickness of densely- compaited, structuralfill. The structural fill should be in accordance with recommendations in the Subexqavation and Structural Fill sec- tion. Footings on the structuralfill can be designed for a maximum net allowable soil bearing pressure of.3lQ00 psf*The weight of backfill soil above the footings can be neglected for bearing pressure cal- culation. A friction factor of 0.40 can be used to calculate resistance to slid- ing between concrete footings and the structuralfill' Continuous wall footings should have a minimum width of 16 inches. Foundations for isolated columns should have minimum di- mensions of 24 inches by 24 inches. Larger sizes may be required, depending upon foundation loads. Grade beams and foundation walls should be well-reinforced. We recommend reinforcement sufficient to span an unsupported dis- tance 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. The Garfield County building department should be consulted regarding frost protection requirements. SLAB.ON.GRADE CONSTRUCTION A slab-on-grade floor is anticipated in the basement level of the residence. Exterior concrete flatwork, such as the driveway and patios, will also likely be constructed, To enhance potential floor slab performance, we recommend subex- cavation of the soil and weathered claystone material below interior floor slabs to a depth of 2 feet and replacement with densely-compacted, structural fill. The JONATHAN DUFFY OUFFY RESIDENCE cTLlr PROJECT NO. GS06684.000-120 1 2 5 o 3 4 7 ffi subexcavated soils should be replaced as densely-compacted, structuralfill in accordance with recommendations in the Subexcavatjon anelStructural Fill sec- tion. Based on our analysis of field and laboratory data, as well as our engi- neering experience, we recommend the following precautions for slab-on-grade construction at this site. Slabs should be separated from wall footings and column pads with slip joints, which allow free vertical movement of the slabs. 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 and porch 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 American Concrete lnstitute (ACl) recommendations, to reduce problems associated with shrinkage and curling. The lnternational Building Code (lBC) may require a vapor retarder be placed between the base course or subgrade soils and concrete slab-on-grade floors. The merits of installation of a vapor retarder below floor slabs depend on the sensitivity of floor coverings and building to moisture. A properly installed vapor retarder (10 mil min- imum) is more beneficial below concrete slab-on-grade floors where floor coverings will be sensitive to moisture. FOUNDATION WALLS Foundation walls that 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. These factors include, but are not JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO. GS06684.000-120 1 2 3 4 5 B ffi limited to, the type, compaction, slope, and drainage of the backfill, and the rigid- ity 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 de- flect or rotate 0.5 to 1 percent of wall height (depending upon the backfilltypes), design for a lower "active" lateral earth pressure may be appropriate. Our experi- ence indicates typical below-grade walls in residences deflect or rotate slightly under normal design loads, and that this deflection results in satisfactory wall performance. Thus, the earth pressures on the walls will likely be between the "active" and "at-rest" conditions. For backfill soils conforming with recommendations in the Found?tion 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 as- sumes deflection; some minor cracking of walls may occur. lf very little wall de- flection is desired, a higher design value for the "at-rest" condition is appropriate using an equivalent fluid pressure of 60 pcf. SUBSURFACE DRAINAGE Water from precipitation and surface irrigation frequently flows through rel- atively permeable backfill placed adjacent to a building, and collects on the sur- face of less permeable soils at foundation elevation. This process can cause wet or moist conditions after construction. To reduce the likelihood water pressure will develop outside foundation walls and the risk of wetting in below-grade ar- eas, we recommend provision of a foundation wall drain around the perimeter of the addition. JONATHAN DUFFY DUFFY RESIDENCE crLlT PROJECT NO. GS06684.000-120 9 ffi The exterior foundation wall drain should consist of 4-inch diameter, slot- ted, pVC pipe encased in free-draining gravel. A prefabricated drainage compo- s1e should be placed adjacent to foundation walls. Care should be taken during backfill operations to prevent damage to drainage composites. We expect the drain will discharge to a drywell for dispersal. The foundation wall drain concept is shown on Figure 4. SURFACE DRAINAGE Surface drainage is critical to the performance of foundations, floor slabs, and concrete flatwork. Site grading should be designed and constructed to rap- idly convey surface water away from the residence. Proper surface drainage and irrigation practices can help control the amount of surface water that penetrates to foundation levels and contributes to settlement of foundations and slabs-on- grade. Positive drainage away from the foundation and avoidance of irrigation near the foundation also help to avoid excessive wetting of backfill soils, which can lead to increased backfill settlement and possibly to higher lateral earth pres- sures, due to increased weight and reduced strength of the backfill. We recom- mend the following precautions. The ground surface surrounding the exterior of the residence shouid be sloped to rapidly convey surface water away from the building in all directions. We recommend a minimum constructed slope of at least 12 inches in the first 10 feet (1 0 percent) in land- scaped areas around the residence. Backfill around the foundation walls should be moisture-treated and compacted pursuant to recommendations in the Foundation Wall Backfill section. We recommend that the residence be provided with roof gutters and downspouts, The downspouts should discharge well beyond the limits of all backfill. Splash blocks and/or extensions should be provided at all downspouts so water discharges onto the ground JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO. G506684.000-120 1 2 3 10 ffi beyond the backfill. We generally recommend against burial of downspout discharge PiPes' lrrigation should be limited to the minimum amount sufficient to ma'intain vegetation; application of more water will increase likeli- hood of slab and foundation movements. Plants placed close to foundation walls should be limited to those with low moisture re- quirements. 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 land- scaped areas adjacent to foundation walls. Geotextile fabric will in- hibit weed growth yet still allow natural evaporation to occur, CONCRETE Concrete in contact with soil can be subject to sulfate attack. We meas- ured water-soluble sulfate concentrations of 0.42 percent and 0.68 percent in two samples from this site (see Table l). For this level of sulfate concentration, ACI 332-08 Code Requirements for Residential Concrete indicates concrete shall be made with ASTM C 150 Type V cement, or an ASTM C595 or C1157 hydraulic cement meeting high sulfate-resistant hydraulic cement (HS) designation and shall have a specified minimum compressive strength of 3000 psi at 28 days. Al- ternative combination of cements and supplementary cementitious materials, such as Class F fly ash, shall be permitted with acceptable test records for sul- fate durability. ln our experience, superficial damage may occur to the exposed surfaces of highly-permeable concrete, even though 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% +l_ 1.5%. JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO. GS06684.000-120 4 11 ffi CONSTRUCTION OBSERVATIONS We recommend that CTLIT be retained to provide construction observa- tion and materials testing services for the project. This would allow us the oppor- tunity to verify whether soil conditions are consistent with those found during this investigation. lf others perform these observations, they must accept responsibil- ity to judge whether the recommendations in this report remain appropriate. lt is also beneficial to projects, from economic and practical standpoints, when there is continuity between engineering consultation and the construction observation and materials testing phases. GEOTECHNICAL RISK The concept of risk is an important aspect of any geotechnical evaluation. The primary reason for this is that the analytical methods used to develop ge- otechnical recommendations do not comprise an exact science. We never have complete knowledge of subsurface conditions. Our analysis must be tempered with engineering judgment and experience. Therefore, the recommendations pre- sented in any geotechnical evaluation should not be considered risk-free. We cannot provide a guarantee that the interaction between the soils and the pro- posed structure will lead to performance as desired or intended. Our recommen- dations represent our judgment of those measures that are necessary to in- crease the chances that the structure will perform satisfactorily. lt is critical that all recommendations in this report are followed. This report has been prepared for the exclusive use of the client. The in- formation, conclusions, and recommendations presented herein are based upon consideration of many factors including, but not limited to, the type of structures proposed, the geologic setting, and the subsurface conditions encountered. The conclusions and recommendations contained in the report are not valid for use JONATHAN DUFFY DUFFY RESIDENCE cTLIT PROJECT NO. GSo6684.000-120 12 ffi by others. Standards of practice continuously change in geotechnical engineer- ing. The recommendations provided in this report are appropriate for about three years. lf the proposed project is not constructed within three years, we should be contabted to determine if we should update this report. LIMITATIONS Our exploratory pits provide a reasonable characterization of subsurface conditions at the site. Variations in the subsurface conditions not indicated by pits will occur. We should be provided with architectural plans, as they are further de- veloped, so that 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 similar 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 report, please call. CTLITHoMPSON, INC Reviewed by: tu R.BLt-E.t R. Barbone, E.l.T. t s D. Kell ivision ManagProject Engineer rbarbone@ctlthom psn. com JONATHAN DUFFY OUFFY RESIDENCE cTLlr PRoJECT NO. GS06684.000-120 13 tr 0 500 1000 NOTE: SCALE: 1'- 1000' JONATHAN DUFFY IX,FFY FESIDENOE SATELLITE IMAGE FROM MAXAR (CoPYRTGHT 2021) Vicinity Map County Rood 331 County Rood 346 Duffy Residence PROJECT NO. GSO6684.OOO-1 20 Flg. 1 LEGEND: TP-1I ffi 0 50 100 SCALE: 1'= 100'NOTE: JONATHAN DUFFY DUFFY RESIDENCE PROJECT NO. GSO6684.O00-1 20 APPROXIMATE LOCATION OF EXPLORATORY PIT APPROXIMATE LOCATION OF PROPERTY BOUNDARY SATELLITE IMAGE FROM GOOGLE TMAGERY (COPYRIGHT 2022) Aerial Photograph Flg. 2 TP.1 10 15 JONATHAN DUFFY DUFFY RESIDENCE PROJECT NO. GS06684.000-120 TP-2 ffi 0 0 LEGEND: 5 z CI.AY, SANDY, MEDIUM STIFF, MOIST, TAN' BROWN. (cL) WEATHERED CLAYSTONE, MEDIUM HARD' BROWN' GRAY, RUST. BULK SAMPLE FROM EXCAVATED SOILS AND BEDROCK.F Flrl lrJl! I TF o- u,lo Ful uJl! IF o_lrlo 10 15 NOTES: 1. EXPLORATORY PITS WERE EXCAVATED WITH A TRACKHOE ON APRIL 11,2022. 2. GROUNDWATER WAS NOT ENCOUNTERED IN OUR EXPLOMTORY PITS AT THE TIME OF EXCAVATION. PITS WERE BACKFILLED IMMEDIATELY AFTER EXPLOMTORY EXCAVATION OPERATIONS WERE COMPLETED. 3. THESE LOGS ARE SUBJECT TO THE EXPI-ANATIONS. LIMITATIONS AND CONCLUSIONS IN THIS REPORT. Surnmary Logs of Fi[E'"ratory FIG.3 tr 2-3' f*r*o\ PREFABRICATED SLOPE osFn @\,ER ENNRE WDTH OF BELOIY-GRA,DE I{AII suP .,olNI PER DRAI}IAGE COMPOS]IE (MTRADRAIN 6000 oR EQUMA.$IT) GRAVEL WIH NON-WOVEN GEOTECNIE FABRIC (MIRAFI r{oN oR EauvALEt{t). ATTACH PI.ASTIC SHEENNG TO FOUNDANON MINIMUM OR BEYOND ENCASE PIPE IN GRA\EL DOEND AI.ID AT I,EAST E}MRE MENCH JO[{ATI-!AN DUFFY OUFFY RESIDENCE PROJECT NO. GSO6684.OOO-1 20 Foundation Wall Drain Concept 1:1 SLOPE FROM BOTTOM OF FOONNG (wHrcHEtER F eneATER) 4-INCH DTAITEIER PERFORATED RIGID DRAIN PIPE. THg PIPE SHOUL.D BE PIACED IN A TRENCH ffITI A sLoPE oF AT tEAst lrla-lNcH DRoP PER FOOT OF DRAIN. I/2. TO 1-1/2. SCREENED dmva urrERrurv ro FooTlNc 1/2 H$GW OF FOONNG. RI.L WIIH GRAVE- NOIE THE BOTTOM OF THE DMIN SHOULD BE AT LEASr 2 NCUFS BEIOIV BOTTOM 0F itpnHc'AT"ntt ttionesr ronn ano sLoPE DowNwARD T9 A Foslltvu GRAvITY buiiii-ciR fo A SUMF wneie wATER cAll BE REMcTED FY PUMPING. 7,t Fls,4 TABLE I SUMMARY OF LABORATORY TESTING PROJECT NO. GS06684.000-1 20 ffi DESCRIPTION CLAY. SANDY (CL) WEATHERED CLAYSTONE WEATHERED CLAYSTONE WEATHERED CLAYSTONE PASSING NO.200 SIEVE f/o\ 80 36 SOLUBLE SULFATES (%l 0.42 0.68 ATTERBERG LIMITS PLASTICITY INDEX (%\ 12 I LIQUID LIMIT (o/o\ 29 30 DRY DENSITY (PCF) MOISTURE CONTENT (%\ DEPTH (FEET) 34 7-8 34 7-8 EXPLORATORY BORING TP-1 TP-1 TP-2 TP-2 Page 1 of 1