Attachment 6 Kitty Hawk Geotech Report.pdf

August 23, 2010

Geotechnical Engineering Investigation Report Cedar City Kitty Hawk Maintenance Building Dixie NF

To Whom It May Concern:

This report presents the geotechnical findings for the proposed Maintenance and Vehicle Shop within the interagency property located at 1770 West Kitty Hawk Drive in Cedar City, Utah. The objectives of this study were to define subsurface soil and groundwater conditions, then prepare recommendations regarding site grading and foundations. A summary of our findings include:

• Onsite fine grained soils (silts/sands/clays) extending to depths of up to five feet are severely collapsible when they become saturated or nearly saturated. These potentially collapsible soils are not suitable for the support of the proposed structure and must be completely removed under such. However, these potentially collapsible soils may remain in flexible pavements if the upper 18-inches are scarified and compact to the requirements of structural fill. The collapsible soils were found along the south benched portion of the site, and decrease in thickness to the north.

• If fine grained soils are encountered at base of foundation excavation or underneath rigid pavements (Portland Cement Concrete), they must be completely remove and replace with structural fill, extending to native granular soil.

• The allowable bearing pressure for conventional spread footings placed on native undisturbed granular soil or structural fill extending to native undisturbed granular soil is 3,500 psf.

• No groundwater was encountered during investigation.

• All soils supporting foundations or pavements are to be inspected by a Forest Service representative before the placement of footings, floorslabs, or rigid pavements. If soil conditions are different from what was observed in this report, our office is to be notified for site specific recommendations.

If you have questions regarding this report or desire additional information please contact us.

Sincerely, Todd Touchard, P.E.

Geotechnical Engineer

USFS Intermountain Region

(801) 625-5224 ttouchard@fs.fed.us

INTRODUCTION 1

Figure 1. Vicinity Map 1

2.0 PROPOSED CONSTRUCTION 2

3.0 FIELD AND LABORATORY INVESTIGATION 2

3.1 Field Investigation 2

Figure 2. Maintenance Shop Building Location and Testpit Locations. 2

3.2 Laboratory Investigation 2

4.0 SITE CONDITIONS 3

Picture 1. Testpit 1. 3

4.1 Surficial Soils 3

4.2 Subsurface Soils 4

Picture 2.Testpit 2. 4 Picture 3. Testpit 3. 5

4.3 Groundwater 5

5.0 DESIGN RECOMMENDATIONS 5

5.1 Foundations 6

5.2 Estimated Settlement 6

5.3 Collapsible Soils 6

Table 1. Collapse Laboratory Data 7

5.4 Soil Class 7

5.5 Ground Motions 7

5.6 Lateral Soil Pressures & Resistance 8

5.7 Liquefaction & Faults 8

5.8 Floor Slabs and Exterior Rigid Pavements 9

5.9 Cement Types 9

5.10 Pavement 9

6.0 GENERAL CONSTRUCTION PROCEDURES AND RECOMMENDATIONS 10

6.1 Foundation Excavations 10

6.2 Subgrade Stabilization 10

6.3 Flexible Pavement Subgrade Preparation 10

6.4 Fill Installation & Compaction 11

6.5 Soil Special Inspection & Testing 11

Table 2. Minimum Frequency of Soil Inspection & Testing. 11

6.6 Aggregate Base Course 12

6.7 Granular Fill 12

7.0 LIMITATIONS 12

Geotechnical Investigation Cedar City Maintenance Shop

INTRODUCTION

This report presents the geotechnical findings for the proposed storage maintenance and vehicle building at the interagency site in Cedar City, Utah. The location of the site and proposed building is shown on Figures 1 and 2, respectively. The objectives of this study were to define subsurface soil and groundwater conditions, and prepare recommendations regarding site grading, foundations, earthwork, and seismic parameters.

To accomplish the objectives, a field investigation program and laboratory analysis of soil encountered at the site were conducted. The locations of the testpits are presented in Figure 2. The testpit logs are shown in Figures 3A-3C. A legend to log symbols and additional soil information is provided in Figure 4.

If the proposed type of structures, location of structures, or use of pavements change, our office shall be notified to review and potentially change recommendations contained in this report. This report should not be used for any other lots, buildings, or structures without prior approval.

Figure 1. Vicinity Map

SITE

2.0 PROPOSED CONSTRUCTION

The proposed construction is an approximate 4,000 square foot office and vehicle maintenance building.

Maximum wall and column loads are anticipated to be 2 to 4 kips per foot and 30 and 50 kips, respectively.

3.0 FIELD AND LABORATORY INVESTIGATION

3.1 Field Investigation

To define the subsurface soil and groundwater conditions, we completed three testpits (TP-1, TP-2, and TP-3) using a mini tracked excavator. Soils were classified in the field and later verified with laboratory testing as needed. Testpits were completed to a required maximum depth of 9-feet below grade.

Groundwater was not encountered in any of the testpits.

Figure 2. Maintenance Shop Building Location and Testpit Locations.

3.2 Laboratory Investigation

For soil classification and engineering properties, the samples obtained from exploratory borings were laboratory tested. Typical laboratory tests include:

• Moisture Content

• Soil Density

• Sieve Analysis

TP-3

TP-2

TP-1

N

• Fine Particle Size Analysis

• Atterberg Limits

• Consolidation Tests

Laboratory test data is shown on the individual Logs and is attached.

4.0 SITE CONDITIONS

The building site grades downward to the north and is covered with native ankle to knee high vegetation.

Grade changes fromthe south side of the site to the north is approximately 3 to 4 feet. The site is surrounded by similar undeveloped land.

Picture 1. Testpit 1.

4.1 Surficial Soils

The higher bench area (typically located on the south side of the site) is comprised of a thick surface layer of sandy silt. The silt is medium dense, dry, brown, and laboratory results indicate that it is highly collapsible when saturated. These potentially collapsible soils will be variable in thickness and lateral extend across the siteThe silt layer was approximately two to four inches thick at Tespit 1 and 2 locations, and extended to five below the surface at Testpit 3. At Testpit 3, laboratory testing shows that sandy silt is collapsible (9.7%). These highly collapsible soils are not suitable for the support of foundations, floor slabs, or rigid concrete pavements. These potentially collapsible soils may remain in flexible pavement areas if they are properly prepared as discussed later within this report.

4.2 Subsurface Soils

The subsurface soils were relatively consistent at the testpit locations. Beneath the topsoil/surficial soil, there isalluvial fine to coarse sandy fine and coarse gravel with numberous cobbles which extend to the full depth explored (9’ below the surface). The sandy gravels are medium dense to dense, slightly moist, brown, and are anticipated to exhibit high strength and low compressibility under the anticipated loads.

An approximate one-foot thick layer of Silty Clay was observed at seven feet below the surface in Testpits 2 and 3. The clay is medium stiff, slightly moist, brown, and anticipated to exhibit moderately low strength and moderately high compressibility under the anticipated loads.

Picture 2.Testpit 2.

Picture 3. Testpit 3.

4.3 Groundwater

Groundwater was not encountered at the Testpit locations at the time the fieldwork was completed. It is anticipated that surface water from spring rain will be the concern for this site. Depending on site grading and time of construction, surface runoff water and soft soils may be encountered at pavement subgrades and may require stabilization. Subgrade stabilization is discussed in Section 6.2.

5.0 DESIGN RECOMMENDATIONS

The following recommendations have been developed on the basis of the previously described project characteristics and subsurface conditions. A technical design review should be made by this office if actual loads are greater than anticipated or if there is any change in project criteria, including building location on the site.

The primary aspect that will influence the design and construction of the proposed project are the potentially collapsible soils that were encountered to depth of five feet below the existing ground surface.Under no circumstances should footings, floor slabs, or exterior rigid concrete pavements be installed upon potentially collapsible, non-engineered fills, loose or disturbed soils, sod, rubbish, construction debris, frozen soil, or other deleterious materials. If unsuitable soils are encountered, they must be completely removed and replaced with compacted granular fill. If granular soils become loose or disturbed, they must be recompacted prior to pouring the concrete. The width of replacement fill should be equal to the footings plus one foot for each foot of fill thickness.

Prior to the placement of footings, granular site grading fill, or floor slabs, the exposed natural subgrade must be proofrolled by passing moderate-weight rubber tire-mounted construction equipment over the surface at least twice. If any loose, soft, or disturbed zones are encountered, they must be completely removed in footing and floor slab areas and replaced with granular structural fill.

5.1 Foundations

Foundations should not be designed for more than the maximum allowable soil bearing pressures and other soil strength properties below. The allowable bearing pressure may be increased by 1/3 for temporary loads such as wind or seismic forces.

Recommended design parameters:

• Minimum Depth of Exterior 30 inches Footings and Unheated Areas

• Minimum Depth of Interior Footings 14-16 inches

• Recommended Minimum Width for 12 inches Continuous Wall Footing

• Recommended Minimum Width for 24 inches Isolated Spread Footing

• Recommended Allowable Bearing Pressure* 3,500 psf

*The provided bearing capacity is based on footings placed on native sandy gravel soil or structural fill extending to native sandy gravel.

5.2 Estimated Settlement

The anticipated maximum total settlement of foundations designed using the previously mentioned structural loads will be on the order of one-half to five-eights of an inch. Differential settlement is not expected to exceed 1/2-inch.

5.3 Collapsible Soils

Collapsible soils undergo a large volume change upon saturation. Collapsible soils in Utah typically are caused by mudflow deposits and alluvial fans produced by intermittent stream flows. The Cedar City area historically has had issues with alluvial deposited collapsible soils. On-site sandy silts in Testpit 3 were identified as being collapsible. Laboratory tests are shown below:

Table 1. Collapse Laboratory Data Location Soil Type Moisture

Content In-Situ Dry Density % Collapse

TP-3

3’ below surface

Silty Sand 3.5 89 pcf 9.7%

As previously mentioned, collapsible soils are not suitable for the support of foundations, floor slabs, or exterior rigid concrete/pavements. However, these potentially collapsible soils may remain in flexible pavement area if the upper18-inches is scarified and recompaced prior to the placement of the flexible pavement section. All water should be directed away from all pavements to prevent subgrade from becoming saturated.

5.4 Soil Class

For dynamic structural analysis, the Site Class D – Stiff Soil Profile as defined in Table 1613.5.2, Site Class Definitions, of the IBC 2009 can be utilized.

5.5 Ground Motions

At the time of this report, USGS website (earthquake.usgs.gov) did not provide 2009 IBC ground motion parameters. However, the 2009 IBC and 2006 IBC both reference 2005 ASCE Standard 7 for seismic design and mapping parameters. At the time of design, the Structural Engineer should verify if ground motion parameters should be based on 2002 or 2008 USGS maps.

The following table, based on USGS 2002 maps, summarizes the peak ground and short and long period accelerations for a MCE event and incorporates a soil amplification factor for Site Class D soil profile in the second column. Based on the site latitude and longitude (37.698 degrees north and -113.085 degrees west, respectively), the values for this site are shown below.

Spectral Acceleration Value, T Seconds

Site Class B-C Boundary

[mapped values] (% g)

Site Class D [adjusted for site class effects] (% g)

Peak Ground Acceleration 28.2 34.9

0.2 Seconds, (Short Period Acceleration) SS = 70.6 SMS = 87.2

1.0 Seconds (Long Period Acceleration) S1 = 22.3 SM1 = 43.6

The IBC 2009 code design accelerations (SDS and SD1) are based on multiplying the above accelerations (adjusted for site class effects) for the MCE event by two-thirds (⅔).

5.6 Lateral Soil Pressures & Resistance

Lateral soil pressures are dependent on the type of soil present. The pressures are based on a granular fill being used as backfill. The values below assume that the surface of the soils slope behind the wall is horizontal, and that the granular fill has been placed and lightly compacted, not as a structural fill. The following equivalent fluid lateral soil pressures shall be used for design:

1. Use 55 pcf for the static at-rest case. That is when the wall is not allowed to yield.

2. Use 35 pcf for active static case. Full active pressures only develop when the wall is allowed to move a sufficient distance. For granular soil, the typical movement range is 0.001 to 0.004H, and a cohesive soil is 0.01 to 0.04H, where H is the height of the wall.

3. Use 300 pcf for the static passive case. That is when the wall exerts pressure on the soil.

For the determination of lateral resistance for continuous and spread footings placed on granular structural fill, a friction value of 0.45 may be used for ultimate lateral resistance.

5.7 Liquefaction & Faults

Liquefaction is the result of saturated soils being shaken causing soil particles to easily move, resulting in loss of soil strength and stiffness. Due to the relative density of the site soils, type of soil, and the lack of shallow groundwater, the potential for liquefaction at the site is considered low.

The Cedar City-Parowan monocline fault system is mapped approximately 2 mile to the east of the site by the United States Geologic Survey (USGS). The USGS (http://earthquakes.usgs.gov) provide information regarding this fault. Selected text from these organizations is provided below:

Synopsis: The Cedar City-Parowan monocline (and faults) comprise a poorly understood zone of Holocene(?) deformation that may form a structural bridge between the Hurricane [998] and Paragonah [2534] faults. The monocline is near the boundary between the Basin and Range and Colorado Plateau provinces.

Geologic Setting: This complex zone of deformation is between the Hurricane [998] and Paragonah [2534] faults along the southeast side of Parowan Valley. Parowan Valley is at the southern edge of an area underlain by extrusive Tertiary volcanic rocks once continuous from near Pioche, Nevada, to Marysvale in Piute County. Some volcanic cover has been eroded to expose pre-existing topography of Paleozoic and Mesozoic sedimentary rocks. Limited depth penetration observed for some small-scale structures in the area supports a model of thin-skinned extensional response to major uplift of the plateau block. The possibility exists that a blind, plateau-bounding, normal fault zone with significant seismic potential underlies the main mountain-front monocline.

Length: 25 km.

Most recent prehistoric deformation: Latest Quaternary (<15 ka).

Slip rate: 0.2 and 1.0 mm/yr.

Comments: Hecker (1993 #642) indicates a minimum long-term deformation rate for uplift of 0.25 mm/yr due to folding in the central part of the monocline. Hecker (1993 #642) believes a displacement rate of 10 mm/yr, as reported by the geodetic survey, seems reasonable for the Holocene faults. This rate is so much greater than that reported anywhere else in the Basin and Range province that we believe if may represent some short-term phenomena that is not representative of the faults Holocene history or is not related to crustal faulting.

5.8 Floor Slabs and Exterior Rigid Pavements

All concrete slabs and rigid pavements placed on grade should be placed over 4” minimum, of ½” to 1” diameter, poorly graded, clean, free-draining gravel. Below the 4” gravel layer shall be properly placed site grading fill extending to native undisturbed granular soil. Potentially collapsible soils are not suitable for the support of floor slabs and concrete pavements and must be completely removed under such. All structural fill supporting slabs should be placed in 8-inch loose lifts and compacted to 95% of modified proctor.

5.9 Cement Types

The laboratory tests indicate that the native soils contain a low amount of water soluble sulfates (19.5 ppm) and a pH of 8.4. Therefore, no special requirements are needed for cement type.

5.10 Pavement

The natural fine-grained soils, which will be the typical pavement subgrade south of the maintenance shop, will exhibit poor pavement support characteristics when saturated. Where these potentially collapsible soils exist, they must be scarified to a depth of a minimum of 18-inches, moisture condition, and compact to 95% of modified proctor before placing aggregate base course.

The following flexible pavement sections, based on projected traffic conditions, are recommended:

Flexible Pavements (Asphalt Concrete): Parking Areas/ Access Roads

Moderate Volume of Automobiles and Light Trucks with Occasional Medium-Weight Trucks;

No Heavy-Weight Trucks [1 equivalent 18-kip axle load per day]

3.0 inches Asphalt concrete

8.0 inches Aggregate base course

18 inches Properly prepared potentially collapsible soils if encountered

Over Native Sandy Silts or Sandy Gravel

6.0 GENERAL CONSTRUCTION PROCEDURES AND RECOMMENDATIONS

The guidelines outlined below address the geotechnically related construction concerns for this project.

6.1 Foundation Excavations

Prior to placement of the foundations and floor sections, all areas that will support foundation loads or pavements should be inspected to insure that all potentially collapsible soils, loose, soft or otherwise undesirable material is removed and that the structures will bear on satisfactory material. All topsoil, fill and other deleterious materials underneath the proposed structure and pavement should be removed.

All foundation excavations should be protected against any detrimental change in condition such as disturbance, rain and freezing. Surface runoff should be directed away from the excavation and not allowed to pond. If possible, all footing concrete should be poured the same day as the excavation is made. If this is not practical, the foundation excavation should be adequately protected and foundation placement should take place as soon as possible.

6.2 Subgrade Stabilization

If construction practices or weather conditions during the placement of the fill caused the native soils become soft in pavement areas one of the following should be done:

• Remove areas where clays or silts are disturbed and place an additional 18-inches of granular fill (crushed or pit-run gravel), gradation requirements are shown in Section 6.7.

• Or place Geotextile grid between the undisturbed native soil and fill material to achieve proper compaction of the fill layers. Follow manufacture’s recommendations for lap length and installation. Manufacturer, type, and properties of geotextile grid used shall submitted to geotechnical engineer for approval prior to construction.

6.3 Flexible Pavement Subgrade Preparation

In flexible pavement areas, collapsible and unsuitable soils may be encountered during site grading operations. In areas where native fine grained soils will be used as the pavement subgrade, scarify the top 18-inches, moisture condition, and compact. If proofrolling identifies soft spot areas, remove to a minimum depth of two feet and replaced with compacted granular structural fill.

6.4 Fill Installation & Compaction

All fills supporting structural loads, pavements, or slabs should be compacted to at least 95 percent of the Modified Proctor maximum density (ASTM D 1557). The compaction should be accomplished by placing the fill in 8-inch loose lifts and mechanically compacting each lift to the specified minimum density. Fill shall be moisture conditioned within two percent of optimum moisture. Field density tests should be performed on each lift as necessary to insure that compaction is being achieved.

Subsequent to stripping and prior to placing pavement base, the subgrade should be prepared as discussed in Section 6.3 of this report.

All utility trench backfill below structurally loaded facilities (flatwork, floor slabs, roads, etc.) must be placed at the same density requirements established for structural fill. In these areas, backfill material shall consist of granular fill.

If the surface of the backfill becomes disturbed during the course of construction, the backfill should be proofrolled and/or properly compacted prior to the construction of any exterior flatwork over a backfilled trench. Proofrolling may be performed by passing moderately loaded rubber tire-mounted construction equipment uniformly over the surface at least twice. If excessively loose or soft areas are encountered during proofrolling, they should be removed to a maximum depth of two feet below design finish grade and replaced with structural fill.

6.5 Soil Special Inspection & Testing

As required by 2009 International Building Code, special inspections and testing shall be performed by an agency independent of the Contractor. During fill placement, the special inspector shall determine that proper materials and procedures are used in accordance with this report. Furnish all inspection and testing reports to Engineer.

Table 2. Minimum Frequency of Soil Inspection & Testing.

Inspection/Test Method Frequency Verify materials below shallow foundation are adequate to achieve bearing capacity.

Periodic

Verify excavations are extended to proper depth and have reached proper material.

Periodic

Verify use of proper materials, densities and lift thickness during placement and compaction of fill. (ASTM D 1557, D 422, D 2922)

Perform proctor test (ASTM D 1557) at start of project for each type of soil being compacting or when material appears to change.

Submit particle size analysis (ASTM D 422) data for approval before any import fill material is delivered or when fill material appears to change.

Inspection/Test Method Frequency Test compaction using nuclear density methods (ASTM D 2922) a minimum of: per 100 lf of backfill and each lift for trenches, every 800 sf and each lift for pavements base and subbase, and as directed by Engineer.

Prior to placement of compacted fill, observe subgrade and verify site has been properly compacted.

Periodic

6.6 Aggregate Base Course

For the base material directly below pavement, we recommend a granular soil free of organic or other deleterious material. We recommend a graded sand and fractured gravel material having between 5 and 11 percent passing the #200 sieve and no particles greater than approximately 1-1/2 -inches in maximum dimension. The minimum CBR value (ASTM B1883) of 80% is required.

6.7 Granular Fill

Granular soils free of organics, debris, or other deleterious materials are recommended for use as granular fill at this site. Granular fill is defined as a well graded sand and gravel material (pitrun or crushed gravel), with less than 15 percent passing the #200 sieve and no particles greater than 4 inches in maximum dimension.

Granular fill should not exhibit plasticity characteristics. Approved soil types as defined using the Unified Soil Classification are considered to be GW, GP, or GM or combinations thereof. Submit proposed fill material samples and sieve analysis to Engineer prior to placement. See Figure 4 for soil type definitions.

7.0 LIMITATIONS

The recommendations provided herein were developed by evaluating the information obtained from the testpits. The testpit data reflects the subsurface conditions only at the specific location at the particular time designated on the testpit log. Soil and ground water conditions may differ from conditions encountered at the actual testpit locations. The nature and extent of any variation in the testpit may not become evident until during the course of construction. If variations do appear, it may become necessary to re-evaluate the recommendations of this report after we have observed the variation.

Our professional services have been performed, our findings obtained, and our recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices. This warranty is in lieu of all other warranties, either expressed or implied.

Enclosures: Appendix :

Figure 3A-3C : Logs of Testpits Figure 4 : Soil Classification Chart Laboratory Analysis Data

TESTPIT

Page: 1 of 1

Project Name:

Location:

Excavation Method:

Elevation:

Remarks:

Project No.:

Forest:

Date Excavated:

Water Level:

FIGURE

US Forest Forest Service Region 4 324 25th Street Ogden, Utah 84401

G ra ph ic al L og

W at er L ev el

DESCRIPTION

D E

PT

H

F T

SA

M

PL

E

T Y

PE

SP

T

B L

O W

S/

FT

M O

IS

T

U R

E

P

A

SS

IN

G

D R

Y D

E N

SI

T

Y

(P C

F)

L iq ui d

L im it

Pl as tic L im it

REMARKS

-1

Cedar City Maintenance Shop Kittyhawk Drive Cedar City, Utah

Mini-Excavator Existing

East side of proposed building

Dixie NF 07/27/2010

Not Encountered

Ground Surface Top Soil: SM-ML (0 to 3") Silt, Clay, and Sand mixture, soft, major root zone, dry, light brown Sandy Gravel w/trace Silt: GP (3" to 8') fine to coarse sand, fine to coarse gravel, cobbles to 8" with some cobbles to 12", cobbles increase in size with depth, all gravel and cobbles rounded, dense, dry, brown excavation more difficult at 7'

End at required depth at 8'

3A

Project Name:

Location:

Excavation Method:

Elevation:

Remarks:

Project No.:

Forest:

Date Excavated:

Water Level:

FIGURE

US Forest Forest Service Region 4 324 25th Street Ogden, Utah 84401

G ra ph ic al L og

W at er L ev el

DESCRIPTION

D E

PT

H

F T

SA

M

PL

E

T Y

PE

SP

T

B L

O W

S/

FT

M O

IS

T

U R

E

P

A

SS

IN

G

D R

Y D

E N

SI

F)

L iq ui d

L im it

Pl as tic L im it

REMARKS

-2

Cedar City Maintenance Shop Kittyhawk Drive Cedar City, Utah

Mini-Excavator Existing

North side of proposed building

Dixie NF 07/27/2010

Not Encountered

Ground Surface Top Soil: SM-ML (0 to 12") Silty Clay and Sand mixture, soft, major root zone, dry, light brown

Sandy Gravel w/trace Silt: GP (12" to 6') fine to coarse sand, fine to coarse gravel, cobbles to 8" with occasional cobbles to 18", dense, moist, brown

Silty Clay w/trace Sand: CL (6' to 7') fine to medium sand, stiff, pinholes, moist, brown torevane TV=0.5 TSF Sandy Gravel with Trace Silt: GP (7' to 9') fine to coarse sand, fine to coarse gravel, cobbles to 18", dense, dry, brown

Bag testpit sidewall caving excavation more difficult at 7'

End at required depth 9'

3B

Project Name:

Location:

Excavation Method:

Elevation:

Remarks:

Project No.:

Forest:

Date Excavated:

Water Level:

FIGURE

US Forest Forest Service Region 4 324 25th Street Ogden, Utah 84401

G ra ph ic al L og

W at er L ev el

DESCRIPTION

D E

PT

H

F T

SA

M

PL

E

T Y

PE

SP

T

B L

O W

S/

FT

M O

IS

T

U R

E

P

A

SS

IN

G

D R

Y D

E N

SI

F)

L iq ui d

L im it

Pl as tic L im it

REMARKS

-3

Cedar City Maintenance Shop Kittyhawk Drive Cedar City, Utah

Mini-Excavator Existing

Southwest of proposed building, waterline trench area

Dixie NF 07/27/2010

Not Encountered

Ground Surface Sand and Silt SM-ML: (0 to 5') fine to medium sand, medium dense, moist, light brown

Sandy Gravel w/trace Silt: GP (5' to 7') fine to coarse sand, fine to coarse gravel, cobbles to 8" with occasional cobbles to 18", dense, moist, brown

Silty Clayw/some Sand: CL (7' to 7.5') medium stiff, brown observed as a pocket of soil on east side of testpit wall excavation Sandy Gravel with Trace Silt: GP (7.5' to 9') fine to coarse sand, fine to coarse gravel, cobbles to 18", dense, dry, brown

Bag

TW

3.5

NP

testpit sidewall caving

Undisturbed ThinWall sample taken excavation more difficult at 7'

End at required depth 9'

3C

100 200 400 800 1600

0.95

H ei gh t ( in ch es

REPORT OF CONSOLIDATION LAB TEST

Cedar City TP-3 @ 3 to 3.5'

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

Sample Type: Undisturbed, Trimmed Initial Dry Density (pcf): 89 Final Dry Density (pcf): 106 Initial Moisture Content (%): 3.5 Final Moisture Content (%): 22.5 Remarks: Saturated @ 1,600 psf, Collapse 9.7%

64001600400

0.8

0.85

0.9

100 1,000 10,000 100,000 Load (psf)

Laboratory Data

PARTIAL GRADATION WORKSHEET (No. 200 Wash)

CLIENT:

PROJECT: Kitty Hawk USFS

JOB NUMBER: 1010-002-10

BORING/TEST PIT: TP-3

DEPTH: 3

SAMPLE NUMBER: 2

SOIL DESCRIPTION: Silty Sand / Sandy Silt with some clay, slightly moist, orange brown

PAN LABEL 22A

PAN WEIGHT 16.15

WEIGHT BEFORE WASHING (WET SOIL + PAN) 220.43

WEIGHT BEFORE WASHING (DRY SOIL + PAN) 215.4

WEIGHT RETAINED AFTER WASHING (DRY SOIL + PAN) 120.33

MOISTURE CONTENT % 2.5

PERCENT RETAINED NO. 200 SIEVE 52.3

PERCENT PASSING NO. 200 SIEVE 47.7

SOIL CLASSIFICATION SM/ML