Clarks Creek Geo Rpt.pdf

REPORT OF GEOTECHNICAL EXPLORATION

Longarm Branch Culvert Replacement

Cherokee National Forest

Unicoi County, Tennessee

Prepared For:

USDA Forest Service

Prepared By:

AMEC Environment & Infrastructure, Inc.

July 30, 2012

Cherokee National Forest, Unicoi County, TN AMEC Project 6163120182, Phase 02

Page ii

TABLE OF CONTENTS

Page

LIST OF FIGURES ........................................................................................................... iii LIST OF APPENDICES .................................................................................................... iv EXECUTIVE SUMMARY ................................................................................................... v

1.0 INTRODUCTION

2.0 OBJECTIVES OF EXPLORATION

3.0 SCOPE OF EXPLORATION

4.0 PROJECT INFORMATION AND SITE CONDITIONS

5.0 SITE GEOLOGY

6.0 SUBSURFACE CONDITIONS

7.0 GROUND-WATER CONDITIONS

8.0 FOUNDATION RECOMMENDATIONS

9.0 EARTHWORK RECOMMENDATIONS

9.1 GENERAL SITE PREPARATION

9.2 EXCAVATION

9.3 GROUND WATER MANAGEMENT

9.4 PERMANENT SLOPE RECOMMENDATIONS

9.5 COMPACTED FILL

10.0 BASIS OF RECOMMENDATIONS

FIGURES

APPENDICES

Page iii

LIST OF FIGURES

Figure 1 Site Location Map

Figure 2 Boring Location Plan

Page iv

LIST OF APPENDICES

Appendix A Site Photographs

Appendix B Key to Symbols and Descriptions, Test Boring Records, Subsurface Fence

Diagram and Core Photographs

Page v

EXECUTIVE SUMMARY

AMEC was selected by the Forest Service to perform a geotechnical exploration for the Longarm Branch Culvert Replacement Project in the Cherokee National Forest along Clarks Creek Road in Unicoi County, Tennessee. The objectives of our exploration were to characterize subsurface conditions at the subject site and provide recommendations regarding foundation support and site preparation for the proposed project.

The Forest Service plans to replace the three existing corrugated metal culverts along Clarks Creek Road at the Longarm Branch Creek crossing. We understand it is proposed to replace the existing culverts with a bottomless aluminum box culvert.

The exploration consisted of drilling two borings to depths of about 26 to 27 feet (one boring on each side of the existing group of culverts). The borings were extended at least 15 feet into relatively sound bedrock prior to termination. Hollow-stem augers and NQ rock coring were used to advance the borings. Standard penetration testing was performed in the overburden soils in conjunction with the augering. Primary findings of our geotechnical exploration are summarized following:

· The borings typically encountered fill and alluvial soils overlying bedrock. Fill was encountered in Borings B-1 and B-2 to estimated depths of about 3 and 5 feet, respectively. The fill was generally composed of brown sandy silty clay/clayey silt with some gravel, cobbles and organics. Standard penetration test (SPT) N-values in the fill ranged from 10 to 21 blows per foot (bpf) indicating clayey soil consistencies ranging from stiff to very stiff and coarse-grained soil consistencies of firm. The fine grained fill in Boring B-1 was judged to have a firm consistency.

· Beneath the fill, alluvial soils and likely alluvial soils were encountered in Borings B-1 and B-2 to estimated depths of about

7.7 and 9.4 feet respectively. The alluvial soils were generally composed of silty sands, gravel, cobbles and boulders.

· Shale interbedded with shaly siltstone and fine sandstone underlies the overburden soils at the site. The shale is very weak to medium strong. As would be expected, the weaker more weathered shale was encountered near the bedrock surface. Several stained discontinuities were observed in the core. Bedding plane dips generally ranged from about 20 to 35 degrees. Core recoveries were generally good, except near the bedrock surface.

· Ground water was encountered at a depth of about 7 feet in Boring B-1 prior to backfilling. Ground water was not observed at the time of drilling prior to coring in Boring B-2. We anticipate ground-water levels will be mirror water levels in the adjacent stream.

· Given bedrock was exposed in portions of the stream bed and was encountered in the Borings B-1 and B-2 at estimated depths of

Page vi about 7.7 and 9.4 feet, respectively (just below the stream bed elevation), we recommend supporting the new structure on “shallow” spread and strip foundations bearing on the slightly weathered to fresh, moderately strong shale with interbedded shaly siltstone and fine sandstone bedrock underlying the site. The shale, siltstone and sandstone at and near the bedrock surface is variably weathered. The less weathered, moderately strong shale, siltstone and sandstone was encountered in the borings at depths below about 10 to 11 feet (an estimated 2 to 4 feet below the stream bed level).

· The foundations will bear below the stream bed level and dewatering of the foundation excavations will be required to construction the foundations. The stream or portions of the stream will likely require diverting and/or “pumping around” and foundation excavations may require protection with diversion/coffer dams. It is anticipated ground-water control can be provided using sumps and cutoff trenches outside the perimeters of foundation excavations.

We recommend the ground-water levels be lowered and maintained at a depth of at least one foot below foundation excavation bottoms during construction.

· We anticipate the fill and alluvial materials encountered in the borings can be excavated for the most part with conventional earthmoving equipment (i.e., backhoes, trackhoes, loaders, scrapers and dozers). Removing larger boulders may be facilitated by breaking boulders into smaller pieces using hydraulic and/or pneumatic hammers. The shale, siltstone and sandstone at and near the bedrock surface is variably weathered. We anticipate the more weathered rock encountered near the bedrock surface can be ripped using a larger trackhoe. The more competent shale, siltstone and sandstone will likely require the use of hydraulic and/or pneumatic hammers to facilitate excavation.

This summary is only an overview and should not be used as a separate document or in place of reading the entire report, including the appendices.

1.0 INTRODUCTION

This report presents the findings of our subsurface exploration recently performed for the Longarm Branch Culvert Replacement Project in the Cherokee National Forest in Unicoi County, Tennessee. Our services, as authorized through Contract Number AG-43ZP-C-12- 0005, Order AG-4756-D-0040, were provided in general accordance with our proposal for the Longarm Branch Culvert Replacement Geotechnical Exploration Rev. 1, dated May 24, 2012.

2.0 OBJECTIVES OF EXPLORATION

The objectives of our exploration were to characterize subsurface conditions at the subject site and provide recommendations regarding foundation support and site preparation for the subject project. An assessment of site environmental conditions or an assessment for the presence or absence of pollutants in the soil, bedrock, surface water, or ground water of the site was beyond the proposed objectives of our exploration.

3.0 SCOPE OF EXPLORATION

The scope of our exploration was based on our proposal, Longarm Branch Culvert Replacement Geotechnical Exploration Rev. 1, dated May 24, 2012. This geotechnical scope of work was generally based on a request for proposals from the Forest Service provided in an email dated May 23, 2012. The scope of the exploration for the project is summarized following:

· Drilling two test borings designated B-1 and B-2 to depth of about 26.3 and 26.8 feet respectively. The borings were extended at least 15 feet into relatively sound bedrock prior to termination. NQ coring techniques were used from the ground surface to boring termination in Boring B-1 because of the boulders and cobbles observed at that location. Boring B- 2 was augered to refusal (the point at which the soil drilling equipment could not effectively penetrate the material encountered) and then extended using NQ coring techniques to the termination depth.

· Standard penetration tests were performed in Boring B-2 prior to auger refusal.

· Ground water measurements at the time of drilling.

· Backfill of the soil test borings with a mix of auger cuttings and hole-plug (bentonite clay chips).

· Preparing this geotechnical report summarizing the exploration results and providing our recommendations regarding foundation support and site preparation for the subject project site.

The drilling and sampling were performed in general accordance with ASTM. The drilling was performed on July 13 and 16, 2012. The equipment used consisted of CME Model 55 track-mounted drill rig equipped with an automatic hammer. The borings were advanced in the overburden soils using hollow-stem augers (where practical) in general accordance with ASTM D 1452. Refusal materials were cored in general accordance with ASTM D 2113 using a NQ-size core barrel. Rock recovery and rock quality designation (RQD) were measured and recorded in general accordance with ASTM D 6032.

Standard penetration tests (SPTs) were generally conducted on about 2½-foot vertical intervals to the auger refusal depths. SPT was performed in general accordance with ASTM D 1586.

Ground-water levels were measured during drilling in each boring. Upon completion of drilling, the test borings were backfilled to the existing ground surface with a combination of auger cuttings and bentonite chips.

We had originally proposed to perform a limited laboratory testing program consisting of five moisture content tests, one Atterberg limits determination and one gain grain size analysis. We generally did not obtain soil samples suitable for testing. Therefore, no laboratory testing was performed.

Subsurface conditions encountered in the borings are presented on the Test Boring Records in Appendix B.

4.0 PROJECT INFORMATION AND SITE CONDITIONS

Project information was provided to us by Mr. Gary Hubbard, P.E., with the Forest Service in a Request for Proposals included in an email dated May 23, 2012. Subsequently, we were provided an existing topographic site of the project site. The Longarm Branch Creek crossing is located in the Cherokee National Forest along Clarks Creek Road at Mile Post (MP) 3.41 in Unicoi County, Tennessee. The latitude and longitude of the crossing are 36°7’33.82” North and 82°32’13.00” West. The general site location is shown on Figure 1. The topography in the project vicinity is mountainous.

The Forest Service plans to replace the three existing corrugated metal culverts along Clarks Creek Road at the Longarm Branch Creek crossing. The existing culverts appear to typically have an arch or elliptical shape with widths of about 7 feet and heights of 5 feet. We understand it is proposed to replace the existing culverts with a bottomless aluminum box culvert.

Clarks Creek Road typically follows Clarks Creek in a forested valley. Clarks Creek Road is gravel in the national forest. The Longarm Branch crossing is near where Longarm Branch Creek merges into Clarks Creek. The project area is wooded. The Longarm Branch Creek bed is about 20 to 30 feet wide in the general crossing area. The water flow generally did not cover the entire stream bed while we were on-site and was typically less than 1-foot deep. Materials exposed in the stream bed consisted of sand, gravel, cobbles, boulders and bedrock. Bedrock was observed in the stream bed at the culverts downstream outlet. Selected photographs of the site are provided in Appendix A.

5.0 SITE GEOLOGY

Bulletin 58, Tennessee Division of Geology (1958), shows the Erwin Formation underlies the project site. The bedrock of the Erwin Formation consists primarily of Quartzite , shale, siltstone and sandstone. The bedrock cored at the site consisted of shale interbedded/mixed with shaley siltstone and fine sandstone consistent with the Erwin Formation.

6.0 SUBSURFACE CONDITIONS

Subsurface conditions in the proposed project area were explored with two test borings designated B-1 and B-2 as previously noted. AMEC in conjunction with the Forest Service selected the test borings locations. The locations were established at accessible locations to the drill rig. The locations were established in the field by AMEC personnel by measuring distances from on-site landmarks. Ground surface elevations at the boring locations were obtained by plotting the boring locations on the existing topographic site plan of the site provided by the Forest Service. The boring locations and boring ground surface elevations are shown on the Boring Location Plan, Figure 2 and on the Test Boring Records in Appendix B, respectively, and should be considered approximate based on their method of establishment.

Subsurface conditions encountered at the boring locations are shown on the Test Boring Records. The Test Boring Records represent our interpretation of the subsurface conditions, based on the field logs and visual examination of the samples by one of our geologists and/or geotechnical engineers. The lines designating the interfaces between various strata on the Test Boring Records represent the approximate interface locations.

The borings typically encountered fill and alluvial soils overlying bedrock. Fill is material that has been transported to its current location by human activity. Alluvial soils are soils that have been transported to their present location by water. Brief descriptions of the materials encountered in the borings are provided in the following subsections. Detailed descriptions of the materials encountered in each boring are presented on the Test Boring Records.

Fill was encountered in Borings B-1 and B-2 to estimated depths of about 3 and 5 feet, respectively. The fill was generally composed of brown sandy silty clay/clayey silt with some gravel, cobbles and organics. Standard penetration test (SPT) N-values in the fill ranged from 10 to 21 blows per foot (bpf) indicating clayey soil consistencies ranging from stiff to very stiff and coarse-grained soil consistencies of firm. The fine grained fill in Boring B-1 was judged to have a firm consistency.

Beneath the fill, alluvial soils and likely alluvial soils were encountered in Borings B-1 and B-2 to estimated depths of about 7.7 and 9.4 feet respectively. The alluvial soils were generally composed of silty sands, gravel, cobbles and boulders. Selected photographs of the alluvium in the stream banks are provided in Appendix A.

Shale interbedded with shaly siltstone and fine sandstone underlies the overburden soils at the site. The shale is very weak to medium strong. As would be expected, the weaker more weathered shale was encountered near the bedrock surface. The color of the fresh shale is dark gray, while the shaly siltstone and fine sandstone is a lighter gray. Weathering alters the color to lighter gray-browns and browns. Several stained discontinuities were observed in the core.

Bedding plane dips generally ranged from about 20 to 35 degrees. Core recoveries were generally good, except near the bedrock surface. The core recoveries and RQD values for each individual core run are shown on the respective Test Boring Records in Appendix B.

Photographs of core recovered are also provided in Appendix B.

7.0 GROUND-WATER CONDITIONS

Ground water was encountered at a depth of about 7 feet in Boring B-1 prior to backfilling.

Ground water was not observed at the time of drilling prior to coring in Boring B-2. For safety reasons, the borings were backfilled promptly; consequently, long-term measurements for the presence or absence of ground water were not obtained.

Fluctuations in the ground-water level occur because of variation in rainfall, evaporation, construction activity, surface run-off, and other site-specific factors such as fluctuation of water levels in the stream. We anticipate ground-water levels will be mirror water levels in the stream.

8.0 FOUNDATION RECOMMENDATIONS

Given bedrock was exposed in portions of the stream bed and was encountered in the Borings B-1 and B-2 at estimated depths of about 7.7 and 9.4 feet, respectively (just below the stream bed elevation), we recommend supporting the new structure on “shallow” spread and strip foundations bearing on the slightly weathered to fresh, moderately strong shale with interbedded shaly siltstone and fine sandstone bedrock underlying the site. The shale, siltstone and sandstone at and near the bedrock surface is variably weathered. The less weathered, moderately strong shale, siltstone and sandstone was encountered in the borings at depths below about 10 to 11 feet (an estimated 2 to 4 feet below the stream bed level). Strip and spread foundations bearing on the moderately strong shale, siltstone and sandstone bedrock may be sized for a maximum allowable bearing pressure of 10 kips per square foot (ksf). We recommend an un-factored, ultimate coefficient of friction between the clean moderately hard shale/siltstone/sandstone and concrete of 0.5 for resistance of footing lateral loads. We expect total and differential settlements will be well under 1 inch and ¾ of an inch, respectively, for the anticipated loading and foundation conditions.

As noted above, the bedrock surface is variably weathered. Residual soils, and decomposed and severely weathered rock exposed in foundations excavations will require removal/undercutting to expose less weathered more competent rock. On uneven rock bearing surfaces, a leveling course of concrete may be required.

The foundations will bear below the stream bed level and dewatering of the foundation excavations will be required to construction the foundations. The stream or portions of the stream will likely require diverting and foundation excavations may require protection with coffer dams. Excavation side slopes will need to be sloped/cut-back or shored in accordance with OSHA requirements. These items are discussed further in the Earthworks Section of this report.

Foundation bearing areas should be level or suitably benched, and free of loose soil and debris.

We recommend a qualified geotechnical engineer observe the foundation excavations and drilling of probe holes (as discussed following) prior to placing reinforcing steel to verify foundation bearing materials are suitable for the design bearing pressure. We recommend the contractor drill probe holes on about 15-foot centers along the length of the foundations. The probe holes should be at least 1.5 inches in diameter. The probe holes should be drilled to a depth of 1.5 times the foundation width or ten feet, whichever is less. The holes should be checked by a qualified geotechnical engineer with a feeler rod to assess the rock continuity.

Compressible seams and severely weathered and decomposed zones may require remedial action depending on their location and extent. Additional probe holes may be required by the geotechnical engineer to check suspect areas.

9.0 EARTHWORK RECOMMENDATIONS

Following are general earthwork considerations and recommendations.

9.1 GENERAL SITE PREPARATION

We understand the existing culverts will be demolished/removed prior to the installation of the new structure. Excavations created below subgrade levels during the demolition should be backfilled with compacted soil or aggregate fill placed in accordance with the recommendations of this report.

We recommend proofrolling subgrades for roadways and areas to receive compacted fill (if practical) as discussed below to identify soft subgrade areas. Any topsoil, vegetation, debris, and surface soil containing organic material should be stripped from construction areas and disposed of properly. After demolition and any stripping, and after proposed grades are achieved in cut areas, exposed subgrades should be proofrolled where practical.

Proofrolling should be done after a suitable period of dry weather to avoid degrading an otherwise acceptable subgrade. Proofrolling should be performed with a heavily loaded dump truck or with similar approved construction equipment. The proofrolling equipment should make at least four passes over each section, with the last two passes perpendicular to the first two where practical.

We recommend exposed subgrades and proofrolling operations be observed and documented by qualified geotechnical personnel. We recommend actual subgrade stabilization requirements, if deemed necessary, be determined at the time of site preparation, based on observations of the subgrade and the stability of the subgrades as determined during proofrolling or other methods determined at time of construction. Soft, organic, highly plastic, excessively wet soils that pump, rut, or wave during site grading or proofrolling operations should be removed or stabilized.

If soft soils are encountered in roadway areas, they are typically mitigated by undercutting the soft soils to expose competent soils and then backfilling with compacted fill to plan subgrade levels or by undercutting poor subgrade soils to some depth and then placing a high-modulus geotextile, geogrid and/or layer of aggregate to establish a stable platform upon which to backfill with compacted fill.

During the excavation and grading, positive surface drainage should be maintained to prevent the accumulation of water. Pumping from sumps may be required in undercut excavations. If the exposed subgrade becomes excessively wet or frozen, or if conditions different from those described previously in this report are encountered, a qualified geotechnical engineer should be consulted. Wet weather, freeze/thaw, and construction activity can all contribute to subgrade degradation. The contractor should perform final subgrade preparations shortly before roadways are to be constructed.

The fine-grained soils encountered near the ground surface in the borings will not support construction traffic as they get wet. Therefore, the contractor should anticipate additional subgrade stabilization will be required during and shortly after wet periods to repair fine-grained soil subgrade areas damaged by construction traffic.

9.2 EXCAVATION

9.1.1 Excavation/Difficult Excavation

We anticipate the fill and alluvial materials encountered in the borings can be excavated for the most part with conventional earthmoving equipment (i.e., backhoes, trackhoes, loaders, scrapers and dozers). Removing larger boulders may be facilitated by breaking boulders into smaller pieces using hydraulic and/or pneumatic hammers.

The shale, siltstone and sandstone at and near the bedrock surface is variably weathered. We anticipate the more weathered rock encountered near the bedrock surface can be ripped using a larger trackhoe. The more competent shale, siltstone and sandstone will likely require the use of hydraulic and/or pneumatic hammers to facilitate excavation.

9.2.2 Construction Slopes and Temporary Excavation Support

Temporary excavations should be constructed (sloped or shored) in accordance with OSHA requirements. The alluvial soils underlying the site are generally sands and gravels. In addition, foundation excavations will extend below the stream and ground-water levels. We classify the soils in the borings as “C” soils in accordance with OSHA. Where it is desired to not slope back excavation sides, temporary shoring will be required to protect excavations. Again, shoring should be constructed in accordance with OSHA requirements.

9.3 GROUND WATER MANAGEMENT

The foundations will bear below the stream bed level and dewatering of the foundation excavations will be required to construct the foundations. The stream or portions of the stream will likely require diverting and/or “pumping around” and foundation excavations may require protection with diversion/coffer dams.

It is anticipated ground-water control can be provided using sumps and cutoff trenches outside the perimeters of foundation excavations. We recommend the ground-water levels be lowered and maintained at a depth of at least one foot below foundation excavation bottoms during construction.

9.4 PERMANENT SLOPE RECOMMENDATIONS

We do not anticipate the project will include any new significant slopes. We generally recommend permanent slopes less than 20 feet high in competent residual and alluvial soils or properly compacted fill placed in accordance with our recommendations be constructed at 2.5H:1V or flatter. We recommend higher or steeper slopes and slopes where structures will be located adjacent to the crest or toe be evaluated further with the necessary additional exploration and testing as required.

Permanent cut and fill slopes should be seeded and mulched or receive a surface revetment such as riprap to prevent erosion. Surface drainage ditches or swales should be constructed at the crests and toes of the slopes to control surface water.

9.5 COMPACTED FILL

Backfill for the culvert/structure should be in accordance with the manufacturer’s recommendations. Our general compacted fill recommendations follow.

Fill soils should be compacted in loose lifts not more than 8 inches thick to at least 98 percent of the standard Proctor maximum dry density (ASTM D 698). The upper 24 inches of fill beneath roadways should be compacted to at least 100 percent of standard Proctor maximum dry density.

As a general rule the moisture content should be maintained within +2 to -3 percentage points of the optimum standard Proctor moisture content. The actual soil used in the compacted fill may dictate narrower or broader required moisture content limits to achieve required compaction levels. This may require contractors to dry or wet soils prior to placement.

Where subgrades are below ground-water levels or are wet and free water is present, an interval of compacted clean-graded stone will need to be placed to a point above water levels to allow placement of the compacted soil fill in the “dry”. A filter/separation fabric should be placed on the clean-graded stone prior to placing soil fill.

We recommend fill soils have a plasticity index (PI) of 30 or less and a standard Proctor maximum dry density of no less than 90 pounds per cubic foot (pcf). Fill soils should also be free of organics, debris and deleterious materials and fragment sizes with dimensions greater than 5 inches. The on-site soils minus larger cobbles and the boulders appear suitable for reuse as compacted fill with proper moisture conditioning.

Well before filling operations are scheduled to begin, the proposed fill soil should be tested to determine if the proposed soil is acceptable and for quality control during fill placement. Testing should include maximum dry density, optimum moisture content, natural moisture content, plasticity and grain size distribution.

If surface soils become excessively wet or frozen, fill operations should be halted and we should be consulted for guidance. A qualified engineering technician should observe fill placement and verify specified compaction levels are achieved through field density testing. The frequency of in-place density testing during fill placement will depend on the configuration of the project and volume of fill being placed.

10.0 BASIS OF RECOMMENDATIONS

The recommendations provided herein are based on the subsurface conditions and on project information provided to us; they apply only to the specific project and site discussed in this report. If the project information section in this report contains incorrect information or if additional information becomes available, you should convey the corrected or additional information to us and retain us to review our recommendations. We will then modify them if the new information has rendered them inappropriate for the proposed project.

Regardless of the thoroughness of a field exploration, there is always a possibility that conditions between boring locations will differ from those at specific boring locations, and that conditions will not be as anticipated by the designers or contractors. In addition, the construction process may itself alter subsurface conditions. Therefore, experienced geotechnical personnel should observe and document the construction procedures used and the conditions encountered. Unanticipated conditions and inappropriate procedures will be reported to the design team, along with recommendations to solve the problems created. We recommend AMEC be retained to provide this service, based upon our familiarity with the subsurface conditions and the intent of the recommendations.

Our exploration services include storing the collected samples and making them available for inspection for a period of 30 days. The samples are then discarded unless you request otherwise.

FIGURES

APPENDIX A

SITE PHOTOGRAPHS

Photograph 1- Project site looking generally northeast down Clarks Creek Road.

Photograph 2 – Longarm Branch looking upstream.

Photograph 3 – Longarm Branch looking downstream.

Photograph 4 – Looking at existing culverts from upstream.

Photograph 5 – Bedrock exposed in stream bed upstream of culverts.

Photograph 6 – Downstream ends of culverts.

Photograph 7 – Bedrock exposed in stream bed and cobbles in bank.

Photograph 8 – Silt, sand, gravel, cobbles and boulders in stream bank.

APPENDIX B

KEY TO SYMBOLS AND DESCRIPTIONS

TEST BORING RECORDS

SUBSURFACE FENCE DIAGRAM

CORE PHOTOGRAPHS

Stiff

Medium

3/4"

Coarse

SANDSTONE

SHALE

RESIDUUM - Stiff to very hard

RESIDUUM - Soft to firm

Cobbles

CONCRETE

No.40

Very Dense

No.10 No.4

Water Table at time of drilling

Very Hard

21 - 30

Firm

12"

Split Spoon Sample

Loose

No. of BlowsRelative Density

5 - 10

Fine

Consistency

Fine

SUBSOIL

3"

ALLUVIUM

COLLUVIUM

LIMESTONE

0 - 4

5 - 8

No Sample

Rotary Drill

AUGER BORING

BOUNDARY CLASSIFICATIONS: Soils possessing characteristics of two groups are designated by combinations of group symbols.

Crandall Sampler

Pressure Meter

9 - 15

SILTSTONE

Correlation of Penetration Resistance with Relative Density and Consistency

SILT & CLAY

31 - 50

16 - 30

Very Soft

Soft

Firm

Auger Cuttings

Dilatometer

No Recovery

Water Table after 24 hours

Rock Core 60-100 = RQD / Recovery

SAND & GRAVEL

No. of Blows

Hard

No.200

Coarse

SILT OR CLAY

SAND

Very Firm

TYPICAL NAMES

COAL

AMEC Environment & Infrastructure, Inc.

9725 Cogdill Road

Knoxville, Tennessee 37931 865-671-6774 Fax: 865-671-6254

31 - 50

Over 50

Very Loose

UNDISTURBED SAMPLE ATTEMPT

Reference: The Unified Soil Classification System, Corps of Engineers, U.S. Army Technical Memorandum No. 3-357, Vol. 1, March, 1953 (Revised April, 1960)

0 - 2

3 - 4

Very Stiff

Over 50

Boulders

U.S. STANDARD SIEVE SIZE

GRAVEL

11 - 20

GROUP

SYMBOLS

TYPICAL NAMES

GROUP

SYMBOLS

Dense

Undisturbed Sample 1.5-2.0 = Recovered (ft) / Pushed (ft)

DOLOMITE

TOPSOIL

ASPHALT

FILL

KEY TO SYMBOLS AND

DESCRIPTIONS

SHALE/SILTSTONE - Shale interbedded with shaly siltstone and fine sandstone

FIRM, BROWN, SILTY CLAY WITH SAND AND

GRAVEL AND SOME ORGANICS - FILL

NOTE: STARTED NQ CORING FROM GROUND

SURFACE AS BOULDERS AND COBBLES OBSERVED

NEAR BORING LOCATION

SILTY SAND AND GRAVEL WITH COBBLES AND

BOULDERS - LIKELY ALLUVIUM

SHALE INTERBEDDED WITH SHALY SILTSTONE AND

FINE SANDSTONE. LIGHT GRAY, GRAY-BROWN, AND

BROWN. WEAK WITH LITTLE MODERATE. STRONG

FINE SANDSTONE. HIGHLY TO MODERATELY

WEATHERED.

NOTE: SIGNIFICANT CORE LOSS IN THIS INTERVAL.

SHALE INTERBEDDED WITH SHALY SILTSTONE AND

FINE SANDSTONE. DARK GRAY, GRAY-BROWN, AND

LIGHT GRAY. MODERATELY STRONG. MODERATELY

WEATHERED TO FRESH. FRACTURED.

SHALE INTERBEDDED WITH SHALY SILTSTONE AND

FINE SANDSTONE. DARK GRAY TO LIGHT GRAY.

MODERATELY STRONG. SLIGHTLY WEATHERED TO

FRESH.

NOTE: STAINED DISCONTINUITIES AT DEPTHS OF

ABOUT 11.9', 12.3' TO 12.5, 12.8' AND 14.2'. FRACTURE

ZONES FROM DEPTHS OF ABOUT 15.9' TO 16.6' AND

18.5' TO 18.8'. STAINED DISCONTINUITIES AT DEPTHS

OF ABOUT 21.2' TO 21.3' FRACTURE ZONE FROM

DEPTH OF ABOUT 25.2' TO 25.6'

CORING TERMINATED AT 26.3'

0-46

68-96

77-92

92-98

RC-1

RC-2

RC-3

RC-4

RC-5

REMARKS:

SEE KEY SYMBOL SHEET FOR EXPLANATION OF

SYMBOLS AND ABBREVIATIONS BELOW.

st n d rd

SOIL TEST BORING RECORD

FINES (%)

SPT (bpf)

T Y P E

97.5

92.5

87.5

82.5

77.5

72.5

67.5

62.5

57.5

52.5 0 10 20 30 40 50 60 70 80 90 100

DRILLED:

I D E N T

SAMPLESE

L E V

(ft)

SOIL CLASSIFICATION

AND REMARKS

10 20 30 40 50 60 70 80 90 100

PL (%) NM (%) LL (%)

N-COUNT

L E G E N D

STANDARD PENETRATION RESISTANCE TESTING

PERFORMED USING AN AUTOMATIC HAMMER.

BORING NO.: B-1

D E P T H

(ft)

THIS RECORD IS A REASONABLE INTERPRETATION OF

SUBSURFACE CONDITIONS AT THE EXPLORATION

LOCATION. SUBSURFACE CONDITIONS AT OTHER

LOCATIONS AND AT OTHER TIMES MAY DIFFER.

INTERFACES BEWEEN STRATA ARE APPROXIMATE.

TRANSITIONS BETWEEN STRATA MAY BE GRADUAL.

PROJECT:

PROJ. NO.:

Driller :

Logged By: JCM

Checked By: TL

Longarm Branch Culvert Replacement

July 13, 2012

6163-12-0182.02

S O

IL

.G

P J

L A

W G

IB

B

.G D

T

/3

/1

STIFF TO VERY STIFF, BROWN, SANDY SILTY CLAY /

CLAYEY SILT WITH GRAVEL AND SOME COBBLES -

FILL

FIRM, BROWN, SILTY SAND WITH GRAVEL - FILL

AUGER REFUSAL AT 5.0'

BEGAN NQ CORING AT 5.0'

SILTY SAND, GRAVEL, COBBLE, AND BOULDERS -

ALLUVIUM

SHALE INTERBEDDED WITH SHALY SILTSTONE AND

FINE SANDSTONE. LIGHT BROWN, BROWN, LIGHT

GRAY, AND GRAY. VERY WEAK TO MODERATELY

STRONG. HIGHLY TO SLIGHTLY WEATHERED.

NOTE: LARGE CORE LOSS IN THIS INTERVAL

SHALE INTERBEDDED WITH SHALY SILTSTONE AND

FINE SANDSTONE. DARK GRAY TO LIGHT GRAY.

MODERATELY STRONG. SLIGHTLY WEATHERED TO

FRESH.

NOTE: STRAINED FRACTURE ZONES FROM DEPTHS

OF ABOUT 17.1' TO 17.2', 23.0' TO 23.8', 24.4' TO 24.6',

AND 25.0' TO 25.1'. STRAINED FRACTURE AT DEPTH

OF ABOUT 26.6'

CORING TERMINATED AT 26.8'

5-5-5

5-4-17

16-8-9

0-40

62-82

93-98

70-100

SPT-1

SPT-2

SPT-3

RC-1

RC-2

RC-3

RC-4

RC-5

REMARKS:

SEE KEY SYMBOL SHEET FOR EXPLANATION OF

SYMBOLS AND ABBREVIATIONS BELOW.

st n d rd

SOIL TEST BORING RECORD

FINES (%)

SPT (bpf)

T Y P E

97.5

92.5

87.5

82.5

77.5

72.5

67.5

62.5

57.5

52.5 0 10 20 30 40 50 60 70 80 90 100

DRILLED:

I D E N T

SAMPLESE

L E V

(ft)

SOIL CLASSIFICATION

AND REMARKS

10 20 30 40 50 60 70 80 90 100

PL (%) NM (%) LL (%)

N-COUNT

L E G E N D

STANDARD PENETRATION RESISTANCE TESTING

PERFORMED USING AN AUTOMATIC HAMMER.

BORING NO.: B-2

D E P T H

(ft)

THIS RECORD IS A REASONABLE INTERPRETATION OF

SUBSURFACE CONDITIONS AT THE EXPLORATION

LOCATION. SUBSURFACE CONDITIONS AT OTHER

LOCATIONS AND AT OTHER TIMES MAY DIFFER.

INTERFACES BEWEEN STRATA ARE APPROXIMATE.

TRANSITIONS BETWEEN STRATA MAY BE GRADUAL.

PROJECT:

PROJ. NO.:

Driller :

Logged By: JCM

Checked By: TL

Longarm Branch Culvert Replacement

July 16, 2012

6163-12-0182.02

S O

IL

.G

P J

L A

W G

IB

B

.G

0 5 10 15 20 25 30 35 40 45 50 55 60

0 5 10 15 20 25 30 35 40 45 50 55 60

0-46

68-96

77-92

92-98

B-1 5-5-5

5-4-17

16-8-9

0-40

62-82

93-98

70-100

B-2

Borehole North

Position

Left, Front

Right, Front

Left, Back

Right, Back

DISTANCES:

Beginning

Ending

VIEWING ANGLES (degrees):

Horizontal

Vertical

Distance Along Baseline

DATE PLATE

East Elev.

97.5

97.5

East

10075

10127

10075

10127 6163-12-0182.02

26.3

26.8

PROJECT #

North

Longarm Branch Culvert Replacement

SUBSURFACE FENCE DIAGRAM A - A'

E le v a ti o n

Depth

B-1

B-2

10124

10075

Jul 12

0.0

0.0

SEE KEY SYMBOL SHEET FOR EXPLANATION

OF SYMBOLS AND ABBREVIATIONS

S E

C T

IO

N

.G

P J

F A

G W

G N

.G

10.0 BASIS OF RECOMMENDATIONS