Geotechnical Investigation - Cougar Tower - Lincoln Cty OR.PDF

Geotechnical Investigation Engineering Report

Cougar Tower

Lincoln County, Oregon Attachment 5

8/24/2012 jgbailey TextBox Attachment 5

TABLE OF CONTENTS

EXECUTIVE SUMMARY

1.0 INTRODUCTION

2.0 PROJECT INFORMATION

Page

APPENDIX A — FIELD EXPLORATION

APPENDIX B — LABORATORY TESTING

Exhibit B-1 Laboratory Testing

APPENDIX C — SUPPORTING DOCUMENTS

Geotechnical Engineering Report Proposed Communications Tower Lincoln County, Oregon

EXECUTIVE SUMMARY

0111111performed a geotechnical exploration for the proposed communications tower located near the coordinate of N45° 57' 19", W123° 51' 48" in Lincoln County, Oregon. IPS geotechnical scope of work included the advancement of one test boring near the proposed tower location to a depth of approximately 19 feet below existing site grades.

41 Based on the information obtained from our subsurface exploration, the site is suitable for development of the proposed project from a geotechnical perspective.

The site surface soils generally consisted of very stiff gravelly silt underlain by dense gravel and andesite bedrock. Groundwater was not encountered in the test boring at the time of drilling.

The proposed 80-foot self-support tower may be supported by a reinforced concrete mat foundation at the tower base bearing directly on the andesite bedrock.

This geotechnical executive summary should be used in conjunction with the entire report for design and/or construction purposes. It should be recognized that specific details were not included or fully developed in this section, and the report must be read in its entirety for a comprehensive understanding of the items contained herein. The section titled General Comments should be read for an understanding of the report limitations.

GEOTECHNICAL ENGINEERING REPORT

PROPOSED COMMUNICATIONS TOWER

N45° 57' 19", W123° 51' 48"

LINCOLN COUNTY, OREGON

1.0 INTRODUCTION

This report presents the results of our geotechnical engineering services performed for the proposed communications tower to be located near the coordinate of N45° 57 19", W123° 51 1 48" in Lincoln County, Oregon. Our geotechnical engineering scope of work for this project included the advancement of one test boring near the proposed tower location to a depth of approximately 19 feet below existing site grades. The results of our subsurface exploration were used to address the following elements of this project:

subsurface soil conditions •

• earthwork ra seismic considerations groundwater conditions 2, foundation design and construction

The boring log, along with a Boring Location Diagram (Exhibit A-1), are included in Appendix A of this report. A description of the field exploration is included in the appendix.

2.0 PROJECT INFORMATION

2.1 Project Description

ITEM DESCRIPTION

Site layout

Vertical: 62 kips

Shear: 43 kips (Maximum due to wind loading)

Moment: 5,700 kip-ft (Maximum due to wind loading)

Note: Several assumptions were made for the purposes of this repo& and are listed above.. These assumptions were necessary where specific project information was not provided to us- These assumptions should be verified by the owner and/or designers and any deviations from these assumptions should be brought to our attention. •

Base Tower Loads (Assumed maximum loads)

Proposed communications tower If Lincoln County, Oregon

2.2 Site Location and Description

DESCRIPTION

• - N45° 5719", W123° 51' 48" in Lincoln County, Oregon (See I Exhibit A-1) —

520, T 3$, R 22E Generally undeveloped forest with under-brush with the exception or an existing tower and equipment.buliding.

North: Existing tower and equipment building West: Forest land, undeveloped South: Forest land, undeveloped East: Forest land, undeveloped — – Grass and abundant under-brush and medium sized coniferous trees. ...•.

The site vicinity is relatively flat and sits near the top of small knoll Sloping down in all directions. The slopes are located over 100 feet from the base of the proposed structure. The lease area is at an approximate elevation of 1850 feet.

ITEM

Location

Section, Township, Range

, Existing site features

Surrounding developments

Current ground cover

Existing topography

3.0 SUBSURFACE CONDITIONS

3.1 Site Geology

We reviewed the regional geology of the general project site area as presented on the Environmental geology of Lincoln County, Oregon', Oregon Department of Geology and Mineral Industries, 1982, The area is mapped as Camptonite and related alkali intrusive rocks (Tic).

Camptonite occurs as glassy to tine-grained locally porphyntic intrusive rock and locally as zeolite-cemented tuff breccias.

Gravelly silt, trace sand and organics i Gravel, with silt and sand

VA

Geotechnical Engineering Report Proposed communications tower a Lincoln County, Oregon

3.2 Typical Subsurface Profile

Based on the results Of the boring, subsurface conditions on the project site can be generalized as follows:

I Approximate Depth to i Description i Bottom of Stratum Material Encountered Consistency/Density

I (feet) , _

, STRATUM 1

(Gravelly Silt) Gravel

Porphyritic Andesite

191 Porphyritic Andesite

1.. Actual bottom of stratum is undetermin- ed. The boring was terminated within this stratum at a depth of approximately 19 feet bgs.

2 The andesite was observed to be slightly to moderately . weathered with a very close to close joint pattern.

Conditions encountered at the boring location are indicated on the individual boring log found in Appendix A of this report. Stratification boundaries on the boring log represent the approximate location of changes in material tyries; in-situ, the transition between materials may be gradual.

Although the mapped geology identified the rock as intrusive, our exploration encountered an extrusive igneous rock (i.e., andesite). The porphyritic texture with both coarse and fine mineral grains indicates a complex cooling process involving both deep and near-surface 'crystal formation.

3.3 Groundwater

The boring was monitored during drilling for the pretence and level of groundwater. At the time of our field explorations, groundwater was not encountered in the boring while drilling. The boring extended into the bedrock by coring methods, and for this drilling method, water is circulated in the borehole. Therefore, the actual groundwater level at the site, if present, was not apparent after drilling, since the water pumped into the borehole precludes observing the natural groundwater level, if present. We would expect possible perched groundwater following extended wet periods and/or during spring thaw season to be encountered just above the interface with the andesite bedrock.

Long term monitoring in cased holes or piezometers would be required for an accurate evaluation of the groundivater conditions of the site soils/bedrock. Fluctuations of the groundwater level can occur due to seasonal variations in the amount of rainfall, runoff and

Very Stiff

D- ense

Medium hard2

Proposed communications tower Lincoln County, Oregon other factors not evident at the time the boring was performed. Evaluation of these factors is ' beyond the scope of this report.

3.4 Field Resistivity Testing

Field measurements of soil resistance using the Wenner Four-Electrode Method were performed in general accordance with ASTM: G 57. A series of soil resistance measurements were performed near the propoSed lease area along a single N-S oriented line. The soil resistance measurements were performed using a meter manufactured by Nilssen (Model 4D0).

The Wenner arrangement (equal electrode spacing) was used with the "a" spacing incrementally increasing from 2 to 40 feet. Results of the soil resistance measurements and

.calculatectresistivity are presented in the table below. Interpretation of the data from this survey was not included in the requested scope of services for this- project.

iSET :

i i--

Rx383 lyx957.5

10 FT_ .

Rx1915

Spacing. _. _.., 15 rr

Rx2872.6

I

40 ET

I Rx7660

Value

Formula p =

Measured

_2 FT l

Resistancei 770 650 ii 390 280 I 210 I 150 110

(OHMS)

Calculated i I

Resistivity 'p' 300,000 I 620,000 750,000 800,000 1 800,000 860,000 840,000

(OHM-CM) 1

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION

4.1 Geotechnical Considerations

Based on the subsurface conditions encountered in the boring, we recommend the proposed self-support tower be supported by a reinforced concrete mat foundation bearing directly on the andesite bedrock. The mat foundation should extend to the bedrock encountered below 4 feet at the boring location. Typically, these foundations extend about 5 feet below the ground surface. Therefore, the contractor should be prepared for difficult bedrock excavation at the foundation location.

Geotechnical engineering recommendations for foundation systems and other earth connected phases of the project are outlined below. The recommendations contained in this report are based upon the results of the field exploration, engineering analyses, and our current understanding of the proposed project..

Geotechnical Engineering Report • Proposed communications tower Lincoln County, Oregon

4.2 Earthwork

The following presents recommendations for site preparation, excavation, subgrade preparation and placement of engineered fills on the project The recommendations presented for design and construction of earth supported elements including foundations are contingent upon following the recommendations outlined in this section.

Site preparation should begin by stripping surface vegetation, organic-laden soils, debris, and other deleterious material within proposed construction areas. Approximately PA feet of silt overburden soil and 2% feet of gravel were located above the andesite at the exploration location and the thickness will likely vary over the tower location base. Undocumented fill, debris or deleterious materials were not encountered at the boring location. Actual stripping removal depths may be more or less than that observed at the exploration location. We recommend that a all.11.11111111.1 aid in evaluating that unsuitable materials are removed at the time of construction.

4.2.1 Bedrock Excavation

Bedrock material was encountered at about 4 feet bgs in the exploration. The Rock Quality Designation (ROD) values of the recovered rock cores ranged from 23 to 44 percent, which is indicative of rock quality varying from very poor to poor. We estimate that seismic (average shear and compression) wave velocities for the bedrock within the upper 10 feet could range from 1,000 feet per second to about 4,000 feet per second. Based on these estimated velocities and based on empirical Caterpillar performance charts, we estimate that the bedrock is within the rippable range for typical Caterpillar ripping equipment.

In our opinion, poor quality and/or closely jointed rock could be excavated using rock construction equipment that is equipped with rock teeth, rippers, and/or breakers. The contractor should be prepared to utilize hydraulic or pneumatic breakers, or blasting, to assist in bedrock removal. It should be noted that rock excavation and ripping is dependent on operator skill and experience. Rippabifity of rock is also dependent on rock conditions that will be encountered during construction and details of methods used to rip. These methods include, but are not limited to, cross-ripping techniques, number of shanks, tooth angle, and tooth penetration.

Over-breakage of bedrock in foundation and utility excavations should be anticipated, and will result in additional quantities of concrete or backfill material. Disturbed or blasted material below design grades must be removed and replaced with concrete (foundation) or compacted fill (utilities).

Proposed communications tower a Lincoln County, Oregon

Work area space constrictions can have an impact on the ability to rip bedrock. The communications tower foundation excavations will be relatively confined. This factor should be considered by the contractor when selecting bedrock excavation methods.

4.2.2 Fill Material Types

The suitability of soils used for structural fill depends primarily on the gradation and moisture content of the soil when it is placed. As the fines content (that portion passing the U.S. No. 200 sieve) of a soil increases it becomes increasingly sensitive to small changes in moisture content and adequate compaction becomes more difficult or impossible to achieve. Soils containing more than about 5 percent . fines by weight, such as the native soils, cannot be consistently compacted to the recommended degree when the moisture content is more than about 2 percent above or below optimum, Engineered or structural fill should meet the following material property requirements:

Fill Type'

Common Fill

Select Fill

Specification

Oregon Standard Specification for Construction(OSSC) 00330.13

Selected General Backfill

()SSC 00330.14 Selected Granular BackfiII with exception of no more

Acceptable for Placement

All locations across the site with the exception of underneath the footing, Recommended for dry weather only.

All locations across the site with the exception of underneath the footing, than 5% passing the No. 200 sieve by Wet Weather and Dry Weather acceptable.weight

• OSSC 02630.10 Dense Graded for leveling course underneath footings.

Wet Weather and Dry Weather acceptable.

1 Controlled, compacted fill should consist of approved Materials that are free (free ,--- less than 3% by weight) of organic matter and debris (e.g., wood sticks greater than %-inch, in diameter). Frozen material should not be used, and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted tote geotechnical engineer for evaluation.

4.2.3 Compaction Requirements

The following compaction requirements are recommended for the prepared subgrade and structural fill expected to be placed for this site:

Crushed Rock Base Course

(CRBC) Aggregate (2%0 to3/1-0

All locations across the site. Recommended

Proposed communications tower • Lincoln County, Oregonsiaturnmesena

Item Description 10-inches Or less in loose thickness when heavy, compaction equipment isFill Lift Thickness used.

95% of the material's modified Proctor maximum dry density (ASTM 01557) for Compaction areas underneath structures and gravel access drives.

Requirements'

90% of the material's modified Proctor maximum dry density (ASTM 01557) for all other areas.

4.2.4 Grading and Drainage

Positive drainage should be provided during construction and maintained throughout the life of the development Infiltration of water into trenches or foundation excavations should be prevented during construction. Backfill around the tower foundation base should be well compacted and free of all construction debris to reduce the possibility of moisture infiltration.

We recommend that the surface of the soils around the base of the tower be compacted and sloped to drain a minimum of 4 percent away from the base of the tower.

4.2.5 Construction Considerations

The near surface native soils encountered in the boring for this project consist of silty materials with an estimated moisture condition greater than about 2% over the material's estimated optimum moisture content. Therefore, it is likely that over-optimum soils will be encountered during construction and in order to reuse soils that are wet of the optimum moisture content; the soils will need to be dried by aeration during dry weather conditions. In addition, in order to protect the subgrades from disturbance, a rock protective mat may be required during wet weather. Otherwise, the subgrades could become disturbed from additional moisture (wet weather) or construction traffic and would be rendered unsuitable.

Construction traffic over the completed suhgrade should he avoided to the extent practicaL The site should also be graded to prevent ponding of surface water on the prepared subgrades or in excavations. If the subgrade should become frozen, desiccated, saturated, or disturbed, the affected material should be removed or these materials should be scarified, moisture conditioned, and recompacted.

The contractor is responsible for designing and constructing stable, temporary excavations (including utility trenches) as required for maintaining stability of both the excavation sides and bottoming. Excavations should be striped or shored in the interest of safety following local and federal regulations, including current OSHA excavation and trench safety standards.

Moisture Content' Within ±2 percent of optimum moisture content as determined by ASTM D1557.

1. We recommend that fill be tested for moisture content and compaction during placement. Should the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved.

UM'Geotechnical Engineering Report Proposed communications tower g Lincoln County, Oregon

In general, relatively wet/freezing climatic conditions prevail in the project area between November and May. During wet/freezing weather conditions, subgrade stability problems and grading difficulties may develop. The severity of earthwork related problems will be dependent, in part, on the precautions that are taken to protect the near surface soils from moisture. If construction is performed during wet weather, the placement of a granular working mat over the construction area may be necessary to protect exposed soils. We recommend that the granular protection mat within the construction areas consist of an adequate thickness of 2 to 4-inch clean crushed rock; areas exposed to wheeled vehicles will likely require a thicker mat of crushed rock during wet weather.

Earthwork on the project should be observed and evaluated by"... The evaluation of earthwork should include observation and testing of engineered fill, subgrade preparation, foundation bearing surfaces, and other geotechnical conditions exposed during the construction of the project.

4.3 Foundation Recommendations

• Based on the results of this exploration, it is our opinion that the tower can be supported by a mat foundation bearing directly on the andesite bedrock. Design recommendations for the mat foundation are presented in the following sections.

4.3.1 Mat Foundation Design Recommendations

A reinforced concrete mat foundation that bears on the andesite bedrock should be designed using the following parameters

DESCRIPTION

Mat Foundation

Bedrock 5,000 psf

Vertical Modulus of Subgrade Reaction 2 200 pci

Minimum dimensions 24 inches Minimum embedment below finished grade for frost protection 3

48 inches

Approximate total settlement 4 < 1/2 inch

6Allowable passive pressure. 250 pat/ft

Allowable coefficient of sliding friction 0.35

1 The recommended net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the foundation base elevation. Assumes undisturbed rock with any overbreak bad<filled with concrete or no more than 1 foot of SRSC. Factor of Safety used from the Ultimate Searing Pressure is 3.0.

PrqQpsed communications tower t Lincoln Count , Oregon

DESCRIPTION Mat Foundation

2. Applicable for a 1-foot by 1-foot loaded area.

3. And 10 reduce the effects Of seasonal moisture variations in the subgrade.

4. The foundation settlement will depend upon the variations within the subsurface profile, the structural loading Iconditions, the embedment depth of the mat, and the quality of the earthwork operations. The above settlement estimate assumes that the mat is about 5 feet square. Terracon should be allowed to verify the settlement estimate as design develops.

5. The value presented is an equivalent fluid pressure. The sides of Me excavation for the mat foundation must be nearly vertical and the concrete should be placed neat against these vertical faces for the passive earth pressure values to be valid. Passive resistance in the upper 24 inches of the soil profile should be neglected.

In general, when using the net allowable bearing pressures for evaluating foundation dimensions, the weight of the footings and backfill over the foundations need not be considered.

The above net allowable bearing pressure assumes that the mat has a minimum width of at least 5 feet.

4.3.2 Construction Considerations

Based on our experience with the jointed bedrock conditions, the contractor should expect some lateral variability of the bedrock surface in the foundation excavation. Thus, some overbreak should be anticipated in bedrock excavations due to potential variations in the bedrock conditions and excavation methodologies of the contractor. We recommend backfilling the areas of overbreak with concrete or no more than a 1-foot thick layer of CRC.

We recommend that the foundation construction be observed on a full-time basis by a Terracon representative in order to verify that conditions encountered are conoistant with the recommended design parameters.

4.4 Seismic Considerations

DESCRIPTION VALUE

2009 International Building Code Site Classification (IBC) I r2

N 44.955278

Site Latitude -.

Site Longitude- W 123.863333

Ss Spectral Acceleration for a Short Period l ' 1.273g

F,Site Coefficient for a Short Period 1.0

F, Site Coefficient for a 1-Second Period 1.3

I, Note . In general accordance with the 2009 International Ste/ding Code, Table 1613,5.2. IBC Site Class is based on the average characteristics of the upper 100 feet of the subsurface profile.

2. Motet The 2009 International Building Code ()BC) requires a she soil profile determination extending to a depth

Pro osed communications tower n Lincoln County ! Oregon of 100 feet for seismic site classification. The current scope does not . include the redutted 100 foot soil profile determination. The boring extended to a maximum depth of 19 feet, and this seismic site class definition considers that bedrock continues below the maximum depth of the subsurface exploration. Based on avatlable geologic publications as described in the Site Geology Section of this report and the subsurface conditions encountered in the boring, it is our opinion that the remaining 100 foot profile would consist of bedrock type materials similar to the andesite bedrock encountered. Therefore, we have considered the Site Class subsurface profile to consist of predominately andesite bedrock.

5.0 GENERAL COMMENTS

SI should be retained to review the final design plans and specifications so comments can be made regarding interpretation and implementation of our geotechnical recommendations in the design and specifications.all, also should be retained to provide observation and testing services during grading, excavation, foundation construction and other earth-related construction phases of the project.

The analysis and recommendations presented in this report are based upon the data obtained from the boring performed at the indicated location and from other information discussed in this .

report. This report does not reflect variations that may occur across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or . after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided.

The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such Contamination or pollution, other studies should be undertaken.

This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unlessall reviews the changes and either verifies or modifies the conclusions of this report in writing.

APPENDIX A

FIELD EXPLORATION

4'

4B-1

PROPOSED

TOWER

LOCATION

Approx. resistivity centerline

Existing tower location

Existing tower equipment shed

Gravel/dirt access road

LEGEND:

-4-B-1 APPROXIMATE BORING LOCATION AND NUMBER

APPROXIMATE LOCATION OF RESISTIVITY LINE

LNAGRAM IS FOR GENERAL LOCATION ONLY. AND IS NOT

INTENDED FOR CONSTRUCTION POR4OSES

BORING LOCATION DIAGRAM

COUGAR MOUNTAIN TOWER

N45° 57 19-, W123° 5148'

LINCOLN CITY, OREGON -

Exhibit

A-1

The exploration extended into the bedrock formation and samples of the rock were obtained by core drilling with an NO-size, diamond bit, core barrel. The core sample recovered with this barrel is approximately 2 inches in diameter. Coring of the bedrock was performed in general accordance with ASTM Standard D-2113. The length of core recovered and the ROD values (Rock Quality Designation) are shown on the log. ROD is the percent of total length cored consisting of sound pieces at least 4 inches in length and is a measure of the in-situ rock quality. ROD values characterize rock quality as excellent (90 - 100%). good (75 -90%), fair (50- 75%), poor (25-50%) and very poor (<25%).

The boring was completed under the —_—who visually inspected the soil/rock samples, prepared a log of the boring, interpreted stratigraphy, and classified and collected the samples. The boring log included visual classifications of the materials encountered during drilling, as Well as the geologist's interpretation of the subsurface conditions between samples.

Groundwater conditions were evaluated in the boring at the time of site exploration.

StIonessili Exhibit A-2

Geotechnical Engineering Report Proposed communications tower a Lincoln County, Oregon

INIMWS

Field Exploration Description .

The subsurface exploration included drilling one boring to a maximum depth of approximately 19 feet below the existing site grade. The proposed tower center was located by using a hand held GPS unit accurate to about ±20 feet. Input coordinates for location were provided to 11110.1Sle. The location of the boring should be Considered accurate only to the degree implied by the means and methods used to define them.

The approximate location of the boring is shown on the Boring Location Diagram.

The boring was drilled with a 4-wheel drive, truck-mounted drill rig using hollow stem auger drilling methods to advance the boring. Soil samples were obtained using split spoon sampling procedures in general accordance with.the standard penetration test (ASTM D1586). This test consists of driving the sampler into the ground with a 140-pound hammer free-falling through a distance of 30-indhes. The number of blows required to advance the sampler the last 12-inches, or the interval indicated, of a typical 18-inch penetration is recorded as the standard penetration resistance value (N-value). These values are indicated on the boring log at the respective sample depths.

4.

BORING LOG NO. B-1 Page 1 of 1

SITE

CLIENT

a -

19", VV123° 51' 48"

Otis, OR 97368

PROJECT

Tower N45° 57'

Cougar Mountain, Cougar Mountain

SAMPLES TESTS

o ...n DESCRIPTION o I cc

CI

0_

...n m

C.)

Le

'S W rc .

00 uj a's.r-c wij et

:f z u)

L— 94

u) m

2.e n-:

cr 14/ <Ou

Z

""0o la L9 ct:

LCu. 0 z 2 0 uj tt)F!

D V) oCi i eti

NT

e Ns, 4.

"4

N.

IL

Grass and 2 inch Root Zone over .GRAVELLY SILT, trace sand and organics

_ ML I SS 6 10

moist to r ' i

GRAVEL, with silt and sand, gray, dense, (SEVERLELY WEATHERED

ANDESITE)

_ GP 2 SS 2 38

damp to moist

very close to soft to close joints

S ., DB

60%

50/4"

ROD

44% black pymxene crystals, moderate weathering, medium hardness, to close joints -auger refusal at 4,8; start coring

-lost circulation at - 8'

-with black and white crystals, moderate moderately severe weathering, medium hardness, very close to

-moderately close joints ii

7-

5 08 48% ROD

23%

6 OB 60% ROD

35%15,-

BOTTOM OF BORING

Boring advanced using hollow-stem augers to 4.8'. Diamond bit coring to bottom of boring.

RIG II.

MLE

DRILLER

JOB//

WM

NIP

SW*

WL

WL

T V ---

LOGGED

APPENDIX B

LABORATORY TESTING

11111111MGeotechnical Engineering Report Proposed communications tower • Lincoln County, Oregon 1411.1111allar

Laboratory Testing .

Samples obtained during the field exploration were visually classified in the laboratory in general accordance with the Unified Soil Classification System (USCS). Classification of rock materials was in accordance with the attached General Notes Rock Classification and has been estimated from the rock cores obtained. No laboratory testing other than visual classification was completed for this study. Petrographic analysis may indicate other rock types. A brief description of these classification systems is included in Appendix C.

Descriptive classifications of the soils/rock indicated on the boring logs are in accordance with the enclosed General Notes and the Unified Soil Classification System. Also shown are estimated Unified Soil Classification Symbols. All classification was by visual manual procedures.

Exhibit B-1

APPENDIX C

SUPPORTING DOCUMENTS

GENERAL NOTES

DRILLING & SAMPLING SYMBOLS:

SS: Split Spoon - 1-4/8"1.0., 2 00., unless otherwise noted HS. Hollow Stem Auger $T: Thin-Walled Tube -2" OD., unless otherwise noted PA: Power Auger RS: Ring Sampler - 2.42" ID., 3" 0.D., unless Otherwise noted HA: Hand Auger DB: Diamond Bit Coring - 4", N, B Re: Rock Bit Ei& Bulk Sample or Auger Sample We: Wash Boring or Mud Rotary

The number of blows required to advance a standard 2-inch 0.0. split-spoon sampler (SS) the last 12 inches of the total 18-inch penetration with a 140-pound hammer falling 30 inches is considered the "Standard Penetration' or "N-value".

WATER LEVEL MEASUREMENT SYMBOLS:

While Sampling

N/E: Not Encountered While Drilling Before Casing Removal After Casing Removal

Water levels indicated on the exploration logs are the levels measured in the explorations at the limes indicated. Groundwater levels at other times and other locations across the site could vary. In pervious soils, the indicated levels may reflect the location of groundwater. In low permeability soils, the accurate determination of groundwater levels may not be possible with only shod-term observations.

DESCRIPTIVE SOIL CLASSIFICATION: Soil classification is based on the Unified Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve, their principal descriptors are: boulders, cobbles, gravel or sand, Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency.

CONSISTENCY OF FINE-GRAINED SOILS RELATIVE DENSITY OF COARSE-GRAINED SQL-5

Unconfined Standard Penetration Standard Penetration

Compressive or N-value (SS) Consistenc_y or N-value ($S) Relative DensiR Strength Qu, psi Blows/FL Blows/FL

. <530 0 - 1 Very Soft 0 - 3 \ Very Loose 500 - 1,000 2 - 4 Soft 4-9 Loose

1,001 -2,000 4 - 8 Medium Stiff 10 - 29 Medium Dense 2,001 -4,000 6-15 Stiff 30 - 49 Dense 4,001 -8,000 15 - 30 Very Stiff >50 Very Dense

8,000+ > 30 Hard

RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY

Descriptive Term(s) of other Percent of Major Component Particle Size

Constituents Dry Weight • of Sample Trace <15 Boulders Over 12 in. (300mm) With 15 - 29 Cobbles 12 in. to 3 in. 1300mm to 75 mm)

Modifier > 30 Gravel 3 in. to #4 sieve (75mm to 4.75 mm) Sand #4 to #200 sieve (4.75mm to 0.075mm)

Silt or Clay Passing #200 Sieve (0 075mm)

RELATIVE PROPORTIONS OF FINES PLASTICITY DESCRIPTION

Descriptive Term(s) of other Percent of Term

Plasticity Constituents Dry Weight Index

Trace e 5 Non -plastic U With 5 -12 Low 1-10

Modifiers > 12 Medium 11 - 30 High >33

Exhibit C-1

Liquid limit - oven dried Liquid limit not dried 0.75 DL

Organic silt m"

Organic Clay“

0 30 40 50 60 70

LIQUID LIMIT I'LL)

BO 90 tDO10 10 20

X 40UJ

1— o

Ct

For classification of line-grained soils and fine-grained fraction

-of coarse-grained soils Equation of "A" • line Horizontal at P1=-4 to LL=26.5 lhon P1=0.73 (LL-20)

Equation oi - Vertical at Aka to P14.2.

then P1=0.9 (LL-8) it

UNIFIED SOIL CLASSIFICATION SYSTEM

Soil Classification Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests Group Group NameSymbol

Gravels:

More than 50% of coarse fraction retained on No. 4 sieve

Sands:

50% or more of coarse fraction passes No.4 sieve

Clean Gravels:

Less than 5% fines Gravels with Fines:

More than 12% fines' Clean Sands:

Less than 5% fines° Sands with Fines:

More than 12% fines

Cu 2: 4 and 1 5. Cc 5 3' • Cu 4 and/or I Cc > 3E.

Fines classify as ML or MI-I Fines classify aS CL or CH Cu 6 and 1 eCcs1 Cu 6 and/or I :., Cc Fines classrfy as ML or MH Fines classify as CL or CH, OW Well-graded gravel

svv Wed-graded sand sp Poorly graded sand l• sm Silty Sand Hi

Sc Clayey sand

Coarse Grained Soils:

More than 50% retained on No. 200 sieve

Silts and Clays:

Liquid limit less than 50

P1>7 and OlOts on or above "A" Poe CL . Lean day"' I" PI 4 or plots below A Me'

ML Silt

Fine-Grained Soils:

50% or more passes the No. 200 sieve

Silts and Clays:

Liquid limii 50 or more

Inorganic:

Organic:

Inorganic:

Organic:

Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

Based on tne material passing the 3-in 110-Inin) sieve n If field sample contained cobbles or boulders, or both, add 'with cobbles or boulders, or both" to group name, 6 Gravels with 5 to 12% fines require dual symbols: OW-GM wet-graded gravel with silt. SW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC goody graded gravel with day.

D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt. SW-SC wet-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay

)2

E CU = 06010,D CC = —

f1 10 060

F If soli contains 15% sand. add "with sand" to group name.

O If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.

"If fines are organic, ago win Organic fines" to group name.

r If soil contains i 15% gravel. add 'with graver to group name.

J. If Aderberg limits plot in shaded area, sail is a cLant., silty clay.

soil contains 15 to 29% plus No. 200, add :with sand" or "with gravel," whichever is predominant.

If soil contains 30% plus No. 200 p redominantly sand, add "sandy' . to grou p name.

m If soil contains 'L. 30% plus No. 200, Predomina ntly gravel, add "gravelly" to group name.

" PI 4 and plots on or above "A" I:ne.

°Pt 401 plots below "X' line, P PI pink on or abrote line.

°PI plots below 'A" line.

Exhibit C-2