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Geotechnical Engineering Report CR 44H Structures

Approx. 10 miles of CR 44H from Ballard Road east to CR 27

Larimer County, Colorado

November 6, 2015

Terracon Project No. 20155038

Prepared for:

AVI PC

Fort Collins, Colorado

Prepared by:

Terracon Consultants, Inc.

Fort Collins, Colorado

TABLE OF CONTENTS

Page

EXECUTIVE SUMMARY ............................................................................................................ i 1.0 INTRODUCTION .............................................................................................................1 2.0 PROJECT INFORMATION .............................................................................................1

2.1 Project Description ...............................................................................................1 2.2 Site Location and Description...............................................................................2

3.0 SUBSURFACE CONDITIONS ........................................................................................2 3.1 Typical Subsurface Profile ...................................................................................2 3.2 Laboratory Testing ...............................................................................................3 3.3 Corrosion Protection ............................................................................................3 3.4 Groundwater ........................................................................................................3

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION ......................................4 4.1 Geotechnical Considerations ...............................................................................4

4.1.1 Existing, Undocumented Fill .....................................................................4 4.1.2 Shallow Groundwater ...............................................................................4 4.1.3 Foundation Recommendations .................................................................5

4.2 Earthwork.............................................................................................................5 4.2.1 Site Preparation ........................................................................................5 4.2.2 Excavation ................................................................................................6 4.2.3 Subgrade Preparation ...............................................................................7 4.2.4 Fill Materials and Placement ......................................................................7 4.2.5 Compaction Requirements ........................................................................9 4.2.6 Grading and Drainage ...............................................................................9

4.3 Foundations .......................................................................................................10 4.3.1 Spread Footings - Design Recommendations .........................................11 4.3.2 Spread Footings - Construction Considerations ......................................12

4.4 Seismic Considerations......................................................................................12 4.5 Lateral Earth Pressures .....................................................................................13

5.0 GENERAL COMMENTS ...............................................................................................14

TABLE OF CONTENTS (continued)

Appendix A – FIELD EXPLORATION

Exhibit A-1 Site Location Map

Exhibits A-2 to A-13 Exploration Plan

Exhibit A-14 Field Exploration Description

Exhibits A-15 to A-46 Boring Logs

Appendix B – LABORATORY TESTING

Exhibit B-1 Laboratory Testing Description

Exhibit B-2 Atterberg Limits Test Results

Exhibits B-3 to B-9 Grain-size Distribution Test Results

Exhibits B-10 to B-13 Water-soluble Sulfate Test Results

Appendix C – SUPPORTING DOCUMENTS

Exhibit C-1 General Notes

Exhibit C-2 Unified Soil Classification System

Exhibit C-3 Description of Rock Properties

Exhibit C-4 Laboratory Test Significance and Purpose

Exhibits C-5 and C-6 Report Terminology

Geotechnical Engineering Report CR 44H Structures ■ Larimer County, Colorado November 6, 2015 ■ Terracon Project No. 20155038

Responsive ■ Resourceful ■ Reliable i

EXECUTIVE SUMMARY

A geotechnical investigation has been performed for the proposed CR 44H Structures to be

constructed along approximately 10 miles of CR 44H from Ballard Road east to CR 27 in Larimer

County, Colorado. Thirty-two (32) borings, presented as Exhibits A-15 through A-46 and

designated as Boring No. 1 through Boring No. 32, were performed to depths of approximately 7 to

22½ feet below existing site grades. This report specifically addresses the recommendations for

the proposed replacement box culverts. Borings performed in these areas are for informational

purposes and will be utilized by others.

Based on the information obtained from our subsurface exploration, the site can be developed for

the proposed project. However, the following geotechnical considerations were identified and will

need to be considered:

Existing, undocumented fill was encountered in the borings performed on this site to depths

ranging from about 2½ to 9 feet below existing site grades. The fill was likely placed during

construction of the existing metal culverts, roadway embankments, and/or deposited during

a recent flood event. We anticipate the proposed foundations will extend to depths below

the encountered fill materials. If the proposed foundations will not extend below the

encountered fill materials, the existing fill soils should be removed and replaced with

engineered fill beneath proposed foundations.

The proposed culverts may be supported on shallow spread footing foundations bearing

on properly prepared on-site soils or properly placed imported fill.

Very hard bedrock was encountered at depths ranging from 6 to 21 feet below the existing

site grades. Excavation penetrating the bedrock (if any) may require the use of

specialized heavy-duty equipment, together with ripping or jack-hammering to advance

the excavation and facilitate rock break-up and removal. Consideration should be given

to obtaining a unit price for difficult excavation in the contract documents for the project.

Groundwater was encountered at depths ranging from 4 to 10 feet below the existing site

grades. We anticipate construction dewatering will be required for construction of the

foundations of the proposed culverts. AS water flows increase within the drainage area,

dewatering will require more significant effort.

The amount of movement of foundations will be related to the wetting of underlying

supporting soils. Therefore, it is imperative the recommendations discussed in the 4.2.6

Grading and Drainage section of this report be followed to reduce potential movement.

The 2012 International Building Code, Table 1613.5.2 IBC seismic site classification for this

site ranges from C to D. The table in the 4.4 Seismic Considerations section of this

report presents which structures are classified as site class C or D.


Responsive ■ Resourceful ■ Reliable ii

Close monitoring of the construction operations discussed herein will be critical in

achieving the design subgrade support. We therefore recommend that Terracon be

retained to monitor this portion of the work.

This summary should be used in conjunction with the entire report for design purposes. It

should be recognized that 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.

Responsive ■ Resourceful ■ Reliable 1

GEOTECHNICAL ENGINEERING REPORT

CR 44H Structures

Approx. 10 miles of CR 44H from Ballard Road east to CR 27

Larimer County, Colorado Terracon Project No. 20155038

November 6, 2015

1.0 INTRODUCTION

This report presents the results of our geotechnical engineering services performed for the

proposed CR 44H Structures to be constructed along approximately 10 miles of CR 44H from

Ballard Road east to CR 27 in Larimer County, Colorado (Exhibit A-1). The purpose of these

services is to provide information and geotechnical engineering recommendations relative to:

subsurface soil and bedrock conditions foundation design and construction

groundwater conditions earthwork

grading and drainage lateral earth pressures

seismic considerations

Our geotechnical engineering scope of work for this project included the initial site visit, the

advancement of 32 test borings to depths of approximately 7 to 22½ feet below existing site

grades, laboratory testing for soil engineering properties and engineering analyses to provide

box culvert foundation design and construction recommendations.

Logs of the borings along with an Exploration Plan (Exhibit A-2) are included in Appendix A.

More detailed, “zoomed in” Exploration Plans for each portion of the alignment are presented as

Exhibits A-3 through A-13 in Appendix A. The results of the laboratory testing performed on soil

and bedrock samples obtained from the site during the field exploration are included in

Appendix B.

2.0 PROJECT INFORMATION

2.1 Project Description

Item Description

Site layout Refer to the Exploration Plans (Exhibits A-2 through A-13 in Appendix A)

Proposed construction

We understand 17 three-sided, concrete box culverts will be constructed

along CR 44H. The structures will be approximately 10 feet tall by 20

feet wide.

Grading We anticipate cuts and fills on the order of 12 to 15 feet will be required

for the proposed construction.



Item Description

Cut and fill slopes Assumed to be no steeper than 3H:1V (Horizontal to Vertical)

2.2 Site Location and Description

Item Description

Location

The 17 structures are planned along approximately 10 miles of CR 44H

starting approximately 900 feet west of Ballard Road and CR 44H and

continuing east in Larimer County, Colorado.

Existing improvements

CR 44H is a gravel-surfaced roadway with several metal pipe culvert

crossings. We understand the flood event in 2013 damaged several

locations along this roadway. Temporary crossings were constructed at

several locations as well as reconstruction of several sections of the

roadway.

Current ground cover The ground is covered with gravel surfacing, native plants, mature trees,

and some riprap.

Existing topography The roadway surface is relatively flat with several shear rock

outcroppings and shoulder drop-offs sloping towards Buckhorn Creek.

3.0 SUBSURFACE CONDITIONS

3.1 Typical Subsurface Profile

Specific conditions encountered at each boring location are indicated on the individual boring

logs included in Appendix A. Stratification boundaries on the boring logs represent the

approximate location of changes in soil types; in-situ, the transition between materials may be

gradual. Based on the results of the borings, subsurface conditions on the project site can be

generalized as follows:

Material Description Approximate Depth to Bottom of

Stratum (feet) Consistency/Density/Hardness

Gravel surfacing About 4 to 30 inches thick. --

Fill materials consisting of silt,

lean clay, sand, gravel, and

cobbles

About 2½ to 9 feet below existing

site grades in Boring Nos. 2, 11, 12,

17, 21, 22, 24, 25, 26, 27, and 32.

--

Sand with silt, gravel, and

cobbles/boulders

About 6 to 21 feet below existing

site grades. Very loose to very dense

Sandy lean clay About 6 feet below the existing site

grade in Boring No. 6 only Medium stiff to very stiff

Schist bedrock To the maximum depth of

exploration of about 25 feet.

Hard to very hard (highly

cemented



3.2 Laboratory Testing

Samples of site soils selected for plasticity testing exhibited non-plastic to medium plasticity with

liquid limits ranging from non-plastic to 36 and plasticity indices ranging from 3 to 17.

Laboratory test results are presented in Appendix B.

3.3 Corrosion Protection

Results of water-soluble sulfate testing indicate that ASTM Type I or II portland cement should

be specified for all project concrete on and below grade. Foundation concrete should be

designed for low sulfate exposure in accordance with the provisions of the ACI Design Manual,

Section 318, Chapter 4.

3.4 Groundwater

The boreholes were observed while drilling and after completion for the presence and level of

groundwater. In addition, delayed water levels were also obtained in some borings. The water

levels observed in the boreholes are noted on the attached boring logs, and are summarized

below:

Boring Number Depth to groundwater

while drilling, ft. Boring Number

Depth to groundwater

while drilling, ft.

1 7 17 7

2 9 18 9

3 4 19 5

4 7 20 8

5 7 21 7

6 7 22 9

7 7 23 9

8 4 24 8

9 7 25 9

10 9 26 10

11 9 27 8

12 7 28 10

13 5.5 29 10

14 5.5 30 11

15 10 31 9

16 7.5 32 9

These observations represent groundwater conditions at the time of the field exploration, and

may not be indicative of other times or at other locations. Groundwater levels can be expected



to fluctuate with varying seasonal and weather conditions, and other factors.

Groundwater level fluctuations occur due to seasonal variations in the water levels present in

the Buckhorn Creek, amount of rainfall, runoff and other factors not evident at the time the

borings were performed. Therefore, groundwater levels during construction or at other times in

the life of the structures may be higher or lower than the levels indicated on the boring logs.

The possibility of groundwater level fluctuations should be considered when developing the

design and construction plans for the project.

4.0 RECOMMENDATIONS FOR DESIGN AND CONSTRUCTION

4.1 Geotechnical Considerations

Based on subsurface conditions encountered in the borings, the site appears suitable for the

proposed construction from a geotechnical point of view provided certain precautions and

design and construction recommendations described in this report are followed. We have

identified geotechnical conditions that could impact design and construction of the proposed

structures and other site improvements.

4.1.1 Existing, Undocumented Fill

As previously noted, existing fill was encountered to depths up to about 9 feet in the borings

drilled at the site. We do not possess any information regarding whether the fill was placed

under the observation of a geotechnical engineer. The fill was likely placed during construction of

the existing metal culverts, roadway embankments, and/or deposited during a recent flood event.

We anticipate the proposed foundations will extend to depths below the encountered fill materials.

If the proposed foundations will not extend below the encountered fill materials, the existing fill soils

should be removed and replaced with engineered fill beneath proposed foundations.

Support of footings on or above existing fill soils is discussed in this report. However, even with

the recommended construction testing services, there is an inherent risk for the owner that

compressible fill or unsuitable material within or buried by the fill will not be discovered. This risk

of unforeseen conditions cannot be eliminated without completely removing the existing fill, but

can be reduced by performing additional testing and evaluation. However, we anticipate the

footing elevations will extend below the existing fill materials.

4.1.2 Shallow Groundwater

As previously stated, groundwater was measured at depths ranging from about 4 to 10 feet

below existing site grades. We anticipate construction dewatering will be required for the

proposed construction. It is also possible and likely that groundwater levels below this site will

rise as water levels in the Buckhorn Creek rise.



4.1.3 Foundation Recommendations

The proposed culverts may be supported on spread footing foundation systems bearing on

properly prepared on-site soils or properly placed imported fill.

Bedrock was encountered at depths ranging from 6 to 21 feet below existing site

grades. Without any ground modifications, shallow footing foundations may be partially

constructed on bedrock and partially constructed on soil. We believe different foundation

support conditions below various portions of the footing foundations would result in a risk for

differential foundation movements. The magnitude of the differential movement would depend

on foundation loading conditions.

In areas where foundations will bear partially on bedrock and partially on soil, we recommend

over-excavating the bedrock and replacing with properly prepared on-site soils or imported

engineered fill to a depth that will allow equal thicknesses of soil between continuous footings

and bedrock. If half of a culvert (on one side of the creek) will bear on soil and the other half of

the culvert (on the opposite side of the creek) will bear on bedrock, we recommend over-

excavating the bedrock a minimum depth of 2 feet, and replacing the excavated bedrock with

properly placed engineered fill. On-site soils area suitable for use as engineered fill provided

they are properly prepared as presented in the 4.2 Earthwork section of this report. In areas

where the footings will bear on the bedrock, the bearing surface of the bedrock should be

thoroughly cleaned to remove any loose bedrock pieces.

4.2 Earthwork

The following presents recommendations for site preparation, excavation, subgrade preparation

and placement of engineered fills on the project. All earthwork on the project should be

observed and evaluated by Terracon on a full-time basis. The evaluation of earthwork should

include observation of over-excavation operations, testing of engineered fills, subgrade

preparation, subgrade stabilization, and other geotechnical conditions exposed during the

construction of the project.

4.2.1 Site Preparation

Prior to placing any fill, strip and remove existing vegetation (if any), the depth of existing fill, and

any other deleterious materials from the proposed construction areas.

Stripped organic materials should be wasted from the site or used to re-vegetate exposed slopes

after completion of grading operations. Prior to the placement of fills, the site should be graded to

create a relatively level surface to receive fill, and to provide for a relatively uniform thickness of fill

beneath proposed structures.

If fill is placed in areas of the site where existing slopes are steeper than 5:1 (horizontal:vertical),

the area should be benched to reduce the potential for slippage between existing slopes and fills.



Benches should be wide enough to accommodate compaction and earth moving equipment, and

to allow placement of horizontal lifts of fill.

Demolition of the existing steel culverts and temporary crossings should include complete removal

of all foundation components (if any) within the proposed construction areas. This should include

removal of any utilities to be abandoned along with any loose utility trench backfill or loose backfill

found adjacent to existing foundations. All materials derived from the demolition of the existing

structures should be removed from the site, and not be allowed for use in any on-site fills.

4.2.2 Excavation

It is anticipated that excavations for the proposed construction not penetrating bedrock can be

accomplished with conventional earthmoving equipment. Excavations into the on-site soils will

encounter weak and/or saturated soil conditions with possible caving conditions.

Excavation penetrating the bedrock may require the use of specialized heavy-duty equipment,

together with ripping or jack-hammering to advance the excavation and facilitate rock break-up

and removal. Consideration should be given to obtaining a unit price for difficult excavation in the

contract documents for the project.

The soils to be excavated can vary significantly across the site as their classifications are based

solely on the materials encountered in widely-spaced exploratory test borings. The contractor

should verify that similar conditions exist throughout the proposed area of excavation. If different

subsurface conditions are encountered at the time of construction, the actual conditions should be

evaluated to determine any excavation modifications necessary to maintain safe conditions.

Although evidence of underground facilities such as septic tanks, vaults, and basements was not

observed during the site reconnaissance, such features could be encountered during construction.

If unexpected fills or underground facilities are encountered, such features should be removed

and the excavation thoroughly cleaned prior to backfill placement and/or construction.

Any over-excavation that extends below the bottom of foundation elevation should extend laterally

beyond all edges of the footings at least 8 inches per foot of over-excavation depth below the

footing base elevation. The over-excavation should be backfilled to the footing base elevation in

accordance with the recommendations presented in this report.

Depending upon depth of excavation and seasonal conditions, surface water infiltration and/or

groundwater may be encountered in excavations on the site. It is anticipated that pumping from

sumps may be utilized to control water within excavations. Well points may be required for

significant groundwater flow, or where excavations penetrate groundwater to a significant depth.

Groundwater seepage should be anticipated for excavations approaching the level of bedrock.

The subgrade soil conditions should be evaluated during the excavation process and the stability

of the soils determined at that time by the contractors’ Competent Person. Slope inclinations



flatter than the OSHA maximum values may have to be used. The individual contractor(s) should

be made responsible for designing and constructing stable, temporary excavations as required to

maintain stability of both the excavation sides and bottom. All excavations should be sloped or

shored in the interest of safety following local, and federal regulations, including current OSHA

excavation and trench safety standards.

As a safety measure, it is recommended that all vehicles and soil piles be kept a minimum lateral

distance from the crest of the slope equal to the slope height. The exposed slope face should be

protected against the elements

4.2.3 Subgrade Preparation

After the existing fill below proposed footings (if any) and any other deleterious materials have

been removed from the construction area, the top 8 inches of the exposed ground surface

should be scarified, moisture conditioned, and recompacted to at least 95 percent of the

maximum dry unit weight as determined by ASTM D698 before any new fill or foundation is

placed.

If pockets of soft, loose, or otherwise unsuitable materials are encountered at the bottom of the

footing excavations and it is inconvenient to lower the footings, the proposed footing elevations

may be reestablished by over-excavating the unsuitable soils and backfilling with compacted

engineered fill. Any over-excavation should be performed in accordance with the excavation

recommendations given below.

In addition, large cobbles or boulder-sized materials may be encountered beneath footing areas.

Such conditions could create point loads on the bottom of footings, increasing the potential for

differential foundation movement. If such conditions are encountered in the footing excavations,

the cobbles and/or boulders should be removed and be replaced with engineered fill,

conditioned to near optimum moisture content and compacted.

After the bottom of the excavation has been compacted, engineered fill can be placed to bring

the foundations to the desired grade. Engineered fill should be placed in accordance with the

recommendations presented in subsequent sections of this report.

The stability of the subgrade may be affected by precipitation, repetitive construction traffic or

other factors. If unstable conditions develop, workability may be improved by scarifying and

drying. Alternatively, over-excavation of wet zones and replacement with granular materials

may be used, or crushed gravel and/or rock can be tracked or “crowded” into unstable subgrade

surface soils until a stable working surface is attained. Lightweight excavation equipment may

also be used to reduce subgrade pumping.

4.2.4 Fill Materials and Placement

The on-site soils or approved granular and low plasticity cohesive imported materials may be used

as fill material. The soil removed from this site that is free of organic or objectionable materials,



as defined by a field technician who is qualified in soil material identification and compaction

procedures, can be re-used as fill for the culvert foundations. Bedrock excavated from the site

(if any) should be thoroughly processed and broken down to pieces no larger than 4 inches in

size prior to re-use as fill. It should be noted that on-site soils may require reworking to adjust

the moisture content to meet the compaction criteria.

Imported soils (if required) should meet the following material property requirements:

Gradation Percent finer by weight (ASTM C136)

4” 100

3” 70-100

No. 4 Sieve 50-100

No. 200 Sieve 15-50

Soil Properties Value

Liquid Limit 30 (max.)

Plastic Limit 5 (max.)

Maximum Expansive Potential (%) Non-expansive1

1. Measured on a sample compacted to approximately 95 percent of the maximum dry unit weight as

determined by ASTM D698 at optimum moisture content. The sample is confined under a 100 psf

surcharge and submerged.



4.2.5 Compaction Requirements

Engineered fill should be placed and compacted in horizontal lifts, using equipment and

procedures that will produce recommended moisture contents and densities throughout the lift.

Item Description

Fill lift thickness

9 inches or less in loose thickness when heavy, self-

propelled compaction equipment is used

4 to 6 inches in loose thickness when hand-guided

equipment (i.e. jumping jack or plate compactor) is used

Minimum compaction requirements 95 percent of the maximum dry unit weight as determined

by ASTM D698

Moisture content cohesive soil (clay) -1 to +3 % of the optimum moisture content

Moisture content cohesionless soil

(sand) -3 to +2 % of the optimum moisture content

1. We recommend engineered 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.

2. Specifically, moisture levels should be maintained low enough to allow for satisfactory compaction

to be achieved without the fill material pumping when proofrolled.

3. Moisture conditioned clay materials should not be allowed to dry out. A loss of moisture within

these materials could result in an increase in the material’s expansive potential. Subsequent

wetting of these materials could result in undesirable movement.

The recommendations for placement and compaction criteria presented assume that fill depths

will be less than 8 feet. Fills on the order of 8 feet in depth, when placed and compacted as

recommended in this report, will experience some settlement, generally 1 inch or less. The

amount and rate of settlement will be increased if water is introduced into the fill. It is noted that

settlement of the fill material due to self-weight is in addition to settlements due to structural

induced loads. In areas where fill will be placed in thicknesses of 8 feet or more, we

recommend increasing the minimum compaction requirements to 98 percent of the maximum

dry unit weight as determined by ASTM D698.

4.2.6 Grading and Drainage

All grades must be adjusted to provide effective drainage away from the proposed culverts

during construction and maintained throughout the life of the proposed project. Infiltration of

water into foundation excavations must be prevented during construction. Water permitted to

pond near or adjacent to the perimeter of the structures (either during or post-construction) can

result in significantly higher soil movements than those discussed in this report. As a result, any

estimations of potential movement described in this report cannot be relied upon if positive

drainage is not obtained and maintained, and water is allowed to infiltrate the fill and/or

subgrade.



Exposed ground (if any) should be sloped at a minimum of 10 percent grade for at least 10 feet

beyond the perimeter of the proposed culverts, where possible. The use of swales, chases

and/or area drains may be required to facilitate drainage in unpaved areas around the perimeter

of the culverts. Backfill against footings and exterior walls should be properly compacted and

free of all construction debris to reduce the possibility of moisture infiltration. After construction

of the proposed culverts and prior to project completion, we recommend verification of final

grading be performed to document positive drainage, as described above, has been achieved.

4.3 Foundations

The proposed culverts may be supported on spread footing foundation systems bearing on

properly prepared on-site soils or properly placed imported fill. Bedrock was encountered at

depths ranging from 6 to 21 feet below existing site grades. Without any ground modifications,

shallow footing foundations may be partially constructed on bedrock and partially constructed on

soil. We believe different foundation support conditions below various portions of the footing

foundations would result in a risk for differential foundation movements. The magnitude of the

differential movement would depend on foundation loading conditions.

In areas where foundations will bear partially on bedrock and partially on soil, we recommend

over-excavating the bedrock and replacing with properly prepared on-site soils or imported

engineered fill to a depth that will allow equal thicknesses of soil between continuous footings and

bedrock. If half of a culvert (on one side of the creek) will bear on soil and the other half of the

culvert (on the opposite side of the creek) will bear on bedrock, we recommend over-excavating

the bedrock a minimum depth of 2 feet, and replacing the excavated bedrock with properly placed

engineered fill. On-site soils area suitable for use as engineered fill provided they are properly

prepared as presented in the 4.2 Earthwork section of this report. In areas where the footings

will bear on the bedrock, the bearing surface of the bedrock should be thoroughly cleaned to

remove any loose bedrock pieces.

Design recommendations for foundations for the proposed structures and related structural

elements are presented in the following sections.



4.3.1 Spread Footings - Design Recommendations

Description Value

Maximum allowable bearing pressure 1 On-site soils or imported fill: 3,000 psf

Bedrock: 5,000 psf

Lateral earth pressure coefficients 2

Lean clay:

Active, Ka = 0.41

Passive, Kp = 2.46

At-rest, Ko = 0.58

Granular soil/fill:

Active, Ka = 0.27

Passive, Kp = 3.69

At-rest, Ko = 0.43

Sliding coefficient 2 Granular soil/fill:

µ = 0.56

Moist soil unit weight

Lean clay:

ɣ = 120 pcf

Granular soil/fill:

ɣ = 130 pcf

Minimum embedment depth below finished

grade 3 30 inches

Estimated total movement 4 About 1 inch

Estimated differential movement 4 About ½ to ¾ of total movement

1. The recommended maximum allowable bearing pressure assumes any unsuitable fill or soft soils,

if encountered, will be over-excavated and replaced with properly compacted engineered fill.

The design bearing pressure applies to a dead load plus design live load condition. The design

bearing pressure may be increased by one-third when considering total loads that include wind or

seismic conditions.

2. The lateral earth pressure coefficients and sliding coefficients are ultimate values and do not

include a factor of safety. The foundation designer should include the appropriate factors of

safety.

3. For frost protection and to reduce the effects of seasonal moisture variations in the subgrade

soils. The minimum embedment depth is for perimeter footings beneath unheated areas and is

relative to lowest adjacent finished grade, typically exterior grade.

4. The estimated movements presented above are based on the assumption that the maximum

footing size is 3 feet for continuous footings.

Footings should be proportioned to reduce differential foundation movement. As discussed,

total movement resulting from the assumed structural loads is estimated to be on the order of

about 1 inch. Additional foundation movements could occur if water from any source infiltrates

the foundation soils; therefore, proper drainage should be provided in the final design and



during construction and throughout the life of the structure. Failure to maintain the proper

drainage as recommended in the 4.2.6 Grading and Drainage section of this report will nullify

the movement estimates provided above.

4.3.2 Spread Footings - Construction Considerations

Spread footing construction should only be considered if the estimated foundation movement

can be tolerated. Subgrade soils beneath footings should be moisture conditioned and

compacted as described in the 4.2 Earthwork section of this report. The moisture content and

compaction of subgrade soils should be maintained until foundation construction.

Footings and foundation walls should be reinforced as necessary to reduce the potential for

distress caused by differential foundation movement.

Unstable subgrade conditions are anticipated as excavations approach the groundwater

surface. Unstable surfaces will need to be stabilized prior to backfilling excavations and/or

constructing the culvert foundations. The use of angular rock, recycled concrete and/or gravel

pushed or “crowded” into subgrade soils is considered suitable means of stabilizing the

subgrade. The use of geogrid materials in conjunction with gravel could also be considered and

could be more cost effective.

Unstable subgrade conditions should be observed by Terracon to assess the subgrade and

provide suitable alternatives for stabilization. Stabilized areas should be proof-rolled prior to

continuing construction to assess the stability of the subgrade.

Foundation excavations should be observed by Terracon. If the soil conditions encountered

differ significantly from those presented in this report, supplemental recommendations will be

required.

4.4 Seismic Considerations

Code Used 2012 International Building Code (IBC)1

Site Classification C 2 Site Classification D 2

Structure Nos. Structure Nos.

4, 7, 9, 12, 13, and 16 1, 2, 3, 5, 6, 8, 10, 11, 14, 15, and 17

1. In general accordance with the 2012 International Building Code, Table 1613.5.2.

2. The 2012 International Building Code (IBC) requires a site soil profile determination extending a

depth of 100 feet for seismic site classification. The current scope requested does not include the

required 100 foot soil profile determination. The borings completed for this project extended to a

maximum depth of about 22½ feet and this seismic site class definition considers that similar soil and

bedrock conditions exist below the maximum depth of the subsurface exploration. A geophysical

exploration could be utilized in order to attempt to justify a more favorable seismic site class.



4.5 Lateral Earth Pressures

Reinforced concrete walls with unbalanced backfill levels on opposite sides should be designed

for earth pressures at least equal to those indicated in the following table. Earth pressures will

be influenced by structural design of the walls, conditions of wall restraint, methods of

construction and/or compaction and the strength of the materials being restrained. Two wall

restraint conditions are shown. Active earth pressure is commonly used for design of

free-standing cantilever retaining walls and assumes wall movement. The "at-rest" condition

assumes no wall movement. The recommended design lateral earth pressures do not include a

factor of safety and do not provide for possible hydrostatic pressure on the walls.

EARTH PRESSURE COEFFICIENTS

Earth Pressure Conditions

Coefficient for Backfill Type

Equivalent Fluid Density (pcf)

Surcharge Pressure,

p1 (psf)

Earth Pressure,

p2 (psf)

Active (Ka) Granular soil/fill - 0.27

Lean Clay - 0.41

35

49

(0.27)S

(0.41)S

(35)H

(49)H

At-Rest (Ko) Granular soil/fill - 0.43

Lean Clay - 0.58

56

70

(0.46)S

(0.58)S

(55)H

(70)H

Passive (Kp) Granular soil/fill - 3.69

Lean Clay - 2.46

480

295

---

---

---

---

Applicable conditions to the above include:

For active earth pressure, wall must rotate about base, with top lateral movements of about

0.002 H to 0.004 H, where H is wall height;

For passive earth pressure to develop, wall must move horizontally to mobilize resistance;



Uniform surcharge, where S is surcharge pressure;

In-situ soil backfill weight a maximum of 120 pcf;

Horizontal backfill, compacted between 95 and 98 percent of maximum dry unit weight as

determined by ASTM D698;

Loading from heavy compaction equipment not included;

No hydrostatic pressures acting on wall;

No dynamic loading;

No safety factor included in soil parameters; and

Ignore passive pressure in frost zone.

To control hydrostatic pressure behind the wall we recommend that a drain be installed at the

foundation wall with a collection pipe leading to a reliable discharge. If this is not possible, then

combined hydrostatic and lateral earth pressures should be calculated for lean clay backfill

using an equivalent fluid weighing 90 and 100 pcf for active and at-rest conditions, respectively.

For granular backfill, an equivalent fluid weighing 85 and 90 pcf should be used for active and

at-rest, respectively. These pressures do not include the influence of surcharge, equipment or

floor loading, which should be added. Heavy equipment should not operate within a distance

closer than the exposed height of retaining walls to prevent lateral pressures more than those

provided.

5.0 GENERAL COMMENTS

Terracon 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. Terracon 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 borings performed at the indicated locations and from other information discussed in

this report. This report does not reflect variations that may occur between borings, 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, and 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 described in this report are

planned, the conclusions and recommendations contained in this report shall not be considered

valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this

report in writing.

APPENDIX A

FIELD EXPLORATION

TOPOGRAPHIC MAP IMAGE COURTESY OF THE U.S. GEOLOGICAL SURVEY

QUADRANGLES INCLUDE: CRYSTAL MOUNTAIN, CO (1/1/1980) and BUCKHORN

MOUNTAIN, CO (1977).

SITE LOCATION MAP

CR 44H Structures Approx. 5 miles of CR 44H from Ballard Road east towards CR 27

Larimer County, Colorado

1901 Sharp Point Drive Suite C

Ft. Collins, Colorado 80525

20155038

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

Project Manager:

Drawn by:

Checked by: Approved by:

Project No.

File Name: Date:

A-1

Exhibit

1”=24,000 SF Scale:

MRA

EDB

EDB

BCR

10/26/2015

EXPLORATION PLAN



20155038 AERIAL PHOTOGRAPHY PROVIDED BY MICROSOFT BING MAPS


Larimer County, Colorado DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-2

Exhibit

EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-3

Exhibit

Structure 1

Structure 2

Structure 1

Structure 3

Structure 1

EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-4

Exhibit

Structure 4

Structure 1

Structure 5

Structure 1

EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-5

Exhibit

Structure 6

Structure 1

Structure 7

Structure 1

EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-6

Exhibit

Structure 8

Structure 4

Structure 1 Structure 4


Structure 9

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-7

Exhibit

Structure 10

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-8

Exhibit

Structure 11

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-9

Exhibit

Structure 12

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-10

Exhibit

Structure 13

Structure 4



Structure 14

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-11

Exhibit

Structure 15

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-12

Exhibit

Structure 16

Structure 4



EXPLORATION PLAN






PURPOSES

Project Manager:

Drawn by:


MRA

EDB

EDB

BCR

10/26/2015

Scale:

Project No.

File Name: Date:

AS SHOWN A-13

Exhibit

Structure 17

Structure 4




Responsive ■ Resourceful ■ Reliable Exhibit A-14

Field Exploration Description

The locations of borings were based upon the location of proposed structures provided by the

Client. Elevation of the ground surface for Boring Nos. 1 through 22 were interpolated from

topographic maps provided to us by the Client. The borings were located in the field by

measuring from existing site features.

The borings were drilled with a CME-75 truck-mounted rotary drill rig with solid-stem augers.

During the drilling operations, lithologic logs of the borings were recorded by the field engineer.

Disturbed samples were obtained at selected intervals utilizing a 2-inch outside diameter split-

spoon sampler. Penetration resistance values were recorded in a manner similar to the

standard penetration test (SPT). This test consists of driving the sampler into the ground with a

140-pound hammer free-falling through a distance of 30 inches. The number of blows required

to advance the standard split-spoon 18 inches (final 12 inches are recorded) or the interval

indicated, is recorded as a standard penetration resistance value (N-value). The blow count

values are indicated on the boring logs at the respective sample depths.

A CME automatic SPT hammer was used to advance the samplers in the borings performed on

this site. A greater efficiency is typically achieved with the automatic hammer compared to the

conventional safety hammer operated with a cathead and rope. Published correlations between

the SPT values and soil properties are based on the lower efficiency cathead and rope method.

This higher efficiency affects the standard penetration resistance blow count value by increasing

the penetration per hammer blow over what would be obtained using the cathead and rope

method. The effect of the automatic hammer's efficiency has been considered in the interpretation

and analysis of the subsurface information for this report.

The standard penetration test provides a reasonable indication of the in-place density of sandy

type materials, but only provides an indication of the relative stiffness of cohesive materials

since the blow count in these soils may be affected by the moisture content of the soil. In

addition, considerable care should be exercised in interpreting the N-values in gravelly soils,

particularly where the size of the gravel particle exceeds the inside diameter of the sampler.

Groundwater measurements were obtained in the borings at the time of site exploration. After

completion of drilling, the borings were backfilled with auger cuttings. Some settlement of the

backfill and/or patch may occur and should be repaired as soon as possible.

12

10

13

8

14

17

NP

8025.5

80058004.5

7-6-5N=11

4-4-5N=9

17-15-19N=34

10-7-11N=18

22-50/6"

0.5

21.021.5

GRAVEL SURFACING, about 6 inchesSILTY SAND WITH GRAVEL (SM), trace cobbles, fine to coarse grained, grayto brown, loose to very dense

BEDROCK, very hardBoring Terminated at 21.5 Feet

Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.

GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15

Approx. 5 miles on CR44H from Ballard Road east toward CR 27 Larimer County, ColoradoSITE:

Page 1 of 1

Advancement Method:4-inch solid flight auger

Abandonment Method:Borings backfilled with soil cuttings upon completion.

1901 Sharp Point Drive, Suite CFort Collins, Colorado

Notes:

Project No.: 20155038

Drill Rig: CME-75

Boring Started: 8/19/2015

BORING LOG NO. 1AVI PCCLIENT:Fort Collins, CO

Driller: Drilling Engineers, Inc.

Boring Completed: 8/19/2015

Exhibit: A-15

See Exhibit A-3 for description of field procedures.

See Appendix B for description of laboratoryprocedures and additional data (if any).

See Appendix C for explanation of symbols andabbreviations.

PROJECT: CR44H Structures

PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS

LL-PL-PISurface Elev.: 8026 (Ft.)

ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH

LOCATION See Exhibit A-2

Latitude: 40.572055° Longitude: -105.451864°

While drilling

WATER LEVEL OBSERVATIONS

11

14

9

13

15

8024.5

8016

8005.58005

4-3-4N=7

3-3-3N=6

9-12-21N=33

14-14-9N=23

50/5"

0.3

9.0

19.520.0

GRAVEL SURFACING, about 4 inchesFILL - SILTY SAND WITH GRAVEL , trace cobbles and boulders, dark brown,loose

SILTY SAND, trace gravel and cobbles, fine grained, gray to brown, mediumdense to very dense

large cobble

BEDROCK, very hardBoring Terminated at 20 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-16





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


8

19

39

7

4

11

NP

8012

8005

7993

7989.5

3-2-1N=3

1-6-7N=13

14-9-10N=19

19-38-12N=50

50/6"

0.2

7.0

19.0

22.5

GRAVEL SURFACING, about 2 inchesPOORLY GRADED SAND WITH SILT (SP-SM), trace cobbles, brown, blackand gray, very loose to medium dense

SILTY SAND WITH GRAVEL, trace cobbles and boulders, fine to mediumgrained, gray and olive, medium dense to very dense

SCHIST BEDROCK, gray to olive, very hard, slightly weathered

Auger refusal at 22.5 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-17





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

20

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


0

11

12

9

9

5

8009.5

8002

7999

7991.5

7990.5

4-3-3N=6

3-4-5N=9

16-25-40N=65

10-16-17N=33

50/4"

0.3

8.0

11.0

18.5

19.3

GRAVEL SURFACING, about 3 inchesSILTY SAND WITH GRAVEL, trace cobbles, fine grained, dark brown, loose

POORLY GRADED SAND WITH GRAVEL, coarse grained, yellow, very dense

SILTY SAND WITH GRAVEL, fine grained, dark brown, dense

BEDROCK, gray, very hard

Boring Terminated at 19.3 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-18





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


16

18

28

7

NP

7991

7990

4-4-2N=6

1-2-3N=5

19-17-16N=33

11.0

12.0

SILTY SAND, trace gravel, fine grained, brown to black

with cobbles, loose to dense

BEDROCK, very hard

Auger refusal at 12 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-19





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


10

13

6

7989

7988

5-6-4N=10

5-3-3N=6

12-32-23N=55

12.0

13.0

SILTY SAND WITH GRAVEL, olive to dark brown

trace cobbles, loose to very dense

BEDROCK, very hard



GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-20





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


5

0

18

14

8

7925.5

7924.5

8-10-14N=24

4-24-45N=69

7-13-28N=41

10-12-13N=25

50/6"

18.5

19.5

SILTY SAND WITH GRAVEL, trace cobbles and boulders, fine to mediumgrained, brown, medium dense to very dense

SCHIST BEDROCK, gray, very hard

Boring Terminated at 19.5 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-21





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


7

38

16 NP

7942.5

7937

7936

5-9-5N=14

3-5-6N=11

0.4

6.0

7.0

GRAVEL SURFACING, about 5 inchesPOORLY GRADED SAND WITH SILT AND GRAVEL (SP-SM), with cobblesand boulders, black, brown and reddish-brown, medium dense

BEDROCK, very hard



GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-22





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


3

8

13

8

0

NP

7991.5

7984

79757974.5

7-12-11N=23

5-6-7N=13

23-21-21N=42

50/1"

0.7

8.0

17.017.5

GRAVEL SURFACING, about 8 inches

SILTY SAND WITH GRAVEL, trace cobbles, fine grained, brown to gray,medium dense

POORLY GRADED GRAVEL WITH SAND, trace cobbles, fine to coarsegrained, brown, gray and black, dense to very dense

BEDROCK, very hardAuger refusal at 17.5 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-23





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


11

10

10

15

10

NP

7991

79777976.5

4-5-2N=7

2-1-1N=2

5-7-19N=26

29-37-33N=70

1.0

15.015.5


POORLY GRADED SAND WITH SILT AND GRAVEL, trace cobbles andboulders, fine to coarse grained, dark brown, very loose to medium dense

SCHIST BEDROCK, black and gray, hardBoring Terminated at 15.5 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-24





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

15

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


1

8

7

9 NP

7667

7659

7654.57654

5-7-7N=14

4-4-2N=6

10-10-9N=19

1.0

9.0

13.514.0


FILL - SILTY SAND WITH GRAVEL , trace cobbles, gray to brown, loose tomedium dense

POORLY GRADED GRAVEL WITH SAND (GP), with cobbles, olive and black,medium dense

BEDROCK, very hardAuger refusal at 14 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-25





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

10

FIE

LD T

ES

TR

ES

ULT

S

DEPTH



While drilling


4017

8

36-19-17

7664.5

7661

7659.57659

2-2-2N=4

4-3-4N=7

1.5

5.2

6.57.0


FILL - CLAYEY GRAVEL WITH SAND (GC), brown, loose

SILTY SAND WITH GRAVEL, fine to medium grained, reddish-brown

BEDROCK, very hardAuger refusal at 7 Feet


GR

AP

HIC

LO

G

TH

IS B

OR

ING

LO

G IS

NO

T V

ALI

D IF

SE

PA

RA

TE

D F

RO

M O

RIG

INA

L R

EP

OR

T.

GE

O S

MA

RT

LO

G-N

O W

ELL

201

550

38.G

PJ

TE

RR

AC

ON

2015

.GD

T 1

1/5

/15


Page 1 of 1




Notes:


Drill Rig: CME-75





Exhibit: A-26





PE

RC

EN

T F

INE

S

WA

TE

RC

ON

TE

NT

(%

)

ATTERBERGLIMITS


ELEVATION (Ft.)

SA

MP

LE T

YP

E

WA

TE

R L

EV

EL

OB

SE

RV

AT

ION

S

DE

PT

H (

Ft.)

5

FIE

LD T

ES

TR

ES

ULT

S

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