July 30, 2024 BET Project No. G23215

TO: Mr. Tem Fontaine, P.E.

Coastal Technology Corporation 3625 20th Street Vero Beach, Florida 32960

RE: Report of Geotechnical Data Beach Access Ramp Improvements Florida Shores Boulevard (Between S. Atlantic Ave and the Atlantic Ocean) Daytona Beach Shores, Volusia County, Florida

Dear Mr. Fontaine:

As requested, Bechtol Engineering and Testing, Inc. (BET) has completed geotechnical services relative to proposed improvements along Florida Shores Boulevard in Daytona Beach Shores, Florida. The purpose of BET's services was to evaluate physical and strength characteristics of subsurface materials encountered by test borings within the probable reconstruction area of a new/replacement paved roadway and beach access ramp, and within the probable construction area of a new/replacement sheet pile bulkhead, and based on these characteristics, to provide earthwork and pavement section related recommendations to aid in the design and construction of the proposed improvements, in addition to providing soil parameters for use in sheet pile and bulkhead design (by others)

Field Exploration BET’s field study, completed on June 10th and 11th of 2024, consisted of advancing two (2) Standard Penetration Test (SPT) borings (ASTM D1586) along the approximate alignment of the proposed seawall bulkhead, each to depth of 40 feet below existing ground surface. Additionally, BET advanced two (2) SPT borings along Florida Shores Boulevard within the existing beach access ramp, each to depth of 15 feet below existing ground surface. The SPT borings were supplemented by two (2) auger borings along the approximate location of the proposed return walls, each to depth of 10 feet below existing ground surface. Approximate locations of the borings are shown on the Boring Location Plan presented on the attached Figure 1.

Encountered subsurface conditions are presented in the form of Soil Profiles, shown on Figure 2.

Subsurface Conditions In general, the borings encountered between 2 to 5 feet of surficial deposits comprised of very loose to medium dense light gray to gray fine sands (Stratum 1), underlaid by medium dense to very dense light gray to light brown fine sands, with varying quantities of shell (Stratum 2), extending to depths ranging from 10 to

28.5 feet below the existing ground surface. Underlying soils to the deeper-seated SPT boring termination depths (TB-3 & TB-4) consisted of medium dense to dense gray slightly silty fine sands, with varying quantities of shell (Stratum 3).

BET notes that the SPT borings conducted within the existing beach access ramp area (TB-1 & TB-2) encountered a concrete pavement section at depths ranging from 2 to 4 feet below the existing ground surface and extending to depths ranging from 4.5 to 5.0 feet below the existing ground surface. Additionally, boring TB-4 encountered approximately 6 inches of asphalt fragments mixed within the Stratum 2 soils at a depth of approximately 4 feet below the existing ground surface. For a more in-depth soil stratification, please refer to the Soil Profiles presented on Figure 2.

Report of Geotechnical Data - Beach Access Ramp Improvements Florida Shores Boulevard (Between S. Atlantic Ave and the Atlantic Ocean), Daytona Beach Shores, Volusia County, Florida BET Project No. G23215 G23215 Report of Geotechnical Data.wpd

Groundwater Conditions Groundwater levels, as measured at the boring locations, were encountered at depths ranging from 2.1 to

7.9 feet below the ground surface existing at the time of drilling. In reference to approximate ground surface elevations at the boring locations, as interpolated from topographic data shown on the Conceptual Design Plan View, Sheet 2 prepared by Coastal Tech (dated 3/31/2023), the corresponding groundwater elevations at the time of drilling appeared to approximately be in the range of 1.5' to 4.2' North American Vertical Datum of 1988 (NAVD). Groundwater levels are subject to variation due to daily tidal fluctuations, seasonal climate changes and man induced influences. BET envisions that groundwater levels may temporarily rise to elevation 5' NAVD, or above, during wet seasons or periods of extreme high tides.

It should be noted that the estimated seasonal high groundwater levels should be considered accurate to approximately +/- 6 inches and do not provide any assurance that groundwater levels will not exceed these estimated levels during any given year in the future. Should surface water drainage be impeded, or should rainfall intensity, quantity and duration exceed the normally anticipated quantities, groundwater levels might exceed our seasonal high estimates. Furthermore, changes in the surface hydrology and subsurface drainage could have significant effects on the normal and seasonal high groundwater levels.

Soil Parameters (Seawall Bulkhead & Beach Access Ramp) Suggested soil parameters are tabulated on Figure 2 to aid the Design Engineer in the design and construction of the new seawall bulkhead structure.

For purposes of designing the beach access ramp and associated ramp foundations, pavement sections or other subsurface improvements, BET recommends the use of the following estimated soil parameters:

SOIL PARAMETER ASSUMED VALUE

Moist Unit Weight 110 PCF

Saturated Unit Weight 125 PCF

Submerged Unit Weight 60 PCF

Internal Friction Angle 30°

Active Earth Pressure Coefficient 0.33

Passive Earth Pressure Coefficient 3.00

At-Rest Earth Pressure Coefficient 0.50

Soil - Concrete Interface Friction Angle 20°

Subgrade Modulus 200 psi/in

Pavement Recommendations The borings conducted in proposed pavement reconstruction areas encountered subsurface soils consisted of fine sands (Strata 1 & 2). These soils appear to be relatively clean, stable granular materials which should be suitable for support of conventional asphalt and/or concrete pavement sections pending adequate completion of certain earthwork activities. Proposed finish pavement grades were not known at the time of this report, however BET envisions construction to be at or slightly above existing grades. Design vehicle loadings and frequencies were not known at the time of this report, but traffic is anticipated to consist of light-duty cars, pick-up trucks and vans, and occasional heavy-duty trucks or maintenance equipment. General Earthwork Recommendations are presented as Attachment A of this report. Pavement Section Recommendations are presented as Attachment B of this report.

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Florida Shores Boulevard (Between S. Atlantic Ave and the Atlantic Ocean), Daytona Beach Shores, Volusia County, Florida BET Project No. G23215 G23215 Report of Geotechnical Data.wpd

Limitations & Closure This report is prepared solely for the use of BET's client and their various design professionals as an aid in project design and preparation of project plans and documents. Evaluations and recommendations presented herein are based on limited subsurface data derived from test borings and without the knowledge of the specific improvements proposed. Subsurface conditions not disclosed by the borings performed may occur, and could influence construction of proposed improvements. Varying developmental schemes may alter the applicability of the evaluations and recommendations presented herein. Final design criteria, including foundation and grading plans, and vehicle loading and frequency criteria should be reviewed by BET in order that they may evaluate the applicability of their recommendations, and provide revised or additional recommendations as may be warranted.

BET appreciates the opportunity to be of service, and trusts this report is sufficient for your immediate needs.

If you should have any questions, or whenever BET may be of further service, please do not hesitate to call.

Respectfully, Bechtol Engineering and Testing, Inc.

Love B. Patel, P.E.

Senior Geotechnical Engineer Love B. Patel, P.E., State of Florida Professional Engineer, License No. 90753 This item has been digitally signed and sealed by Love B. Patel, P.E. on the date adjacent to the seal. Printed copies of this document are not considered signed and sealed, and the signature must be verified on any electronic copies.

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TB-1 TB-2

TB-4

TB-3

AB-2

AB-1

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BORING LOCATION PLAN

SCALE: 1" = 20'

APPROXIMATE LOCATION OF STANDARD PENETRATION

TEST BORING

APPROXIMATE LOCATION OF AUGER BORING

SYMBOL LEGEND

SCALE (feet)

0 105 20

FLORIDA SHORES BOULEVARD R

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60.6

45.6

66.0

0.0' TO 2.0'

DEPTH

MODULUS OF

SUBGRADE - K

(pci)

SUGGESTED SOIL PARAMETERS - BULKHEAD

30.1

37.9

COHESION - c (ksf)

0.00

0.00

NA

STRAIN AT 50%

STRESS - e50

(in./in.)

NA93.4

15.2

UNIT WEIGHT -

Ɣ (pcf)

FRICTION

ANGLE - Φ

(degrees)

39.7 0.00 NA146.4

RELATIVE

DENSITY

65.00

21.32

82.66

2.0' TO 5.0'

5.0' TO 7.0'

74.5 42.1 0.00 NA197.2 95.947.0' TO 8.0'

AT REST

EARTH

PRESSURE K0

0.33

ACTIVE

EARTH

PRESSURE KA

0.240.39

0.50

0.220.36

PASSIVE

EARTH

PRESSURE KP

4.18

3.01

4.53

0.200.33 5.06

65.0 39.5 0.00 NA139.4 80.608.0' TO 24.0'

60.6 37.9 0.00 NA93.4 65.0024.0' TO 34.0'

0.220.36 4.49

0.240.39 4.18

55.7 34.5 0.00 NA45.2 42.5834.0' TO 39.0' 0.280.43 3.61

59.9 37.3 0.00 NA80.0 59.6039.0' TO 40.0' 0.250.39 4.07

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SOIL PROFILES

VERTICAL SCALE: 1" = 10'

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CONCRETE

CONCRETE

ASPHALT

TB-1 TB-2 TB-3 TB-4 AB-1 AB-2

SOIL & SYMBOL LEGEND

LIGHT GRAY TO GRAY FINE SAND, (SP), VERY LOOSE TO

MEDIUM DENSE

LIGHT GRAY TO LIGHT BROWN FINE SAND, WITH VARYING

QUANTITES OF SHELL, (SP), MEDIUM DENSE TO VERY

DENSE

GRAY SLIGHTLY SILTY FINE SAND, WITH VARYING

QUANTITES OF SHELL, (SP-SM), MEDIUM DENSE TO

DENSE

UNIFIED SOIL CLASSIFICATION GROUP SYMBOL AS

DETERMINED BY VISUAL EXAMINATION

GROUNDWATER LEVEL, REFERENCED IN FEET TO

EXISTING GROUND SURFACE, DATE OF READING

STANDARD PENETRATION RESISTANCE IN BLOWS PER

FOOT

BORING HAND-AUGERED AT THIS DEPTH

NUMBER OF BLOWS (50) REQUIRED TO DRIVE SAMPLING

SPOON / INCHES DRIVEN (5)

N

(SP)

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RAMP BULKHEAD

*NOTE

RETURN WALL

ELEVATIONS BASED ON INTERPOLATION OF GROUND SURFACE

ELEVATION AT BORING LOCATIONS FROM TOPOGRAPHIC DATA

SHOWN ON THE FLORIDA SHORES BLVD CONCEPTUAL DESIGN

PLAN VIEW (DATED 3/31/23) PREPARED BY COASTAL TECH.

ACTUAL ELEVATIONS MAY VARY.

Florida Shores Boulevard (Between S. Atlantic Ave and the Atlantic Ocean), Daytona Beach Shores, Volusia County, Florida BET Project No. G23215 G23215 Report of Geotechnical Data.wpd

APPENDIX A

GENERAL EARTHWORK RECOMMENDATIONS

1.0 CLEARING/GRUBBING

1.1 Pavement areas, plus suitable margins, should be cleared and stripped of all surface vegetation, organic topsoils, existing structural improvements, and any other deleterious materials which may be encountered.

1.2 Tree removal should include the extraction of stumps and associated root network.

2.0 SUBGRADE SOILS COMPACTION

2.1 Exposed subgrade soils in cleared and stripped pavement areas should be wetted as needed to achieve near-optimum soil moisture conditions, and compacted to the degree and depth recommended below.

2.2 Recommended degree of subgrade soils compaction is 95% of the material’s theoretical maximum dry density, as determined by Modified Proctor Test (ASTM D-1557, AASHTO T-180).

2.3 Recommended depth of subgrade soils compaction in pavement areas is 12 inches.

3.0 FILL MATERIAL PLACEMENT AND COMPACTION

3.1 Where applicable, fill soils utilized to raise pavement areas to desired grade should consist of clean, granular materials with less than 15% passing No. 200 U.S. Standard Sieve.

3.2 Fill soils should be spread in loose lifts not exceeding 16 inches if compacted with heavy compaction equipment, or eight inches if compacted with light weight hand operated equipment.

3.3 Each successive lift should be wetted as needed to achieve near-optimum soil moisture conditions and compacted by appropriate mechanical means to the degree recommended below.

3.4 Recommended degree of fill soils compaction is 95% of the material’s theoretical maximum dry density, as determined by Modified Proctor Test (ASTM D-1557, AASHTO T-180).

4.0 COMPACTION TESTING

4.1 The recommended depth and degree of compaction for subgrade and fill soils should be verified by in-place density tests conducted in general conformance with appropriate ASTM density testing procedures.

4.2 Density tests should be conducted for each foot of compacted thickness at each test location.

4.3 Recommended minimum frequency of in-place density testing is one location per every 250 square feet of pavement area. Appropriate frequency of testing may vary depending upon construction procedures.

5.0 SPECIAL CONSIDERATIONS

5.1 Pavement areas should be wetted and proof-rolled prior to construction of pavement section in order to re-compact surface materials which may have become disturbed by utility installations and other construction activities.

5.3 The site contractor should be aware of nearby structures, and use vibratory compaction equipment with appropriate discretion.

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Florida Shores Boulevard (Between S. Atlantic Ave and the Atlantic Ocean), Daytona Beach Shores, Volusia County, Florida BET Project No. G23215 G23215 Report of Geotechnical Data.wpd

APPENDIX B

PAVEMENT SECTION RECOMMENDATIONS

1.0 ASPHALT PAVEMENT

1.1 Surface Course

Surface course should consist of a minimum of two inches (compacted thickness) in heavy-duty truck marshaling and main drive areas, and a minimum of 1.5 inches (compacted thickness) in light duty parking areas of asphalt conforming to FDOT specifications for Superpave 12.5 mm or 9.5 mm traffic level “C” asphaltic concrete.

1.2 Base Course

1.2.1 Limerock: Base course should consist of a minimum of eight inches (compacted thickness) in heavy-duty truck marshaling and main drive areas, and six inches (compacted thickness) in light duty parking areas, of limerock compacted to minimum relative compaction of 98% of the material’s Modified Proctor (ASTM D-1557, AASHTO T-180) laboratory maximum dry density. If limerock base is desirable, it is recommended that lowest finish pavement grade be set a minimum of 24 inches above estimated average seasonal high groundwater level.

1.2.2 Crushed Concrete: Base course should consist of a minimum of eight inches (compacted thickness) in heavy-duty truck marshaling and main drive areas, and six inches (compacted thickness) in light duty parking areas of crushed concrete (minimum LBR 100) compacted to minimum relative compaction of 98% of the material's Modified Proctor (ASTM D-1557, AASHTO T-180) laboratory maximum dry density.

1.3 Stabilized Subgrade

Subbase should consist of a minimum of eight inches (compacted thickness) in heavy-duty truck marshaling and main drive areas, and six inches (compacted thickness) in light duty parking areas, of granular fill or native soils mixed with a quantity of suitable stabilization material sufficient to achieve a minimum Limerock Bearing Ratio of 40% (LBR 40). Subbase should be compacted to minimum relative compaction of 98% of the material's Modified Proctor (ASTM D-1 557, AASHTO T-1 80) laboratory maximum dry density.

2.0 CONCRETE PAVEMENT

2.1 Surface Course

Surface course should consist of a minimum of eight inches (8") in heavy-duty truck marshaling areas, and six inches (6") in light duty parking areas, of concrete with a minimum 28-day compressive strength of 4,000 pounds per square inch (psi). Construction and contraction joints should be provided in general conformance to PCA guidelines.

2.2 Stabilized Subgrade

Subgrade should consist of a minimum of 12-inches (compacted thickness) of granular fill or native soils mixed with a quantity of suitable stabilization material sufficient to achieve a minimum Limerock Bearing Ratio of 30% (LBR 30). Subgrade should be compacted to minimum relative compaction of 95% of the material's Modified Proctor (ASTM 0-1557, AASHTO T-180) laboratory maximum dry density.

Actual design pavement section should be determined by a licensed Civil Engineer based on design vehicle loadings and frequencies.

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