12-CHRI_217021-244555_Final_Geotechnical_Report_Jaca-Sierra_07-17-18.pdf

FINAL - GEOTECHNICAL REPORT

ON THE EXPLORATION PERFORMED AT

THE SITE OF THE PROPOSED WHARF

BULKHEAD REPLACEMENT AT

CHRISTIANSTED, ST. CROIX, USVI

Submitted to:

HDR Inc.

Eng. Josiah M. Berg

Prepared by:

Manuel E. Candelario Cosme, MSCE, PE Carlos R. Sierra Del Llano, MSCE, PE

Date:

July 13, 2018

Job No. 7846

This report contains 71 pages including cover

J a c a & S i e r r a T e s t i n g L a b o r a t o r i e s P O B o x 3 6 3 1 1 6 , S a n J u a n , P R 0 0 9 3 6 - 3 1 1 6

R o a d 8 5 0 K m 0 . 2 L a s C u e v a s W a r d , T r u j i l l o A l t o , P R 0 0 9 7 6 7 8 7 - 7 6 1 - 2 5 7 0 7 8 7 - 7 4 8 - 6 9 7 0 w w w . j a c a s i e r r a . c o m

Table of Contents

1.0 INTRODUCTION:

2.0 FIELD WORK:

3.0 SUBSOIL GENERALIZED CONDITIONS: ................................................. 4 3.1 Site Geology: ................................................................................................................................................................. 4 3.2 Stratigraphy:................................................................................................................................................................. 5 3.3 Groundwater: ............................................................................................................................................................... 7 3.4 Seismic Classification:

4.0 RESULTS AND RECOMMENDATIONS: ................................................... 8 4.1 Case 1 - Deep Bedrock (≈30 feet): ....................................................................................................................... 9 4.2 Case 2 - Intermediate Bedrock Depth (≈15 feet): ....................................................................................... 10 4.3 Case 3 - Shallow Bedrock (≈5 feet): .................................................................................................................. 13 4.4 Pre-Drilling: ................................................................................................................................................................ 15 4.5 Vibration Effects Assessment and Monitoring: ............................................................................................ 16 4.6 Seismic liquefaction Analysis:

5.0 ADDITIONAL COMMENTS:

Page 2 of 20 – Job no. 7846 Wharf Bulkhead Replacement, St. Croix, USVI

GEOTECHNICAL REPORT

ON THE EXPLORATION PERFORMED AT

THE SITE OF THE PROPOSED WHARF

BULKHEAD REPLACEMENT AT

CHRISTIANSTED, ST. CROIX, USVI

1.0 INTRODUCTION:

The present geotechnical report covers the results of the exploration conducted at the National Historic Site at Christiansted, St. Croix, as part of the Wharf Bulkhead

Replacement Project.

Figure 1: Project Site Location, Christiansted, St. Croix, USVI

Jaca & Sierra Engineering, PSC was contracted by HDR Inc., to perform site subsoil investigations and provide geotechnical recommendations for the project. The

Site Location

Page 3 of 20 – Job no. 7846 exploratory program was directed to obtain subsurface soil information to be utilized in the formulation of the pertinent recommendations for the intended structure's foundation system.

This report has been prepared for the exclusive use of the owner, their architects, engineers and others involved in the preparation of the plans and specifications for the project.

2.0 FIELD WORK:

The field exploration consisted of drilling a total of ten (10) test borings project site. Three (3) borings were performed on the “waterside” on a balcony placed offshore towards the seaside of the existing bulkhead, while the remaining seven (7) borings were performed on the landside at an approximate distance of 8 to 50 ft from the sea-wall. The borings were drilled to a depth of 40 to 80 ft below existing ground surface (B.E.G.S.).

In situ testing and soil sampling was achieved by means of the universally adopted Standard Penetration Test (SPT) and split spoon sampler method according to

ASTM D 1586. Subsurface drilling was executed by means of the power auger method as per ASTM D 1452 using CME-55 drill rig to drive a 2.25 inches ID helical auger into

JBERG

Snapshot

Page 4 of 20 – Job no. 7846 the ground. A Casing Advancer NQ system was also used for drilling offshore

(“waterside borings”) and rock coring as per ASTM D 5872 using CME-55 drill rig.

Collected soil samples throughout the investigation were delivered to our laboratory to perform analyses of moisture content, unconfined compressive strength, soil classifications, direct shear, and rock compressive strength tests. The data collected was eventually used to formulate the engineering recommendations provided in this report.

3.0 SUBSOIL GENERALIZED CONDITIONS:

3.1 Site Geology:

The specific geology for the project site is governed by the Mount Eagle Group

(Km) as shown on the geology map of St. Croix1 in Figure 2 developed by the U.S.

Geological Survey. The Km formation is a diverge assemblage of deep-water volcaniclastics, tuffaceous sandstones, pelagic sediments, and gabbroic and dioritic intrusives. This formation is also characterized by well-lithified cretaceous rocks governs most of the site. The upper strata were mostly composed of saprolitic material described as clayey silt with sand derived from weathering of the underlying rock formation.

1 Robert A. Penken, [et al.] Geology and Hydrogeology of the Caribbean islands aquifer system of the Commonwealth of Puerto Rico and the U.S. Virgin Islands.

Page 5 of 20 – Job no. 7846

Figure 2: USGS Geology Map of St. Croix, USVI

3.2 Stratigraphy:

The subsurface profile generally consists of a fill layer followed by a clayey strata transitioning towards a saprolitic material and weathered rock. The soil stratigraphy is described as follows:

Fill: The upper fill layer varies in thickness from 3 to 14 feet. Generally, the fill layer thickness decreases towards the east side of the site,were rock was encountered at shallower depths. The material varied in composition from silty-sand-some-gravel to gravel-with-clayey-sand. Traces of organic matter and coral fragments were found on some soil samples within the upper 0-4 ft of fill as in boring LB-1. Standard Penetration

Test (SPT) "N" values varied between 2 to 52 bpf (blows per foot) for a very loose to very dense relative density.

Site Location

Page 6 of 20 – Job no. 7846

Clayey silt: The fill layer was followed by a fine-grained layer described as clayey silt with sand or as sandy clay. SPT "N" values were between 3 to 64bpf for a soft to hard consistency. The stratum extended to an approximate depth of 10 to 40 ft where it transitions to saprolitic material.

Saprolite: The clayey stratum transitions to a stiff saprolitic material showing high SPT “N” values in the order of 26 bpf to refusal values (N> 50 blows per 6 inches of penetration). The soil samples varied in composition from rock fragments with clayey sand to clay with gravelly sand.

Weathered Rock: The saprolite material transitions to weathered rock of the

Mount Eagle Group formation, which is characterized by volcaniclastics, tuffaceous sandstones. The cored samples were described as siltstones of weak to medium strength and highly to severely weathered. The rock horizon was met at depths varying between

6 to >80 ft below surface. To the east side of the site, rock was met at 6 ft, while it was not encountered at the drilled depth of 80 ft at the west side.

The above description corresponds to general observations from the obtained data and information of visual/manual inspection of the retrieved soil samples. For a detailed description of the soil boring profile refer to the enclosed boring logs in

Appendix B.

Page 7 of 20 – Job no. 7846

3.3 Groundwater:

After conclusion of the subsoil exploration, groundwater was found to vary between 4 to 6 ft beneath existing ground surface. Groundwater levels are expected to vary with tidal fluctuations or after prolonged rain events.

3.4 Seismic Classification:

In order to generate the values necessary to plot the Seismic Design Response

Spectrum, the American Society of Civil Engineers (ASCE 7-10) Standard for Minimum

Design Loads for Buildings and Other Structures was used to determine the design spectral response accelerations both for 0.2 and 1 second periods (SDS and SD1).

According to the analysis of the relative ground density based on the SPT “N” values, the site classification is of type “D”. This classification corresponds to a stiff soil.

The design parameters corresponding to the site coordinates were then determined:

• Mapped spectral response acceleration at short period, = 0.821;

• Mapped spectral response acceleration at a one (1) second period, = 0.306;

• Five-percent damped design spectral response acceleration at a short (0.2 sec.)

period, SDS = 0.641;

• Five-percent damped design spectral response acceleration at a one (1) second period, SD1 = 0.365;

• Peak Ground Acceleration, PGA = 0.352.

• PGAM = 0.404.

Page 8 of 20 – Job no. 7846

4.0 RESULTS AND RECOMMENDATIONS:

Based on the information obtained throughout our exploratory program, three main soil profiles were uncovered, as illustrated in the figure below. These conditions are identified as follows:

• Case 1 (deep bedrock): Area covered by borings LB-1, LB-2, LB-9, LB-10, WB-5 and WB-6. Soil profile characterized by hard saprolite with SPT “N” refusal values at approximately 29 to 34 ft below existing ground surface. The new bulkhead within this area may consist of an NZ section or equivalent vibrated and driven to the depth required per design. It is our opinion that this section can be designed as cantilever to intrusion on land that would bring upon if considering an anchored section.

• Case 2 (intermediate depth to bedrock): Area covered by borings LB-3 and LB-

8. Soil profile characterized by hard saprolite SPT “N” refusal values at approximately 10 to 14 ft below existing ground surface. On account of limitations of embedment penetration of the sheet pile section, two options are provided: 1)pre drill NZ type sheet pile wall to design depth or 2) consider a pipe Z combined wall section with the pipes having drill rock socket to achieve embedment on the rock. Case 2 area is to be considered as transition zone between case 1 and case 2 conditions.

• Case 3 (shallow bedrock): Area covered by borings LB-4 and WB-7. Soil profile characterized by weathered rock at approximately 3 to 6 ft below existing ground surface. The case 3 recommendations are similar to those described for case 2 scenario with the difference that the fractured rock is exposed at or near mudline surface. Either entirely pre-drilled Z sections or Pipe Z combined walls with rock sockets are technical feasible options.

Page 9 of 20 – Job no. 7846

Figure 3: Schematic of the approximate extent of the three identified soil profiles

The following subsections present the soil stratigraphy for each of the identified cases with the respective soil strength parameters and considerations for sheet pile design.

4.1 Case 1 - Deep Bedrock (≈30 feet):

Case 1 represents the soil stratigraphy uncovered by borings LB-1, LB-2, LB-

9,LB-10, WB-5 and WB-6, which is characterized by a fill layer, followed by medium clay and hard saprolite. The soil profile is presented below, along with the respective soil strength parameters for the uncovered strata.

Case 1 Case 2

Case 3

LB-1

WB-6

WB-5

WB-7

LB-4

LB-8

LB-3

LB-9

LB-2LB-10

Page 10 of 20 – Job no. 7846

Table 1: Case 1 - Soil Strength Parameters (long-term drained condition)

Soil Type Approx. Depth Below Ground

Surface (ft)

*Approx.

Elevation Below Sea Level (ft)

Angle of Internal

Friction, Ø (˚)

Effective Unit

Weight, γ (pcf)

Cohesion, c (psf) p-y Modul usk (lb/in3) cyclic

Strain Factor, ε50

Fill:

gravelly sand some clay

0 – 10 +3.20 to -6.80

30 35 50** 20 -

Soft Sandy Clay 10 - 20 -6.8 to -16.8 28 40 0 20 0.005

Stiff Clayey Silt 20 - 30 -16.8 to

-26.8 30 60 200 400 0.0005

Saprolite /Weathered

Rock 30 + -26.8 + 35 75 1000 - -

*Elevations vary by boring. These are provided in Boring Logs (see Appendix B).

**Cohesion value is provided in consideration of the contribution of the existing wall soil supporting elements that will remain buried behind the new wall.

It is understood that the project are considering use of an NZ type sections in cantilever. It is our opinion, that these regular Z type sections are a viable option. The sheet piles will need to be vibrated thru upper loose sediments and driven to design depth or refusal thru the stiff clayey saprolites and highly weathered rock formations.

4.2 Case 2 - Intermediate Bedrock Depth (≈15 feet):

Case 2 represents the soil stratigraphy uncovered by borings LB-3 and LB-8, which is characterized by a sandy layer followed by hard saprolite at approximately 15 feet of depth below ground surface. The soil profile is presented below, along with the respective soil strength parameters for the uncovered strata.

Page 11 of 20 – Job no. 7846

Table 2: Case 2 - Soil Strength Parameters (long-term condition)

Approx. Depth Below Ground

Surface (ft)

*Approx.

Elevation Below Sea Level (ft)

Angle of Internal

Friction, Ø

Effective Unit

Weight, γ (pcf)

Cohesion, c (psf) p-y Modulus, k

(lb/in3) cyclic

Strain Factor, ε50

Fill:

gravelly sand some clay

0 – 10 +2.75 to -7.25

30 35 100** 20 -

Sand 10-15 -7.25 to -12.25 32 60 0 80 -

Weathered Rock 15+ -12.25 + 45 80 500 0.00005

*Elevations vary by boring. These are provided in Boring Logs (see Appendix B).

This bulkhead along this area will have limitations on drivability for Z type sheet pile sections.It is estimated that sheet pile sections could be driven to depths of 15 to 20

ft. Pre-drilling will be required for case 2 and case 3 area to allow installation of each section to that depth required per design. However, it is important to consider that any pre-drilling on this site will be complicated and limited due to the stringent environmental requirements. Therefore, drilling thru the interior of a pile or casing would help control sediment spread during drilling process. In that regard, the feasibility of pre-drilling must be evaluated in light of how it will be performed without causing a major spread of sediment on the water even with the provision of turbidity barriers. Pre-drilling can be achieved thru the interior of a temporary casing, which is

Page 12 of 20 – Job no. 7846 then extracted and used in the subsequent drill holes. This process will need to be done for each sheet pile element.

Another concept that could be implemented for the project is to use composite section for the Pipe-Z elements where the pile is driven (or drill and drive) thru a certain depth, then drilling is performed thru the pile interior to form a rock socket that is then filled with tremie concrete up to the top of the pile. The advantage of this concept over pre-drilling is that it will require less drilling; but the disadvantage may be related to material costs.

The backfill between the new wall and the existing could consist of either ¾ inch down gravel or flowable lean concrete poured by tremie method. The tremie consists of pour the flowable concrete with a pipe that is placed at the bottom of the area to be filled and the concrete is pumped in such way that it displaces the overlying water until clean concrete is observed at the top. This method, if properly implemented provides an improved assurance that this space is filled and integrates better existing and the new. The herein provided earth pressure parameters assume a gravel backfill.

Page 13 of 20 – Job no. 7846

Figure 4: Schematic of Pipe Z section with drilled and grouted rock socket alternative

4.3 Case 3 - Shallow Bedrock (≈5 feet):

Case 2 represents the soil stratigraphy uncovered by borings LB-4 and WB-7, which is characterized by a fill layer followed by rock at approximately 5 feet of depth below ground surface. The soil profile is presented below, along with the respective soil strength parameters for the uncovered strata.

Page 14 of 20 – Job no. 7846

Table 3: Case 3 - Soil Strength Parameters

Approx.

Depth Below

Ground Surface (ft)

*Approx.

Elevation Below Sea Level (ft)

Angle of Internal

Friction, Ø

Effective Unit

Weight, γ (pcf)

Cohesion, c (psf) p-y Modulus, k (lb/in3) cyclic Fill: gravelly sand some clay 0 – 5 +3.3 to -1.7 30 35 100** 20

Weathered Rock 5-10 -1.7 to -6.7 45 70 500 -

Rock 10 + -6.7 + 80 10,000

*Elevations vary by boring. These are provided in Boring Logs (see Appendix B).

For these conditions, having shallow fractured rock near mudline, pre-drilling will be required. Similar recommendation as those provided for case 2 will be applicable. For this case all sheet piles sections will need to be pre-drilled to their design embedment length or use a Pipe-Z composite section with a bottom drilled rock socket.

A third alternative that could be evaluated for these shallow bedrock conditions is to provide a shoreline revetment consisting of precast concrete blocks, rip rap or combinations. Any of this concepts deviates significantly from current plans and would require separate assessment beyond current scope of works.

Page 15 of 20 – Job no. 7846

Figure 5: Schematic of Pipe Z section with drilled and grouted rock socket

4.4 Pre-Drilling:

The rock was found to be, in most cases, closely fractured with medium strong rock particle strength (compressive strength between 3,000 to 6000 psi, RQD values less than 20). It is our opinion that drilling can be achieved with carbide bullet tip rock augers in combination with cleaning buckets to aid removing the rock fragments that loosen from the excavation sides.

Page 16 of 20 – Job no. 7846

Nevertheless, the specialty drilling contractor should evaluate conditions and use his judgement and experience to provide suitable sized drilling rig and tools to achieve required depth and diameter per design. As previously mentioned, due to environmental impact concerns, at temporary casing will be required to achieve drilling, among other methods of sedimentation and environmental controls.

4.5 Vibration Effects Assessment and Monitoring:

The vibration effects during the installation of the sheet pile walls shall be evaluated. This shall be accomplished by a four (4) step process as follows: 1) Pre-

Construction Survey; 2) Vibration Control Plan; 3) Field Vibration Monitoring during construction; and 4) Post Construction Survey.

• Pre-construction survey consists of an assessment made by vibration specialist or structural engineer to document vulnerabilities and collect photographic evidence of pre-construction conditions. This is important to have fair trial in case of a claim.

• Based on the pre-construction survey, a vibration monitoring and control plan is developed by a vibration specialist or geotechnical engineer. This analysis will include a determination of the site specific vibration thresholds (Peak Particle

Velocity) and establish risks based vibration control and monitoring. This report

Page 17 of 20 – Job no. 7846 shall include a plan for mitigation of vibrations if deemed necessary. These could include avoiding certain frequencies of vibrations, controlling impact energies. It is advisable to conduct a field test on safe locations, distant from risks, and determine the attenuation curves of ppv versus source distance, thus it could be foreshadowed of any problems in closer proximity to risks and plan beforehand on mitigation measures.

• Vibration monitoring during construction: These service shall consist of an onsite vibration control specialist with a minimum of two (2) seismographs placed at strategic locations. The specialist will monitor construction vibration and inform the owner or representative of any vibration magnitude (peak particle velocity/frequency) exceeding thresholds established in the plan.

• The post-construction survey shall be performed by same professional in charge of the pre-construction survey with the aim of documenting -before and after-conditions and log any damages that may have resulted from the construction activities.

4.6 Seismic liquefaction Analysis:

Liquefaction is a phenomenon that occurs when loose cohesionless soils below water level are subject to dynamic stresses to the point where excess water pressure in

Page 18 of 20 – Job no. 7846 between soil particles increase to a level that the seismic induced increase in water pressure exceed the effective stress and soils not having enough binding (cohesion) liquefy. The overall potential to liquefaction was confirmed using the PGA of 0.40g per

ASCE 7-10. A 7.0 magnitude earthquake was considered. Liquefaction analysis was made using the recent Idriss and Boulanger (2014) criteria for evaluation of liquefaction based on SPT N results. Liquefaction will manifest in the form of localized settlements, sand boils and lateral spreading of the ground. The following table presents the elevation where soils are expected to liquefy per boring location.

Table 4: Approximate Depth to Soil Liquefaction per Boring Location

Boring Elevation

(ft) Liquefaction

Potential

LB-1 -10 certain LB-2 -15 certain LB-3 -7 certain LB-4 - no liquefaction WB-5 -15 certain WB-6 -15 certain WB-7 - no liquefaction LB-8 -12 Moderate likelihood LB-9 -12 certain LB-10 -8 certain

Page 19 of 20 – Job no. 7846

5.0 ADDITIONAL COMMENTS:

It is recommended that this submitted geotechnical soil report be carefully studied and evaluated to coordinate those pertinent office meetings during the project design stage to discuss the various considered project design concepts and to clarify or include any other pertinent geotechnical design recommendations not covered in our report.

It is important to note that this report has been prepared for design purposes.

The project contractors must consult with geotechnical engineers in the development of planning and cost estimates for the project and conduct additional investigation and testing, if deemed necessary. We shall not be responsible for interpretations made by others on the information contained in this report.

Note that the herein given recommendations are based on test borings performed on spots, which are considered as representative of the subsoil conditions within the site. However, this fact does not guarantee that different conditions will not be found during construction progress or excavations. In such instances, we shall be notifiedto proceed with a field visual inspection directed to formulate the corresponding solution.

In the event that a new project design concept is different from that being considered in this report at the moment of the submittal of this report, it shall be

Page 20 of 20 – Job no. 7846 provided to us in order to fulfill a proper evaluation and include additional general design and construction recommendations.

We wish to thank you for the opportunity of submitting this geotechnical engineering report.

Cordially, JACA & SIERRA ENGINEERING, PSC

Manuel E. Candelario Cosme, MSCE, PE

Carlos R. Sierra Del Llano, MSCE, PE

Appendix A:

Boring Locations Plan

Boring Locations Plan

Wharf Bulkhead Replacement, Christiansted, STX, USVI

Appendix B:

Boring Logs

3.04

-0.96

-10.96

FILL: silty sand some clay and gravel trace organic matter (wood), medium, yellowish brown, dark brown

FILL: coral fragments and gravel with clayey sand, medium to dense, dark gray A-2-4 PI=9 Gravel: 50% Sand: 36% Fines: 14%

CLAYEY SILT with sand trace gravel, very stiff to medium, reddish yellow, yellowish brown, light gray, olive yellow A-7-6 PI=30 Gravel: 19% Sand: 29% Fines: 52%

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

SUBSURFACE EXPLORATION LOG

BORING No.: LB-1

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627803.521' N 1258121.8707' E DATE STARTED: 4-24-18 DATE COMPLETED: 4-24-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 3.04 GROUNDWATER (ft): Initial: 4 Final: 3.5 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 55.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

N-W

-30.96

-35.96

CLAYEY SAND some gravel, very dense, gray, brown, reddish yellow

SAPROLITE: sampled as clay with gravelly sand, very dense, reddish yellowish brown, gray

Do... sampled as rock fragments with sand some clay

S-9

S-10

S-11

S-12

S-13

S-14

50/5"

50/3"

50/5"

50/3"

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-1

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

3.28

1.28

-5.72

-15.72

-20.72

TOPSOIL: clayey silt with sand, very stiff, yellowish brown

FILL: gravel with sand some clay, medium to loose, dark gray, brown

SANDY CLAY some gravel, soft, gray

CLAYEY SILT some sand, very stiff, brownish yellow, light gray

CLAYEY SAND with rock fragments, medium, yellowish brown, light gray

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

SUBSURFACE EXPLORATION LOG

BORING No.: LB-2

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627756.681' N 1258302.6655' E DATE STARTED: 4-19-18 DATE COMPLETED: 4-19-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 3.28 GROUNDWATER (ft): Initial: 5 Final: 4 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 55.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

-25.72 29 SAPROLITE: sampled as clayey sand some rock fragments, gray, yellowish brown A-2-4 PI=10 Gravel: 7% Sand: 67% Fines: 26%

Do:... sampled as sand with rock fragments some clay, gray, yellowish brown

S-9

S-10

S-11

S-12

S-13

S-14

50/6"

50/6"

50/4"

40/6"

50/3"

40/3"

50/6"

50/6"

50/4"

40/6"

50/3"

40/3"

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-2

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

2.80

0.80

-7.20

TOPSOIL: clayey silt with sand some gravel, stiff, yellowish brown

FILL: gravel with sand some clay, loose, gray, yellowish brown A-2-4 PI=8 Gravel: 57% Sand: 31% Fines: 12%

SAPROLITE: sampled as rock fragments with sand some clay, gray, yellowish brown

A-2-4 PI=8

Gravel: 20% Sand: 60% Fines: 20%

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

50/3"

50/6"

50/4"

50/3"

50/6"

50/4"

SUBSURFACE EXPLORATION LOG

BORING No.: LB-3

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627827.0148' N 1258465.048' E DATE STARTED: 4-24-18 DATE COMPLETED: 4-24-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 2.8 GROUNDWATER (ft): Initial: 4 Final: 3.83 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 60.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

S-9

S-10

S-11

S-12

S-13

S-14

50/2"

50/6"

50/3

50/3"

50/2"

50/2"

50/2"

50/6"

50/3"

50/3"

50/2"

50/2"

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-3

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

S-15 50/1" 50/1" 13

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-3

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 3

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

3.29

1.29

0.29

-2.71

TOPSOIL: clayey silt with sand some gravel, stiff, yellowish brown

FILL: gravelly sand, medium, yellowish brown, gray

WEATHERED ROCK sampled as rock fragments some sand trace clay, gray, yellowish brown

SANDSTONE, weak to medium strong, highly to severely weathered, highly to intensely fractured, gray, yellowish brown rock compressive strength: 3,283 psi

S-1

S-2

S-3

HQ-4

50/4"

50/4"

50/3"

50/4"

50/4"

50/3"

83 7

SUBSURFACE EXPLORATION LOG

BORING No.: LB-4

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627810.8293' N 1258613.6502' E DATE STARTED: 4-11-18 DATE COMPLETED: 4-11-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 3.29 GROUNDWATER (ft): Initial: 4 Final: 3.83 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 11

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

4.00

0.00

-7.00

-15.00

Balcony deck 4 ft over sea level

Sea Level

SILTY SAND some gravel and shell fragments, very loose, dark gray

CLAYEY SILT with sand trace gravel, stiff to very stiff, reddish yellow, yellowish brown, light gray, olive, yellow

S-1

S-2

S-3

S-4

20 1.6

SUBSURFACE EXPLORATION LOG

BORING No.: WB-5

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627825.618' N 1258394.416' E DATE STARTED: 5-9-18 DATE COMPLETED: 5-9-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 4 GROUNDWATER (ft): Initial: Not Found Final: ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 60.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

-25.00 29 SAPROLITE: sampled as clayey silt with sand and rock fragments, gray, yellowish brown

Do... sampled as gravelly sand some clay

S-5

S-6

S-7

S-8

S-9

S-10

40/5"

40/4"

40/2"

40/2"

40/3"

40/1"

40/5"

40/4"

40/2"

40/2"

40/3"

40/1"

1.0

SUBSURFACE EXPLORATION LOG

BORING NUMBER: WB-5

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

S-11 40/3" 40/3" 7

SUBSURFACE EXPLORATION LOG

BORING NUMBER: WB-5

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 3

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

4.00

0.00

-10.00

-15.00

Balcony deck 4 ft over sea level

Sea Level

CLAYEY SAND with gravel, loose to medium, dark gray

CLAYEY SILT with sand some gravel, stiff, light gray, yellowish brown A-6 PI=18 Gravel: 7% Sand: 36% Fines: 57%

S-1

S-2

S-3

S-4

1.4

SUBSURFACE EXPLORATION LOG

BORING No.: WB-6

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627767.708' N 1258222.716' E DATE STARTED: 5-11-18 DATE COMPLETED: 5-11-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 4 GROUNDWATER (ft): Initial: Final: ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 60.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

-25.00 29 SAPROLITE: sampled as gravelly sand some clay, dense to very dense, yellowish brown, gray

A-2-4 PI=7

Gravel: 20% Sand: 57% Fines: 23%

S-5

S-6

S-7

S-8

S-9

S-10

50/2"

50/3"

50/3"

50/2"

50/2"

50/3"

50/3"

50/2"

SUBSURFACE EXPLORATION LOG

BORING NUMBER: WB-6

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

S-11 50/5" 50/5" 13

SUBSURFACE EXPLORATION LOG

BORING NUMBER: WB-6

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 3

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

4.00

0.00

-2.00

-5.00

Balcony deck 4 ft over sea level

Sea Level

HIGHLY WEATHERED ROCK sampled as rock fragments some sand

SANDSTONE, weak to medium strong, highly to severely weathered, highly to intensely fractured, gray, yellowish brown

S-1

HQ-2

50/2"

50/1" 50/1"

18 0

SUBSURFACE EXPLORATION LOG

BORING No.: WB-7

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627832.392' N 1258573.211' E DATE STARTED: 4-9-18 DATE COMPLETED: 4-9-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 4 GROUNDWATER (ft): Initial: Final: ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 14

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

2.69

0.69

-1.31

-3.31

-6.31

-11.31

-19.31

TOPSOIL: clayey silt with sand some gravel, very stiff, brown

FILL: clayey sand with gravel, loose, yellowish brown, gray

FILL: sandy clay some gravel, soft, gray, brown

SANDY CLAY some gravel, stiff, yellowish brown

SAND with gravel some clay, medium, yellowish brown A-2-4 PI=7 Gravel: 12% Sand: 63% Fines: 25%

SAPROLITE: sampled as sand with gravel some clay, yellowish brown, gray

SANDSTONE, weak to medium strong, highly to severely weathered, highly to intensely fractured, gray, yellowish brown

S-1

S-2

S-3

S-4

S-5

S-6

HQ-7

HQ-8

40/5"

50/1"

40/5"

50/1"

SUBSURFACE EXPLORATION LOG

BORING No.: LB-8

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627778.748' N 1258507.5163' E DATE STARTED: 4-20-18 DATE COMPLETED: 4-20-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 2.69 GROUNDWATER (ft): Initial: 5 Final: 4 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 29

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-8

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

3.30

1.30

-10.70

TOPSOIL: clayey silt with sand some gravel, very stiff, yellowish brown

FILL: sand with gravel some clay, very loose to loose, gray, brown

CLAYEY SILT with sand, very stiff to hard, yellowish brown, gray

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

SUBSURFACE EXPLORATION LOG

BORING No.: LB-9

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627780.7797' N 1258402.7888' E DATE STARTED: 4-19-18 DATE COMPLETED: 4-19-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 3.3 GROUNDWATER (ft): Initial: 5 Final: 4 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 45.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

-25.70

-42.20

SAPROLITE: sampled as clayey sand with rock fragments, gray, yellowish brown

45.5 SANDSTONE, weak to medium strong, highly to severely weathered, highly to intensely fractured, gray, yellowish brown

S-9

S-10

S-11

HQ12

40/3"

50/5"

50/5"

50/2"

40/3"

50/5"

50/5"

50/2"

20 0

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-9

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

3.17

1.17

-7.83

-14.83

TOPSOIL: clayey silt with sand some gravel, very stiff, brown

FILL: gravel with sand some clay, very dense to loose, gray, brown A-2-4 PI=7 Gravel: 40% Sand: 44% Fines: 16%

CLAYEY SILT with sand, very stiff, light gray, light yellowish brown

Do... trace sand, medium to very stiff

SAPROLITE: sampled as clayey silt with sand, and rock fragments, hard, yellowish brown, gray

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

S-9

S-10

S-11

S-12

S-13

S-14

SUBSURFACE EXPLORATION LOG

BORING No.: LB-10

PROJECT:

Wharf Bulkhead Replacement

JOB:

OF

SHEET 1

LOCATION: St. Croix DRILLER/DRILL RIG: Eduardo Santiago / CME-55 COORDINATES: 627725.8191' N 1258202.0765' E DATE STARTED: 4-12-18 DATE COMPLETED: 4-12-18

DESCRIPTION BY: Manuel Candelario SURFACE ELEVATION (ft): 3.17 GROUNDWATER (ft): Initial: 6 Final: 5 ENGINEER: Manuel Candelario DRILLING METHOD: Hollow-Stem Auger 2.25" ID TOTAL DEPTH (ft): 80.5

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

Do... sampled as clayey sand with rock fragments

S-15

S-16

S-17

S-18

S-19

S-24

S-25

S-26

S-27

S-28

S-29

S-30

S-31

S-32

S-33

S-34

50/6"

50/4"

50/3"

50/3"

50/3"

50/6"

50/6"

50/6"

50/6"

50/6"

50/3"

50/4"

50/6"

50/4"

50/3"

50/6"

50/6"

50/6"

50/6"

50/6"

50/3"

50/4"

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-10

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 2

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

Do... sampled as rock fragments, some sand, gray

S-35

S-36

S-37

S-38

S-39

S-40

S-41

S-42

S-43

S-44

50/3"

50/2"

50/6"

50/5"

50/2"

50/3"

50/3"

50/3"

50/2"

50/3"

50/3"

50/2"

50/6"

50/5"

50/2"

50/3"

50/3"

50/3"

50/2"

50/3"

SUBSURFACE EXPLORATION LOG

BORING NUMBER: LB-10

BORING LOG (CONT. SHEET)

PROJECT

Wharf Bulkhead Replacement

JOB

OF

SHEET 3

N W Qu

"N" - Number of blows required to drive the sampling spoon a distance of 12 in. with a 140 lbs hammer falling 30 in.

"W" - Natural Moisture Content in percentage of dry weight. Initial G.W. Depth "Qu" - Unconfined Compressive Strength in tons per square foot. Final G.W. Depth "Rc" - Core recovery in percent for each successive run. "RQD" - Rock quality designation.

"WH" - Sample was recovered by advancing the sampler with the weight of the hammer.

"P" - A "P" in the Unconfined Compressive Strength test indicates the use of the pocket Penetrometer.

ELEV

(ft)

0.00

DEPTH

(ft) DESCRIPTION

LE

G

E N

D

S A

M P

LE

N

O

TY

P

E

B

LO

W S

SPT

N

W Qu RC RQD%

20 40 60 80

1 2 3 4Qu

Appendix C:

Laboratory Tests Results

(X=NO)PERCENTFINERSIZE

PASS?SPEC.*PERCENTSIEVE

Project No:

Project:

Client:

Elev./Depth:Location:

Date:Source of Sample:Sample No.:

Remarks

Classification

Coefficients

Atterberg Limits

Material Description

AASHTO=USCS=

Cc=Cu=

D10=D15=D30=

D50=D60=D85=

PI=LL=PL=

Particle Size Distribution Report

P E R C E N T F

IN

E R

100 10 1 0.1 0.01 0.001500

GRAIN SIZE - mm

% COBBLES % GRAVEL % SAND % SILT % CLAY

i n i n i n

-1 /2 i n i n

/4 i n

/2 i n

/8 i n

0.0 49.7 35.9 14.4

Figure7846

Wharf Bulkhead Replacement-St. Croix, USVI

HDR, Inc.

4-9.5'St. Croix, USVI

5/24/18Project SiteLB-1

Tested by: L. Medina

Checked by: Manuel Candelario Cosme, MSCE, PE

A-2-4(0)GC

0.08690.822 4.678.0522.0

92819

Clayey gravel with sand

(no specification provided)

JACA & SIERRA

TESTING LABORATORIES

San Juan, Puerto Rico

100.0 94.6 76.7 66.1 62.6 50.3 39.3 24.0 17.4 14.4

1.5 in.

1 in.

.75 in.

.5 in.

.375 in.

#4

#10 #40

#100 #200

Project No:

Project:

Client:

Elev./Depth:Location:

Date:Source of Sample:Sample No.:

Remarks

Classification

Coefficients

Atterberg Limits

Material Description

AASHTO=USCS=

Cc=Cu=

D10=D15=D30=

D50=D60=D85=

PI=LL=PL=

Particle Size Distribution Report

P E R C E N T F

IN

E R

100 10 1 0.1 0.01 0.001500

GRAIN SIZE - mm

% COBBLES % GRAVEL % SAND % SILT % CLAY

i n i n i n

-1 /2 i n i n

/4 i n

/2 i n

/8 i n

0.0 19.0 28.5 52.5

Figure7846

Wharf Bulkhead Replacement-St. Croix, USVI

HDR, Inc.

14-20.5'St. Croix, USVI

5/24/18Project SiteLB-1

Tested by: L. Medina

Checked by: Manuel Candelario Cosme, MSCE, PE

A-7-6(11)CL

0.2348.65

304515

Sandy lean clay with gravel

(no specification provided)

JACA & SIERRA

TESTING LABORATORIES

San Juan, Puerto Rico

100.0 92.7 88.4 85.8 81.0 74.3 64.2 56.9 52.5

1 in.

.75 in.

.5 in.

.375 in.

#4

#10 #40

Project No:

Project:

Client:

E…