Appendix_6_-_Geotech_Report_-_MC2_2016.pdf

MC Squared, Inc.

Geotechnical Engineering Services Report

Mullet Creek Bank Restoration Pinellas County, Florida

Prepared for: CH2M Hill Engineers, Inc.

4350 W. Cypress St., Suite 600

Tampa, FL 33607

Prepared by: MC Squared, Inc.

5808-A Breckenridge Parkway Tampa, FL 33610

MC2 Project No. T101613.205 Date: August 2017

5808-A Breckenridge Parkway, Tampa, Florida 33610

Phone (813) 623-3399, Fax (813) 623-6636 www.mc2engineers.com

August 2, 2017 (revised November 3, 2017)

Mr. Rick Gorsira Sr. Environmental Scientist CH2M Hill Engineers, Inc.

4350 W. Cypress St., Suite 600 Tampa, FL 33607

Subject: Geotechnical Engineering Services Report

Pinellas County, Florida MC2 Project No. T101613.205

Dear Mr. Gorsira:

MC Squared, Inc. (MC2) has completed the geotechnical engineering services for the referenced project. This work was performed in general accordance with MC2 Proposal No. T101613.205 dated October 27, 2016 and revised on January 4, 2017. The results of this geotechnical exploration, together with our recommendations, are included in the accompanying report. This revision incorporates the comments made by your office on August 9, 2017

Often, because of design and construction details that occur on a project, questions arise concerning subsurface conditions. MC2 is pleased to continue our role as geotechnical consultants during the construction phase of the project.

We trust that this report will assist you in the evaluation and design of the slope stability measures at the project site. We appreciate the opportunity to be of service to you on this project. Should you have any questions, please do not hesitate to contact us.

Respectfully submitted, MC Squared, Inc.

Bradley Crowson, E.I. Jodonna Jimenez, P.E.

Staff Engineer Project Engineer Florida P.E. License No. 47701

Jeffery L. Hooks, P.E. Winston L. Stewart, P.E.

Project Manager Vice President Florida P.E. License No. 67882 Florida P.E. License No. 81643

Pinellas County, FL i

Table of Contents

1 PROJECT INFORMATION

1.1 PROJECT AUTHORIZATION

1.2 PROJECT DESCRIPTION

1.3 SCOPE OF WORK AND SERVICES

2 SITE CONDITIONS

2.1 SITE FEATURES

2.2 PINELLAS COUNTY SOIL SURVEY

2.3 TOPOGRAPHIC SURVEY

3 FIELD EXPLORATION PROGRAM

3.1 STANDARD PENETRATION TEST (SPT) BORINGS

3.2 PROCTOR AND FULL GRADATION SAMPLING

4 LABORATORY TESTING

5 SUBSURFACE CONDITIONS

5.1 SUBSURFACE SOIL AND GROUNDWATER CONDITIONS

6 OBSERVATIONS AND RECOMMENDATIONS

6.1 GENERAL

6.2 SITE EVALUATION

7 REHABILITATION

8 REPORT LIMITATIONS

APPENDIX

Soil Parameters – Table No. 2 Project Location Map - Sheet 1 Boring Location Map - Sheet 2 NRCS – USDA Soil Survey Map - Sheet 3 USGS Topographic Map - Sheet 4 Subsurface Boring Profiles - Sheet 5 Subsurface Boring Profile Legend - Sheet 6 Individual Soil Profiles – 4 Pages Modified Proctor Test – 1 Page Grain Size Distribution Test – 2 Pages Test Procedure

1 PROJECT INFORMATION

1.1 Project Authorization

Authorization to proceed with this project was issued by Patricia Elder of CH2M Hill Engineers, Inc. (CH2M) through a signed agreement on June 22, 2017.

1.2 Project Description

Project information was provided by Mr. Rick Gorsira and David Paiko of CH2M through e-mail and verbal communications and during multiple project site visits with MC2 personnel. Based on our understanding, the project requires geotechnical explorations to support the evaluation and design of slope stability measures along Mullet Creek, located east of McMullen Booth Road and north of Cedar Street in Pinellas County.

1.3 Scope of Work and Services

To achieve the project objective, our geotechnical exploration program consisted of the following services:

1. Conducting a visual reconnaissance of the project site, and reviewing the USDA Soil Survey for Pinellas County and the USGS topographic maps.

2. Clearing utilities in the vicinity of the proposed boring locations.

3. Performing a total of four (4) Standard Penetration Test (SPT) borings to a depth of fifteen below existing ground surface (BGS) along the top of the creek slope.

4. Collecting soil samples along the top of the creek slope and within the creek for analysis in our testing laboratory.

5. Visually examining recovered soil samples in the laboratory and performing laboratory tests on selected representative samples to develop the soil legend for the project using the Unified Soil Classification System (USCS).

6. Evaluating soil information collected and providing a summary of results along with recommendations for stabilization of the areas of concern.

The scope of our services did not include an environmental assessment for determining the presence or absence of wetlands or hazardous or toxic materials in the soil, bedrock, groundwater, or air, on or below or around this site. Any statements in this report or on the boring logs regarding odors, colors, unusual or suspicious items or conditions are strictly for the information of our Client.

2 SITE CONDITIONS

2.1 Site Features

The project site is along the creek running east-west, starting at McMullen Booth Road, north of Cedar Street, and following eastward past the condominiums along the north side and ending where the creek bends northeastward. The site is generally clear on the northern side of the creek with condominiums approximately 30 feet from the top edge of the creek slope. Along the southern side of the creek is heavily overgrown flora, making access difficult for large equipment. Stabilizing rock is placed along the creek for approximately 260-ft.

starting at McMullen Booth Road.

Slope failure is visible at multiple locations along the creek banks as shown in the following photographs taken on June 23, 2017. According to information provided by Pinellas County, the County hired a contractor in 2015 to remove the accumulated sediment that had sloughed off the banks, repair washouts and other erosion, and restore the historical cross section of the creek.

We have performed Geotechnical explorations in the past at the eastern side of this current project alignment for a future utility that was proposed to cross underneath the creek and travel along the easement between condominium buildings. Here, a 15-ft. Standard Penetration Test (SPT) boring was performed north of the creek and a 5-ft. hand auger was performed close to the water’s edge. In these boreholes, loose to medium dense SP-SM material was encountered to 10-ft. in the SPT boring and to 3-ft. in the hand auger. Medium dense SC material followed this layer in both to the depth the boreholes were completed at.

Figure 1: North bank approximately 10 feet west of boring location SPT-02.

Figure 2: South bank at boring location SPT-02.

Figure 3: South bank between boring locations SPT-02 and SPT-03

2.2 Pinellas County Soil Survey

We reviewed the USDA Soil Conservation Service Soil Survey of Pinellas County, Florida for general information on the shallow soils in the vicinity of the site. The survey area data is Version 13, dated September 16, 2016 with aerial images photographed between December 17, 2013 thru February 28, 2014. The USDA Soil Conservation Service Soil Survey outlines approximate areas dominated by a particular shallow soil type. Small areas of other soils may occur within the mapping unit.

The project area is within one mapping unit: Placid fine sand, frequently ponded, 0 to 1 percent slopes (25).

This mapping unit has a parent material of sandy marine deposits with a typical profile of fine sand from zero to 80 inches. The material is very poorly drained and has a high to very high capacity to transmit water.

The USDA Soil Conservation Service lists the depth to water table at 0 inches.

The USDA Soil Survey is not necessarily an exact representation of the soils on the site. The mapping is based on interpretation of aerial maps with scattered shallow borings for confirmation. Accordingly, borders between mapping units are approximate and the change may be transitional. Differences may also occur from the typical stratigraphy, and small areas of other similar and dissimilar soils may occur within the soil mapping unit. Additionally, urban development and drainage features may also affect soil types encountered and water table depths. As such, there may be differences in the mapped description and the boring descriptions obtained for this report. The survey is, however, a good basis for evaluating the shallow soil conditions of the area. The NRCS-USDA Soil Survey Map (Sheet 3) can be found in the Appendix.

2.3 Topographic Survey

Based on our review of the USGS Topographic Maps, 7.5 Minute Series “Safety Harbor Quadrangle NGVD 1929” dated 1998 and 1943, the approximate ground surface elevation in the vicinity of the borings is about 20 to 30 feet (NGVD 1929). The elevation has not appeared to have changed drastically between these two dates. The referenced USGS Topographic Map, (Sheet 4) can be found in the Appendix.

A Topographic Survey of Basin 13 Channel B McMullen Booth Road to Elm Street was performed in 2017 and provided to MC2 by CH2M. Elevations are based on North American Vertical Datum 1988 (NAV88).

NA88 has a parent benchmark as a part of a national geodetic survey monument stamped “Safety 0” having an elevation of 18.28-feet. According to this survey, the approximate elevations for SPT-01 thru SPT-04 are 23, 20, 21 and 18-ft., respectively.

3 FIELD EXPLORATION PROGRAM

The field exploration program consisted of performing SPT borings along the top of the creek’s banks, along with collected soil samples from the top of the bank and the bottom of the creek for gradation analyses and proctor testing. The SPT borings were performed by our subcontractor, Suncoast Drilling, on July 10, 2017. The field exploration services were performed under the direct supervision of one of our qualified staff geologists and overseen by one of our senior geotechnical engineers. Mr. David Paiko of CH2M was also present during the drilling of the borings.

3.1 Standard Penetration Test (SPT) Borings

A total of four (4) SPT borings were completed at the site in general accordance with ASTM D1586 (Standard Test Method for Penetration Test and Split Barrel Sampling of Soils) by a track-mounted BR-2500 drill rig using a safety hammer and wet-rotary procedure. Representative soil samples were obtained using the split-barrel sampling procedure. In this procedure, a 2-in. outer-diameter, split-barrel sampler is driven into the soil by a 140-lb hammer with a free-fall of 30-in. The number of blows required to drive the sampler through a 12-in. interval, after its initial penetration of 6-in., is termed the Standard Penetration Resistance, or "N" value, and is indicated for each sample on the boring log. The "N" value may be taken as an empirical indication of the relative density and/or consistency of soils in-situ. Hand auger borings were performed in the top 4 feet of the borings along the northern bank to avoid potential conflict with underground utilities.

Soil samples, recovered during the field exploration program, were placed into air-tight glass containers and labeled with the project number, boring number, sample number and date drilled, and returned to our office to confirm field classification and perform laboratory testing, as required. All soil samples collected will be retained in house for 60-days from the date of release of this report and will be subsequently discarded without further notice unless requested otherwise in writing.

Groundwater, if encountered, is measured during the advancement of our borings and prior to the introduction of bentonite to the drilling fluid. Once bentonite is added, an accurate groundwater level is difficult to measure at the time of drilling. Upon completion of our drilling, all test borings were backfilled from the bottom up using bentonite pellets in general accordance with applicable procedures.

3.2 Proctor and Full Gradation Sampling

In addition to the SPT test borings, bulk soil samples were taken from a depth of 1 to 2 feet at SPT-04 for proctor testing and, at a depth of 0.5 to 1.5 feet from the bottom of the creek near SPT-01 for full gradation analyses. This sampling was performed using a manually-operated shovel and collecting the soil in sample bags that were transported back to our Tampa office.

4 LABORATORY TESTING

Representative soil samples collected from the SPT borings were visually reviewed in the laboratory by a geotechnical engineer to confirm the field classifications. The samples were classified and stratified in general accordance with the USCS. Soil classification was based on visual observations with the results of the laboratory testing used to confirm the visual classification. Laboratory tests completed on selected soil samples retrieved for this project include:

four (4) percent passing U.S. standard sieve no. 200 in accordance with ASTM D-1140, two (2) full gradation using sieve analysis in accordance with ASTM D-6913, six (6) moisture content determinations in accordance with ASTM D-2216, two (2) organic content determinations in accordance with ASTM D-2974, and one (1) proctor determination in accordance with ASTM D-1557.

Results for each of these laboratory tests are summarized below and are also presented at the respective sample depths on the individual gINT boring logs provided in the Appendix. The modified Proctor result and grain size distribution curves are also in the Appendix.

Table 1 – Laboratory Test Results

Boring No. (Depth) Moisture Content

Percent Passing -200 Sieve

Organic Content

Maximum Dry

Density (pcf)

Optimum Moisture Content

USCS

Class.

SPT-01 (13.5’-14’) 18.1 18.5 - - - SC

SPT-02 (4’-6’) 20.4 8.5 1.6 - - SP-SC

SPT-03 (13.5’-15’) 20.0 14.3 - - - SC

SPT-04 (3.5’-4’) 122.2 58.9 20.9 - - ML

Near SPT-01 adjacent to creek bottom (.5’)

7.2 3.0 - - - SP

SPT-01 adjacent to creek bottom (1.5’)

25.7 17.9 - - - SC

SPT-04 (1’-2’) - - - 111.5 12.8 SM

5 SUBSURFACE CONDITIONS

5.1 Subsurface Soil and Groundwater Conditions

The subsurface conditions were explored using four (4) SPT borings drilled to a depth of fifteen feet. The borings were located in the field by MC2 personnel measuring distances from existing site features. Mr. David Paiko of CH2M was also on site to observe and approve locations. The approximate boring locations are presented on the Boring Location Map, Sheet 2 in the Appendix. The utilization of a FL state licensed surveyor to provide accurate locations of the SPT borings was not part of our scope of services. However, we can provide this service, if necessary.

The soil descriptions presented herein are of a generalized nature to highlight the major subsurface stratification features and material characteristics. The Subsurface Boring Profiles, Sheet 5 and the individual Soil Profiles logs, included in the Appendix, should be reviewed for specific information at individual boring locations. These profiles include soil description, stratification, penetration resistances, and laboratory test results. The stratification shown on the boring profiles represents the conditions only at the actual boring location. Variations may occur and should be expected between boring locations.

In general, the subsurface conditions consisted of mostly very loose to loose and medium dense, poorly-graded fine SAND (SP) to SAND with silt (SP-SM) or SAND with clay (SP-SC), from the ground surface to approximately 9 to 10 ft. below ground surface (bgs). One exception is at boring location SPT-04 where grayish brown, sandy SILT (ML) with an organic content of 20.9% was encountered from approximately 3.5 to 4 ft. bgs. Beneath this layer is loose to medium dense clayey SAND (SC) to 13.5 to 15 ft. bgs. Underlying the clayey SAND is loose to medium dense SAND (SP-SM) with silt to the boring termination depth of 15 ft. bgs.

The groundwater depth was measured from 7 to 8 ft. bgs in the boreholes at the time of drilling.

In general, groundwater levels tend to fluctuate during periods of prolonged drought and extended rainfall and are affected by man-made influences such as drainage conveyance systems. In addition, a seasonal effect will also occur in which higher groundwater levels are normally recorded in rainy seasons. If the groundwater level is critical to design or construction, temporary observation wells should be installed along the alignment to monitor groundwater fluctuations over a period of time and permit more accurate determinations of wet and dry seasonal levels. We recommend that the Contractor determine the actual groundwater levels at the time of the construction to determine groundwater impact on the construction procedure.

6 OBSERVATIONS AND RECOMMENDATIONS

6.1 General

The following evaluations and conclusions have been developed on the basis of the previously described project characteristics, our review of published data, information provided by others, our site investigation and subsurface conditions encountered during our exploration.

Once final design plans and specifications are available, a general review by MC2 is strongly recommended as a means to check that the evaluations made in preparation of this report are correct and that recommendations are properly interpreted and implemented.

6.2 Site Evaluation

In general, the subsurface conditions indicate very loose to loose sands to 8 to 10 feet followed by medium dense sands with exception to boring SPT-01, which remained loose throughout the boring depth.

Groundwater was found to be at approximately 7 to 8 feet below ground surface.

The configuration of the slope of the drainage channel was measured at three locations. The slopes vary from less than 1:1 to approximately 1:1.3. Geotextile is visible on the slope in several of the failed areas as shown in Figure 4 below. Several types of failure were observed along the channel. Sliding and flowing are modes of failure observed on site. Sliding is the downward movement of a soil mass occurring on a surface of rupture and is the most common mode of failure observed. Flowing is a downward movement of soil mass similar to a viscous fluid which appears to be caused in locations where storm water is flowing over the peak of the canal. It is our understanding that the canal has flooded into the surrounding properties in some locations. Based on our boring information, it appears compaction had not properly been performed during placement of the soils.

Figure 4: Slope failure with view of geotextile

Figure 5: Sand bag retaining wall and rip rap

There are several locations where erosion has taken place from surface water from the surrounding areas flowing over into the creek. Several of the areas have rip rap placed where the failure occurred, as shown in Figure 5.

At the areas where we measured the slopes, the incline ranged from 38 to 57 degrees and the vertical height of the slopes varied from 6 to 11 feet. Slope stability was performed using GeoStudio 2012. Our analysis indicates that a factor of safety of less than 1.0 exists under the current conditions. Slopes of 3:1 are required under the existing soil conditions for a safe slope with a factor of safety of 1.5.

7 REHABILITATION

Rehabilitation of the failed slope should address both surface water runoff at the top of the slope and rehabilitation/stabilization of the already failed slope.

Water Runoff Ground water runoff is known to be a significant contributor to initiation of slope failure, therefore, adequate drainage, either surficial and/or subsurface is important. Surface drainage at the top of the slope should be intercepted and diverted to specific locations where water can flow into the canal.

Slope Rehabilitation Due to site specific constraints such as property limits, flattening the slopes does not appear to be a feasible option, therefore, other options for slope rehabilitation and/or stabilization would need to be considered.

Included below are some options that we consider appropriate for addressing the slope failure issues:

GeoGrid – To prevent erosion of the slope and provide stability, a geogrid system can be used such as Stratagrids. The Stratagrids can be combined with traditional erosion protection products or vegetation. For slopes 1H:1V or flatter, primary and secondary geogrids with erosion protection products and vegetation will create a reinforced slope. For slopes steeper than 1H:1V welded wire forms can be used with microgrid face wrap and primary geogrid with location, type and length as required by design. Permanent vegetation will be planted on the face of the slopes and top of bank.

Gabion Walls – A gabion wall could be used to provide stabilization of the toe of the slope over the long-term. Gabion walls are a proprietary gravity retaining wall system that should be designed by the specialty contractor. The wall slope combination should be designed so that it is stable with regards to overall internal and external stability.

These walls use stacked or interconnected structural elements, which utilize rock fill, to resist earth pressures by acting as gravity retaining walls. Rock filled wire gabion baskets are used to construct a gabion wall.

A gabion is a heavy-duty, galvanized steel wire mesh basket, in the shape of a box that is divided by diaphragms into cells. Filled with heavy materials (typically rocks or broken concrete) that cannot escape through the mesh openings, it generally is used as a construction block, becoming part of a larger unit of several gabions tied together to form a structure.

The advantages of gabion walls are that they blend very well with natural surroundings and the preformed baskets are light and easy to work with during construction. Gabion wall design should be performed by an experienced professional engineer licensed in the state of Florida.

Given the steepness of the slope and the constraint of space, we believe that a combination of the geogrid and gabion wall would be the more practicable approach to the rehabilitation and stabilization of the failed areas of the slope. Further, it would be prudent to implement this approach to other areas of the slope that have not failed, as a preventative measure.

We did not do any borings in the areas where the gabion wall would be built, if indeed this would be the selected alternative to stabilize the toe of the slope. Consequently, we are unable at this time to characterize the bearing capacities of the soils that would support the gabion wall. We recommend that after our report is reviewed that we meet with you to discuss the next steps, including selecting the most practicable alternative to address the slope instability issues. We will make ourselves readily available for such a meeting.

8 REPORT LIMITATIONS

The recommendations detailed herein are based on the available limited soil information obtained by MC2 and information provided by CH2M Hill Engineers, Inc. for the proposed project. If there are any revisions to the plans for this project or if deviations from the subsurface conditions noted in this report are encountered during construction, MC2 should be notified immediately to determine if changes of recommendations are required. In the event that MC2 is not retained to perform these functions, MC2 cannot be held responsible for the impact of those conditions on the performance of the project.

The geotechnical engineer warrants that the findings, recommendations, specifications, or professional advice contained herein have been made in accordance with generally accepted professional geotechnical engineering practices in the local area. No other warranties are implied or expressed.

After the plans and specifications are more complete, the geotechnical engineer should be provided the opportunity to review the final design plans and specifications to assess that our engineering recommendations have been properly incorporated into the design documents. At that time, it may be necessary to submit supplementary recommendations. This report has been prepared for the exclusive use of CH2M Hill Engineers, Inc.

APPENDIX

Soil Parameters – Table No. 2

Project Location Map - Sheet 1 Boring Location Map - Sheet 2

NRCS – USDA Soil Survey Map - Sheet 3 USGS Topographic Map - Sheet 4

Subsurface Boring Profiles - Sheet 5 Subsurface Boring Profile Legend - Sheet 6

Individual Soil Profiles – 4 Pages Modified Proctor Test – 1 Page

Grain Size Distribution Test – 2 Pages Test Procedures

Table No. 2

Summary of Soil Parameters Mullet Creek Bank Restoration

Pinellas County, Florida MC2 Project No. T101613.205

Boring

ID

Depth (ft)

N Value

Range Soil Classification

Average Unit Weight (γ)** Angle of

Internal

Friction

Ø **

(degrees)

Earth Pressure Coefficients* Average

Undrained

Cohesion

Cu **

(psf)

Saturated

(pcf)

Submerged

(pcf)

At Rest

(Ko)

Active

(Ka)

Passive

(Kp)

SPT-01

0-10 5-8 SP-SM 105.0 42.6 29 0.5152 0.347 2.88 0

10-14 5 SC 105.0 42.6 29 0.6254 0.347 2.88 0

14-15 6 SP-SM 105.0 42.6 29 0.5152 0.347 2.88 0

SPT-02

0-6.5 2 SP-SM, SP-SC 100.0 37.6 26 0.5616 0.391 2.56 0

6.5-9.5 6 SP-SM 105.0 42.6 29 0.5152 0.347 2.88 0

9.5-13.5 10 SC 110.0 42.6 30 0.6254 0.347 2.88 0

13.5-15 14 SP-SM 110.0 47.6 30 0.5000 0.333 3.00 0

SPT-03

0-4 2-4 SP-SM 100.0 37.6 26 0.5616 0.391 2.56 0

4-9 10-16 SP-SM 110.0 47.6 30 0.5000 0.333 3.00 0

9-15 9-25 SC 110.0 47.6 30 0.5774 0.333 3.00 0

SPT-04

0-9.5 5-16 SP-SM, ML 105.0 42.6 29 0.5152 0.347 2.88 0

9.5-13.5 16 SC 110.0 47.6 30 0.5774 0.333 3.00 0

13.5-15 19 SP-SM 110.0 47.6 30 0.5000 0.333 3.00 0

*Values are for level (non-sloping) backfill; no surcharge loads on backfill

**Based on empirical correlations

NOTE: Hand augers were performed in the top 4 feet at most test boring locations to avoid utilities

The data presented in the Table above was derived empirically by MC2 professional engineers.

NAMEDATE APPROVED BY:REVISION

SUPERVISED BY:

CHECKED BY:

DRAWN BY:

DESIGNED BY:

SHEET NO.MC PROJ. NO.

T101613.205

Mullet Creek Bank Restoration

Clearwater, Pinellas County, Florida

JJ

5808-A Breckenridge Parkway

Tampa, FL 33610

Ph:813-623-3399 Fax:813-623-6636

Geotechnical Consultants

MC SQUARED, INC.

Project Location Map

07/26/2017

07/26/2017

07/27/2017

TC

TC

JH

DATE

NAME

Project Location

Source: Google Earth

Image Date: 1/11/17

AutoCAD SHX Text Jodonna J. Jimenez, P.E.

AutoCAD SHX Text FLORIDA LICENSE No. 47701

AutoCAD SHX Text

FLORIDA ENGINEERING CERTIFICATE OF

AutoCAD SHX Text AUTHORIZATION No. 9191

SUPERVISED BY:

CHECKED BY:

DRAWN BY:

DESIGNED BY:

SHEET NO.MC PROJ. NO.

T101613.205

Mullet Creek Bank Restoration

Clearwater, Pinellas County, Florida

JJ

5808-A Breckenridge Parkway

Tampa, FL 33610

Ph:813-623-3399 Fax:813-623-6636

Geotechnical Consultants

MC SQUARED, INC.

Boring Location Map

07/26/2017

07/26/2017

07/27/2017

TC

TC

JH

DATE

NAME

Source: Google Earth

Image Date: 1/11/17

SPT-01

LEGEND:

Approximate SPT Boring Location

SPT-02

SPT-03

SPT-04

AutoCAD SHX Text Jodonna J. Jimenez, P.E.

AutoCAD SHX Text FLORIDA LICENSE No. 47701

AutoCAD SHX Text

FLORIDA ENGINEERING CERTIFICATE OF

SUPERVISED BY:

CHECKED BY:

DRAWN BY:

DESIGNED BY:

SHEET NO.MC PROJ. NO.

T101613.205

Mullet Creek Bank Restoration

Clearwater, Pinellas County, Florida

JJ

5808-A Breckenridge Parkway

Tampa, FL 33610

Ph:813-623-3399 Fax:813-623-6636

Geotechnical Consultants

MC SQUARED, INC.

NRCS - USDA Soil Survey Map

07/26/2017

07/26/2017

07/27/2017

TC

TC

JH

DATE

NAME

SOURCE: United States Department of Agriculture

AutoCAD SHX Text Jodonna J. Jimenez, P.E.

AutoCAD SHX Text FLORIDA LICENSE No. 47701

AutoCAD SHX Text

FLORIDA ENGINEERING CERTIFICATE OF

SUPERVISED BY:

CHECKED BY:

DRAWN BY:

DESIGNED BY:

SHEET NO.MC PROJ. NO.

T101613.205

Mullet Creek Bank Restoration

Clearwater, Pinellas County, Florida

JJ

5808-A Breckenridge Parkway

Tampa, FL 33610

Ph:813-623-3399 Fax:813-623-6636

Geotechnical Consultants

MC SQUARED, INC.

USGS Topographic Map

07/26/2017

07/26/2017

07/27/2017

TC

TC

JH

DATE

NAME

Project Location

SAFETY HARBOR QUADRANGLE, 2015

CLEARWATER, FLORIDA - POLK COUNTY

7.5 - MINUTE SERIES, NAVD 1988

AutoCAD SHX Text Jodonna J. Jimenez, P.E.

AutoCAD SHX Text FLORIDA LICENSE No. 47701

AutoCAD SHX Text

FLORIDA ENGINEERING CERTIFICATE OF

Date : 7/10/2017

Boring No. : SPT-01

N

Date : 7/10/2017

Boring No. : SPT-03

Date : 7/10/2017

Boring No. : SPT-02

N

10 9

N

Date : 7/10/2017

Boring No. : SPT-04

N

Boring Terminated at 15 ft.

Boring Terminated at 15 ft.

Boring Terminated at 15 ft.

Boring Terminated at 15 ft.

2 2

0 0

*N Values Drawn At Top Of Interval

DATE NAME REVISION APPROVED BY

MC SQUARED INC.

Geotechnical Consultants

5808-A Breckenridge Parkway

Tampa, FL 33610

Ph : 813-623-3399 Fax : 813-623-6636

NAME

FLORIDA ENGINEERING CERTIFICATE OF

AUTHORIZATION No. 9191

Jodonna J. Jimenez, P.E.

FLORIDA LICENSE No. 67882

DESIGNED BY:

DRAWN BY:

CHECKED BY:

SUPERVISED BY:

TC

TC

JJ

JJ

DATE

7/24/17

7/24/17

7/25/17

SUBSURFACE BORING PROFILES

Hermine Damage at Mullet Creek

Clearwater, FL Pinellas County

MC² PROJ. NO. SHEET NO.

T101613.205

E L E

V A

T I O

N

F

E E

T

E L E

V A

T I O

N

F

E E

T

HA

HA

HA

HA

HA

HA

LEGEND

(SP) Poorly Graded Sand

NOTES:

Water Table After 24 Hours

Water Table At Time Of Drilling

(SM) Silty Sand

(SP-SM) Poorly Graded Sand With Silt

(SC) Clayey Sand

(SP-SC) Poorly Graded Sand With Clay

(CL) Lean Clay

(CH) Fat Clay

(MH) Elastic Silt

(ML) Silt

Limestone

Asphalt

Bedrock

Concrete

Fill

Peat

Top Soil (CL-ML) Silty Clay

Groundwater Not Encountered

GNA Groundwater Not Apparent

CL Center Line

RT Right Of Center Line

LT Left of Center Line

HA Hand Auger

PA Power Auger

NMC Natural Moisture Content (%)

-200 Fines Passing A No. 200 Sieve (%)

PI Plasticity Index

NP Non Plastic

LL Liquid Limit

OC Organic Content (%)

N SPT N-Value

WOH Weight-Of-Hammer

WOR Weight-Of-Rod

CPT Cone Penetrometer Test

SPT Standard Penetration Test

DT Dilatometer Test

LOC Loss Of Circulation

ROC Regain Of Circulation

REC Rock Core Recovery(%)

RQD Rock Quality Designation

ST Shelby Tube Sample

Granite

Schist

Gneiss

GRANULAR MATERIALS- RELATIVE DENSITY

VERY LOOSE

LOOSE

MEDIUM

DENSE

VERY DENSE

£ 4

5-10

11-30

31-50

GREATER THAN 50

SILTS AND CLAYS CONSISTENCY

VERY SOFT

SOFT

FIRM

STIFF

VERY STIFF

HARD

VERY HARD

£ 2

3-4

5-8

9-15

16-30

30-50

GREATER THAN 50

Bedrock

(GAB) Graded Aggregate Base

Limerock Base

(OH) Organic Clay

(OL) Organic Silt

(WLS) Weathered Limestone

(PWR) Partially Weathered Rock

GNE

qᵤ Unconfined Compressive Strength From Pocket

Penetrometer In tsf

SPT Spoon Inside Diameter 1 3/8"

SPT Spoon Outside Diameter 2"

ASTM Standard Drop Safety Hammer

Average Hammer Drop Height 30"

Hammer Weight 140 lbs

SPT (BLOWS/FT)

SPT (BLOWS/FT)

BGS Below Ground Surface

No. 57 Stone

GNM Groundwater Not Measured

NAMEDATE APPROVED BY:REVISION

SUPERVISED BY:

CHECKED BY:

DRAWN BY:

DESIGNED BY:

SHEET NO.MC PROJ. NO.

T101613.205

Mullet Creek Bank Restoration

Clearwater, Pinellas County, Florida

JJ

5808-A Breckenridge Parkway

Tampa, FL 33610

Ph:813-623-3399 Fax:813-623-6636

Geotechnical Consultants

MC SQUARED, INC.

Legend

07/26/2017

07/26/2017

07/27/2017

TC

TC

JH

DATE

NAME

AutoCAD SHX Text Jodonna J. Jimenez, P.E.

AutoCAD SHX Text FLORIDA LICENSE No. 47701

AutoCAD SHX Text

FLORIDA ENGINEERING CERTIFICATE OF

3-3-4-5 (7)

5-4-4-2 (8)

1-2-3-4 (5)

4-2-4 (6)

HA

HA

SS

SS

SS

SS

Loose light gray to brown, poorly graded fine SAND with silt

Loose, gray, clayey fine SAND

Loose, grayish brown, poorly graded fine SAND with silt

Bottom of hole at 15.0 feet.

SP-SM

SC

SP-SM

GROUND ELEVATION 23 ft

LOGGED BY B. Crowson

DRILLING METHOD Split Spoon AT TIME OF DRILLING 8.0 ft / Elev 15.0 ft

AT END OF DRILLING ---

AFTER DRILLING ---

HOLE SIZE 4 inches

DRILLING CONTRACTOR Suncoast Drilling, LLC GROUND WATER LEVELS:

CHECKED BY J. Jimenez

DATE STARTED 7/10/17 COMPLETED 7/10/17

NOTES BR-2500, Safety Hammer

ORGANIC CONTENT %

2 5 5 0 7 5

R E

C O

V E

R Y

(R

Q D

B

LO

W C

O U

N T

S (N

V A

LU

E

S A

M P

LE

T

Y P

E N

U M

B E

R

SPT N VALUE

20.8 40.6 60.4 80.2

MATERIAL DESCRIPTION

U S

C S

G ro up S ym bo l

G R

A P

H

IC

L O

G

D E

P T

H ft

0.0

2.5

5.0

7.5

10.0

12.5

15.0

E

LE

V

(f t)

FINES CONTENT (%)

20 40 60 80

2 5 5 0 7 5

PL LLMC

CLIENT CH2M Hill

PROJECT NUMBER T101613.205

PROJECT NAME Hermine Damage at Mullet Creek

PROJECT LOCATION Clearwater, FL Pinellas County

BORING ID: SPT-01BORING ID: SPT-01Soil Profile

1-1-1-0 (2)

1-3-3-4 (6)

4-4-6-8 (10)

4-7-7 (14)

HA

HA

SS

SS

SS

SS

Very pale brown. grayish brown, poorly graded fine SAND with silt

Very loose, grayish brown, poorly graded fine SAND with clay

Loose, very pale brown, poorly graded fine SAND with silt

Loose to medium dense, gray, clayey fine SAND

Medium dense, very light gray, poorly graded fine SAND with silt

Bottom of hole at 15.0 feet.

SP-SM

SP-SC

SP-SM

SC

SP-SM

GROUND ELEVATION 20 ft

LOGGED BY B. Crowson

DRILLING METHOD Split Spoon AT TIME OF DRILLING 7.0 ft / Elev 13.0 ft

AT END OF DRILLING ---

AFTER DRILLING ---

HOLE SIZE 4 inches

DRILLING CONTRACTOR Suncoast Drilling, LLC GROUND WATER LEVELS:

CHECKED BY J. Jimenez

DATE STARTED 7/10/17 COMPLETED 7/10/17

NOTES BR-2500, Safety Hammer

ORGANIC CONTENT %

2 5 5 0 7 5

R E

C O

V E

R Y

(R

Q D

B

LO

W C

O U

N T

S (N

V A

LU

E

S A

M P

LE

T

Y P

E N

U M

B E

R

SPT N VALUE

20.8 40.6 60.4 80.2

MATERIAL DESCRIPTION

U S

C S

G ro up S ym bo l

G R

A P

H

IC

L O

G

D E

P T

H ft

0.0

2.5

5.0

7.5

10.0

12.5

15.0

E

LE

V

(f t)

FINES CONTENT (%)

20 40 60 80

2 5 5 0 7 5

PL LLMC

CLIENT CH2M Hill

PROJECT NUMBER T101613.205

PROJECT NAME Hermine Damage at Mullet Creek

BORING ID: SPT-02BORING ID: SPT-02Soil Profile

2-1-1-2 (2)

2-2-2-4 (4)

5-6-10-8 (16)

5-5-5-3 (10)

3-4-5-6 (9)

8-11-14 (25)

SS

SS

SS

SS

SS

SS

Very loose to medium dense, light gray to dark grayish brown, poorly graded fine SAND with silt

Loose to medium dense, gray, clayey fine SAND

Bottom of hole at 15.0 feet.

SP-SM

SC

GROUND ELEVATION 21 ft

LOGGED BY B. Crowson

DRILLING METHOD Split Spoon AT TIME OF DRILLING 8.0 ft / Elev 13.0 ft

AT END OF DRILLING ---

AFTER DRILLING ---

HOLE SIZE 4 inches

DRILLING CONTRACTOR Suncoast Drilling, LLC GROUND WATER LEVELS:

CHECKED BY J. Jimenez

DATE STARTED 7/10/17 COMPLETED 7/10/17

NOTES BR-2500, Safety Hammer

ORGANIC CONTENT %

2 5 5 0 7 5

R E

C O

V E

R Y

(R

Q D

B

LO

W C

O U

N T

S (N

V A

LU

E

S A

M P

LE

T

Y P

E N

U M

B E

R

SPT N VALUE

20.8 40.6 60.4 80.2

MATERIAL DESCRIPTION

U S

C S

G ro up S ym bo l

G R

A P

H

IC

L O

G

D E

P T

H ft

0.0

2.5

5.0

7.5

10.0

12.5

15.0

E

LE

V

(f t)

FINES CONTENT (%)

20 40 60 80

2 5 5 0 7 5

PL LLMC

CLIENT CH2M Hill

PROJECT NUMBER T101613.205

PROJECT NAME Hermine Damage at Mullet Creek

BORING ID: SPT-03BORING ID: SPT-03Soil Profile

1-2-3-5 (5)

5-5-4-5 (9)

5-6-10-9 (16)

7-9-10 (19)

HA

HA

SS

SS

SS

SS

Grayish brown to light brown, poorly graded fine SAND with silt

Grayish brown, sandy SILT

Loose to medium dense, very light gray, white, poorly graded fine SAND with silt

Medium dense, gray, clayey fine SAND

Medium dense, gray, poorly graded fine SAND with silt

Bottom of hole at 15.0 feet.

SP-SM

ML

SP-SM

SC

SP-SM

GROUND ELEVATION 18 ft

LOGGED BY B. Crowson

DRILLING METHOD Split Spoon AT TIME OF DRILLING 7.0 ft / Elev 11.0 ft

AT END OF DRILLING ---

AFTER DRILLING ---

HOLE SIZE 4 inches

DRILLING CONTRACTOR Suncoast Drilling, LLC GROUND WATER LEVELS:

CHECKED BY J. Jimenez

DATE STARTED 7/10/17 COMPLETED 7/10/17

NOTES BR-2500, Safety Hammer

ORGANIC CONTENT %

2 5 5 0 7 5

R E

C O

V E

R Y

(R

Q D

B

LO

W C

O U

N T

S (N

V A

LU

E

S A

M P

LE

T

Y P

E N

U M

B E

R

SPT N VALUE

20.8 40.6 60.4 80.2

MATERIAL DESCRIPTION

U S

C S

G ro up S ym bo l

G R

A P

H

IC

L O

G

D E

P T

H ft

0.0

2.5

5.0

7.5

10.0

12.5

15.0

E

LE

V

(f t)

FINES CONTENT (%)

20 40 60 80

2 5 5 0 7 5

PL LLMC

CLIENT CH2M Hill

PROJECT NUMBER T101613.205

PROJECT NAME Hermine Damage at Mullet Creek

PROJECT LOCATION Clearwater, FL Pinellas County

BORING ID: SPT-04BORING ID: SPT-04Soil Profile

122.2

AASHTO T-180

Project: Mullet Creek Bank Restoration Project No.: T101613.205

Sample Location:SPT-04, 1'-2' bgs Date: 7/18/2017

Client: CH2M Hill Lab Technician: SG

Sample Description: Grayish brown silty sand (SM)

Sample No. 2067

Maximum Dry Density, (pcf) 111.5

Optimum Moisture Content, (%) 12.8

Respectfully Submitted, These test results apply only to the specific locations noted and may not represent any other location. MC Squared, Inc.

Reports may not be reproduced, except in full, without permission by Mc Squared, Inc.

(Fla. Engineering Business No. 9191)

Winstson L. Stewart

FL License No. 81643

Modified Proctor Test

107.5

108.0

108.5

109.0

109.5

110.0

110.5

111.0

111.5

112.0

9 11 13 15

D e n s it y

(p c f)

Moisture, (%)

True Data

GRAIN SIZE DISTRIBUTION TEST REPORT

Project No.: T101613.205 Date: 6/29/2017

Project: Mullet Creek Bank Restoration

Sample Location: SPT-01 near creek bottom 0.5' bgs

Soil Description: light brown poorly graded fine sand

Soil Classification: SP LL PI

NMC % 7.2

% Gravel % Sand %-200

0.0 97.0 3.0

D60 D30 D10 CC CU

MC SQUARED, INC.

0.0

20.0

40.0

60.0

80.0

100.0

0.010.1110

P E

R C

E N

T F

IN

E

R

GRAIN SIZE, mm

GRAIN SIZE DISTRIBUTION

Sieve 3/8 4 10 20 40 60 100 140 200

GRAIN SIZE DISTRIBUTION TEST REPORT

Project No.: T101613.205 Date: 6/29/2017

Project: Mullet Creek Bank Restoration

Sample Location: SPT-01 near creek bottom 1.5' bgs

Soil Description: grayish brown clayey sand

Soil Classification: SC LL PI

NMC % 25.7

% Gravel % Sand %-200

0.0 81.8 18.2

D60 D30 D10 CC CU

0.17 0.13 - - -

MC SQUARED, INC.

0.0

20.0

40.0

60.0

80.0

100.0

0.010.1110

P E

R C

E N

T F

IN

E

R

GRAIN SIZE, mm

GRAIN SIZE DISTRIBUTION

Sieve 3/8 4 10 20 40 60 100 140 200

TEST PROCEDURES

The general field procedures employed by MC Squared, Inc. (MC2) are summarized in the American Society for Testing and Materials (ASTM) Standard D420, which is entitled "Investigating and Sampling Soil and Rock". This recommended practice list recognized methods for determining soil and rock distribution and groundwater conditions. These methods include geophysical and in-situ methods as well as borings.

Standard Drilling Techniques

To obtain subsurface samples, borings are drilled using one of several alternate techniques depending upon the subsurface conditions. Some of these techniques are:

In Soils:

a) Continuous hollow stem augers.

b) Rotary borings using roller cone bits or drag bits, and water or drilling mud to flush the hole.

c) "Hand" augers.

In Rock:

a) Core drilling with diamond-faced, double or triple tube core barrels.

b) Core boring with roller cone bits.

Hollow Stem Augering: A hollow stem auger consists of a hollow steel tube with a continuous exterior spiral flange termed a flight. The auger is turned into the ground, returning the cuttings along the flights.

The hollow center permits a variety of sampling and testing tools to be used without removing the auger.

Mud Rotary: In situations where unconsolidated materials are anticipated, the direct-rotary or “mud” rotary method may be used as a more effective method for obtaining soil samples. The fluid used, which is typically stored in an aluminum tub (also known as a “mudtub”), is a mix of water and bentonite, also known as a bentonite slurry or “mud”. This fluid circulates into the borehole and then returns to the mudtub using a pump system. A loss of circulation, partially or otherwise, may signify a void at that sample depth. The key advantage of using this drilling method is that it stabilizes the borehole wall while drilling in unconsolidated formations, due to the buildup of a filter cake on the wall.

Core Drilling: Soil drilling methods are not normally capable of penetrating through hard cemented soil, weathered rock, coarse gravel or boulders, thin rock seams, or the upper surface of sound, continuous rock. Material which cannot be penetrated by auger or rotary soil-drilling methods at a reasonable rate is designated as “refusal material”. Core drilling procedures are required to penetrate and sample refusal materials.

Prior to coring, casing may be set in the drilled hole through the overburden soils, to keep the hole from caving and to prevent excessive water loss. The refusal materials are then cored according to ASTM D-2113 using a diamond-studded bit fastened to the end of a hollow, double or triple tube core barrel.

This device is rotated at high speeds, and the cuttings are brought to the surface by circulating water.

Core samples of the material penetrated are protected and retained in the swivel-mounted inner tube.

Upon completion of each drill run, the core barrel is brought to the surface, the core recovery is measured, and the core is placed, in sequence, in boxes for storage and transported to our laboratory.

Sampling and Testing in Boreholes

Several techniques are used to obtain samples and data in soils in the field; however, the most common methods in this area are:

a) Standard Penetration Testing

b) Undisturbed Sampling

c) Dynamic Cone Penetrometer Testing

d) Water Level Readings

The procedures utilized for this project are presented below.

Standard Penetration Testing: At regular intervals, the drilling tools are removed and soil samples obtained with a standard 2 inch diameter split tube sampler connected to an A or N-size rod. The sampler is first seated 6 inches to penetrate any loose cuttings, and then driven an additional 12 inches with blows of a 140 pound safety hammer falling 30 inches. Generally, the number of hammer blows required to drive the sampler the final 12 inches is designated the "penetration resistance" or "N" value, in blows per foot (bpf). The split barrel sampler is designed to retain the soil penetrated, so that it may be returned to the surface for observation. Representative portions of the soil samples obtained from each split barrel sample are placed in jars, sealed and transported to our laboratory.

The standard penetration test, when properly evaluated, provides an indication of the soil strength and compressibility. The tests are conducted according to ASTM Standard D1586. The depths and N-values of standard penetration tests are shown on the Boring Logs. Split barrel samples are suitable for visual observation and classification tests but are not sufficiently intact for quantitative laboratory testing.

Water Level Readings: Water level readings are normally taken in the borings and are recorded on the Boring Records. In sandy soils, these readings indicate the approximate location of the hydrostatic water level at the time of our field exploration. In clayey soils, the rate of water seepage into the borings is low and it is generally not possible to establish the location of the hydrostatic water level through short-term water level readings. Also, fluctuation in the water level should be expected with variations in precipitation, surface run-off, evaporation, and other factors. For long-term monitoring of water levels, it is necessary to install piezometers.

The water levels reported on the Boring Logs are determined by field crews immediately after the drilling tools are removed, and several hours after the borings are completed, if possible. The time lag is intended to permit stabilization of the groundwater level that may have been disrupted by the drilling operation.

Occasionally the borings will cave-in, preventing water level readings from being obtained or trapping drilling water above the cave-in zone.

Boring Logs

The subsurface conditions encountered during drilling are reported on a field boring log prepared by the Driller. The log contains information concerning the boring method, samples attempted and recovered, indications of the presence of coarse gravel, cobbles, etc., and observations of groundwater. It also contains the driller's interpretation of the soil conditions between samples. Therefore, these boring records contain both factual and interpretive information. The field boring records are kept on file in our office.

After the drilling is completed a geotechnical professional classifies the soil samples and prepares the final Boring Logs, which are the basis for our evaluations and recommendations.

Soil Classification

Soil classifications provide a general guide to the engineering properties of various soil types and enable the engineer to apply his past experience to current problems. In our investigations, samples obtained during drilling operations are examined in our laboratory and visually classified by an engineer. The soils are classified according to consistency (based on number of blows from standard penetration tests), color and texture. These classification descriptions are included on our Boring Logs.

The classification system discussed above is primarily qualitative and for detailed soil classification two laboratory tests are necessary; grain size tests and plasticity tests. Using these test results the soil can be classified according to the AASHTO or Unified Classification Systems (ASTM D-2487). Each of these classification systems and the in-place physical soil properties provides an index for estimating the soil's behavior. The soil classification and physical properties are presented in this report.

The following table presents criteria that are typically utilized in the classification and description of soil and rock samples for preparation of the Boring Logs.

Relative Density of Cohesionless Soils

From Standard Penetration Test Consistency of Cohesive Soils

Very Loose < 4 bpf

Loose 5 - 10 bpf

Medium Dense 11 - 30 bpf

Dense 31 - 50 bpf

Very Dense > 50 bpf

(bpf = blows per foot, ASTM D 1586)

Very Soft < 2 bpf

Soft 3 - 4 bpf

Firm 5 - 8 bpf

Stiff 9 - 15 bpf

Very Stiff 16 - 30 bpf

Hard 30 – 50 bpf

Very Hard > 50 bpf

Relative Hardness of Rock Particle Size Identification

Very Soft Hard Rock disintegrates or easily compresses to touch; can be hard to very hard soil.

Soft May be broken with fingers.

Moderately Soft May be scratched with a nail, corners and edges may be broken with fingers.

Moderately Hard Light blow of hammer required to break samples.

Hard Hard blow of hammer required to break sample.

Boulders Larger than 12"

Cobbles 3" - 12"

Gravel Coarse 3/4" - 3" Fine 4.76mm - 3/4"

Sand Coarse 2.0 - 4.76 mm Medium 0.42 - 2.00 mm Fine 0.42 - 0.074 mm

Fines (Silt or Clay) Smaller than 0.074 mm

Rock Continuity Relative Quality of Rocks

RECOVERY = Total Length of Core x 100 % Length of Core Run

RQD = Total core, counting only pieces > 4" long x 100 % Length of Core Run

Description Core Recovery %

Incompetent Less than 40

Competent 40 - 70

Fairly Continuous 71 - 90

Continuous 91 - 100

Description RQD %

Very Poor 0 - 25 %

Poor 25 - 50 %

Fair 50 - 75 %

Good 75 - 90 %

Excellent 90 - 100 %