B08_Solicit_Geo_Report-Proposed_Elevator_ATTCH_4.pdf

ECS Florida, LLC Geotechnical Engineering Report Guy Bradley Flamingo Visitor Center - Proposed Elevator

1 Flamingo Lodge Highway Homestead, Miami-Dade County, Florida 33034

ECS Project Number 25:3404

November 20, 2018

Guy Bradley Flamingo Visitor Center – Proposed Elevator November 20, 2018 ECS Project No. 25:3404 Page 1

TABLE OF CONTENTS

EXECUTIVE SUMMARY

1.0 INTRODUCTION

1.1 General

1.2 Scope of Services

1.3 Authorization

2.0 PROJECT INFORMATION

2.1 Project Location

2.2 Past Site History/Uses

2.3 Current Site Conditions

2.4 Proposed Construction

2.4.1 Site Civil Features

2.4.2 Structural Information/Loads

3.1 Field Exploration Program

3.1.1 Test Borings

3.2 Regional/Site Geology

3.3 Fema flood Mapping

3.4 Subsurface Characterization

3.5 Groundwater Observations

4.0 LABORATORY TESTING

5.0 DESIGN RECOMMENDATIONS

5.1 Building Design

5.1.1 Helical Piles

5.1.2 Soil Parameters

6.0 SITE CONSTRUCTION RECOMMENDATIONS

6.1 Subgrade Preparation

6.1.1 Demolition

6.1.2 Stripping and Grubbing

6.1.3 Compaction

6.1.4 Site Temporary Dewatering

6.1.5 Subgrade Stabilization

6.2 Earthwork Operations

6.2.1 Structural Fill Materials

6.2.2 Compaction

6.3 General Construction Considerations

7.0 CLOSING

ECS Project No. 25:3404 Page 2

APPENDICES

Appendix A – Drawings & Reports

• Site Location Diagram

• Boring Location Diagram

• Geologic Map

• FEMA Flood Map

Appendix B – Field Operations

• Reference Notes for Boring Logs

• Boring Logs B-1 and B-2

Appendix C – Laboratory Testing Results

• Laboratory Testing Summary

ECS Project No. 25:3404 Page 3

EXECUTIVE SUMMARY

The following summarizes geotechnical information and recommendations for the design of the proposed elevator foundation for the Guy Bradley Flamingo Visitor Center project located in Homestead, Florida. Further, our principal foundation recommendations are summarized.

Information gleaned from this executive summary should not be utilized in lieu of reading the entire geotechnical report.

• The geotechnical exploration performed for the planned proposed elevator included two Standard Penetration Test (SPT) soil test borings drilled to depths of 30 feet below existing grades.

• Based on our subsurface exploration, our soil test borings encountered asphalt underlain by crushed limestone base material and topsoil as surface covers. The soil profile at the site generally consists of firm to very soft (CL) clay with sand to a depth of approximately ten feet below land surface (bls), underlain by medium dense to very dense weathered limestone to the boring termination depths of 30 feet bls.

• The planned two-story above grade elevator structure, located within a VE (EL 16 Feet) Flood Zone, can be supported by a deep foundation system consisting of helical piles.

Details of pile capacities, the assumed foundation subgrade elevations, and loads, are contained in the body of this report.

ECS Project No. 25:3404 Page 4

1.0 INTRODUCTION

1.1 GENERAL

The purpose of this study was to provide geotechnical design and foundation recommendations for the Guy Bradley Flamingo Visitor Center Proposed Elevator project located in Homestead, Florida.

The recommendations developed for this report are based on project information supplied by Baker Design Build. This report contains the results of our subsurface explorations and laboratory testing programs, site characterization, engineering analyses, and recommendations for the design and construction of planned improvement.

1.2 SCOPE OF SERVICES

To obtain the necessary geotechnical information required for design of the proposed structure, two Standard Penetration Test (SPT) soil test borings were drilled to depths of 30 feet below existing land surface (bls); these borings were located within the vicinity of the proposed elevator shaft. A laboratory-testing program was also implemented to characterize the physical and engineering properties of the subsurface soils.

This report discusses our exploratory and testing procedures, presents our findings and evaluations and includes the following.

• A brief review and description of our field and laboratory test procedures and the results of testing conducted.

• A review of area and site geologic conditions.

• A review of subsurface soil stratigraphy with pertinent available physical properties.

• Final copies of our soil exploration/test boring logs.

• Recommendations for site preparation and construction of compacted fills.

• Recommended foundation types included deep foundation with helical piles.

• Evaluation and recommendations relative to groundwater control.

1.3 AUTHORIZATION

Our services were provided in accordance with our Proposal No. 25: 6768, dated October 4, 2018, as authorized by Baker Design Build Task Order EVER-235866-ECS-001 on November 19, 2018, and includes the Terms and Conditions of Service outlined between ECS Florida, LLC and Baker Design Build, dated June 4, 2013.

ECS Project No. 25:3404 Page 5

2.0 PROJECT INFORMATION

2.1 PROJECT LOCATION

The subject site is located within the Guy Bradley Flamingo Visitor Center at the Everglades National Park. The project consists of the construction of a new two-story elevator shaft. Figure

2.1.1 below shows the site location.

Figure 2.1.1 Site Location

2.2 PAST SITE HISTORY/USES

ECS reviewed aerial photographs of the subject property and immediate surrounding properties on Google Earth© Historical Imagery databases. The aerial photographs reviewed were dated 1952, 1964, 1995, 1999, 2004, 2007, 2010, 2013, 2014 and 2017.

The 1952 aerial photograph shows the property as undeveloped.

The 1964 aerial photograph shows that the Flamingo visitor center was constructed.

The 1995 through 2017 aerial photographs show no major changes.

2.3 CURRENT SITE CONDITIONS

A site visit was conducted by a staff project engineer from ECS prior to the start of, and during, drilling operations to observe existing site conditions.

The Flamingo visitor center is a two story building within the Everglades National Park, surrounded by wetlands and adjacent to a body of water. The visitor center is currently under renovation and vacant.

ECS Project No. 25:3404 Page 6

2.4 PROPOSED CONSTRUCTION

Based on the provided conceptual site plan, we understand that the project will consist of the construction of a new two-story elevator shaft located within the existing building footprint.

2.4.1 Site Civil Features

Site civil for the site will include cuts and grading for the proposed elevator shaft excavation; fill may be required for bottom of excavation. No planned new stormwater management structures were identified to ECS prior to our exploration. We expect that stormwater management will take advantage of existing urban stormwater structures.

2.4.2 Structural Information/Loads

The following table explains our understanding of the structure design values and assumed loads:

Table 2.4.2.1 Elevator Design Values

SUBJECT DESIGN INFORMATION / EXPECTATIONS

Elevator Footprint +/- 85 S.F. in plan view # of Stories Two-stories above grade, one-story below (shaft) Usage Visitor Center Framing We assume that the elevator shaft will be principally reinforced concrete Design Loads Assumed 100 kips (Full Dead and Live) maximum Lowest Finish Floor Elevation

Assumed -0.5 ft elevation (four feet below land surface)

Column Spacing Assumed approximately 10 x 10 feet

ECS Project No. 25:3404 Page 7

3.0 FIELD EXPLORATION

3.1 FIELD EXPLORATION PROGRAM

The field exploration was planned with the objective of characterizing the project site in general geotechnical and geological terms and to evaluate subsequent field and laboratory data to assist in the determination of geotechnical recommendations for the proposed elevator.

3.1.1 Test Borings

The subsurface conditions were explored by drilling two Standard Penetration Testing (SPT) soil test borings. Boring locations were identified in the field by ECS personnel using GPS techniques and visually estimated distances and relationships to existing site features prior to mobilization of our drilling equipment. Due to limited site access, our soil test borings were performed outside of the existing building. The approximate as-drilled boring locations are shown on the Boring Location Diagram in Appendix A. Ground surface elevations used for our report are approximate based on information obtained from Google Earth©.

A truck-mounted drill rig was utilized to drill the SPT soil test borings. Drilling fluid was used in this process to prevent boreholes from collapsing. SPT borings were generally advanced to depths of 30 feet below the existing ground surface within the proposed building footprint.

Standard penetration tests (SPTs) were conducted in the borings at regular intervals in general accordance with ASTM D 1586. Small representative samples were obtained during these tests and were used to classify the soils encountered. The standard penetration resistances obtained provide a general indication of soil shear strength and compressibility.

3.2 REGIONAL/SITE GEOLOGY

South Florida region is located on the southern flank of Florida Plateau, a stable, carbonate platform on which thick deposits of limestones, dolomites, and evaporates have accumulated.

The general geology of the upper 200 feet of this platform within the area of South Florida where the proposed project is to be located is composed predominantly of limestone and quartz sand.

The two geological formations that usually are encountered from top to bottom within Miami- Dade County are: Miami Limestone and Holocene Sediments.

The following Table describes the generalized stratigraphic column of the general local geology and subsurface materials that may be associated with the geologic units also shown:

ECS Project No. 25:3404 Page 8

Table 3.2.1 Local Geology

Geologic Formation Subsurface Materials

Miami Limestone (Qm) Oolitic Limestone (small round grains usually of calcium carbonate cemented with sand) with Uncemented Sand.

Holocene Sediments (Qh) Occur near the present coastline at elevations generally less than five feet (1.5 meters). The sediments include quartz sands, carbonate sands and muds, and organics.

Geologic Formation details for Table 3.2.1 obtained from the Florida Department of Environmental Protection website, http://www.dep.state.fl.us/geology/gisdatamaps/state_geo_map.htm

The following Figure 3.2.1 presents the regional geological map and approximate site location.

Figure 3.2.1 South Florida Geological Map

Geologic map for Figure 3.2.1 obtained from the Florida Department of Environmental Protection website, http://www.dep.state.fl.us/geology/gisdatamaps/state_geo_map.htm

Site

Homestead

ECS Project No. 25:3404 Page 9

3.3 FEMA FLOOD MAPPING

Based on a review of the FEMA Flood Map 12087C067SK dated February 18, 2005, for the project site area, the property is located within an area designated as Zone VE (EL 16 Feet), which indicates high-risk coastal areas with a 1% or greater chance of flooding and an additional hazard associated with storm waves. These areas have a 26% chance of flooding over the life of a 30-year mortgage. Base flood elevations derived from detailed analyses are shown at selected intervals within these zones in figure below. A copy of the FEMA Flood Map is included in Appendix B attached.

Figure 3.3.1 Site Flood Mapping

Flood map for Figure 3.3.1 obtained from FEMA Flood Map Service Center;

https://msc.fema.gov/portal/home

3.4 SUBSURFACE CHARACTERIZATION

The subsurface conditions encountered in our geotechnical exploration were generally consistent with published geological mapping. Table 3.4.1 below shows surface stratigraphy and the following sections provide generalized characterizations of the soil strata encountered during our subsurface exploration. At the time our exploration was performed, a topographic survey was not provided to ECS. Google Earth© was used to estimate surface elevations. For subsurface information at a specific location, refer to the Boring Logs in Appendix B.

https://msc.fema.gov/portal/home

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Table 3.4.1 Subsurface Stratigraphy Approximate Depth Range

(ft)

Approximate Elevation

(ft)(2)

Stratum Description Ranges of SPT(1) N-values

(bpf)

0 – 0.5 EL +3.0 to +2.5

Surface Cover

Asphalt [0.0 to 1.5”] underlain by Crushed Limestone Base [0.5” – 0.5’];

Topsoil [0.0 – 0.5’]

0.5 – 2.0 EL +2.5 to +1.5 I (SP) SAND, With Crushed Limestone, Moist, Medium Dense 13 - 18

2.0 - 10.0 EL +1.5 to -7.0 II (CL) CLAY, With Sand, Moist to Saturated, Soft to Medium Stiff 2 - 6

10.0 – 30.0 EL -7.0 to -

26.5 III WEATHERED LIMESTONE, Saturated, Medium

Dense to Very Dense 16 – 50/2

Notes: (1) Standard Penetration Test

(2) Please note that the ground surface elevations were not surveyed by a licensed surveyor; these elevations are approximate based Google Earth©.

3.5 GROUNDWATER OBSERVATIONS

Water levels were measured in our borings as noted on the soil boring logs in Appendix B.

Groundwater depths measured at the time of drilling were approximately 3.0 to 4.3 feet below ground surface (or EL. +0.5 to -1.0 feet); consider elevation approximate. No further water measurements were conducted after drilling was finished. Variations in the long-term water table may occur as a result of changes in low and high tide, precipitation, evaporation, surface water runoff, construction activities, and other factors. Based upon our interpretation of the boring data, it appears that the seasonal high groundwater level can be found at a depth of one to two feet (or EL. +2.5 to +1.0 feet); consider elevation approximate.

Please note that the ground surface elevations were not surveyed by a licensed surveyor.

Elevations used in our report are approximate based on information obtained for Google Earth©.

ECS Project No. 25:3404 Page 11

4.0 LABORATORY TESTING

The laboratory testing performed by ECS for this project consisted of selected tests performed on samples obtained during our field exploration operations. The following paragraphs briefly discuss the results of the completed laboratory testing program. Classification and index property tests were performed on representative soil samples obtained from the test borings in order to aid in classifying soils according to the Unified Soil Classification System and to quantify and correlate engineering properties.

An experienced geotechnical engineer visually classified each soil sample from the test borings on the basis of texture and plasticity in accordance with the Unified Soil Classification System (USCS) and ASTM D-2488 (Description and Identification of Soils-Visual/Manual Procedures). After classification, the geotechnical engineer grouped the various soil types into the major zones noted on the boring logs in Appendix B. The group symbols for each soil type are indicated in parentheses before the soil descriptions on the boring logs. The stratification lines designating the interfaces between earth materials on the boring logs are approximate; in situ, the transitions may be gradual.

Laboratory testing included one Wash #200 sieve analysis and moisture content test on a sample obtained from the Boring B-2 (two to four feet bls) indicating approximately 91.4 percent of the soil at the indicated depth was fine particles passing a number 200 sieve, and the moisture contents of the soil at the indicated depths are approximately 49.8 percent, as indicated on the attached Boring Logs.

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5.0 DESIGN RECOMMENDATIONS

5.1 BUILDING DESIGN

The following sections provide recommendations for foundation design for the proposed elevator structure.

2018 IBC states that construction within coastal high hazard areas must be designed in accordance with section ASCE 24. ASCE 24 states that buildings within these areas must be supported on piles, drilled shafts, caissons, or other deep foundations.

Based on the sites location within a VE high-hazard coastal area flood zone (VE EL 16 Feet), and due to limited available work space, we are recommending that the planned two-story above grade elevator structure be supported by a deep foundation system consisting of helical piles.

5.1.1 Helical Piles

We recommend that embedment depth of the helices be a minimum of 20 feet below the assumed bottom elevation of the elevator (assumed approximately EL -1.5 feet) in order to reach the dense sand layer encountered during our exploration. In evaluating our design, we have provided helical pile capacity for evaluation and selection by the project structural engineer, as indicated within the table below:

Table 5.1.1.1 Recommended Helical Pile Capacities

Pile Type Helix Size (inches)

Embedment Depth (feet)

Approximate Embedment

Elevation (+/- ft)

Helical Pile Capacity

(Kips)

Helical

RS2875.262

Helix Gr: 50

THK: 1/2”

14”-12”-10” Helices

23 -23.0 20

It should be noted that the approximate helix embedment depth/elevation is referenced from the assumed bottom elevation of basement. It is also noted that the allowable pile capacity presented in the preceding table is based on a minimum embedment depth of 23 feet below the bottom elevation of the elevation shaft, with a safety factor of two. Total pile settlements are anticipated to be less than 0.5 inches; that is, pile movement required to mobilize soil resistance (approximately 0.15 to 0.25 inches) plus pile shortening resulting from longitudinal elastic compression or elongation. These settlements will occur more or less immediately upon application of the service loads. Long term settlements after that time are estimated to be negligible, unless substantial additional loads are applied.

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Prior to ordering all helical piles for the subject project, we recommend that approximately two test helical piles be installed in order to confirm lengths and helices configurations. The capacity of test piles is to be confirmed by means of measuring and observing the installation torque.

Additionally, we recommend that each helical production pile be monitored for installation torques.

The allowable axial or uplift capacity of an individual pile is related to the installation torque obtained from a gauge reading during installation. Torque installation requirements are based on the use of the CHANCE Helical Piles/Anchors type square shaft (SS) and round shaft (RS).

Extension sections are added as the pile is installed until the pile encounters soil with adequate bearing capacity based on the torque reading. The actual length and bearing capacity of the helical pile should be verified by field observations at the time of installation, by the Geotechnical Engineer or qualified representative. The piles should be advanced until the desired capacity is achieved and all installation logs should be provided to the Geotechnical Engineer at the time of installation.

Lateral capacities of vertical helical piles are minimal and are typically not considered suitable for lateral resistance alone. In the case of the existing structure, it is anticipated that the passive/active earth pressures at the shallow foundations will provide the appropriate lateral resistance for the structure. In the event that earth pressures are determined to provide insufficient lateral support, then battering of the helical piles or a grouted column may be evaluated for increasing the lateral capacity of pile groups.

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5.1.2 Soil Parameters

Based on the geotechnical analyses and SPT soil test boring data, we recommend using the parameters indicated on Table 5.1.2.1 below. The following parameters are included: soil unit weights, angle of internal friction, and earth pressure coefficients. It should be noted that if your design analysis requires effective stress parameters for unit weight, subtract 62.4 pounds per cubic feet (pcf) from the unit weights below the groundwater level for the unit weight to account for buoyant stresses in soil.

Table 5.1.2.1 Soil Parameters Boring

No.

Depth

(Feet)

SPT “N”

Range

(Blows

/Foot)

Soil Classification Approx. Soil Unit Weight (pcf)

Soil Angle of Frictio n (°)

Eath Preassure Coefficients

X Satur. X Submer. Active (Ka)

Passive (Kp)

B-1

0.00 – 2.0 18 (SP) SAND, Crushed Limestone

105 42.6 34 0.28 3.54

2.0 – 10.0 2 – 4 (CL) Clay with Sand* 90 27.6 22 - -

10.0 – 17.5 34 WEATHERED

LIMESTONE

120 57.6 39 0.23 4.40

17.5 – 22.5 16 WEATHERED

LIMESTONE

105 42.6 33 0.29 3.39

22.5 – 30.0 50/1 – 50/2 WEATHERED

LIMESTONE

140 77.6 42 0.20 5.04

B-2

0.0 – 2.0 13 (SP) SAND, Crushed Limestone

105 42.6 32 0.31 3.25

2.0 – 10.0 2 – 6 (CL) Clay with Sand* 90 27.6 22 - -

10.0 – 22.5 25 – 28 WEATHERED

LIMESTONE

115 52.6 37 0.25 4.02

22.5 – 30.0 50/1 – 50/2 WEATHERED

LIMESTONE

140 77.6 42 0.20 5.04

(*) Undrained strength is approximately 0.75 – 1.0 ksf.

ECS Project No. 25:3404 Page 15

6.0 SITE CONSTRUCTION RECOMMENDATIONS

6.1 SUBGRADE PREPARATION

6.1.1 Demolition

The site is developed with an existing building. Parts of the structure located within the proposed elevator shaft area will be demolished and all debris is to be removed from the site; debris material cannot be used as any type of fill on site. All below-grade objects such as foundations, utilities, etc. are to be excavated, removed transported offsite. Any excavations to remove existing below-grade objects, is to be backfilled with structural fill and compacted per compaction requirements of this report so as to provide a stable subgrade.

6.1.2 Stripping and Grubbing

The subgrade preparation should consist of stripping all concrete, asphalt, vegetation, rootmat, topsoil, and any other soft or unsuitable materials from the ten-foot expanded elevator limits.

ECS should be called on to verify that topsoil and unsuitable surficial materials have been completely removed prior to the placement of Structural Fill or construction of structures.

6.1.3 Compaction

After removing all unsuitable surface materials, cutting to the proposed grade, and prior to the placement of any structural fill or other construction materials, the exposed subgrade should be examined by the Geotechnical Engineer or authorized representative. The exposed subgrade should be thoroughly compacted with previously approved construction equipment such as a tamper rod. The areas subject to compaction should be traversed by the equipment in two perpendicular (orthogonal) directions with overlapping passes of the tamper under the observation of the Geotechnical Engineer or authorized representative. This procedure is intended to assist in identifying any localized yielding materials. In the event that unstable or “pumping” subgrade is identified by the compaction, those areas should be marked for repair prior to the placement of any subsequent structural fill or other construction materials. Methods of repair of unstable subgrade, such as undercutting or moisture conditioning or chemical stabilization, should be discussed with the Geotechnical Engineer to determine the appropriate procedure with regard to the existing conditions causing the instability. A test pit(s) may be excavated to explore the shallow subsurface materials in the area of the instability to help in determined the cause of the observed unstable materials and to assist in the evaluation of the appropriate remedial action to stabilize the subgrade.

6.1.4 Site Temporary Dewatering

General Groundwater Conditions: Groundwater observations are described in Section 3.5 of this report. The depth at which groundwater is present on the site varies with surface elevation. In low-lying areas the presence of groundwater is more pronounced. Soils at contact with groundwater levels were very moist to wet. In most cases, moisture then decreased with depth.

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Based upon our subsurface exploration at this site, as well as significant experience on sites in nearby areas of similar geologic setting, we believe construction dewatering at this site will be needed within the elevator shaft assumed five feet excavation. Dewatering recommendations and design can be provided once plans are available.

A well point system may be required as a temporary dewatering system or the use of conventional submersible pumps directly in the excavation to remove water from the excavation can be considered. If temporary sump pits are used, we recommend a one foot over excavation within the planned excavation subgrade be prepared. The submersible pump should be place within the over excavation zone and surrounded by FDOT No. 57 Stone. We recommend continuous dewatering of the excavations using electric pumps or manned gasoline pumps.

6.1.5 Subgrade Stabilization

Subgrade Compaction: Upon completion of subgrade documentation, the exposed subgrade within the ten-foot expanded elevator limit should be moisture conditioned to within +/- two percent of the soil’s optimum moisture content and be compacted with suitable equipment (tamper rod) to a depth of ten inches. Subgrade compaction within the elevator shaft limits should be to a dry density of at least 98 percent of the Modified Proctor maximum dry density (ASTM D1557). Beyond these areas, compaction of at least 95 percent should be achieved. ECS should be called on to document that proper subgrade compaction has been achieved.

Subgrade Compaction Control: The expanded limits of the proposed elevator area should be well defined. Field density testing of subgrades should be taken in a minimum of two opposing quadrants of the excavation.

Subgrade Stabilization: In some areas, particularly low-lying, wet areas of the site, undercutting of excessively soft materials may be considered inefficient. In such areas the use of a reinforcing geotextile or geogrid might be employed, under the advisement of ECS. Suitable stabilization materials may include medium duty woven geotextile fabrics or geogrids. The suitability and employment of reinforcing or stabilization products should be determined in the field by ECS personnel, in accordance with project specifications.

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6.2 EARTHWORK OPERATIONS

6.2.1 Structural Fill Materials

Product Submittals: Prior to placement of Structural Fill, representative bulk samples (about 50 pounds) of on-site and off-site borrow should be submitted to ECS for laboratory testing, which will include, natural moisture content, grain-size distribution, and moisture-density relationships for compaction. Import materials should be tested prior to being hauled to the site to determine if they meet project specifications.

Satisfactory Structural Fill Materials: Materials satisfactory for use as Structural Fill should consist of inorganic soils classified as SW, SP, GW, GP, GM and GC, or a combination of these group symbols, per ASTM D 2487. The materials should be free of organic matter, debris, and should contain no particle sizes greater than four inches in the largest dimension. Open graded materials, such as Gravels (GW and GP), which contain void space in their mass should not be used in structural fills unless properly encapsulated with filter fabric.

Unsatisfactory Materials: Unsatisfactory fill materials include materials which to not satisfy the requirements for suitable materials, as well as topsoil and organic materials (Pt, OH, OL), Silt (MH, ML), and Clay (CH, CL).

6.2.2 Compaction

Structural Fill Compaction: Structural Fill within the expanded elevator limits should be placed in maximum 12-inch loose lifts, moisture conditioned as necessary to within +/- two percent of the soil’s optimum moisture content, and be compacted with suitable equipment to a dry density of at least 98 percent of the Modified Proctor maximum dry density (ASTM D1557). Beyond these areas, compaction of at least 95 percent should be achieved. ECS should be called on to document that proper fill compaction has been achieved.

Fill Compaction Control: The expanded limits of the proposed elevator construction area should be well defined, at the time of fill placement. Grade controls should be maintained throughout the filling operations. All filling operations should be observed on a full-time basis by a qualified representative of the construction testing laboratory to determine that the minimum compaction requirements are being achieved. Field density testing of fills should be performed in two opposing quadrants of excavation per lift.

Compaction Equipment: Compaction equipment suitable to the soil type being compacted should be used to compact the subgrades and fill materials. A vibratory steel drum roller or tamper rod should be used for compaction of coarse-grained soils (Sands) as well as for sealing compacted surfaces.

Fill Placement Considerations: Fill materials should not be placed on excessively wet soils.

Excessively wet soils or aggregates should be scarified, aerated, and moisture conditioned.

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At the end of each work day, all fill areas should be graded to facilitate drainage of any precipitation and the surface should be sealed by use of a smooth-drum roller to limit infiltration of surface water. During placement and compaction of new fill at the beginning of each workday, the Contractor may need to scarify existing subgrades to a depth on the order of four inches so that a weak plane will not be formed between the new fill and the existing subgrade soils.

Drying and compaction of wet soils is typically difficult during the rainy season. Accordingly, earthwork should be performed during the drier times of the year, if practical. Proper drainage should be maintained during the earthwork phases of construction to prevent ponding of water which has a tendency to degrade subgrade soils. Alternatively, if these soils cannot be stabilized by conventional methods as previously discussed, additional modifications to the subgrade soils such as cement stabilization may be utilized to adjust the moisture content. If cement is utilized to control moisture contents and/or for stabilization, regular Type 1 cement can be used. The construction testing laboratory should evaluate proposed cement soil modification procedures, such as quantity of additive and mixing and curing procedures, before implementation. The contractor should be required to minimize dusting or implement dust control measures, as required.

Fill material should be placed in horizontal lifts in confined areas such as the elevator shaft, portable compaction equipment and thin lifts of three inches to four inches may be required to achieve specified degrees of compaction.

We recommend that the grading contractor have equipment on site during earthwork for both drying and wetting fill soils. We do not anticipate significant problems in controlling moisture however moisture control should be considered.

6.3 GENERAL CONSTRUCTION CONSIDERATIONS

Moisture Conditioning: During the wetter periods of the year, delays and additional costs should be anticipated. At these times, reduction of soil moisture may need to be accomplished by a combination of mechanical manipulation and the use of chemical additives, such as lime or cement, in order to lower moisture contents to levels appropriate for compaction. Alternatively, during the drier times of the year, such as the summer months, moisture may need to be added to the soil to provide adequate moisture for successful compaction according to the project requirements.

Excavation Safety: Cuts or excavations associated with utility excavations may require forming or bracing, slope flattening, or other physical measures to control sloughing and/or prevent slope failures. Contractors should be familiar with applicable OSHA codes to ensure that adequate protection of the excavations and trench walls is provided.

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All excavations and slopes should be made and maintained in accordance with OSHA excavation safety standards. The contractor is solely responsible for designing and constructing stable, temporary excavations and slopes and should shore, slope, or bench the sides of the excavations and slopes as required to maintain stability of both the excavation sides and bottom. The contractor’s responsible person, as defined in 29 CFR Part 1926, should evaluate the soil exposed in the excavations as part of the contractor’s safety procedures. In no case should slope height, slope inclination, or excavation depth, including utility trench excavation depth, exceed those specified in local, state, and federal safety regulations. ECS is providing this information solely as a service to our client. ECS is not assuming responsibility for construction site safety or the contractor’s activities; such responsibility is not being implied and should not be inferred.

Erosion Control: The surface soils may be erodible. Therefore, the Contractor should provide and maintain good site drainage during earthwork operations to maintain the integrity of the surface soils. All erosion and sedimentation controls should be in accordance with sound engineering practices and local requirements.

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7.0 CLOSING

ECS has prepared this report of findings, evaluations, and recommendations to guide geotechnical-related design and construction aspects of the project.

The description of the proposed project is based on information provided to ECS by Baker Design Build; if any of this information is inaccurate such as our assumed structural loads, or excavation depth, either due to our interpretation of the documents provided or site or design changes that may occur later, ECS should be contacted immediately in order that we can review the report in light of the changes and provide additional or alternate recommendations as may be required to reflect the proposed construction.

We recommend that ECS be allowed to review the project’s plans and specifications pertaining to our work so that we may ascertain consistency of those plans/specifications with the intent of the geotechnical report.

Field observations, monitoring, and quality assurance (QA) testing during earthwork and foundation installation are an extension of and integral to the geotechnical design recommendation. We recommend that the owner retain these QA services and that ECS be allowed to continue our involvement throughout these critical phases of construction to provide general consultation as issues arise. ECS is not responsible for the conclusions, opinions, or recommendations of others based on the data in this report.

APPENDIX A – Drawings & Reports

Site Location Diagram Boring Location Diagram Geologic Map FEMA Flood Map

10/16/2018

Service Layer Credits: Esri, HERE, Garmin, © OpenStreetMap contributors

²

ENGINEER

SCALE

25:3404

PROJECT NO.

SHEET

DATE

JNGSITE VICINITY DIAGRAM

GUY BRADLEY FLAMINGO VISITOR CENTER

ELEVATOR

1 FLAMINGO LODGE HIGHWAY, HOMESTEAD, FL

BAKER DESIGN BUILD

0 600300 Feet

1 " = 300 '

OCTOBER

ENGINEER

PROJECT NO.

DATE

LER/JA

BORING LOCATION DIAGRAM

FLAMINGO VISITOR CENTER

1 FLAMINGO LODGE HIGHWAY

BAKER DESIGN BUILD

30’ SPT BORINGS B-1 – B-2

LEGEND

B-1 B-2

SCALE IN FEET

20 0

GEOLOGIC MAP

FIGURE 3.2.1

OBTAINED FROM THE UNITED STATE GEOLOFICAL SURVEY PUBLICATIONS

WAREHOUSE WEBISTE

https://sofia.er.usgs.gov/publications/maps/florida_geology/#sections

Site

HOMESTEAD

USGS The National Map: Orthoimagery. Data refreshed October 2017.

National Flood Hazard Layer FIRMette

0 500 1,000 1,500 2,000250 Feet

Ü

°5

5'

.8 9"

W

25°8'43.03"N

80°55'8.43"W

25°8'10.46"N

SEE FIS REPORT FOR DETAILED LEGEND AND INDEX MAP FOR FIRM PANEL LAYOUT

SPECIAL FLOOD

HAZARD AREAS

Without Base Flood Elevation (BFE) Zone A, V, A99

With BFE or Depth Zone AE, AO, AH, VE, AR Regulatory Floodway

0.2% Annual Chance Flood Hazard, Areas of 1% annual chance flood with average depth less than one foot or with drainage areas of less than one square mile Zone X Future Conditions 1% Annual Chance Flood Hazard Zone X Area with Reduced Flood Risk due to Levee. See Notes. Zone X Area with Flood Risk due to Levee Zone D

NO SCREEN Area of Minimal Flood Hazard Zone X

Area of Undetermined Flood Hazard Zone D

Channel, Culvert, or Storm Sewer Levee, Dike, or Floodwall

Cross Sections with 1% Annual Chance

17.5 Water Surface Elevation

Coastal Transect

Coastal Transect Baseline Profile Baseline Hydrographic Feature

Base Flood Elevation Line (BFE)

Effective LOMRs

Limit of Study Jurisdiction Boundary

Digital Data Available No Digital Data Available Unmapped

This map complies with FEMA's standards for the use of digital flood maps if it is not void as described below.

The basemap shown complies with FEMA's basemap accuracy standards The flood hazard information is derived directly from the authoritative NFHL web services provided by FEMA. This map was exported on 10/25/2018 at 4:14:13 PM and does not reflect changes or amendments subsequent to this date and time. The NFHL and effective information may change or become superseded by new data over time.

This map image is void if the one or more of the following map elements do not appear: basemap imagery, flood zone labels, legend, scale bar, map creation date, community identifiers, FIRM panel number, and FIRM effective date. Map images for unmapped and unmodernized areas cannot be used for regulatory purposes.

Legend

OTHER AREAS OF

FLOOD HAZARD

OTHER AREAS

GENERAL

STRUCTURES

OTHER

FEATURES

MAP PANELS

1:6,000

B 20.2

The pin displayed on the map is an approximate point selected by the user and does not represent an authoritative property location.

APPENDIX B – Field Operations

Reference Notes for Boring Logs Boring Logs B-1 through B-2

Reference Notes for Boring Logs (03-22-2017) © 2017 ECS Corporate Services, LLC. All Rights Reserved

COHESIVE SILTS & CLAYS

UNCONFINED

COMPRESSIVE

STRENGTH, QP

SPT

(BPF)

CONSISTENCY

(COHESIVE)

<0.25 <3 Very Soft

0.25 - <0.50 3 - 4 Soft

0.50 - <1.00 5 - 8 Firm

1.00 - <2.00 9 - 15 Stiff

2.00 - <4.00 16 - 30 Very Stiff

4.00 - 8.00 31 - 50 Hard

>8.00 >50 Very Hard

GRAVELS, SANDS & NON-COHESIVE SILTS

SPT

DENSITY

<5 Very Loose

5 - 10 Loose

11 - 30 Medium Dense

31 - 50 Dense

>50 Very Dense

REFERENCE NOTES FOR BORING LOGS

Classifications and symbols per ASTM D 2488-09 (Visual-Manual Procedure) unless noted otherwise.

To be consistent with general practice, “POORLY GRADED” has been removed from GP, GP-GM, GP-GC, SP, SP-SM, SP-SC soil types on the boring logs.

Non-ASTM designations are included in soil descriptions and symbols along with ASTM symbol [Ex: (SM-FILL)].

Typically estimated via pocket penetrometer or Torvane shear test and expressed in tons per square foot (tsf).

Standard Penetration Test (SPT) refers to the number of hammer blows (blow count) of a 140 lb. hammer falling 30 inches on a 2 inch OD split spoon sampler required to drive the sampler 12 inches (ASTM D 1586). “N-value” is another term for “blow count” and is expressed in blows per foot (bpf).

The water levels are those levels actually measured in the borehole at the times indicated by the symbol. The measurements are relatively reliable when augering, without adding fluids, in granular soils. In clay and cohesive silts, the determination of water levels may require several days for the water level to stabilize. In such cases, additional methods of measurement are generally employed.

Minor deviation from ASTM D 2488-09 Note 16.

Percentages are estimated to the nearest 5% per ASTM D 2488-09.

RELATIVE

AMOUNT

COARSE

GRAINED

FINE

GRAINED

Trace <5 <5

Dual Symbol (ex: SW-SM)

10 10

With 15 - 20 15 - 25

Adjective (ex: “Silty”)

>25 >30

WATER LEVELS

WL Water Level (WS)(WD)

(WS) While Sampling

(WD) While Drilling

SHW Seasonal High WT

ACR After Casing Removal

SWT Stabilized Water Table

DCI Dry Cave-In

WCI Wet Cave-In

DRILLING SAMPLING SYMBOLS & ABBREVIATIONS

SS Split Spoon Sampler PM Pressuremeter Test

ST Shelby Tube Sampler RD Rock Bit Drilling

WS Wash Sample RC Rock Core, NX, BX, AX

BS Bulk Sample of Cuttings REC Rock Sample Recovery %

PA Power Auger (no sample) RQD Rock Quality Designation %

HSA Hollow Stem Auger

PARTICLE SIZE IDENTIFICATION

DESIGNATION PARTICLE SIZES

Boulders 12 inches (300 mm) or larger

Cobbles 3 inches to 12 inches (75 mm to 300 mm)

Gravel: Coarse ¾ inch to 3 inches (19 mm to 75 mm)

Fine 4.75 mm to 19 mm (No. 4 sieve to ¾ inch)

Sand: Coarse 2.00 mm to 4.75 mm (No. 10 to No. 4 sieve)

Medium 0.425 mm to 2.00 mm (No. 40 to No. 10 sieve)

Fine 0.074 mm to 0.425 mm (No. 200 to No. 40 sieve)

Silt & Clay (“Fines”) <0.074 mm (smaller than a No. 200 sieve)

MATERIAL

1,2

ASPHALT

CONCRETE

GRAVEL

TOPSOIL

VOID

BRICK

AGGREGATE BASE COURSE

FILL

MAN-PLACED SOILS

GW WELL-GRADED GRAVEL

gravel-sand mixtures, little or no fines

GP POORLY-GRADED GRAVEL

gravel-sand mixtures, little or no fines

GM SILTY GRAVEL

gravel-sand-silt mixtures

GC CLAYEY GRAVEL

gravel-sand-clay mixtures

SW WELL-GRADED SAND

gravelly sand, little or no fines

SP POORLY-GRADED SAND

gravelly sand, little or no fines

SM SILTY SAND

sand-silt mixtures

SC CLAYEY SAND

sand-clay mixtures

ML SILT

non-plastic to medium plasticity

MH ELASTIC SILT

high plasticity

CL LEAN CLAY

low to medium plasticity

CH FAT CLAY

OL ORGANIC SILT or CLAY non-plastic to low plasticity

OH ORGANIC SILT or CLAY

PT PEAT

highly organic soils

-5

-10

-15

-20

-25

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

S-9

SS

SS

SS

SS

SS

SS

SS

SS

SS

Asphalt Thickness [1.50"] (SP) SAND, Crushed Limestone, Gray, Moist, Medium Dense (CL) CLAY, Gray, Moist to Saturated, Soft to Very Soft

WEATHERED LIMESTONE, Gray, Saturated, Medium Dense to Very Dense

END OF BORING @ 30.00'

50/1

50/2

50/1

50/2

CLIENT

Baker Design Build

Job #:

25:3404

BORING #

B-1

SHEET

PROJECT NAME

Guy Bradley Flamingo Visitor Center Elevator

ARCHITECT-ENGINEER

Jose N. Gomez

SITE LOCATION

1 Flamingo Lodge Highway, Homestead, Dade County, FL

NORTHING

9122500.014

EASTING

1665452.76

STATION

THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL TYPES. IN-SITU THE TRANSITION MAY BE GRADUAL.

WL 3.0 WS WD BORING STARTED 10/15/18 CAVE IN DEPTH

WL(SHW) 1.0 WL(ACR) BORING COMPLETED 10/15/18 HAMMER TYPE Auto

WL RIG Truck FOREMAN DRILLING METHOD Mud RotaryDRILLING METHOD Mud Rotary

D E

P T

H

F T

S A

M P

L E

N O

S A

M P

L E

T Y

P E

S A

M P

L E

D

IS

T

(I N

R E

C O

V E

R Y

IN

SURFACE ELEVATION

DESCRIPTION OF MATERIAL

W A

T E

R L

E V

E L S

E L E

V A

T

IO

N

F T

B L O

W S

/6

10 20 30 40 50+

20% 40% 60% 80% 100%

1 2 3 4 5+

ENGLISH UNITS

BOTTOM OF CASING LOSS OF CIRCULATION

CALIBRATED PENETROMETER TONS/FT2

PLASTIC

LIMIT %

WATER

CONTENT %

LIQUID

LIMIT %

ROCK QUALITY DESIGNATION & RECOVERY

RQD% REC.%

STANDARD PENETRATION

BLOWS/FT+3.3 ft (Approximately)

-5

-10

-15

-20

-25

S-1

S-2

S-3

S-4

S-5

S-6

S-7

S-8

S-9

SS

SS

SS

SS

SS

SS

SS

SS

SS

Topsoil Thickness [6.00"] (SP) SAND, With Crushed Limestone and Trace Roots, Brown, Moist, Medium Dense (CL) CLAY, Trace Crushed Limestone, Gray, Moist to Saturated, Firm to Very Soft

[Wash#200: 91.4%]

WEATHERED LIMESTONE, Gray, Saturated, Medium Dense to Very Dense

END OF BORING @ 30.00'

50/1

50/2

49.8

50/1

50/2

CLIENT

Baker Design Build

Job #:

25:3404

BORING #

B-2

SHEET

PROJECT NAME

Guy Bradley Flamingo Visitor Center Elevator

ARCHITECT-ENGINEER

Jose N. Gomez

SITE LOCATION

1 Flamingo Lodge Highway, Homestead, Dade County, FL

NORTHING

9122506.576

EASTING

1665419.95

STATION

THE STRATIFICATION LINES REPRESENT THE APPROXIMATE BOUNDARY LINES BETWEEN SOIL TYPES. IN-SITU THE TRANSITION MAY BE GRADUAL.

WL 4.3 WS WD BORING STARTED 10/15/18 CAVE IN DEPTH

WL(SHW) 2.3 WL(ACR) BORING COMPLETED 10/15/18 HAMMER TYPE Auto

WL RIG Truck FOREMAN DRILLING METHOD Mud RotaryDRILLING METHOD Mud Rotary

D E

P T

H

F T

S A

M P

L E

N O

S A

M P

L E

T Y

P E

S A

M P

L E

D

IS

T

(I N

R E

C O

V E

R Y

IN

SURFACE ELEVATION

DESCRIPTION OF MATERIAL

W A

T E

R L

E V

E L S

E L E

V A

T

IO

N

F T

B L O

W S

/6

10 20 30 40 50+

20% 40% 60% 80% 100%

1 2 3 4 5+

ENGLISH UNITS

BOTTOM OF CASING LOSS OF CIRCULATION

CALIBRATED PENETROMETER TONS/FT2

PLASTIC

LIMIT %

WATER

CONTENT %

LIQUID

LIMIT %

ROCK QUALITY DESIGNATION & RECOVERY

RQD% REC.%

STANDARD PENETRATION

BLOWS/FT+3.3 ft (Approximately)

APPENDIX C – Laboratory Test

Laboratory Testing Results

ECS Florida, LLC West Palm Beach, FL

Laboratory Testing Summary

Project No.: 25: 3404 Guy Bradley Flamingo Visitor Center Printed on: October 25, 2018

Project Engineer: Lucrèce E. Regisme Principal Engineer: Jose N. Gómez, P.E., D.GE Summary By: Jeff Anosier

B-2 S-3 2.0 - 4.0 CL 49.8 91.4

Notes:

Definitions:

Project Name:

MC: Moisture Content, Soil Types: USCS ( Unified Soil Classification System), OC: Organic Content.

Boring Number

Sample Number Depth (feet)

1. ASTM D 2487, 2. ASTM D 2216, 3. ASTM D 1140

Soil Type [1.] MC (%) [2.] Wash No.200 Sieve (%) [3.]

6.3 General Construction Considerations