Attachment C - Geotechnical Report.pdf

Pacifica Engineering Services | 6835 International Center Blvd., STE 1 | Fort Myers, Florida 33912 | 561-419-8460 www.pacificaes.com | Florida Certification of Authorization License No. 32328

February 10, 2025

HSQ Group, Inc.

1001 Yamato Road, Suite 105 Boca Raton, FL 33431

Attention: Tony Quevedo, P.E.

Email: tony@hsqgroup.net Phone: (561) 239-3653

Re: Report of Geotechnical Engineering Services Seminole Tribe of Florida Canopy 2 Seminole Tribe of Florida Big Cypress Reserve PACIFICA Project No.: 320-25483

Dear Mr. Quevedo:

Pacifica Engineering Services, LLC. (PACIFICA) has completed a geotechnical engineering study for the above-referenced project. The scope of geotechnical services was completed in general accordance with PACIFICA Proposal for Geotechnical Engineering Services Number 610-12017021 dated January 9, 2024.

PACIFICA appreciates the opportunity to provide geotechnical engineering services on this project and look forward to an opportunity to participate in construction-related aspects of the development. If you have any questions or should additional information, be required, please do not hesitate to contact our office at (561) 491-8460.

Sincerely, Pacifica Engineering Services Florida Certification of Authorization License No. 32328

Marc Restrepo, E.I. Patrick Montgomery, P.E.

Staff Geotechnical Engineer Sr. Geotechnical Engineer

FL License No. 81132

ATTACHMENT C

Seminole Tribe of Florida Canopy 2 PACIFICA Project No. 320-25483 Page i

TABLE OF CONTENTS

1.0 GENERAL PROJECT INFORMATION

2.0 GEOTECHNICAL EXPLORATION

2.1 GEOTECHNICAL BORINGS

2.2 SUBSURFACE & GROUNDWATER CONDITIONS

2.3 USDA SOIL SURVEY

2.4 SEASONAL HIGH GROUND WATER TABLE (SHGWT)

3.0 GEOTECHNICAL CLASSIFICATION

4.0 FOUNDATION RECOMMENDATIONS

4.1 SHALLOW FOUNDATIONS RECOMMENDATIONS

4.2 GROUND FLOOR SLAB RECOMMENDATIONS

5.0 SITE PREPARATION RECOMMENDATIONS

5.1 GENERAL SITE PREPARATION

5.2 DEWATERING RECOMMENDATIONS

5.3 COMPACTION RECOMMENDATIONS

5.4 STRUCTURAL FILL SOILS

5.5 SHALLOW FOUNDATION CONSTRUCTION

6.0 REPORT LIMITATIONS

APPENDIX

USDA Soil Map

Sheet G-1: Report of Core Borings Summary of Laboratory Test Results

PACIFICA Project No.: 320-25483 Page 1

1.0 GENERAL PROJECT INFORMATION

The project is located at the Big Cypress Re-Pump Station within the Seminole Tribe of Florida’s Big Cypress Reservation. We understand the plans for this project include the design and construction of new metal canopies.

Structural loading information was not provided at the time of this report; therefore, PACIFICA has assumed maximum column loads of 50 kips. Similarly, site grading information was not provided and the assumption that existing site grades will be within 2 feet of final site grades has been made.

If any of the information in this report is incorrect or has changed, please notify PACIFICA so that the recommendations presented within may be checked. PACIFICA will not be held responsible if not given the opportunity to check the recommendations once designs have been completed.

2.0 GEOTECHNICAL EXPLORATION

2.1 Geotechnical Borings

Three (3) Standard Penetration Test (SPT) geotechnical borings boring were performed to assess the subsurface conditions. The borings were advanced to a depth of 20 feet with respect to the site grades at the time of the geotechnical exploration. A boring location plan can be found on Sheet 2 of the Appendix.

The SPT borings were performed using a CME-45 truck-mounted geotechnical drilling rig equipped with an automatic hammer utilizing mud rotary drilling techniques. The SPT samples were collected continuously in the upper 10 feet and at 5-foot intervals thereafter until final boring depths were reached.

After the samples were collected in the split barrel sampler they were bagged, labeled, and transported back to the laboratory for description and limited testing. After the geotechnical borings were completed, they were backfilled using access auger cuttings and the ground surface was generally leveled.

2.2 Subsurface & Groundwater Conditions

The individual boring logs included in the appendix show the various soil types and stratifications.

The transition between soil strata may be gradual and not as definitive as it appears on the boring logs. If the contractor cannot determine the soil stratum during construction the geotechnical engineer should be consulted.

The groundwater table was encountered at a depth of 8 feet at the time of the geotechnical exploration. The groundwater table may vary due to rainfall, runoff, droughts or the infiltration rate of the soil and therefore the contractor should verify the groundwater table prior to construction.

2.3 USDA Soil Survey

Based on our review of the Hendry County Area Soil Survey prepared by the United States Department of Agriculture (USDA) Natural Resources Conservation Service (NRCS), the following soil mapping units appear at the project site:

PACIFICA Project No.: 320-25483 Page 2

• 1 – Cypress Lake Sand, 0 to 2 percent slopes

The USDA soil survey map is presented in the Appendix.

2.4 Seasonal High Ground Water Table (SHGWT)

The groundwater depth was measured at the boring locations following the termination of drilling.

Encountered groundwater depths measured in the boreholes are presented in the soil profiles in the Appendix. The groundwater table may vary due to rainfall, runoff, droughts, nearby water control structures, or the infiltration rate of the soil, and therefore the contractor should verify the groundwater table prior to construction.

Seasonal high groundwater levels are expected to be controlled by existing drainage features, the time of year, rainfall events, and water bodies present in the project vicinity. Based on the time of the geotechnical exploration, the groundwater levels have been recorded during the dry season during the month of January 2025. Therefore, the groundwater levels can be 18 to 24 inches higher during the peak of the wet season (October). In South Florida, the peak of the dry season is usually during the month of April when water levels are usually the lowest. We recommend the project design be coordinated with adjacent projects and the SHGWT and Design High Water (DHW) be adjusted accordingly for a smooth transition in roadway and drainage profiles with the adjacent projects. For more accurate measurements of groundwater levels, we recommended the installation of monitoring wells and monitoring groundwater levels throughout the year.

3.0 GEOTECHNICAL CLASSIFICATION

The soil samples taken from the geotechnical borings were taken back to the laboratory and visually reviewed by a geotechnical engineer. The soil samples were classified using the Unified Soil Classification System (USCS) in general accordance with the American Society of Testing and Materials (ASTM) test designation D2487.

4.0 FOUNDATION RECOMMENDATIONS

4.1 Shallow Foundations Recommendations

The proposed canopy may be supported on shallow spread footings/grade beams or monolithic reinforced slab-on-grade foundation system. Prior to placement of the shallow foundations properly compacted in-situ granular soils or structural fill soils should be placed and compacted within the footprint of each shallow foundation. Structural fill backfill classification and compaction requirements shall be followed and are outlined in Section 5.0 of this report.

Shallow foundations, or monolithic reinforced slab-on-grade systems, with an allowable bearing pressure of 2,500 pounds per square foot and placed at a minimum of 1.5 feet below finished floor elevation is recommended for the proposed canopy. In order to prevent punching shear failure, the minimum footings widths for continuous and isolated footings should be 2 feet and 3 feet, respectively. Footings in the canopy should be designed for uplift forces by the structural engineer and appropriate factors of safety should be applied to the anchors in this area to resist these uplift forces.

Designers should use a friction factor of 0.35 for base shearing resistance and values calculated from this shearing resistance should be considered ultimate. Passive earth pressure resistance

PACIFICA Project No.: 320-25483 Page 3 should be computed using an equivalent fluid pressure of 180 pounds per square foot per foot of depth, for granular materials. Additional soil values the designer may require for uplift design are the unit weight and submerged unit weight of the soil, 110 pcf and 48 pcf, respectively.

Settlement estimates were determined based on the assumed structural loads listed in Section

1.0 of this report and the allowable bearing capacity detailed in the beginning of this section.

Please contact PACIFICA if the assumed loads are incorrect. PACIFICA is not responsible nor will be held liable if the assumed loads in this report are inaccurate. Settlement estimates were determined from empirical relationships and based on experience with similar projects. Based on the geotechnical exploration, the required compaction recommendations in this report and the assumed loads listed in Section 1.0, an estimated settlement of 1 inch or less, was calculated.

Differential settlement between adjacent shallow foundations may be approximately ½ the total estimated settlement. Due to the elastic characteristics of granular soils the settlement should be observed as soon as the live loads are applied. These settlements are usually considered to be tolerable for the proposed structure. However, if more stringent settlements are required then PACIFICA should be contacted to revise the recommendations given in this report.

4.2 Ground Floor Slab Recommendations

Ground floor slabs can bear directly on top of compacted structural fill material that is compacted based on requirements in Section 5.0. A modulus of subgrade reaction value of 100 pounds per cubic inch (pci) may be used for design. The underside of the ground floor slab should be lined with a vapor barrier at least 6 mil thick. A friction factor of 0.21 (ultimate) can be used for the soil to vapor barrier interface.

5.0 SITE PREPARATION RECOMMENDATIONS

5.1 General Site Preparation

The results of the field investigation and experience from similar projects have yielded the following recommendations detailed in steps. These steps should be conducted by an experienced contractor adhering to current regulatory standards. It should be noted that these steps should be performed with care to not damage any adjacent structures or any underground utilities.

1) Prior to construction activities on-site underground utilities should be identified and marked in the field. If any of the existing utility lines are in conflict with the proposed construction, then plans should be made to relocate these lines. If the utilities discovered are abandoned or out of service, they should be removed.

2) Topsoil, asphalt, concrete, organic soils, unsuitable material, or any other debris should be stripped to expose in-situ soils. If any old foundations from previous structures are encountered, then they should be removed in their entirety. If deep foundations are encountered the geotechnical engineer should be retained to assess the impact on the proposed structures and to make recommendations on mitigation.

3) The exposed on-site soils in the building(s) footprint should be properly compacted per the recommendations in the section entitled Compaction Recommendations. The compaction should extend 5 feet beyond the perimeter of the building.

4) Any unsuitable material or debris encountered should be removed and replaced with structural fill.

PACIFICA Project No.: 320-25483 Page 4

5) Any fill needed to bring up the site to the proper elevation, including any reference to structural fill in this report, should adhere to the recommendations given in the section entitled Structural Fill Soils.

6) A representative of the geotechnical engineer should be present and properly document these activities.

7) Any other geotechnical-related questions should be directed to the geotechnical engineer of record.

The contractor should adhere and be aware of all OSHA and any regulatory standards during construction activities. The contractor is responsible and held solely liable if these standards are not upheld.

5.2 Dewatering Recommendations

Dewatering may be required on this site if deeper excavations are warranted. Groundwater may be pumped out using pumps or other processes to at least 2 feet below and compaction activities. Well point systems may be used if deeper excavations are required for proper and safe construction.

A specialty contractor should design these systems and adhere to any regulatory standards.

5.3 Compaction Recommendations

Once initial site clearing has been performed, the exposed in-situ soils in the building(s) footprint should be properly compacted until the surface is firm and unyielding. The compaction should extend 5 feet beyond the perimeter of the building(s). Care should be taken when compacting adjacent to existing structures. A self-propelled vibratory roller should be used to compact the exposed in-situ soils. The proof rolling should be observed by PACIFICA to identify and mitigate any weak subgrade conditions.

If any locations of in-situ soils overly deflect under the weight of the roller, then the soils should be removed to a depth of 24 inches and replaced with properly compacted structural fill materials.

The structural fill soils should be compacted to 98% of the Modified Proctor maximum dry density per ASTM D1557. Wetting of the subgrade soils may be used in order to achieve proper compaction.

5.4 Structural Fill Soils

Structural fill soils should be inorganic and consist of granular material containing less than 12 percent passing the U.S. Standard No. 200 mesh sieve, a maximum particle size of 3 inches and have a Unified Soil Classification System (USCS) designation of GP, GW, GP-GM, GW-GM, SP, SW, SP-SM, or SW-SM. The structural fill material may be composed of either clean sands and/or limerock. The use of “Cyclone Sand” is not permitted.

Density tests should be performed by a qualified technician working under the supervision of the geotechnical engineer and be in accordance with the appropriate ASTM standards. The representative of the geotechnical engineer should be present and agree with the placement and compaction of all structural fill materials.

Loose lifts not exceeding 12 inches should be performed on all structural fill materials. The lifts should be compacted to 98% of the Modified Proctor (ASTM D1557). If a small vibratory plate or roller is used, then loose lifts should not exceed 8 inches.

PACIFICA Project No.: 320-25483 Page 5

5.5 Shallow Foundation Construction

Based on the results of the geotechnical exploration, the following recommendations apply to the soils beneath the building(s) foundations. In-situ or imported structural fill soils at the base of the footing excavations should be compacted to at least 98% of the Modified Proctor (ASTM D1557).

If any locations of in-situ or imported structural fill soils overly deflect under the weight of the compactor/roller, then the soils should be removed to a depth of 24 inches and replaced with properly compacted structural fill materials.

6.0 REPORT LIMITATIONS

These geotechnical engineering services have been performed, findings obtained, and recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices at the time of this report. PACIFICA is not responsible for the conclusions, opinions, or recommendations made by others based on this data. No other warranties are implied or expressed.

After the plans and specifications are complete, PACIFICA should be provided the opportunity to review the final design and specifications, in order to verify that the earthwork and foundation recommendations are properly interpreted and implemented. At that time, it may be necessary to submit supplemental recommendations. If PACIFICA is not afforded the opportunity to participate in construction-related aspects of foundation installation as recommended in this report, we can accept no responsibility for the interpretation of our recommendations made in this report or for foundation performance.

The scope of the investigation was intended to evaluate soil conditions within the influence of the proposed foundations. The analyses and recommendations submitted in this report are based upon the data obtained from the soil borings performed at the locations indicated. If any subsoil variations become evident during the course of this project, a re-evaluation of the recommendations contained in this report will be necessary after we have had an opportunity to observe the characteristics of the conditions encountered. The applicability of the report should also be reviewed in the event significant changes occur in the design, nature, or location of the proposed structures. The scope of our services did not include an environmental assessment for the presence or absence of hazardous or toxic materials in the soil and groundwater. Any statements in this report regarding odors, staining of soils, or other unusual conditions observed are strictly for the information of our client.

This report has been prepared for the exclusive use of HSQ Group, Inc. and their design consultants for the construction of the proposed Seminole Canopy 2 at the Big Cypress Reserve Re-Pump Station.

Soil Map—Hendry County, Florida

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

2/10/2025

496467 496476 496485 496494 496503 496512

496467 496476 496485 496494 496503 496512

26° 19' 59'' N

' 7 '' W

26° 19' 59'' N

' 5 '' W

26° 19' 56'' N

' 7 '' W

26° 19' 56'' N

' 5 '' W

N

Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 17N WGS84 0 15 30 60 90

Feet 0 5 10 20 30

Meters Map Scale: 1:349 if printed on A portrait (8.5" x 11") sheet.

Soil Map may not be valid at this scale.

MAP LEGEND MAP INFORMATION

Area of Interest (AOI) Area of Interest (AOI)

Soils Soil Map Unit Polygons

Soil Map Unit Lines

Soil Map Unit Points

Special Point Features Blowout

Borrow Pit

Clay Spot

Closed Depression

Gravel Pit

Gravelly Spot

Landfill

Lava Flow

Marsh or swamp

Mine or Quarry

Miscellaneous Water

Perennial Water

Rock Outcrop

Saline Spot

Sandy Spot

Severely Eroded Spot

Sinkhole

Slide or Slip

Sodic Spot

Spoil Area

Stony Spot

Very Stony Spot

Wet Spot

Other

Special Line Features

Water Features Streams and Canals

Transportation Rails

Interstate Highways

US Routes

Major Roads

Local Roads

Background Aerial Photography

The soil surveys that comprise your AOI were mapped at 1:24,000.

Warning: Soil Map may not be valid at this scale.

Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale.

Please rely on the bar scale on each map sheet for map measurements.

Source of Map: Natural Resources Conservation Service Web Soil Survey URL:

Coordinate System: Web Mercator (EPSG:3857)

Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required.

This product is generated from the USDA-NRCS certified data as of the version date(s) listed below.

Soil Survey Area: Hendry County, Florida Survey Area Data: Version 24, Aug 26, 2024

Soil map units are labeled (as space allows) for map scales 1:50,000 or larger.

Date(s) aerial images were photographed: Nov 14, 2021—Nov 23, 2021

The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident.

Soil Map—Hendry County, Florida

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

2/10/2025

Map Unit Legend

Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI

1 Cypress Lake sand, 0 to 2 percent slopes

0.5 100.0%

Totals for Area of Interest 0.5 100.0%

Soil Map—Hendry County, Florida

Natural Resources Conservation Service

Web Soil Survey National Cooperative Soil Survey

2/10/2025

3/4" 3/8" #4 #10 #16 #40 #50 #100 #200 Liquid

Limit

Plastic

Limit

Plasticity

Index

B-1 18-20 SM 91.0 84.0 77.0 67.0 61.0 49.0 39.0 25.0 18.4 2.9 21

B-1 4-6 SP 100.0 99.0 93.0 87.0 85.0 59.0 28.0 4.0 1.0 - 18

Atterberg Limits Organic

Content

Natural

Moisture

Content (%)

Summary of Laboratory Test Results

Seminole Tribe of Florida Canopy #2

PACIFICA Project No.: 320-25483

Boring

Number

Sample

Depth (ft)

USCS

Classification

Sieve Analysis, Percentage Passing