07c9664b9f52054027fdad49456b2c4ebc86240182b7084a48a1826485a4.pdf

W Sunset Blvd - New Lift Station Geotechnical Report

Fort Walton Beach, Okaloosa County, Florida

Ardurra Group

SESI Project No: P26-057

February 9, 2026 Southern Earth Sciences, Inc. 7500 McElvey Rd, Panama City Beach, Florida 32408 - (850) 769-4773

MOBILE · MONTGOMERY · SUMMERDALE · DESTIN · PANAMA CITY · PENSACOLA · TALLAHASSEE · BATON ROUGE · MANDEVILLE · NEW ORLEANS · LONG BEACH

PANAMA CITY OFFICE

7500 McElvey Road, Ste. A

Panama City Beach, FL 32408

Tel: (850) 769-4773 Fax: (850) 872-9967 www.soearth.com

Ardurra Group , Inc. February 9, 2026 1988 Lewis Turner Blvd, Unit 3 File No: P26-057 Fort Walton Beach, FL 32547 Attn: Ms. Kathryn Stephens, P.E.

Subject: Geotechnical Services for the New Lift Station on W Sunset Blvd in Fort Walton

Beach, Florida

Dear Ms. Stephens:

Southern Earth Sciences, Inc., has completed the geotechnical services for the Proposed Lift Station on W Sunset Blvd in Fort Walton Beach, Florida. Our services were performed in general accordance with proposal number XP26-1.19.26-4, dated January 19, 2026. This report presents the results of our field and laboratory testing and includes the soil parameters for the design of the lift station.

FIELD INVESTIGATIVE PROCEDURE:

Prior to our field testing, the boring location was marked and Sunshine State One Call of Florida was contacted to locate underground utilities. On January 29, 2026, personnel with our firm traveled to the project site and completed the field testing for the above referenced project. For our geotechnical investigation, we performed one (1) cone sounding to a depth of approximately 27 feet below the existing ground surface. The cone penetrometer is track mounted and rather than sampling and testing at five foot intervals, as normally done with standard penetration borings, the cone penetrometer is an electronic device that provides continuous evaluation of the soils bearing capacity through point and frictional resistances. The cone penetrometer is hydraulically pushed into the soil with point and frictional resistances obtained continuously on a computer printout. This testing equipment provides an accurate definition of the soil strength characteristics and the changes in stratification. Cone soundings were performed in general accordance with ASTM D5778.

A direct push boring was performed at the cone sounding location to approximately 20 feet below the existing ground surface. The direct push samples were obtained with our Geoprobe 6622 and the DT22 soil sampling system. This is a closed-piston sampler, with an inner piston rod and outer drive casing, and is driven to the top of the sampling interval. The inner piston rod is removed, and the sampler is driven to collect a soil sample. The soil samples are collected in a clear 5-foot PVC liner and were delivered back to our laboratory for soil classification.

Ardurra Group, Inc.

W Sunset Blvd – New Lift Station

Fort Walton Beach

Test locations were established in the field by using a handheld GPS and estimating right angles with reference to existing landmarks; therefore, our test locations should be considered approximate. See the attached Figure for our approximate test locations.

LABORATORY TESTING PROCEDURES:

Laboratory investigative work consisted of physical examination of samples obtained during the soil test boring operation. Soil samples were visually classified in the laboratory in accordance with the Unified Soil Classification System. Evaluation of these samples, in conjunction with cone penetration resistances, have been used to estimate soil characteristics.

Natural Moisture: Two (2) samples were selected for determination of their natural moisture content. In the laboratory, each sample was weighed, dried, and its moisture content was calculated in general accordance with ASTM D2216.

Percent Passing 200 Mesh Sieve: Two (2) samples were selected to determine their percent of materials, by dry weight, finer than the U.S. Number 200 Mesh Sieve. This test was performed in general accordance with ASTM D1140.

The laboratory test results are shown on the boring logs at the depth of the tested sample. Abbreviations of laboratory data are shown below:

NM = Natural Moisture Content (%) -200 = Percent Finer than the U.S. No. 200 Mesh Sieve

SITE & SOIL CONDITIONS:

The proposed lift station will be located on the west side of W Sunset Blvd approximately 1050lf south of the intersection of Pelham Road. The lift station will be near the address of 630 W Sunset Blvd. The proposed lift station area is cleared with few trees and surface grasses. Based upon Okaloosa County GIS and Google Earth, existing elevation is approximately +9 to +10 Ft. The logs of our cone sounding and direct push boring are attached.

The elevation of our test location is unknown; however, should be in the range of +9 Ft.

The soils encountered within the depths of our cone sounding and boring are sands. The sands vary in color and texture ranging from slightly silty to clean sands. The sands within the top foot contain various amounts of organics. Beyond the top foot, loose slightly silty sands are encountered to depths of approximately seven feet below the existing ground surface. For the remainder of our cone sounding the sands increase in density with depth; however, at approximately 18 to 23 feet the sands gradually decrease from dense to medium dense.

On the date of our field testing (January 29, 2026), the groundwater level was measured at 6.4 feet below existing ground surface. Fluctuations in the water table will occur due to seasonal precipitation/evapotranspiration differences, neighboring pond/drainage influences, and tidal influences; therefore, groundwater levels should be confirmed prior to foundation construction.

SOIL PARAMETERS FOR LIFT STATION DESIGN:

In evaluating the cone soundings, we have used correlations that were previously made between cone penetration resistances and foundation stabilities observed in soil conditions similar to those encountered at your site. Based upon the results of our field and laboratory testing, we have estimated the soil parameters for the design of the lift station. The soil parameters are summarized in the following tables:

Table I: Boring Location C-1

Depth: Soil Classification Friction Angle (degrees)

Cohesion (psf.)

Unit Weight (pcf.)

0 – 3 ft. SP-SM, SP 29 0 95 3 – 7 ft. SP-SM 28 0 45

7 – 11 ft. SP-SM, SP 32 0 50 11 – 18 ft. SP 34 0 54 18 – 22 ft. SP, SP-SM 31 0 51 22 – 27 ft. SP 36 0 57

Currently, the dimensions of the lift station are in development; however, we anticipate the diameter to be in the range of 8 to 10-ft with an embedment depth of approximately 15 feet. It is our understanding that the top of the lift station will be near existing grade. As mentioned above, groundwater was encountered at a depth of approximately 6.4 feet on the date of our field testing; therefore, the bottom of the lift station will be below the groundwater level. We anticipate the weight of the removed overburden soils to be greater than the added loads and settlements will be minimal. The soils at the bottom of the foundation will be medium dense sands. However, at the bottom of the lift station we recommend a minimum of 12-inches of compacted crushed stone. Backfill soils placed around the lift station should be placed in one-foot lifts and compacted each lift until a density of 95% of the modified proctor maximum dry density is achieved. Only hand-operated equipment should be used around the lift station. We anticipate that the existing soils can be used for backfill, however, any soils containing organics should not be reused. Excavated soils below the water table will be saturated and should be given time to drain prior to placement. Placement of overly saturated soils will delay the construction sequence.

Dewatering will be required for construction of the lift station. A well point system would be the most appropriate with the soil conditions found at this location. If open cut will be used for construction, a sheet pile cofferdam will likely be required.

CONSTRUCTION TESTING SERVICES:

The effectiveness of the pavement will depend significantly on the proper preparation of the soils, as indicated previously. Therefore, we recommend the owner employ Southern Earth Sciences, Inc., as the testing laboratory to perform construction testing services. If we are not employed to provide construction testing services, Southern Earth Sciences, Inc., can not accept any responsibility for any conditions, which deviate from those described in this geotechnical report. Southern Earth Sciences, Inc., should be invited to the pre-construction conference to discuss the project with all interested parties so that the project may be completed expeditiously and to the intent of our geotechnical report. We would be pleased to review the plans and specifications as they relate to the soil preparation and provide a fee proposal for construction testing.

GENERAL COMMENTS:

Professional judgments on design criteria are presented in this letter. These are based partly on our evaluations of technical information provided, partly on our understanding of the characteristics of the project being planned, and partly on our general experience with subsurface conditions in the area. We do not guarantee performance of the project in any respect, only that our judgments meet the standard of care of our profession.

This information is exclusively for the use and benefit of the addressee(s) identified on the first page of this report and is not for the use or benefit of, nor may it be relied upon by any other person or entity. The contents of this letter may not be quoted in whole or in part or distributed to any person or entity other than the addressee(s) hereof without, in each case, the advance written consent of the undersigned.

This report has been prepared in order to aid in the evaluation of this property and to assist the engineers in the design of the proposed lift station. It is intended for use with regard to the specific project discussed herein, and any substantial changes in the loads, locations, or reported grades shall be brought to our attention immediately so that we may determine how such changes may effect our conclusions and recommendations. We would appreciate the opportunity to review the plans and specifications for the foundation and floor construction to verify that our conclusions and recommendations are interpreted correctly. Our report does not address environmental issues which may be associated with the subject property.

While the soundings and borings performed for this project are representative of subsurface soil conditions at their respective locations and for their respective vertical reaches, local variations of the subsurface materials are anticipated and may be encountered. The boring logs and related information are based on the driller’s logs and visual examination of selected samples in the laboratory. Delineation between soil types shown on the boring logs is approximate, and soil descriptions represent our interpretation of subsurface conditions at the designated boring location on the particular date drilled.

We appreciate the opportunity to be of service to you on this project. Should additional information be required please advise.

Yours Very Truly, SOUTHERN EARTH SCIENCES, INC.

Howell Logan, E.I.

Project Engineer

Logan A. Fowler, P.E.

Eng. Reg. No. 82343 State of Florida

This item has been digitally signed and sealed by Logan A. Fowler, P.E.

(FL Eng. License No.: 82343) using a Digital Signature. Printed copies of this document are not considered signed and sealed and the authentication code must be verified on any electronic copies.

C-1

DRAWN BY:

CHECKED BY:

DATE:

SCALE:

HLSESI FILE NO:

P26-057

New Lift Station on W Sunset Blvd.

Fort Walton Beach, FL

2/5/26

1:100

FIGURE I

APPROXIMATE TEST

LOCATIONS

LF

00 100 200

Southern Earth Sciences, Inc.

Operator: Pat Conroy

Sounding: C-1

Cone Used: DDG1702

CPT Date/Time: 1/29/2026 9:57:12 AM

Location: New Lift Station on W Sunset Blvd.

Job Number: P26-057

Maximum Depth = 27.23 feet Depth Increment = 0.164 feet

*Soil behavior type and SPT based on data from UBC-1983

Tip Resistance

Qt TSF

Depth (ft)

Local Friction

Fs TSF

Pore Pressure

Pw PSI

Friction Ratio

Fs/Qt (%)

Soil Behavior Type*

Zone: UBC-1983

1 sensitive fine grained 2 organic material 3 clay

4 silty clay to clay 5 clayey silt to silty clay 6 sandy silt to clayey silt

7 silty sand to sandy silt 8 sand to silty sand 9 sand

10 gravelly sand to sand 11 very stiff fine grained (*) 12 sand to clayey sand (*)

SPT N*

60% Hammer

Groundwater: 6.4 feet Elevation: Unknown

SP-

SM

SP

SP-

SM

SP-

SM

SP

SP

Dark Grey Slightly Silty Fine SAND with Organics Brown and Red Slightly Clayey Fine SAND with Trace Organics Brown and Orange Slightly Silty Fine

SAND

Tan and Light Brown Slightly Silty Medium to Fine SAND

Tan and Light Grey Medium to Fine

SAND

Light Tan and Light Gray Fine SAND

LL

N Value (blows/ft)

20 40 60 80

Page 1 of 1LOG OF BORING C-1 New Lift Station on W Sunset Blvd.

Fort Walton Beach, FL

P26-057

01/29/26

SPT Shelby Tube

Notes:

PROJECT:

LOCATION:

PROJECT NO.:

DATE:

METHOD:

DRILLER:

ENGR / GEOL:

SURFACE ELEVATION:

Direct Push

PC

LF

Unknown

Per Plan

Water Level

N A

T U

R A

L M

O

IS

T U

R E

P A

S S

IN

G

S

IE

V

E

)Soil Symbols Sampler Symbols and Field Test Data

Water Observations: Groundwater Measured at 6.4 Feet Below Existing Ground Surface

Elevation / Depth

PL PI

ATTERBERG

LIMITS (%)

LI

Q

U

ID

L

IM

IT

P

LA

S T

IC

L

IM

IT

P

LA

S T

IC

IT

Y

IN

D E

X

MATERIAL DESCRIPTION

LOCATION

USCS

N - SPT Data (Blows/Ft) P - Pocket Penetrometer (tsf)

Sample Key:

PL LLMC

20 40 60 80 Atterberg Limits Natural Moisture

Measured: Perched:Est. Seasonal High GWL:

LO

G

O F

B O

R

IN

G

P

-0

.G P

J S

E S

P C

F L.

G D

T

2/ 6/

Geotechnical Services Are Performed for Specific Purposes, Persons, and Projects Geotechnical engineers structure their services to meet the specific needs of their clients. A geotechnical engineering study conducted for a civil engi-neer may not fulfill the needs of a construction contractor or even another civil engineer. Because each geotechnical engineering study is unique, each geotechnical engineering report is unique, prepared solely for the client. No one except you should rely on your geotechnical engineering report without first conferring with the geotechnical engineer who prepared it. And no one

— not even you — should apply the report for any purpose or project except the one originally contemplated.

Read the Full Report Serious problems have occurred because those relying on a geotechnical engineering report did not read it all. Do not rely on an executive summary.

Do not read selected elements only.

A Geotechnical Engineering Report Is Based on A Unique Set of Project-Specific Factors Geotechnical engineers consider a number of unique, project-specific fac-tors when establishing the scope of a study. Typical factors include: the client's goals, objectives, and risk management preferences; the general nature of the structure involved, its size, and configuration; the location of the structure on the site; and other planned or existing site improvements, such as access roads, parking lots, and underground utilities. Unless the geotechnical engineer who conducted the study specifically indicates oth-erwise, do not rely on a geotechnical engineering report that was:

• not prepared for you,

• not prepared for your project,

• not prepared for the specific site explored, or

• completed before important project changes were made.

Typical changes that can erode the reliability of an existing geotechnical engineering report include those that affect:

• the function of the proposed structure, as when it's changed from a parking garage to an office building, or from a light industrial plant to a refrigerated warehouse,

• elevation, configuration, location, orientation, or weight of the proposed structure,

• composition of the design team, or

• project ownership.

As a general rule, always inform your geotechnical engineer of project changes—even minor ones—and request an assessment of their impact.

Geotechnical engineers cannot accept responsibility or liability for problems that occur because their reports do not consider developments of which they were not informed.

Subsurface Conditions Can Change A geotechnical engineering report is based on conditions that existed at the time the study was performed. Do not rely on a geotechnical engineer-ing report whose adequacy may have been affected by: the passage of time; by man-made events, such as construction on or adjacent to the site;

or by natural events, such as floods, earthquakes, or groundwater fluctua-tions. Always contact the geotechnical engineer before applying the report to determine if it is still reliable. A minor amount of additional testing or analysis could prevent major problems.

Most Geotechnical Findings Are Professional Opinions Site exploration identifies subsurface conditions only at those points where subsurface tests are conducted or samples are taken. Geotechnical engi-neers review field and laboratory data and then apply their professional judgment to render an opinion about subsurface conditions throughout the site. Actual subsurface conditions may differ—sometimes significantly— from those indicated in your report. Retaining the geotechnical engineer who developed your report to provide construction observation is the most effective method of managing the risks associated with unanticipated conditions.

A Report's Recommendations Are Not Final Do not overrely on the construction recommendations included in your report. Those recommendations are not final, because geotechnical engi-neers develop them principally from judgment and opinion. Geotechnical engineers can finalize their recommendations only by observing actual

Important Information About Your

Subsurface problems are a principal cause of construction delays, cost overruns, claims, and disputes.

Geotechnical Engineering Report The following information is provided to help you manage your risks.

subsurface conditions revealed during construction. The geotechnical engineer who developed your report cannot assume responsibility or liability for the report's recommendations if that engineer does not perform construction observation.

A Geotechnical Engineering Report Is Subject to Misinterpretation Other design team members' misinterpretation of geotechnical engineering reports has resulted in costly problems. Lower that risk by having your geo-technical engineer confer with appropriate members of the design team after submitting the report. Also retain your geotechnical engineer to review perti-nent elements of the design team's plans and specifications. Contractors can also misinterpret a geotechnical engineering report. Reduce that risk by having your geotechnical engineer participate in prebid and preconstruction conferences, and by providing construction observation.

Do Not Redraw the Engineer's Logs Geotechnical engineers prepare final boring and testing logs based upon their interpretation of field logs and laboratory data. To prevent errors or omissions, the logs included in a geotechnical engineering report should never be redrawn for inclusion in architectural or other design drawings.

Only photographic or electronic reproduction is acceptable, but recognize that separating logs from the report can elevate risk.

Give Contractors a Complete Report and Guidance Some owners and design professionals mistakenly believe they can make contractors liable for unanticipated subsurface conditions by limiting what they provide for bid preparation. To help prevent costly problems, give con-tractors the complete geotechnical engineering report, but preface it with a clearly written letter of transmittal. In that letter, advise contractors that the report was not prepared for purposes of bid development and that the report's accuracy is limited; encourage them to confer with the geotechnical engineer who prepared the report (a modest fee may be required) and/or to conduct additional study to obtain the specific types of information they need or prefer. A prebid conference can also be valuable. Be sure contrac-tors have sufficient time to perform additional study. Only then might you be in a position to give contractors the best information available to you, while requiring them to at least share some of the financial responsibilities stemming from unanticipated conditions.

Read Responsibility Provisions Closely Some clients, design professionals, and contractors do not recognize that geotechnical engineering is far less exact than other engineering disci-plines. This lack of understanding has created unrealistic expectations that have led to disappointments, claims, and disputes. To help reduce the risk of such outcomes, geotechnical engineers commonly include a variety of explanatory provisions in their reports. Sometimes labeled "limitations" many of these provisions indicate where geotechnical engineers’ responsi-bilities begin and end, to help others recognize their own responsibilities and risks. Read these provisions closely. Ask questions. Your geotechnical engineer should respond fully and frankly.

Geoenvironmental Concerns Are Not Covered The equipment, techniques, and personnel used to perform a geoenviron-mental study differ significantly from those used to perform a geotechnical study. For that reason, a geotechnical engineering report does not usually relate any geoenvironmental findings, conclusions, or recommendations;

e.g., about the likelihood of encountering underground storage tanks or regulated contaminants. Unanticipated environmental problems have led to numerous project failures. If you have not yet obtained your own geoen-vironmental information, ask your geotechnical consultant for risk man-agement guidance. Do not rely on an environmental report prepared for someone else.

Obtain Professional Assistance To Deal with Mold Diverse strategies can be applied during building design, construction, operation, and maintenance to prevent significant amounts of mold from growing on indoor surfaces. To be effective, all such strategies should be devised for the express purpose of mold prevention, integrated into a com-prehensive plan, and executed with diligent oversight by a professional mold prevention consultant. Because just a small amount of water or moisture can lead to the development of severe mold infestations, a num-ber of mold prevention strategies focus on keeping building surfaces dry.

While groundwater, water infiltration, and similar issues may have been addressed as part of the geotechnical engineering study whose findings are conveyed in this report, the geotechnical engineer in charge of this project is not a mold prevention consultant; none of the services per-formed in connection with the geotechnical engineer’s study were designed or conducted for the purpose of mold preven-tion. Proper implementation of the recommendations conveyed in this report will not of itself be sufficient to prevent mold from growing in or on the structure involved.

Rely, on Your ASFE-Member Geotechncial Engineer for Additional Assistance Membership in ASFE/The Best People on Earth exposes geotechnical engineers to a wide array of risk management techniques that can be of genuine benefit for everyone involved with a construction project. Confer with you ASFE-member geotechnical engineer for more information.

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Copyright 2004 by ASFE, Inc. Duplication, reproduction, or copying of this document, in whole or in part, by any means whatsoever, is strictly prohibited, except with ASFE’s specific written permission. Excerpting, quoting, or otherwise extracting wording from this document is permitted only with the express written permission of ASFE, and only for purposes of scholarly research or book review. Only members of ASFE may use this document as a complement to or as an element of a geotechnical engineering report. Any other firm, individual, or other entity that so uses this document without being an ASFE member could be commiting negligent or intentional (fraudulent) misrepresentation.

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