Attch 8 EHRM GeoTech Boring Report.pdf

Geotechnical Subsurface Investigation

Proposed EHRM

Upgrades

West Palm Beach VAMC , Florida

Specialized Engineering

Solutions

Omaha, Nebraska

August 15, 2022

TTL Project No. 2073502

1915 North 12th Street Toledo, OH 43604-5305 419-342-2222

TTL Associates, Inc.

www.ttlassoc.com

1915 North 12th Street

Toledo, OH 43604-5305

T 419-324-2222

F 419-241-1808 www.ttlassoc.com

Teamwork - Trust - Leadership Since 1927

August 15, 2022 TTL Project No.2073502

Mr. Tony Pabon, PMP Specialized Engineering Solutions 10360 Ellison Circle Omaha, Nebraska 68134

Geotechnical Subsurface Investigation Proposed EHRM Upgrades

West Palm Beach Veteran Affairs Medical Center West Palm Beach, Florida

Dear Mr. Pabon:

Following is the report of the geotechnical subsurface investigation performed by TTL Associates, Inc. (TTL) for the referenced project. This study was performed in accordance with TTL Proposal No. 2073502, dated January 7, 2022, and authorized by you on July 10, 2022.

This report contains the results of the subsurface investigation, an engineering interpretation of these results with respect to the project characteristics, and our recommendations for design and construction of building foundations and floor slabs for the proposed development.

Soil and rock samples collected during this investigation will be stored at our laboratory for 90 days from the date of this report. The samples will be discarded after this time unless you request that they be saved or delivered to you.

Should you have any questions regarding this report or require additional information, please contact our office.

Sincerely, TTL Associates, Inc.

Imad El Hajjar, EI Curtis E. Roupe, P.E.

Geotechnical Project Manager Vice President

T:\Projects\2073502 - …\Reports and Other Deliverables\2073502 TTL Geotech Report - VAMC Proposed EHRM Upgrades - West Palm Beach, Florida.docx

GEOTECHNICAL SUBSURFACE INVESTIGATION

PROPOSED EHRM UPGRADES

WEST PALM BEACH VETERAN AFFAIRS MEDICAL CENTER

WEST PALM BEACH, FLORIDA

FOR

SPECIALIZED ENGINEERING SOLUTIONS

10360 ELLISON CIRCLE

OMAHA, NEBRASKA 68134

SUBMITTED

AUGUST 15, 2022

TTL PROJECT NO. 2073502

TTL ASSOCIATES, INC.

1915 NORTH 12TH STREET

TOLEDO, OHIO 43604

(419) 324-2222

(419) 321-6257 FAX

Specialized Engineering Solutions August 2022 TTL Project No. 2073502 Page i

TABLE OF CONTENTS

Page No.

TABLE OF CONTENTS ...................................................................................................... i

1.0 INTRODUCTION

2.0 INVESTIGATIVE PROCEDURES

3.0 PROPOSED CONSTRUCTION

4.0 GENERAL SITE AND SUBSURFACE CONDITIONS

4.1 General Site Conditions

4.3 General Soil Conditions

4.3 Groundwater Conditions

5.0 DESIGN RECOMMENDATIONS

5.1 Shallow Building Foundations

5.3 Subgrades

5.3.1 Existing Subgrade

5.3.2 Modified Subgrade

5.4 Floor Slabs

5.8 Groundwater Control

5.9 Excavations and Slopes

6.0 CONSTRUCTION RECOMMENDATIONS

6.1 Site and Subgrade Preparation

6.2 Fill

6.3 Foundation Excavations

7.0 QUALIFICATION OF RECOMMENDATIONS

PLATES

Plate 1.0 Site Location Map Plate 2.0 Test Boring Location Plan

Appendices A Logs of Test Borings B-1 and B-2 B Legend Key C Tabulation of Test Data D Laboratory Test Results

TTL Project No. 2073502 Page 1

1.0 INTRODUCTION

This geotechnical subsurface investigation report has been prepared for the proposed new server room structure at the West Palm Beach Veteran Affairs Medical Center located at 7305 N Military Trail, West Palm Beach, Florida 33410. The general area of the project is shown on the attached Site Location Map (Plate 1.0).

This report summarizes our understanding of the proposed construction, describes the investigative and testing procedures, presents the findings, discusses our evaluations and conclusions, and provides our design and construction recommendations for foundations and floor slabs.

This study was performed in accordance with TTL Proposal No. 2073502, dated January 7, 2022, and authorized by Mr. Tony Pabon of SES on July 10, 2022.

The purpose of this investigation was to evaluate the subsurface conditions and laboratory data relative to the design and construction of foundations and building slabs at the referenced site.

This investigation included two (2) test borings, field and laboratory soil testing, and a geotechnical engineering evaluation of the test results.

This report includes:

• A description of the subsurface soil and groundwater conditions encountered in the borings.

• Design recommendations for building foundations and floor slabs related to the proposed development.

• Recommendations concerning soil- and groundwater-related construction procedures such as site preparation, earthwork, foundation and pavement construction, and related field testing.

The scope of this study did not include an environmental assessment of the subsurface materials.

TTL Project No. 2073502 Page 2

2.0 INVESTIGATIVE PROCEDURES

This subsurface investigation included two (2) test borings drilled on July 15, 2022. The subsurface investigation was completed by Terracon of Fort Lauderdale, Florida, under the direction of an on-site TTL geotechnical professional. The borings were located in the field by TTL based on a boring location plan that was provided before mobilizing to the site. The approximate locations of the test borings are shown on the attached Test Boring Location Plan (Plates 2.0).

Prior to starting the drilling operations, the borings were cleared by a private utility locating contractor. The test borings were performed in general accordance with geotechnical investigative procedures outlined in ASTM Standard D 1452 and were advanced using mud rotary drilling technique utilizing a 3¼-inch outside diameter hollow-stem augers along with a 2-7/8 -inch diameter tricone roller bit to 50 feet below exigent grades. During auger advancement, soil samples were generally collected continuously to a depth of 10 feet, and at 5-foot intervals thereafter using a split-spoon sampler. The soil samples were sealed in jars and transported to our laboratory for further classification and testing.

Split-spoon (SS) samples were obtained by the Standard Penetration Test (SPT) Method (ASTM D 1586), which consists of driving a 2-inch outside diameter split-barrel sampler into the soil with a 140-pound weight falling freely through a distance of 30 inches. The sampler was driven in three or four successive 6-inch increments with the number of blows per increment being recorded. The sum of the number of blows required to advance the sampler the second and third 6-inch increments is termed the Standard Penetration Resistance (N-value) and is presented on the Logs of Test Borings attached to this report. The samples were sealed in jars and transported to our laboratory for further classification and testing.

All of the recovered samples of the subsoils were visually or manually classified in accordance with the Unified Soil Classification System (USCS) (ASTM D 2487 and D 2488) and tested in our laboratory for moisture content (ASTM D 2216). Atterberg limits tests (ASTM D 4318) and particle size analyses (ASTM D 422) were performed on two selected samples. The results of these tests are presented on the Logs of Test Borings, and Tabulation of Test Data sheets attached to this report.

A composite soil sample from the upper 4 feet of subgrade was selected for soil resistivity testing (ASTM G 57). A resistivity value of 3250 ohms-cm at 38.6% MC was determined.

TTL Project No. 2073502 Page 3

Experience indicates that the actual subsoil conditions at a site could vary from those generalized on the basis of test borings made at specific locations, especially at previously developed site such as this site. Therefore, it is essential that a geotechnical engineer be retained to provide soil engineering services during the site preparation, excavation, and foundation phases of the proposed project. This is to observe compliance with the design concepts, specifications, and recommendations, and to allow design changes in the event

TTL Project No. 2073502 Page 4

3.0 PROPOSED CONSTRUCTION

It is our understanding that the project consists of building a new server room structure at the West Palm Beach Veteran Affairs Medical Center located at 7305 N Military Tr, West Palm Beach, FL 33410. The addition is proposed within a grassy or pavement area located southeast of the exiting Mental Health Domiciliary at the location of an exiting workout area. The proposed new structure is expected to consist of a single story structure with a slab on grade and supported on shallow foundations.

Based on the provided information, maximum column loads are expected to be 100 kips and maximum wall loads are expected to be 1,500 pounds per lineal foot (plf).

We have assumed that final grades will approximate existing grades present at the time of this investigation.

TTL Project No. 2073502 Page 5

4.0 GENERAL SITE AND SUBSURFACE CONDITIONS

4.1 General Site Conditions

At the time of this investigation, the area of proposed development surrounding the existing workout area, consisted predominantly of permeable concrete pavement and a grassy area. The site is flat with ground surface elevations at the boring locations on the order of Elevs. 14 feet.

The surface materials encountered in Boring B-1 consisted of an approximately 3-inch-thick layer of topsoil. Boring B-2 was performed within the permeable pavement area and encountered surface materials consisted of an approximately 3½ inch thick layer of concrete underlain by a 3 inch thick layer of crushed stone aggregates (i.e., Aggregate Base).

4.3 General Soil Conditions

Based on the results of the field and laboratory tests, the subsurface conditions were found to have a stratigraphy consisting of granular soils to borings termination at a depth of 50 feet below existing grades (Elev. -36±). The granular soils can be generally described as five strata with varying strength and moisture characteristics.

The encountered soil strata are described below and additional descriptions of the stratigraphy encountered in the borings are presented on the Logs of Test Borings.

Stratum I consisted of predominantly very loose to loose native granular soils encountered in in Boring B-1 underlying the surface materials to approximately 4 feet below existing grade (Elev. 10±). These granular soils consisted of silty sand (SM) mixed with trace amounts of gravel and organics. SPT N-values of 3 and 10 blows per foot (bpf) and moisture contents of 17 and 20 percent were noted within this stratum.

Atterberg limit testing for a sample obtained from Borings B-1 (SS-1) revealed that the Stratum I soils were non plastic. These values, along with gradation results, are indicative of silty sand (SM) in accordance with USCS designations

Stratum II consisted of predominantly medium dense native granular soils encountered in Boring B-1, underlying Stratum I and underlying the surface materials in Boring B-2 to depths ranging from approximately 4 to 6 feet (Elev. 10± to Elev. 8±). These granular soils consisted of poorly graded sand (SP) mixed with trace amounts of silt. SPT N-values ranged from 12 to 16 bpf. Moisture contents ranged from 14 to 20 percent.

TTL Project No. 2073502 Page 6

Atterberg limit testing for a sample obtained from Borings B-2 (SS-4) revealed that the Stratum II soils were non plastic .These values, along with gradation results, are indicative of poorly graded sand (SP) in accordance with USCS designations

Stratum III consisted of predominantly very loose to loose native granular soils encountered underlying Stratum II to depths ranging from approximately 23½ to 28½ feet (Elev. -9± to Elev. -14±). These granular soils consisted of poorly graded sand (SP), mixed with varying amounts of silt and gravel. SPT N-values ranged from 1 to 8 bpf. It is our experience that low SPT N-values determined for granular soils encountered at or slightly below the groundwater table are not necessarily indicative of the actual compactness of the soils, but may reflect a bias toward apparent looser compaction due to sampling disturbance phenomena coincident with soil saturation due to groundwater. Moisture contents ranged from 15 to 30 percent.

Stratum IV consisted of predominantly medium dense native granular soils encountered underlying Stratum III to depths ranging from approximately 38½ to 43½ feet (Elev. -24± to Elev. -29±). These granular soils consisted of poorly graded sand (SP) mixed with varying amounts of silt. SPT N-values ranged from 11 to 19 bpf. Moisture contents ranged from 19 to 27 percent.

Stratum IV consisted of predominantly dense to very native granular soils encountered underlying Stratum IV to the planned boring terminated depths at approximately 50 feet (Elev.

-36±). These granular soils consisted of poorly graded sand (SP) mixed with trace amounts of silt. SPT N-values ranged from 34 to 61 bpf. Moisture contents ranged from 23 to 26 percent.

Additional descriptions of the stratigraphy encountered in the borings are presented on the logs attached to this report.

4.3 Groundwater Conditions

Groundwater was initially encountered during drilling in both Borings B-1 and B-2 at depths of 6 and 4 feet below existing grades, respectively (Elev. 10± and 8±). Water was introduced into the borehole upon starting the mud rotary drilling operations. Therefore, a groundwater level observation could not be made upon completion of drilling operations. Due to the granular soils which were encountered in the test borings, the groundwater observations likely reflect the approximate depth of ambient water conditions at the time of our investigation.

Instrumentation was not installed to observe long-term groundwater levels.

However, this investigation did not include research of possible hydrological influences at the project site. It should be noted that groundwater elevations can fluctuate with seasonal and climatic influences. Specifically, groundwater level may approach within a few feet of the

TTL Project No. 2073502 Page 7 ground surface. Therefore, the groundwater conditions at the site may vary at different times of the year from those encountered during this investigation.

We recommend that the contractor determine the actual groundwater levels at the time of construction to assess groundwater impact on the construction procedure and suitable methods to address it.

TTL Project No. 2073502 Page 8

5.0 DESIGN RECOMMENDATIONS

The following conclusions and recommendations are based on our understanding of the proposed construction and on the data obtained during the field investigation. If the project information or location as outlined is incorrect or should change significantly, a review of these recommendations should be made by TTL. These recommendations are subject to the satisfactory completion of the recommended site and subgrade preparation and fill placement operations described in Section 6.0, “Construction Recommendations”.

5.1 Shallow Building Foundations

Based on the results of the field and laboratory testing for the borings performed for this investigation, the soils encountered at the anticipated foundation bearing depth (1.5 feet below the finished exterior grade in order to provide confinement) are expected to consist of predominantly medium dense native granular soils, but may possibly also encounter pockets exhibiting loose to very loose compactness. These soils are considered generally suitable for support of the proposed structure, provided in-place densification is performed, or removal and replacement is performed followed by backfilling with new engineered fill, to provide adequate bearing and reduce the risk of excessive settlement. Densification for the granular soils may be performed using a backhoe-mounted vibratory compactor (hoe-pac) or similar equipment.

If high groundwater levels are present at the time of construction, vibratory compaction may be detrimental to the prepared subgrade. Therefore, compaction under “static” operation would be required. If issues with controlling groundwater are encountered and if construction sequencing discussed in sections 5.8 of this report did not help to alleviate elevated groundwater conditions and achieve a more stable subgrade, it may be necessary to augment sump-and-pump operations with one or more wellpoints to facilitate construction dewatering. In the event excessive seepage is encountered during construction, TTL may be notified to evaluate whether other dewatering methods are required.

Prior to excavation of footings, we recommend that the entire building footprint and 10 feet beyond the building footprint be proof rolled/compacted using a vibratory smooth-drum roller as described in Section 6.1 due to the very loose/ loose granular soils encountered near the surface throughout the site. Compaction should be performed to improve the soil subgrade support conditions in building footings. It should be noted that footing excavation operations typically result in loosening of the bearing materials, which would require additional densification using a backhoe-mounted vibratory compactor (hoe-pac).

TTL Project No. 2073502 Page 9

Suitable compaction/bearing of native granular foundation soils can be verified as:

• Exhibiting a compacted (in-situ) dry density of at least 95 percent of the maximum dry density determined by Modified Proctor (ASTM D 1557) laboratory compaction,

• A dynamic cone penetrometer (DCP) reading of at least 8 blows per increment (average over three increments), or

• Other methods to demonstrate an equivalent SPT N-value of 10 bpf or greater.

If loose native granular soils are encountered that cannot be suitably re-compacted in-place, or other unsuitable foundation soils are encountered during foundation installation, over-excavation should extend through these materials to suitable bearing soils, with widening of the footing over-excavation as described below. The base of the over-excavation should be widened one foot for every foot of depth below the planned bearing depth, with the over-excavation centered along the footing. The over-excavated areas should be backfilled with dense-graded aggregate, placed in controlled lifts, and compacted to not less than 95 percent of the maximum dry density as determined by ASTM D 1557 (Modified Proctor).

Alternatively, the over-excavated areas could be backfilled with lean concrete having a minimum compressive strength of 1,500 pounds per square inch (psi) or other flowable controlled-density fill having a minimum compressive strength of 300 psi. If foundations will be placed at the base of the over-excavation or the lean concrete fill option will be utilized, widening the footing over-excavation will not be required. If the controlled-density fill option is utilized, the footing over-excavation shall be widened as discussed above.

Following the satisfactory completion of the site preparation and footing excavation inspections outlined in this report, the proposed structure may be supported on a conventional shallow foundation system. For strip (wall) footings and individual (square) footings, we recommend a net allowable bearing pressure of 3,000 pounds per square foot (psf). In using a net allowable soil pressure, the weight of the footings, backfill over the footings, or floor slabs need not be included in the structural loads for dimensioning footings. The bearing materials should be field-verified as being granular soils meeting the compaction/bearing criteria presented above and containing trace or less organics, or properly placed and compacted new engineered fill. A friction factor of 0.55 may be utilized along the face of the structures to mobilize sliding resistance between the installed structures and the existing granular soils.

Passive earth pressure resistance should be computed using an equivalent fluid pressure of 180 pounds per square foot per foot of depth, for granular backfill material. Resistance to sliding determined in accordance with the noted parameters should be considered available/ultimate

TTL Project No. 2073502 Page 10 resistance. Accordingly, the design for sliding resistance should include a factor of safety. We recommend that a factor of safety of at least 1.5 be used.

Inspection should be performed to verify that the exposed soil conditions at the bearing elevations are consistent with the subsurface conditions encountered in the test borings, loose granular soils have been suitably modified in-place, the bearing soils contain trace or less organics, and that the conditions are suitable for foundation bearing. Additionally, the presence of our engineer will help facilitate the timely remediation of unsuitable soil conditions. If the results of DCP or other strength tests indicate the exposed soil conditions are not suitable for the design bearing pressure, it may be necessary to increase the footing size to accommodate the lower bearing strengths or to over-excavate and backfill with engineered fill or flowable fill.

All footings should be constructed at a minimum depth of 1½ feet to provide confinement.

Wall (strip) footings should be at least 18 inches wide and column (square) footings should be at least 30 inches wide, regardless of sizing based on design loads and the recommended allowable bearing pressure. It should be noted that use of trench footings (i.e., placement of foundation concrete without forming) may not be feasible due to the presence of the upper profile granular soils, along with the need for in-place densification of loose granular bearing soils. Forming of footings and backfilling around CMU or poured foundation walls should be anticipated.

Utilizing the above allowable bearing pressure and proper foundation inspection techniques, the total settlement associated with the structure should not exceed 1 inch, and differential settlement should not exceed ¾ inch.

5.3 Subgrades

5.3.1 Existing Subgrade

The subgrades that would result upon the satisfactory completion of the site preparation as described in Section 6.0 of this report are considered generally suitable for support of the proposed pavements and floor slabs. Based on field data developed during this investigation, the subgrade soils consist of native granular soils. Visual descriptions of the upper profile soils indicate that the granular subgrade soils may be generally classified as Group A-3 in accordance with the American Association of State Highway and Transportation (AASHTO) system of soil classification. The granular soils are considered good to fair as subgrade materials.

TTL Project No. 2073502 Page 11

At the time of this investigation, the moisture contents in the upper 4 feet of the granular subgrade soils ranged from approximately 12 to 20 percent. These moisture contents are estimated to be slightly to significantly above the expected optimum moisture content for these soils. Therefore, remedial action should be anticipated to be required to adjust the moisture contents of the existing materials and achieve proper compaction of the subgrade. Remedial action should also be anticipated due to the very loose to loose compactness of the granular soils.

5.3.2 Modified Subgrade

If soils are dry of optimum, water should be uniformly mixed into the subgrade. Where soils wet of optimum are encountered, lowering the moisture content by scarification and aeration (discing and exposure to sun and wind) may be required. Very moist to wet soils will “pump” under the operation of heavy equipment, resulting in deep rutting and perhaps rendering the operation of grading and paving equipment difficult or impossible.

If the schedule does not allow for scarification and aeration, other methods of subgrade modification may be required in areas of high moisture content. Modification may be achieved by undercutting and replacement with granular subbase (possibly in combination with a geotextile separation layer or geogrid reinforcement), mixing stone into the subgrade, or treating the subgrade with lime or cement. The method of subgrade modification should be determined at the time of construction (See Section 6.1, “Construction Recommendations - Site and Subgrade Preparation”).

5.4 Floor Slabs

It is recommended that all floor slabs be “floating”, that is, fully ground supported and not structurally connected to walls or foundations. This is to reduce the possibility of cracking and displacement of the floor slabs because of differential movements between the slab and the foundation. Such movements could be detrimental to slabs that are rigidly connected to the foundations. There may be certain areas where it will be difficult or impractical to make the slab floating. In such areas, it may be necessary to increase the slab thickness and reinforcement to prevent the foundation from cracking the slab and settling independently.

For properly prepared subgrade soils, a modulus of subgrade reaction (k) of 165 pounds per cubic inch (pci) may be used for floor slab design. It is recommended that the floor slab be supported on a minimum 6-inch layer of relatively clean granular material such as sand and gravel or crushed stone. This is to help distribute concentrated loads and provide more uniform subgrade support beneath the slab.

TTL Project No. 2073502 Page 12

We recommend that, at a minimum, a vapor retarder for moisture control having a minimum thickness of 6 mils be provided beneath the floor slab. Construction and/or saw cut joints should be provided as necessary for crack control.

5.8 Groundwater Control

Encountered groundwater conditions were previously discussed in Section 4.3. As stated previously, groundwater level may approach within a few feet of the ground surface during the wet season or temporally perched from a rain event.

If excavations below the groundwater table are required (e.g., site utilities, foundations, etc.), or if seasonally elevated groundwater conditions are prevalent at the time of construction, diligent dewatering using point wells will be required for groundwater management during construction. In the event excessive seepage is encountered during construction, TTL may be notified to evaluate whether other dewatering methods are required. Installation of the proposed foundation and site utilities is expected to require excavation below the “normal” groundwater level. The soils below the groundwater table are expected to be predominantly granular soils and groundwater seepage into excavations should be anticipated.

Construction planning should include potential remedial measures to be implemented where excessive groundwater seepage or unstable subgrades are encountered in the proposed excavations. Dewatering methods may include multiple sumps or a system of well points. The type of dewatering system utilized will depend on construction practices, soil conditions encountered in the foundation excavations, seasonal conditions, and the depth of excavation.

Additionally, the contractor will need to exercise diligence to control seepage and runoff to maintain a stable subgrade. Installation of utilities early in the site development may also alleviate unstable subgrade conditions.

5.9 Excavations and Slopes

The sides of temporary excavations for building foundations, utility installations, and other construction should be adequately sloped to provide stable sides and safe working conditions.

Otherwise, the excavation must be properly braced against lateral movements. In any case, applicable Occupational Safety and Health Administration (OSHA) safety standards must be followed.

Based on the test borings, it is likely that excavations will OSHA Type C soils (granular soils).

For temporary excavations in Type C soils, side slopes must be no steeper than 1½ horizontal to 1 vertical (1.5H:1V). Flatter slopes may be required if lower strength soils or adverse seepage conditions are encountered during construction.

TTL Project No. 2073502 Page 13

For permanent excavation slopes, we recommend that grades be no steeper than 3H:1V without a more extensive geotechnical evaluation of the proposed construction plans and site conditions.

TTL Project No. 2073502 Page 14

6.0 CONSTRUCTION RECOMMENDATIONS

6.1 Site and Subgrade Preparation

Prior to proceeding with construction operations, all topsoil, root mat, vegetation, existing pavement, concrete curbs, existing canopy and associated foundation system, and other deleterious non-soil materials should be removed from the proposed construction areas.

Suitable topsoil may be stockpiled for later use in landscaped areas. Topsoil and pavement thicknesses may vary across the site. Dark soils having the appearance of topsoil, but exhibiting only root “hairs” or trace organics less than approximately five percent, may not require stripping for the full depth of the darkly colored zone, provided the subgrade can be satisfactorily proof rolled as described below. Conversely, the site may contain areas where additional excavation will be required beyond the darkly colored zone due to organics or high moisture in order to provide a stable subgrade for construction. The actual amount of required stripping should be determined in the field by a geotechnical engineer or qualified representative.

Upon completion of stripping and clearing, the areas intended to support floor slabs and new fill should be carefully inspected by a geotechnical engineer. At the time of inspection, the engineer should observe proof rolling/compaction of the granular subgrades using a vibratory, smooth- drum roller. The roller should make a minimum of two passes covering the proposed development area, with additional passes as necessary to achieve required compaction and/or subgrade stabilization.

The purpose of vibratory compaction for the granular soils is to densify zones of loose materials that are encountered in the upper portion of the soil profile, thereby providing more uniform subgrade support. We recommend a roller with a minimum dead weight on the drums of 8 tons, vibrating at 30 Hz or greater, and traveling at speeds not exceeding approximately 4 feet per second (about 3 miles per hour). These operational criteria should provide sufficient dynamic compaction energy to alleviate loose soil conditions within the zone of influence for subgrade support.

Any unsuitable materials observed during the inspection and proof-rolling operations should be undercut and replaced with compacted fill or stabilized in place utilizing conventional remedial measures such as discing, aeration, and recompaction. Once the site has been proof rolled, inspected, and stabilized, the proof-rolled or inspected subgrades should not be exposed to wet conditions.

TTL Project No. 2073502 Page 15

The results of the inspection and proof-rolling operations will be partially dependent on construction operations, the moisture content of the soil, and the weather conditions prevalent at the time. If pumping or rutting is encountered and difficulty is experienced in the operation of construction equipment, TTL should be notified in order to determine which method of subgrade modification may be best suited for the conditions encountered. Should such conditions be experienced, we may recommend that a small test area be used to determine the necessary depth of undercutting and stone replacement or other remedial action necessary to achieve a stable subgrade condition.

6.2 Fill

Material for engineered fill or backfill required to achieve design grades may consist of any non-organic soils having a maximum dry density as determined by the Modified Proctor (ASTM D 1557) of 90 pounds per cubic foot (pcf) or greater. To maintain the same subgrade support design values (k-value) presented in this report, fill placed to achieve subgrade elevations should consist of AASHTO A-1 series, A-2 series, or A-3 series soils (equivalent to USCS soil types GP, GW, SP and SW) . On-site soils may be re-used as engineered fill materials provided that they contain trace or less organic matter and debris, and are free of excessive moisture, and rock or stone fragments larger than 3 inches in diameter. Depending on seasonal conditions, the on-site soils may be wet of optimum and may require scarification and aeration to achieve satisfactory compaction. If the construction schedule does not allow for scarification and aeration activities, it may be more practical or economical to utilize imported granular fill.

Fill should be placed in uniform layers no more than 8 inches thick (loose measure) and adequately keyed into stripped and scarified soils. All fill within the building areas and pavement subgrades should be compacted to not less than 95 percent of the maximum dry density as determined by ASTM D 1557 (Modified Proctor).

The upper soil profile at the site consists of predominantly granular soils. The contractor should be prepared to use a vibratory, smooth-drum roller to provide effective compaction of the granular soils and new granular engineered fill.

Scarified subgrade soils and all fill material should be within 3 percent of the optimum moisture content to facilitate compaction. Furthermore, fill material should not be frozen or placed on a frozen base. It is recommended that all earthwork and site preparation activities be conducted under adequate specifications and properly monitored in the field by a qualified geotechnical testing firm.

TTL Project No. 2073502 Page 16

6.3 Foundation Excavations

As mentioned in Section 5.1, foundations used to support the structure should have a detailed footing inspection performed for each foundation. A geotechnical engineer or qualified representative should perform these inspections to verify that the exposed materials are similar to those encountered in the borings, loose granular soils have been suitably modified in-place, and that engineered fill has been properly placed and compacted such that it is capable of supporting the design bearing pressure.

We recommend that the foundation excavations be concreted as soon as practical after they are excavated and that water not be allowed to pond in any excavation. If it is necessary to leave the bearing surface open for any extended period of time, we recommend that a thin mat of lean concrete be placed over the bottom of the excavation to reduce damage to the surface from weather or construction. Foundation concrete should not be placed on frozen or saturated subgrade.

Additional foundation subgrade inspection and preparation recommendations are provided in Section 5.1.

TTL Project No. 2073502 Page 17

7.0 QUALIFICATION OF RECOMMENDATIONS

Our evaluation of foundation and slab design and construction conditions has been based on our understanding of the site and project information and the data obtained during our field investigation. The general subsurface conditions were based on interpretation of the subsurface data at specific boring locations. Regardless of the thoroughness of a subsurface investigation, there is the possibility that conditions between borings will differ from those at the boring locations, that conditions are not as anticipated by the designers, or that the construction process has altered the soil conditions. This is especially true for previously developed sites.

Therefore, experienced geotechnical engineers should observe earthwork and foundation construction to confirm that the conditions anticipated in design are noted. Otherwise, TTL assumes no responsibility for construction compliance with the design concepts, specifications, or recommendations.

The design recommendations in this report have been developed on the basis of the previously described project characteristics and subsurface conditions. If project criteria or locations change, a qualified geotechnical engineer should be permitted to determine whether the recommendations must be modified. The findings of such a review will be presented in a supplemental report.

The nature and extent of variations between the borings may not become evident until the course of construction. If such variations are encountered, it will be necessary to reevaluate the recommendations of this report after on-site observations of the conditions.

Our professional services have been performed, our findings derived, and our recommendations prepared in accordance with generally accepted geotechnical engineering principles and practices. This warranty is in lieu of all other warranties either expressed or implied. TTL is not responsible for the conclusions, opinions, or recommendations of others based on this data.

Plates

Plate 1.0 Site Location Map Plate 2.0 Test Boring Location Plan

Plate 1.0

REVISED: ---

Drawing No.:

Site Location Map

500' 1000'

Approximate Site Location

0'

DRAWN: IJH 8/10/2022

Notes: Aerial Basemap obtained From Google Earth and dated January 2022.

Specialized Engineering Solutions

Project No.: 2073502

Proposed EHRM Upgrades West Palm Beach VAMC, Florida

Legend:

25'0'

Test Boring Location Plan

Plate 2.0

REVISED: ---

Drawing No.:

B-1

50'

Proposed Test Boring Location

B-1

B-2

DRAWN: IJH 8/10/2022

Notes: Basemap Provided by Specialized Engineering Solutions and dated 06/17/2022 .

Specialized Engineering Solutions

Project No.: 2073502

Proposed EHRM Upgrades West Palm Beach VAMC, Florida

Approximate Extent of proposed Structure

APPENDIX A

Logs of Test Borings

1-2-1 (3)

2-4-6-8 (10)

6-9-7-8 (16)

5-4-3-3 (7)

4-4-4-2 (8)

2-1-3 (4)

7-3-4 (7)

4-8-11 (19)

NP

NP

NP

NP

NP

NP

NP

NP

NP

SS

1a

SS

1b

SS

SS

SS

SS

SS

SS

SS

TOPSOIL - 3 Inches 0.3'

Moist Very Loose Dark Brown SILTY SAND w/Trace Gravel and Organics (SM) @1.5': Brown/Gray @2': Loose, Dark Brown

4.0' Moist Medium Dense Brown POORLY GRADED SAND w/Trace Silt (SP)

6.0' Moist Loose Brown POORLY GRADED SAND w/Trace Silt

(SP)

@8': w/Silt (SP-SM)

@13.5': Very Loose, w/Trace Silt (SP)

@18.5': Loose

23.5' Moist Medium Dense Brown/Dark Brown POORLY GRADED SAND w/Trace Silt (SP)

NOTES

LOGGED BY KKC

AT TIME OF DRILLING 6.0 ft / Elev 8.0 ft

AT END OF DRILLING None

0hrs AFTER DRILLING Backfilled w/ bentonite grout

GROUND WATER LEVELS:

CHECKED BY IJH

GROUND ELEVATION 14 ftRIG NO. CME 75DRILLING CONTRACTOR Terracon HEL BEL

DRILLING METHOD 3 1/4" HSA/Rotary Wash

DATE STARTED 7/15/22 COMPLETED 7/15/22

(Continued Next Page)

E

LE

V A

T

IO

N (f t)

-5

-10

D E

P T

H (f t)

G R

A P

H

IC

LO

G

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

U N

C O

N F

. C O

M P

S

T R ts f)

D R

Y U

N

IT

W T

(p cf

SPT N VALUE

20 40 60 80

S A

M P

LE

T

Y P

E N

U M

B E

R

20 40 60 80

PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-1

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

T T

L_ G

E O

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TTL Associates, Inc.

1915 N 12th Street Toledo, Ohio 43624 Telephone: 419-324-2222 Fax: 419-241-1808

4-5-11 (16)

6-8-11 (19)

1-2-1 (3)

7-15-19 (34)

13-24-29 (53)

NP

NP

NP

NP

NP

SS

SS

SS

SS

SS

@28.5': Brown

38.5' Moist Very Loose Dark Gray POORLY GRADED SAND w/Trace Silt (SP)

43.5' Moist Dense Gray POORLY GRADED SAND w/Trace Silt

(SP)

@48.5': Very Dense

50.0' Bottom of hole at 50.0 feet.

E

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V A

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N (f t)

-15

-20

-25

-30

-35

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H (f t)

G R

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LO

G

R E

C O

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R Y

(R

Q D

B

LO

W C

O U

N T

S (N

V A

LU

E

U N

C O

N F

. C O

M P

S

T R ts f)

D R

Y U

N

IT

W T

(p cf

SPT N VALUE

20 40 60 80

S A

M P

LE

T

Y P

E N

U M

B E

R

20 40 60 80

PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-1

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

T T

L_ G

E O

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1915 N 12th Street Toledo, Ohio 43624 Telephone: 419-324-2222 Fax: 419-241-1808

7-5

5-6-6-5 (12)

2-2-1-1 (3)

1-1-1-1 (2)

1-1-0-0 (1)

1-1-2-1 (3)

1-1-2 (3)

1-2-2 (4)

2-3-4 (7)

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

SS

1a

SS

1b

SS

1c

SS

SS

SS

SS

SS

SS

SS

SS

CONCRETE - 3.5 Inches 0.3'

CRUSHED STONE - 3 Inches 0.5'

Moist Medium Dense Dark Brown POORLY GRADED SAND w/Trace Silt (SP) @2': w/Silt

4.0' Moist Very Loose Dark Brown POORLY GRADED SAND w/Silt and Trace Gravel (SP-SM)

@6': w/Trace Silt and Gravel (SP)

@8': Dark Brown/Brown

@10': Brown

@13.5': Wet, (Free Water Noted in Jar)

@23.5': Wet, Loose, (Free Water Noted in Jar)

NOTES

LOGGED BY KKC

AT TIME OF DRILLING 4.0 ft / Elev 10.0 ft

AT END OF DRILLING None

0hrs AFTER DRILLING Backfilled w/ bentonite grout

GROUND WATER LEVELS:

CHECKED BY IJH

GROUND ELEVATION 14 ftRIG NO. CME 75DRILLING CONTRACTOR Terracon HEL BEL

DRILLING METHOD 3 1/4" HSA/Rotary Wash

DATE STARTED 7/15/22 COMPLETED 7/15/22

(Continued Next Page)

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S (N

V A

LU

E

U N

C O

N F

. C O

M P

S

T R ts f)

D R

Y U

N

IT

W T

(p cf

SPT N VALUE

20 40 60 80

S A

M P

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T

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B E

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20 40 60 80

PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-2

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

T T

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TTL Associates, Inc.

1915 N 12th Street Toledo, Ohio 43624 Telephone: 419-324-2222 Fax: 419-241-1808

5-8-9 (17)

5-5-6 (11)

17-30-31 (61)

12-17-21 (38)

17-27-30 (57)

NP

NP

NP

NP

NP

SS

SS

SS

SS

SS

28.5' Wet Medium Dense Brown POORLY GRADED SAND w/Trace Silt (SP) (Free Water in Jar Noted)

@33.5': w/Silt (SP-SM)

38.5' Moist Very Dense Gray POORLY GRADED SAND w/Trace Silt (SP)

@43.5': Dense

@48.5': Very Dense

50.0' Bottom of hole at 50.0 feet.

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S (N

V A

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U N

C O

N F

. C O

M P

S

T R ts f)

D R

Y U

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W T

(p cf

SPT N VALUE

20 40 60 80

S A

M P

LE

T

Y P

E N

U M

B E

R

20 40 60 80

PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-2

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

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1915 N 12th Street Toledo, Ohio 43624 Telephone: 419-324-2222 Fax: 419-241-1808

APPENDIX B

Legend Key

2073502 - Legend -Proposed EHRM Upgrades.doc

Notes:

1. Exploratory borings were drilled on July 15, 2022 using mud rotary drilling technique. The borings were advanced utilizing 3¼-inch outside diameter hollow-stem augers along with a 2- 7/8 -inch diameter tricone roller bit.

2. These logs are subject to the limitations, conclusions, and recommendations in the report and should not be interpreted separate from the report.

3. The borings were located in the field by TTL in accordance with a proposed Boring location plan attached to the proposal.

4. Ground Surface Elevations were depicted from Google Earth and reported to the nearest foot.

5. Unconfined Compressive Strength (tsf):

NP = Non Plastic

APPENDIX C

Tabulation of Test Data

B-1 0.0 NP NP NP 12.5 15 SM 18.1

B-1 1.5 19.5

B-1 2.0 17.2

B-1 4.0 16.3

B-1 6.0 18.6

B-1 8.0 20.2

B-1 13.5 20.9

B-1 18.5 14.6

B-1 23.5 18.6

B-1 28.5 20.1

B-1 33.5 19.8

B-1 38.5 24.9

B-1 43.5 24.5

B-1 48.5 22.8

B-2 0.0 5.6

B-2 0.5 12.3

B-2 1.0 14.0

B-2 2.0 19.8

B-2 4.0 26.0

B-2 6.0 NP NP NP 12.5 4 SP 30.0

B-2 8.0 22.4

B-2 10.0 19.8

B-2 13.5 20.5

B-2 18.5 19.5

B-2 23.5 20.5

B-2 28.5 20.7

B-2 33.5 27.4

B-2 38.5 23.0

B-2 43.5 24.5

B-2 48.5 26.4

SUMMARY OF LABORATORY RESULTS

Plastic Limit

Plasticity Index

Maximum Size (mm)

%<#200 Sieve

Liquid Limit

Satur-ation

Void Ratio

Class-ification

Water Content

Dry Density

(pcf) DepthBorehole

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

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TTL Associates, Inc.

1915 N 12th Street Toledo, Ohio 43624 Telephone: 419-324-2222 Fax: 419-241-1808

APPENDIX D

Laboratory Test Results

0 20 40 60 80 100

B-1

B-2

ML

CL

MH

CH

Specimen Identification

CL-ML

P L A S T I C I T Y

I N D E X

LIQUID LIMIT

Fines Classification

NP

NP

NP

NP

SILTY SAND (SM)

POORLY GRADED SAND (SP)

LL PL PI

0.0

6.0

NP

NP

ATTERBERG LIMITS' RESULTS

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

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1915 N 12th Street Toledo, Ohio 43624

0.0010.010.1110100

PI Cc

NP

NP

NP

NP

CuLL PL

NP

NP

GRAIN SIZE DISTRIBUTION

COBBLES

GRAVEL

0.0

6.0

10.6

3.1

12.5

12.5

P E

R C

E N

T F

IN

E

R B

Y W

E

IG

H T

SAND

GRAIN SIZE IN MILLIMETERS

coarse fine

0.0

6.0

SILTY SAND (SM)

POORLY GRADED SAND (SP)

Specimen Identification

Specimen Identification D100 D60 D30 D10 %Gravel

0.347

0.319

15.4

4.0

B-1

B-2 coarse

SILT OR CLAY

finemedium

%Sand %Silt %Clay

0.178

0.187

0.033

0.102

1.6

0.5

83.0

95.5

0.0

0.0

3 100

B-1

B-2

24 16 30

1 2006 10 501/2

HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS

1403 4 20 406 601.5 8 143/4 3/8

2.8

1.1

USCS Classification

CLIENT Specialized Engineering Solutions

PROJECT NUMBER 2073502

PROJECT NAME Proposed EHRM Upgrades

PROJECT LOCATION West Palm Beach, FL

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1915 N 12th Street Toledo, Ohio 43624