Attachment 11 - 556-402 SPS 100CD Reports 29NOV22.pdf

100% CONSTRUCTION DOCUMENTS

REPORTS

November 29, 2022

Expand Sterile Processing Services

(SPS)

Capt. James A. Lovell Federal Health Care Center

3001 Green Bay Road, BLDG 133CA North Chicago, Illinois 60064-3048

VA Project #556-402 Alesia Project #2021-22

Geotechnical Subsurface Investigation

Geotechnical Subsurface Investigation Addendum

NESHAP Asbestos Survey

Physical Security Design Guidance

Electrical Metering Survey

HVAC Equipment Test & Balance Report SPD Oxygen Line Inspection

(This page is left blank intentionally)

Project 556-402 Expand SPS Captain James A Lovell FHCC VA Medical Center

North Chicago, Illinois

Alesia Architecture

Elkhorn, Nebraska

February 14, 2022

TTL Project No. 2154202

TTL Associates, Inc.

1915 North 12th Street Toledo, OH 43604-5305 419-342-2222 www.ttlassoc.com file://///tol-dfs1.ttl.local/dfs/Testing/Projects/2131201%20-%20Method%20Architecture%20-%20Proposed%20Oil%20Change%20Facility%20Addition%20-%20Toledo%20Ohio/Reports%20and%20Other%20Deliverables/Parts/www.ttlassoc.com

GEOTECHNICAL SUBSURFACE INVESTIGATION

PROJECT 556-402 – EXPAND SPS

BUILDING 133CA – 1ST FLOOR

CAPTAIN JAMES A LOVELL FHCC VA MEDICAL CENTER

NORTH CHICAGO, IL

FOR

ALESIA ARCHITECTURE

3705 NORTH 200TH STREET

ELKHORN, NEBRASKA 68022

SUBMITTED

FEBRUARY 14, 2022

TTL PROJECT NO. 2154202

TTL ASSOCIATES, INC.

1915 NORTH 12TH STREET

TOLEDO, OHIO 43604

(419) 324-2222

(419) 321-6257 FAX

Alesia Architecture February 2022 TTL Project No. 2154202 Page i

TABLE OF CONTENTS

Page No.

1.0 INTRODUCTION

2.0 INVESTIGATIVE PROCEDURES

3.0 PROPOSED CONSTRUCTION

4.0 GENERAL SITE AND SUBSURFACE CONDITIONS

4.1 General Site Conditions

4.2 General Soil Conditions

4.3 Groundwater Conditions

5.0 DESIGN RECOMMENDATIONS

5.1 Shallow Building Foundations

5.3 Seismic Site Class

5.4 Subgrades

5.4.1 Existing Subgrade

5.4.2 Modified Subgrade

5.5 Floor Slabs

5.6 Groundwater Control and Drainage

5.7 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

FIGURES

Logs of Test Borings B-1 through B-4

Legend Key

Tabulation of Test Data

Grain Size Distribution

TTL Project No. 2154202 Page 1

1.0 INTRODUCTION

This geotechnical subsurface investigation report has been prepared for the construction of an addition to building 133CA to expand the Sterile Processing Service (SPS) in North Chicago, Illinois. 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. 2154202, dated September

16, 2021, and authorized by Richard J. Onken with Alesia Architecture on December 2, 2021.

An additional boring was added to the scope and performed in accordance with Change Order

No. 1, dated December 15, 2021, performed based on verbal authorization by Colonel Onken during the December 8, 2021 design team meeting.

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

This investigation included four 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 floor slab construction, and related field testing.

An Asbestos Survey was performed by TTL and submitted under separate cover. This investigation did not include an environmental assessment of the subsurface materials at the site.

TTL Project No. 2154202 Page 2

2.0 INVESTIGATIVE PROCEDURES

This subsurface investigation included four test borings drilled by TTL on January 11 and 12, 2022. Borings designated as B-1 through B-4 were drilled in the general area of the proposed addition. The test borings were located in the field by TTL based on a proposed boring location plan in consultation with Alesia Architecture. The approximate locations of the borings, as well as the approximate location of the existing building, are shown on the Test Boring

Location Plan (Plate 2.0).

Ground surface elevations were estimated to the nearest foot based on topographic contours shown on the plan drawing provided by Calibre Engineering on February 14, 2022.

The test borings were performed in general accordance with geotechnical investigative procedures outlined in ASTM Standards D 1452 and D 5434. The test borings performed during this investigation were drilled with a track-mounted drilling rig utilizing 3¼-inch inside diameter hollow-stem augers. Borings B-1, B-2, and B-4 were extended to the planned termination depth of 25 feet below existing grade. Boring B-3 was extended to the planned termination depth of 100 feet.

During auger advancement, soil samples were generally collected at 2½-foot intervals to a depth of 10 feet and at 5-foot intervals thereafter. 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 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 shipped 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 were tested in our laboratory for moisture content (ASTM D 2216). Dry density determinations and unconfined compressive strength tests by the constant rate of strain method (ASTM D 2166) were performed on selected intact cohesive samples. Unconfined compressive strength estimates were performed on the remaining intact cohesive split-spoon samples using a calibrated hand penetrometer. Particle size analyses (ASTM D 6913 and D 7928) and Atterberg

TTL Project No. 2154202 Page 3 limits tests (ASTM D 4318) were performed on representative samples from Borings B-1

(SS-3), B-3 (SS-1), and B-4 (SS-5) to determine soil classification and soil index properties.

The test results are presented on the Logs of Test Borings, Tabulation of Test Data sheets, and

Grain Size Distribution sheet attached to this report.

Soil conditions encountered in the test borings are presented in the Logs of Test Borings, along with information related to sample data, SPT results, water conditions observed in the borings, and laboratory test data. It should be noted that these logs have been prepared on the basis of laboratory classification and testing as well as field logs of the encountered soils.

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. 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 subsurface conditions differ from those anticipated prior to the start of construction.

TTL Project No. 2154202 Page 4

3.0 PROPOSED CONSTRUCTION

The proposed construction consists of an addition to building 133CA to expand the Sterile

Processing Service (SPS). The proposed addition is anticipated to be a 15,000 square feet 2 story structure, slab-on-grade structure supported on a conventional shallow foundation system consisting of wall (strip) and/or column (square) footings. Structural loads were not provided, but are assumed to be light to moderate in magnitude. Maximum wall loads and column loads are assumed to not exceed 4,000 pounds per lineal foot (plf) and 150 kips, respectively.

We understand that the new SPS addition finish floor will match the existing basement finish floor level, which approximates existing grade. The proposed crawl space (pipe basement) for the new addition and utility tunnel/tramway is planned at approximately 7 feet below existing grades. Based on review of plans for the existing building and tramway, footings are anticipated at depths on the order of 2 feet below the crawl space.

Final grades are assumed to approximate existing grades.

TTL Project No. 2154202 Page 5

4.0 GENERAL SITE AND SUBSURFACE CONDITIONS

4.1 General Site Conditions

The site is located on the east side of building number133CA, north of the intersection of

K Street with L Street. At the time of this investigation, the site contained a grass lawn with concrete sidewalks.

The surface materials encountered in all of the borings consisted of consisted of topsoil varying in thickness from approximately 3 to 8 inches.

4.2 General Soil Conditions

Based on the results of our field and laboratory tests, the subsoils encountered underlying the topsoil consisted of predominantly stiff to very stiff native cohesive soils, with occasional zones of granular soils.

While Borings B-1 and B-3 were performed within close proximity of the existing building and within the expected slope layback zone for the existing 9-foot-deep foundations, the uppermost soils (encountered to a depth of 3½ feet below existing grade) did not contain deleterious materials or other signs of uncontrolled fill, and had strength and moisture conditions similar to existing site soils. As such, these soils may be considered “possible fill.”

The native cohesive soils consisted of lean clay (CL) with sand and typically trace gravel, sandy silt (ML) with typically trace gravel, as well as silty clay with sand and trace gravel (CL-

ML). SPT N-values generally ranged from 9 to 27 blows per foot (bpf). Unconfined compressive strengths generally ranged from 2,000 to 7,500 pounds per square foot (psf).

Moisture contents varied from 15 to 23 percent. Liquid limits 24 to 36 percent and plasticity indices of 14 to 19 19 percent were determined for samples obtained from this stratum in

Borings B-1 (SS-3), B-3 (SS-1), and B-4 (SS-5. These values, along with gradation results, are indicative of lean clay (CL) with sand in accordance with USCS designations.

Zones of granular soils were encountered in Boring B-3 from approximately 43½ to 48½ feet and from 78½ to 83½ feet. The granular soils consisted of poorly graded sand (SP) with trace gravel, as well as poorly graded sand with silt (SP-SM) and trace gravel. SPT N-values of 19 bpf and 53 bpf were determined for these zones, indicating medium dense and very dense compactness, and moisture contents were on the order of 21 percent and 11 percent.

TTL Project No. 2154202 Page 6

Additional descriptions of the stratigraphy encountered in the borings are presented on the

Logs of Test Borings.

4.3 Groundwater Conditions

Groundwater was neither initially encountered during drilling nor observed upon completion of drilling operations in any of the borings performed for this investigation. It should be noted that each of the borings was drilled and backfilled within the same day, and stabilized water levels may not have occurred over this limited period. Instrumentation was not installed to observe long-term groundwater levels.

Based on the limited data available, such as the soil characteristics and the moisture conditions encountered in the borings, it is our opinion that the “normal” groundwater level may be encountered at depths on the order of 8 feet or greater below existing grades. 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. Therefore, the groundwater conditions may vary at different times of the year from those encountered during this investigation.

TTL Project No. 2154202 Page 7

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

We understand that the new SPS addition finish floor will match the existing basement finish floor level, which approximates existing grade. The proposed crawl space (pipe basement) for the new addition and utility tunnel/tramway is planned at approximately 7 feet below existing grades. Based on review of plans for the existing building and tramway, footings are anticipated at depths on the order of 2 feet below the crawl space.

Based on the results of the field and laboratory testing for the borings performed in the general area of the proposed building footprint, soils at the anticipated bearing depths are anticipated to consist of predominantly stiff to very stiff native cohesive soils, which are considered generally suitable for support of the proposed foundations.

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. Shallow foundations may be designed utilizing a gross allowable bearing pressure of 3,250 pounds per square foot (psf) for strip and square footings. The bearing materials should be field-verified as being cohesive soils exhibiting a minimum unconfined compressive strength of 3,000 psf, or properly placed and compacted new engineered fill.

Due to the existing site development, it is particularly important that a detailed foundation excavation inspection be completed by a TTL geotechnical engineer or qualified representative. 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 and 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 hand penetrometer 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

TTL Project No. 2154202 Page 8 accommodate the lower bearing strengths or to over-excavate and backfill with engineered fill or flowable fill.

If unsuitable foundation soils are encountered, over-excavation should extend through these materials to suitable bearing soils. In all cases, the base of the over-excavation should be widened on foot for every foot of depth below the proposed bearing elevation, with the 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 100 percent of the maximum dry density as determined by ASTM D 698 (Standard 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.

All exterior footings and footings in unheated areas should be constructed at a minimum frost penetration depth of 40 inches below finished exterior grades. Interior footings may bear at a convenient depth below the floor slab provided they bear on native soils as described above or compacted engineered fill. 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.

Utilizing the above allowable bearing pressures and proper foundation inspection techniques, the total settlement associated with the structure should not exceed ½ inch. It should be noted that the total settlement associated with the new addition will be differential settlement with respect to the existing structure. However, the magnitude of settlement indicated above is anticipated to be within allowable limits.

5.2 Below-Grade Walls

For below-grade walls that are restrained from rotation and are considered rigid and non-yielding, lateral earth pressures should be assumed for “at-rest” conditions. An at-rest lateral earth pressure coefficient (ko) of 0.50 should be used along with a soil unit weight of

125 pounds per cubic foot (pcf) in determining the lateral pressure acting on the walls. For retaining structures or below-grade walls that are not restrained at the top of the wall, an active lateral earth pressure coefficient (ka) of 0.33 may be used for design. Alternatively, equivalent

TTL Project No. 2154202 Page 9 fluid weights of 65 and 45 pcf may be used for at-rest and active case designs, respectively.

These values are based on the assumption that the existing cohesive soils encountered in the upper portion of the subsurface profile will constitute the major portion of the backfill area and retained earth behind the walls. If lower lateral earth pressures are preferred for structural design considerations, a select granular backfill material should be specified, and earth pressure coefficients can be adjusted accordingly.

The above earth pressure coefficients and/or equivalent fluid weights do not include hydrostatic pressures on the wall(s). We recommend that a foundation drain be placed at the footing level around the perimeter of each wall to prevent water build-up behind the below-grade walls. The aggregate around the foundation drain should be designed to prevent clogging from silt and clay-size particles. For drainage purposes, backfill immediately behind below-grade walls should consist of clean, granular material with less than 8 percent finer than the No. 200 sieve. The thickness of the drainage backfill zone should be at least 24 inches behind the wall at the base. The foundation drains should operate under gravity discharge to a sump-and-pump system that is installed for long-term groundwater control.

5.3 Seismic Site Class

We have reviewed seismic design parameters in accordance with International Building Code

(IBC) criteria. Based on IBC Section 1613.3.2, which references ASCE 7, utilizing the SPT

N-value method, the weighted average N-value for the profile was calculated to be greater than

15 blows per foot (bpf) but less than 50 bpf. Based on this average N-value, the site can be characterized as Site Class D (soft soil) in accordance with ASCE 7 Table 20.3-1.

5.4 Subgrades

5.4.1 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 acceptable for support of the proposed floor slabs. Based on field and laboratory data developed during this investigation, the subgrade soils consist of native cohesive soils, although zones of cohesive existing fill materials may also be encountered. Subgrade soils may also consist of new engineered fill utilized to achieve design grades. The predominantly cohesive site soils will dictate floor slab design.

Laboratory analyses for Borings B-1 (SS-3), B-3 (SS-1), and B-4 (SS-5), as well as visual descriptions of the upper profile indicate that the cohesive subgrade soils may be generally

TTL Project No. 2154202 Page 10 classified as Group A-6 or better in accordance with the American Associates of State Highway and Transportation Office (ASHTO) system of soil classification. These soils are considered fair to poor as subgrade materials because they have relatively low permeabilities and a high percentage of silt and clay particles, which makes them susceptible to moisture, frost penetration and frost heave.

At the time of this investigation, the moisture contents in the upper 2½ feet of the cohesive subgrade soils at the crawl space/pipe basement level generally ranged from approximately 14 to 17 percent. These moisture contents are estimated to vary from near to somewhat above the expected optimum moisture content for these soils. Therefore, remedial action may be needed to adjust the moisture contents of the existing materials and achieve proper compaction of the subgrade.

5.4.2 Modified Subgrade

If soils are dry of optimum, water should be uniformly mixed into the subgrade. Where soils are wet of optimum, lowering the moisture content by scarification and aeration (discing and exposure to sun and wind) may be required. However, this may not be feasible if construction occurs during wet seasonal conditions. 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.

Therefore, 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 cement. The method of subgrade modification should be determined at the time of construction (See Section 6.1, “Construction

Recommendations - Site and Subgrade Preparation”).

5.5 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.

TTL Project No. 2154202 Page 11

For properly prepared subgrade soils, a modulus of subgrade reaction (k) of 135 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.

5.6 Groundwater Control and Drainage

As stated previously, groundwater was neither initially encountered during drilling nor observed upon completion of drilling operations in any of the borings performed for this investigation. Based on the limited data available, such as the soil characteristics and the moisture conditions encountered in the borings, it is our opinion that the “normal” groundwater level may be encountered at depths on the order of 8 feet or greater below existing grades.

It is our experience that adequate control of groundwater seepage, perched water, or surface water run-off into shallow excavations should be achievable by minor dewatering systems, such as pumping from prepared sumps. In the event excessive seepage is encountered during construction, TTL may be notified to evaluate whether other dewatering methods are required.

5.7 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.

The soils encountered during this investigation, within the anticipated depths of excavation, consist of the following OSHA Type soils:

• OSHA Type A soils (cohesive soils with unconfined compressive strengths of

3,000 pounds per square foot (psf) or greater),

• OSHA Type B soils (cohesive soils with unconfined compressive strengths greater than

1,000 psf but less than 3,000 psf), and

• OSHA Type C soils (existing fill materials).

TTL Project No. 2154202 Page 12

For temporary excavations in Type A, B, and C soils, side slopes must be no steeper than

¾ horizontal to 1 vertical (¾H:1V), 1H:1V, and 1½H:1V, respectively. For situations where a higher strength soil is underlain by a lower strength soil and the excavation extends into the lower strength soil, the slope of the entire excavation is governed by that required by the lower strength soil. In all cases, flatter slopes may be required if lower strength soils or adverse seepage conditions are encountered during construction.

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. 2154202 Page 13

6.0 CONSTRUCTION RECOMMENDATIONS

6.1 Site and Subgrade Preparation

Prior to proceeding with construction operations, all pavements, sidewalks, topsoil, root mat, vegetation, and other deleterious non-soil materials should be removed from the proposed construction areas. Suitable topsoil may be stockpiled for later use in landscape areas. Topsoil thicknesses may vary across the site, and topsoil quantities may be limited due to the existing development. 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.

Where utility trench abandonment is required, any remaining voids should be backfilled with engineered fill, placed in controlled lifts and tested for suitable compaction in accordance with the criteria in Section 6.2 of this report. If such excavations are randomly filled or graded without compaction control, excessive differential settlement could occur.

Upon completion of stripping and clearing, the areas intended to support floor slabs, new fill, and pavements should be carefully inspected by a geotechnical engineer. At that time, the engineer may require proof rolling of the cohesive soil subgrades utilizing a 20- to 30-ton loaded truck or other pneumatic-tired vehicle of similar size and weight. The truck should make a minimum of two passes in each of two perpendicular directions covering the proposed development area, with additional passes as necessary to achieve required compaction and/or subgrade stabilization.

The purpose of proof rolling the cohesive soils is to locate any weak, soft, or excessively wet materials that may be present at the time of construction. 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. It should be recognized that during periods of wet weather, the clayey soils that will be exposed at design subgrades will tend to pond water for short periods of time, with the potential to deteriorate the prepared subgrade.

TTL Project No. 2154202 Page 14

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 Standard Proctor

(ASTM D 698) of 90 pounds per cubic foot (pcf) or greater. To maintain the recommended subgrade support value (k-value) presented in this report, new engineered fill within 36 inches of subgrade elevation should consist of AASHTO A-6 or better soils. On-site soils may be used as engineered fill materials provided that they are free of organic matter, debris, 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 100 percent of the maximum dry density as determined by ASTM D 698 (Standard Proctor).

The upper soil profile at the site consists of native cohesive soils and potentially cohesive existing fill materials. Additionally, subgrades may consist of new engineered fill utilized to achieve design grades. The contractor should be prepared to use a sheepsfoot roller to provide effective compaction of the cohesive subgrade soils. For and granular engineered fill, a vibratory, smooth-drum roller would provide effective compaction of these materials. In narrow utility or footing excavations, the on-site cohesive soils may be difficult to compact;

therefore, a clean granular material may be required in these areas.

TTL Project No. 2154202 Page 15

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.

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, 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 modification recommendations are provided in

Section 5.1.

TTL Project No. 2154202 Page 16

7.0 QUALIFICATION OF RECOMMENDATIONS

Our evaluation of foundation and floor 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 potential is increased at 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.

2-5-4 (9)

5-8-11 (19)

12-12-13 (25)

3-5-6 (11)

3-4-5 (9)

3-3-5 (8)

2-5-9 (14)

1.68

4.50

2.56

2.29

2.00

1.02

2.18

SS

SS

SS

SS

SS

SS

SS

TOPSOIL - 8 Inches 0.7'

Moist Stiff Gray/Brown SANDY LEAN CLAY w/Gravel and Trace Organics (CL) (Possible Fill)

3.5' Moist Very Stiff to Hard Brown SANDY SILT w/Trace Gravel (ML)

5.0' Moist Very Stiff Brown LEAN CLAY w/Sand and Trace Gravel (CL)

@8.5': Stiff to Very Stiff, Gray

15.0' Moist Medium Stiff to Stiff Gray LEAN CLAY w/Sand and Trace Gravel (CL)

23.5' Moist Stiff to Very Stiff Gray SANDY SILTY CLAY w/Trace Gravel (CL-ML)

25.0' Bottom of hole at 25.0 feet.

NOTES

LOGGED BY KKC

AT TIME OF DRILLING None

AT END OF DRILLING None

0hrs AFTER DRILLING Backfilled w/Cuttings and Bentonite Chips

GROUND WATER LEVELS:

CHECKED BY KCH

GROUND ELEVATION 707 ftRIG NO. D70DRILLING CONTRACTOR TTL Associates, Inc. TB CW

DRILLING METHOD 3-1/4 in. HSA

DATE STARTED 1/11/22 COMPLETED 1/11/22

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PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-1

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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4-5-6 (11)

5-5-9 (14)

9-10-12 (22)

6-9-9 (18)

6-7-5 (12)

3-4-7 (11)

3-6-11 (17)

3.50

3.83

4.00

2.50

1.25

1.99

3.10

SS

SS

SS

SS

SS

SS

SS

TOPSOIL - 5 Inches 0.4'

Moist Stiff to Very Stiff Brown SANDY LEAN CLAY w/Trace Gravel (CL)

3.5' Moist Very Stiff Brown SANDY SILT w/Trace Gravel (ML)

@6': Very Stiff to Hard, w/Rock Fragments

@7.5': Very Stiff

13.5' Moist Stiff Gray LEAN CLAY w/Sand and Trace Gravel (CL)

@23.5': Very Stiff

25.0' Bottom of hole at 25.0 feet.

NOTES

LOGGED BY KKC

AT TIME OF DRILLING None

AT END OF DRILLING None

0hrs AFTER DRILLING Backfilled w/Cuttings and Bentonite Chips

GROUND WATER LEVELS:

CHECKED BY KCH

GROUND ELEVATION 707 ftRIG NO. D70DRILLING CONTRACTOR TTL Associates, Inc. TB CW

DRILLING METHOD 3-1/4 in. HSA

DATE STARTED 1/11/22 COMPLETED 1/11/22

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U M

B E

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20 40 60 80

PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-2

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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4-6-9 (15)

4-7-10 (17)

9-10-12 (22)

3-6-9 (15)

3-4-5 (9)

2-3-6 (9)

3-4-8 (12)

3.55

4.00

>4.5

3.79

1.98

1.59

1.53

SS

SS

SS

SS

SS

SS

SS

TOPSOIL - 3 Inches 0.3'

Moist Stiff to Very Stiff Dark Brown LEAN CLAY w/Sand, Trace Gravel, and Organics (CL) (Possible FIll)

3.5' Moist Very Stiff to Hard Brown SANDY SILT w/Trace Gravel (ML)

@6': w/Gravel

8.5' Moist Stiff to Very Stiff Gray LEAN CLAY w/Sand and Trace Gravel (CL)

@10': Stiff

NOTES

LOGGED BY KKC

AT TIME OF DRILLING None

AT END OF DRILLING None

0hrs AFTER DRILLING Backfilled w/Cuttings and Bentonite Chips

GROUND WATER LEVELS:

CHECKED BY KCH

GROUND ELEVATION 707 ftRIG NO. D70DRILLING CONTRACTOR TTL Associates, Inc. TB CW

DRILLING METHOD 3-1/4 in. HSA

DATE STARTED 1/12/22 COMPLETED 1/12/22

(Continued Next Page)

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MATERIAL DESCRIPTION

BORING NUMBER B-3

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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6-7-11 (18)

4-8-11 (19)

5-7-10 (17)

8-9-10 (19)

7-13-21 (34)

5-9-11 (20)

3.00

2.50

2.00

NP

>4.5

2.29 115

SS

SS

SS

SS

SS

SS

@28.5': Very Stiff

@35': Stiff to Very Stiff

43.5' Moist Medium Dense Gray SILTY SAND w/Trace Gravel

(SM)

48.5' Moist Hard Gray SILTY CLAY w/Sand and Trace Gravel

(CL-ML)

53.5' Moist Very Stiff Gray SILTY CLAY w/Sand and Trace Gravel (CL-ML)

@55': Stiff to Very Stiff

(Continued Next Page)

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20 40 60 80

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PL LLMC

MATERIAL DESCRIPTION

BORING NUMBER B-3

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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5-6-9 (15)

7-12-17 (29)

5-8-12 (20)

7-12-15 (27)

18-25-28 (53)

12-17-17 (34)

3.12

>4.5

2.50

3.75

NP

2.84

SS

SS

SS

SS

SS

SS

63.5' Moist Very Stiff to Hard Gray SILTY CLAY w/Sand and Trace Gravel (CL-ML)

@65': Very Stiff

78.5' Moist Very Dense Gray POORLY GRADED SAND w/Silt and Trace Gravel (SP-SM)

83.5' Moist Very Stiff to Hard Gray SILTY CLAY w/Sand and Trace Gravel (CL-ML)

(Continued Next Page)

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MATERIAL DESCRIPTION

BORING NUMBER B-3

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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15-21-30 (51)

8-10-11 (21)

17-11-20 (31)

>4.5

1.93

NI

SS

SS

SS

93.5' Moist Stiff to Very Stiff Gray SILTY CLAY w/Sand and Trace Gravel (CL-ML)

98.5' Moist Hard Gray SILT w/Sand and Trace Gravel (ML)

100.0' Bottom of hole at 100.0 feet.

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MATERIAL DESCRIPTION

BORING NUMBER B-3

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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2-2-3 (5)

3-6-8 (14)

2-12-15 (27)

6-8-10 (18)

4-6-8 (14)

3-3-5 (8)

3-4-8 (12)

1.00

4.42

>4.5

>4.5

1.81

1.65

1.62

SS

SS

SS

SS

SS

SS

SS

TOPSOIL - 5 Inches 0.4'

Moist Medium Stiff to Stiff Brown LEAN CLAY w/Sand, Trace Gravel, and Organics (CL)

3.5' Moist Stiff Brown SANDY SILT w/Trace Gravel (ML)

6.0' Moist Very Stiff to Hard Brown SILTY CLAY w/Sand and Trace Gravel (CL-ML)

@8.5': Gray

10.0' Moist Stiff Gray LEAN CLAY w/Sand (CL)

18.5' Moist Medium Stiff to Stiff Gray LEAN CLAY w/Sand and Trace Gravel (CL)

23.5' Moist Stiff Gray LEAN CLAY w/Sand and Trace Gravel (CL)

25.0' Bottom of hole at 25.0 feet.

NOTES

LOGGED BY KKC

AT TIME OF DRILLING None

AT END OF DRILLING None

0hrs AFTER DRILLING Backfilled w/Cuttings and Bentonite Chips

GROUND WATER LEVELS:

CHECKED BY KCH

GROUND ELEVATION 707 ftRIG NO. D70DRILLING CONTRACTOR TTL Associates, Inc. TB CW

DRILLING METHOD 3-1/4 in. HSA

DATE STARTED 1/11/22 COMPLETED 1/11/22

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MATERIAL DESCRIPTION

BORING NUMBER B-4

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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TTL Associates 1915 N 12th St 43604 Telephone: 419-324-2222

2154202 leg Lovell FHCC SPS Addition

Notes:

1. Exploratory borings were drilled on January 11 and 12, 2022, using 3¼-inch inside diameter hollow-stem augers.

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 test borings were located in the field by TTL Associates, Inc. based on a proposed boring location plan in consultation with Alesia Architecture.

4. Ground surface elevations were estimated to the nearest foot based on topographic contours shown on the plan drawing provided by Calibre Engineering on February 14, 2022.

5. Unconfined Compressive Strength (tsf):

NP = Non-Plastic

PROJECT: Captain James A Lovell FHCC VA Medical Center, N. Chicago, IL TTL Associates, Inc. PROJECT NO: 2154202

TABULATION OF TEST DATA

Bo rin g N um be r

Sa m pl e

N um be r

Sa m pl e

In te rv al

D ep th (F ee t)

St an da rd

P en et ra tio n

(B lo w s pe r

Fo ot

N at ur al

M oi stu re

C on te nt o f D ry W ei gh t)

In -P la ce

D ry

D en sit y

(P ou nd s p er

C ub ic F oo t)

U nc on fin ed C om pr es siv e St re ng th (P ou nd s p er S qu ar e F oo t)

Particle Size Distribution (%)

Atterberg Limits (%)

U ni fie d

S oi lC la ss ifi ca tio n

G ra ve l

Co ar se S an d

M ed iu m

S an d

Fi ne

Sa nd

Si lt

Cl ay

Li qu id L im it

Pl as tic L im it

Pl as tic ity

In de x

*Unconfined compressive strength derived from a calibrated hand penetrometer 2154202 tbl Captain James A Lovell FHCC VA Medical Center N Chicago IL Sheet 1 of 3

B-1 SS-1 1.0-2.5 9 15.4 115.1 3,370

SS-2 3.5-5.0 19 14.2 *9,000

SS-3 6.0-7.5 25 16.6 114.5 5,120 4 0 5 8 21 62 24 10 14 CL

SS-4 8.5-10.0 11 16.1 121.0 4,570

SS-5 13.5-15.0 9 16.0 *4,000

SS-6 18.5-20.0 8 16.2 116.6 2,040

SS-7 23.5-25.0 14 11.4 124.1 4,360

B-2 SS-1 1.0-2.5 11 16.6 *7,000

SS-2 3.5-5.0 14 13.8 121.3 7,665

SS-3 6.0-7.5 22 15.2 *8,000

SS-4 8.5-10.0 18 15.4 *5,000

SS-5 13.5-15.0 12 15.3 124.2 2,505

SS-6 18.5-20.0 11 16.2 123.0 3,980

SS-7 23.5-25.0 17 14.6 122.6 6,200

PROJECT: Captain James A Lovell FHCC VA Medical Center, N. Chicago, IL TTL Associates, Inc. PROJECT NO: 2154202

Bo rin g N um be r

Sa m pl e

N um be r

Sa m pl e

In te rv al

D ep th (F ee t)

St an da rd

P en et ra tio n

(B lo w s pe r

Fo ot

N at ur al

M oi stu re

C on te nt o f D ry W ei gh t)

In -P la ce

D ry

D en sit y

(P ou nd s p er

C ub ic F oo t)

U nc on fin ed C om pr es siv e St re ng th (P ou nd s p er S qu ar e F oo t)

Particle Size Distribution (%)

Atterberg Limits (%)

U ni fie d

S oi lC la ss ifi ca tio n

G ra ve l

Co ar se S an d

M ed iu m

S an d

Fi ne

Sa nd

Si lt

Cl ay

Li qu id L im it

Pl as tic L im it

Pl as tic ity

In de x

*Unconfined compressive strength derived from a calibrated hand penetrometer 2154202 tbl Captain James A Lovell FHCC VA Medical Center N Chicago IL Sheet 2 of 3

B-3 SS-1 1.0-2.5 15 17.9 113.3 7,110 3 1 5 7 22 62 36 17 19 CL

SS-2 3.5-5.0 17 15.8 *8,000

SS-3 6.0-7.5 22 14.5 *9,000+

SS-4 8.5-10.0 15 14.1 122.3 7,575

SS-5 13.5-15.0 9 16.3 114.9 3,955

SS-6 18.5-20.0 9 15.7 120.2 3,170

SS-7 23.5-25.0 12 15.0 116.9 3,070

SS-8 28.5-30.0 18 15.7 *6,000

SS-9 33.5-35.0 19 15.6 *5,000

SS-10 38.5-40.0 17 15.8 *4,000

SS-11 43.5-45.0 19 21.4

SS-12 48.5-50.0 34 17.2 *9,000+

SS-13 53.5-55.0 20 17.5 115.4 4,585

SS-14 58.5-60.0 15 17.3 118.1 6,240

SS-15 63.5-65.0 29 19.1 *9,000+

SS-16 68.5-70.0 20 22.7 *5,000

SS-17 73.5-75.0 27 19.0 *7,500

PROJECT: Captain James A Lovell FHCC VA Medical Center, N. Chicago, IL TTL Associates, Inc. PROJECT NO: 2154202

Bo rin g N um be r

Sa m pl e

N um be r

Sa m pl e

In te rv al

D ep th (F ee t)

St an da rd

P en et ra tio n

(B lo w s pe r

Fo ot

N at ur al

M oi stu re

C on te nt o f D ry W ei gh t)

In -P la ce

D ry

D en sit y

(P ou nd s p er

C ub ic F oo t)

U nc on fin ed C om pr es siv e St re ng th (P ou nd s p er S qu ar e F oo t)

Particle Size Distribution (%)

Atterberg Limits (%)

U ni fie d

S oi lC la ss ifi ca tio n

G ra ve l

Co ar se S an d

M ed iu m

S an d

Fi ne

Sa nd

Si lt

Cl ay

Li qu id L im it

Pl as tic L im it

Pl as tic ity

In de x

*Unconfined compressive strength derived from a calibrated hand penetrometer 2154202 tbl Captain James A Lovell FHCC VA Medical Center N Chicago IL Sheet 3 of 3

B-3 SS-18 78.5-80.0 53 10.5

SS-19 83.5-85.0 34 13.1 125.3 5,685

SS-20 88.5-90.0 51 16.2 *9,000+

SS-21 93.5-95.0 21 20.9 115.4 3,855

SS-22 98.5-100.0 31 15.2

B-4 SS-1 1.0-2.5 5 16.0 100.6 2,000

SS-2 3.5-5.0 14 15.7 110.0 8,845

SS-3 6.0-7.5 27 15.8 *9,000+

SS-4 8.5-10.0 18 14.7 *9,000+

SS-5 13.5-15.0 14 15.7 119.4 3,625 0 1 5 10 20 64 27 13 14 CL

SS-6 18.5-20.0 8 16.6 118.3 3,310

SS-7 23.5-25.0 12 15.1 116.2 3,245

0.0010.010.1110100

PI Cc

CuLL PL

GRAIN SIZE DISTRIBUTION

COBBLES

GRAVEL

6.0

1.0

13.5

9.5

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

6.0

1.0

13.5

LEAN CLAY with SAND (CL)

LEAN CLAY with SAND (CL)

LEAN CLAY with SAND (CL)

Specimen Identification

Specimen Identification D100 D60 D30 D10 %Gravel

0.004

0.004

0.004

20.7

22.3

19.9

B-1

B-3

B-4 coarse

SILT OR CLAY

finemedium

%Sand %Silt %Clay

4.3

3.1

0.1

13.0

12.2

16.0

62.0

62.4

64.0

3 100

B-1

B-3

B-4

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

USCS Classification

CLIENT Alesia Architecture

PROJECT NUMBER 2154202

PROJECT NAME Project 556-402 - Expand SPS

PROJECT LOCATION North Chicago. IL

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TTL Associates, Inc.

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

Toledo, OH 43604-5305

T 419-324-2222 F 419-241-1808

Teamwork - Trust - Leadership Since 1927

November 18, 2022 TTL Project No. 2154202

Mr. Brad Schaap, PE, SE, LEED Fellow

Shaffer Stevens & Schaap, PC

1070 Howard Street

Omaha, Nebraska 68102

Project 556-402 – Expand SPS

Building 133CA – 1st Floor

Captain James A Lovell FHCC VA Medical Center

Dear Mr. Schaap:

This addendum letter report includes our recommendations for passive lateral earth pressures, coefficient of friction, bearing capacity with respect to wind or seismic loads, as well as water stop discussion based on an email provided by you to Mr. Curt Roupe of TTL on November 8, 2022, which included structural drawings SB1PB.2, SB501, and SB502, dated November 7, 2022.

Additionally, we have reviewed settlement with respect to the proposed duct bank foundation along column line 5. We have also reviewed the Earthwork Specification Section 31 20 00 sent via email from you to Mr. Roupe and Ms. Katherine Hennicken of TTL on November 16, 2022.

Lateral Earth Pressures

Passive earth pressures could be applied to structures that are constructed with concrete poured in intimate contact with firm native soils, or rigorously backfilled and compacted with engineered

“controlled” fill. In any case, a passive earth pressure (kp) of 3.0 would be applicable for the encountered cohesive soils below the floor slab elevation.

Seismic Lateral Earth Pressure Considerations

We have evaluated seismic-induced dynamic loading on the substructure in general accordance with the Mononobe-Okabe method, in conjunction with USACE Circular EC-1110-2-6058 regarding earthquake inertial forces on structures due to backfill. A design horizontal seismic coefficient of

0.102 was evaluated, based on the mapped spectral acceleration for a 1-second period earthquake

(0.102g). A positive value was assumed for a horizontal inertial force directed toward the wall. The design vertical seismic coefficient was estimated as 2/3 of the horizontal acceleration coefficient, with a positive value for a vertical inertial force directed upward.

Additional assumptions regarding the application of the Mononobe-Okabe method include the following:

Mr. Brad Schaap, PE, SE, LEED Fellow TTL Project No. 2154202

Shaffer Stevens & Schaap, PC Page 2

• The walls are considered to be…