Attachment 3 Project Manual Vol 1 V-PAR.pdf

Mike Monroney Aeronautical Center

Oklahoma City, OK

V-PAR

VTOL - Performance and Analysis Range

100% Type B Design Analysis

Contract No. 6973GH-21-D-00046

Work Order # 23-030509

September 18, 2025 October 15, 2025

100% IFC - Project Manual Volume 1

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V-PAR, VTOL – PERFORMANCE AND ANALYSIS RANGE BUILDING OK70448-013

SEALS PAGE 00 01 07 - 1

15 October 2025

10/15/2025

SEALS PAGE 00 01 07 - 2

TABLE OF CONTENTS 00 01 10 - 1

SECTION 00 01 10

TABLE OF CONTENTS

SECTIONS PAGES

VOLUME 1

COVER & TABLE OF CONTENTS

00 00 00 - TYPE B PROJECT MANUAL COVER VOLUME 1

00 01 07 - SEALS PAGE

00 01 10 - TABLE OF CONTENTS

DIVISION 00 — PROCUREMENT AND CONTRACTING REQUIREMENTS

00 31 32 - GEOTECHNICAL DATA

00 31 32.1 - FAA Vertiport Facility - ECS Project No. 2033

DIVISION 01 — GENERAL REQUIREMENTS

01 01 00 - SUMMARY OF WORK

01 01 90 - CONTRACT CONSIDERATIONS

01 02 80 - MODIFICATION PROCEDURES

01 03 00 - OPTIONS

01 03 90 - COORDINATION AND MEETINGS

01 30 00 - SUBMITTALS

01 40 00 - QUALITY REQUIREMENTS

01 40 00.01 - STATEMENT OF SPECIAL INSPECTIONS (SSI) -2018

01 43 39 - MOCKUPS

01 50 00 - CONSTRUCTION FACILITIES AND TEMPORARY CONTROLS

01 57 23 - STORMWATER POLLUTION PREVENTION

01 59 00 - FIELD OFFICES AND SHEDS

01 60 00 - MATERIAL AND EQUIPMENT

01 60 10 - SUBSTITUTION REQUEST FORM

01 65 00 - STARTING OF SYSTEMS

01 70 00 - CONTRACT CLOSEOUT

01 73 00 - OPERATION AND MAINTENANCE DATA

01 74 19 - CONSTRUCTION WASTE MANAGEMENT AND DISPOSAL PART 1 - GENERAL

01 77 00 - CLOSEOUT PROCEDURES

DIVISION 03 — CONCRETE

03 10 00 - CONCRETE FORMING AND ACCESSORIES

03 20 00 - CONCRETE REINFORCING

03 30 00 - CAST-IN-PLACE CONCRETE

03 35 11 - CONCRETE FLOOR FINISHES

DIVISION 05 — METALS

05 12 00 - STRUCTURAL STEEL FRAMING

05 21 00 - STEEL JOIST FRAMING

05 31 00 - STEEL DECKING

05 40 00 - COLD-FORMED METAL FRAMING

05 50 00 - METAL FABRICATIONS AND MISCELLANEOUS METAL

DIVISION 06 — WOOD, PLASTICS, AND COMPOSITES

06 10 00 - ROUGH CARPENTRY

06 16 00 - SHEATHING

06 41 00 - ARCHITECTURAL WOOD CASEWORK

06 64 00 - PLASTIC PANELING

TABLE OF CONTENTS 00 01 10 - 2

DIVISION 07 — THERMAL AND MOISTURE PROTECTION

07 21 00 - THERMAL INSULATION

07 21 19 - FOAMED-IN-PLACE INSULATION

07 27 26 - FLUID-APPLIED MEMBRANE AIR BARRIERS

07 42 13.13 - FORMED METAL WALL PANELS

07 54 23 - THERMOPLASTIC-POLYOLEFIN (TPO) ROOFING

07 62 00 - SHEET METAL FLASHING AND TRIM

07 71 00 - MANUFACTURED ROOF SPECIALTIES

07 92 00 - JOINT SEALANTS

DIVISION 08 — OPENINGS

08 11 13 - HOLLOW METAL DOORS AND FRAMES

08 41 13 - ALUMINUM-FRAMED ENTRANCES AND STOREFRONTS

08 71 00 - DOOR HARDWARE

08 80 00 - GLAZING

08 91 19 - FIXED LOUVERS

DIVISION 09 — FINISHES

09 22 16 - NON-STRUCTURAL METAL FRAMING

09 29 00 - GYPSUM BOARD

09 30 13 - CERAMIC TILING

09 51 13 - ACOUSTICAL PANEL CEILINGS

09 65 13 - RESILIENT BASE AND ACCESSORIES

09 65 19 - RESILIENT TILE FLOORING

09 91 13 - EXTERIOR PAINTING

09 91 23 - INTERIOR PAINTING

09 96 00 - HIGH-PERFORMANCE COATINGS

DIVISION 10 — SPECIALTIES

10 14 23 - ROOM-IDENTIFICATION PANEL SIGNAGE

10 14 23 -1 - FAA-MMAC DOOR SIGN CRITERIA

10 28 00 - TOILET ACCESSORIES

10 44 13 - FIRE PROTECTION CABINETS

10 44 16 - FIRE EXTINGUISHERS

10 73 16 - WEATHER SHELTER CANOPY

10 73 20 - CANTILEVER CANOPIES

DIVISION 11 — EQUIPMENT

11 30 13 - RESIDENTIAL APPLIANCES

DIVISION 12 — FURNISHINGS

12 24 13 - ROLLER WINDOW SHADES

12 36 61.10 - SOLID SURFACE COUNTERTOPS

DIVISION 22 — PLUMBING

22 05 00 - COMMON WORK RESULTS FOR PLUMBING

22 05 23 - GENERAL-DUTY VALVES FOR PLUMBING PIPING

22 05 29 - HANGERS AND SUPPORTS FOR PLUMBING PIPING AND EQUIPMENT

22 05 53 - IDENTIFICATION FOR PLUMBING PIPING AND EQUIPMENT

22 07 19 - PLUMBING PIPING INSULATION

22 11 16 - DOMESTIC WATER PIPING

22 11 19 - DOMESTIC WATER PIPING SPECIALTIES

22 13 16 - SANITARY WASTE AND VENT PIPING

22 13 19 - SANITARY WASTE PIPING SPECIALTIES

22 13 19.13 - SANITARY DRAINS

22 14 14 - STORM DRAINAGE PIPING

22 14 23 - STORM DRAINAGE PIPING SPECIALTIES

TABLE OF CONTENTS 00 01 10 - 3

22 33 00 - ELECTRIC, DOMESTIC-WATER HEATERS

22 42 00 - COMMERCIAL PLUMBING FIXTURES

DIVISION 23 — HEATING VENTILATING AND AIR CONDITIONING

23 05 00 - COMMON WORK RESULTS FOR HVAC

23 05 48.13 - VIBRATION CONTROLS FOR HVAC

23 05 53 - IDENTIFICATION FOR HVAC PIPING AND EQUIPMENT

23 05 93 - TESTING, ADJUSTING, AND BALANCING FOR HVAC

23 07 13 - DUCT INSULATION

23 07 19 - HVAC PIPING INSULATION

23 23 00 - REFRIGERANT PIPING

23 31 13 - METAL DUCTS

23 33 00 - AIR DUCT ACCESSORIES

23 33 46 - FLEXIBLE DUCTS

23 34 00 - HVAC FANS

23 37 13.13 - AIR DIFFUSERS

23 37 13.23 - REGISTERS AND GRILLES

23 81 26 - SPLIT-SYSTEM AIR-CONDITIONERS

23 81 26.01 - MINI-SPLIT AIR-CONDITIONERS

VOLUME 2

DIVISION 26 — ELECTRICAL

26 00 10 - SUPPLEMENTAL REQUIREMENTS FOR ELECTRICAL

26 05 13 - MEDIUM-VOLTAGE CABLES

26 05 19 - LOW-VOLTAGE ELECTRICAL POWER CONDUCTORS AND CABLES

26 05 26 - GROUNDING AND BONDING FOR ELECTRICAL SYSTEMS

26 05 29 - HANGERS AND SUPPORTS FOR ELECTRICAL SYSTEMS

26 05 33.13 - CONDUITS FOR ELECTRICAL SYSTEMS

26 05 33.16 - BOXES AND COVERS FOR ELECTRICAL SYSTEMS

26 05 43 - UNDERGROUND DUCTS AND RACEWAYS FOR ELECTRICAL SYSTEMS

26 05 44 - SLEEVES AND SLEEVE SEALS FOR ELECTRICAL RACEWAYS AND CABLING

26 05 53 - IDENTIFICATION FOR ELECTRICAL SYSTEMS

26 05 72 - OVERCURRENT PROTECTIVE DEVICE SHORT-CIRCUIT STUDY PART 1 - GENERAL

26 05 73 - OVERCURRENT PROTECTIVE DEVICE COORDINATION STUDY PART 1 - GENERAL

26 05 74 - OVERCURRENT PROTECTIVE DEVICE ARC-FLASH STUDY PART 1 - GENERAL

26 09 23 - LIGHTING CONTROL DEVICES

26 12 00 - VOLTAGE TRANSFORMERS

26 13 29 - VOLTAGE COMPARTMENTALIZED SWITCHGEAR

26 18 23 - MEDIUM VOLTAGE SURGE ARRESTERS

26 22 13 - LOW-VOLTAGE DISTRIBUTION TRANSFORMERS

26 24 16 - PANELBOARDS

26 27 13 - ELECTRIC METERS

26 27 26 - WIRING DEVICES

26 28 16 - ENCLOSED SWITCHES AND CIRCUIT BREAKERS

26 41 13 - LIGHTNING PROTECTION SYSTEMS

26 43 13 - SURGE PROTECTIVE DEVICES FOR LOW-VOLTAGE ELECTRICAL POWER CIRCUITS

26 50 00 - LIGHTING

DIVISION 27 — COMMUNICATIONS

27 00 00 - GENERAL PROVISION FOR TELECOMMUNICATIONS SPECIFICATIONS

CONSTRUCTION STANDARD

27 00 00.1 - TELECOMMUNICATIONS STANDARDS FOR THE MIKE MONRONEY AERONAUTICAL

CENTER

27 10 00 - STRUCTURED CABLING

TABLE OF CONTENTS 00 01 10 - 4

DIVISION 28 — ELECTRONIC SAFETY AND SECURITY

28 14 00 - ACCESS CONTROL SYSTEM HARDWARE

28 31 10 - FIRE ALARM SYSTEM, ADDRESSABLE, TONE TYPE

DIVISION 31 — EARTHWORK

200 - EARTHWORK (COKC)

300 - SURFACES (COKC)

31 31 16 - TERMITE CONTROL

400 - CONCRETE (COKC)

500 - WATER (COKC)

600 - SANITARY (COKC)

800 - INCIDENTAL CONSTRUCTION (COKC)

900 - MATERIALS (COKC)

C-102 TEMPORARY AIR AND WATER POLLUTION, SOIL EROSION, AND SILTRATION CONTROL

D-701 PIPE FOR STORM DRAINS AND CULVERTS

D-751 MANHOLES, CATCH BASINS, INLETS AND INSPECTION HOLES

L-107 AIRPORT WIND CONES

L-108 UNDERGROUND POWER CABLE FOR AIRPORTS

L-110 AIRPORT UNDERGROUND ELECTRICAL DUCT BANKS AND CONDUITS

L-115 ELECTRICAL JUNCTION STRUCTURES

L-125 INSTALLATION OF AIRPORT LIGHTING SYSTEMS

P-152 EXCAVATION, SUBGRADE, AND EMBANKMENT

P-156 CEMENT TREATED SUBGRADE

P-209 CRUSHED AGGREGATE BASE COURSE

P-501 CEMENT CONCRETE PAVEMENT

P-605 JOINT SEALANTS FOR PAVEMENTS

P-610 CONCRETE FOR MISCELLANEOUS STRUCTURES

P-620 RUNWAY AND TAXIWAY MARKING

T-904 SODDING

T-905 TOPSOIL

DIVISION 33 — UTILITIES

33 71 19 - ELECTRICAL UNDERGROUND DUCTS, DUCTBANKS, AND MANHOLES

GEOTECHNICAL DATA 00 31 32 - 1

DOCUMENT 00 31 32 - GEOTECHNICAL DATA

PART 1 - GENERAL

1.1 GEOTECHNICAL DATA

A. This Document, with its referenced attachments, is part of the Procurement and Contracting Requirements for the Project. They provide Owner's information for Bidders' convenience and are intended to supplement rather than serve in lieu of Bidders' own investigations. They are made available for Bidders' convenience and information. This Document and its attachments are not part of the Contract Documents.

B. Because subsurface conditions indicated by the soil borings are a sampling in relation to the entire construction area, and for other reasons, Owner, Architect, Architect's consultants, and the firm reporting the subsurface conditions do not warranty the conditions below the depths of the borings or that the strata logged from the borings are necessarily typical of the entire site.

Any party using the information described in the soil borings and geotechnical report accepts full responsibility for its use.

C. A Geotechnical Investigation Report for Project, prepared by ECS Southwest, LLP, dated February 21, 2025, is available for viewing as appended to this Project Manual.

1. The opinions expressed in this report are those of a geotechnical engineer and represent interpretations of subsoil conditions, tests, and results of analyses conducted by a geotechnical engineer. Owner is not responsible for interpretations or conclusions drawn from the data.

2. Any party using information described in the geotechnical report will make additional test borings and conduct other exploratory operations that may be required to determine the character of subsurface materials that may be encountered at no additional cost to the Owner.

PART 2 - PRODUCTS (NOT USED)

PART 3 - EXECUTION (NOT USED)

END OF DOCUMENT 00 31 32

ECS Southwest, LLP Geotechnical Engineering Report FAA Vertiport Facility

McLucas Steet and Halaby Drive Oklahoma City, Oklahoma

ECS Project Number 58:2033

February 21, 2025

FAA Vertiport Facility February 21, 2025 ECS Project No. 58:2033 Page i

TABLE OF CONTENTS

EXECUTIVE SUMMARY

1.0 INTRODUCTION

2.0 PROJECT INFORMATION

2.1 Project Location/Current Site Use

2.2 Proposed Construction

3.0 FIELD EXPLORATION AND LABORATORY TESTING

3.1 Subsurface Characterization

3.2 Groundwater Observations

3.3 Laboratory Testing

4.0 DESIGN RECOMMENDATIONS

4.1 Potential Vertical Movements

4.2 Subgrade Improvements

4.3 Shallow Foundations

4.4 Drilled Piers

4.4.1 Lateral Considerations

4.4.2 Uplift Considerations

4.5 Building Slab

4.5.1 Structurally Suspended Slab

4.5.1 Slab on Grade

4.6 Building Perimeter Conditions

4.7 Seismic Design Considerations

4.8 Pavements

4.9 Site Retaining Walls

4.10 Corrosion Potential

5.0 SITE CONSTRUCTION RECOMMENDATIONS

5.1 Subgrade Preparation

5.1.1 Stripping and Grubbing

5.1.2 Proofrolling

5.2 Earthwork Operations

5.2.1 Fill Placement

5.2.2 Earthwork Testing

5.3 Material Specifications

5.3.1 Select Fill

5.3.2 Moisture Conditioning

5.3.3 Lime Stabilized On Site Clay

5.4 Foundation and Slab Observations

5.5 Utility Installations

6.0 CLOSING

ECS Project No. 58:2033 Page ii

APPENDICES

Appendix A – Drawings & Reports

• Site Location Diagram

• Boring Location Diagram

• Generalized Subsurface Soil Profile A-A’

• Clay Plug Detail at Trench

Appendix B – Field Operations

• Reference Notes for Boring Logs

• Subsurface Exploration Procedures: Standard Penetration Testing (SPT)

• Boring Logs B-01 to B-08

Appendix C – Laboratory Testing

• Laboratory Testing Summary

• Standard Proctor Curve Test Reports

• California Bearing Ratio (CBR) Test Reports

ECS Project No. 58:2033 Page 1

EXECUTIVE SUMMARY

This Executive Summary is intended as a very brief overview of the primary geotechnical conditions that are expected to affect design and construction. The following summarizes the main findings of the exploration, particularly those that may have a cost impact on the planned development.

Further, our principal foundation recommendations are summarized. Information gleaned from the executive summary should not be utilized in lieu of reading the entire geotechnical report.

• The planned project consists of the construction of an approximately 5,625 square feet, one-vehicular hangar consisting of structural steel or cast-in-place reinforced concrete construction with an approximately 1,600 square feet, single-story, administration/restroom space consisting of light frame construction and associated ground-based landing pad/apron and parking/drive areas. We have assumed the structures will be entirely above grade. We understand anticipated maximum structural loads are to be column loading of 200 kips and have assumed maximum wall loads of 6 kips/foot. We have assumed the structure will have a finished floor elevation at or near the existing grade.

• The planned structures may be supported on a shallow foundation system consisting of spread footings with conventional slab on grade, provided the subgrade is improved and prepared as outlined in this report. Should improving the subgrade in order to use conventional spread footings and slab on grade be cost prohibitive, a reinforced slab with grade beams (monolithic slab/BRAB) or post-tensioned slab on grade may be used on the existing soils. As an alternative, a drilled pier and grade beam foundation system could also be used. Drilled piers should extend into the underlying weathered shale and can be used with a conventional slab on grade, provided the subgrade is improved as recommended.

Alternatively, drilled piers could be used with a structurally suspended floor slab in which case subgrade improvements are not required.

• The soils encountered at the site are highly active. Therefore, subgrade improvements will be necessary to reduce the potential for vertical movements. Specific details on addressing these highly expansive clay soils are presented in the body of the report.

• Pavements should be supported directly on stabilized subgrades or a layer of aggregate base upon subgrades that are evaluated and prepared as outlined in this report.

• It is recommended that ECS conduct a geotechnical review of the project plans (prior to issuance for construction) to check to see that ECS’ geotechnical recommendations have been properly interpreted and implemented.

• To prevent misinterpretation of ECS recommendations, ECS should be retained to perform quality control testing and documentation during construction of the earthwork and foundations for the project.

ECS Project No. 58:2033 Page 2

1.0 INTRODUCTION

The purpose of this study was to provide geotechnical information for the design and construction of the foundations, floor slabs, retaining walls, and pavements for the planned FAA Vertiport Facility project located near McLucas Street and Halaby Drive within the Mike Monroney Aeronautical Center campus in Oklahoma City, Oklahoma. The recommendations developed for this report are based on project information provided by the client.

Our services were provided in accordance with our Proposal No. 58:3505-GP Revised, dated December 18, 2024, and authorized by the client by providing the subconsultant task order OK70448011-0820 on January 3, 2025

This report contains the procedures and results of our subsurface exploration and laboratory testing programs, review of existing site conditions, engineering analyses, and recommendations for the design and construction of the project.

The report includes the following items.

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

• A review of surface topographical features and site conditions.

• A review of area and site geologic conditions.

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

• A final copy of our soil test borings.

• Recommendations for site preparation and construction of compacted fills, including an evaluation of on-site soils for use as compacted fills.

• Recommended foundation types.

• General recommendations for pavement design.

• General recommendations for retaining wall design.

2.0 PROJECT INFORMATION

2.1 PROJECT LOCATION/CURRENT SITE USE

The project is located along the westbound side of McLucas Street and is approximately 1,000 feet west of Halaby Drive within the Mike Monroney Aeronautical Center campus in Oklahoma City, Oklahoma. The location is depicted in Figure 2.1.1 as shown below.

ECS Project No. 58:2033 Page 3

Figure 2.1.1. Site Location

ECS reviewed aerial photographs of the subject site dated 1990 to 2024. Since April 1990, the site has been an undeveloped, grassed property. At some time between February 1995 and October 1998, it appears McLucas Street and Halaby Drive were constructed in areas south and east of the site. Since that time, the site has remained relatively unchanged.

Currently the site is an undeveloped, grassed property. The topography of the site generally slopes down from southwest to northeast with maximum and minimum boring elevations of EL 1300 and EL 1294, respectively. The ground surface elevations noted in this report were obtained from the USGS National Map provided and have been rounded to the nearest foot.

2.2 PROPOSED CONSTRUCTION

The following information explains our understanding of the planned development including the proposed building and related infrastructure.

SUBJECT DESIGN INFORMATION / ASSUMPTIONS

Building Footprint Hangar: approx. 5,625 square feet

Administration/Restroom: approx. 1,600 square feet # of Stories Single-story above grade Usage Aviation/maintenance Framing Hangar: structural steel or cast-in-place reinforced concrete

Administration/Restroom: light framing Column Loads 200 kips (Full Dead and Live Load) maximum Wall Loads (assumed) 6 kips per linear foot (klf) maximum

ECS Project No. 58:2033 Page 4

SUBJECT DESIGN INFORMATION / ASSUMPTIONS

Lowest Finish Floor Elevation Unknown, assumed no more than 2 feet below or above existing grades

We also understand that associated parking/drive areas will be constructed. If ECS’ understanding of the project is not correct, especially if the structural loads are different, please contact ECS so that we may review these changes and revise our recommendations, as appropriate.

3.0 FIELD EXPLORATION AND LABORATORY TESTING

Our exploration procedures are explained in greater detail in Appendix B including the insert titled Subsurface Exploration Procedures. Our scope of work included drilling eight (8) borings. The boring locations were selected by ECS based on the site plan provided by the client and identified in the field by the drilling crew using boring GPS coordinates generated by ECS. Approximate as-drilled boring locations are shown on the Boring Location Diagram in Appendix A.

3.1 SUBSURFACE CHARACTERIZATION

The subsurface conditions encountered were generally consistent with published geological mapping. The following sections provide generalized characterizations of the soil strata encountered during our subsurface exploration. For specific subsurface information refer to the boring logs in Appendix B.

Approximate Depth of Bottom of Strata

Below Grade Elevation(1) (ft) Stratum Material Description Consistency /

Density

6 inches --- Cover Topsoil --

13 to 14 feet Elevation 1285 to 1282 I

(CL) LEAN CLAY, LEAN CLAY WITH

SAND, and (CH) FAT CLAY, various shades of red, brown, and gray Soft to Very Hard

19 feet(2) Elevation 1280 to 1277 II(3) (WR) WEATHERED SHALE, various shades of red Very Hard

Notes:

(1) Elevations are approximate.

(2) Depth to deepest boring termination depth.

(3) Stratum II was encountered in the building borings only.

Please refer to the attached boring logs and laboratory data summary for this field exploration for a more detailed description of the subsurface conditions encountered in the borings as the stratification descriptions above are generalized for presentation purposes.

3.2 GROUNDWATER OBSERVATIONS

Water levels were measured in our boring logs in Appendix B. Groundwater was not observed in the borings at the time of our exploration and is indicated on the boring logs as “dry”.

Variations in the long-term water table may occur as a result of changes in precipitation, evaporation, surface water runoff, construction activities, and other factors.

ECS Project No. 58:2033 Page 5

3.3 LABORATORY TESTING

The laboratory testing consisted of selected tests performed on samples obtained during our field exploration operations. Classification and index property tests were performed on representative soil samples. Testing performed include moisture content, Atterberg Limits, percent passing the No. 200 sieve, Standard Proctor, California Bearing Ratio (CBR), and corrosion testing which includes pH, resistivity, and total soluble sulfate.

Samples were visually classified based on texture and plasticity in accordance with ASTM D2488 Standard Practice for Description and Identification of Soils (Visual-Manual Procedures) and including USCS classification symbols, and ASTM D2487 Standard Practice for Classification for Engineering Purposes (Unified Soil Classification System (USCS). After classification, the samples were grouped in the major zones noted on the boring logs in Appendix B. The group symbols for each soil type are indicated in parentheses along with the soil descriptions. The stratification lines between strata on the logs are approximate; in situ, the transitions may be gradual.

4.0 DESIGN RECOMMENDATIONS

4.1 POTENTIAL VERTICAL MOVEMENTS

The intent of recommendations contained in this report are provided in order to reduce the potential risk associated with the shrink/swell tendencies of the on-site expansive soil, should a conventional shallow footing foundation and slab on grade be used.

The majority of clay soils encountered in the borings have a high expansion potential. Based on our Atterberg limits laboratory test results and experience with similar soils, we estimate potential vertical soil movements (PVM) of the highly expansive soils encountered in the borings of up to about 2 ½ inches, based on dry conditions. These potential movements reflect moisture changes in the soil that can occur over the life of the structure and after construction is complete. The actual movements could be greater if poor drainage, ponded water, and/or other unusual sources of moisture are allowed to saturate the soils beneath the structure after construction.

4.2 SUBGRADE IMPROVEMENTS

In order to reduce the risk associated with future movements due to expansion potential, we recommend the following general building pad subgrade improvements to reduce the PVM to approximately 1 inch. Please note, these recommendations are the minimum requirements to reduce potential movements due to expansion potential, should conventional spread footings and slab on grade be used. If a monolithic slab/BRAB slab or post-tensioned slab be used to support the structure, subgrade improvements are not required as those systems are design to withstand the potential vertical movements. Alternatively, drilled piers could be used with a structurally suspended floor slab in which case subgrade improvements are not required.

ECS Project No. 58:2033 Page 6

Options Depth of Select Fill (feet)

Depth of Moisture Conditioning (feet)

Total Depth of Improved Zone (feet)

Estimated

PVM

(inch)

Option 1 3 --- 3 1

Option 2 2 2 4 1

Option 3 --- 5 5 1

The subgrade improvements should extend at least 5 feet beyond the edge of the building pads and include any flatwork sensitive to movements such as sidewalks or pavements. Exterior perimeter footing/grade beam backfill should consist of moisture conditioned clay soil. Please refer to the “Material Specifications” section of this report for more details.

These design parameters assume that positive drainage will be provided away from the structures and with moderate irrigation of surrounding lawn and planter areas with no excessive wetting or drying of soils adjacent to the foundations. Greater potential movements could occur with extreme wetting or drying of the soils due to ponding of water, plumbing leaks or lack of irrigation. Recommendations for earthwork operations are found in the “Site Construction Recommendations” portion of this report.

4.3 SHALLOW FOUNDATIONS

Provided the subgrades are improved and structural fills are prepared as recommended in this report, the proposed structures can be supported by conventional shallow foundations including column footings and continuous wall footings. We recommend the foundation design use the following parameters:

Design Parameter Column Footing Wall Footing

Net Allowable Bearing Pressure(1) 3,000 psf 3,000 psf

Bearing Soil Material Improved Subgrade Improved Subgrade

Minimum Width 24 inches 18 inches

Minimum Footing/Grade Beam Embedment Depth (below slab or finished grade) (2) 24 inches 24 inches

Estimated Total Settlement (3) Less than 1- inch Less than 1- inch

Estimated Differential Settlement (4)

Less than ¾ inches between columns

Less than ¾ inches per 30 linear feet

Notes:

(1) Net allowable bearing pressure is the applied pressure in excess of the surrounding overburden soils above the base of the foundation.

(2) For bearing considerations and frost penetration requirements.

(3) Based on our assumed structural loads. If final loads are different, ECS must be contacted to update foundation recommendations and settlement calculations.

(4) Based on maximum loads and variability in borings. Differential settlement can be re-evaluated once the foundation plans are more complete.

ECS Project No. 58:2033 Page 7

Monolithic Slab/BRAB: Should improving the subgrade in order to use conventional shallow foundations and slab on grade be cost prohibitive, foundations consisting of a reinforced slab with grade beams (monolithic slab/BRAB) under load bearing walls could also be used to support the proposed structures.

The reinforced slab may be designed using a soil modulus of subgrade reaction of 125 pci and the grade beams or spread footings may be designed for a net allowable soil bearing pressure of 3,000 psf bearing on newly placed and compacted select fill or natural soils that were encountered in the borings.

If a monolithic slab is used this system may be designed with conventional reinforcing. The slab should be designed in accordance with WRI/CRSI “Design Slab-On-Ground Foundations”. The structure can be supported on a monolithic/waffle slab and grade beam foundation system designed in accordance with the following information:

Design Parameter BRAB/WRI Slab

Allowable Bearing Pressure 3,000 psf

Design PI 39

Climatic Rating (Cw) 20

Soil-Climate Support Index (1-C) 0.25

Post-Tensioned Slab: In lieu of a BRAB/WRI slab, a post-tensioned slab on grade could also be used on the existing soils without subgrade improvement. The following design parameters are recommended for the Post-Tensioning Institute's slab-on-grade design method (3rd Edition) should that method be chosen:

Center Lift Edge Lift em (feet) Ym (inches) em (feet) Ym (inches)

9.0 1.5 5.0 2.0

Potential Undercuts: Due to the presence of relatively soft soils, DCP testing of the bearing soils by ECS representatives should be incorporated during construction to verify their suitability for supporting shallow foundations. If soft or inadequate soils are observed at the footing bearing elevations, these soils should be undercut and removed. Any undercut should be backfilled with lean concrete (f’c ≥ 1,000 psi at 28 days) up to the original design bottom of footing elevation; the original footing shall be constructed on top of the hardened lean concrete.

4.4 DRILLED PIERS

A drilled straight shaft pier and grade beam system could also be used to support the structures.

We recommend the drilled pier design use the following parameters:

ECS Project No. 58:2033 Page 8

Design Parameter Drilled Pier

Bearing Material(1) (WR) WEATHERED SHALE that was encountered in the building borings at depths of approximately 13 to 14 feet below existing site grades

Minimum Embedment Depth 2 feet into approved bearing material

Net Allowable End Bearing Pressure(1) 30 ksf

Net Allowable Skin Friction Resistance(2) 2.5 ksf

Net Allowable Tension/Uplift Resistance 1 ksf

Minimum Pier Diameter(3) 18 inches

Minimum Pier Spacing between New and Existing Piers (center to center)

100% Capacity with min Center to Center Spacing Ratio of 3 pier diameters linearly reduced to 50%

Capacity at 2 pier diameters

Minimum Pier Length (from top of pier) Three times the pier diameter

Minimum Grade Beam Depth(4) 24 inches below finish grade

Estimated Total Settlement <1 inch

Estimated Differential Settlement 0.5 inches between piers

Notes:

(1) Drilled pier installation should be observed by ECS to verify that proper bearing material is encountered and minimum embedment is achieved.

(2) Skin friction resistance should be used for the portion of the pier that penetrates the approved bearing material only.

(3) Assumes the pier is designed with adequate reinforcing steel.

(4) Grade beams and piers should be structurally connected.

(5) Column loads should be supported by the drilled piers while wall loads can be carried by the grade beams.

Installation: The use of temporary casing is not expected to be necessary; however, this is contingent upon the groundwater conditions at the specific locations of the structures at the time of construction. This office should be contacted for additional recommendations if seepage cannot be controlled by conventional means (i.e. placement of concrete soon after the excavation is complete, use of sump pumps, use of temporary steel casing, etc.).

Installation (drill and final concrete placement) of individual shafts should be completed in one day.

This time limit does not only have design implications (reduction of side friction, excessive settlement due to the softening and saturation of bearing materials) but also has practical implications such as losing steel casing in the ground due to excessive soil squeeze and set up, losing shaft integrity due to instabilities or continuous seepage as well as loss of side friction resistance.

The concrete should have a slump between 5 and 7 inches and should be placed in a manner that prevents it from striking the reinforcing steel and sides of the excavation (such as using a tremie).

We recommend that all drilled shafts be observed by ECS personnel, to verify proper shaft installation. The concrete in the upper five feet of the shaft should be mechanically consolidated.

4.4.1 Lateral Considerations

Drilled Shafts may be subject to lateral loads. For the lateral design consideration of the drilled shafts bearing in weathered bedrock, we are providing the following information that can be used in ENSOFT’s LPILE 2013 computer program:

ECS Project No. 58:2033 Page 9

LPILE Design Parameters - Soil

LPILE Design Parameters - Rock

Soil Description LPILE Material

Description

Unit Weight

(pcf)

Uniaxial Compressive Strength, (psi)

Elastic Modulus, krm (psi)

RQD

E50

Weathered Shale

Weak Rock (Reese)

130 300 50,000 50 0.0005

4.4.2 Uplift Considerations

We recommend using an uplift of 1,000 psf over the shaft perimeter to a depth of 8 feet. This uplift may be reduced to 500 psf at depths where moisture conditioned soils are used and may be considered negligible at depths where select fill soils are used.

The drilled shafts should contain sufficient reinforcing steel throughout the shaft length (top of shaft to bottom of shaft) to resist uplift (tensile) forces due to post-construction heave of the clay soils. The magnitude of uplift is difficult to estimate and will vary with the in-situ moisture contents at the time of construction.

Widening the upper portion of the pier (or pier cap) will create the potential for high uplift pressures from the underlying clay soils, regardless of the subgrade improvement selected. This condition should be avoided, and if required, the piers should be designed for an uplift of 6 ksf acting on the entire surface of the bottom of the widened portion of the pier (or pier cap). Alternatively, the pier (or pier cap) may be underlain by nominal 6-inch void (PVR of 1 inch or less) or 12 inches of low volume change material or select fill.

4.5 BUILDING SLAB

Since the potential vertical movements (PVM) of the existing soil may be beyond normal design tolerances for interior slabs, the most positive method to reduce movements of slabs to very low levels would be to structurally suspend these slabs above the active clays. We are providing both a suspended slab supported by the drilled pier foundations and a slab on grade.

4.5.1 Structurally Suspended Slab

In lieu of providing any subgrade improvements, we believe that the lowest risk option of future movements and their impact on the building would be to structurally suspend the slab either using

Soil Description LPILE Material Desciption

Unit Weight, (pcf)

Undrained Shear strength, (psf)

Friction Angle, (degrees)

Subgrade Modulus, (pci) E50

Upper 3 feet Ignore Ignore Ignore Ignore - Ignore

Engineered Fill Sand (Reese) 120 - 33 90 -

Moisture Conditioned Soil Soft Clay 120 500 - - 0.01

Existing Clays Stiff Clay without Free Water 120 2,000 - - 0.05

ECS Project No. 58:2033 Page 10 a crawl space or void cartons. If void cartons are used, they should be at least 24 inches beneath the slab and all grade beams.

If a crawl space is provided below the floor slabs, adequate ventilation should also be provided.

Additionally, if a crawl space will be primarily below the level of existing grade, a vertical moisture barrier should be considered around the perimeter of the structures. Adequate drainage should be provided should standing water infiltrate underneath the slabs.

The ground surface beneath suspended floors should be shaped and drained to prevent the ponding of water. A permanent sump pit should be considered.

4.5.1 Slab on Grade

A conventional slab on grade may be used provided it is supported on subgrades improved as presented in this report.

The following graphic depicts our soil-supported slab recommendations:

1.

2.

3.

Concrete Slab Thickness: 4 inches minimum Concrete Slab Strength: 3,000 psi minimum Drainage Layer Thickness: 4 inches minimum

4. Drainage Layer Material: GRAVEL (GP, GW)

5. Subgrade compacted per the earthwork recommendations provided.

Subgrade Modulus: Provided subgrades are improved and prepared as discussed herein, the slab may be designed assuming a modulus of subgrade reaction, k1 of 125 pci (lbs/cu. inch).

Vapor Retarder: Before the placement of concrete, a vapor retarder may be placed on top of the granular drainage layer to provide additional protection against moisture penetration through the floor slab. When a vapor retarder is used, special attention should be given to surface curing of the slab to reduce the potential for uneven drying, curling and/or cracking of the slab. Depending on proposed flooring material types, the structural engineer and/or the architect may choose to eliminate the vapor retarder.

Slab Isolation: Soil-supported slabs should be isolated from the foundations and foundation-supported elements of the structure so that differential movement between the foundations and slab will not induce excessive shear and bending stresses in the floor slab. Where the structural configuration prevents the use of a free-floating slab such as in a drop-down footing/monolithic slab configuration, the slab should be designed with suitable reinforcement and load transfer devices to reduce the risk of overstressing of the slab.

Concrete Slab

Improved Subgrade (as recommended)

Vapor Retarder

Granular Base Layer

ECS Project No. 58:2033 Page 11

4.6 BUILDING PERIMETER CONDITIONS

Soils placed along the exterior of the foundations should consist of fine-grained soils encountered on site, placed and compacted in accordance with the “Fill Placement” section of this report. The purpose of this clay backfill is to reduce the opportunity for surface or subsurface water infiltration beneath the structure. Additionally, where lateral penetrations (for utilities) into or below the structure occur, a clay plug (or suitable synthetic alternative) should be placed at the building line to reduce the opportunity for infiltrating water, regardless of the backfill material. A clay plug detail is included in Appendix A.

Positive drainage away from the structure should also be provided. Additionally, irrigation of lawn and landscaped areas should be moderate, with no excessive wetting or drying of soils around the perimeter of the structures allowed. Trees and bushes/shrubs planted near the perimeter of the structures can withdraw large amounts of water from the soils and should be planted at least their anticipated mature height away from the building.

Where flatwork is placed against or near the structure, a positive seal must be installed and adequately maintained to limit water intrusion. Down spouts and gutters should be used to collect and distribute water at least 10 feet away from the structure.

Routine maintenance of the building perimeter condition is necessary so that the recommendations contained in this report are followed and maintained. Greater potential vertical movements could occur with extreme wetting or drying of the soils due to poor drainage, ponding of water, plumbing leaks, lack of irrigation, and/or lack of routine maintenance, etc.

4.7 SEISMIC DESIGN CONSIDERATIONS

Seismic Site Classification: The International Building Code (IBC) 2018 requires site classification for seismic design based on ASCE 7-16 and the upper 100 feet of a soil profile. At least two methods are utilized in classifying sites, namely the shear wave velocity (vs) method and the Standard Penetration Resistance (N-value) method. The Standard Penetration Resistance (N-value) method was used in classifying this site.

SEISMIC SITE CLASSIFICATION

Site

Class Soil Profile Name Shear Wave Velocity, Vs, (ft./s)

N value (bpf)

A Hard Rock Vs > 5,000 fps N/A

B Rock 2,500 < Vs ≤ 5,000 fps N/A

C Very dense soil and soft rock 1,200 < Vs ≤ 2,500 fps >50

D Stiff Soil Profile 600 ≤ Vs ≤ 1,200 fps 15 to 60

E Soft Soil Profile Vs < 600 fps <15

Based upon our interpretation of the subsurface conditions, the appropriate Seismic Site Classification is “C” as shown in the preceding table.

Ground Motion Parameters: In addition to the seismic site classification, ECS has determined the design spectral response acceleration parameters following the IBC/ASCE 7-16 methodology. The Mapped Reponses were estimated from the U.S. Seismic Design Maps website

ECS Project No. 58:2033 Page 12 https://seismicmaps.org/. The design responses for the short (0.2 sec, SDS) and 1-second period (SD1) are noted in bold at the far right end of the following table.

GROUND MOTION PARAMETERS [IBC 2015/2018 Method]

Period (sec)

Mapped Spectral Response

Accelerations (g)

Values of Site Coefficient for Site Class

Maximum Spectral Response Acceleration

Adjusted for Site Class (g)

Design Spectral Response

Acceleration (g)

Reference Figures 1613.3.1

(1) & (2)

Tables 1613.3.3

(1) & (2)

Eqs. 16-37 & 16-38

Eqs. 16-39 & 16-40

0.2 SS 0.342 Fa 1.3 SMS=FaSs 0.445 SDS=2/3

SMS

0.297

1.0 S1 0.084 Fv 1.5 SM1=FvS1 0.126 SD1=2/3

SM1

0.084

The Site Class definition should not be confused with the Seismic Design Category designation which the Structural Engineer typically assesses. If a higher site classification is beneficial to the project, we can provide additional testing methods that may yield more favorable results.

4.8 PAVEMENTS

Subgrade Characteristics: Based on the results of our borings, it appears that the pavement subgrades will consist of existing moderate to high plasticity soils. Based on the results of our laboratory tests and our experience with similar soils, a CBR value of 3 is recommended for this project site. The subgrade should be prepared in accordance with the recommendations in the Site Construction Recommendations section of this report.

We were not provided traffic loading information so we have assumed heavy duty pavements will experience a maximum traffic loading of 300,000 ESALs.

The preliminary pavement sections below are guidelines that may or may not comply with local jurisdictional minimums.

PROPOSED PAVEMENT SECTIONS

FLEXIBLE PAVEMENT RIGID PAVEMENT

MATERIAL Heavy Duty Light Duty Heavy Duty Light Duty Portland Cement Concrete(1) - - 6 in. 5 in.

Asphaltic Concrete Surface Course 2 in. 2 in. - -

Asphaltic Concrete Binder Course(2) 4 ½ in. 3 in. - -

Stabilized Subgrades(3,4) 8 in. 8 in. 8 in. 8 in.

Notes:

(1) Due to the excessive surface wear and subsequent deterioration of asphalt pavement caused by turning truck traffic, we recommend that any areas where trucks will be turning or backing up be constructed of Portland cement concrete only.

(2) ODOT Type A aggregate base material may be substituted for the asphalt binder using a substitute ratio of three inches of aggregate base for each inch of asphalt binder.

(3) Based on experience with similar soils, we estimate 5% to 6% Hydrated Lime will be required to stabilize the near surface soils at this site. The final amount and type of stabilizing agent https://seismicmaps.org/

ECS Project No. 58:2033 Page 13 should be determined at the time of construction based on the type(s) of material(s) at final grade.

(4) In lieu of stabilized subgrades, 8 inches of ODOT Type A aggregate base material may be used.

ECS should be allowed to review these recommendations and make appropriate revisions based upon the formulation of the final traffic design criteria for the project. It is important to note that the design sections do not account for construction traffic loading. It should also be noted that these design recommendations may not satisfy the local jurisdictional traffic guidelines. Any roadways constructed for public use and to be dedicated to the local or state jurisdiction for repair and maintenance must be designed in accordance with those jurisdictional requirements.

In general, heavy-duty sections are areas that will be subjected to trucks, buses, or other similar vehicles including main drive lanes of the development. Light duty sections are appropriate for vehicular traffic and parking areas.

An important consideration with the design and construction of pavements is surface and subsurface drainage. Where standing water develops, either on the pavement surface or within the base course layer, softening of the subgrade and other problems related to the deterioration of the pavement can be expected. Furthermore, good drainage should reduce the possibility of the subgrade materials becoming saturated during the normal service period of the pavement.

Large, front loading trash dumpsters frequently impose concentrated front wheel loads on pavements during loading. This type of loading typically results in rutting of asphalt pavement and ultimately pavement failures. For preliminary design purposes, we recommend that the pavement in trash pickup areas consist of an 8-inch-thick Portland Cement Concrete (PCC) pavement section.

Appropriate jointing should also be incorporated into the design of the PCC pavement. When traffic loading becomes available ECS, or the Civil Engineer can design the pavements.

Pavements should be specified, constructed and tested to meet the ODOT Standard Specifications for Highway Construction and the following requirements:

1. Reinforcing steel may consist of #3 reinforcing steel bars placed at 18 inches on center each way.

2. Hot Mix Asphaltic Concrete: In accordance with Oklahoma Department of

Transportation (ODOT) Standard Specifications.

3. Portland Cement Concrete: Minimum compressive strength of 3,500 psi (28 Days).

Concrete should be designed with 3 to 6 percent entrained air.

4. Crushed Limestone Base Material: ODOT Type A Aggregate Base. The material should be compacted to a minimum 95 percent of Standard Proctor maximum dry density (ASTM D 698) and within three percentage points of the material's optimum moisture.

4.9 SITE RETAINING WALLS

Unlike below grade walls, site retaining walls are free to rotate at the top (not restrained). For these walls the "Active" (ka) soil condition should be used along with a triangular distribution of earth pressures. In addition, site retaining walls should be designed to withstand lateral earth pressures exerted by the backfill and any surcharge loads within the “Critical Soil Zone”. The Critical

ECS Project No. 58:2033 Page 14

Zone is defined as the area between the back of the retaining wall footing and an imaginary line projected upward and rearward at a 45-degree angle (see figure below).

The lateral earth pressures developed behind site retaining walls are a function of the backfill soil type, backfill slope angle, and any surcharge loads. For the design of site retaining walls, we recommend the soil parameters provided below.

RETAINING WALL BACKFILL IN THE CRITICAL SOIL ZONE

Soil Parameter Estimated Value

Soil Classification LEAN CLAY (CL) or more granular

Fines Content (passing #200 Sieve) Max. 90%

Coefficient of Active Earth Pressure (Ka) 0.42 Retained Soil Moist Unit Weight (γ) 120 pcf Cohesion (C) 100 psf

Angle of Internal Friction (φ) 24°

Active Equivalent Fluid Pressure 51 psf/ft

FOUNDATION SOILS

Soil/Weathered Rock Parameter Estimated value

Allowable Soil Bearing Pressure Per Section 4.1

Minimum Wall Embedment Below Grade 24 inches

Coefficient of Passive Earth Pressure (Kp) 2.2

Soil Moist Unit Weight (γ) 120 pcf

Cohesion (C) 100 psf

Interface Friction Angle [Concrete on Soil / Weathered Rock] (φf) 18° / 26°

Sliding Friction Coefficient [Concrete on Soil / Weathered Rock] (μ) 0.32 / 0.4

Passive Equivalent Fluid Pressure 275 psf/ft

It is critical that the soils used for backfill of the retaining walls meet the soil parameters recommended above. If the soils available do not meet those parameters, then ECS should be contacted to provide revised values, and to confirm that only suitable soils will be used for wall backfill.

Care should be used to avoid the operation of heavy equipment to compact the wall backfill since it may overload and damage the wall. In addition, such loads are not typically considered in the design of site retaining walls, and are not provided for in our recommendations.

Wall Drainage: Retaining walls should be provided with a wall and foundation drainage system to relieve hydrostatic pressures which may develop behind the walls. This system should consist of weepholes through the wall and/or a 4-inch perforated, closed joint drain line located along the backside of the walls above the top of the footing. The drain line should be surrounded by a minimum of 6 inches of AASHTO #57 Stone wrapped with an approved non-woven geotextile, such as Mirafi 140-N or equivalent. Wall drains can consist of a 12-inch wide zone of free draining gravel, ECS Project No. 58:2033 Page 15 such as AASHTO #57 Stone, employed directly behind the wall and separated from the soils beyond with a non-woven geotextile. Alternatively, the wall drain can consist of a suitable geocomposite drainage board material. The wall drain should be hydraulically connected to the foundation drain.

4.10 CORROSION POTENTIAL

Total soluble sulfate, electrical resistivity, and pH tests were performed on one composite sample to provide an estimation of the materials’ corrosion potential. The test results are presented in the following table:

Sample Location / Depth Sulfate (mg/Kg)

Resistivity (ohms.cm) pH

Composite 1 B-01, B-04, B-05, B-06 0 to 5 ft. <200 13000 7.27

Sulfate test results indicate the soil sulfate exposure to concrete to be negligible. Type I Portland cement concrete may be used for this site. Resistivity test results indicate the onsite soils to be moderately corrosive to severely corrosive. Soil pH results indicate the soil to be mildly corrosive.

Cathodic protection or a polyethylene coating or wrap should be used to protect ferrous metal pipes and the manufacturer’s corrosion specifications should be followed. These test results should be used to determine the corrosion potential of on-site soils when in contact with various underground materials to be used in construction.

5.0 SITE CONSTRUCTION RECOMMENDATIONS

5.1 SUBGRADE PREPARATION

In a dry and undisturbed state, the upper 1-foot of the majority of the soil at the site should provide good subgrade support for fill placement and construction operations. However, when wet, this soil will degrade quickly with disturbance from contractor operations. Therefore, good site drainage should be maintained during earthwork operations, which should help maintain the integrity of the soil.

The surface of the site should be kept properly graded in order to enhance drainage of the surface water away from the proposed structures during the construction phase. We recommend that an attempt be made to enhance the natural drainage without interrupting its pattern, where possible.

The soils at the site are moisture and disturbance sensitive, and contain fines which are considered moderately erodible. Therefore, the contractor should carefully plan his operation to limit exposure of the subgrade to weather and construction equipment traffic, and provide and maintain good site drainage during earthwork operations. All erosion and sedimentation shall be controlled in accordance with sound engineering practice and current jurisdictional requirements.

5.1.1 Stripping and Grubbing

The subgrade preparation should consist of stripping all existing gravels/pavements, vegetation, topsoil, loose, poorly compacted or deleterious existing soils, existing fill (as defined in this report), and any soft or yielding materials from the 5-foot expanded building area, and any areas receiving new fill. Deeper topsoil or organic laden soils may be present in wet, low-lying, and poorly drained

ECS Project No. 58:2033 Page 16 areas. ECS should be retained to verify that topsoil and yielding surficial materials have been removed prior to the placement of structural fill or construction of structures.

5.1.2 Proofrolling

Prior to fill placement or other construction on subgrades, the subgrades should be evaluated by an ECS field technician. The exposed subgrade should be extensively proofrolled with construction equipment having a minimum axle load of 10 tons [e.g. fully loaded tandem-axle dump truck].

Proofrolling should be traversed in two perpendicular directions with overlapping passes of the vehicle under the observation of an ECS technician. This procedure is intended to assist in identifying any localized yielding materials.

Where proofrolling identifies areas that are yielding or “pumping” subgrade those areas should be repaired prior to the placement of any subsequent Structural Fill or other construction materials.

Methods of stabilization include undercutting, moisture conditioning, or chemical stabilization. The situation should be discussed with ECS to determine the appropriate procedure. Test pits may be excavated to explore the shallow subsurface materials to help in determining the cause of the observed yielding materials, and to assist in the evaluation of appropriate remedial actions to repair the subgrade.

5.2 EARTHWORK OPERATIONS

The…