B01 Attachment J01 Volume 1 - Specifications.pdf

2 West 1st Street, Suite 201, Duluth, Minnesota 55802 tel (218) 727-2626 fax (218) 722-7467 dsgw.com DULUTH I TWIN CITIES I VIRGINIA

Specifications

Mid-Atlantic Tribal Health Clinic

Roxbury, VA

IHS Project #

NS21MA002H7

DSGW Project #

021041.00

DECEMBER 3rd, 2021

VOLUME 1:

DIVISIONS 00 - 14

21041 – Mid-Atlantic Tribal Health Center

IHS # NS21MA002H7

00 01 01 - 1 PROJECT MANUAL &

REGISTRATION SHEET

SECTION 00 01 01

PROJECT MANUAL TITLE AND REGISTRATION SHEET

MID-ATLANTIC TRIBAL HEALTH CENTER

ROXBURY, VIRGINIA

DATE: DECEMBER 3rd, 2021

ARCHITECT

DSGW ARCHITECTS, INC.

2 West 1st Street, Suite 201 Duluth, MN 55802 Phone: 218-727-2626

IHS PROJECT NO.: NS21MA002H7

DSGW PROJECT NO.: 021041.00

STRUCTURAL ENGINEER CIVIL ENGINEER

NORTHLAND CONSULTING ENGINEERS L.L.P. KIMLEY-HORN AND ASSOCIATES, INC.

102 South 21st Avenue West, Suite 1 421 Fayetteville Street, Suite 600 Duluth, Minnesota 55806 Raleigh, NC 27601 Phone: 218-727-5995 Phone: 651-643-4197

MECHANCIAL/ELECTRICAL ENGINEER

EDI-DOLEJS CONSULTING ENGINEERS

1112 North 5th Street Minneapolis, MN 55411 Phone: 612-343-5965

I hereby certify that these Drawings and Specifications were prepared by me or under by direct supervision and that I am a duly registered Architect under the laws of the State of Virginia.

© DSGW. All rights reserved.

The architectural works depicted herein are the sole property of DSGW and may not be constructed or used without its express written permission. No permission to modify or reproduce any of these architectural works, including without limitation the construction of any building, is expressed or should be implied from delivery of preliminary drawings or unsealed construction drawings. Permission to construct the building depicted in sealed construction drawings is expressly conditioned on the full and timely payment of all fees otherwise due DSGW and, in the absence of any written agreement to the contrary, is limited to a one-time use on the site indicated on these plans.

END OF SECTION

IHS # NS21MA002H7

00 01 10 - 1 TABLE OF CONTENTS

SECTION 00 01 10

TABLE OF CONTENTS

MID-ATLANTIC TRIBAL HEALTH CENTER

ROXBURY, VIRGINIA

VOLUME 1 – DIVISIONS 00 - 14

DIVISION 00 -- PROCUREMENT AND CONTRACTING REQUIREMENTS

00 01 01 – Project Manual Title and Registration Sheet 00 01 10 – Table of Contents 00 01 15 – Schedule of Drawings 00 31 00 – Available Project Information 00 43 25 – Request for Approval of Substitution 00 72 00 – General Conditions 00 73 00 – Supplementary General Conditions

DIVISION 01 -- GENERAL REQUIREMENTS

01 10 00 – Summary 01 20 00 – Price and Payment Procedures 01 23 00 – Alternates 01 30 00 – Administrative Requirements 01 40 00 – Quality Requirements 01 50 00 – Temporary Facilities and Controls 01 60 00 – Product Requirements 01 70 00 – Execution and Closeout Requirements 01 78 00 – Closeout Submittals

DIVISION 02 – EXISTING CONDITIONS

02 41 00 – Demolition

DIVISION 03 – CONCRETE

03 10 00 – Concrete Forming 03 20 00 – Concrete Reinforcing 03 30 00 – Cast in Place Concrete 03 41 13 – Precast Concrete Hollow Core Planks

DIVISION 04 -- MASONRY

04 20 00 – Unit Masonry 04 72 00 – Cast Stone Masonry 04 73 00 – Manufactured Stone Masonry

DIVISION 05 -- METALS

05 12 00 – Structural Steel Framing 05 31 00 – Steel Decking 05 40 00 – Cold Formed Metal Framing 05 50 00 – Metal Fabrications

DIVISION 06 -- WOOD, PLASTICS, AND COMPOSITES

06 10 00 – Rough Carpentry 06 15 00 – Wood Decking 06 17 53 – Shop Fabricated Wood Trusses 06 18 00 – Glued-Laminated Construction 06 20 00 – Finish Carpentry 06 41 00 – Architectural Wood Casework

00 01 10 - 2 TABLE OF CONTENTS

06 82 19 – Fiberglass Reinforced Wall Panels

DIVISION 07 -- THERMAL AND MOISTURE PROTECTION

07 11 13 – Bituminous Damproofing 07 17 13 – Bentonite Panel Waterproofing 07 21 00 – Thermal Insulation 07 25 00 – Weather Barriers 07 31 13 – Asphalt Shingles 07 42 13 – Metal Wall Panels 07 52 10 – Specialty Roof System 07 53 00 – Elastomeric Membrane Roofing 07 62 00 – Sheet Metal Flashing and Trim 07 72 33 – Roof Hatches and Vents 07 84 00 – Firestopping 07 90 05 – Joint Sealers

DIVISION 08 -- OPENINGS

08 11 13 – Hollow Metal Door and Frames 08 14 16 – Flush Wood Doors 08 31 00 – Access Doors and Panels 08 33 23 – Overhead Coiling Doors 08 42 29 – Automatic Entrance Doors 08 43 13 – Aluminum Framed Storefronts 08 71 00 – Door Hardware 08 80 00 – Glazing 08 91 00 - Louvers

DIVISION 09 -- FINISHES

09 21 16 – Gypsum Board Assemblies 09 30 00 - Tiling 09 51 00 – Acoustical Ceilings 09 65 00 – Resilient Flooring 09 68 13 – Tile Carpeting 09 84 00 – Acoustic Room Components 09 90 00 – Painting and Coating

DIVISION 10 -- SPECIALTIES

10 11 01 – Visual Display Boards 10 21 23 - Cubicles 10 21 13.19 – Solid Plastic Toilet Compartments 10 26 01 – Handrails and Wall Protection 10 28 00 – Toilet Accessories 10 44 00 – Fire Protection Specialties 10 51 26 – Plastic Lockers 10 73 13 - Awnings 10 73 16 – Canopies 10 75 00 – Flagpoles

DIVISION 12 -- FURNISHINGS

12 24 13 – Window Shade Systems

DIVISION 14 – CONVEYING SYSTEMS

14 20 10 – Passenger Elevators

00 01 10 - 3 TABLE OF CONTENTS

VOLUME 2 – DIVISIONS 21 - 33

DIVISION 21 -- FIRE SUPPRESSION

21 00 01 – Fire Protection Certification 21 10 00 – Water-Based Fire Protection Systems

DIVISION 22 -- PLUMBING

22 00 01 – Plumbing Certification 22 00 10 – General Provisions 22 05 00 – Common Work Results for Plumbing 22 05 13 – Common Motor Requirements for Plumbing Equipment 22 05 19 – Meters and Gages for Plumbing Piping 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 00 – Plumbing Insulation 22 11 16 – Domestic Water Piping 22 11 19 – Domestic Water Piping Specialties 22 11 23 – Domestic Water Pumps 22 11 23.13 – Domestic Water Packaged Booster Pump System 22 13 16 – Sanitary Waste and Vent Piping 22 13 19 – Sanitary Waste Piping Specialties 22 14 13 – Facility Storm Drainage Piping 22 14 23 – Storm Drainage Piping Specialties 22 34 00 – Liquid Propane, Fuel-Fired Domestic-Water Heaters 22 40 00 – Plumbing Fixtures 22 45 00 – Emergency Plumbing Fixtures 22 47 00 – Drinking Fountains and Water Coolers 22 61 13 – Compressed-Air Piping for Dental Facilities 22 62 13 – Vacuum Piping for Dental Facilities

DIVISION 23 -- HEATING, VENTILATING, AND AIR-CONDITIONING (HVAC)

23 00 01 – Mechanical Certification 23 00 10 – General Provisions 23 05 00 – Common Work Results for HVAC 23 05 13 – Common Motor Requirements for HVAC Equipment 23 05 16 – Expansion Fittings and Loops for HVAC Piping 23 05 19 – Meters and Gages for HVAC Piping 23 05 23 – General-Duty Valves for HVAC Piping 23 05 29 – Hangers and Supports for HVAC Piping and Equipment 23 05 48 – Vibration Controls for HVAC Piping and Equipment 23 05 53 – Identification for HVAC Piping and Equipment 23 05 93 – Testing, Adjusting, and Balancing for HVAC 23 07 00 – HVAC Insulation 23 08 00 – Commissioning of HVAC 23 09 00 – Instrumentation and Control for HVAC 23 09 93 – Sequence of Operations for HVAC Controls 23 11 16 – Facility Liquified-Petroleum Gas Piping 23 21 13 – Hydronic Piping and Specialties 23 21 15 – Propylene Glycol System 23 21 23 – Hydronic Pumps 23 31 13 – Metal Ducts 23 33 00 – Air Duct Accessories 23 34 23 – HVAC Power Ventilators 23 36 00 – Air Terminal Units

00 01 10 - 4 TABLE OF CONTENTS

23 37 13 – Grilles, Registers and Diffusers 23 51 00 – Breechings, Chimneys, and Stacks 23 52 16 – Fire-Tube Condensing Boilers 23 62 00 – Packaged Compressor and Condenser Units 23 81 26 – Split-System Air-Conditioners 23 82 39 – Unit Heaters 23 83 16 – Radiant-Heating Hydronic Piping

DIVISION 26 – ELECTRICAL

26 00 01 – Electrical Certification 26 00 10 – General Provisions for Electrical Work 26 00 11 – Electrical Alternates 26 01 00 – Construction Power and Lighting 26 04 00 – Underground Electrical Service 26 04 45 – Electrical Connections to Equipment 26 05 00 – Common Work Results for Electrical 26 05 19 – Low-Voltage Electrical Power Conductors and Cables 26 05 23 – Control-Voltage Electrical Power Cables 26 05 26 – Grounding and Bonding for Electrical Systems 26 05 29 – Hangers and Support for Electrical Systems 26 05 33 – Raceways and Boxes for Electrical Systems 26 05 53 – Identification for Electrical Systems 26 09 24 – Local Low-voltage Lighting Control System 26 09 26 – Relay Based Lighting Control (Network) 26 24 13 – Switchboards 26 24 16 – Panelboards 26 27 26 – Wiring Devices 26 28 13 – Fuses 26 28 16 – Enclosed Switches and Circuit Breakers 26 29 13 – Enclosed Controllers 26 29 23 – Variable-Frequency Motor Controllers 26 51 19 – LED Interior Lighting 26 52 19 – Emergency and Exit Lighting 26 56 19 – LED Exterior Lighting 26 70 00 – Pathways for Communications and Security Systems 26 71 11 – Digital, Addressable Fire-Alarm System

DIVISION 27 – COMMUNICATIONS

27 00 01 – Communications Certification 27 00 10 – General Provisions 27 01 00 – Operation, Maintenance & Warranty 27 05 00 – Common Work Results for Communications 27 05 26 – Grounding for Communications 27 05 28 – Pathways for Communications 27 05 53 – Identification for Communications Systems 27 06 00 – Schedules for Communications 27 08 00 – Testing of Communications Systems 27 10 00 – Structured Cabling Requirements 27 11 00 – Communications Equipment Room Fittings 27 11 13 – Communications Entrance Protection 27 11 16 – Cabinets, Racks, Frames & Enclosures 27 11 19 – Patch Panels 27 11 23 – Cable Management & Ladder Rack 27 11 26 – Rack Mounted Power Protection & Power Strips 27 13 23 – Optical Fiber Back-Bone Cabling 27 15 13 – Copper Horizontal Cabling 27 15 43 – Faceplates & Connectors 27 16 19 – Patch Cords & Cross Connect Wire

00 01 10 - 5 TABLE OF CONTENTS

27 51 16 – Public Address Systems

DIVISION 28 – ELECTRONIC SAFETY AND SECURITY

28 00 01 – Security Certification 28 00 10 – General Provisions 28 05 28 – Pathways for Electronic Safety and Security 28 23 13 – Video Surveillance Control and Management Systems 28 61 00 – CCTV Cabling System

DIVISION 31 -- EARTHWORK

31 22 00 – Grading 31 23 16 – Excavation 31 23 23 – Fill

DIVISION 33 – UTILITIES

33 41 00 - Subdrainage

Health Center 00 01 15 - 1 SCHEDULE OF DRAWINGS

SECTION 00 01 15

SCHEDULE OF DRAWINGS

MONACAN HEALTH CLINIC

MADISON HEIGHTS, VIRGINIA

SHEET TITLE

0- Cover Sheet A0.1 Title Sheet

CIVIL

C01 COVER SHEET

C02 GENERAL NOTES

C03 EXISTING CONDITIONS

C04 DEMOLITION AND PHASE I E&SC PLAN

C05 PHASE II E&SC PLAN

C06 EROSION AND SEDIMENT CONTROL NARRATIVE

C07 POLLUTION PREVENTION PLAN

C08 SITE PLAN

C09 SITE DETAILS

C10 GRADING PLAN

C11 DRAINAGE AREAS AND WATER QUANTITY PLAN

C12 WATER QUALITY PLAN

C13 STORM SEWER PROFILES AND CALCULATIONS

C14 DRAINAGE DETAILS

C15 UTILITY PLAN

C16 UTILITY DETAILS

C17 PLANTING PLAN

C18 PLANTING NOTES AND DETAILS

STRUCTURAL

S0.0 ISOMETRIC VIEWS

S0.1 STRUCTURAL NOTES

S0.2 ROOF LOADING/ CANOPY FRAMING PLAN/ SECTIONS/

STRUCTURAL NOTES

S1.1 TYPICAL CONCRETE DETAILS

S1.2 TYPICAL CMU DETAILS

S1.3 TYPICAL STEEL DETAILS

S1.4 TYPICAL LIGHT GUAGE STEEL DETAILS

S1.5 TYPICAL WOOD DETAILS

S2.1 FOUNDATION PLAN AREA "A"

S2.2 FOUNDATION PLAN AREA "B"

S2.3 LEVEL 2/ LOW ROOF FRAMING PLAN AREA "A"

S2.4 LEVEL 2/ LOW ROOF FRAMING PLAN AREA "B"/ UPPER

ROOF FRAMING PLAN

S2.5 GARAGE PLANS/ SECTIONS

S4.1 FRAMING SECTIONS/ DETAILS

S4.2 FRAMING SECTIONS/ DETAILS

S4.3 FRAMING SECTIONS/ DETAILS

ARCHITECTURAL

A1.1 Life Safety Plan & Summary A1.2 Architectural Site Plan A2.1 First Floor - Overall Plan A2.1A First Floor Plan - Area A A2.1B First Floor Plan - Area B A2.2 Second Floor Plan

Health Center 00 01 15 - 2 SCHEDULE OF DRAWINGS

A2.3 First & Second Floor - Finish Plan A2.4 First & Second Floor - Furniture Plan A2.5 Outbuilding Plans and Sections A2.6 Roof Plan A3.1 First Floor RCP - Overall Plan A3.1A First Floor RCP - Area A A3.1B First Floor RCP - Area B A3.2 Second Floor RCP A4.1 Door Schedule & Types A4.2 Window Types and Details A4.3 Finish Schedule A5.1 Exterior Elevations A5.2 Exterior Elevations A6.1 Building Sections A6.2 Wall Sections A6.3 Wall Sections A7.1 Interior Elevations A7.2 Interior Elevations A7.3 Interior Elevations A7.4 Millwork Sections A8.1 Enlarged Plans and Sections - Elevator, Stair #1 & Stair #2 A9.1 Fixture Mounting Heights

MECHANICAL

M0.1 MECHANICAL TITLE SHEET

M0.2 SITE PLAN - MECHANICAL

M1.1 FIRST FLOOR - AREA B - FIRE PROTECTION

M1.2 FIRST FLOOR PLAN - AREA B - FIRE PROTECTION

M1.3 SECOND FLOOR PLAN - FIRE PROTECTION

M2.0 UNDERFLOOR PLAN - AREA A - PLUMBING

M2.1 UNDERFLOOR PLAN - AREA B - PLUMBING

M2.2 FIRST FLOOR PLAN - AREA A - PLUMBING

M2.3 FIRST FLOOR PLAN - AREA B - PLUMBING

M2.4 SECOND FLOOR PLAN - PLUMBING

M2.5 ENLARGED PLANS - PLUMBING

M2.6 PLUMBING RISER DIAGRAM - WASTE AND VENT

M2.7 PLUMBING RISER DIAGRAM - WASTE AND VENT

M2.8 PLUMBING RISER DIAGRAM - WASTE AND VENT

M2.9 PLUMBING RISER DIAGRAM - DOMESTIC WATER

M2.10 PLUMBING RISER DIAGRAM - DOMESTIC WATER

M2.11 PLUMBING RISER DIAGRAM - DOMESTIC WATER

M3.1 FIRST FLOOR PLAN - AREA A - PIPING

M3.2 FIRST FLOOR PLAN - AREA B - PIPING

M3.3 SECOND FLOOR PLAN - PIPING

M4.1 FIRST FLOOR PLAN - AREA A - HVAC

M4.2 FIRST FLOOR PLAN - AREA B - HVAC

M4.3 SECOND FLOOR PLAN - HVAC

M5.1 ROOF PLAN - AREA A - MECHANICAL

M5.2 ROOF PLAN - AREA B - MECHANICAL

M6.1 MECHANICAL SCHEDULES

M6.2 MECHANICAL SCHEDULES

M7.1 MECHANICAL DETAILS

M7.2 MECHANICAL DETAILS

M7.3 MECHANICAL DETAILS

M7.4 MECHANICAL DETAILS

Health Center 00 01 15 - 3 SCHEDULE OF DRAWINGS

ELECTRICAL

E0.1 ELECTRICAL TITLE SHEET

E1.1 SITE PLAN - ELECTRICAL

E2.1 FIRST LEVEL FLOOR PLAN AREA A - LIGHTING

E2.2 FIRST LEVEL FLOOR PLAN AREA B - LIGHTING

E2.3 SECOND LEVEL FLOOR PLAN - LIGHTING

E3.1 FIRST LEVEL FLOOR PLAN AREA A - POWER

E3.2 FIRST LEVEL FLOOR PLAN AREA B - POWER

E3.3 SECOND LEVEL FLOOR PLAN - POWER

E3.4 ROOF PLAN - POWER

E4.1 FIRST LEVEL FLOOR PLAN AREA A - SYSTEMS

E4.2 FIRST LEVEL FLOOR PLAN AREA B - SYSTEMS

E4.3 SECOND LEVEL FLOOR PLAN - SYSTEMS

E5.1 POWER RISER DIAGRAM

E5.2 ENLARGED FLOOR PLANS - ELECTRICAL

E6.1 SCHEDULES - ELECTRICAL

E6.2 SCHEDULES - ELECTRICAL

E6.3 SCHEDULES - ELECTRICAL

E7.1 DETAILS - ELCECTRICAL

E7.2 DETAILS - ELCECTRICAL

E7.3 DETAILS - ELCECTRICAL

E7.4 DETAILS – ELCECTRICAL

EQUIPMENT

Q2.1A FIRST FLOOR - EQUIPMENT PLAN - AREA A

Q2.1B FIRST FLOOR - EQUIPMENT PLAN - AREA B

Q2.2 SECOND FLOOR - EQUIPMENT PLAN

Q4.1 EQUIPMENT SCHEDULE

Q4.2 EQUIPMENT SCHEDULE

Q4.3 EQUIPMENT SCHEDULE

Health Center 00 31 00 - 1 AVAILABLE PROJECT INFORMATION

IHS # NS21MA002H7

SECTION 00 31 00

AVAILABLE PROJECT INFORMATION

PART 1 GENERAL

1.01 GEOTECHNICAL REPORT

A. ECS Mid Atlantic, LLC, Geotechnical Engineering Report for Mid-Atlantic Tribal Health Center AKA Roxbury Medical Clinic, dated July 12, 2021 appended to this section.

PART 2 PRODUCTS (NOT USED)

PART 3 EXECUTION (NOT USED)

ECS Mid-Atlantic, LLC Report of Subsurface Exploration and Geotechnical Engineering Services

Roxbury Medical Clinic 2401 Roxbury Road Charles City, Virginia 23030

Mr. David Verdis, EIT Kimley-Horn and Associates, Inc.

1700 Willow Lawn Drive, Suite 200 Richmond, Virginia 23230

ECS Project Number 03:13692

July 12 , 2021

July 12, 2021

Mr. David Verdis, EIT Kimley-Horn and Associates, Inc.

1700 Willow Lawn Drive, Suite 200 Richmond, Virginia 23230

ECS Project No. 03:13692

Reference: Report of Subsurface Exploration and Geotechnical Engineering Services

Roxbury Medical Clinic 2401 Roxbury Road Charles City, Virginia 23030

Dear Mr. Verdis:

ECS Mid-Atlantic, LLC (ECS) has completed this report of subsurface exploration and geotechnical engineering services for the above-referenced project. Our services were performed in general accordance with our Proposal No. 03:15021-GP dated 02/18/21 and authorized through Project Order Number ECS000-21-03RIC executed 05/06/21. This report presents our understanding of the geotechnical aspects of the project, the results of the field exploration and laboratory testing, and our design and construction recommendations.

It has been our pleasure to be of service to Kimley-Horn and Associates, Inc. during the design phase of this project. We would appreciate the opportunity to remain involved during the continuation of the design phase, and we would like to provide our services during the construction phase to verify the assumptions of the subsurface conditions made for this report. Should you have any questions concerning the information contained in this report, or if we can be of further assistance to you, please contact us.

Respectfully submitted, ECS Mid-Atlantic, LLC

Shashank Suresh, E.I.T. Robert C. Moss, III, P.E.

Geotechnical Staff Project Manager Principal Engineer Ssuresh@ecslimited.com Rmoss@ecslimited.com

Distribution: Client via email [ David.Verdis@kimley-horn.com ] mailto:Ssuresh@ecslimited.com mailto:Rmoss@ecslimited.com mailto:David.Verdis@kimley-horn.com

TABLE OF CONTENTS

Report of Subsurface Exploration and Geotechnical Engineering Services Roxbury Medical Clinic

2401 Roxbury Road Charles City, Virginia 23030

EXECUTIVE SUMMARY .................................................................................................................. i

1.0 INTRODUCTION

1.1 General

1.2 Scope of Services

1.3 Authorization

2.0 PROJECT INFORMATION

2.1 Site Location and Current Site Conditions

2.2 Proposed Construction

3.0 FIELD EXPLORATION

3.1 Field Exploration Program

3.2 Site Geology

3.3 Soil Survey

3.4 Subsurface Characterization

3.5 Groundwater Observations

3.6 Laboratory Testing

4.0 Design Recommendations

4.1 Building Foundation Design

4.2 Floor Slab Design

4.3 Drainage Considerations

4.4 Seismic Design

4.5 Site Retaining Wall Design

4.6 Pavement Design

5.0 SITE CONSTRUCTION RECOMMENDATIONS

5.1 Subgrade Preparation and Earthwork Operations

5.2 Foundation Observations

5.3 Utility Installation

6.0 CLOSING

APPENDICES

Appendix A – Drawings

• Site Location Diagram

• Boring Location Diagram

Appendix B – Field Operations

• Reference Notes for Boring Logs

• Boring Logs (B-1 through B-4 and P-1 through P-5)

• Subsurface Soil Profile (A-A’)

Appendix C – Laboratory Testing

• Laboratory Test Results Summary

• Liquid and Plastic Limits Test Report

Roxbury Medical Clinic July 12, 2021 ECS Project No.03:13692 Page i

EXECUTIVE SUMMARY

The following summarizes the project characteristics and the main findings of the subsurface exploration and geotechnical engineering analysis. Information from the executive summary should not be utilized in lieu of reviewing the entire geotechnical report.

• The project site is located at 2401 Roxbury Road (SR 106) approximately 1.8 miles south of its intersection with US Route 60 in Charles City, Virginia. The site contains 12.22 acres and is currently occupied by a wood truss manufacturing operation with a mostly open and gravel surfaced area. Portions of the site are covered with concrete paving. Based on aerial imagery from publicly available sources, the site slopes down from east to west with an approximate grade change of about 10 feet, corresponding to maximum and minimum elevations of about EL. 132 and 122 feet, respectively.

• The proposed project will include the development of a medical office building and associated infrastructure.

The building will contain 15,000 to 20,000 square feet and be 1 story in height and of wood and metal frame construction with a slab on grade floor. Finished floor elevations are anticipated at about EL. 126 feet. No below grade space is anticipated for the project. Maximum column and wall loads for the building are expected to be 75 kips and 3 kips/ft, respectively. Parking for about 180 vehicles will be provided. Pavements will be of asphalt construction. Maximum traffic loading for the drive lanes is estimated to be 350 vehicles per day. It is anticipated that the site will be graded by cut and fill with maximum cut and fill depths of about 3 and 4 feet, respectively. A site retaining wall will be located on the northeast boundary of the site.

• The subsurface conditions were explored by drilling 9 soil test borings (B-1 through B-4 and P-1 through P-5) within the project boundaries. A truck mounted drill rig was utilized to drill the soil test borings. The borings were advanced to the planned boring termination depths of 10 and 20 feet below the ground surface. The soil borings B-2 and B-3 encountered approximately 8 inches of concrete over 6 and 8 inches of stone aggregate material. Approximately 6 to 8 inches of stone aggregate material were encountered in rest of the soil boring locations. Below the surface cover, FILL was encountered at soil boring locations B-3 and P-5 to depth of about 2 feet. Underneath FILL/Surface Cover to the depths explored, marine deposits consisting mostly of Clayey SAND (SC), Silty SAND (SM), Lean CLAY (CL), and Fat CLAY (CH) were encountered.

• An observed 2 feet of undocumented FILL are present in the proposed building footprint and pavement areas.

The FILL consisted of mostly Lean CLAY (CL) with varying amounts of stone aggregates. Petroleum odor was detected in the top 2 feet of FILL encountered at soil boring location P-5. It is the intent of this report to allow suitable and stable FILL to remain in place below floor slabs and pavements. However, all FILL should be removed from below foundations to expose stable, natural subgrade soils.

• Based on the results of our borings, the proposed building structure can be supported by shallow spread footing foundations with a floor slab-on-grade. The footings should bear in stable, undisturbed natural soils, properly placed Engineered Fill, or Foundation Excavation Backfill. In this regard, it may be necessary to undercut the foundation excavations so as to penetrate the existing FILL and expose stable, natural soils.

Design bottom of foundation elevations can be reestablished by backfilling the excavations with Foundation Excavation Backfill (VDOT Size No. 57 Stone). Both column (square) and continuous (strip) spread footings having a minimum width of 24 inches can be dimensioned for a net allowable bearing capacity of 2,500 psf.

Foundation bearing soils on this site are expected to have low to moderate expansive (shrink-swell) potential.

Foundations should be embedded a minimum of 24 inches below finished exterior grades for bearing capacity, frost protection, and shrink-swell considerations.

ECS Project No.03:13692 Page ii

• Based on the subsurface profile reflected by the test borings, the Seismic Site Class is estimated as Class D. If it is determined that significant cost savings advantage could be gained with an improved Site Class, additional site testing could be performed to measure actual shear wave velocities using ReMi test methods along with a site-specific analysis. ECS can provide additional consultation upon request.

• Based on the results of our borings, it appears that the soils that will be exposed as pavement subgrades will consist mainly of Lean CLAY (CL) and Clayey SAND (SC). Considering the variability of the subgrade materials and the presence of cohesive soils, we recommend a maximum design CBR value of 8 be used in planning the pavement sections. Conventional pavement sections can be employed on this site.

• The groundwater table was encountered at depths of 12 to 14 feet below existing grades corresponding to approximate elevations of EL. 116 to EL. 110 feet. Based on the assumed proposed grades, groundwater table is not anticipated to impact excavations shallower than about 12 to 14 feet below existing grades. However, seepage from shallow perched water into excavations could still occur depending on the weather conditions at the time of construction. The need for sump pumping of perched groundwater which seeps into excavations should be anticipated. For excavation much below the level of the groundwater table, well pointing might be required.

• Most, but not all of the soils available from cuts on this site are expected to be suitable for reuse as Structural

Fill. Fat CLAY (CH) and Elastic SILT (MH) are considered limited for reuse as Structural Fill due to plasticity.

Materials satisfying that specification may be available on site but would require selective mining.

• Rock Excavation is not expected to be required on this project.

ECS Project No.03:13692 Page 1

1.0 INTRODUCTION

1.1 GENERAL

The purpose of this study was to explore the soil and groundwater conditions at the site in order to develop geotechnical related engineering recommendations to aid in the design of the proposed building foundations and floor slabs-on-grade and the site pavements and to aid in development of earthwork specifications for the project.

We accomplished these purposes by drilling soil test borings across the site and analyzing the soil samples to evaluate pertinent engineering properties. On this basis we developed our geotechnical engineering findings. No warranties are expressed or implied. No investigation for the presence of contamination of the soil, water, or air at or around this site was performed as part of this study.

1.2 SCOPE OF SERVICES

To obtain the necessary geotechnical information required for design of the project, nine (9) soil test borings were completed at locations selected by ECS. A laboratory-testing program was implemented to characterize the physical and engineering properties of the subsurface soils.

To complete the scope of services, ECS was provided with conceptual layout plan entitled Mid-Atlantic Tribes Chickahominy Clinic Option I prepared DSGW Architecture. This drawing indicated proposed building and parking lot layout.

This report discusses our exploratory and testing procedures, presents our findings and evaluations, and includes the following:

• Observations from our site reconnaissance including current site conditions, surface drainage features, and unusual site features.

• A description of the field exploration and laboratory tests performed and discussion of subsurface conditions.

• Final logs of the soil borings and records of the field exploration prepared in accordance with the standard practice for geotechnical engineering. A boring location plan is included, and the laboratory test results are plotted on the boring logs and included on a laboratory test summary.

• Descriptions of subsurface conditions including pavement, topsoil, FILL or debris, and groundwater depths and strata depths.

• Recommended allowable soil bearing pressure and design parameters for the building foundations and estimates of predicted foundation settlement. Recommendations for foundation subgrade improvement, if indicated.

• Recommendations for seismic site classification in accordance with the International Building Code (IBC) 2015, Section 1613 based on the soil borings and our experience in this geologic setting.

• Recommendations for a subgrade modulus for slab design and for underslab drainage and moisture protection. Recommendations for slab subgrade improvement, if indicated.

• Recommendations for development of earthwork specifications. Evaluation of the on-site soil characteristics encountered in the soil borings. Discussion of the suitability of the on-site materials for reuse as Structural Fill

ECS Project No.03:13692 Page 2 to support foundations, slabs, and pavements. Recommendations for compaction requirements and suitable on and off-site borrow materials.

• Evaluation of ground water and rock conditions and their impacts on the proposed construction.

• Recommendations for additional testing and/or consultation that may be required to complete the exploration for this site.

The recommendations contained herein were developed from the data obtained in the soil test borings which indicate subsurface conditions at these specific locations at the time of exploration. Soil conditions may vary between the borings. If during the course of construction variations appear evident, the Geotechnical Engineer should be informed so that the conditions can be addressed.

1.3 AUTHORIZATION

Our services were provided in general accordance with our Proposal No. 03:15021-GP dated 02/18/21, and authorized through Kimley-Horn and Associates, Inc. Project Order Number ECS000-21-03RIC executed 05/06/21.

2.0 PROJECT INFORMATION

2.1 SITE LOCATION AND CURRENT SITE CONDITIONS

The project site is located at 2401 Roxbury Road (SR 106) approximately 1.8 miles south of its intersection with US Route 60 in Charles City, Virginia. The site contains 12.22 acres and is currently occupied by a wood truss manufacturing operation with a mostly open and gravel surfaced area. Portions of the site are covered with concrete paving. Based on aerial imagery from publicly available sources, the site slopes down from east to west with an approximate grade change of about 10 feet, corresponding to maximum and minimum elevations of about EL. 132 and 122 feet, respectively. Please refer to the Figure 2.1-1 below for further detail regarding existing site conditions.

Figure 2.1-1 Site Location

Approximate Site Boundary

ECS Project No.03:13692 Page 3

2.2 PROPOSED CONSTRUCTION

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

Table 2.2-1 Summary of Proposed Construction

SUBJECT DESIGN INFORMATION / ASSUMPTIONS

Building Medical Office Number of Stories One-story structure with concrete slab-on-grade floors Building Footprint Area 15,000 to 20,000 square feet Framing Wood and Structural Steel frame construction Max. Column Loads 75 kips Max. Wall Loads 3 kips per linear foot Assumed Finish Floor Elevation EL. 128 +/- feet

Parking for approximately 180 vehicles will be provided. Pavements will be of asphalt construction. Maximum traffic loading for the drive lanes is estimated to be 350 vehicles per day. It is anticipated that the site will be graded by cut and fill with maximum cut and fill depths of about 2 or 3 feet. An approximately 215 linear foot site retaining wall with a maximum height of about 4± feet will be located in the northeast boundary of the site.

3.0 FIELD EXPLORATION

3.1 FIELD EXPLORATION PROGRAM

The subsurface conditions were explored by drilling 4 soil test borings within the proposed medical office building footprint to a depth of 20 feet below existing grades (B-1 through B-4) and 5 soil test borings in the pavement areas to a depth of 10 feet below existing grade (P-1 through P-5). Approximate soil test boring locations are indicated on the Boring Location Diagram of Appendix A. A truck mounted CME-45B drill rig was utilized to drill the soil test borings.

Boring locations were identified in the field by ECS personnel using a hand-held GPS device and using existing site features as reference prior to the mobilization of our drilling subcontractor, Geotech-Environmental Services, Inc.

Ground surface elevations noted on our boring logs were obtained from topographic information indicated on the drawings provided to us. Based on the above-mentioned methods, the boring locations and elevations should be considered approximate and should not be used for design purposes.

Representative soil samples were obtained by means of the split-barrel sampling procedure in accordance with ASTM Specification D1586. In this procedure, a 2-inch O.D., split-barrel sampler is driven into the soil a distance of 24 inches by a 140-pound hammer falling 30 inches. The number of blows required to drive the sampler through the second and third 6-inch interval is termed the Standard Penetration Test (SPT) value and is indicated for each sample on the boring logs. This value can be used as a qualitative indication of the in-place relative density of cohesionless soils and, in a less reliable way, the relative consistency of cohesive soils. These indications are qualitative, since many factors such as drill crews, drill rigs, drilling procedures, and hammer-rod-sampler assemblies can affect the Standard Penetration resistance value and prevent a direct correlation between blow counts and strength and compressibility of soils. Samples were taken continuously to a depth of 10 feet and at 5-foot intervals thereafter.

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After recovery, representative portions of each soil sample were removed from the sampler and sealed in glass jars. The samples were taken to our laboratory in Richmond, Virginia for visual classification and laboratory testing.

The samples will be retained for a period of 60 days following the submission of this report, at which point they will be discarded unless instructed otherwise.

3.2 SITE GEOLOGY

The project site is located about 16 miles east of The Fall Line in the Coastal Plain physiographic geologic region.

The Fall Line marks the northeast-southwest trending zone in the Mid-Atlantic States where bedrock dipping down to the southeast submerges below the surface. To the west, the soil stratigraphy is dominated by residuum and rock outcrops. To the east, the soil stratigraphy is dominated by marine Clays and Sands deposited by advancing and retreating ocean/estuarine shorelines. At the transition, marine deposits lap over piedmont rock.

Based on the USGS Geologic Map of Virginia (1993), the project site is located in the Coastal Plain and contains

3.6 to 2.8 million-year-old, Pliocene sediments of the Bacons Castle Formation deposited in a shallow, estuarine environment. These are primarily sands and sandy clays. These overlie 20.4 to 4.9 million-year-old marine sediments of the Chesapeake Group deposited in late Miocene to early Pliocene times in a shallow sea. These are primarily silty sands in this area. Rock was not encountered within the maximum 20-foot depth explored. Geologic mapping of the site vicinity is provided in Figure 3.2-1 below.

Figure 3.2-1 Site Geology

(Geologic Map of Virginia (1993))

Approximate Site Location

Bacons Castle Formation, Brown:

(Pliocene Sand and Clay)

Chesapeake Group, Tan:

(Miocene/Pliocene Silty

Sand and Clay)

Alluvium, Yellow :

(Pleistocene Clays and Sand)

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3.3 SOIL SURVEY

A review of the USDA soil survey indicates the soils mapped for the site consist of the following soil series.

• Craven-Remlik Complex (16C) Series: Clayey Marine Sediment being moderately well drained and possessing a low to moderate shrink-swell potential.

• Emporia Gravelly Fine Sandy Loam and Emporia-Kempsville Complex (21B, 23B) Series: Gravelly, Loamy, and Clayey Marine Sediment being moderately drained and possessing a low to moderate shrink-swell potential.

• Nervac-Remlik Complex (35E) and Slagle Fine Sandy Loam (42B) Series: Loamy and Clayey Marine Sediment being moderately well drained and possessing a low to moderate shrink-swell potential.

Based on our visual classification of the soils encountered and the laboratory test results, the soils on this site are considered to have a low (SC, SM, and CL) to moderate (CH) expansive potential. Further detail regarding the soil survey mapping is shown in Figure 3.3-1 below.

3.4 SUBSURFACE CHARACTERIZATION

The subsurface conditions encountered were generally consistent with published geological mapping. The following sections provide generalized characterizations of the soil strata. Please refer to the boring logs and generalized subsurface soil profile in Appendix B for further details.

Table 3.4-1 Subsurface Characterization Approximate

Depth Stratum Description Ranges of

SPT(1) N-values (blows per foot)

(Surface cover) n/a The surface cover consisted of approximately 6 to 10 inches of gravel or 8 inches of concrete overlying 6 or 8 inches of gravel (B-2 and B-3).

N/A

Surface Cover to 2’

FILL – I Stiff to very stiff, SANDY LEAN CLAY (CL).

FILL was encountered in borings B-3 and P-5.

Petroleum odors encountered in fill stratum at boring P-5.

10 to 30

Surface Cover or 2’ to termination depth

Marine Deposits - II

Loose to dense, Clayey SAND (SC) and Silty SAND (SM) and stiff to very stiff, Lean CLAY (CL) and Fat CLAY (CH). All borings were terminated in this stratum.

5 to 33

Notes: (1) Standard Penetration Testing.

3.5 GROUNDWATER OBSERVATIONS

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 not immediately apparent at the time of this exploration.

The highest groundwater observations are normally encountered in the late winter and early spring. Groundwater conditions are noted in more detail on the Soil Test Boring Logs and Subsurface Soil Profiles included in Appendix B.

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Groundwater Table

Observations for groundwater were made during sampling and upon completion of the drilling operations at each boring location. In auger drilling operations, water is not introduced into the boreholes, and the groundwater position can often be determined by observing water flowing into or out of the boreholes. Furthermore, visual observation of the soil samples recovered during the auger drilling exploration can often be used in evaluating the groundwater conditions. The groundwater table was encountered at depths of 12 to 14 feet below existing grades corresponding to approximate elevations of EL. 116 to EL. 110 feet.

Perched Water

Perched water generally originates from surface water which infiltrates downward through the soil profile until a less permeable layer is encountered, a depth at which it tends to accumulate and is also more present during the wetter times of the year. Perched water was encountered in the top 10 feet at 2 of the 9 soil test borings. Localized pockets of perched water could be present on site and impact the excavations for footings and utilities, depending on the seasonal conditions at the time of construction. The presence of perched water should diminish in the warmer, summer months and once the site is graded.

3.6 LABORATORY TESTING

An experienced geologist visually classified each soil sample from the test borings on the basis of texture and plasticity in accordance with the Unified Soil Classification System (USCS) and ASTM D-2488 (Description and Identification of Soils-Visual/Manual Procedures). After classification, the engineering geologist grouped the various soil types into the major zones noted on the boring logs and subsurface profile in Appendix B. The group symbols for each soil type are indicated in parentheses following the soil descriptions on the boring logs. The stratification lines designating the interfaces between earth materials on the boring logs are approximate; in situ, the transitions may be gradual.

Classification and index property tests were performed on representative soil samples obtained from the test borings in order to aid in classifying soils according to the Unified Soil Classification System and to quantify and correlate engineering properties. Representative soil samples from the test borings were subjected to moisture content, gradation (percent passing the #200 sieve), and Atterberg Limits tests to aid in ascertaining pertinent engineering properties. The results from the laboratory testing were used to substantiate the visual classifications and to evaluate the soil’s pertinent engineering characteristics. The results of all the laboratory testing are included in Appendix C of this report. The soil samples will be retained in our laboratory for a period of 60 days, after which they will be discarded unless other instructions are received as to their disposition.

4.0 DESIGN RECOMMENDATIONS

4.1 BUILDING FOUNDATION DESIGN

General: Our design recommendations assume building subgrade preparation, Structural Fill compaction, and foundation subgrade preparation are successfully completed. Careful observation of all subgrades and foundation excavations should be made during construction to assure that materials on which foundations will bear are stable. We recommend the building foundation design use the following parameters.

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Table 4.1-1 Building Foundation Design Parameters

Design Parameter Column Footing Wall Footing

Net Allowable Bearing Pressure(1) 2,500 psf 2,500 psf

Acceptable Bearing Soil Material Structural Fill, Foundation

Excavation Backfill, or Stable Natural Soils

Structural Fill, Foundation Excavation Backfill, or Stable

Natural Soils

Minimum Width 24 inches 24 inches

Minimum Footing Embedment Depth (below finished exterior grade) (2) 24 inches 24 inches

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

Estimated Differential Settlement Less than ½ inch between columns

Less than ½ inch in 50 feet of wall

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, frost penetration requirements, and expansive soil concerns.

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

Removal of Unsuitable or Unstable Material: The proposed building footprint contains localized areas of existing FILL to an observed depth of 2 below existing grades. The FILL is considered undocumented and should be completely removed from below all foundations. Undercutting of the foundation excavations to depths of 0.5 to 2 feet and possibly more below the bottom of the footing should be anticipated. While it is the intention of this report to allow suitable and stable FILL to remain in place below floor slabs and pavements, the FILL suitability must be determined at the time of construction. All FILL, soft, loose, wet, or unsuitable and/or unstable soil should be undercut from below the foundations as the foundation excavations are made and be replaced with Foundation Excavation Backfill consisting of VDOT Size No. 57 Stone placed under the observation of the Geotechnical Engineer. The open-graded crushed stone (No. 57 Stone) can be readily placed with minimal compactive effort and will be less susceptible to deterioration from moisture intrusion. A representative of the Geotechnical Engineer should observe the foundation excavation work to help ascertain that stable, suitable soils have been exposed in the foundation excavations.

4.2 FLOOR SLAB DESIGN

Slab Subgrade Preparation: For the design and construction of all floor slabs-on-grade for the proposed building, the subgrade should be prepared in accordance with the recommendations contained in Section 5.1 of this report.

It is important that the floor slab subgrade be firm and stable before the placement of the granular base materials and concrete.

Subgrade Modulus: Provided the placement of Structural Fill and Porous Fill is per the recommendations discussed herein, the floor slab will be designed with a Modulus of Subgrade Reaction, Ks, of 160 psi per inch.

Slab Isolation: Ground-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, the slab should be designed with suitable reinforcement and load transfer devices to preclude overstressing of the slab.

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Underslab Moisture Protection: The building floor slabs-on-grade should be directly supported by a Porous Fill layer to facilitate the fine grading of the subgrade, provide more uniform bearing conditions, and help reduce the potential for the rise of water to the bottom of the slab (capillary action). For lightly loaded slabs-on-grade, the Porous Fill (underslab granular base) should consist of a minimum of 4 inches of VDOT Size No. 57 Stone or approved alternate.

Vapor Retarder: A polyethylene vapor retarder should be employed on top of the Porous Fill in heated areas to help provide moisture protection of finished slab surfaces. If a vapor retarder is considered to provide additional moisture protection, special attention should be given to the surface curing of the slabs to minimize uneven drying of the slabs and associated cracking and/or slab curling. The use of a blotter or cushion layer above the vapor retarder can also be considered for project specific reasons. Please refer to ACI 302.1R96 “Guide for Concrete Floor and Slab Construction” and ASTM E 1643 “Standard Practice for Installation of Water Vapor Retarders Used in Contact with Earth or Granular Fill Under Concrete Slabs” for additional guidance on this issue.

Underslab Drainage: Based on the groundwater information and the proposed finished floor elevation, an underslab drainage system is not required for the building floor slabs-on-grade.

4.3 DRAINAGE CONSIDERATIONS

Positive drainage away from the proposed building and pavement structures is an essential element in reducing the adverse effects that water might have on the foundation soil’s bearing quality. Positive drainage should be provided around the perimeter of the building and pavement structures to reduce moisture infiltration into the foundation and/or subgrade soils. Landscaped areas adjacent to the buildings should be provided with a fall of least six inches for the first ten feet outward from the building. Gutters or roof drains should be employed on the building and their effluent discharged away from the buildings or into the storm sewer system.

4.4 SEISMIC DESIGN

Seismic Site Classification: The International Building Code (IBC) 2015 requires site classification for seismic design based on the upper 100 feet of a soil profile. Based upon our interpretation of the subsurface conditions and experience in the project area, the site is considered to have a Seismic Site Classification of “D”. If it would be beneficial to the project to improve the Site Class, ECS can conduct in-situ site testing, upon request.

4.5 SITE RETAINING WALL DESIGN

General: An approximately 215 linear foot site retaining wall with a maximum height of about 4± feet will be located in the northeast boundary of the site. Specific details regarding the construction of the wall were not known at the time of this report.

Net Allowable Soil Pressures: For rigid site retaining wall footings, an average net allowable soil pressure of 2,500 psf may be employed for foundation design provided the maximum pressure at the toe does not exceed 2,800 psf and the resultant of the soil pressure distribution passes through the center third of the footing cross section.

Lateral Pressures: Rigid site retaining walls should be designed to withstand the lateral earth pressures exerted by the retained earth. The "At Rest" (Ko) soil condition should be used in the wall design and evaluation for rigid walls. In the design of the rigid retaining wall structures, the following soil parameters can be utilized. These parameters assume that Sand or Gravel meeting the requirements recommended herein for Retaining Wall Backfill will comprise the backfill in the Backfill Zone. On-site excavated clay and silt soils are not suitable for this use. Increased lateral pressures generated by surcharge loads should be considered in the retaining wall design.

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Table 4.5-1 Rigid Site Retaining Wall Design Parameters (Retaining Wall Backfill as specified herein)

Soil Parameter Estimated Value Restrained Soil Coefficient of Earth Pressure at Rest (Ko) 0.40 Restrained Soil Moist Unit Weight (δ1) 120 pcf Restrained Soil Cohesion (C) 0 psf Restrained Soil Angle of Internal Friction (ø) 28o Foundation Soil Coefficient of Passive Earth Pressure (Kp) 2.70 Foundation Soil Coefficient of Active Earth Pressure (Ka) 0.36 Foundation Soil Moist Unit Weight (δ2) 115 pcf Sliding Friction Resistance Coefficient [Concrete on Soil] (µ): 0.35

Resistance to Sliding: Horizontal forces acting on the footings will be resisted by sliding friction resistance on the bottom of the footing and “Passive” resistance of soils against which the horizontal force acts. Friction resistance on the sides of the footings can also be considered to resist horizontal forces. “Active” earth pressures should be used to determine the side friction resistance. Because the sliding friction and passive and active earth pressure resistances are based on limit strength conditions, an appropriate factor of safety of at least 1.5 should be applied to the designs considering these resistances.

Backfill Zone: The Backfill Zone is considered that zone directly behind retaining walls extending a horizontal distance equal to the wall height behind the wall. Backfill used within the Backfill Zone must satisfy the requirements for Retaining Wall Backfill provided in this report. In this regard, Lean and Fat Clays (CL and CH) and Elastic Silts (MH) are not suitable for use as backfill in the Backfill Zone. Silty SAND (SM), Clayey SAND (SC) or clean Sand (SP) or Gravel (GP) with a minimum Angle of Internal Friction (ø) of 30o and containing a maximum 35% by dry weight fines would be suitable for use in the Backfill Zone. Most, but not all, of the soils available from cut areas of the site are expected to be suitable for use as Retaining Wall Backfill.

Retaining Wall Drainage: Retaining walls should be provided with foundation and wall drains to remove excess moisture from the wall backfill. This drainage system may consist of drain lines located above the retaining wall footings which discharge to a suitable outlet. These drain lines should consist of perforated pipe surrounded by a minimum of 6 inches of free-draining granular filter or by VDOT No. 57 Stone wrapped in filter fabric. A suitable wall drain product should be employed on the back face of the retaining walls. Examples of suitable wall drain materials include Enka Mat, Mira Drain, or Geotec Drains. The material should be placed in accordance with the manufacturer’s recommendations and should be hydraulically connected to the foundation and/or underslab slab drainage system, which in turn should be properly drained. To reduce moisture infiltration of the backfill materials, the top 18 inches of Retaining Wall Backfill should consist of a Clayey soil (SC or CL) or the backfill surface should be paved.

Retaining Wall Backfill Compaction: The fill placed adjacent to rigid concrete retaining walls should not be over-compacted. Backfill compacted behind rigid retaining walls and within the Backfill Zone should be compacted to a minimum of 95% of the maximum dry…