Amendment 0001 - AR ERFO FS 2020-1(1).pdf

(x)

693C7325B000010 x x

1 copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted ; or (c) By separate letter or electronic communication which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGEMENT TO BE

RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR

OFFER. If by virtue of this amendment you desire to change an offer already submitted , such change may be made by letter or electronic communication, provided each letter or electronic communication makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

x

ASHBURN VA 20147

ATTN: Construction

693C73

SUITE E2-3-300

QUANTUM PARK, 22001 LOUDOUN COUNTY PKWY

EASTERN FEDERAL LANDS HIGHWAY DIVISION

FEDERAL HIGHWAY ADMINISTRATION

ASHBURN VA 20147

ATTN: Acquisitions

693C73

SUITE E2-3-300

QUANTUM PARK, 22001 LOUDOUN COUNTY PKWY

EASTERN FEDERAL LANDS HIGHWAY DIVISION

FEDERAL HIGHWAY ADMINISTRATION

See Block 1406/11/20250001

13. THIS ITEM ONLY APPLIES TO MODIFICATION OF CONTRACTS/ORDERS. IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

12. ACCOUNTING AND APPROPRIATION DATA (If required) is not extended.is extended, Items 8 and 15, and returning

Offers must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended , by one of the following methods: (a) By completing

The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offers

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

FACILITY CODE CODE

10B. DATED (SEE ITEM 13)

10A. MODIFICATION OF CONTRACT/ORDER NO.

9B. DATED (SEE ITEM 11)

9A. AMENDMENT OF SOLICITATION NO.

CODE

8. NAME AND ADDRESS OF CONTRACTOR (No., street, county, State and ZIP Code)

7. ADMINISTERED BY (If other than Item 6)CODE 6. ISSUED BY

PAGE OF PAGES

4. REQUISITION/PURCHASE REQ. NO.3. EFFECTIVE DATE2. AMENDMENT/MODIFICATION NO. 5. PROJECT NO. (If applicable)

1. CONTRACT ID CODE

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

05/27/2025

CHECK ONE A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE CONTRACT

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority) appropriation data, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(b).

E. IMPORTANT: Contractor is not is required to sign this document and return __________________ copies to the issuing office.

ORDER NO. IN ITEM 10A.

14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible.)

Project AR ERFO FS 2020-1(1)

The purpose of this Amendment is to:

1) Provide a summary of responses to questions/clarifications asked by interested bidders.

2) Provide the Soils and Foundation Report.

The bid opening date of Tuesday, July 1, 2025, at 2:00 p.m. EDT remains unchanged.

16A. NAME AND TITLE OF CONTRACTING OFFICER (Type or print)15A. NAME AND TITLE OF SIGNER (Type or print)

15C. DATE SIGNED 16B. UNITED STATES OF AMERICA 15B. CONTRACTOR/OFFEROR 16C. DATE SIGNED

(Signature of person authorized to sign) (Signature of Contracting Officer)

STANDARD FORM 30 (REV. 11/2016)

Prescribed by GSA FAR (48 CFR) 53.243

Previous edition unusable

Except as provided herein, all terms and conditions of the document referenced in Item 9 A or 10A, as heretofore changed, remains unchanged and in full force and effect .

Amendment 0001

Info Page 1 of 2

Amendment No. 0001

Project AR ERFO FS 2020-1(1)

Ozark National Forest

Solicitation No. 693C73- 25-B-000010

The purpose of this Amendment is to:

1) Provide a summary of responses to questions/clarifications asked by interested bidders.

2) Provide the Soils and Foundation Report.

The bid opening date of Tuesday, July 1, 2025, at 2:00 p.m. EDT remains unchanged.

1. Do you have boring logs for this job?

Response: Soil boring information is available in Soils and Foundations Report, Report No. 04-23, Landslide Repair at Morgan Mountain Road (NFSR 1504). The

Soils and Foundations Report will be provided with this Amendment.

2. The access to the job will be extremely difficult to track equipment to the jobsite and to get dump trucks to the location. Will there be an adjustment to the contract time due to the difficult routes to get to the job?

Response: The Contractor may request time extensions according to Subsection

108.03.

3. Will the Forest Service be responsible for maintaining the dirt roads not inside the jobsite construction limits during construction and after construction, as we will be hauling a substantial amount of material into and out of the jobsite?

Response: The United States Forest Service (FS) will be responsible for maintaining

FS-owned roads outside the project limits.

4. What will be the actions if the landslide begins to move when we begin construction?

Response: The Contractor is responsible for notifying the Contracting Officer (CO) of changing site conditions. The CO will instruct the Contractor how to proceed.

5. Is this job for Veterans only?

Response: Per Block 2 of the Continuation of SF 1442, “This project is

RESTRICTED – Sealed bids will only be accepted from eligible certified Service-

Disabled Veteran-Owned Small Business concerns”. Companies that wish to be considered as prime contractors must be registered with the Small Business

Administration and certified as service-disabled veteran-owned small businesses prior to bid opening.

6. How far is the 3,000 CUYD select borrow from the job site?

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

Info Page 2 of 2

Response: The Contractor is responsible for locating material sources.

7. Where can we take the 25,500 excavated material to?

Response: A stated in Subsection 204.14, unsuitable or excess excavated material may be disposed of on site at the locations approved by the CO. The Contractor must dispose of material that cannot be placed on site legally off Government property. The Contractor is responsible for locating offsite disposal areas.

SOILS AND FOUNDATIONS REPORT

REPORT NO. 04-23

PROJECT: LANDSLIDE REPAIR AT MORGAN MOUNTAIN ROAD

(NFSR 1504)

AR ERFO FS 2020 - 1(1)

MADISON COUNTY, ARKANSAS

US DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

22001 LOUDON COUNTY PARKWAY

BUILDING E-2, SUITE 200

ASHBURN, VA 20147

FEBRUARY 2025

TABLE OF CONTENTS

1 INTRODUCTION

1.1 General

1.2 Project Description

2 GEOLOGIC SETTING

3 SUBSURFACE EXPLORATION PROGRAM

4 SUBSURFACE CONDITIONS

5 ANALYSIS AND RECOMMENDATIONS

6 DISCLAIMER/LIMITATIONS CLAUSE

REFERENCES

APPENDICES

Appendix A – Figures Appendix B – Geotechnical Data Report Appendix C – Slope Stability Analysis Results Appendix D – Selected Photographs

Note: Design changes subsequent to publication of this report and prior to the project’s advertisement will be documented by a memo attached after the title page.

PROJECT: AR ERFO FS 2020 - 1(1)

LANDSLIDE REPAIR OF MORGAN MOUNTAIN ROAD (NFSR 1504)

MADISON COUNTY, ARKANSAS

PAGE 3 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

SOILS AND FOUNDATIONS REPORT

REPORT NO. 04-23

PROJECT: LANDSLIDE REPAIR AT MORGAN MOUNTAIN ROAD

(NFSR 1504)

AR ERFO FS 2020 - 1(1)

MADISON COUNTY, ARKANSAS

1 INTRODUCTION

1.1 General

This report presents the results of the subsurface exploration, laboratory testing, geotechnical analysis, and recommendations for the the landslide repair at Morgan Mountain Road (NFSR 1504) in the Ozark National Forest in Madison County, Arkansas. The site location is shown on Figure 1, Appendix A.

1.2 Project Description

We understand that the landslide occurred in April to May 2020, following a series of heavy rain events.

Our field observations indicated that, at some sections, the road was displaced approximately 30 feet horizontally and 12 feet vertically for a distance of approximately 650 feet. The work includes reconstructing a 14-wide, two-way, gravel road.

2 GEOLOGIC SETTING

Available geologic information indicates that site is located within the Ozark Region, part of the interior highlands which comprises the north and western portions of the state. The rocks in the highland area are dominated by well-lithified sandstones, shales, limestones, and dolostones of Paleozoic age. The general Geologic Map of the site is shown on Figure 2 in Appendix A. Site Geology is addressed in more detail in the Geotechnical Data Report, Appendix B.

3 SUBSURFACE EXPLORATION PROGRAM

A subsurface exploration program consisting of drilling five (5) soil borings was conducted under the supervision of Schnabel Engineering, between November 28 and December 2, 2022. The Standard Penetration Test (SPT) was performed at selected depths in the borings. The borings were drilled to termination depths or auger refusal, whichever was encountered first. Rock coring was conducted in four

(4) of the five (5) test borings. Detailed information of the subsurface exploration, equipment used, borings location plan, and the boring logs are included in the Geotechnical Data Report, Appendix B.

MADISON COUNTY, ARKANSAS

PAGE 4 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

4 SUBSURFACE CONDITIONS

A brief description of the soil conditions encountered during the subsurface exploration is presented below.

The boring logs, soil profiles detailed subsurface soil and groundwater conditions encountered in the borings and results of laboratory testing are summarized on the boring logs and laboratory test results included in Appendix B.

The stratification lines designating the interfaces between soil types on the boring logs represent approximate boundaries. The transition between materials may be gradual. It should be noted that one or more of the units may be absent at specific locations. Subsurface conditions may vary between and beyond the boring locations. Also, cobbles and boulders may exist at different locations and depths.

STRATUM A (Colluvium)

A 16.5 feet thick layer of colluvium, that consisted primarily of silt, clayey gravel with sand, and a trace fat clay was encountered in the soil borings.

STRATUM B (Partially Weathered Rock)

Underneath the colluvium, partially weathered rock consisting of sandy silt, plastic silt, and lean clay was encountered to a depth of 30.1 feet.

STRATUM C (Shale)

Underlying the partially weathered rock, slightly weathered, intensely to moderately fractured Shale was encountered to the termination depth of 40.1 feet.

Groundwater

Groundwater was encountered in three of the five borings, BH22-01, BH22-02, and BH22-05 at depths of

22.0 ft, 5.0 ft, and 26.0 ft below existing site grades, respectively. It should be noted that fluctuations in the groundwater conditions due to seasonal weather changes should be anticipated.

MADISON COUNTY, ARKANSAS

PAGE 5 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

5 ANALYSIS AND RECOMMENDATIONS

5.1 Geotechnical Evaluation

Landslides occur as a result of unbalanced pressures along the sloping ground. The presence of water acts as a trigger mechanism by increasing the driving forces and/or reducing the shear strength of the in-situ materials. To mitigate slope stability problems, various approaches can be used. One approach is to reduce the driving forces and increasing shear strength. The shear strength can be increased by lowering the groundwater table which can be attained by improving the surface and subsurface drainage systems.

Another approach is increasing the resisting forces. Increasing the resisting forces can be achived by buttressing the slope, adding a retaining structure, or by reinforcing the slope.

5.2 Design Alternatives

Various alternatives were considered given their feasibility and effectiveness, site subsurface conditions, constructability, cost, and our experience with similar projects. A brief discussion of each alternative is presented below.

Alternative No. 1 – Gabion-faced Mechanically Stabilized Earth (MSE)

This alternative consists of re-establishing the roadway and stabilize the slope by constructiing a retaining wall with geosynthetic reinforced soil. MSE walls may have gabion baskets facing for ease of constructability.

Alternative No. 2 – Reinforced Soil Slope (RSS)

Reinforced soil slopes are constructed using common construction materials, and conventional equipment and techniques, providing an economical and durable structures. These type of walls are cost effective, self-draining, and can tolerate larger differential settlements compared to other repair alternatives and they can be more esthetically pleasant. The reinforcing can be achieved by placement of horizontal gyosynthetic or metal elements.

Alternative No. 3 – Anchored Soldier Pile Wall and Pre-cast Concrete Lagging

This alternative consists of re-establishing the roadway and stabilize the slope by constructing an anchored soldier pile wall and precast concrete lagging. This retaining wall system is composed of vertical steel H- Piles embeded into stiff or dense strata. Ground anchors are used to resist lateral forces and to enhance the external and global stability of the system. These wall systems are also self draining.

Alternative No. 4 – Large Diameter Drilled Shafts (Shear Pins)

Large diameter drilled shafts (shear pins) are installed at a determined interval to intercept the sliding plane and provide resistance. The drilled shafts include a wide flange column as a reinforcing core.

MADISON COUNTY, ARKANSAS

PAGE 6 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

5.3 Recommendations

Based on our observations during the site reconnaissance, the results of our subsurface exploration program, geotechnical analyses, and a discussion with our partner, it was concluded that a gabion faced Mechanically Stabilized Earth (MSE) wall is the preferred approach to repair the subject landslide.

We recommend that the MSE wall includes a subsurface drainage system composed of granular backfill and a perforated 6” diameter pipe. The drainage system should be surrounded by a filter fabric to prevent the migration of fines. The perforated 6” diameter pipe will drain subsurface water into a 6” diameter non-perforated outlet pipe located in the lowest point behind the wall. To keep wildlife out of the retaining wall drainage system a 1/4” mesh should be installed to cover the 6” diameter non-perforated pipe outlet.

5.4 Analyses

The slope stability anlayses of the proposed earth retaining system were conducted using limit equilibrium methodology, in general accordance with the design concepts and procedures presented in FHWA Publication FHWA-GEC 11 “Geotechnical Engineer Circular No. 11 – Design of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes” (2009), and following “AASHTO LRFD Bridge Design Specifications, 9th Ed.” (2020) design requirements. A uniform distributed live surcharge load was applied along the road to account for traffic loading following AASHTO-LRFD, 2020, Section 3.11.6.4 requirements. A summary of the soil engineering parameters assumed in the external, internal, and global stability analyses are presented in Table 1.

Table 1 - Summary of assumed engineering properties for analysis.

Material Type Unit Weight (pcf) Cohesion (psf) Internal Friction

Moved Colluvium 110 0 10

Partially Weathered Rock 115 4000 0

Shale 140 15000 0

Gabion Face 110 0 40

Granular Backfill 115 0 34

The selected load factors and combinations are presented in Table 2. The factors follow (AASHTO-LRFD, 2020). The resistance factors and Factors of Safety requirements for the analysis of MSE walls are presented in Table 3.

MADISON COUNTY, ARKANSAS

PAGE 7 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

Table 2 – Retaining wall load factors and combinations.

Load Combination EH EV ES LS EQ

Strength I (Max) 1.50 1.35 1.50 1.75 -

Strength I (Min) 0.90 1.00 0.75 1.75 -

Service I 1.00 1.00 1.00 1.00 -

Extreme Event I 1.00 1.00 1.00 1.00 or 0.50 1.00

Table 3 – Reinforced Soil Slope resistance factors.

Analysis Resistance Factor

Sliding Resistance

Overall/Global

Overall/Global Extreme Event I

The global/overall stability analysis computations were performed using the computer program Slide 2 by Rocscience, Inc. Copies of the computer output are included in Appendix C.

According to AASHTO 11.5.4.2, a seismic design shall not be considered mandatory for walls located in Seismic Zones 1 through 3, or for walls at Sites where the site adjusted peak ground acceleration is less than or equal to 0.4g, unless one or more of the following is true:

Liquefaction induced lateral spreading or slope failure, or seismically induced slope failure, due to the presence of sensitive clays that lose strength during the seismic shaking, may impact the stability of the wall for the design earthquake.

The wall supports another structure that is required, based on the applicable design code or specification for the supporting structure, to be designed for seismic loading and poor seismic performance of the wall could impact the seismic performance of that structure.

In addition, according to C11.5.4.2, paragraph 7, a seismic analysis should be considered mandatory if the wall is located in seismic zone 2 or higher, and if either of the following is greater than 30 feet:

The exposed wall height plus the average depth over the width of the wall of any soil surcharge present.

For tiered walls, the sum of the exposed height of all the tiers plus the average soil surcharge depth.

Based on the above listed criteria, we concluded that the retaining structure system selected does not require an external or internal seismic evaluation due to an adjusted PGA less than 0.4g, and the retaining structures are in Seismic Zone 1 to 3. However, an Extreme Event I global stability analysis is required for all sites.

For this analysis, an assumed allowable lateral deformation was established based on the flexible nature of the types of structure. See the evaluation calculations in Appendix C for details.

MADISON COUNTY, ARKANSAS

PAGE 8 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

A summary of the retaining structure parameters used in the analysis are presented in Tables 4 below.

Table 4 – Gabion Faced-MSE.

Approximate Reinforced Height (ft.)

Slope face inclination

Geogrid Spec.

Nominal Long- Term

Strength (lb/ft.)

Minimum geogrid length

(ft.)

Maximum geogrid vertical spacing

(ft.)

22 3.5V:1H Type IV 2,500 27 to 37 1.5

The proposed MSE wall satisfied the minimum static and Extreme Event I (seismic) global stability requirements with the following factors of safety.

Table 5 – Global/Overall Stability Calculated Factors of Safety.

Site Calculated Factor of Safety

Static Seismic

Sta. 105+50 1.636 1.356

Details of the global stability analyses are included in Appendix C.

MADISON COUNTY, ARKANSAS

PAGE 9 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

6 DISCLAIMER/LIMITATIONS CLAUSE

The subsurface explorations and tests described in this report have been conducted in accordance with standard practices and procedures (except as specifically noted). The results of these exploration and tests represent conditions at the specific locations, to the depths explored, and on the dates indicated. Subsurface conditions below the depths explored, between and beyond the boring locations may vary. The Geotechnical Evaluation and Recommendations Sections of this report include interpretations and recommendations developed by the Government in the process of preparing the design. These interpretations are not intended as a substitute for the personal investigation, independent interpretation, and judgment of the Contractor.

Prepared by:

Girmay Weldegiorgis, P.E.

Geotechnical Engineer

Reviewed by:

Mounir Abouzakhm, P.E.

Division Geotechnical Engineer

GIRMAY

HINTSA

WELDEGIORGIS

Digitally signed by

GIRMAY HINTSA

WELDEGIORGIS

Date: 2025.02.19 16:15:56 -05'00'

MOUNIR A

ABOUZAKHM

Digitally signed by

MOUNIR A ABOUZAKHM

Date: 2025.02.20 06:15:40 -05'00'

P ROJECT: AR ERFO FS 2020 - 1(1)

MADISON COUNTY, ARKANSAS

PAGE 10 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

REFERENCES

AASHTO LRFD Bridge Design Specifications, 2020, 9th Ed., Washington, D.C. American Association of State Highway and Transportation officials.

FHWA. (2014). Standard Specifications for Construction of Roads and Bridges on Federal Highway Projects (FP-14). US Department of Transportation. Washington D.C.: US Department of Transportation.

FHWA. (2015). Strength Characterization of Open-Graded Aggregates for Structural Backfills - FHWA-HRT-15-034. McLean: FHWA.

FHWA (2009) FHWA-NHI-10-024 & -025, “Geotechnical Engineer Circular No. 11 – Design of Mechanically Stabilized Earth Walls and Reinforced Soil Slopes”. Washington DC

P ROJECT: AR ERFO FS 2020 - 1(1)

MADISON COUNTY, ARKANSAS

PAGE 11 DEPARTMENT OF TRANSPORTATION

FEDERAL HIGHWAY ADMINISTRATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

APPENDICES

DEPARTMENT OF TRANSPORTATION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

APPENDIX A – FIGURES

SHEET

NO. PROJECT TOTAL

SHEETS

STATEREG

AR ERFO FS 2020 -

1(1)AR

FIGURE 1

SITE LOCATION MAP

U.S. DEPARTMENT OF TRANSPORTATION

FEDERAL LANDS HIGHWAY DIVISION

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VIRGINIA

Project : AR ERFO FS 2021 - 1(1)

Source:

USGS Arkansas geologic map data: https://mrdata.usgs.gov/geology/state/state.php?state=AR

Arkansas Geological Survey; https://www.geology.arkansas.gov/maps-and-data/geologic-maps.html

AR

FIGURE 2

GEOLOGIC MAP

U.S. DEPARTMENT OF TRANSPORTATION REG

FEDERAL LANDS HIGHWAY DIVISION

STATE TOTAL

SHEETS

EASTERN FEDERAL LANDS HIGHWAY DIVISION AR ERFO FS 2020 -

1(1)

SHEET

NO. PROJECT

ASHBURN, VIRGINIA

EASTERN FEDERAL LANDS HIGHWAY DIVISION

ASHBURN, VA

APPENDIX B – GEOTECHNICAL DATA REPORT

GEOTECHNICAL DATA REPORT

AR ERFO FS 2020-1(1)

Geotechnical Subsurface Exploration Services Morgan Mountain Road (NFSR 1504) in the Ozark National Forest, Madison County, Arkansas

Schnabel Reference No. 22190148.000 January 5, 2023

January 5, 2023

Mr. Robert A. Morris WSP USA, Inc.

13530 Dulles Technology Drive Suite 300 Herndon, Virginia 20171

Subject: Geotechnical Data Report

AR ERFO FS 2020-1(1)

Geotechnical Subsurface Exploration Services Morgan Mountain Road (NFSR 1504) in the Ozark National Forest, Madison County, Arkansas Schnabel Reference No.: 22190148.000

Dear Mr. Morris:

SCHNABEL ENGINEERING, LLC (Schnabel) is pleased to submit our geotechnical data report for this project. This report includes figures and appendices with relevant data collected for this study. This study was performed in accordance with our proposal dated October 12, 2022.

We appreciate the opportunity to be of service for this project. Please call us if you have any questions regarding this report.

Sincerely, SCHNABEL ENGINEERING, LLC

Kevin R. Morgan, PE Project Engineer

Richard H. Wargo, PE Principal

KRM:RHW

WSP USA, Inc

January 5, 2023 Page ii Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

GEOTECHNICAL DATA REPORT

AR ERFO FS 2020-1(1)

GEOTECHNICAL SUBSURFACE EXPLORATION SERVICES

MORGAN MOUNTAIN ROAD (NFSR 1504) IN THE OZARK NATIONAL FOREST

MADISON COUNTY, ARKANSAS

TABLE OF CONTENTS

1.0 SCOPE OF SERVICES

2.0 DESCRIPTION OF SITE

3.0 SUBSURFACE EXPLORATION

3.1 Test Borings

4.0 LABORATORY TESTING

4.1 Index Testing

4.2 Corrosivity Testing

4.3 Undisturbed Sampling – Consolidation and Strength Testing

4.4 Unconfined Compressive Strength Testing of Rock

5.0 SUBSURFACE CONDITIONS

5.1 Generalized Geology

5.2 Generalized Subsurface Stratigraphy

5.3 Groundwater

6.0 LIMITATIONS

LIST OF TABLES

Table 3.1: Test Boring Coordinates, Elevations, and Exploration Depths Table 4.2: Soil Corrosivity Table 5.3: Subsurface Stratigraphy

LIST OF FIGURES

Figure 1: Site Vicinity Map Figure 2: Boring Location Plan Figure 3: Subsurface Profile

APPENDICES

Appendix A: Subsurface Exploration Data Appendix B: Laboratory Test Data Appendix C: Photo Log Appendix D: USGS Geologic Map of Arkansas

January 5, 2023 Page 1 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

1.0 SCOPE OF SERVICES

Work Authorization dated November 1, 2022, authorized in accordance with the Master Services Agreement dated July 23, 2021, defines the scope of services for this project. The objective of this study was to evaluate the subsurface conditions at the site and provide a geotechnical data report containing the results of our study. This study was conducted under the supervision of a Professional Engineer registered in the state of Arkansas.

2.0 DESCRIPTION OF SITE

The project site is located on Morgan Mountain Road in the Ozark National Forest in Madison County, Arkansas. The site has currently undergone a landslide in which the gravel covered roadway shifted down slope towards the southwest. Two test borings were performed on either side of the existing land slide within the existing roadway and three within the roadway where the landslide has occurred. The approximate locations are shown on the boring location plan included as Figure 2. This report presents the results of our field investigation, test boring logs, soil profiles, laboratory testing results, and site maps.

3.0 SUBSURFACE EXPLORATION

Schnabel performed a subsurface exploration to identify the subsurface stratigraphy underlying the site and to evaluate the geotechnical properties of the materials encountered. This program consisted of Standard Penetration Testing (SPT) test borings and rock coring. Exploration methods used are discussed below. The appendices to this report contain the results of our exploration.

3.1 Test Borings

Schnabel’s subcontractor, GTS Inc. of Fayetteville Arkansas, drilled five test borings (one on either side of the landslide and three within the landslide) under our observation between November 28 and December 2, 2022. The Standard Penetration Test (SPT) was performed at selected depths in the borings. The borings were drilled to termination depths of up to 40.1 ft from the ground surface, or refusal.

Rock coring was conducted within four of the five test borings after approval from the COR.

The table below indicates the boring location coordinates, ground surface elevations, and the respective exploration depths.

Table 3.1: Test Boring Coordinates, Elevations, and Exploration Depths

Boring ID Northing Easting Ground Surface Elevation (ft)

Soil Boring Depth (ft)

Rock Coring Depth (ft)

BH22-01 528168.942 802912.832 1967.0 0.0 – 25.5 25.5 – 35.5

BH22-02 528056.399 802915.616 1957.9 0.0 – 16.5 16.5 – 26.5

BH22-03 527840.882 802998.787 1953.3 0.0 – 17.1 n/a

BH22-04 527761.037 803047.239 1951.6 0.0 – 14.6 14.6 – 24.6

BH22-05 527622.585 803199.699 1963.5 0.0 – 30.1 30.1 – 40.1

Note: Boring coordinates above are as drilled locations and may have been offset from the coordinate provided prior to drilling due to conflicts in the field. Borings were located in the field with a handheld Garmin GPS 60 unit.

Elevations were obtained from topographic map provided to us by EFL.

January 5, 2023 Page 2 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

A CME-550X all terrain rig was used to drill the borings. The borings were advanced by turning a continuous flight auger with a center opening of 3¼ inches. Cuttings were brought to the surface by the auger flights. Sampling was performed through the center opening in the hollow stem auger, by standard methods. No water was introduced into the boring using this procedure.

The Standard Penetration Test (SPT) was performed at selected depths in the borings following the standards of ASTM D1586 (AASHTO T206). The SPT N-values indicate the Standard Penetration Test resistances encountered in a particular layer as determined from the number of blows required to drive a 2-inch O.D., 1-3/8 inch I.D. sampling spoon one foot using a 140-pound hammer falling 30-inches. This test is conducted after seating the sampler six inches in the bottom of the hole according to ASTM D1586/AASHTO T206. The N-value is determined by adding the number of blows it takes to push the spoon the second and third 6-inch intervals together.

The SPT samples were obtained using a hydraulically driven automatic trip hammer (ATH). Most correlations with the SPT data are based on N-values collected with a safety hammer. Based on the information provided to us by our subcontractor GTS, Inc., the energy efficiency report of the site-specific CME-550X is 0.85. The hammer energy efficiency measurements were performed in 2022. Thus, the energy applied to the split-spoon sampler using the site-specific ATH is about 43 percent greater than that applied using the safety hammer, resulting in lower N-values. The hammer blows shown on the boring logs and cross sections are uncorrected for the higher energy.

Relative density values provided on the logs are based off uncorrected N-values. The following should be used to determine corrected values (N60); hammer energy efficiency of 0.85 and the following rod correction factors; 0.75 (lengths shorter than 13 ft), 0.85 (lengths between 13 and 20 ft), 0.95 (lengths between 20 to 33 ft), and 1.0 (lengths greater than 33 ft) to define soil’s relative density/consistency provided on the logs.

Once split spoons are removed from the augers, the split spoon is opened and the soil within is analyzed.

This analysis in the field includes visual classification, measuring the length of soil recovered, using a pocket penetrometer if the soil appears to have cohesion. The soil recovered is then placed into sealed bags which are labeled with the boring location, boring number, depth, date, and blow counts; sealed;

and brought back to Schnabel’s soil laboratory in Columbia, South Carolina.

Rock coring was conducted to evaluate the rock properties and quality, as well as obtain rock core specimens for further testing in the laboratory within each of the borings drilled. Rock coring depths were determined by the COR representative and confirmed prior to drilling while in the field.

Soils were classified in accordance with ASTM D2487 and AASHTO M145. The ASTM D2487 group symbols (e.g., SM) and AASHTO M145 group symbols (e.g., A-2-4), indicated on the boring logs, are based on laboratory testing of recovered soil samples and visual observations. The material description considers both visual and laboratory classifications, and with laboratory classifications having precedence over the visual method. Criteria for soil classification are given in Appendix A.

Appendix A includes specific observations, remarks, and logs for the borings; classification criteria; drilling methods; and sampling protocols. Figure 2, included at the end of this report, indicate the approximate test boring locations. We will forward untested samples to EFL’s laboratory in Sevierville, Tennessee.

January 5, 2023 Page 3 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

4.0 LABORATORY TESTING

Schnabel’s laboratory in Columbia, South Carolina, performed tests on selected samples obtained during the subsurface exploration. The testing aided in the classification of materials encountered in the subsurface exploration and provided data for use in the development of this report. The results of the laboratory tests are included in Appendix B and are summarized in Section 5.2 of this report. Selected test results are shown on the boring logs in Appendix A.

4.1 Index Testing

Schnabel’s laboratory in Columbia, South Carolina, performed index testing on soil samples collected as part of the exploration to provide soil classifications and to provide parameters for use with published correlations with soil properties. Index testing included performing natural moisture content (ASTM D2216 / AASHTO T265), Atterberg limits (ASTM D4318 / AASHTO T89 and T90), and gradation tests (ASTM D6913 / AASHTO T88) on the split spoon samples.

4.2 Corrosivity Testing

Tests for pH, sulfides, sulfates, chlorides, redox potential, and resistivity were conducted on soil samples representative of the upper on-site soils. The test results are presented in the table below:

Table 4.2: Soil Corrosivity

Parameter Boring No. Resistivity pH Redox Sulfide Sulfate Chloride

Test Method1 -

G187 / T288

G51 / T289

G200

EPA

SW9030B

EPA

SW9056A

EPA

SW9056A

Unit - ohm-cm - mV ppm ppm ppm

Value Depth (ft.)

BH22-01

3.5 – 5.5

24,800 4.55 252 BRL 28 BRL

Value Depth (ft.)

BH22-02

3.5 – 5.5

26,900 5.57 233 BRL 150 BRL

Value Depth (ft.)

BH22-05

3.5 – 5.5

28,300 6.41 230 BRL 29 BRL

*BRL: Below Reporting Limit

1) ASTM method followed by AASHTO method listed where applicable for Resistivity, pH, and Redox. EPA test methods listed for Sulfide, Sulfate, and Chloride.

These results are also presented in the Appendices, along with the various guidelines and criteria from DIPRA, AWWA, and ACI for evaluating soil corrosivity. Laboratory corrosivity testing indicates the corrosivity potential based on total cumulative soil corrosion values, per the various criteria for cast iron, steel, and concrete. Based on these test results, we anticipate the soil to have a mild corrosive potential for underground iron pipes, buried steel structures, reinforcing steel in buried concrete, and sulfate exposure in concrete. Various techniques can be utilized to mitigate corrosion in iron and steel, including the use of cathodic protection, coating of reinforcing steel (i.e. epoxy), thickening steel members. Sulfate

January 5, 2023 Page 4 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved exposure to concrete can be mitigated by using different Type cements, reducing water-cement ratio and/or increasing compressive strength of concrete mixes to reduce permeability.

4.3 Undisturbed Sampling – Consolidation and Strength Testing

Schnabel obtained one thin-walled steel tube (Shelby Tube) relatively undisturbed soil sample within the Fat Clay layer, from 6 to 8 feet below the existing ground surface, in boring BH22-02 to further evaluate these materials. The Shelby Tube only had a recovery of 13 inches, therefore only two points were able to be tested. Additional Shelby Tubes were attempted to be obtained while in the field, however the tubes crimped due to the stiffness of the clay layers. The Shelby Tube was tested for Consolidated Undrained Triaxial testing (ASTM D4767 / AASHTO T 297). The test results are presented in Appendix B.

4.4 Unconfined Compressive Strength Testing of Rock

Schnabel performed unconfined compressive strength (UCS) test per ASTM D7012 / AASHTO T229 on selected rock specimens representing Stratum C (Bedrock) to provide information regarding the strength of the rock encountered on site. The test results are shown on the boring logs in Appendix A and within the laboratory results in Appendix B.

5.0 SUBSURFACE CONDITIONS

5.1 Generalized Geology

As part of the subsurface exploration study, we reviewed available geologic data, the test borings performed at the project site, and information in our files. We characterized the following generalized subsurface stratigraphy based on the exploration and laboratory test data included in the appendices.

Based on this review, site is located within the Ozark Region, part of the interior highlands which comprises the north and western portions of the state. The rocks in the highland area are dominated by well-lithified sandstones, shales, limestones, and dolostones of Paleozoic age. A thin drape of younger unconsolidated clays, sands, and gravel, termed alluvium, is often found in valley floors and associated with the streams and rivers. The sedimentary deposits of the lowlands are mainly unconsolidated clay, sand and gravel of Quaternary age, poorly consolidated deposits of clay, sand, silt, limestone, and lignite of Tertiary age, and consolidated (to a limited extent) deposits of Cretaceous marl, chalk, limestone, sand and gravel. The rocks of the Ozarks tilt slightly to the south and have a dendritic drainage pattern. Since shales and siltstones erode faster than sandstones and limestones, the basic topography is flat-topped mountains with stepped flanks (Arkansas Geological Survey, 2010).

According to the United States Department of Agriculture (USDA) Natural Resources Conservation Service, the soils within the site consist predominantly of EME soils. These soils are part of the Enders- Mountainburg association and are located on steep slopes within the site. The Enders series consists of deep, well drained, very slowly permeable soils that formed in loamy and clayey residuum from shale, or interbedded shale and sandstone. These soils are on nearly level to moderately steep upland mountaintops and ridges and gently sloping to very steep mountain side slopes and foot slopes. Slopes range from 1 to 65 percent.

The soils at Morgan Mountain Road lie within the Atoka Formation consisting of colluvium deposits (map symbol - Pa).

The geological map of Arkansas is provided as Appendix D.

January 5, 2023 Page 5 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

Pa: Atoka Formation Figure 5.1: Geological Stratigraphy Classification Morgan Mountain Road

5.2 Generalized Subsurface Stratigraphy

We characterized the following generalized subsurface stratigraphy based on the subsurface exploration and laboratory test data included in the appendices. The boring logs, included within Appendix A, also display the stratum classifications.

January 5, 2023 Page 6 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

Table 5.2 :Subsurface Stratigraphy Material

Type Test Depth

(ft) Description

STRATUM A

(Colluvium)

From Ground Surface to depths of up to 16.5 ft.

Silt with Sand; brown and black (ML) (A-7-6) Silt; brown and black (ML) (A-7-6) Sandy Silt; grayish black or brown or black and gray (ML) (A-4) (A-7-5) Silty Gravel with Sand, light brown and grayish brown or orangish brown

(GM) (A-7-5)

Sandy Elastic Silt with Gravel, light brown and grayish brown (MH) (A-7-5) Clayey Gravel with Sand, brown or orangish brown or reddish brown (GC) (A-6) (A-7-6) Elastic Silt, grayish black or black and brown (MH) (A-7-6) (A-7-5) Fat Clay, light brown and grayish brown (CH) (A-7) (Visually Classified)

Moisture Content: 12.2 to 27.3 % Liquid Limit: 31 to 56 Plasticity Index: 7 to 22 % Passing No. 200 Sieve: 16.5 to 96.4 %

SPT N-Value: 0 to 29 bpf (BH22-05, 3.5 ft N-Value of 78 due to gravel) Relative Density: Fine Grained, Very Soft to Very Stiff

Coarse Grained, Loose to Medium Dense

STRATUM B

(Partially

Weathered Rock)

Below Stratum A to depths of up to 30.1 ft.

Sandy Silt; grayish black (ML) (A-4) Silt, brown (MH) (A-7-5) Lean Clay with Sand, black (CL) (A-7-6)

Moisture Content: 5.6 to 17.6 % Liquid Limit: 31 to 47 Plasticity Index: 7 to 18 % Passing No. 200 Sieve: 59.0 to 92.5 %

SPT N-Value: 50+ bpf Relative Density: Very Dense / Very Hard

STRATUM C

(Shale)

Below Stratum A or

B to termination depths of up to 40.1 ft.

Rock sampled as Weathered Shale Slightly Weathered, intensely to moderately fractured Compressive strength of 7,610 to 12,420 psi RQD: 24% to 92%, Very Poor to Excellent

January 5, 2023 Page 7 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

5.3 Groundwater

The test boring logs in Appendix A include groundwater observations obtained during our subsurface exploration. These data include depths to groundwater encountered during drilling and upon drilling completion.

Groundwater was observed in three of the five borings, BH22-01, BH22-02, and BH22-05 at a depth of

22.0 ft, 5.0 ft, and 26.0 ft below the ground surface during drilling, respectively.

The groundwater levels on the logs indicate our estimate of the hydrostatic water table at the time of our subsurface exploration. Some of the water levels recorded on the logs may represent zones where groundwater is perched above a low permeability layer. The presence and elevation of perched groundwater may vary significantly with variations in weather conditions. The final design should anticipate the fluctuation of the hydrostatic water table depending on variations in precipitation, surface runoff, stream levels, tidal variations, and similar factors.

6.0 LIMITATIONS

This report has been prepared to aid in the evaluation of this site and to assist in the design and construction of the project. It is intended for use concerning this specific project. We performed a subsurface investigation consisting of soil borings at discrete locations and potentially significant variations in subsurface features may not be observed in the data. Hence the subsurface data observed and recorded at the test boring locations may vary depending on actual site conditions.

We have endeavored to complete the services identified herein in a manner consistent with that level of care and skill ordinarily exercised by members of the profession currently practicing in the same locality and under similar conditions as this project. No other representation, express or implied, is included or intended, and no warranty or guarantee is included or intended in this report, or other instrument of service.

January 5, 2023 Schnabel Engineering, LLC Project 22190148.000 ©2023 All Rights Reserved

FIGURES

Figure 1: Site Vicinity Map Figure 2: Boring Location Plan Figure 3: Subsurface Profile

³

/1 6/

T hi s M ap w as C re at ed In

S ch na be l E ng in ee rin gs

S ite

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AR ERFO FS 2020-1(1)

PROJECT NO. 22190148.000

SITE VICINITY

MAP

FIGURE 1

MORGAN MOUNTAIN ROAD (NFSR 1504) IN THE OZARK

NATIONAL FOREST, MADISON COUNTY, ARKANSAS

Sources: Esri, HERE, Garmin, USGS, Intermap, INCREMENT P, NRCan, Esri Japan, METI, Esri China (Hong Kong), Esri Korea, Esri (Thailand), NGCC, (c) OpenStreetMap contributors, and the GIS User Community Esri, HERE, Garmin, (c) OpenStreetMap contributors Source: Esri, Maxar, Earthstar Geographics, and the GIS User Community Projection: WGS 1984 Web Mercator Auxiliary Sphere

© Schnabel Engineering, 2022. All Rights Reserved.

A

A'

1,960

1,955

1,950

1,945

1,940

1,935

GENERAL NOTES

lill:llm Cl-Ml

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�GC

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1. A DE SCRIPTION OF THE STRA TUM DE SIGNA TIONS IS PROVIDE D IN THE RE PORT TEXT.

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CLA SSIFICA TION.

3. A PLA N INDICA TING THE LOCA TION OF THE SUBSURFA CE PROFILE A LIGNME NT

BA SE LINE IS INCLUDE D AS FIGURE 2.

4. THIS DRA WING CONTA INS INTERPRETA TIONS OF TEST BORING DA TA .

5. SCA LIE A S SHOWIN.

6. BORINGS HA VE BE E N PR

J E CTE D O

TH

S

RFA CE PROFILIE.

550 600 650

1,970

1,965

1,960

1,955

1,950

1,945

1,940

1,935

1,930

1,925

1,920

250 300 350 400 450 500 550 600 DISTANCE ALONG BASELINE (ft)

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INTERPOL A TE D STRA TUM BOUNDARY

--?-- BE TWEE N BORINGS

A R ERFO FS 2020 - 1(1) DRAWN BY: DATE: SUB SURF ACE PROFILE

MORGAN MOUNTAIN ROA D (NFSR 150 4) l-__ c

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OZARK N A TIONAL FORREST C HECKED BY: SC ALE: PROJECT NO. 22190148.000

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APPENDIX A

SUBSURFACE EXPLORATION DATA

Subsurface Exploration Procedures General Notes for Subsurface Exploration Logs Identification of Soil – ASTM D2487 and AASHTO M145 Descriptive Criteria for Rock Core Logging Descriptive Terms of Rock Quality Supplemental Rock Descriptive Terms Boring Logs, BH22-01 through BH22-05 Rock Core Photos, BH22-01, BH22-02, BH22-04, and BH22-05

SUBSURFACE EXPLORATION PROCEDURES

Test Borings – Hollow Stem Augers

The borings are advanced by turning an auger with a center opening of 2¼ or 3¼ inches. A plug device blocks off the center opening while augers are advanced. Cuttings are brought to the surface by the auger flights. Sampling is performed through the center opening in the hollow stem auger by standard methods after removal of the plug. Usually, no water is introduced into the boring using this procedure.

Standard Penetration Test Results

The Standard Penetration Test (SPT) is performed in the borings at regular depth intervals to collect soil samples. The numbers in the Sampling Data column of the boring logs represent SPT results. Each number represents the blows needed to drive a 2-inch O.D., 1 -inch I.D. split-spoon sampler 6 inches, using a 140-pound hammer falling 30 inches. The sampler is typically driven a total of 18 or 24 inches.

The first 6 inches are considered a seating interval. The total of the number of blows for the second and third 6-inch intervals is the SPT “N-value.” The Standard Penetration Test is performed according to

ASTM D1586 (AASHTO T206).

The SPT samples were obtained using a hydraulically driven automatic trip hammer (ATH). Most correlations with SPT data are based on N-values collected with a safety hammer. The energy applied to the split-spoon sampler using the ATH is about 33 percent greater than that applied using the safety hammer, resulting in lower N-values. The hammer blows shown on the boring logs are uncorrected for the higher energy. However, we correct SPT N-values for the higher energy when using N-values in our analyses.

Soil Classification Criteria

The group symbols on the logs represent the Unified Soil Classification System Group Symbols (ASTM D2487) and AASHTO Soil Classification System Group Symbols (AASHTO M145) based on visual observation and limited laboratory testing of the samples. Criteria for visual identification of soil samples are included in this appendix. Some variation can be expected between samples visually classified and samples classified in the laboratory.

Partially weathered rock (PWR) is defined as residual material with SPT N-values between 100 blows per foot and refusal. Refusal is defined as an N-value of 50 blows for a penetration of one inch or less.

Rock Core Drilling

The drillers core drilled rock using special core bits set with carbide steel or diamond, depending upon the rock texture. The bit was fitted onto a double-tube, swivel-type core barrel in which an exterior tube and bit rotate, and an interior barrel remains stationary to receive the rock core. Drillers circulated water between the barrels and across the bit face to provide cooling and to flush away cuttings. The size of bits is indicated on individual boring logs.

The length of rock core recovered expressed as a percentage of the total length cored is shown on the logs. Rock Quality Designation (RQD) is also given for rock core drilled with NX-size core drilling equipment. RQD is defined as the total length of NX-size rock fragments recovered that are greater than 4 inches in length, discounting drilling breaks, expressed as a percentage of the total length cored. RQD is preferred to core recovery as a measure of engineering characteristics of rock.

Boring Locations

Boring locations were located by Schnabel Engineering as shown on Figure 2. Boring coordinates were provided by EFL and determined using a handheld Garmin GPS 60 unit and are indicated on the boring logs. Borings were offset from provided coordinates based on obstructions encountered in the field and new coordinates are provided within the report and logs. Elevations were determined using topographic maps provided to us by EFL. Locations and elevations should be considered no more accurate than the methods used to determine them.

GENERAL NOTES FOR

SUBSURFACE EXPLORATION LOGS

1. Numbers in sampling data column next to Standard Penetration Test (SPT) symbols indicate blows required to drive a 2-inch O.D., 1 -inch I.D. sampling spoon 6 inches using a 140 pound hammer falling 30 inches. The Standard Penetration Test (SPT) N value is the number of blows required to drive the sampler 12 inches, after a 6 inch seating interval. The Standard Penetration Test is performed in general accordance with ASTM D1586.

2. Visual classification of soil is in accordance with terminology set forth in “Identification of Soil.” The ASTM D2487 group symbols (e.g., CL) shown in the classification column are based on visual observations.

3. Estimated water levels indicated on the logs are only estimates from available data and may vary with precipitation, porosity of the soil, site topography, and other factors.

4. Refusal at the surface of rock, boulder, or other obstruction is defined as an SPT resistance of 100 blows for 2 inches or less of penetration.

5. The logs and related information depict subsurface conditions only at the specific locations and at the particular time when drilled or excavated. Soil conditions at other locations may differ from conditions occurring at these locations. Also, the passage of time may result in a change in the subsurface soil and water level conditions at the subsurface exploration location.

6. The stratification lines represent the approximate boundary between soil and rock types as obtained from the subsurface exploration. Some variation may also be expected vertically between samples taken. The soil profile, water level observations and penetration resistances presented on these logs have been made with reasonable care and accuracy and must be considered only an approximate representation of subsurface conditions to be encountered at the particular location.

7. Key to symbols and abbreviations:

S-1, SPT Sample No., Standard Penetration Test 5+10+1+4 Number of blows in each 6-inch increment

SH-1, SH Sample No., 2" or 3" Shelby Tube Sample Rec=24", 100% Recovery in inches, Percent Recovery

Run #1, CORE…