B08_Solicitation_(Attach_9_CORRECTED_Questions_Answers)_0002.pdf

QUESTIONS & ANSWERS

140P6224B0001 – Tyler Bend Sewer and Launch Renovation

1. Regarding the trees that are scheduled to be removed, can they be burned in place on the jobsite?

A. Response – No, trees will have to be taken offsite to be disposed.

2. Will the park allow the job superintendent to have a camper or 5th wheel to stay during construction so that he does not have to drive in everyday from the surrounding area?

A. Response - Superintendent can utilize the campground host site during late fall and winter months until the campground host site is needed after opening March 15.

3. Will the government please provide the CAD drawings of the contract drawings?

A. Response – A link to the CAD files could not be provided in a reasonable timeframe.

4. Did a geotechnical engineer conduct a boring log to determine if there is rock beneath the area for the new asphalt road? If so, will the government provide the contractors with the boring log?

A. Response - Geotech report attached.

5. Please specify the depth of the existing lift station that needs to be demolished around Comfort

Station #2.

A. Response – The lift station is approximately 10ft deep from grade.

6. Will the government specify the electrical material required for the direct buried conduit around

Comfort Station #1?

A. Response - Per note 4. On Sheet E3 all conduit shall be Schedule 40 PVC with PVC Coated

RGS Riser to grade. Further details on the conduit requirements are listed in the Division 26 specifications sections. Contractor should review all of these sections for further detailed requirements on conduits/boxes/etc.

7. On page E4, in detail 2, some buried conduits are specified for communication (telephone, data, installations). Please confirm if communication is part of this project.

A. Response - The only communications/control cables in the project will be between the lift station and control panel. Per the note on plan sheet E3 however any direct buried conduits shall have a spare 1” conduit installed alongside for future use.

8. Please specify which type of armorflex block to be used at the ramp. i.e. open cell block, closed cell block, tapered open cell block, block and a half block.

A. Response - Per the details on sheet C12 the block shall be armorflex 50 Block & Half.

9. If open cell block is chosen, what should the voids be filled with?

A. Response - Voids shall be filled with native sand/aggregate from adjacent grading operations and cutoff wall removal. Mat seams or openings between mats greater than two (2) inches will be backfilled with 4000 p.s.i. non-shrink grout or concrete.

10. What armorflex concrete block class is required?

A. Response - armorflex 50 Block & Half

11. What is the asphalt binder performance grade requirement?

A. Response - i.e. PG 67-22 Either 64-22 or 70-22 will be allowed.

12. Is there a hydrant on site (1.5” or larger) the contractor can use to get water for water trucks? If there is not an existing hydrant, can we tap into the existing line and install one for our temporary use?

A. Response – The park has holding tanks and other connections the contractor can utilize for water trucks.

13. Does the septic tank installation and connection to building require a contractor with a plumbers license, or can it be completed by a site contractor.

A. Response – The installation will need to be completed by a licensed installer.

14. Does the Government have specifications for the lift pump?

A. Response –

Submersible Grinder Pumps: Environment One SPD Grinder Pump or approved equal.

1. Operating conditions:

a. 15 GPM at 0 FT TDH.

b. 11 GPM at 92 FT TDH.

c. 7.8 GPM at 185 FT TDH.

2. Drive horsepower: 1 HP maximum, 1725 RPM, 240 V 60 HZ, 1 Phase

3. Progressive cavity with grinder head.

4. Mechanical seal: ceramic seat and carbon rotating surface.

5. Pump castings shall be cast iron, fully epoxy coated 8-10 MILS nominal dry thickness.

6. 60 Hz.

7. 120/240V, 1-phase.

8. Explosion proof, approved for Class 1 Division 1 Locations.

Section 33 32 23 – Package Sewage Pumping Station spec is included.

15. Will the upper parking area be available for use as a staging area for equipment and possibly a construction site trailer?

A. Response – Yes. Or use of the group site parking beside the site depending on the time of year.

16. Does the Government plan to shut the area down early as discussed?

A. Response - The pavilion area that shares the main parking area is rented through the end of

October. The area cannot be shut down completely. We can designate a portion of the parking area for a construction zone.

GEOTECHNICAL ENGINEERING REPORT

TYLER BEND NEW ROADWAY SECTION

TYLER BEND ROAD

HARRISON, ARKANSAS

COVER PAGE

Prepared for:

HDR

703 Main Street, Suite 200

Rapid City, South Dakota 57701

Prepared by:

• Geotechnical Services

• Environmental Services

• Material Testing Services

Springfield, MO 4168 W. Kearney Springfield, MO 65803

Call 417.864.6000 Fax 417.864.6004 www.ppimo.com

PROJECT NUMBER: 283756

June 27, 2023

GEOTECHNICAL & MATERIALS ENGINEERS

MATERIALS TESTING LABORATORIES

ENVIRONMENTAL SERVICES

4168 W. Kearney Street.

Springfield, MO 65803

Ph: (417) 864-6000 www.ppimo.com

10,000 Hwy 160 Walnut Shade, MO 65771

Ph: (417) 561-8395

3500 East 13th Street Joplin, MO 64801

Ph: (417) 624-2005

LETTER

June 27, 2023

HDR

703 Main Street, Suite 200 Rapid City, 57701

Attn: Mr. Chris Bailey, P.E.

Email: Christopher.bailey@hdrinc.com

RE: Geotechnical Engineering Report Tyler Bend New Roadway Section Tyler Bend Road Harrison, Arkansas PPI Project Number: 283756

Dear Mr. Bailey:

Attached, please find the report summarizing the results of the geotechnical investigation conducted for the proposed Tyler Bend New Roadway Section in Harrison, Arkansas. We appreciate this opportunity to be of service and if you have any questions, please don’t hesitate to contact this office.

PALMERTON & PARRISH, INC. PALMERTON & PARRISH, INC.

By: By:

Matthew Hedgespeth Brandon R. Parrish, P.E.

Geotechnical Engineer Vice-President

Submitted: One (1) Electronic .pdf Copy

BRP/TLA/MLH

June 27, 2023 http://www.ppimo.com/ mailto:Christopher.bailey@hdrinc.com i

TABLE OF CONTENTS

TABLE OF CONTENTS

1.0 Introduction

2.0 Project Description

3.0 Site Description

4.0 Subsurface Investigation

4.1 Subsurface Borings

4.2 Laboratory Testing

5.0 Site Geology

6.0 General Site Subsurface Conditions

6.1 Soils

6.2 Groundwater

7.0 Earthwork

7.1 Site Preparation

7.2 Topsoil

7.3 Soft Surficial Soils

7.4 Inclement Weather

7.5 Shallow Groundwater Considerations

7.6 Scarifying and Recompacting

7.7 Fill Material Types

7.7.1 Rock Fill

7.8 Compaction Requirements

7.9 Landscaping & Site Drainage

7.10 Earthwork Construction Considerations

7.11 Excavations

8.0 Pavement

8.1 Flexible Pavement

8.2 Rigid Pavement

8.3 Pavement Thickness

9.0 Construction Observation & Testing

10.0 Report Limitations

APPENDICES

Appendix I - Figure Appendix II - Boring Logs & Key To Symbols Appendix III - General Notes Appendix IV - Grain Size Analysis Appendix V - Important Information Regarding Your Geotechnical Report

EXECUTIVE SUMMARY

EXECUTIVE SUMMARY

A Geotechnical Investigation was performed for the Tyler Bend New Roadway Section located along Tyler Bend Road in Harrison, Arkansas. It is understood that a new roadway section will be constructed at the project site. Traffic loading was not provided but is assumed to be light to moderate. Cut and fill depths are anticipated to be between 3 to 5 feet across the subject site to provide finished subgrade elevations.

Based upon the information obtained from the borings drilled and subsequent laboratory testing, the site is suitable for the proposed new roadway section. Important geotechnical considerations for the project are summarized below. However, users of the information contained in the report must review the entire report for specific details pertinent to geotechnical design considerations.

Topsoil was noted in the subsurface exploration to depths between 3 to 8 inches below the ground surface. Due to the influence of vegetation and trees, this material should be stripped from construction areas and stockpiled for use in non-structural areas or removed from the site;

Moisture sensitive lean clays were noted near the surface of the subgrade exploration. These lean clay soils contained significant sand contents in Boring 2 and were soft to stiff in-situ. This material is generally stable in dry conditions but is sensitive to the addition of moisture and repeated traffic. Some over excavation and replacement or stabilization may be required of these soils, especially within the area of Boring 2 where it is not anticipated to pass a proof-roll; and

Palmerton & Parrish, Inc. should be retained for construction observation and construction materials testing. Close monitoring of subgrade preparation work is considered critical to achieve adequate pavement and subgrade performance.

GEOTECHNICAL ENGINEERING REPORT

TYLER BEND NEW ROADWAY SECTION

TYLER BEND ROAD

HARRISON, ARKANSAS

1.0 INTRODUCTION

This is the report of the Geotechnical Investigation performed for the proposed Tyler Bend

New Roadway Section located along Tyler Bend Road in Harrison, Arkansas. This investigation was authorized by a Subconsultant Agreement # 1000100078695 effective

September 16, 2022, and signed by Mr. Jason Kjenstad, P.E., representing HDR. The approximate site location is shown below:

The purpose of the Geotechnical Investigation was to provide information for foundation design and construction planning, and to aid in site development. Palmerton & Parrish

Inc.’s (PPI) scope of services included field and laboratory investigation of the subsurface conditions in the vicinity of the proposed project site, engineering analysis of the collected

Subject Site

Geotechnical Engineering Report

HDR

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 3 PPI Project No. 283756 data, development of recommendations for design and construction planning, and preparation of this engineering report.

2.0 PROJECT DESCRIPTION

Item Description Site Layout See Figure 1: Boring Location Plan Pavements New Asphalt or Portland Cement Concrete.

Grading Based on the existing site grading, the proposed new roadway is anticipated to have cut and/or fill depths of 3 to 5 feet.

3.0 SITE DESCRIPTION

Item Description Physical Location Tyler Bend Road in Harrison, Arkansas Latitude:

Longitude:

(± Center of Project Site)

35.989578° -92.764133°

Available Historic Aerial Photography

Based on Google Earth Historical Images, the site has been relatively unchanged since 1994 with the Tyler Bend parking area and road. A small trail and building are located within the vicinity of the borings.

Current Ground Cover Grass and tree covered areas.

Existing Topography The site slopes to the north and east.

Drainage Characteristics Fair

4.0 SUBSURFACE INVESTIGATION

Subsurface conditions were investigated through completion of two (2) subsurface borings and subsequent laboratory testing.

4.1 Subsurface Borings

Boring locations were selected and staked in the field by PPI using a site plan provided by the Client. Approximate boring locations are shown on Figure 1, Boring Location

Plan. The Arkansas One-Call System was notified prior to the investigation to assist in locating buried public utilities.

Logs of the borings showing descriptions of soil and rock units encountered, as well as results of field tests, laboratory tests and a “Key to Symbols” are presented in

Appendix II.

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 4 PPI Project No. 283756

Borings were drilled on May 25, 2023, using 4.5-inch O.D. continuous flight augers powered by a track-mounted drill-rig. Soil samples were collected at 2.5 -foot centers during drilling. Soil sample types included split spoon samples collected while performing the Standard Penetration Test (SPT) in general accordance with ASTM

D1586 and thin-walled Shelby tubes pushed hydraulically in advance of drilling in accordance with ASTM D1587. Please refer to Appendix III for general notes regarding boring logs and additional soil sampling information.

4.2 Laboratory Testing

Collected samples were sealed and transported to the laboratory for further evaluation and visual examination. Laboratory soil testing included the following:

Moisture Content (ASTM D2216);

Unconfined Compressive Strength (ASTM D2166);

Atterberg Limits (ASTM D4318);

Grain Size Analysis (ASTM D6913); and

Pocket Penetrometers.

Laboratory test results are shown on each boring log in Appendix II and are summarized in the following table. Grain Size Analysis results are presented in

Appendix IV and are also summarized in the following table.

Boring Depth (ft.)

Liquid Limit

(LL)

Plastic Limit

(PL)

Plasticity Index

(PI)

Moisture Content

%Passing No. 200 Sieve

Cohesion (psf)

Dry Unit Wt.

(pcf)

USCS

Symbol

1 3.0 27 12 15 16.2 - 2,075 115.8 CL

2 3.5 - - - 16.5 68 - - CL

5.0 SITE GEOLOGY

The general site is underlain at depth by the St. Joe Limestone Member of the Boone

Formation. The bedrock unit characteristically consists of mainly fine crystalline limestone and interbedded chert and minor shale layers. The site is also effected by the Buffalo

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 5 PPI Project No. 283756

River and likely influenced by young terrace and active channel alluvial deposits which consist of unconsolidated sand and gravel.

The upper surface of the limestone can be irregular due to the effects of differential vertical weathering and solution activity. Overburden soils in the site area typically consist of residual clays that are suspected of having developed through chemical and physical weathering of the underlying parent dolostone. The boundary between overburden soils and comparatively unweathered bedrock is usually abrupt.

6.0 GENERAL SITE SUBSURFACE CONDITIONS

Based upon subsurface conditions encountered within the borings drilled at the project site, generalized subsurface conditions are summarized below. Soil stratification lines on the boring logs indicate approximate boundary lines between different types of soil units based upon observations made during drilling. In-situ transitions between soil and some rock types are typically gradual.

6.1 Soils

Based on the results of the subsurface exploration, the subject site primarily consists of brown, lean clay (CL) soils. The surface of the site is covered in approximately 3 to 8 inches of topsoil containing roots from vegetation. Beneath the topsoil is a layer of brown lean clay (CL) extending to typical depths of 6 to 8 feet below the ground surface where it transitions into fat clay (CH). Variable amounts of sand and gravel were noted in the lean clay material. The fat clay layer extended to boring termination depths.

6.2 Groundwater

Shallow groundwater was not observed within the borings on the date drilled.

Groundwater levels should be expected to fluctuate with changes in site grading, precipitation, and regional groundwater levels. Groundwater may be encountered at shallower depths during wetter periods.

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 6 PPI Project No. 283756

7.0 EARTHWORK

7.1 Site Preparation

Grading plans for the proposed new roadway were not provided. Grading for the project site is anticipated to have between 3 and 5 feet of cut and/or fill to establish final grades. The initial phase of site preparation should include the steps listed below;

It is recommended that a representative from PPI be present during site preparation to help identify the conditions described below;

Stripping and removal of all topsoil and vegetation as described in Section 7.2;

Areas of lean clay may be sensitive to moisture and require over excavation and replacement or stabilization if exposed to rain, excessive moisture, or repeated traffic as described in Section 7.3;

All areas scheduled to receive new fill should be proof-rolled as described below.

Fill should not be placed on a frozen subgrade.

Proof-rolling consists essentially of rolling the ground surface with a loaded tandem axle dump truck or similar heavy rubber-tired construction equipment and noting any areas which rut or deflect during rolling. All soft subgrade areas identified during proof-rolling should be undercut and replaced with compacted fill as outlined below. Proof-rolling, undercutting, and replacement should be monitored by a qualified representative of the Geotechnical Engineer. The depth and areal extent of undercutting, if any, should be minimal but will be largely dependent upon the time of year and related soil moisture conditions. If construction is initiated during wetter spring or winter months, the requirement for undercutting soft surficial soils below normal topsoil stripping should be anticipated and reflected in contract documents. As previously mentioned, lean clays at the project site are moisture sensitive and may pose difficulties regarding subgrade stability and proper compaction.

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 7 PPI Project No. 283756

7.2 Topsoil

Topsoil was noted in the subsurface exploration to depths between 3 to 8 inches below the ground surface. Due to the influence of vegetation and trees, this material should be stripped from construction areas and stockpiled for use in non-structural areas or removed from the site. Large root systems, such as root balls from trees or any root over 6 inches in diameter should be included in the removal of topsoil from beneath pavements. Root systems may extend to depths deeper than those noted in the subsurface exploration. It should be noted that the use of the term topsoil within this report is for site construction and does not imply that the material is suitable for sale as topsoil.

7.3 Soft Surficial Soils

Areas of lean clay were noted near the surface in both borings. Generally, these materials may be stable during dry weather; however, these materials are anticipated to be sensitive to the addition of moisture. During wet seasons or rain events or when exposed to repeated traffic, the near surface lean clay soils may become unstable and require over excavation and replacement or stabilization. The amount of over excavation will be dependent upon conditions encountered during construction.

In addition, the surficial lean clay soils within the area of Boring 2 were noted to be soft in-situ to a depth of 5.5 ft. below the existing ground surface. These soils are not anticipated to pass a proof-roll and replacement or stabilization, i.e.

placement of a rock fill sub-base or geogrid reinforced aggregate baserock, should be anticipated within this area and possibly other areas not drilled.

7.4 Inclement Weather

If construction is initiated during wetter months, the requirement for undercutting soft surficial soils below normal site stripping should be anticipated and reflected in contract documents in areas where new construction is anticipated for the remodel.

Undercut depths on the order of 2 or more ft. are considered possible within the

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 8 PPI Project No. 283756 development area. The shallow lean clay subgrade at the site is known to significantly lose strength when saturated and disturbed by construction equipment. Further, material removed from undercuts may not be suitable for use as compacted fill due to high soil moisture if poor drying conditions (cool temperatures and/or frequent precipitation) occur during site grading. If the construction schedule will not permit delay for better drying conditions, the project budget should include an allowance for subgrade undercut and replacement soil material containing appreciable quantities of chert or sand and gravel from an off-site borrow area that meet the requirements above. As an alternate to select fill, rock fill subbase (4 to 6-inch top size stone) may be placed to improve subgrade stability.

7.5 Shallow Groundwater Considerations

Groundwater was not encountered during the subsurface exploration at the depths explored. As previously mentioned, water levels at the subject site should be anticipated to fluctuate with seasonal changes in moisture. Due to the close proximity to the Buffalo River the groundwater levels at the site will fluctulate with river water levels. Contractors should be prepared to encounter areas of shallow groundwater at the subject site.

7.6 Scarifying and Recompacting

Subgrade areas approved after proof-rolling should be scarified to a depth of at least

8 inches and soil moisture adjusted and compacted to comply with project specifications.

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 9 PPI Project No. 283756

7.7 Fill Material Types

Fill Type1 USCS Classification Acceptable Location for Placement

Low Volume Change (LVC) Engineered Fill2

Non-shaley CL5, GC &/or SC

(LL < 45%)

All locations and elevations

CL5 All locations and elevations On-Site Natural Soils

CH3 See Note 3 CL, SC, & GC All locations and elevations

Potential Borrow Material CL-CH & CH See Note 3

Rock Fill4 GW All locations and elevations

1. Controlled, compacted fill should consist of approved materials that are free of organic matter and debris and contain maximum rock size of 4 to 6 in. Frozen material should not be used and fill should not be placed on a frozen subgrade. A sample of each material type should be submitted to the Geotechnical Engineer for evaluation prior to its use.

2. Non-shaley, low plasticity cohesive soil or granular soil having at least 15% low plasticity fines.

3. CL-CH or CH clays with a Liquid Limit equal to or above 45% are considered suitable for use as controlled fill, only if the percentage of rock fragments exceeds 35% or if placed 2 feet below shallow foundations, pavements, or slab areas.

4. If rock fill will be utilized at the project site see Section 7.7.1.

5. Caution should be exercised when utilizing on-site lean clays as fill material. These soils are moisture sensitive and may not provide a stable subgrade even when properly compacted when soil moisture is above optimum.

7.7.1 Rock Fill

If rock is to be used as the primary filling medium, embankments should be constructed using rock having maximum dimensions in excess of 4 inches, but no greater than 8 inches. Rock material should be placed in horizontal layers having a thickness of approximately the maximum size of the larger rock comprising the lift, but not greater than 12 inches. Rocks or boulders too large to permit placing in a 12-inch-thick lift should be reduced in size as necessary to permit placement or be bladed over the edge of the fill and not used in the compacted fill. Rock fill should not be dumped into place but should be distributed in horizontal lifts by blading and dozing in such a manner as to ensure proper placement into final position in the embankment. Finer material including rock fines and limited soil fines should be worked into the rock voids during this blading operation. Excessive soil and rock fine particles preventing interlock of cobble and boulder sized rock should be prohibited. Rock fill should be consolidated by a minimum of three (3) passes of a large diameter self-propelled vibratory compactor. Terminal fill slopes

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 10 PPI Project No. 283756 using rock may be constructed 1.5 horizontal to 1 vertical for fill height of 15 feet or less. The testing of rock fill quality should include the requirements that a representative of the Geotechnical Engineer be present daily, but not necessarily continuously during the placement of the fill to observe the placement of rock fill in order to determine fill quality and to observe that the contractors work sequence is in compliance with this specification. Progress reports indicative of the quality of the fill should be made at regular intervals to the Owner. If improper placement procedures are observed during the placement of the fill the Geotechnical

Engineer should inform the Contractor, and no additional fill should be permitted on the affected area until the condition causing the low densities has been corrected and the fill has been reworked to obtain sufficient density.

7.8 Compaction Requirements

Item Description Subgrade Scarification Depth At least 8 inches

Fill Lift Thickness 8-inch (loose) Compaction Requirements1 95% Standard Proctor Density (ASTM D-698)

Moisture Content ± 2% optimum moisture for CL, SC, or GC soil types; or 0 to 4% above optimum for CL-CH or CH soil types

Recommended Testing Frequency One (1) Field Density (compaction) test for each

5,000 sq. ft. of fill within paving areas; and A minimum of three (3) tests per lift.

1. We recommend that engineered fill (including scarified compacted subgrade) be tested for moisture content and compaction during placement. Should the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved.

7.9 Landscaping & Site Drainage

Rapid, efficient runoff away from the pavement should be implemented to reduce the potential for large fluctuations in moisture within the subgrade soils. Ponding of surface water immediately adjacent to the pavements can significantly increase subgrade moisture and may result in undesirable subgrade movement. As previously mentioned, careful consideration should be given to the landscaping and drainage elements to be installed at the project site adjacent to pavement areas. Trees and

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 11 PPI Project No. 283756 some large bushes can draw significant moisture from the subgrade soils, resulting in shrinkage and subsequent pavement movement.

7.10 Earthwork Construction Considerations

Once grading and filling operations have been completed, the moisture within the subgrade should be maintained and soils not be allowed to dry and desiccate prior to construction of the pavement. Grading of the site should be performed in such a manner so that ponding of surface water on prepared subgrade or in excavations is avoided. During construction, if the prepared subgrade should become frozen, desiccated, saturated, or disturbed, the affected material should be scarified or removed, moisture conditioned and recompacted prior to pavement construction.

7.11 Excavations

Based upon the subsurface conditions encountered during this investigation, the on-site soils typically classify as Type C in accordance with OSHA regulations. Temporary excavations in soils classifying as Type C with a total height of less than 20 feet should be cut no steeper than 1.5H:1V in accordance with OSHA guidelines. Deep excavations are not anticipated for this Project. Confirmation of soil classification during construction, as well as construction safety (including shoring, if required), is the responsibility of the contractor.

8.0 PAVEMENT

Pavement subgrades should be prepared in accordance with Section 7 of this report.

Accordingly, removal and replacement with select fill material or installation of subgrade stabilization should be anticipated to achieve a stable subgrade. It is anticipated that any new pavements associated with this project will be constructed of either an asphaltic concrete wearing surface placed over a base or a rigid Portland Cement Concrete pavement over a granular base.

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 12 PPI Project No. 283756

8.1 Flexible Pavement

If asphaltic paving is selected, the aggregate base may be a granular compacted crushed gravel/stone with a gradation and quality conforming to the requirements of the Arkansas State Highway and Department of Transportation Department (AHTD), Standard Specification 303. The maximum lift thickness for the granular base is 4 in.

Granular base thicknesses in excess of 4 inches should be placed in multiple lifts with each lift being of approximately equal thickness. The granular base should be compacted to at least 100% of Standard Proctor Compaction (ASTM D-698).

Asphaltic concrete, both base and surface, should conform to the applicable requirements of AHTD Standard Specification 404. Asphaltic concrete should be compacted to 92 to 96% of Maximum Theoretical Gravity (ASTM D-2041). Substitution of an appropriate Superpave Mix Design can be used in place of the bituminous base.

All bituminous mix designs should have been prepared or verified within 6 months of the date of placement on the project.

All asphalt mixes should comply with the following density, gradation, oil content and volumetric requirements during laydown. However, all Owners, Developers and

Contractors should be aware that minor changes in conditions (environmental, materials or mechanical) during production can cause variations in the volumetric properties of an asphalt mix design. Volumetric properties which vary slightly from the requirements below should be reported to the producer to allow plant adjustments.

Asphalt mix properties which consistently vary appreciably from the requirements in the following table should be considered deficient. All bituminous mix designs should have been prepared or verified within six (6) months of the date of placement on this project and should recognize the tendency of the mineral aggregate to “fine up” in the mixer.

8.2 Rigid Pavement

If rigid concrete paving is selected a minimum 4-inch-thick granular base compacted to 100% of Standard Proctor should be placed on the prepared subgrade. The

Portland Cement Concrete mix should have a minimum 28-day compressive strength

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 13 PPI Project No. 283756 of 4000 pounds per square inch (psi). Concrete should be placed at a low slump (1 to

3 inches) and have an entrained air content of 5 to 7%. If an increased slump is desired, use of Super Plasticizer is recommended. The use of reinforcing fibers incorporated into the concrete mix for crack control is recommended.

8.3 Pavement Thickness

A pavement thickness would best be computed if traffic frequencies and wheel loadings were provided to us, but a typical pavement design for this type of facility would generally generate a Structural Number of 3.0 to 3.5 within heavy duty areas and 2.4 to 2.6 within light duty areas, depending on the subgrade conditions. Based upon the soil conditions encountered within the borings drilled,a California Bearing

Ratio (CBR) of 3.0 is considered approprirate at this site. However, some subgrade remediation or improvement should be anticipated to be required to achieve a CBR of 3.0 within the areas of soft subgrade observed. The following table presents corresponding typical flexible and rigid pavement thicknesses using the general Structural Numbers. The pavement thicknesses provided can be re-evaluated if a final grading plan, traffic frequencies and wheel loadings are provided, if desired.

Pavement Type

Anticipated Traffic Frequency

Asphaltic Surface

(in.)

Asphaltic Base (in.)

Concrete Thickness (in.)

Aggregate Base (in.)

Heavy Duty 3.0 4.0 - 6.0 Heavy Duty w/

Tensar TX5 Geogrid* 3.0 3.0 - 6.0

Light Duty 2.0 2.0 - 6.0 Flexible

Pavement

Light Duty w/ Tensar TX5 Geogrid* 3.0 - - 6.0

Heavy Duty - - 7.0 4.0Rigid Pavement Light Duty - - 5.0 4.0

*Geogrid to consist of Tensar TX5, installed below aggregate baserock section per manufacturer’s recommendations.

9.0 CONSTRUCTION OBSERVATION & TESTING

The construction process is an integral design component with respect to the geotechnical aspects of a project. Since geotechnical engineering is influenced by variable depositional and weathering processes and because we sample only a small

Tyler Bend New Roadway Section - Harrison, Arkansas

June 27, 2023 Page 14 PPI Project No. 283756 portion of the soils affecting the performance of the proposed roadway, unanticipated or changed conditions can be disclosed during grading. Proper geotechnical observation and testing during construction is imperative to allow the Geotechnical Engineer the opportunity to evaluate assumptions made during the design process. Therefore, we recommend that PPI be kept apprised of design modifications and construction schedule of the proposed project to observe compliance with the design concepts and geotechnical recommendations, and to allow design changes in the event that subsurface conditions or methods of construction differ from those assumed while completing this study. We recommend that during construction all earthwork be monitored by a representative of

PPI, including site preparation, placement of all engineered fill and trench backfill, and all roadway excavations as outlined below.

An experienced Geotechnical Engineer or Engineering Technician of PPI should observe the subgrade throughout the proposed project site immediately following stripping to evaluate the native clay, identify areas requiring undercutting, and evaluate the suitability of the exposed surface for fill placement;

An experienced Engineering Technician of PPI should monitor and test all fill placed within the pavement areas to determine whether the type of material, moisture content, and degree of compaction are within recommended limits;

The condition of the subgrade should be evaluated immediately prior to construction of the roadway to determine whether the moisture content and relative density of the subgrade soils are as recommended.

10.0 REPORT LIMITATIONS

This report has been prepared in accordance with generally accepted practices of other consultants undertaking similar studies at the same time and in the same geographical area. Palmerton & Parrish, Inc. observed that degree of care and skill generally exercised by other consultants under similar circumstances and conditions. Palmerton & Parrish’s findings and conclusions must be considered not as scientific certainties, but as opinions based on our professional judgment concerning the significance of the data gathered during the course of this investigation. Other than this, no warranty is implied or intended.

APPENDIX I - FIGURE

PALMERTON & PARRISH, INC. FIGURE 1

Date: May 31, 2023 Project Number: 283756 Boring Location Plan

Project: Tyler Bend - New Roadway Section Client: HDR

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Ty le r B en d- Su b\ Fi gu re s\ Bo rin g

Lo ca tio ns

P la n.

dw g

1" = 120'

LEGEND

Boring Location

SCALE

1 2

AutoCAD SHX Text GEOTECHNICAL AND MATERIALS ENGINEERS/MATERIALS TESTING LABORATORIES/ENVIRONMENTAL SERVICES

APPENDIX II - BORING LOGS & KEY TO SYMBOLS

1.5

1.5

SPT

ST

SPT

SPT

0.7 ft

6.0 ft

10.0 ft

C F

A

.5

O

.D

2-3-5 (8)

3-4-5 (9)

3-4-6 (10)

SURFACE ELEVATIONDATE STARTED 5/25/23 COMPLETED 5/25/23

DRILL RIG 2005 CME-55

HAMMER TYPE Auto

LOGGED BY MV CHECKED BY MH

DRILLER EP

AT END OF DRILLING

NOTES

GROUND WATER LEVELS

AT TIME OF DRILLING None

BENCHMARK EL.

D R

IL

LI

N G

M E

T H

O D

D E

P T

H (f t)

0.0

2.5

5.0

7.5

10.0

E

LE

V A

T

IO

N (f t)

S T

R A

T A

S Y

M B

O L

DRY UNIT WT (pcf) 20 40 60 80 100

N VALUE

20 40 60 80

SHEAR STRENGTH (ksf) 1 2 3 4

20 40 60 80

PL LLMC

P O

C K

E T

P E

N

(t sf

S A

M P

LE

T

Y P

E N

U M

B E

R

C O

R R

E C

T E

D B

LO

W

C O

U N

T S

(N V

A

LU

E

R E

C O

V E

R Y

(R

Q D

GEOTECHNICAL

BORING LOG

BORING NUMBER

PROJECT LOCATION Harrison, Arkansas

PROJECT NAME Tyler Bend - New Roadway SectionCLIENT HDR

PROJECT NO. 283756

B O

R

IN

G L

O G

P

P I -

P P

I S T

D T

E M

P

LA

T E

.G D

T

/2

/2

0:

\M A

IN

-S

E R

V E

R \N

E T

W O

R K

\S H

A R

E D

M

A S

T E

R P

R O

JE

C

T F

IL

E

\2

2\ A

R \H

\H D

R -2

6- B

U F

F T

Y

LE

R B

E N

D -S

U B

\B O

R

IN

G L

O G

S \B

O R

IN

G

L O

G S

.G P

J 4168 W. Kearney St.

Springfield, MO 65803 Telephone: 417-864-6000

TOPSOIL - Grass Covered (8")

LEAN CLAY, Trace Sand, Brown, Medium Stiff to Stiff, Moist (CL)

- Very Stiff Below 2.5'

FAT CLAY, Brown, Stiff, Moist (CH)

Bottom of borehole at 10.0 feet.

MATERIAL DESCRIPTION

Unified Soil Classification System

SPT

SPT

ST

SPT

0.3 ft

8.0 ft

10.0 ft

C F

A

.5

O

.D

1-2-2 (4)

2-1-2 (3)

3-5-6 (11)

SURFACE ELEVATIONDATE STARTED 5/25/23 COMPLETED 5/25/23

DRILL RIG 2005 CME-55

HAMMER TYPE Auto

LOGGED BY MV CHECKED BY MH

DRILLER EP

AT END OF DRILLING

NOTES

GROUND WATER LEVELS

AT TIME OF DRILLING None

BENCHMARK EL.

D R

IL

LI

N G

M E

T H

O D

D E

P T

H (f t)

0.0

2.5

5.0

7.5

10.0

E

LE

V A

T

IO

N (f t)

S T

R A

T A

S Y

M B

O L

DRY UNIT WT (pcf) 20 40 60 80 100

N VALUE

20 40 60 80

SHEAR STRENGTH (ksf) 1 2 3 4

20 40 60 80

PL LLMC

P O

C K

E T

P E

N

(t sf

S A

M P

LE

T

Y P

E N

U M

B E

R

C O

R R

E C

T E

D B

LO

W

C O

U N

T S

(N V

A

LU

E

R E

C O

V E

R Y

(R

Q D

GEOTECHNICAL

BORING LOG

BORING NUMBER

PROJECT LOCATION Harrison, Arkansas

PROJECT NAME Tyler Bend - New Roadway SectionCLIENT HDR

PROJECT NO. 283756

B O

R

IN

G L

O G

P

P I -

P P

I S T

D T

E M

P

LA

T E

.G D

T

/2

/2

0:

\M A

IN

-S

E R

V E

R \N

E T

W O

R K

\S H

A R

E D

M

A S

T E

R P

R O

JE

C

T F

IL

E

\2

2\ A

R \H

\H D

R -2

6- B

U F

F T

Y

LE

R B

E N

D -S

U B

\B O

R

IN

G L

O G

S \B

O R

IN

G

L O

G S

.G P

J 4168 W. Kearney St.

Springfield, MO 65803 Telephone: 417-864-6000

TOPSOIL - Grass Covered (3")

SANDY LEAN CLAY, Trace Gravel, Brown, Soft to Medium Stiff, Moist (CL)

FAT CLAY, Trace Sand, Brown, Stiff, Moist (CH)

Bottom of borehole at 10.0 feet.

MATERIAL DESCRIPTION

Unified Soil Classification System

PROJECT NAME Tyler Bend - New Roadway SectionCLIENT HDR

PROJECT NO. 283756

ABBREVIATIONS

TV

PID

UC

ppm

TORVANE

PHOTOIONIZATION DETECTOR

UNCONFINED COMPRESSION

PARTS PER MILLION

LIQUID LIMIT (%)

PLASTIC INDEX (%)

MOISTURE CONTENT (%)

DRY DENSITY (PCF)

NON PLASTIC

PERCENT PASSING NO. 200 SIEVE

POCKET PENETROMETER (TSF)

LL

PI

W

DD

NP

-200

PP

Standard Penetration Test

Shelby Tube

SAMPLER SYMBOLSLITHOLOGIC SYMBOLS

(Unified Soil Classification System)

CH: USCS High Plasticity Clay

CL: USCS Low Plasticity Clay

CLS: USCS Low Plasticity Sandy Clay

TOPSOIL: Topsoil

WELL CONSTRUCTION SYMBOLS

KEY TO SYMBOLS

Water Level at Time Drilling, or as Shown

Water Level After 24 Hours, or as Shown

Water Level at End of Drilling, or as Shown

PROJECT LOCATION Harrison, Arkansas

K E

Y T

O S

Y M

B O

LS

P P

I S T

D T

E M

P

LA

T E

.G D

T

/2

/2

6:

M A

IN

-S

E R

V E

R \N

E T

W O

R K

\S H

A R

E D

M

A S

T E

R P

R O

JE

C

T F

IL

E

\2

\A

R \H

\H D

R -2

-B

U F

F T

Y

LE

R B

E N

D -S

U B

\B O

R

IN

G L

O G

S \B

O R

IN

G

L O

G S

.G P

J 4168 W. Kearney St.

Springfield, MO 65803 Telephone: 417-864-6000

APPENDIX III - GENERAL NOTES

GENERAL NOTES

*Modified after Ref. ASTM D2487-93 & D2488-93 **Modified after Ref. Oregon DOT 1987 & FHWA 1997 ***Modified after Ref. AASHTO 1988, DM 7.1 1982, and Oregon DOT 1987

SOIL PROPERTIES & DESCRIPTIONS

COHESIVE SOILS

Unconfined Compressive Strength (Qu)

Pocket Penetrometer Strength N-ValueConsistency

(psf) (tsf) (blows/ft) Very Soft <500 <0.25 0-1

Soft 500-1000 0.25-0.50 2-4 Medium Stiff 1001-2000 0.50-1.00 5-8

Stiff 2001-4000 1.00-2.00 9-15 Very Stiff 4001-8000 2.00-4.00 16-30

Hard >8000 >4.00 31-60 Very Hard >60

Group Symbol

Group Name Plasticity Moisture

CL – Lean Clay Description Liquid Limit (LL) Descriptive Term Guide ML – Silt Lean <45% Dry No indication of waterOL – Organic Clay or Silt Lean to Fat 45-49%

CH – Fat Clay Moist Indication of water

MH – Elastic Silt Fat ≥50% Wet Visible waterOH – Organic Clay or Silt

PT – Peat CL-CH – Lean to Fat

Clay

Fine Grained Soil Sub Classification Percent (by weight) of Total Sample Terms: SILT, LEAN CLAY, FAT CLAY, ELASTIC SILT PRIMARY CONSTITUENT

>30-50] >15-30] – secondary coarse grained constituents 5-15]

Sandy, gravelly, abundant cobbles, abundant boulders with sand, with gravel, with cobbles, with boulders scattered sand, scattered gravel, scattered cobbles, scattered boulders a trace sand, a trace gravel, a few cobbles, a few boulders <5] The relationship of clay and silt constituents is based on plasticity and normally determined by performing index tests. Refined classifications are based on Atterberg Limits tests and the Plasticity Chart.

NON-COHESIVE (GRANULAR) SOILS

**GRAIN SIZE IDENTIFICATION

Name Size Limits Familiar Example

RELATIVE DENSITY N-VALUE MOISTURE CONDITION

Descriptive Term Guide

Very Loose Loose

Medium Dense Dense

Very Dense

0-4 5-10

11-24 25-50 ≥51

Dry Moist Wet

No indication of water Damp but no visible water Visible free water, usually soil is below water table.

Boulder Cobbles

Coarse Gravel Fine Gravel

Coarse Sand Medium Sand

Fine Sand* Fines

12 in. or more 3 in. to 12 in.

¾-in. to 3 in.

No. 4 sieve to ¾-in.

No. 10 sieve to No. 4 sieve No. 40 sieve to No. 10 sieve

No. 200 sieve to No. 40 sieve Less than No. 200 sieve

Larger than basketball Grapefruit

Orange or lemon Grape or pea

Rock salt Sugar, table salt Powdered sugar

*Particles finer than fine sand cannot be discerned with the naked eye at a distance of 8 inches.

Coarse Grained Soil Sub Classification Percent (by weight) of Total Sample Terms: GRAVEL, SAND, COBBLES, BOULDERS PRIMARY CONSTITUENT

>30-50] >15-30] – secondary coarse grained constituents 5-15] <5]

Sandy, gravelly, abundant cobbles, abundant boulders with gravel, with sand, with cobbles, with boulders scattered gravel, scattered sand, scattered cobbles, scattered boulders a trace gravel, a trace sand, a few cobbles, a few boulders

Silty (MH & ML)*, clayey (CL & CH)* <15 ] (with silt, with clay)* 5-15 ] – secondary fine grained constituents (trace silt, trace clay)* <5 ] *Index tests and/or plasticity tests are performed to determine whether the term “silt” or “clay” is used.

GENERAL NOTES

*Modified after Ref. ASTM D2487-93 & D2488-93 **Modified after Ref. Oregon DOT 1987 & FHWA 1997 ***Modified after Ref. AASHTO 1988, DM 7.1 1982, and Oregon DOT 1987

BEDROCK PROPERTIES & DESCRIPTIONS

ROCK QUALITY DESIGNATION (RQD) SCALE OF RELATIVE ROCK HARDNESS

Description of Rock Quality *RQD (%)

Very Poor < 25 Poor 25-50

Term Field Identification

Approx.

Unconfined

Compressive Strength (tsf)

Fair 50-75 Extremely Soft Can be indented by thumbnail 2.6-10 Good 75-90 Very Soft Can be peeled by pocket knife 10-50

Excellent 90-100 Soft Can be peeled with difficulty by pocket knife 50-260 Medium Hard Can be grooved 2 mm deep by firm pressure of knife 260-520

Moderately Hard Requires one hammer blow to fracture 520-1040 Hard Can be scratched with knife or pick only with difficulty 1040-2610

Very Hard Cannot be scratched by knife or sharp pick >2610

*RQD is defined as the total length of sound core pieces 4 in. or greater in length, expressed as a percentage of the total length cored. RQD provides an indication of the integrity of the rock mass and relative extent of seams and bedding planes.

DEGREE OF WEATHERING . GRAIN SIZE (TYPICALLY FOR SEDIMENTARY ROCKS)

Description Diameter

(mm) Field IdentificationSlightly

Weathered Rock generally fresh, joints stained and discoloration extends into rock up to 25mm (1 in), open joints may contain clay, core rings under hammer impact. Very Coarse Grained >4.76

Coarse Grained 2.0-4.76 Individual grains can easily be distinguished by eye.

Weathered Rock mass is decomposed 50% or less, significant portions of rock show discoloration and weathering effects, cores cannot be broken by hand or scraped by knife. Medium Grained 0.42-2.0 Individual grains can be distinguished by eye.

Fine Grained 0.074-0.42 Individual grains can be distinguished by eye with difficulty.

Highly Weathered

Rock mass is more than 50% decomposed, complete discoloration of rock fabric, core may be extremely broken and gives clunk sound when struck by hammer, may be shaved with a knife.

Very Fine Grained <0.074 Individual grains cannot be distinguished by unaided eye.

VOIDS BEDDING THCKNESS

Pit Voids barely seen with the naked eye to 6mm *1/4-inch) Very Thick Bedded > 3’ Thick

Vug Voids 6 to 50mm (1/4 to 2 inches) in diameter Thick Bedded 1’ to 3’ Thick Cavity 50 to 6000mm (2 to 24 inches) in diameter Medium Bedded 4” to 1’ Thick Cave > 600mm Thin Bedded 1-1/4” to 4” Thick

Very Thin Bedded ½” to 1-1/4” Thick Thickly Laminated 1/8” to ½” Thick Thinly Laminated 1/8” or less (paper thin)

DRILLING NOTES

Drilling & Sampling Symbols

NQ – Rock Core (2-inch diameter) CFA- Continuous Flight (Solid Stem) Auger WB – Wash Bore or Mud Rotary HQ – Rock Core (3-inch diameter) SS – Split Spoon Sampler TP – Test Pit

HSA – Hollow Stem Auger ST – Shelby Tube HA – Hand Auger Soil Sample Types

Shelby Tube Samples: Relatively undisturbed soil samples were obtained from the borings using thin wall (Shelby) tube samplers pushed hydraulically into the soil in advance of drilling. This sampling, which is considered to be undisturbed, was performed in accordance with the requirements of ASTM D 1587. This type of sample is considered best for the testing of "in-situ" soil properties such as natural density and strength characteristics. The use of this sampling method is basically restricted to soil containing little to no chert fragments and to softer shale deposits.

Split Spoon Samples: The Standard Penetration Test is conducted in conjunction with the split-barrel sampling procedure. The “N” value corresponds to the number of blows required to drive the last 1 foot of an 18-inch long, 2-inch O.D. split-barrel sampler with a 140 lb. hammer falling a distance of 30 inches.

The Standard Penetration Test is carried out according to ASTM D-1586.

Water Level Measurements Water levels indicated on the boring logs are levels measured in the borings at the times indicated. In permeable materials, the indicated levels may reflect the location of groundwater. In low permeability soils, shallow groundwater may indicate a perched condition. Caution is merited when interpreting short-term water level readings from open bore holes. Accurate water levels are best determined from piezometers.

Automatic Hammer Palmerton and Parrish, Inc.’s CME’s are equipped with automatic hammers. The conventional method used to obtain disturbed soil samples used a safety hammer operated by company personnel with a cat head and rope. However, use of an automatic hammer allows a greater mechanical efficiency to be achieved in the field while performing a Standard Penetration resistance test based upon automatic hammer efficiencies calibrated using dynamic testing techniques.

APPENDIX IV - GRAIN SIZE ANALYSIS

0.0010.010.1110100

PI Cc CuLL PL

GRAIN SIZE DISTRIBUTION

COBBLES

GRAVEL

67.725

SAND

GRAIN SIZE IN MILLIMETERS

coarse fine

SANDY LEAN CLAY(CL)

Classification

D100 D60 D30 D10 %Gravel coarse

SILT OR CLAY

finemedium

3.5

%Sand %Silt %Clay

4.7 27.6

BOREHOLE DEPTH

BOREHOLE DEPTH

3 100

24 16 30

1 2006 10 501/2

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

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

3.5

P E

R C

E N

T F

IN

E

R B

Y W

E

IG

H T

PROJECT LOCATION Harrison, Arkansas

PROJECT NAME Tyler Bend - New Roadway SectionCLIENT HDR

PROJECT NO. 283756

G R

A

IN

S

IZ

E

P P

I S T

D T

E M

P

LA

T E

.G D

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/2

7/

:2

\\M

A

IN

-S E

R V

E R

\N E

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K \S

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D

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C T

F

IL

E \2

\A R

\H \H

D R

-2

6-

B U

F F

T Y

LE

R

B E

N D

-S U

B \B

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G

L O

G S

\B O

R

IN

G L

O G

S .G

P J

4168 W. Kearney St.

Springfield, MO 65803 Telephone: 417-864-6000

APPENDIX V - IMPORTANT INFORMATION REGARDING YOUR GEOTECHNICAL

REPORT