Roadway_Materials_Report_-_Eckert_Rd-Boise_River_-_Ridenbaugh_Canal_Bridges.pdf

Report Cover PageEckert Road, Boise River and Ridenbaugh Canal Bridges Roadway Materials Report

July 24, 2026 | Terracon Project No. 62235109B

Prepared for:

Local Highway Technical Assistance Council 3330 W. Grace Street Boise, Idaho 83703

Ada County Highway District

(ACHD)

5800 N Meeker Avenue Boise, Idaho 83713

Roadway Materials Report Eckert Road, Boise River and Ridenbaugh Canal Bridges | Boise, Idaho July 24, 2026 | Terracon Project No. 62235109B

Facilities | Environmental | Geotechnical | Materials i

Table of Contents

240.01 INTRODUCTION

240.02 VICINITY SKETCH

240.03 SOILS PROFILE / PAVEMENT CONDITION SURVEY

240.03.01 Soils Profile

240.03.02 Pavement Condition Survey

240.04 SOIL REPORT SUMMARY

240.04.02 Boring Logs and Test Pit Logs

240.05 TOTAL DESIGN PAVEMENT THICKNESS

240.06 SUB-SUBGRADING

240.07 GRADE POINTING

240.08 SPECIAL PLACEMENT

240.09 COMPACTION

240.10 SLOPE DESIGN SUMMARY

240.11 SLOPE DESIGN

240.12 EMBANKMENT FOUNDATION

240.13 SURFACE AND SUBSURFACE WATER

240.14 DRAINAGE

240.15 GEOSYNTHETICS

240.16 EXISTING ROADWAY MATERIAL

240.17 ROCK SUBGRADE

240.18 TOPSOIL

240.19 PIPE

240.20 RIPRAP

240.21 STAGED CONSTRUCTION

240.22 PAVEMENT DATA

240.22.01 Pavement Type and Pavement Smoothness

240.22.02 Typical Sections

240.23 BASE

240.23.02 Tack Coat

240.23.03 Prime Coat

240.24 SURFACE TREATMENT

240.25 PAVING

240.25.03 Class of HMA Recommendation

240.25.04 Performance Graded Binder Selection

240.26 SEAL

240.27 DUST ABATEMENT

240.28 AGGREGATE ESTIMATING DATA

240.29 AGGREGATE SOURCES

240.30 CURRENT SPECIFICATIONS AND MINIMUM TESTING

REQUIREMENTS

240.31 SPECIAL PROVISION ITEMS

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Facilities | Environmental | Geotechnical | Materials ii

240.32 REFERENCES

GENERAL COMMENTS

Appendices Appendix A

Site Location Exploration Plan Boring Logs Photography Log

Appendix B Grain Size Distribution Test Results R-Value & Expansion Pressure Test Results Corrosion Analysis Test Results

Appendix C Provided Traffic Information Traffic Calculations AASHTOWare Pavement ME Pavement Section Calculations Idaho R-Value Pavement Section Calculations LTPPBind Report Typical Pavement Section Dust Abatement Calculations

Appendix D Supporting Information for Borings Unified Soil Classification System (USCS)

Note: Blue Bold text in the report indicates a referenced section heading. The PDF version includes hyperlinks which direct the reader to that section and clicking on the logo will bring you back to the Table of Contents.

Facilities | Environmental | Geotechnical | Materials

Eckert Road, Boise River and Ridenbaugh Canal Bridges

Boise, Idaho Terracon Project No. 62235109B

July 24, 2026

240.01 INTRODUCTION

The project consists of reconstructing the approaches for the replacement of the Boise River and Ridenbaugh Canal Bridges and the new pedestrian undercrossing, and tie into the new proposed roundabout at the southern end of the project (intersection of Boise Avenue and Eckert Road, ACHD Project No. 325043) and the existing road at the north end of the project (near the intersection of Eckert Road and Millbrook Way). Eckert Road is currently a two-lane road with a multi-use pathway on the northwest side of Eckert Road. The speed limit varies from

We understand the new proposed roundabout will be a single-lane roundabout at the intersection of Boise Avenue and Eckert Road. Eckert Road will be widened to three-lanes (one travel lane each direction and a center-turn lane) between the roundabout and the Ridenbaugh Bridge. A 10-foot-wide multi-use pathway with a 4-foot buffer will be constructed on the northwest side of Eckert Road. A cast-in-place retaining wall is anticipated along Eckert Road between Boise Avenue and the Ridenbaugh Canal Bridge.

Additionally, MSE retaining walls are anticipated and the abutments of the Ridenbaugh Canal and Boise River Bridges and around the pedestrian undercrossing. We understand that this project is anticipated to be constructed in FY27 and be open in FY28. The project area includes approximately 440 feet of Eckert Road south of the Boise River and approximately 680 feet north of the Boise River. The elevation generally decreases towards the northeast (towards the Boise River).

This report addresses the new pavement recommendations for the Eckert Road and Boise Avenue intersection and roundabout in correspondence with the new alignment of Eckert Road over the Boise River. Stormwater management facilities are included as a part of the project.

The recommendations in this report are based the following publications:

■ ITD Materials Manual, 2020.

■ ITD Roadway Design Manual, 2013.

■ ITD Standard Specifications for Highway Construction, 2023, and the 2025

Supplemental Specifications.

Land use adjacent to the existing roadways generally consists of residential, commercial/industrial development, and recreational. The project limits consist primarily of asphaltic pavement. The vegetation in the proposed project area consisted primarily

July 24, 2026 | Terracon Project No. 62235109B

Facilities | Environmental | Geotechnical | Materials 2 of sparse vegetation. In the project vicinity, the ground surface slopes gently downward to the southwest.

240.02 VICINITY SKETCH

The project site location map is attached to this report in Appendix A. The approximate exploration locations are shown on the Exploration Plans presented in Appendix A.

240.03 SOILS PROFILE / PAVEMENT CONDITION

SURVEY

240.03.01 Soils Profile

Since the general alignment will remain relatively similar, a Soils Profile was not prepared for this project.

240.03.02 Pavement Condition Survey

A pavement condition survey was not performed for this report because the project will consist of new pavement construction.

240.04 SOIL REPORT SUMMARY

A Soils Report Summary was not prepared. Fill materials will come from approved Contractor furnished sources and primarily consist of granular borrow for embankment construction and Granular Subbase and Aggregate for Untreated Base for pavement section construction.

Geotechnical Characterization

Generally, the borings within Eckert Road encountered asphalt surfacing with a thickness of about 0.2 to 0.3 feet underlain by about 1½ to 16½ feet of granular fill. Granular fill generally consisted of medium dense to very dense sands and gravels with varying amounts cobbles and silt. Where fill was encountered outside Eckert Road, it consisted of silts, sands and gravels with varying amounts of clay to depths of about 6 to 10 feet.

The native subgrade soils observed in the borings typically consisted of loose to very dense native sand and gravel deposits with varying amounts of cobbles, boulders, silt and clay. The majority of the sand and gravel deposits were very dense.

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Groundwater was encountered in some explorations completed for this project and is discussed in 240.13 Surface and Subsurface Water.

240.04.02 Boring Logs and Test Pit Logs

Field Exploration

A total of 8 borings were drilled to depths of about 5.9 to 46½ feet for this report. Four additional near surface samples of the material around the two observed existing culverts were obtained. The quantity, general location and depth of the explorations are summarized in the following table.

Table 1: Exploration Boring Descriptions

Exploration Designation

Approximate Boring

Depth (feet) 1 Planned Location

B-1 5.9 Southwest of the Ridenbaugh Canal Bridge

B-2 91½ Between the Ridenbaugh Canal and Boise River

Bridges

B-6 91½ East of the Boise River Bridge

B-7 6½ Northeast of the Boise River Bridge

RW-13 30.7 Retaining Wall to the Southwest of the Ridenbaugh Canal BridgeRW-14 30.4

RW-15 31½ Retaining Walls northeast of the Boise River BridgeRW-16 46½

1. Approximate exploration depth below the existing ground surface at the time of exploration.

The approximate exploration locations are shown on the Exploration Plans presented in Appendix A. Individual boring logs are included in Appendix A.

Exploration Layout and Elevations

Terracon selected the exploration locations based on site access, utility, and traffic safety considerations. After drilling, the boring locations and ground surface elevations were surveyed by the project surveyor. The boring northing, easting, latitude, longitude, and elevation are shown on each boring log.

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Subsurface Exploration Procedures

Disturbed samples were collected from the borings using a 2-inch-outside diameter split-spoon sampler following Standard Penetration Test (SPT) methods in general accordance with ASTM D1586. Encountered soils were visually classified at the time of drilling per ASTM D2488. At select depths, Terracon used a 3-inch-outside-diameter split-spoon sampler (ring sampler) to obtain a larger sample quantity of the native granular soils. In our engineering evaluation, the blow counts required to drive the larger 3-inch-outside-diameter split-spoon sampler were corrected using the Lacroix-Horn equation (ASTM STP-523, 1973) to account for the larger sampler size and represent standard SPT N-values. The boring logs show the uncorrected blow counts that were recorded in the field. In addition to SPT samples, relatively undisturbed samples were occasionally obtained by pushing a thin-walled, seamless steel tube with a sharp cutting edge hydraulically into the soil. Quantities, locations, and depths are presented on the boring logs in Appendix A.

The SPT N-value provides a reasonable estimate of the relative in-place density of non-cemented sandy type materials. However, the N-value only provides an indication of the relative stiffness of cohesive materials since the penetration resistance of these soils may be affected by the moisture content. Considerable care must be exercised in interpreting the N-value in gravelly soils, particularly where the size of the gravel particles exceeds the inside diameter of the sampling spoon.

An automatic SPT hammer was used to advance the split-spoon sampler in the borings performed for this project. Greater efficiency is typically achieved with the automatic hammer compared to the conventional safety hammer operated with a cathead and rope. Published correlations between the SPT values and soil properties are based on the cathead and rope method. The higher efficiency of the automatic hammer affects the standard penetration resistance blow count (N-value) by increasing the penetration per hammer blow over what would be obtained using the cathead and rope method. The effect of the automatic hammer's efficiency has been considered in the interpretation and analysis of the subsurface information for this report.

Laboratory Testing

Soil samples collected in the field were taken to the laboratory where soils were visually classified using the Unified Soil Classification System and in general accordance with ASTM D2488, or ASTM D2487 where laboratory data was available. The Unified Soil Classification System is described in Appendix C. Representative samples were selected for testing to determine the engineering and physical properties of the soil. The following table lists the tests performed and provides a brief description of the purpose of each.

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Table 2. Laboratory Testing

Tests Conducted To Determine

Moisture Content (ASTM D2216) Moisture content of the soil sample.

Sieve Analysis (ASTM D6913) Particle distribution of the soil sample Percent Passing the No. 200

Sieve (ASTM D1140) Percent of clay/silt sized particles in the sample.

Atterberg Limits (ASTM D4318) Plasticity Index, Liquid Limit, and Plastic Limit of the soil sample.

R-Value (Idaho T-8) Resistance “R”-Value and expansion pressure of a sample (used in the design of pavement sections) pH (ASTM D4972) and Minimum Resistivity (ASTM G187)

Corrosion potential of metals in contact with soil.

Note: Laboratory tests were conducted in general accordance with their respective ASTM standards.

Results of the field and laboratory tests are generally summarized on the boring logs in Appendix A. Graphical results of the Atterberg limits and gradation analyses are included in Appendix B. Corrosion analyses results are presented in Appendix B. The laboratory test data, along with the field information, were used to prepare the boring logs.

240.05 TOTAL DESIGN PAVEMENT THICKNESS

Subgrade Support Characteristics

The subgrade strength was estimated from the results of laboratory moisture content, and R-value tests on samples of the subgrade soil as presented in Appendix B.

Terracon used a subgrade R-value of 30 based on the classification of the subgrade soils and converted it to a subgrade resilient modulus using the correlation equation provided in Table 520.08.03.03.02.1 of the Materials Manual, resulting in a design subgrade resilient modulus of 15,000 psi.

Traffic

ITD provided the Projected Traffic Volumes for Eckert Road, which include the Commercial Annual Average Daily Traffic (CAADT) for 2027 and 2047. The provided traffic information is presented in Appendix C. ACHD has requested a Superpave class of SP-5 and PG binder grade of 70-28 for Eckert Road.

Data from TTC #16 was used to estimate the direction distribution of the commercial traffic. ATR #80 was selected to determine the lane distribution. The ATR data is

July 24, 2026 | Terracon Project No. 62235109B

Facilities | Environmental | Geotechnical | Materials 6 presented in Appendix C. The parameters used for the AASHTOWare Pavement ME traffic analysis are summarized in the table below.

Table 3: Design Pavement Traffic Parameters

Parameter AASHTOWare Pavement ME Analysis

Eckert Road

Opening Year 2027

Design Life 20

Two-way CADT 160

Compound Growth Rate 2.3%

Axle Load Spectra 1 Statewide Average

Number of Lanes in Design Direction 1

Directional Split 60%

Lane Split 2 100%

Operational Speed 25 mph 3

Traffic Capacity Cap Not Enforced

1. The “ITD Axle Load Spectra – Statewide Average” .xml file was imported for Axle Load Distributions.

2. Value was estimated based on the guidance provided in Section 500 of the ITD Materials Manual

3. Value was based on the currently posted speed for corners adjacent to the site. A slower operational speed provides a more conservative design.

Project specific weigh-in-motion or truck distribution data was not available. Therefore, the weigh-in-motion data from TTC #16 was used to estimate the vehicle class distribution. The vehicle class distribution used for the AASHTOWare Pavement ME traffic analyses are summarized in the table below.

Table 4: Design Vehicle Class Distribution

FHWA

Vehicle

Classification 4 5 6 7 8 9 10 11 12 13

Distribution (%) 1.3 48.4 10.8 1.9 6.7 13.4 4.3 0.5 0.1 12.6

Pavement Thickness Design Recommendations

Flexible pavement design analyses were completed using the AASHTOWare Pavement ME software in general accordance with Section 520 of the ITD Materials Manual. The

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Facilities | Environmental | Geotechnical | Materials 7 performance parameters used in the AASHTOWare Pavement ME new flexible pavement analysis are summarized in the table below.

Table 5: Design Pavement Performance Criteria

Parameter AASHTOWare Pavement ME Analysis

Eckert Road

Design Life (years) 20 Design Reliability (%) 90 Terminal IRI (in/mile) 175

Permanent deformation – total pavement (in) 0.50

AC bottom-up fatigue cracking (% lane area) 15%

AC Thermal Cracking (ft/mile) 1,500 Permanent deformation – AC only (in) 0.50

A starting point for thickness design was established using the ITD R-value Design Method. These thicknesses were refined in the ME design iterations. Using the calculated traffic and the ITD SuperPave .xml files, flexible pavement sections were developed.

Resilient moduli (psi) values for subbase and base materials were estimated using Figure

520.08.05.1 of the ITD Materials Manual. The AASHTOWare Pavement ME output reports are presented in Appendix C.

Pavement Thickness

The proposed flexible pavement section developed using AASHTOWare Pavement ME for Eckert Road is presented in the table below.

Table 6: Eckert Road Pavement Section

Material / Parameter Thickness, feet (inches)

New HMA (½-inch SP-5) 1 0.42 (5.0)

Aggregate Base (¾ inch Type B) 0.33 (4.0)

Granular Subbase 0.67 (8.0)

Total Pavement Section 1.42 (17.0)

1. The HMA should be placed in two approximately equal lifts.

We understand that a standard Temporary Pavement Section will be used as part of this project.

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Table 7: Temporary Pavement Section

Material / Parameter Thickness, feet (inches)

New HMA (½-inch SP-3) 1 0.33 (4.0)

Aggregate Base (¾ inch Type B) 0.33 (4.0)

Granular Subbase 0.67 (8.0)

Total Pavement Section 1.33 (16.0)

2. The HMA should be placed in two approximately equal lifts.

240.06 SUB-SUBGRADING

Sub-subgrading is not anticipated for this project.

240.07 GRADE POINTING

Grade pointing is not anticipated for this project.

240.08 SPECIAL PLACEMENT

Special placement is not anticipated for this project.

240.09 COMPACTION

HMA and granular pavement section materials should be compacted in accordance with ITD specifications. Compaction associated with soft spot repair and all other compaction should be Class A unless otherwise specified.

240.10 SLOPE DESIGN SUMMARY

We understand that the fill slopes of the embankments will have maximum heights of approximately 25 feet. These slopes should be constructed using appropriate erosion control measures. The slope design summary is presented below.

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Table 8: Slope Design Summary

Location Operation Approximate

Height (feet)

Shrink/Swell (Volume

Change)1 Slope2 Special

Treatments Embankment Areas (Bridge Approaches)

Fill 0 to 25 -3 to -11% Maximum

2:1 Not anticipated

1. Based on anticipated materials, information in Excavation Handbook, and our experience with similar soils.

2. Slope ratio indicated is horizontal to vertical.

240.11 SLOPE DESIGN

Permanent slopes should have inclinations of 2:1 (horizontal to vertical) or flatter.

Flatter slopes may be required for safety, aesthetic, or other purposes. Some sloughing and raveling of the soil slope faces may occur, particularly when soils are exposed to weathering or precipitation for long periods of time. Appropriate mitigation measures should be included during construction to reduce potential erosion.

The Contractor is responsible for designing and constructing stable, temporary excavations and slopes, and for protecting existing facilities/utilities that will remain in place. Excavations should be sloped or shored in accordance with local, state and federal regulations, including current OSHA excavation and trench safety standards.

240.12 EMBANKMENT FOUNDATION

The new embankments will be founded on native soils and new embankments are anticipated to be less than 25 feet in height. Settlement of the embankment is estimated to be approximately 3 inches or less. Due to the typically granular nature of the soils encountered in the borings, we estimate this settlement will occur quickly, as the embankments are constructed. Class A compaction is recommended for the embankments associated with the project. Settlement monitoring is not recommended for the Embankment.

240.13 SURFACE AND SUBSURFACE WATER

The Boise River and the Ridenbaugh Canal are the primary surface drainage features within the project limits. The Boise River generally trends northwest/southeast.

Ridenbaugh Canal is an irrigation feature that generally trends northwest/southeast. The

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Boise River crosses under Eckert Road, its approximate location is shown on Exploration Plans in Appendix A.

Groundwater was encountered in some explorations completed for this project and are summarized in the following table:

Table 9: Summary of Groundwater Observed During Drilling

Boring

ID

Ground Surface Elevation

(ft) Above Mean Sea Level Date

Groundwater While Drilling

Depth (ft) Elevation (ft) Above Mean Sea Level

B-2 2771.3 2/18/2025 22 2749.3

B-3 2750.1 2/27/2025 0 1 2750.1

B-4 2750.1 2/25/2025 0 1 2750.1

B-5 2749.8 2/20/2025 0 1 2749.8

B-6 2765.0 2/24/2026 12.9 2752.1

RW-15 2762.2 12/1/2026 11.6 2750.6

RW-16 2759.4 12/1/2026 9.3 2750.1

1. Boring was drilled in the Boise River.

Groundwater level fluctuations occur due to seasonal variations in the amount of precipitation, out flow from upriver reservoirs, flood control measures, runoff, irrigation, and other factors not evident at the time of exploration.

240.14 DRAINAGE

Surface water throughout the project should be collected and drained away from pavements, embankments, structures, and critical areas to prevent standing water, erosion, and saturation of the subgrade soils. Care should be taken to slope paved areas and shoulders sufficiently to provide rapid drainage away from pavement edges.

Discharge areas should be protected with riprap underlain by a Riprap/Erosion Control Geotextile per Section 718.06 of the Standard Specifications for Highway Construction.

As MSE walls will be constructed for the bridge approaches, surface drainage features should be incorporated into design to prevent salt-laden water from soaking into the MSE wall reinforced zones and/or sheet draining over the MSE wall faces. Such features could include paving the entire top surface up to all MSE wall faces, where applicable;

and providing raised curbs and drain inlets to collect surface runoff and direct it away from MSE walls.

Northeast of the Abutment 2, a portion of the multi-use path will drain into or behind the reinforced zone of the MSE wall. We understand that the multi-use path will not be

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Facilities | Environmental | Geotechnical | Materials 11 salted during winter weather conditions. However, Eckert Road will be treated for traction during winter weather conditions, and salting may be one of those treatments.

Eckert Road will be sloped to drain away from this drainage area. Even with these measures, salt-laden water may drain into or behind the reinforced zone of the MSE wall. The wall designer for this MSE wall should select a corrosion resistance reinforcement and account for sacrificial thickness of the reinforcement, as needed.

The abutments should be designed to resist hydrostatic pressures. Walls should either be designed to resist hydrostatic pressures or should include a drainage layer extending to appropriate outlet locations to reduce the potential for hydrostatic pressure on the walls. The drainage layer should consist of drain rock composed of Drain Rock as defined in Section 711.01 Drain Rock of the 2025 Supplemental Specifications to the 2023 ITD Standard Specifications for Highway Construction. The Drain Rock layer should be a minimum of 30 inches thick and should be separated from other soils with a Drainage Geotextile. The Drain Rock layer should extend vertically from the base of the structure to within 3 feet of the ground surface. Weep holes in the walls may also be used in conjunction with the drainage layer to reduce the potential for hydrostatic pressures. As an alternative to Drain Rock, manufactured drainage panels installed in accordance with the manufacturer’s recommendations may be used.

240.15 GEOSYNTHETICS

Geosynthetics are not anticipated for this project.

240.16 EXISTING ROADWAY MATERIAL

Areas of existing asphaltic concrete surfacing and underlying base/subbase materials that are to be abandoned/obliterated may be reutilized as Granular Barrow, provided the project specifications for use at the intended locations are met. If the existing asphaltic concrete is reused as reclaimed asphalt pavement (RAP) in new embankments, the asphalt concrete should be reduced to a maximum particle size of three inches, and thoroughly mixed and evenly dispersed into the new fills. The existing asphaltic concrete should not be left in-place beneath new fills.

240.17 ROCK SUBGRADE

Rock was not encountered within the explorations. Therefore, rock subgrade is not anticipated for this project.

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240.18 TOPSOIL

Topsoil should be stripped from beneath proposed new construction areas. For estimating purposes, the depth of stripping is assumed to be 4 inches in other areas of the project alignment. The depth of topsoil stripping is likely deeper where mature vegetation exists. If the stripped soil meets the requirements for topsoil outlined in Section 213 of the ITD Standard Specifications for Highway Construction, it may be used for landscaping. If the stripped material does not meet the requirements for topsoil, it may be processed to meet the topsoil requirements or removed from the site and wasted in accordance with appropriate regulations. If additional topsoil is required for landscaping, it should be obtained from approved Contractor furnished sources.

240.19 PIPE

Pipes are not anticipated for this project. Resistivity and pH testing that was completed for this project are presented in Appendix B.

240.20 RIPRAP

Riprap is anticipated for the Ridenbaugh Canal and Boise River Bridges and is discussed in the Geotechnical Engineering Reports for each of the structures.

240.21 STAGED CONSTRUCTION

Based on the native granular soils and the depth of the groundwater, staged construction does not appear to be necessary to allow for consolidation of soils following placement of embankments.

240.22 PAVEMENT DATA

240.22.01 Pavement Type and Pavement Smoothness

Pavement surface smoothness should be in accordance with Straightedge requirements.

240.22.02 Typical Sections

Typical pavement sections are included in Appendix C.

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240.23 BASE

Aggregate Base course and Granular Subbase should be provided from an approved Contractor furnished source. Aggregate Base should conform to the requirements in ITD Standard Specifications Section 703 for ¾-inch crushed Aggregate for Untreated Base Type B.

240.23.02 Tack Coat

Place tack at construction joints and between lifts of new HMA, where applicable. Use CSS-1 or CSS-1h Diluted Emulsified Asphalt for Tack Coat at 0.20 (estimated) gallon per square yard on vertical faces, and 0.10 (estimated) gallon per square yard between lift surfaces of HMA, where applicable.

240.23.03 Prime Coat

A prime coat is not anticipated for this project.

240.24 SURFACE TREATMENT

A surface treatment is not anticipated for this project.

240.25 PAVING

240.25.03 Class of HMA Recommendation

For estimating purposes only, use the following material properties:

½-inch PG 70-28 Class SP-5 Superpave Hot Mix Asphalt (HMA) at 5.0 percent by total weight of mix for the final lift. Add anti-stripping additive to the asphalt cement at a rate of 0.5 percent by weight of asphalt cement.

240.25.04 Performance Graded Binder Selection

Terracon considered the weather conditions and traffic to determine the appropriate asphalt binder for this project. This was accomplished using the LTPPBind software developed by the Federal Highway Administration (FHWA). This software utilizes historical temperature data from weather stations near the project to establish a recommended Performance Graded (PG) binder grade of asphalt concrete. Terracon then

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Facilities | Environmental | Geotechnical | Materials 14 compared the software output to the binders that were indicated to be locally available to determine the recommended binder selection for the project. A PG of 64-28 is applicable based on the LTPPBind results and local availability. However, we understand ACHD has requested PG 70-28 to be used for this project.

240.26 SEAL

A seal coat is not anticipated for this project.

240.27 DUST ABATEMENT

Dust abatement quantities for the widening may be estimated at 174 MG (174,000 gallons), based on an application rate of 4 inches of water per square foot of roadway. A worksheet showing dust abatement quantities is presented in Appendix C.

240.28 AGGREGATE ESTIMATING DATA

The unit weights for this estimating basis were determined from area history and past project experience. This information is provided for use by the designer in developing reasonable project quantities. The actual quantities will vary, and are dependent on the Contractor provided materials source, crushing operation, and mix designs. The Contractor is responsible for determining actual unit weights based on the material produced and providing adequate materials for the project plus any losses due to stockpile operation, out of specification (rejected) materials, or other waste.

The estimated unit weight of the ½-inch aggregate for Superpave Class SP-5 HMA is 144 lb/ft3 (compacted), including 5.5 percent PG 70-28 asphalt cement and 0.5 percent anti-strip by weight of asphalt.

The estimated unit weight of ¾-inch Type-B Aggregate for Untreated Base is 143 lb/ft3

(compacted), including 7 percent moisture.

The estimated unit weight of Granular Subbase is 135 lb/ft3 (compacted), including 4 percent moisture.

240.29 AGGREGATE SOURCES

Designated Source(s) are not identified for this project. Approved Contractor furnished sources will be used.

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240.30 CURRENT SPECIFICATIONS AND MINIMUM

TESTING REQUIREMENTS

This Roadway Materials Report is based upon the ITD Standard Specifications for Highway Construction (2023), the Supplemental Specifications for the Idaho Standard Specifications for Highway Construction (2025) and the ITD Quality Assurance Manual (2019).

240.31 SPECIAL PROVISION ITEMS

Special provisions or modifications to the Standard Specifications for Highway Construction or the Supplemental Specifications for the Standard Specifications for Highway Construction are not anticipated for the items discussed in this report.

Notes to Contractor

ESTIMATING BASIS. The unit weights in the estimating basis were determined from area history and past project experience. This information is provided for use by the designer in developing reasonable project quantities. The actual quantities will vary and are dependent on the Contractor provided materials sources, crushing operations, and mix designs. The Contractor is responsible for determining actual unit weights based on the material produced and providing adequate materials for the project plus any losses due to stockpile operation, out of specification (rejected) materials, or other wastes.

EXCESS MATERIALS. Excess materials shall conform to the requirements of Subsection 205.03.A (A) - General. All excess or unsuitable material removed from the project becomes the property of the Contractor.

PAVEMENT SURFACE SMOOTHNESS. Surface smoothness shall be in accordance with straightedge requirements.

SAWCUTTING. Sawcutting of existing curb and gutter, concrete sidewalk surface, concrete pavement surface and asphalt shall be incidental to related removal items. No additional payment will be provided for sawcutting.

SOFT SUBGRADE SOILS. The Contractor should anticipate encountering soft, moisture sensitive subgrade soils during construction. These soils may be prone to rutting or pumping under construction machinery. It is the responsibility of the Contractor to protect these soils during construction activities. The Contractor shall determine how to best achieve this requirement. No separate measurement or payment will be made for any excavation or replacement of excavated material below subgrade elevation made necessary due to construction activities.

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TACK COAT. Substitution of CSS-1H for CSS-1 Tack Coat will be allowed as approved by the Engineer. Tack Coat to be placed between lifts of flexible pavement.

Notes to Designer

QC/QA. Construct this project using QC/QA specifications. Associated materials verification testing will be performed by the Idaho Transportation Department.

240.32 REFERENCES

American Association of State Highway and Transportation Officials, AASHTO LRFD Bridge Design Specifications, 10th Edition, 2024.

Church, H.K., Excavation Handbook, 1981.

Idaho Transportation Department, Materials Manual, October 2020.

Idaho Transportation Department, Roadway Design Manual, 2013.

Idaho Transportation Department, Standard Specifications for Highway Construction, 2023.

Idaho Transportation Department, 2024 Supplemental Specifications for the 2023 Idaho Standard Specifications for Highway Construction, 2025.

GENERAL COMMENTS

The analysis and recommendations presented in this report are based upon the data obtained from the explorations performed at the indicated locations and from other information discussed in this report. This report does not reflect variations that may occur between explorations, across the site, or due to the modifying effects of construction or weather. The nature and extent of such variations may not become evident until during or after construction. If variations appear, we should be immediately notified so that further evaluation and supplemental recommendations can be provided.

The scope of services for this project does not include either specifically or by implication any environmental or biological (e.g., mold, fungi, and bacteria) assessment of the site or identification or prevention of pollutants, hazardous materials or conditions. If the owner is concerned about the potential for such contamination or pollution, other studies should be undertaken.

This report has been prepared for the exclusive use of our client for specific application to the project discussed and has been prepared in accordance with generally accepted

July 24, 2026 | Terracon Project No. 62235109B

Facilities | Environmental | Geotechnical | Materials 17 geotechnical engineering practices. No warranties, either express or implied, are intended or made. Site safety, excavation support, and dewatering requirements are the responsibility of others. If changes in the nature, design, or location of the project as outlined in this report are planned, the conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing.

APPENDIX A

Contents:

■ Site Location

■ Exploration Plan

■ Boring Logs

■ Photography Log

Terracon Project No. 62235109B | ITD Key No. 12811

Facilities | Environmental | Geotechnical | Materials

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Site Location

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS

Terracon Project No. 62235109B | ITD Key No. 12811

Facilities | Environmental | Geotechnical | Materials

Exploration Plan

DIAGRAM IS FOR GENERAL LOCATION ONLY, AND IS NOT INTENDED FOR CONSTRUCTION PURPOSES MAP PROVIDED BY MICROSOFT BING MAPS

2777.8

2776.6

2773.1

2772.2

ASPHALT, approximately 3-1/2" thick

FILL - POORLY GRADED GRAVEL WITH SILT AND

SAND, with cobbles, brown and gray

WELL GRADED GRAVEL WITH SILT AND SAND

(GW-GM), brown and gray, very dense

POORLY GRADED GRAVEL WITH SILT AND SAND

(GP-GM), brown and gray, very dense

Boring Terminated at 5.9 Feet

Boring Log No. B-1

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2778.1 (Ft.)

G ra p h ic

L o g

10.03.0

0.3

1.5

5.0

5.9

0.7

0.9

0.9

16-36-28 N=64

31-49-50 N=99

41-50/5"

Advancement Method Hollow-stem auger

Notes

Water Level Observations Groundwater not encountered

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME-75

Driller Haz-Tech Drilling, Inc.

Logged by

JL

Boring Started 02-18-2025

Boring Completed 02-18-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite Surface Capped with Asphalt

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5648° Longitude: -116.1333°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su lt s

2771.1 2770.8

2767.8 2766.8

2754.8 2753.8

2751.3

2749.8

2722.3

2718.3

ASPHALT, approximately 2-1/2" thick

FILL - POORLY GRADED GRAVEL WITH SILT AND

SAND, brown FILL - SILTY GRAVEL WITH SAND, brown and grayFILL - POORLY GRADED GRAVEL WITH SILT AND SAND, brown and gray FILL - SILTY GRAVEL WITH SAND, with cobbles, grayish brown and gray

SANDY SILT (ML), brown POORLY GRADED GRAVEL WITH SAND (GP), with cobbles, light tan and gray, very dense

WELL GRADED GRAVEL WITH SAND (GW), brown and gray, very dense POORLY GRADED GRAVEL WITH SAND (GP), with cobbles and boulders, with clay lenses, light tan and gray, very dense

SILTY SAND (SM), with gravel lenses, light orangish brown and tan, very dense, interbedded with layers of sandy silt

SANDY FAT CLAY (CH), brown, hard

Boring Log No. B-2

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2771.3 (Ft.)

G ra p h ic

L o g

14.8

3.6

3.2

6.5

2.8

6.9

0.2 0.5

3.5 4.5

16.5 17.5

20.0

21.5

49.0

53.0

0.9

0.9

1.2

1.1

0.8

1.3

1.2

0.9

1.1

0.9

0.8

0.5

1.4

4-5-3 N=8

6-10-35 N=45

11-20-25

8-8-13 N=21

11-17-19

7-3-3 N=6

18-39-50 N=89

23-31-63

13-26-30 N=56

32-60-80/4"

28-50/5"

29-80/4"

50/5"

23-49-50 N=99

Advancement Method Hollow-stem auger

Notes

Water Level Observations

22 feet after completion of drilling

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME-75

Driller Haz-Tech Drilling, Inc.

Logged by

JL

Boring Started 02-18-2025

Boring Completed 02-19-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite Surface Capped with Asphalt

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5654° Longitude: -116.1328°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su

2713.3

2693.3

2679.8

SANDY FAT CLAY (CH), brown, hard (continued)

POORLY GRADED SAND WITH SILT (SP-SM), light brown to tan, very dense, interbedded with layers of silty sand

POORLY GRADED SAND (SP), light brown, very dense

Boring Terminated at 91.5 Feet

Boring Log No. B-2

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2771.3 (Ft.)

G ra p h ic

L o g

68.126.3 50-22-28

58.0

78.0

91.5

1.5

1.5

1.4

1.2

1.3

1.2

1.3

1.2

19-26-29 N=55

25-40-50 N=90

25-47-50 N=97

20-38-47 N=85

21-39-49 N=88

33-34-34 N=68

15-36-37 N=73

26-39-42 N=81

Advancement Method Hollow-stem auger

Notes

Water Level Observations

22 feet after completion of drilling

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME-75

Driller Haz-Tech Drilling, Inc.

Logged by

JL

Boring Started 02-18-2025

Boring Completed 02-19-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite Surface Capped with Asphalt

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5654° Longitude: -116.1328°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su

2764.8

2755.5

2751.5

2732.5

ASPHALT, approximately 2-1/4" thick

FILL - POORLY GRADED GRAVEL WITH SAND,

brown and gray trace cobbles

FILL - POORLY GRADED GRAVEL WITH SAND,

with cobbles, brown and gray

POORLY GRADED SAND (SP), tan, medium dense

POORLY GRADED GRAVEL WITH SAND (GP), with cobbles, tan and gray, medium dense to dense

POORLY GRADED SAND (SP), trace gravel, light brown, medium dense

POORLY GRADED GRAVEL WITH SAND (GP), with cobbles, tan and gray, very dense

POORLY GRADED SAND WITH SILT (SP-SM), light brown, dense to very dense interbedded with layers of silty sand

Boring Log No. B-6

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2765.0 (Ft.)

G ra p h ic

L o g

4.7

2.4 1.9

4.8

4.2

24.2 9.3

21.6

0.2

9.5

13.5

16.0

28.0

32.5

45.0

1.2

0.7

0.8

1.2

1.1

1.5

0.6

1.4

1.2

0.1

1.5

1.5

5-24-32 N=56

15-2-31

8-22-13 N=35

16-23-20

15-39-35 N=74

5-12-16

8-8-9 N=17

26-40-42

7-13-13 N=26

80/1"

50/1"

23-39-56

15-38-50 N=88

Advancement Method Hollow-stem auger

Notes

Water Level Observations

12.9 feet 10 minutes after completion of drilling

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME-75

Driller Haz-Tech Drilling, Inc.

Logged by

JL

Boring Started 02-24-2025

Boring Completed 02-25-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite Surface Capped with Asphalt

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5659° Longitude: -116.1317°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su

2697.5

2673.5

POORLY GRADED SAND WITH SILT (SP-SM), light brown, dense to very dense (continued)

SILTY SAND (SM), brown, very dense

POORLY GRADED GRAVEL WITH SILT AND SAND

(GP-GM), brown, very dense SILTY SAND (SM), with sand and gravel lenses, light brown to tan, very dense

LEAN CLAY (CL), tan and browinsh orange, hard, interbedded with layers of poorly graded sand with silt

Boring Terminated at 91.5 Feet

Boring Log No. B-6

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2765.0 (Ft.)

G ra p h ic

L o g

34.8

21.0

28.1

22.8

NP

58.0

66.0

67.5

83.0

91.5

1.4

1.5

1.4

1.5

1.5

1.5

1.5

1.5

26-35-35 N=70

22-39-42 N=81

14-22-50/5"

34-35-50 N=85

32-38-45 N=83

31-49-50 N=99

22-42-50 N=92

20-34-48 N=82

Advancement Method Hollow-stem auger

Notes

Water Level Observations

12.9 feet 10 minutes after completion of drilling

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME-75

Driller Haz-Tech Drilling, Inc.

Logged by

JL

Boring Started 02-24-2025

Boring Completed 02-25-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite Surface Capped with Asphalt

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5659° Longitude: -116.1317°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su

2761.7

2759.4

2757.9

2756.9

2755.4

ASPHALT, approximately 2-1/2" thick

FILL - POORLY GRADED GRAVEL WITH SILT AND

SAND, with cobbles, brown and gray

FILL - SILTY SAND (SM), brown and gray

SILTY SAND (SM), dark brown

SILTY GRAVEL WITH SAND (GM), dark brown and gray, loose

Boring Terminated at 6.5 Feet

Boring Log No. B-7

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2761.9 (Ft.)

G ra p h ic

L o g

15.5

37.6

7.2

10.3

0.2

2.5

4.0

5.0

6.5

1.3

0.8

0.3

11-16-19 N=35

5-7-4 N=11

7-4-4 N=8

Advancement Method Hollow-stem auger

Notes

Water Level Observations Groundwater not encountered

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME-75

Driller Haz-Tech Drilling, Inc.

Logged by

JL

Boring Started 02-19-2025

Boring Completed 02-19-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite Surface Capped with Asphalt

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5662° Longitude: -116.1311°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su

FILL - SILT WITH GRAVEL, with organics, dark brown

FILL - SANDY SILT, with organics and trace gravel, brown

FILL - POORLY GRADED GRAVEL WITH SILT AND

SAND, with cobbles, brown and gray

POORLY GRADED GRAVEL WITH SILT AND SAND

(GP-GM), with cobbles and boulders, very dense

Boring Terminated at 30.7 Feet

2789.9

2788.4

2782.4

2761.7

Boring Log No. RW-13

W at er L ev el

O bs er va tio ns

D ep th

Ft

G ra p h ic

L o g

Facilities | Environmental | Geotechnical | Materials

Elevation: 2792.4 (Ft.)

59.4

10.4

2.5

4.0

10.0

30.7

0.7

1.2

0.5

0.9

0.1

0.7

0.3

0.5

0.6

2-4-5 N=9

3-2-6 N=8

15-13-15 N=28

16-26-36 N=62

50/2"

30-50/5"

50/4"

50-50/1"

47-50/2"

6.7

1.6

Advancement Method Hollow-Stem Auger

Notes

Water Level Observations Groundwater not encountered

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME 75

Driller Haz-Tech Drilling, Inc.

Logged by

KU

Boring Started 12-01-2025

Boring Completed 12-01-2025

Abandonment Method Boring backfilled with Bentonite

S am pl e

T yp e

Pe rc en t

Fi n esLatitude: 43.5644° Longitude: -116.1336°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su lt s

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

2778.9

SILTY GRAVEL WITH SAND (GM), with cobbles and organics, brown and gray, medium dense

POORLY GRADED GRAVEL WITH SILT AND SAND

(GP-GM), with cobbles and boulders, gray and brown, very dense

Boring Terminated at 30.4 Feet

Boring Log No. RW-14

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2781.4 (Ft.)

G ra p h ic

L o g

5.7

7.2

1.0

1.3

2.5

30.4

0.5

0.4

0.6

1.1

0.1

0.9

0.3

0.3

0.3

3-9-9 N=18

29-50/4"

30-50/5"

19-36-48 N=84

50/2"

24-44-50/5"

50/5"

50/5"

50/5"

Advancement Method Hollow-Stem Auger

Notes

Water Level Observations Groundwater not encountered

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig CME 75 (track mounted)

Driller Haz-Tech Drilling, Inc.

Logged by

CM

Boring Started 11-26-2025

Boring Completed 11-26-2025

Abandonment Method Boring backfilled with Auger Cuttings and Bentonite

S am pl e

T yp e

Pe rc en t

Fi n es

R e si st iv it y

(o h m

-c m

W at er C o n te n t

) Atterberg

Limits

LL-PL-PI

See Exploration PlanLocation:

Latitude: 43.5648° Longitude: -116.1334°

Depth (Ft.)

R e co ve ry

Ft p H

Fi el d T es t

R e su

2761.9

2759.7

2757.2

2754.7

2752.2

2747.2

2737.2

2732.2

2730.7

ASPHALT, Approximately 3 1/2" thick

FILL - POORLY GRADED GRAVEL WITH SILT AND

SAND, with cobbles, brown

FILL - SILTY SAND WITH GRAVEL, with cobbles, dark brown

CLAYEY SAND WITH GRAVEL (SC), dark brown

SILTY SAND (SM), with trace gravel, brown, loose

SILTY SAND WITH GRAVEL (SM), with cobbles, brown, dense

POORLY GRADED GRAVEL WITH SILT AND SAND

(GP-GM), with cobbles, brown and gray, very dense

SILT (ML), brown, stiff to very stiff

POORLY GRADED GRAVEL WITH SILT AND SAND

(GP-GM), with cobbles, brown and gray, very dense Boring Terminated at 31.5 Feet

Boring Log No. RW-15

W at er L ev el

O bs er va tio ns

D ep th

Ft

Facilities | Environmental | Geotechnical | Materials

Elevation: 2762.2 (Ft.)

G ra p h ic

L o g

23.4

64.1

17.3

24.7 NP

0.3

2.5

5.0

7.5

10.0

15.0

25.0

30.0

31.5

1.33

0.41

0.33

1.25

0.91

0.83

1.5

1.16

12-21-25 N=46

6-4-3 N=7

3-2-2 N=4

2-2-2 N=4

2-3-26 N=29

50-36-49 N=85

20-29-33 N=62

2-4-11 N=15

22-26-36 N=62

Advancement Method Hollow-Stem Auger

Notes

Water Level Observations While drilling

See Exploration and Testing Procedures for a description of field and laboratory procedures used and additional data (If any).

See Supporting Information for explanation of symbols and abbreviations.

Elevation Reference: Elevations interpreted from survey data.

Eckert Bridge - Concept Design

Hammer Type Automatic

Eckert Road Bridge over the Boise River | Boise, Idaho

Terracon Project No. 62235109 Boise, ID

11849 W Executive Dr Ste G

Drill Rig

CME 75

Driller Haz-Tech Drilling, Inc.

Logged by

KU

Boring Started 12-01-2025

Boring Completed 12-01-2025

Abandonment Method Boring backfilled with Auger…