CO FLAP LPL 10(1) Lake Nighthorse Access Final PVMNT Report.pdf

FHWA CENTRAL FEDERAL LANDS HIGHWAY DIVISION (CFLHD)

FINAL PAVEMENT REPORT

LAKE NIGHTHORSE ACCESS ROAD – CO

FLAP LPL 10(1)

OCTOBER 25, 2024

FINAL PAVEMENT

REPORT

LAKE NIGHTHORSE

ACCESS ROAD – CO FLAP

LPL 10(1)

FHWA CENTRAL FEDERAL LANDS HIGHWAY

DIVISION (CFLHD)

PROJECT NO.: 73012219

DATE: OCTOBER 25, 2024

WSP USA ENVIRONMENT & INFRASTRUCTURE INC.

4221 BALLOON PARK ROAD, NE

ALBUQUERQUE, NM 87109

T: +1 505 821 1801

WSP.COM

October 25, 2024

FHWA Central Federal Lands Highway Division (CFLHD) 12300 W. Dakota Avenue Lakewood, CO 80228

Attention: Ms. Tammy Eggers

Subject: Final Pavement Report Lake Nighthorse Access Road

CO FLAP LPL 10(1)

Durango, CO

Dear Ms. Eggers:

WSP USA Environment & Infrastructure Inc. (WSP) has completed a final pavement report in support of the roadway and infrastructure improvements for the Lake Nighthorse access road and cobble and gravel surfaced parking lot within the Lake Nighthorse Recreation Area in Durango, Colorado.

This final pavement report is to satisfy Task P6 Activity V2 as outlined in the CO FLAP LPL 10(1) Federal Highway Administration-Central Federal Lands Highway Division (FHWA-CFLHD) Scope of Work, Contract Number 6982AF19D00008, dated April 12, 2023. This report presents a project description, a discussion of roadway subgrade conditions, and recommended flexible pavement structure thicknesses. Task P6 Activity V1 deliverables including the field investigation plan and preliminary pavement recommendations technical memo have been submitted under separate covers.

We at WSP are committed to providing quality pavement engineering services combined with client satisfaction to achieve a continuing relationship with our clients. We appreciate the opportunity to provide these services for you.

Respectfully submitted, Jeffrey S. Mann, PE (NM) Principal Materials Engineer

Lucas A. Giron, PE (NM) Senior Materials Engineer c: Addressee (PDF)

Final Pavement Design Summary Project No. 73012219 FHWA Central Federal Lands Highway Division

WSP

October 2024

TABLE OF

CONTENTS

1 INTRODUCTION

2 PROJECT SUMMARY

3 PAVEMENT SUBGRADE

CHARACTERIZATION

3.1 Site Conditions

3.2 Geotechnical Profile

4 PAVEMENT DESIGN

4.1 Design Parameters

4.1.1 Pavement Subgrade Support

4.1.2 Design Traffic and ESALs

4.1.3 Pavement Treatment and Flexible Pavement Design

4.1.3.1 Access Road

4.1.3.2 Cobble and Gravel Surfaced Parking Lot

5 MATERIAL SOURCES

6 SUBEXCAVATION

REFERENCES

Final Pavement Report

FHWA Central Federal Lands Highway Division

WSP

October 2024

Page ii

TABLES

NO TABLE OF FIGURES ENTRIES FOUND.

NO TABLE OF FIGURES ENTRIES

FOUND.PAVEMENT THICKNESS

RESULTS

APPENDICES

A SITE LOCATION PLAN/BORING LOCATION PLAN

B BORING LOGS

C LABORATORY TEST RESULTS

D PAVEMENT DESIGN CALCULATIONS

FHWA Central Federal Lands Highway Division

WSP

October 2024

1 INTRODUCTION

Presented herein are the results of the pavement design analysis completed in support of the roadway and infrastructure improvements for the Lake Nighthorse access road and cobble and gravel surfaced parking lot within the Lake Nighthorse Recreation Area in Durango, Colorado.

This final pavement report is to satisfy Task P6 Activity V2 as outlined in the CO FLAP LPL 10(1)

Federal Highway Administration-Central Federal Lands Highway Division (FHWA-CFLHD) Scope of Work, Contract Number 6982AF19D00008, dated April 12, 2023. This report presents a project description, a discussion of roadway subgrade conditions, and recommended flexible pavement structure thicknesses.

Task P6 Activity V1 deliverables, including the field investigation plan and preliminary pavement recommendations technical memo, have been submitted under separate covers.

FHWA Central Federal Lands Highway Division

WSP

October 2024

2 PROJECT SUMMARY

The purpose of this project is to improve the Lake Nighthorse access road (Segment 1) and cobble and gravel surfaced parking lot (Segment 2) due to the significant deterioration of the roadway surface and subsequent safety concerns for visitors of the recreation area. Segment 1 is

0.8 miles in length and intersects with the entrance of Segment 2. Segment 1 is approximately

16 to 18 feet wide and is an undivided access road. Segment 2 is approximately 300 feet by 300 feet. The improvements are intended to provide a remediation of the pavement surface, improve drainage, and add safety enhancements throughout the access road and parking lot. This final pavement report solely addresses pavement design considerations. A Site Location Plan and

Boring Location Plan are included in Appendix A.

FHWA Central Federal Lands Highway Division

WSP

October 2024

3 PAVEMENT SUBGRADE

CHARACTERIZATION

3.1 SITE CONDITIONS

The access road within the Lake Nighthorse Recreation Area currently consists of approximately

1/2 inch of chip seal bearing on what is commonly described as untreated base course (UTBC).

While a formal manual distress survey to determine severity and extent of pavement distress was not included in our scope of services, based on visual observations, the access road appears to be in poor condition with areas experiencing longitudinal and transverse cracking, as well as bleeding, raveling, potholes, and subgrade failure in numerous areas. The photographs below serve to document the existing access road pavement conditions.

Photograph 1: Pavement fatigue resulting from subgrade failure.

FHWA Central Federal Lands Highway Division

WSP

Photograph 2: Pavement distress identified as a pothole.

3.2 GEOTECHNICAL PROFILE

Six (6) soil test borings were performed to approximate depths of 5 feet below existing grades.

Borings P-01 through P-04 were performed within the existing access roadway prism of

Segment 1. Borings P-05 and P-06 were performed in the cobble and gravel surfaced parking lot of Segment 2.

Borings P-01 through P-04 generally encountered an approximately ½” thick asphalt seal coat

(chip seal) underlain by 4 to 6 inches of UTBC bearing on soil subgrade materials. Borings P-05 and P-06 encountered approximately 6 to 8 inches of cobbles and gravel at the surface. Soil subgrade encountered in the soil test borings generally consisted of moderately to highly plastic

A-6 and A-7-6 materials. Groundwater was not observed in the borings at the time of the field exploration. Soil moisture contents for the sampled materials ranged from 6.9 to 15.9 percent.

Boring Logs are included in Appendix B. Laboratory test results are included in Appendix C.

FHWA Central Federal Lands Highway Division

WSP

October 2024

4 PAVEMENT DESIGN

Pavement thickness design for the project was evaluated using the 2018 Federal Lands Highway

Project Development and Design Manual (PDDM) Chapter 11 - Pavements and the 1993 American

Association of State Highway Transportation Officials Guide for Design of Pavement Structures

(AASHTO 1993).

4.1 DESIGN PARAMETERS

4.1.1 PAVEMENT SUBGRADE SUPPORT

Determination of pavement subgrade support values was completed in accordance with the

PDDM – Chapter 11, Subsection 11.2.1.3 and AASHTO 1993 using laboratory determined R-values to determine the design resilient modulus (Mr). A summary of the laboratory determined R-values is presented in Table 1 below.

Table 1: Summary of R-Values (AASHTO T 190)

Boring

ID

Sample Depth Below

Existing Grade (feet)

AASHTO Group Classification

Plasticity Index

Percent Passing #200 Sieve

Laboratory Determined

R-value

P-02 2 A-7-6 30 79 4

P-03 2 A-7-6 25 59 12

P-05 2 A-6 21 81 5

From the laboratory results, an average R-value of 7 was determined. Direction provided in the

PDDM – Chapter 11, Subsection 11.2.1.3 indicates correlations with R-value results may be utilized to determine the design Mr. As such, the following equation based on AASHTO 1993 was utilized to determine the design Mr based on the average R-value of 7.

Mr=1,000+(555*(R-value))

Based on the equation above, the design Mr is estimated at 4,885 pounds per square inch (psi).

FHWA Central Federal Lands Highway Division

WSP

October 2024

4.1.2 DESIGN TRAFFIC AND ESALS

To determine the design equivalent single axle load (ESAL) conditions for the project, we utilized a 2025 design year average daily traffic (ADT) of 102 vehicles per day (VPD) and the recommended truck factors and traffic growth projections included in the PDDM – Chapter 11.

At this time, FHWA vehicle classification traffic volumes have not been provided and we understand a traffic study is not included in our Scope of Services. Table 2 below presents assumed FHWA vehicle classification traffic volumes based on general observations performed during the field exploration and scoping site visit. Truck factors included in Table 2 are based on

Exhibit 11.2-A from the PDDM – Chapter 11 and were determined based on the average values presented.

Table 2: Percent Traffic Volumes and ESAL Factors for FHWA Vehicle Classification

FHWA Vehicle Classification

Percent of Traffic Volume

ESAL Factor

1 and 2 90 0.0006

3 8 0.0035

4 - -

5 2 0.4

6 through 13 - -

Using Exhibit 11.2-A from PDDM Chapter 11 along with the ADT presented above and a traffic growth projection of 1.12 percent, we estimate the 20-year design ESALs for pavement structural thickness determination to be about 7,315. Per CFLHD direction, a minimum design 20-year

ESALs of 50,000 shall be used if the computed ESALs are below a 50,000 threshold. Therefore, 20-year ESALs of 50,000 are used to determine the asphalt concrete pavement (ACP) structural section for the project.

4.1.3 PAVEMENT TREATMENT AND FLEXIBLE PAVEMENT DESIGN

Per AASHTO M145, the site soils are identified as poor subgrade due to moderate to high plasticity and moderate risk of expansion.

4.1.3.1 ACCESS ROAD

Based on our experience with full depth reclamation applications along with guidance provided in the 2015 Basic Asphalt Recycling Manual (BARM), Full Depth Reclamation with Cement (FDR-

Cement, FP14 Section 305) appears to be a feasible pavement treatment for the access road. The observed surface distress and the presence and thickness of existing base course provides a

FHWA Central Federal Lands Highway Division

WSP

October 2024 suitable candidate for full depth reclamation. We understand CFLHD has positive experience with the FDR-cement rehabilitation treatment as this process has been utilized on projects with similar pavement surfacing thicknesses and distress conditions.

To determine the ACP overlay thickness of the FDR-cement, structural number (SN) calculations were performed using the design Mr value of 4,885 psi, design ESALs of 50,000, and design lane

ESALs per AASHTO and PDDM-Chapter 11 design methodologies. Table 3 presents the calculation inputs, resulting SN value, and layer coefficients utilized.

Table 3: Structural Number Determination – Access Road

Parameter Value

Design Resilient Modulus (Mr) 4,885 psi

20-Year Design Lane ESALs over Analysis Period (W18) 50,000

Reliability 75%

Standard Normal Random Variable (ZR) -0.674

Standard Deviation 0.49

Present Serviceability Index (Po) 4.2

Terminal Serviceability Index (Pt) 2.0

Calculated Minimum Structural Number (SN) 2.23

Structural Coefficients1

ACP 0.44

FDR-Cement 0.19

Notes:

1 Per PDDM Chapter 11, Exhibit 11.2-C Layer Types and Coefficients.

A minimum required SN of 2.23 was calculated for the overall pavement section thickness for the access road.

4.1.3.2 COBBLE AND GRAVEL SURFACED PARKING LOT

Borings P-05 and P-06 performed within the limits of the cobble and gravel surfaced parking lot encountered approximately 6 to 8 inches of cobbles and gravel at the surface underlain by

A-6 and A-7-6 soil materials. Utilizing the existing cobble and gravel materials as a compacted, reconditioned subbase (FP14 Section 303 Road Reconditioning) for the new pavement surfacing is a cost-effective pavement engineering solution. Reconditioning the existing cobble and gravel materials allows construction of the new ACP without impacting the moisture-sensitive existing

A-6 and A-7-6 materials. In addition, reconditioned cobbles and gravel provide a more competent material for the new pavement surfacing to bear on and therefore should provide a longer lasting pavement structure. We have provided a pavement structural design for the cobble and gravel surfaced parking lot incorporating the existing cobbles and gravel into the

FHWA Central Federal Lands Highway Division

WSP

October 2024 new pavement surfacing as a subbase per PDDM Chapter 11, Exhibit 11.2-C Layer Types and

Coefficients. Table 4 presents the calculation inputs, resulting SN value, and layer coefficients utilized for the parking lot.

Table 4: Structural Number Determination – Parking Lot

Parameter Value

Design Resilient Modulus (Mr) 4,885 psi

20-Year Design Lane ESALs over Analysis Period (W18) 50,000

Reliability 75%

Standard Normal Random Variable (ZR) -0.674

Standard Deviation 0.49

Present Serviceability Index (Po) 4.2

Terminal Serviceability Index (Pt) 2.0

Calculated Minimum Structural Number (SN) 2.23

Structural Coefficients1

ACP 0.44

Crushed Aggregate Base

0.12

Subbase or Minor Aggregate Base

0.10

1 Per PDDM Chapter 11, Exhibit 11.2-C Layer Types and Coefficients.

A minimum SN of 2.23 was calculated for the overall pavement section thickness for the parking lot.

Table 5 presents the resulting pavement section thicknesses for each project segment based on the minimum SN required. The results of the pavement section calculations are included in

Appendix D.

Table 5: Pavement Thickness Results

Project Segments

Thickness Recommendations (inches)

Resulting

SN ACP

FDR-

Cement

Crushed

Aggregate

Base

Subbase or Minor

Aggregate

Base

TOTAL

Access Road 3.0 5.0 - - 8.0 2.27

Parking Lot 3.0 - 4.0 6.0 13.0 2.40

FHWA Central Federal Lands Highway Division

WSP

October 2024

5 MATERIAL SOURCES

Suppliers for ACP and aggregate base are local to the Durango, Colorado area.

FHWA Central Federal Lands Highway Division

WSP

October 2024

6 SUBEXCAVATION

Per AASHTO M145, the site soils are identified as poor subgrade due to moderate to high plasticity and moderate risk of expansion. In addition, soils defined as A-6 and A-7-6 are typically moisture sensitive and may consolidate under applied construction loading.

Due to presence of the A-6 and A-7-6 materials throughout the planned construction area, a subexcavation quantity (FP14 Section 204 Excavation and Embankment - Subexcavation) is recommended to be included in the construction plans.

Based on CFL Standard C204-51, we recommend a woven Class 1 Type B geotextile per FP14

Section 714 Geosynthetic Material.

FHWA Central Federal Lands Highway Division

WSP

October 2024

REFERENCES

• Project Development and Design Manual, Chapter 11 – Pavements, Federal Lands Highway, USDOT, 2018 (PDDM).

• AASHTO Guide for Design of Pavement Structures, American Association of State Highway and Transportation Officials (AASHTO), 1993.

• Basic Asphalt Recycling Manual (BARM), Asphalt Recycling and Reclamation

Manual/FHWA, 2015.

• Standard Specifications for Construction of Roads and Bridges on Federal Highway Project, FP-14, Federal Lands Highway, USDOT, 2014.

FHWA Central Federal Lands Highway Division

WSP

October 2024

A SITE LOCATION

PLAN/BORING

LOCATION PLAN

Client:

FHWA-CFLHD

Draw By: JSM Project:

Lake Nighthorse Access Road – Preliminary Design

Date: April 24, 2024

Checked by: LG

Environment and Infrastructure, Inc.

Datum: N/A

Appendix AProjection: N/A Site Location PlanScale: NTS https://www.wsp.com/

Client:

FHWA-CFLHD

Draw By: JSM Project:

Lake Nighthorse Access Road – Preliminary Design

Date: April 24, 2024

Checked by: LG Project No. 73012219

Environment and Infrastructure, Inc.

Datum: N/A

Appendix AProjection: N/A Boring Location PlanScale: NTS https://www.wsp.com/

FHWA Central Federal Lands Highway Division

WSP

B BORING LOGS

ASPHALT SEAL COAT

UNTREATED BASE COURSE (GR)

(A-7-6) Tan brown, stiff to hard, medium to high plasticity clay

Boring terminated at 5' Sampling terminated at 6.5'

AUGER

SS

SS

A-7-6

50/4"

START TIME:

D ep th in

F ee t

M oi st ur e C on te nt

START DATE:

WSP PROJECT #:

Bl ow

C ou nt

REMARKS

COMPLETION TIME:COMPLETION DATE:

PROJECT FEATURE:

D ril l R at e

M in

/ft

HAMMER CALIBRATION-ENERGY TRANSFER RATIO:

D ry

D en si ty lb s.

p er

C ub ic ft

VISUAL CLASSIFICATION

PROJECT:

REFERENCE:

COORDINATE SYS:

SURFACE ELEV. (FT):

VERTICAL DATUM:

COORDINATES:

STATION/OFFSET:

LOGGED BY:

DRILLER:

RIG I.D.:

RIG TYPE:

BORING TYPE:

HAMMER TYPE:

Sa m pl e

G ra ph ic al Lo g

PROJECT LOCATION:

Sa m pl e

Ty pe

AA

SH

TO

s oi l

C la ss ifi ca tio n

DRILLER FIRM:

El ev at io n in

F ee t

BORING DIA.:

ORIENTATION:

A - Drill cuttings / Hand Sample SS - 2" O.D. 1.38" I.D. tube sample U - 3" O.D. 2.42" I.D. tube sample T - Thin Walled Shelby tube sample NR - No Recovery EOB - End of Boring EOS - End of Sample

DATEHOUR

BORING LOG I.D.: P-O1

METHOD

None

Durango, COLake Nighthorse Access Road

Page of

DEPTH(ft)

GROUNDWATER

WSP Global Inc.

4221 Balloon Park Rd. N.E.

Albuquerque NM 87109

73012219 Jeffrey Mann

GEOMAT

CME-55

Hollow-Stem Auger

GEOMAT

Farmington

8"

Automatic

5/22/2023 1:00 P.M 5/22/2023 12:40 P.M

37°14'25.38"N,107°54'15.37' W

13.3

7.3

(A-7-6) Tan brown, stiff to hard, medium to high plasticity clay

Boring terminated at 5' Sampling terminated at 6.5'

AUGER

SS

SS

A-2-6

A-7-6

START TIME:

D ep th in

F ee t

M oi st ur e C on te nt

START DATE:

WSP PROJECT #:

Bl ow

C ou nt

REMARKS

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D ril l R at e

M in

/ft

HAMMER CALIBRATION-ENERGY TRANSFER RATIO:

D ry

D en si ty lb s.

p er

C ub ic ft

VISUAL CLASSIFICATION

PROJECT:

REFERENCE:

COORDINATE SYS:

SURFACE ELEV. (FT):

VERTICAL DATUM:

COORDINATES:

STATION/OFFSET:

LOGGED BY:

DRILLER:

RIG I.D.:

RIG TYPE:

BORING TYPE:

HAMMER TYPE:

Sa m pl e

G ra ph ic al Lo g

PROJECT LOCATION:

Sa m pl e

Ty pe

AA

SH

TO

S oi l

C la ss ifi ca tio n

DRILLER FIRM:

El ev at io n in

F ee t

BORING DIA.:

ORIENTATION:

37°14'15'08"N,107°54' 22.83' W

A - Drill cuttings / Hand Sample SS- 2" O.D. 1.38" I.D. tube sample U - 3" O.D. 2.42" I.D. tube sample T - Thin Walled Shelby tube sample NR - No Recovery EOB - End of Boring EOS - End of Sample

DATEHOUR

BORING LOG I.D.: P-O2

METHOD

None

Durango, CO

73012219

Page of

DEPTH(ft)

GROUNDWATER

WSP Global Inc.

4221 Balloon Park Rd. N.E. Albuquerque NM

87109

Lake Nighthorse Access Road

Jeffrey Mann

GEOMAT

CME-55

Hollow-Stem Auger

GEOMAT

Automatic

Farmington

8"

12:30 P.M 12:00 P.M

5/22/2023 5/22/2023

13 15.6

12.5

(A-7-6) Tan brown, stiff to hard, medium to high plasticity clay

Boring terminated at 5' Sampling terminated at 6.5'

AUGER

SS

SS

A-2-6 A-7-6

START TIME:

D ep th in

F ee t

M oi st ur e C on te nt

START DATE:

WSP PROJECT #:

Bl ow

C ou nt

REMARKS

COMPLETION TIME:COMPLETION DATE:

PROJECT FEATURE:

D ril l R at e

M in

/ft

HAMMER CALIBRATION-ENERGY TRANSFER RATIO:

D ry

D en si ty lb s.

p er

C ub ic ft

VISUAL CLASSIFICATION

PROJECT:

REFERENCE:

COORDINATE SYS:

SURFACE ELEV. (FT):

VERTICAL DATUM:

COORDINATES:

STATION/OFFSET:

LOGGED BY:

DRILLER:

RIG I.D.:

RIG TYPE:

BORING TYPE:

HAMMER TYPE:

Sa m pl e

G ra ph ic al Lo g

PROJECT LOCATION:

Sa m pl e

Ty pe

AA

SH

TO

S oi l

C la ss ifi ca tio n

DRILLER FIRM:

El ev at io n in

F ee t

BORING DIA.:

ORIENTATION:

A - Drill cuttings / Hand Sample SS - 2" O.D. 1.38" I.D. tube sample U - 3" O.D. 2.42" I.D. tube sample T - Thin Walled Shelby tube sample NR - No Recovery EOB - End of Boring EOS - End of Sample

DATEHOUR

BORING LOG I.D.: P-O3

METHOD

None

Durango, CO

73012219

Page of

DEPTH(ft)

GROUNDWATER

WSP Global Inc.

4221 Balloon Park Rd.

N.E. Albuquerque NM

87109

Jeffrey Mann Lake Nighthorse Access Road

GEOMAT

CME-55

Hollow-Stem Auger

37°14' 04.73" N,107°54' 25.11"W

GEOMAT

Farmington

Automatic 5/22/2023 11:50 P.M

5/22/2023 11:20 A.M

8"

12.2

15.9

UNTREATED BASE COURSE

(A-6) Tan brown, stiff to hard, medium to high plasticity clay

Boring terminated at 5' Sampling terminated at 6.5'

AUGER

SS

SS

A-2-6

A-6

START TIME:

D ep th in

F ee t

M oi st ur e C on te nt

START DATE:

WSP PROJECT #:

Bl ow

C ou nt

REMARKS

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D ril l R at e

M in

/ft

HAMMER CALIBRATION-ENERGY TRANSFER RATIO:

D ry

D en si ty lb s.

p er

C ub ic ft

VISUAL CLASSIFICATION

PROJECT:

REFERENCE:

COORDINATE SYS:

SURFACE ELEV. (FT):

VERTICAL DATUM:

COORDINATES:

STATION/OFFSET:

LOGGED BY:

DRILLER:

RIG I.D.:

RIG TYPE:

BORING TYPE:

HAMMER TYPE:

Sa m pl e

G ra ph ic al Lo g

PROJECT LOCATION:

Sa m pl e

Ty pe

U ni fie d

So il

C la ss ifi ca tio n

DRILLER FIRM:

El ev at io n in

F ee t

BORING DIA.:

ORIENTATION:

37°13' 50.18" N,107°59' 19.53"W

A - Drill cuttings / Hand Sample SS - 2" O.D. 1.38" I.D. tube sample U - 3" O.D. 2.42" I.D. tube sample T - Thin Walled Shelby tube sample NR - No Recovery EOB - End of Boring EOS - End of Sample

DATEHOUR

BORING LOG I.D.: P-O4

METHOD

None

Durango, CO

73012219

Page of

DEPTH(ft)

GROUNDWATER

WSP Global Inc.

4221 Balloon Park Rd.

N.E. Albuquerque NM

87109

Jeffrey Mann Lake Nighthorse Access Road

GEOMAT

CME-55

Hollow-Stem Auger

Automatic

8"

9:00 A.M 5/22/2023 9:30 A.M

GEOMAT

Farmington

5/22/2023

10.9

9.0

COBBLES AND GRAVEL (GR)

(A-6) Tan brown, stiff to hard, medium plasticity clay

Boring terminated at 5' Sampling terminated at 6.5'

AUGER

SS

SS

A-6

START TIME:

D ep th in

F ee t

M oi st ur e C on te nt

START DATE:

WSP PROJECT #:

Bl ow

C ou nt

REMARKS

COMPLETION TIME:COMPLETION DATE:

PROJECT FEATURE:

D ril l R at e

M in

/ft

HAMMER CALIBRATION-ENERGY TRANSFER RATIO:

D ry

D en si ty lb s.

p er

C ub ic ft

VISUAL CLASSIFICATION

PROJECT:

REFERENCE:

COORDINATE SYS:

SURFACE ELEV. (FT):

VERTICAL DATUM:

COORDINATES:

STATION/OFFSET:

LOGGED BY:

DRILLER:

RIG I.D.:

RIG TYPE:

BORING TYPE:

HAMMER TYPE:

Sa m pl e

G ra ph ic al Lo g

PROJECT LOCATION:

Sa m pl e

Ty pe

AA

SH

TO

S oi l

C la ss ifi ca tio n

DRILLER FIRM:

El ev at io n in

F ee t

BORING DIA.:

ORIENTATION:

37°13' 58.03" N,107°59' 16.91"W

A - Drill cuttings / Hand Sample SS - 2" O.D. 1.38" I.D. tube sample U - 3" O.D. 2.42" I.D. tube sample T - Thin Walled Shelby tube sample NR - No Recovery EOB - End of Boring EOS - End of Sample

DATEHOUR

BORING LOG I.D.: P-O5

METHOD

None

Durango, CO

73012219

Page of

DEPTH(ft)

GROUNDWATER

WSP Global Inc.

4221 Balloon Park Rd.

N.E. Albuquerque NM

87109

Jeffrey Mann Lake Nighthorse Access Road

GEOMAT

Hollow-Stem Auger

CME-55

GEOMAT

Farmington

Automatic

5/22/2023 10:00 A.M 5/22/2023 10:30 A.M

8"

A-2-6

13.9

14.1

COBBLES AND GRAVEL (GR)

(A-7-6) Tan brown, stiff to hard, medium to high plasticity clay

Boring terminated at 5' Sampling terminated at 6.5'

AUGER

SS

SS

A-2-6

A-7-6

START TIME:

D ep th in

F ee t

M oi st ur e C on te nt Pe rc en t o f

D ry

W ei gh t

START DATE:

WSP PROJECT #:

Bl ow

C ou nt

REMARKS

COMPLETION TIME:COMPLETION DATE:

PROJECT FEATURE:

D ril l R at e

M in

/ft

HAMMER CALIBRATION-ENERGY TRANSFER RATIO:

D ry

D en si ty lb s.

p er

C ub ic ft

VISUAL CLASSIFICATION

PROJECT:

REFERENCE:

COORDINATE SYS:

SURFACE ELEV. (FT):

VERTICAL DATUM:

COORDINATES:

STATION/OFFSET:

LOGGED BY:

DRILLER:

RIG I.D.:

RIG TYPE:

BORING TYPE:

HAMMER TYPE:

Sa m pl e

G ra ph ic al Lo g

PROJECT LOCATION:

Sa m pl e

Ty pe

AA

SH

TO

S oi l

C la ss ifi ca tio n

DRILLER FIRM:

El ev at io n in

F ee t

BORING DIA.:

ORIENTATION:

A - Drill cuttings / Hand Sample SS - 2" O.D. 1.38" I.D. tube sample U - 3" O.D. 2.42" I.D. tube sample T - Thin Walled Shelby tube sample NR - No Recovery EOB - End of Boring EOS - End of Sample

DATEHOUR

BORING LOG I.D.: P-O6

METHOD

None

Durango, CO

73012219

Page of

DEPTH(ft)

GROUNDWATER

WSP Global Inc. 4221 Balloon Park Rd. N.E. Albuquerque NM

87109

Lake Nighthorse Access Road Jeffrey Mann

GEOMAT

Hollow-Stem Auger

CME-55 37°13' 59.62" N,107°54' 18.50"W

5/22/2023 11:00 A.M

8"

5/22/2023 10:40 A.M

Automatic

GEOMAT

15.9

6.9

11.6

FHWA Central Federal Lands Highway Division

WSP

October 2024

C LABORATORY

TEST RESULTS

Client: Central Federal Lands Highway Divis 12300 West Dakota Avenue Lakewood, CO 80228

Attention: Tammy Eggers

Report Date: June 01, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 1 Sampled By: Jeffrey Mann

Date Sampled: 5/22/2023

Project Manager: Jeffrey Mann

Sieve Analysis (AASHTO T11-18/T27-18) Plasticity Index (AASHTO T89-17/T90-16)

(AASHTO M145-91)Soil ClassificationSOILS / AGGREGATES

Sample Location L.L.

Soil

Class. P.I.

Lab Number

D10 D30 D60 CC CUD20 D50 D70 Cmu

P01 @ 2.0' 43 2423-0358-01 0 0 0.621 0 00 0.101 1.866 0A-7-6 P02 @ 2.0' 48 3023-0358-02 0 0 0 0 00 0 0 0A-7-6 P03 @ 2.0' 43 2523-0358-03 0 0 0.09 0 00 0 0.566 0A-7-6 P04 @ 2.0' 36 1823-0358-04 0 0 1.376 0 00 0.521 2.787 0A-6 P05 @ 2.0' 38 2123-0358-05 0 0 0 0 00 0 0 0A-6 P06 @ 2.0' 43 2323-0358-06 0 0 0 0 00 0 0 0A-7-6 P05 @ 6" 40 2123-0358-13 0 0 18.25 0 00 11 25.89 0A-2-6 www.wsp.com

File: Supplier: Other:Email:Distribution: Client:

WSP USA

4221 Balloon Park Rd NE Albuquerque, NM 87109 Tel 5058211801

X

Lakewood, CO 80228

Attention: Tammy Eggers

Report Date: June 01, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 1 Sampled By: Jeffrey Mann

Date Sampled: 5/22/2023

Project Manager: Jeffrey Mann

Sieve Analysis Plasticity Index

Soil ClassificationSOILS / AGGREGATES

Sample Location L.L.

Soil

Class. P.I. #200 #100 #50 #40 #30 #16 #10 #8 #4 3/8" 1/2" 3/4' 1" 1 1/2" 2"1 1/4"1/4" 2 1/2" 3" 6" 12" Lab Number

(AASHTO T11-18/T27-18)

(AASHTO T89-17/T90-16)

(AASHTO M145-91)

Sieve Sizes Sieve Result are as Percent Passing.

P01 @ 2.0' 43 24 48 52 56 58 60 65 71 73 82 92 96 100 23-0358-01A-7-6

P02 @ 2.0' 48 30 79 83 85 86 87 89 92 92 95 98 99 100 23-0358-02A-7-6

P03 @ 2.0' 43 25 59 63 66 68 70 75 80 81 89 97 98 99 100 23-0358-03A-7-6

P04 @ 2.0' 36 18 36 40 45 48 51 58 65 67 79 92 95 99 100 23-0358-04A-6

P05 @ 2.0' 38 21 81 81 82 82 83 83 83 83 83 85 89 91 94 96 98 100 23-0358-05A-6

P06 @ 2.0' 43 23 77 82 87 89 91 94 95 96 97 98 100 23-0358-06A-7-6

P05 @ 6" 40 21 33 35 37 38 38 40 41 41 42 46 48 52 61 69 89 100 23-0358-13A-2-6 www.wspcom

File: Supplier: Other:Email:Distribution: Client:

WSP USA

4221 Balloon Park Rd NE

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: June 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 1 Lab #: 23-0358-02

Sampled By: Jeffrey Mann Date Sampled: 5/22/2023

Color & Type of Material:

Sample Source: P02 @ 2.0' Project Manager: Jeffrey Mann SOILS / AGGREGATES

(ASTM D2844-18)

R-Value at 300psi: 4

Specimen Id.

Moisture (%): 16.7% Compactor Pressure (psi): 12 Specimen Height (in): 2.50 Dry Density (pcf): 113.8 Horizontal Pressure @ 1000lbs (psi): 61 Horizontal Pressure @ 2000lbs (psi): 139 Displacement: 3.34 Expansion Pressure (psi): 1.473 Exudation Pressure (psi): 502 R-Value: 10

18.2%

2.50 109.1

4.16 0.150

19.2%

2.50 107.9

4.22

0.000

A B C

RESISTANCE R-VALUE AND EXPANSION PRESSURE OF COMPACTED SOILS

050100150200250300350400450500550600650700750800

R- Va lue

Exudation Pressure (psi)

Reviewed By:_______________________________________

4221 Balloon Park Rd NE Albuquerque, NM 87109 Tel 5058211801 www.wsp.com

Distribution: File: Supplier:Client: Other:Email:

WSP USA

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: June 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 1 Lab #: 23-0358-03

Sampled By: Jeffrey Mann Date Sampled: 5/22/2023

Color & Type of Material:

Sample Source: P03 @ 2.0' Project Manager: Jeffrey Mann SOILS / AGGREGATES

(ASTM D2844-18)

R-Value at 300psi: 12

Specimen Id.

Moisture (%): 13.1% Compactor Pressure (psi): 120 Specimen Height (in): 2.50 Dry Density (pcf): 105.9 Horizontal Pressure @ 1000lbs (psi): 47 Horizontal Pressure @ 2000lbs (psi): 118 Displacement: 3.29 Expansion Pressure (psi): 2.375 Exudation Pressure (psi): 648 R-Value: 21

14.7% 2.50 107.2

3.31 1.955

16.3%

2.50 106.7

3.69

0.150

A B C

RESISTANCE R-VALUE AND EXPANSION PRESSURE OF COMPACTED SOILS

050100150200250300350400450500550600650700750800

R- Va lue

Exudation Pressure (psi)

Reviewed By:_______________________________________

4221 Balloon Park Rd NE Albuquerque, NM 87109 Tel 5058211801 www.wsp.com

Distribution: File: Supplier:Client: Other:Email:

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: June 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 1 Lab #: 23-0358-05

Sampled By: Jeffrey Mann Date Sampled: 5/22/2023

Color & Type of Material:

Sample Source: P05 @ 2.0' Project Manager: Jeffrey Mann SOILS / AGGREGATES

(ASTM D2844-18)

R-Value at 300psi: 5

Specimen Id.

Moisture (%): 17.2% Compactor Pressure (psi): 95 Specimen Height (in): 2.50 Dry Density (pcf): 107.4 Horizontal Pressure @ 1000lbs (psi): 60 Horizontal Pressure @ 2000lbs (psi): 144 Displacement: 4.13 Expansion Pressure (psi): 0.992 Exudation Pressure (psi): 399 R-Value: 6

18.5%

2.50 106.8

4.22 0.421

20.4%

2.50 105.7

4.29

0.000

A B C

RESISTANCE R-VALUE AND EXPANSION PRESSURE OF COMPACTED SOILS

050100150200250300350400450500550600650700750800

R- Va lue

Exudation Pressure (psi)

Reviewed By:_______________________________________

4221 Balloon Park Rd NE Albuquerque, NM 87109 Tel 5058211801 www.wsp.com

Distribution: File: Supplier:Client: Other:Email:

Laboratory Analysis Report Report: 947254

Reported: 7/10/2023 Received: 7/6/2023

PO: U00440010U

WSP USA Environment & Infrastructure Inc.

Jesse Boam 8519 Jefferson NE Albuquerque, NM 87113

Project: 73012219.10Lab Number Sample ID 947254-1 23-0444-01 P02 (2.5')

Test Parameter Test Method Result. Units Chloride AASHTO T291 14 ppm Sulfate AASHTO T290 6 ppmLab Number Sample ID

947254-2 23-0444-02 P03 (2.5')

Test Parameter Test Method Result. Units Chloride AASHTO T291 < 3 ppm Sulfate AASHTO T290 8 ppm

3540 E Corona Ave, Phoenix AZ 85040 | 602-454-2376 (Office) Page 1 of 1

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: July 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 2 Lab #: 23-0444-01

Sampled By: Jeff Mann Date Sampled:

Visual Description of Material:

Light Brown Clayey Sand, some gravel

Sample Source: P02 @ 2.5' Project Manager: Jeffrey Mann SOILS / AGGREGATES pH of Soils (ASTM D4972)

Method Used: A pH Value Tested In Water: 7.8

Reviewed By:_________________________________________ www.wsp.com

Distribution: File: Supplier:Client: Other:Email:

WSP USA

4221 Balloon Park Rd NE Albuquerque, NM 87109

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: July 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 2 Lab #: 23-0444-02

Sampled By: Jeff Mann Date Sampled:

Visual Description of Material:

Light Brown Clayey Sand, some gravel

Sample Source: P03 @ 2.5' Project Manager: Jeffrey Mann SOILS / AGGREGATES pH of Soils (ASTM D4972)

Method Used: A pH Value Tested In Water: 7.8

Reviewed By:_________________________________________ www.wsp.com

Distribution: File: Supplier:Client: Other:Email:

WSP USA

4221 Balloon Park Rd NE Albuquerque, NM 87109

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: July 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 2 Lab #: 23-0444-01

Sampled By: Jeff Mann Date Sampled:

Visual Description of Material:

Light Brown Clayey Sand, some gravel

Sample Source: P02 @ 2.5' Project Manager: Jeffrey Mann SOILS / AGGREGATES

Soil Resistivity: 2000

Determining Soil Resistivity Using the Two-Electrode Soil Box Method (ASTM G187-20)

Ωcm

Reviewed By:_________________________________________ www.wsp.com

File: Supplier: Other:Email:Distribution: Client:

WSP USA

4221 Balloon Park Rd NE

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: July 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 2 Lab #: 23-0444-02

Sampled By: Jeff Mann Date Sampled:

Visual Description of Material:

Light Brown Clayey Sand, some gravel

Sample Source: P03 @ 2.5' Project Manager: Jeffrey Mann SOILS / AGGREGATES

Soil Resistivity: 2000

Determining Soil Resistivity Using the Two-Electrode Soil Box Method (ASTM G187-20)

Ωcm

Reviewed By:_________________________________________ www.wsp.com

File: Supplier: Other:Email:Distribution: Client:

WSP USA

4221 Balloon Park Rd NE Albuquerque, NM 87109

Lakewood, CO 80228

Attn: Tammy Eggers

Report Date: June 07, 2023

Project Name: CFL CO FLAP LPL10(1) Lake Nighthorse Access Road

Project #: 73012219

Durango, CO

Work Order #: 1 Sampled By: Jeffrey Mann

Date Sampled: 5/22/2023

Project Manager: Jeffrey Mann SOILS / AGGREGATES

Lab # Color & Type of Material Sample Source Test

Method

Oven Temp.

(C)

Moisture

Dry Density (pcf)

Report #: 2531

Mass less than Min

Req.

Material Type *

MOISTURE CONTENT OF SOIL (ASTM D2216-19) AND IN-SITU DENSITY

23-0358-01 P01 @ 2.0' B 110 13.3 23-0358-02 P02 @ 2.0' B 110 15.6 23-0358-03 P03 @ 2.0' B 110 12.2 23-0358-04 P04 @ 2.0' B 110 10.9 23-0358-05 P05 @ 2.0' B 110 13.9 23-0358-06 P06 @ 2.0' B 110 15.9 23-0358-07 P01 @ 5.0' B 110 7.3 23-0358-08 P02 @ 5.0' B 110 12.5 23-0358-09 P03 @ 5.0' B 110 15.9 23-0358-10 P04 @ 5.0' B 110 9.0 23-0358-11 P05 @ 5.0' B 110 14.1 23-0358-12 P06 @ 5.0' B 110 11.6 23-0358-13 P05 @ 6" B 110 6.9 www.wsp.com

File: Supplier: Other:Email:

*Sample contains more than one type of material.

Distribution: Client:

WSP USA

4221 Balloon Park Rd NE

FHWA Central Federal Lands Highway Division

WSP

October 2024

D PAVEMENT

DESIGN

CALCULATIONS

Project: Date:

Location:

Pavement Section: By:

AASHTO Equation for Flexible Pavements

Design ESAL's, W18 50,000 (Equivalent Single Axle Loads)

Reliability, R (%) 75 Combined Standard Error, SO 0.49

Initial Serviceability Index, pi 4.2

Final Serviceability Index, pt 2

Subgrade Resilient Modulus, MR (psi) 4885

Standard Normal Deviate, ZR -0.674 Change in Present Serviceability Index, ΔPSI 2.2

Structural Number, SN 2.10 2.20 2.30

Equation Components A 4.0688855 4.1979438 4.3230305 B -0.0889411 -0.0889411 -0.0889411 C 3.4821242 3.0138998 2.6280759 D 0.4881658 0.4881658 0.4881658

Allowable ESAL's 34,002 45,352 59,890

Minimum Required Structural Number, SN 2.23

Recommended Structural Number, SN 2.3

Flexible Pavement Design based on 1993 AASHTO Design Chart for Flexible Pavements

4/24/2024

JSM

Lake Nighthorse Access Road

Lake Nighthorse Access Road

Lake Nighthorse Access Road

A

D

B

C

10,000

20,000

30,000

40,000

50,000

60,000

70,000

2.00 2.50

ES

AL

s

Pavement Thickness, D (in.)

ESAL - Thickness Relationship

Print Date: 4/24/2024 Flexible Pavt Design - 93 AASHTO FINAL DESIGN

HMA Pavement Section Based on Layer Coeffients

Scenario: Rehabilitation Layer

Material Coefficient New HMA 0.44

FDR-Cement 0.19

Design Sn: 2.23 New HMA FDR-Cement

3.35 4

2.92 5

2.48 6

2.05 7

1.62 8

1.19 9

0.76 10

0.33 11 -0.11 12

Use 3 5 Sn= 2.27

Project: Date:

Location:

Pavement Section: By:

AASHTO Equation for Flexible Pavements

Design ESAL's, W18 50,000 (Equivalent Single Axle Loads)

Reliability, R (%) 75 Combined Standard Error, SO 0.49

Initial Serviceability Index, pi 4.2

Final Serviceability Index, pt 2

Subgrade Resilient Modulus, MR (psi) 4885

Standard Normal Deviate, ZR -0.674 Change in Present Serviceability Index, ΔPSI 2.2

Structural Number, SN 2.10 2.20 2.30

Equation Components A 4.0688855 4.1979438 4.3230305 B -0.0889411 -0.0889411 -0.0889411 C 3.4821242 3.0138998 2.6280759 D 0.4881658 0.4881658 0.4881658

Allowable ESAL's 34,002 45,352 59,890

Minimum Required Structural Number, SN 2.23

Recommended Structural Number, SN 2.4

Flexible Pavement Design based on 1993 AASHTO Design Chart for Flexible Pavements

4/24/2024

JSM

Lake Nighthorse Gravel Parking Lot

Lake Nighthorse Gravel Parking Lot

Lake Nighthorse Gravel Parking Lot

A

D

B

C

10,000

20,000

30,000

40,000

50,000

60,000

70,000

2.00 2.50

ES

AL

s

Pavement Thickness, D (in.)

ESAL - Thickness Relationship

Print Date: 4/24/2024 Flexible Pavt Design - 93 AASHTO FINAL DESIGN Gravel Parking Lot

HMA Pavement Section Based on Layer Coeffients

Scenario: Rehabilitation Layer

Material Coefficient New HMA 0.44

UTBC 0.12

Subbase 0.1

Design Sn: 2.23 New HMA UTBC Subbase

2.62 4 6

2.35 5 6

2.08 6 6

1.80 7 6

1.53 8 6

1.26 9 6

0.98 10 6

2.08 6 6

2.08 6 6

1.80 7 6

1.80 7 6

1.80 7 6

1.53 8 6

1.53 8 6

1.53 8 6

1.26 9 6

1.26 9 6

1.26 9 6

Use 3 4 6 Sn= 2.4