mt-a2013018_Pavement_Report.pdf

PAVEMENT REPORT

MT Phillips 201(1) Old Highway 2 and Bridge Restoration

IDIQ Contract No. DTFH70-10-D-00016 Task Order No. T-14-005

Project 14-3206G

WFLHD Geotechnical Report 07-16

Submitted by

2511 Holman Avenue P. O. Box 80190

Billings, Montana 59108-0910

Prepared for

Federal Highway Administration Western Federal Lands Highway Division

610 E 5th Street Vancouver, Washington 98661

On behalf of

Robert Peccia & Associates P. O. Box 5653

Helena, Montana 59604-5653

May 20, 2015

Table of Contents

Description Page

A. Introduction

A.1. Project Description A.2. Scope of Services and Background

B. Review of Available Information and Reconnaissance

B.1. General Site Topography/Geologic Conditions/Climate B.2. Pavement Conditions B.3. Drilling and Sampling B.4. Results

C. Laboratory Testing Program/Procedures

D. Analysis/Recommendations

D.1. Discussion D.2. Cut Slopes D.3. Fill Slopes and Embankments D.4. Drainage D.5. Pavement Analysis D.6. Required Pavement Section D.7. FDR with Additional Aggregate D.8. FDR with CTB D.9. Cold In-Place Recycling D.10. Summary of Pavement Sections D.11. Chip Seal D.12. Culverts D.13. Dodson South Canal Bridge

E. General Recommendations

E.1. Basis of Recommendations E.2. Review of Design E.3. Groundwater Fluctuations E.4. Use of Report E.5. Level of Care

Tables

1 Existing Pavement and Anticipated Subgrade Conditions 2 Test Methods 3 Anticipated Extents of Unstable Subgrades 4 Summary of Pavement Sections 5 Extents of Crack Seal and Subexcavation in Chip Seal Portion of the Project

Table of Contents (continued)

Appendix 1 Vicinity Map Geologic Map Preliminary Plans and Profile Sheets with Boring Locations (10 sheets)

Appendix 2

Boring Photos (6 sheets) Descriptive Terminology – Soil Log of Boring Sheets ST-1 through ST-11 Pavement Core Photos (6 sheets)

Appendix 3

Pavement Condition Photos (8 sheets) Design CBR Value Worksheet MDT Traffic Data Map (4 sheets) DARWinTM Output (5 sheets)

Appendix 4 Laboratory Test Results (14 sheets) Summary of Corrosion Test Results

Robert Peccia & Associates May 20, 2015 Project 14-3206G Page 1

A. Introduction

A.1. Project Description The proposed project is intended to rehabilitate Old Highway 2 from the intersection with US Highway 2, then extending east approximately 3 1/2 miles to the intersection of the Bowdoin Road. The project corridor then continues northeast to the entrance to the Bowdoin National Wildlife Refuge (NWR) with a chip seal. The rehabilitation portion of the project begins at conceptual design Station 10+00 and ends at about Station 206+00 about 1/4 mile east of the Old Highway 2 intersection with Bowdoin Road. A surfacing only chip seal is then planned from about Station 206+00 eastward to the intersection at the Bowdoin NWR access road. A chip seal is also being considered for the Bowdoin NWR access road and parking lot, as well as the paved trail surrounding the display pond. New culverts are planned along the rehabilitation portion of the project. The intersection with existing US Highway 2 and Bowdoin Road may be realigned to improve truck access and turning. A Vicinity Map is included in Appendix 1.

A.2. Scope of Services and Background A preliminary field reconnaissance was performed by our personnel on April 22 and 23, 2014, along the project corridor. The initial reconnaissance was limited to visual and geologic assessment of the full project alignment, but no subsurface investigation or testing was performed at that time. The rehabilitation portion was closely observed, paying particular attention to surface defects and drainage.

Reconnaissance of the Dodson South Canal Bridge was performed to evaluate drill rig access. We also observed the pavement surface along the chip-seal portion of the project.

After completing the reconnaissance, a Geotechnical Reconnaissance Memorandum dated September 15, 2014, was prepared providing preliminary opinions related to existing pavement condition and probable causes of wide-spread pavement failures. Preliminary recommendations for pavement rehabilitation, and a proposed program for geotechnical drilling were also addressed.

A geotechnical investigation plan was then submitted on September 15, 2014. After receiving approval, another reconnaissance was performed by our engineers on September 23, 2014. During this trip, the borings were staked, photographed (attached), and GPS coordinates recorded. We also observed pavement conditions along the Bowdoin NWR access road, parking lot, and display pond trail.

The geotechnical drilling program was then performed by SK Geotechnical between the dates of October 6 and 16, 2014. The drilling consisted of 13 soil borings along the project corridor at select locations.

Eleven were performed along the rehabilitation portion of the project and two deeper borings were performed for the Dodson South Canal Bridge structure.

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After completing the drilling, samples from the borings were returned to our laboratory for testing.

Laboratory testing for the pavement borings generally consisted of classification tests, three-point California bearing ratio, specific gravity, and corrosion tests. After completing the laboratory testing, geotechnical analysis of alternative pavement sections including full-depth reclamation and total reconstruction was performed. The results of this analysis as well as other geotechnical recommendations related to the project are contained in this report. Analysis and recommendations related to the Dodson South Canal Bridge will be submitted in a separate report.

B. Review of Available Information and Reconnaissance

B.1. General Site Topography/Geologic Conditions/Climate The project is located in relatively flat, rolling terrain and is primarily used by local farmers and ranchers as well as visitors to the Bowdoin NWR. The area surrounding the project typically sees a climate with cold, average moisture winters, and warm, relatively dry summers. The area on average receives approximately 13 inches of rain and 26 inches of snowfall per year. The wetter months are typically from October to June when snowmelt and spring rains cause run-off.

Observations at the site and review of readily available geologic literature indicate the project area is located within a depositional environmental including alluvium, colluvium, and glacial deposits with outcrops of glacial ice contact deposits. This portion of Old Highway 2 is situated in the Milk River valley, which is actually the ancient valley of the Missouri River. Continental glaciers during past ice ages actually shifted the Missouri River about 60 miles south to its current location, leaving this broad valley currently occupied by the Milk River. The valley is used for significant agricultural purposes growing alfalfa, hay, wheat, and many other important crops. The following stratigraphic units were identified along the project as noted by the Geologic Map of the Malta 30' x 60' Quadrangle. A portion of this map is shown on the Geologic Map in Appendix 1.

Qac: Alluvium-Colluvium, includes deposits and alluvial fans and on alluvial terraces; may include glacial outwash Qg: Glacial Deposits, typically glacial till and glacial outwash Qgi: Glacial Ice-Contact Deposits Kcl: Claggett Shale, upper Cretaceous

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B.2. Pavement Conditions

B.2.a. General. It is our opinion the rehabilitation portion of the existing pavement from Station 10+00 to about Station 206+00 is in very poor condition. From Station 206+00 to the Bowdoin NWR access road, we judged the pavement to be in fair condition due to an overlay project performed in 2007 (FHWA Project MTRRPDOWD900(1)). The Bowdoin NWR access road and parking lot are in fair to good condition, while the display pond trail is in fair condition. Our observations of the pavement are described in more detail below as well as the photographs in Appendix 3.

B.2.b. Rehabilitation Alignment from Station 10+00 to 206+00. Photographs 1 through 16 in Appendix 3 show the very poor pavement condition for the rehabilitation portion of the project. The observations are summarized below.

• Extensive longitudinal and transverse cracking in the existing pavement. Longitudinal cracks 1 to 2 feet from the pavement edge and along the centerline throughout the alignment. Transverse cracks throughout typically ranging from 5 to 10 feet, but as close as 2 to 6 feet.

• Extensive patching over multiple years has occurred throughout the alignment and patched areas range from 2 to 3 feet in diameter (pot holes) up to half-lane and full-lane widths for several hundred feet. Numerous pot holes and failed pavement areas were observed along the alignment indicating additional patching is needed very soon.

• Significant alligator cracking of the pavement surface was observed which indicates pavement failure. We estimate approximately 75 percent of the pavement surface within the rehabilitation alignment has alligator cracking.

• Significant pavement edge failure is occurring as well. We estimate up to 30 percent of the pavement edges are failing.

• Numerous areas of poor drainage of surface water were observed along the alignment primarily associated with lack of crown and inadequate borrow ditches. The most significant areas of inherent poor drainage occurred from about Station 93+00 to 116+50, 146+50 to 150+00, and 175+00 to 177+00.

• The pavement in Bowdoin Road intersecting with Old Highway 2 at about Station 190+00 also had significant alligator cracking, edge failures, and longitudinal/transverse cracking.

B.2.c. Chip Seal Alignment from Station 206+00 to Bowdoin NWR Access Road. Photographs 17 through 21 in Appendix 3 show the fair pavement condition in this portion of the project, which will be chip sealed.

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• Minor longitudinal cracks observed along about 50 percent of the pavement. Transverse cracks throughout typically spaced at 25-foot intervals. Cracks 1/8- to 1/4-inch wide.

• Occasional patches where the patch is in good condition.

• Isolated areas of alligator cracking.

B.2.d. NWR Access Road. Photographs 21 through 23 in Appendix 3 show the fair pavement condition in this portion of the project.

• Minor longitudinal cracks observed along about 50 percent of the pavement. Minor transverse cracks throughout typically spaced at 30-foot intervals. Cracks 1/8- to 1/4-inch wide.

• Minor areas of alligator cracking along access road approximately 10 to 30 square feet in size.

• Minor control joint separation in access road indicating pavement is fairly old.

B.2.e. NWR Parking Lot. Photographs 24 and 25 show the good pavement condition in the existing parking lot.

• Minor longitudinal and transverse cracks observed in parking lot, 1/8- to 1/4-inch wide.

• Rough texture on surface, primarily associated with segregation during paving.

• Very minor joint separation in isolated areas.

B.2.f. NWR Display Pond Trail. Photographs 26 through 32 in Appendix 3 show the fair pavement condition in this portion of the project.

• Recently had a seal coat applied, likely covering some defects and/or deterioration.

• Minor areas of edge failure, may be due to skid steer or pickup driving along trail.

• Isolated areas where grass was growing through paved trail.

• Pavement failure occurring behind posts situated between access road and trail. Tree roots are heaving pavement causing cracking.

• Isolated transverse cracks and longitudinal cracks in pavement, 1/8- to 1/4-inch wide.

B.3. Drilling and Sampling Borings ST-1 through ST-11 were performed along the rehabilitation portion of the project as shown on the Plan and Profile sheets in Appendix 1. At all of the pavement borings, the existing asphalt pavement

Project 14-3206G Page 5 was cored and thicknesses were measured and noted on the boring logs. If present, underlying gravel base thicknesses were measured and 1-gallon size bag samples collected for further laboratory testing. In seven of the 11 pavement borings, large bulk subgrade samples were obtained and returned to our laboratory for testing. Photographs of the borings and pavement cores are included in Appendix 2.

The borings were performed on the date indicated on the boring logs with a truck-mounted core and auger CME 75HT drill rig. The 11 pavement borings were generally extended to a depth of 5 feet below existing pavement. Seven bag samples of the pavement subgrade were collected as well as base course samples from each boring, if present, were collected. Penetration tests were performed at 2 1/2-foot intervals to the borings' termination depth.

B.4. Results

B.4.a. Logs. Log of Boring sheets indicating the depth and identification of the various soil strata, the penetration resistances, laboratory test data, and water level information are attached. It should be noted, the depths shown as boundaries between the strata are only approximate. The actual changes may be transitions and the depths of the changes vary between borings.

B.4.b. Summary Table. Table 1 following this page summarizes the existing pavement and subgrade conditions at Borings ST-1 through ST-11 along the rehabilitation portion of the project. The existing pavement and subgrade conditions are discussed in more detail below.

B.4.c. Existing Pavement. Using all of the borings except Boring ST-10, which was performed on Bowdoin Road, the average existing pavement section is indicated below.

Existing Plant Mix Surfacing 4½" Existing Base/Subbase Course 4¼" Total Thickness 8¾"

Although layer thicknesses varied, three of the soil borings performed for the rehabilitation portion of the project encountered a thinner than average section ranging from only 6 to 7 1/4 inches thick.

B.4.d. Subgrade. The boring logs in Appendix 2 outline more details about the soil stratum encountered by each boring. The soils encountered by the borings along the alignment consisted of primarily lean clay with sand and lean clay. As indicated in Table 1, these clays were generally found to be wet, and mostly range from near optimum moisture content (OMC) to 11 percent above OMC, but primarily ranged from 4 to 7 percent above OMC. Penetration resistances indicated the clays were primarily soft to firm.

Robert Peccia & Associates February 12, 2015 Project 14-3206G Page 6

Table 1. Existing Pavement and Anticipated Subgrade Conditions Boring ST-1 ST-2 ST-3 ST-4 ST-5 ST-6 ST-7 ST-8 ST-9 ST-10 ST-11

Date Drilled 100/6/2014 10/06/2014 100/6/2014 10/06/2014 10/07/2014 10/08/2014 10/08/2014 10/08/2014 10/08/2014 10/08/2014 10/08/2014

Station, Offset 10+61.77, 301.9' Rt

33+78.48, 6.1' Lt

59+74.35, 6.5' Rt

85+80.46, 6.3' Rt

115+59.20, 4.5' Rt

145+80.77, 3.0' Lt

159+43.23, 4.6' Rt

172+66.84, 3.9' Lt

191+19.70, 6.4' Lt

190+45.46, 50.6' Rt

205+40.59, 5.2' Rt

Existing PMS 4" 3" 3" 2¾" 4¼" 4¼" 4½" 5" 9" 2" 12½"

Existing Base/Subbase 6" 5" 3½" 7¼" 6½" 3" 1½" 4¼" 1" 0" 1"

Total Thickness 10" 8" 6½" 10" 10¾" 7¼" 6" 9¼" 10" 2" 13½"

Subgrade(1)

Description Lean Clay with Sand

Lean Clay with Sand

Lean Clay with Sand

Lean Clay with Sand Lean Clay Lean Clay with Sand Lean Clay with Sand

Lean Clay with Sand

Lean Clay with Sand

Fill: Poorly Graded

Gravel with Sand

Lean Clay with Sand

ASTM Class CL CL CL CL CL CL CL CL CL Fill: GP CL

N-Values 7, 7 9, 6 5, 9 4, 8 8, 8 7 7, 3 6, 4 4, 3 15 5, 5

Consistency Firm Firm to Stiff Firm to Stiff Soft to Firm Firm Firm Firm to Soft Firm to Soft Soft Medium Dense Firm

Moisture Content, % 17.5, 7.8 8.1, 9.7 11.8, 16.3 13.1, 13.7 10.0, 25.7 22.7, 24.4 19.2, 26.9 17.0, 23.8 19.4, 20.8 5.2 14.9, 27.4

Approximate Optimum Moisture Content, %

11.8 16(2) 13.2 16(2) 18.8 18.2 16(2) 18.5 16.7 7(2) 16 (2)

Risk of Subgrade Failure During Total Reconstruction

High Low Medium Medium High High High High High Low High

Geosynthetic Recommended Yes No Yes No Yes Yes Yes Yes Yes No Yes (1)Anticipated subgrade that will be present beneath the proposed pavement section.

(2)OMC is an estimated value based on similar soils in the area and engineering judgment.

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B.4.e. Groundwater Observations. Groundwater was encountered in Boring ST-10 at a depth of 6 feet, and in the bridge borings at depths of 8 and 11 feet. Boring ST-10 was performed at the intersection of Old Highway 2 and Bowdoin Road. We wish to point out that the period of observation was relatively short (about 10 minutes) and it could require a longer period of observation for groundwater levels to stabilize in these types of clay soils. Fluctuation of groundwater levels can and will occur in the project area, especially when considering spring run-off, snow fall, poor drainage, and irrigation of local agricultural lands.

C. Laboratory Testing Program/Procedures After completion of the pavement borings, the samples were returned to our material testing laboratory.

Laboratory tests were performed in accordance with AASHTO standards. Laboratory tests were performed on bulk subgrade bag samples, split-spoon samples, and Shelby tube samples. Representative samples were chosen for our laboratory testing program. Plasticity index, moisture content, sieve analysis, and corrosion tests were performed on representative bulk subgrade, split-spoon, and Shelby tube samples. Additionally, plasticity index, moisture content, sieve analysis, specific gravity, California bearing ratio (CBR), and standard Proctor tests were performed on selected bulk subgrade bag samples.

The complete laboratory test results are included in Appendix 4. The test methods are outlined in Table 2 below.

Table 2. Test Methods

Test Name AASHTO Standard

Particle Size Analysis to 0.02 mm T88

Plasticity Index (Atterberg Limits) T89/T90

Specific Gravity T100

California Bearing Ratio, 300 psi Exudation T193

Soil Classification M145

Sieve Analysis T11/T27

Natural Moisture Content T265

Moisture-Density, Standard Proctor T99 pH of Soil T289

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D. Analysis/Recommendations

D.1. Discussion Our pavement observations in the rehabilitation portion of the project from Station 10+00 to 206+00 indicated the pavement was in very poor condition. Alligator cracking was observed along about 75 percent of the pavement surface with the remaining area primarily consisting of patches, some of which were also failing. The distress is a clear indication the existing pavement is too old and too thin.

Rehabilitation by pulverization and/or total reconstruction is therefore recommended. Extreme care will be required during construction due to the underlying wet, soft lean clay subgrade, which is discussed in more detail later in this report.

It is our understanding a chip seal restoration is planned from Station 206+00 to the Bowdoin NWR access road, as well as the Bowdoin NWR access road, parking lot, and display pond trail. Geotechnical exploration of these pavements was not performed, and the pavement conditions were discussed previously in this report. In our opinion, crack sealing followed by a chip seal appears appropriate.

Consideration can be given to identifying isolated areas of alligator cracking along these alignments, then performing subexcavation, however, the cost may not be justified.

D.2. Cut Slopes No cut slopes are currently planned for the proposed project, as we understand it.

D.3. Fill Slopes and Embankments Some fill will be needed to raise grades along the project, particularly near the beginning of the project at the intersection of US Highway 2 and Old Highway 2 and at the bridge approaches. We recommend the existing pavement be removed (or pulverized) then fill be placed up to subgrade. Fill can consist of Unclassified Borrow or Select Borrow, depending on the thickness. The required pavement section should then be placed on top of the fill in these areas. It is our opinion that 1 vertical:2 horizontal (1:2) fill slopes can be used, however, we would prefer 1:3 slopes for maintenance operations and safety.

D.4. Drainage Numerous areas of poor surface water drainage were observed along the alignment primarily associated with the lack of crown, inadequate borrow ditches, and longitudinal slope along the ditch bottoms. The most significant areas of inherent poor drainage occurred from about Station 90+00 to 114+00, 143+00 to 147+00, and 172+00 to 175+00. Based on these observations and the general topography, we judged the drainage to generally be poor. New culverts or culvert extensions will be installed along the rehabilitation portion of the project.

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D.5. Pavement Analysis

D.5.a. Traffic Analysis. Traffic data for the alignment was not provided for our pavement thickness design. We used the Montana Department of Transportation (MDT) Interactive Traffic Map found on their website to obtain a present AADT along Old Highway 2 for 2013. The following parameters were entered into DARWinTM, which is a pavement design software based on the 1993 Pavement Design Manual to perform a simple ESAL calculation.

Initial performance (years): 20 Initial two-way daily traffic (ADT): 220 Percent heavy trucks (ADT) FHWA Class 5 or greater: 3 Number of lanes in design direction: 1 Percent of all trucks in design lane (%): 60 Percent trucks in design direction (%): 100 Average initial truck factor (ESALs/truck): 1.1 Annual truck factor growth rate (%): 0.0 Annual truck volume growth rate (%): 2.0 Growth: simple

Total calculated cumulative ESAL: 37,866

These design ESALs are based on a 20-year design life. Chapter 11, Pages 11 and 12 of the WFLHD Project Development and Design Manual (PDDM) indicates that if calculated ESAL values are less than 50,000 ESALs, then a minimum of 50,000 ESALs is to be used for design of pavement structures.

Therefore, 50,000 ESALs were used for our pavement design.

D.5.b. Methodology. The pavement thickness design was also analyzed using DARWin. WFLHD's design parameters from the PDDM were incorporated. Seven CBR tests were also performed on bulk subgrade samples. The results of the CBR tests ranged from 1.5 to 3.9 with an average CBR value of 2.6.

Using equations provided in the AASHTO 1993 Pavement Design Manual, we calculated an equivalent roadbed resilient modulus of 3,900 pounds per square inch (psi) for the existing subgrade based on the average CBR value.

The following design input parameters were used to evaluate appropriate pavement sections.

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• 18-kip ESALs over initial performance: 50,000

• Initial Serviceability: 4.2

• Terminal Serviceability: 2.0

• Reliability Level: 75%

• Standard Deviation: 0.49

• Roadbed Resilient Modulus (psi): 3,900

Based on our analysis, we calculated a Structural Number (SN) of 2.43 will be required to support a 20-year pavement design for the proposed alignment. We analyzed numerous pavement section alternatives for this project as indicated below. Each of these pavement sections is then discussed in more detail later in this report.

1. Required Pavement Section: Conventional Select Borrow and cement-treated base (CTB) sections, primarily to be used in fill areas.

2. Full Depth Reclamation (FDR) with Additional Aggregate: FDR is recommended to take advantage of the existing pavement and aggregate along the rehabilitation portion of the project.

Because the existing pavement and aggregate is too thin, however, additional aggregate will be necessary for this approach. Also, very soft subgrades will be encountered in some areas requiring a thicker subexcavation section.

3. FDR with Cement-Treated Base (CTB): FDR with CTB is another method to consider to take advantage of the existing pavement and base course along the alignment. Because the existing pavement is too thin, cement will need to be added during the reclamation process to provide a

CTB.

4. Cold In-Place Recycling: This option is primarily a surfacing rehabilitation approach requiring a specialized paving contractor to make the cold in-place pavement.

D.6. Required Pavement Section As previously indicated, we recommend providing a new pavement section (no recycled materials) for fill areas along the project. After the existing pavement has been removed or pulverized, fill can be placed up to subgrade elevation, then the following Select Borrow or CTB sections can be provided.

We recommend a Select Borrow section rather than a base course section because it is thicker and is more suited for areas with wet clay subgrades. The following Select Borrow section results in a SN of 2.49, exceeding the required minimum SN of 2.43. A separation geotextile is also recommended with this pavement section for long-term separation of the Select Borrow from the Unclassified Borrow, which could consist of recompacted on-site clays.

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Hot Mix Asphalt Pavement 3" Crushed Base Course, Grade D 4" Select Borrow 12" Class 1, Type A, Nonwoven Geotextile yes Total Thickness 19"

If FDR with CTB is selected for the project, then we recommend extending the CTB into the fill areas to provide a more uniform pavement section. The CTB section should be constructed of new materials (no recycled materials) as indicated below. This section results in a SN of 2.49, exceeding 2.43.

Hot Mix Asphalt Pavement 3" New Crushed Base CTB 7" Total Thickness 10"

D.7. FDR with Additional Aggregate

D.7.a. Recommended Thickness. The soil borings indicate there is not enough pavement structure present to meet the full depth reclamation approach. Therefore, additional crushed base course (CBC) will be required. We recommend adding 5 inches of CBC on top of the existing pavement prior to reclaiming/pulverizing. For this FDR option, we recommend pulverizing/reclaiming to a maximum depth of 6 inches below the existing pavement grade. When combined with the 5 inches of CBC, then pulverization/reclamation should be performed to a minimum depth of 11 inches. The reclaimed mixture should then be recompacted to specification followed by 3 inches of new asphalt pavement, resulting in the following pavement section.

Hot Mix Asphalt Pavement 3" Pulverized/Reclaimed Base Course 11" Existing Base Course (not disturbed) 2" Total Thickness 16"

This section results in a SN of 2.45, exceeding 2.43. The advantage of FDR is the reclaimer and other construction equipment primarily stays on top of the existing pavement reducing the risk of excessive subgrade disturbance by heavy rubber-tired construction equipment. Even so, some unstable areas should be anticipated, especially in the vicinity of Borings ST-6, ST-8, and ST-9. In these areas, a thicker section having subexcavation should be used in lieu of the full depth reclamation section.

D.7.b. Subexcavation Areas. FDR with additional aggregate will most likely be performed with conventional construction equipment, although light equipment would be the best approach. As previously indicated in Table 1, seven of the 11 borings encountered subgrades having a high risk of becoming unstable during construction activities with the conventional equipment. Table 3 below

Project 14-3206G Page 12 summarizes the extents of the alignment where unstable subgrades are anticipated, based on the borings, and a subexcavation section should be provided.

Table 3. Anticipated Extents of Unstable Subgrades

Station to Station Length (feet) 134+00 to 165+00 3,100 179+00 to 194+00 1,500

Total 4,600

We recommend providing the following pavement section for those extents indicated above as well as other areas identified during construction as directed by the ENGINEER.

Hot Mix Asphalt Pavement 3" Crushed Base Course, Grade D 5" Select Borrow 24" Class 1, Type A, Nonwoven Geotextile Yes Total Thickness 32"

We recommend the first lift of Select Borrow be placed by end-dumping methods having a thickness of 16 inches. We recommend the geotextile be installed in accordance with the manufacturer's specifications. Construction equipment used to haul off digout materials should be kept on the existing pavement whenever possible, to avoid excessive rubber-tired traffic on pulverized base course. The subexcavation should be performed with low pressure equipment, most likely a tracked excavator having a smooth-bladed bucket.

D.8. FDR with CTB

D.8.a. Discussion. CTB with new aggregates is commonly used on Montana Department of Transportation (MDT) projects. It is our understanding these pavement sections have been performing well. CTB projects comprised of existing pavement and base course, however, has been used on a very limited basis in Montana. We recognize this approach may be more cost effective for the roadway, but must emphasize that its use in Montana has been limited, and selecting qualified contractors is critical.

For this approach, cement treatment mix designs in accordance with standard specifications should be performed. We anticipate 4 to 6 percent cement by weight will be necessary to meet specifications, although project specific mix design(s) should be performed to determine cement content.

D.8.b. Recommended Thickness. Our analysis indicates 3 inches of new hot mix asphalt pavement placed over a minimum of 7 inches of recycled CTB results in a SN of 2.49, exceeding 2.43. However, Project 14-3206G Page 13 reshaping of the aggregate surface prior to paving is needed to improve the roadway width. When considering the reshaping and regrading, we anticipate the following reclamation along the project.

• Reclaiming/pulverizing the existing pavement, base course, and subgrade to 8 to 9 inches (3/4-inch minus material).

• Reshape and regrade to achieve required roadway width, adding new 3/4-inch crushed base as necessary to achieve grade.

• Apply 4 to 6 percent cement (hydrated, slurry cement preferred due to Malta winds) and reclaim/pulverize to 7 inches.

• Recompact CTB to specifications and allow for proper cure.

• Apply tack coat and sand blotter as necessary to top of CTB.

• Place 3 inches of hot mix asphalt pavement.

For this approach, the following pavement section will then be provided.

Reclaimed CTB 7" Total Thickness 10"

D.8.c. Thicker Cement-Treated Section for Unstable Areas. As previously indicated, approximately 4,600 feet or more of relatively unstable areas could be present along the alignment during reconstruction.

We believe CTB with FDR has lower construction equipment traffic than conventional approaches, therefore, the unstable areas could be less.

Repairing unstable areas when constructing CTB with FDR was discussed with a local contractor.

Although site conditions will dictate the best approach, the following general approach is recommended.

• Determine the extents of unstable areas by the following processes as determined by the

ENGINEER:

- While performing the first reclamation/pulverization pass, record areas where reclaimer gets bogged down, and

- After completing the first FDR pass, perform proof rolling on top of the reclaimed base with a loaded tandem axle dump truck or front-end loader. Where deflection of 1/2-inch or more occurs, area should be considered unstable.

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• In unstable areas only, perform a second pass with reclaimer to 14 inches with 3 percent cement to create a low-strength thicker lift for bridging.

• Compact and allow to cure. (We realize compacting 14 inches will be difficult, however, it will be better than what is there.)

• A third pass is then performed in conjunction with the remaining road, in this case to a depth of 7 inches with 4 to 6 percent hydrated cement, compact, allow to cure, then place new pavement surfacing.

This will then result in the following thicker cement-treated section in unstable areas.

Reclaimed CTB and Subgrade 14" Total Thickness 17"

D.9. Cold In-Place Recycling

D.9.a. Discussion. This approach rehabilitates the existing surfacing, reducing the risk of construction equipment creating unstable subgrades during construction, but is also not common in Montana. It is our understanding out-of-state contractors are needed for the cold in-place recycling, and they may not be interested in a 3 1/2-mile project, which is relatively small. Another major disadvantage is some of the existing pavement remains in place. Considerable cracks will therefore reflect through the new surfacing.

Also, this equipment is relatively heavy, and it is our opinion the risk of weak areas being encountered and the equipment becoming stuck during the recycling process is relatively high. Boring ST-3 is typical of one of these weak areas where all of the asphalt pavement will be removed, and the underlying base course relatively thin, and the subgrade weak.

D.9.b. Recommended Thickness. We recommend providing 3 inches of cold in-place recycled pavement followed by 3 inches of new hot mix resulting in a SN of 2.70. The following pavement section will be provided.

Hot Mix Asphalt Pavement 3" Cold In-Place Recycled Pavement 3" Existing Pavement (severely cracked) 1½" Average Existing Base Course 4¼" Average Total Thickness 11¾"

D.9.c. Unstable Areas. Although this approach primarily stays on top of the existing surfacing, there is a risk that construction equipment could break through the existing pavement as described above. In these areas, we recommend subexcavating the unstable area and reconstructing in accordance with

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Section D.7.b., Subexcavation Areas. The extent of these areas will have to be determined during construction by the ENGINEER.

D.10. Summary of Pavement Sections Table 4 below contains a summary of the pavement sections analyzed.

Table 4. Summary of Pavement Sections

Pavement Structure Surfacing Coefficient

Select Borrow Section

CTB Section

FDR with Additional Aggregate

Section

Cold In-Place Recycled Section

Hot Mix Asphalt Pavement 0.41 3" 3" 3" 3"

Cold In-Place Recycled Pavement 0.30 --- --- --- 3"

Existing Pavement 0.20 --- --- --- 1½"

Crushed Base Course 0.14 4" --- --- ---

Select Borrow 0.07 12" --- --- ---

Reclaimed Base Course 0.11 --- --- 11" ---

Existing Base Course 0.07 --- --- 2" 4¼"

New or Reclaimed CTB 0.20 --- 7" --- ---

Total Thickness 19" 10" 16" 11¾" Calculated SN* 2.49 2.49 2.45 2.70 *All options are based on 50,000 ESAL design value, required SN=2.43.

D.11. Chip Seal Chip sealing is planned from Station 206+00 eastward to the intersection at the Bowdoin NWR access road. It is also being considered along the Bowdoin NWR access road and parking lot, as well as display pond trail. Isolated areas of alligator cracking were observed in these alignments. To avoid premature failure of the chip seal, consideration can be given to identifying the alligator cracking areas, then performing a subexcavation prior to chip sealing.

Table 5 below summarizes the relative extent of crack sealing and subexcavation areas for the chip seal portion of the project.

Project 14-3206G Page 16

Table 5. Extents of Crack Seal and Subexcavation in Chip Seal Portion of the Project

Location/Extent Existing Cracks Subexcavation

Areas Longitudinal Transverse Total

Sta. 206+00 to 208+00 300' 25' c-c

20' x 200' 160' total

460' None

Sta. 208+00 to 223+00 2,300' 25' c-c

20' x 1,500' 1,200' total

3,500' Entire Length

5' x 1,500' down C.L.

Sta. 223+00 to 314+36 2,200' 25' c-c

20' x 9,136' 7,309' total

9,509' 4 Areas 10' x 25' each

NWR Access Road 500' 30' c-c

18' x 1,840' 1,104' total

1,604' 5 Areas 5' x 25' each

NWR Parking Lot 300' --- 300' None Totals 5,600' 9,773' 15,373'

We recommend providing the following pavement section in the subexcavation areas.

Crushed Base Course, Grade D 8" Select Borrow 16" Class 1, Type A, Nonwoven Geotextile Yes Total Thickness 27"

These extents are based on visual observations of the existing pavement. Specific crack mapping was not performed. The actual extents of crack sealing and subexcavation areas will need to be determined by the ENGINEER during construction. Unit costs for these items are recommended to permit adjustments during construction.

D.12. Culverts Wet, soft clay subgrades will be present beneath new culverts and/or culvert extensions. To provide a stable platform for the culvert, we recommend providing a Class 2 Type B nonwoven geotextile on the subgrade covered with 12 inches of CBC. Bedding can then be placed over the CBC to the bottom of the culvert. Groundwater could also be encountered, especially in the spring during run-off. Dewatering could be necessary.

Project 14-3206G Page 17

D.13. Dodson South Canal Bridge A separate geotechnical report will be submitted with our recommendations for the proposed Dodson South Canal Bridge.

E. General Recommendations

E.1. Basis of Recommendations The analyses and recommendations submitted in this report are based upon the data obtained from the soil borings performed at the locations indicated. Often, variations occur between these borings, the nature and extent of which do not become evident until additional exploration or construction is conducted. This is especially true for existing pavement thicknesses. A reevaluation of the recommendations in this report should be made after performing on-site observations during construction to note the characteristics of any variations. The variations may result in additional earthwork and pavement costs, and it is suggested a contingency be provided for this purpose.

It is recommended we be retained to perform the observation and testing program for the site preparation phase of this project. This will allow correlation of the soil conditions encountered during construction to the soil borings, and will provide continuity of professional responsibility.

E.2. Review of Design This report is based on the design of the proposed alignment as related to us for preparation of this report.

It is recommended we be retained to review the geotechnical and pavement aspects of the designs and specifications. With the review, we will evaluate whether any changes in design have affected the validity of the recommendations, and whether our recommendations have been correctly interpreted and implemented in the design and specifications.

E.3. Groundwater Fluctuations We made water level observations in the borings at the times and under the conditions stated on the boring logs. These data were interpreted in the text of this report. The period of observation was relatively short, and fluctuation in the groundwater level may occur due to rainfall, flooding, irrigation, spring thaw, drainage, and other seasonal and annual factors not evident at the time the observations were made. Design drawings and specifications and construction planning should recognize the possibility of fluctuations.

E.4. Use of Report This report is for the exclusive use of Robert Peccia & Associates and the Federal Highway Administration (FHA) to use to design the proposed improvements and prepare construction documents.

Project 14-3206G Page 18

In the absence of our written approval, we make no representation and assume no responsibility to other parties regarding this report. The data, analyses, and recommendations may not be appropriate for other structures or purposes. We recommend parties contemplating other structures or purposes contact us.

E.5. Level of Care Services performed by SK Geotechnical Corporation personnel for this project have been conducted with that level of care and skill ordinarily exercised by members of the profession currently practicing in this area under similar budget and time restraints. No warranty, expressed or implied, is made.

Appendix 1

VICINITY MAP

Pavement Report

MT Phillips 201(1), Old Highway 2 and Bridge Restoration Malta, Phillips County, Montana

Drawn by: DPH/SKG, Google Earth Date 1/5/2015

Project: 14-3206G

Scale: NTS FIGURE

Sheet 1 of 1 1

North

GEOLOGIC MAP

Pavement Report

MT Phillips 201(1), Old Highway 2 and Bridge Restoration Malta, Phillips County, Montana

Drawn by: DPH/SKG Date 1/5/2015

Project: 14-3206G

Scale: NTS FIGURE

Sheet 1 of 1 3

Project Start Project End

North

Qac = Alluvium – Colluvium Qg = Glacial Deposits Qgi = Glacial Ice-Contact Deposits Kcl = Claggett Shale

Reference: Montana Bureau of Mines and Geology, Geologic Map of the Malta 30' x 60' Quadrangle, Northeast Montana, Robert N. Bergantino, 1999

NO. 9081

NO. 9082 NO. 9083 NO. 9084 NO. 9085

NO. 9086

NO. 9087

NO. 90 88

ANCHOR POLE

GUY WIRE

GUY WIRE

GUY WIRE

W A R N I N G

B U R I E D

U T I L I T Y

GAS

W A R N I N G

B U R I E D

U T I L I T Y

FIBER

W A R N I N G

B U R I E D

U T I L I T Y

BURIED POWER

W A R N I N G

B U R I E D

U T I L I T Y

BURIED POWER

W A R N I N G

B U R I E D

U T I L I T Y

FIBER

W A R N I N G

B U R I E D

U T I L I T Y

GASPIPELINE

E L

E V

E L

E V

C

M P

E L

E V

24" CONC IN

E L

E V

C

O N

C R

E T

E

E L

E V

E L

E V

DELINEATOR

DELINEATOR

STOP

REDUCED S

PEED

HISTORIC POINT 1/2MI

C

O N

C R

E T

E

24" CSP

IS

A G

UES

S

FIB

ER L

OCATIO

N

IR

4RBR

IR

4RBR

WP 0-0X

EL. 0000.000

4RBR

,2

.4

-1.9981%

,2

.9

,2

.5

+1.1739

160’ VC

K = 50

,2

.9

.7

.0

P C

.9

P T

.4

D

R= 150.00’

T= 117.66’

L= 199.55’

D

R= 2,050.00’

T= 267.75’

L= 532.48’

POT 12

+73.0

P T

.3

P C

.9

P T

.4

PC 13+

38.80 e= 0.020

BH ST-1

MT D.3

Line to be constructed

Profile grade

Existing ground

U.S . Hi ghway

1.0 miles

Malta

Railroad

1:

:2

Culvert inlet/outlet ditch

Line to be constructed

PLAN AND PROFILE LEGEND:

ST

Typical inlet/outlet ditch

T

Structure transition railing

P ip e C u lv e r t

A p p r o a c h P ip e C u lv e r t

L

T

PHILLIPS 201(1)

10+00 15+00 20+00 25+00 30+00

N method 1

Roadway obliteration, 5A

P ip e C u lv e r t

P ip e C u lv e r t

A

R e m o v e

E x is ti n g

P ip e C u lv e r t

R

T

103.36’ LT

13+32.13 15,056 SQFT = 0.346 acres

Malta, MT 59538

1529 U.S. Highway 191 S

Sally Jane Ereaux

No Scale

CONNECTION DETAIL

surfacing asphalt

Existing section

See typical vertical joint

Sawcut for

.7

E=2 372 396.22

N=1 502 780.95

12+90.72

BRIDGE RESTORATION

OLD HIGHWAY 2 AND

MT PHILLIPS 201(1)

BEGIN REHABILITATION

See sheet D.1 for complete excavation and embankment totals.

Excavation volumes shown do not include conserved topsoil quantities.

type Tangent Terminal section, D

48.42’ LT

14+66.26

CUYD

EXC.

CUYD

EMB.

STATE PROJECT

NUMBER

SHEET

P

M

M a y

I n t_ ft

D

C F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D A .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b y

FAP 142-A

TT

UP

W A R N I N G

B U R I E D

U T I L I T Y

W A R N I N G

B U R I E D

U T I L I T Y

W A R N I N G

B U R I E D

U T I L I T Y

E L

E V

E L

E V

E L

E V

E L

E V

ELEV 2259.83 12" CMP

ELEV 2259.63

ELEV 2258.14

ELEV 2258.22

16" CONCRETE

ELEV 2259.07

ELEV 2259.01

12" CMP

DELINEATOR

C

C

O N

C R

E T

E

P C

.6

P T

.2

BH ST-2

BH ST-3

P C

.6

P T

.2

D

R= 1,900.00’

T= 270.57’

L= 537.52’

Existing ground

Line to be constructed

2220 2220

30+00 35+00 40+00 45+00 50+00 55+00 60+00

N

P ip e C u lv e r t

P ip e C u lv e r t

C le a n C u lv e r t I n P la c e

R

T

A p p r o a c h P ip e C u lv e r t

L

T

C le a n C u lv e r t I n P la c e

R

T

10A

A 10

A 10

A 10

A

A 10

A 10

A

CP

13602

CUYD

EXC.

D.4

MT

PHILLIPS 201(1)

A

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D B .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b

BM

R21

NO. 9519

NO. 9520

NO. 9521

NO. 95 17

NO. 95 18

GUY WIRE

GUY WIRE

ELEV 2271.92

ELEV 2271.5216" CONCRETE

1001-3662,6001-8552,15001-16794

ON OLD COUNTY ROAD

S R/W FOLLOWS NORTH FENCE

FAP 142-A

FAP 142-A

P C

.2

P T

.2

BH ST-4

R= 2,050.00’ T= 253.24’ L= 503.93’

0 6

5 7 0 7

5 8

P C

.2

P T

.2

MT D.5

Line to be constructed

Existing ground

PHILLIPS 201(1)

2220 2220

60+00 65+00 70+00 75+00 80+00 85+00 90+00

N

A p p r o a c h P ip e C u lv e r t

L

T

A

CUYD

EXC.

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D C .D

G

B

W A

C K

E R

V O

E R

M A

S

C h e c k e d b y

D e s ig n e d b

NO. 9521

NO. 9522

NO. 9523

NO. 9524

NO. 9525

NO. 9526

NO. 9527

NO. 9528

NO. 9529

NO. 9530

NO. 9531

NO. 9532

GUY WIRE

GUY WIRE

W A R N I

U R I

I L I T Y

FIBEROPTIC

W A R N I

R I

I L I T Y

FIBEROPTIC

W A R N I

R I

I L I T Y

FIBEROPTIC

W A R N I

R I

I L I T Y

FIBEROPTIC

E L

E V

ELEV 2248.29 12" CMP

ELEV 2245.60

ELEV 2245.53

C

O N

C R

E T

E

I N

L E

T N

O T F

O U

N D

30" CMP

ELEV 2249.37

INLET APPROX

BH ST-5

MT D.6

Line to be constructed

Existing ground

PHILLIPS 201(1)

D o N o t

D is tu r b

E x is ti n g D

B L x

R C

B

A p p r o a c h P ip e C u lv e r t

R

T

2210 2210

120+00115+00110+00105+00100+0095+0090+00

N

A 18

10A

A 10

10A

CUYD

EXC.

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D D .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b

NO. 9532

NO. 9533

9534 NO. 9535

NO. 9536

NO. 9537

NO. 9538

NO. 9539

NO. 9540

NO. 9541

NO. 9542 NO. 9543

NO. M3

GUY WIRE

T

2 155 2501

UP

W A R N I

R I

I L I T Y

PHONE

W A R N I

R I

I L I T Y

PHONE

ELEV 2248.80

ELEV 2248.57

E L

E V

E L

E V

C

O N

C R

E T

E

#2565

24" CMP

W A R N I

R I

I L I T Y

FIBER OPTIC

W A R N I

R I

I L I T Y

FIBER OPTIC FAP 142-A

BH ST-6

MT D.7

Line to be constructed

Existing ground

N PHILLIPS 201(1)

P ip e C u lv e r t

2210 2210

150+00145+00140+00135+00130+00125+00120+00

A 10

A 10

CUYD

EXC.

a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D E .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b

POWER POLE

NO. 9543

NO. 9544

NO. 9545

NO. 9546

NO. 9547

NO. 9548

NO. 9549

NO. 9550

NO. 9551 NO. 9552

NO. 9552

NO. 9553 NO. 9554GUY WIRE

W A R N I

R I

I L I T Y

FIBER

18"

CMP

WEIGHT LIMIT

WEIGHT LIMIT

" C

MP

18" CMP

INLET A

PPROX B

URIE

D

FAP 142-A

,2

.2

5+0.5600%

100’ VC

K = 99

,2

.3

+1.569 2%

+0.5053%

,2

.7

,2

.2

,2

.5

-0.3487%

100’ VC

K = 118

SSD = 1324’

,2

.9

100’ VC

K = 93

SSD = 1059’

BH ST-7

BH ST-12

BH ST-13

BH ST-8

MT D.8

Line to be constructed

Profile grade

Existing ground

N PHILLIPS 201(1)

22102210

.5

.0

A 10

A x

A x

A x

GR LT

GR RT

STT ST T

T ST ST T

See sheet G.1 - G.14 Construct new bridge.

203.04A and 203.04B for removal requirements.

Remove existing bridge. See Subsections

176+52.25 Bridge.

See sheet G.1 - G.14 Construct new bridge.

203.04A and 203.04B for removal requirements.

Remove existing bridge. See Subsections

176+52.25 Bridge.

150+00 155+00 160+00 165+00 170+00 175+00 180+00

CUYD

EXC.

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D F .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b

O . 9

N O . 9

N O . 9

N O . 9

N O . 5

E

A N C H

O R

PO

LE

G U

Y W

IR

E

G U

Y W

IR

E

G U

Y W

IR

E

G U

Y W

IR

E

W A

R N I

R I

I

L I

T Y

FIB

E R

Y IN

TE

R S E C

TIO

N

STOP R

O

A D N

A R R O

W S

B O

W D

O

IN

N

W R M

ILE

S

D A N

G E R O

U S

IN

TE

R S E C

TIO

N

E L E V

.2

" C

M

P IN

LE

T, O

U

TLE

T N /F

C S P

C S P

C S P

C S P

(N e n d b u rie d b u rie d p ip e e n d

LA

T

S

IM

A N

TO

N

S U B

D

F A P

A

F A P

A

LS

B

E C K

M A N

YE

LLO

W

F A P

A

BOWDOIN ROAD (60’)

,2

.1

-0.3487%

D

R= 1,200.00’

T= 478.36’

L= 910.39’

P C

.2

P T

.6

H

S

-10

S

-9

S T -11

P C

.2

P T

.6

MT D.9

Line to be constructed

Profile grade

Existing ground

No Scale

CONNECTION DETAIL

section

See typical surfacing asphalt

Existing joint @ 15° skew

Sawcut for vertical

S T -11

0.5% max.

PHILLIPS 201(1)

2220 2220

N

R e m o v e

E x is ti n g

P ip e C u lv e r t

R

T

D o N o t

D is tu r b

E x is ti n g D

B L x

R C

B

180+00 185+00 190+00 195+00 200+00 205+00 210+00

D o N o t

D is tu r b

E x is ti n g

C

S P

R

T method 1

Roadway obliteration, A 10

A 10

A 10

A 10

B

See sheet E.2

Bowdoin Road

Approach 500+00

Mainline 190+86.74 =

72.03 RT

191+40.46

54.28 RT

191+47.61

451 SQFT = 0.010 acres

Malta, MT 59538

P.O. Box 945

Blunt Ranches Inc.

CP

13603

13604

CP

CUYD

EXC.

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D G .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b y

El. = 2 257.13

E=2 390 646.66

N= 1 506 737.82

206+00.00

MT PHILLIPS 201(1)

BEGIN RESURFACING

END REHABILITATION

210+00 TO 270+00

OLD HIGHWAY 2

Line to be constructed

Line to be constructed

N N

D.10

STATE PROJECT

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D H .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b y

N

W R H

E A

D Q

U A

R T E R S

270+00 TO 314+36.00

OLD HIGHWAY 2

314+36.00

OLD HIGHWAY 2 AND BRIDGE RESTORATION

MT PHILLIPS 201(1)

BEGIN RESURFACING ENTRANCE ROAD

END RESURFACING OLD HIGHWY 2

N

N

CP

26601

D.11

STATE PROJECT

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D I .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b y

AND DISPLAY POND PATH

HEADQUARTERS ACCESS ROAD

DISPLAY POND

NWR HEADQUARTERS

Display pond path

Headquarters parking area

Access Road

NWR Headquarters

Wood bollards

N

BRIDGE RESTORATION

OLD HIGHWAY 2 AND

END PROJECT MT PHILLIPS 201(1)

314+36.00

OLD HIGHWAY 2 AND BRIDGE RESTORATION

MT PHILLIPS 201(1)

BEGIN RESURFACING ENTRANCE ROAD

END RESURFACING OLD HIGHWAY 2

CP

26602

D.12

STATE PROJECT

M a y

I n t_ ft

F d r iv e H ig h w a y s F

H W

A

O ld

H ig h w a y D e s ig n P la n a n d P r o fi le m t-

A

D J .D

G N

B

W A

C K

E R

C

V O

E R

M A

N S

C h e c k e d b y

D e s ig n e d b y

Appendix 2

Boring ST-1, looking up station. Boring ST-1, Looking down station.

Boring ST-2, looking up station. Boring ST-2, looking down station.

Boring ST-3, looking up station. Boring ST-3, looking down station.

Boring ST-4, looking up station. Boring ST-4, looking down station.

Boring ST-5, looking up station. Boring ST-5, looking down station.

Boring ST-6, looking up station. Boring ST-6, looking down station.

Boring ST-7, looking up station. Boring ST-7, looking down station.

Boring ST-8, looking up station. Boring ST-8, looking down station.

Boring ST-9, looking up station. Boring ST-9, looking down station.

Boring ST-10, looking up station. Boring ST-10, looking down station.

Boring ST-10, looking up Bowdoin Road. Boring ST-11, looking up station.

Boring ST-11, looking down station.

12/06/12

Order of Descriptors

Criteria For Descriptors

- Angularity of coarse grained soils

Consistency of Fine Grained Soils

Very Stiff 16 - 30

Apparent Density of Coarse Grained Soils

Loose 4 - 10

Dense 31 - 50

Dry -Absence of moisture, dusty, dry to the touch.

Moist -Damp, but no visible water.

Angularity of Coarse-Grained Particles

Moisture Condition

- Other relevant notes

Medium Dense 11 - 30 plane sides with unpolished surfaces.

but have rounded edges.

well-rounded corners and edges.

Rounded -Particles have smoothly curved sides and no edges.

Definition of Particle Size Ranges

Boulder

Cobble

Gravel

Sand

Silt

Clay between silt and clay.

> 12 in (300 mm)

3 in (75 mm) - 12 in (300 mm)

No. 4 Sieve (4.75 mm) to 3 in (75 mm)

No. 200 (0.075 mm) to No. 4 Sieves (4.75 mm)

< No. 200 Sieve (0.075 mm)*

< No. 200 Sieve (0.075 mm)* grained soils only)

Consistency N-Value (uncorrected)

Soil Component Size Range

Subrounded-Particles have nearly plane sides, but have

Subangular -Particles are similar to angular description, Angular -Particles have sharp edges and relative

Very Loose < 4

Very Dense > 50

Very Soft < 2

Soft 2 - 4

Medium Stiff 5 - 8

Stiff 9 - 15

Hard > 30

Relative Density N-Value (uncorrected)

- Group Name

- Consistency or Relative Density

- Moisture Condition

- Color

- Particle size descriptor(s) (coarse

Wet -Visible free water.

Soil Classifications are Based on the…