GEOTECHNICAL INVESTIGATION

Transcription

1 GEOTECHNICAL INVESTIGATION I-80 WILDLIFE SILVER ZONE PASS ELKO COUNTY, NEVADA EA #73438 JULY 2011 MATERIALS DIVISION

2

3 Table of Contents 1.0 INTRODUCTION PROJECT DESCRIPTION SITE DESCRIPTION FIELD EXPLORATION Drilling Rock Coring Procedure ReMi Survey LABORATORY TESTING DISCUSSION Site Geology and Subsurface Soil/Bedrock Conditions Soil Moisture and Groundwater Conditions Electrochemical Test Results Geologic Hazards Faulting and Site Seismicity Liquefaction RECOMMENDATIONS Earthwork Foundations Mechanically Stabilized Earth (MSE) Walls Settlement Seismic Design Parameters REFERENCES...

4 Table of Contents (continued) APPENDIX A Boring Location Map APPENDIX B Key to Boring Logs Boring Logs Rock Core Photographs APPENDIX C Summary of Laboratory Test Data Laboratory Test Reports APPENDIX D ReMi Results

5 1.0 INTRODUCTION Presented herein is the Nevada Department of Transportation s (NDOT s) Geotechnical Investigation for the proposed wildlife overcrossing on Interstate 80 (I-80) near Silver Zone Pass west of Wendover, Nevada in Elko County. The project location is presented below in Figure 1 Project Location. The objective of this investigation was to determine general soil and ground water conditions at the project site to provide recommendations for design and construction of the project as related to these conditions and included the following: Subsurface field exploration and soil sampling; Refraction Microtremor (ReMi) surveys; Laboratory testing; Reviews of published geologic maps and preliminary design information; Geotechnical engineering analysis. Results of our reviews, field exploration and testing programs form the basis for the conclusions and recommendations presented in this report. N NTS SILVER ZONE PASS APPROXIMATE PROJECT LOCATION FIGURE 1 1 Project Location 26 MILES TO WENDOVER PROJECT DESCRIPTION Based on preliminary plans, the overcrossing structure will comprise two corrugated steel horizontal elliptical arches placed over the eastbound and westbound travel lanes of I-80. The structures will be approximately 200 feet in length. It should be noted that other types of prefabricated structures may also be considered.

6 In addition, Mechanically Stabilized Earth Walls (MSEW) will be constructed to reduce the footprint of the backfill material placed over the structures. 3.0 SITE DESCRIPTION The project is located on I-80 approximately one mile southeast of Silver Zone Pass in Section 17, Township 35 North, Range 68 East. I-80 consists of five asphalt-paved travel lanes with two eastbound travel lanes and three westbound travel lanes that include a truck passing lane. The wildlife overcrossing is to be located within a cut section of I-80 as presented in Figure 2 presented below. The general elevations of the roadway at proposed wildlife crossing is 5,680 feet at N NTS the southeast end of the structure and 5,688 feet at the northwest end with a slope PROPOSED WILDLIFE OVERCROSSING gradient of about 4 percent to the southeast. Vegetation in the project area generally consists of sage and various other shrubs with minor scattered grasses. Scattered pinion pine and juniper trees were observed FIGURE 2 Aerial Photograph of Site 2 in the hills southwest of the project area. 4.0 FIELD EXPLORATION 4.1 Drilling Field exploration consisted of drilling 12 borings at two proposed locations for the wildlife overcrossing on September 14 th and 15 th, 20 and May th through 12 th, Borings were drilled within the median and on the outside shoulders of both the east and westbound travel lanes of I-80. Boring locations are presented on the attached Boring Location Map in Appendix A of this report. The first six (6) borings (SZP1 through SZP-6) were drilled between Stations and Following further assessment by NDOT, the proposed overcrossing location was shifted approximately 0 feet to the east. Six (6) additional borings (SZP-7 through SZP-12) were drilled at 2

7 this location between Stations to Borings SZP-1, SZP-6, SZP-9 and SZP- were drilled within the asphalt-paved outside shoulder of the westbound lane. Borings SZP-4, SZP-5, SZP-7 and SZP-8 were drilled within the median. Borings SZP-2, SZP-3, SZP-11 and SZP-12 were drilled within the outside shoulder of the eastbound lane. Borings were drilled to refusal on bedrock at depths ranging from 3 to 26 feet. The locations of Borings SZP-1 through SZP-6 were obtained by the District III survey section. The remaining boring locations were obtained using a handheld resource grade Global Positioning System (GPS). Elevations of the borings were obtained from topographical data compiled by NDOT. The locations and elevations of the borings should be considered accurate only to the degree implied by the method used. The borings were drilled using a Diedrich D120 drill rig (Drill Rig Unit #82) equipped with an automatic hammer utilizing Hollow Stem Continuous Flight Auger (HSA) and Mud Rotary/Rock Coring methods. NDOT engineers logged the subsurface conditions encountered during the field investigation. Soils were classified according to the Unified Soil Classification System (USCS) as described in American Society of Testing and Materials (ASTM) D A brief key to the USCS is included in Appendix B on the Key to Boring Logs sheet. The borings were backfilled with drill cuttings upon completion and the pavement surface was patched with cold mix asphalt where necessary. Bulk soil samples were collected from auger cuttings at various depths from Boring SZP-2, SZP-3, SZP-4, SZP-9, SZP-, and SZP-12. Soil samples were also obtained using a Standard Penetration Sampler driven 18 inches (unless otherwise noted) into the bottom of the boring using a 30-inch drop of a 140-pound hammer (Standard Penetration Test ). The number of blows to drive the sampler the final 12 inches of an 18-inch penetration into undisturbed soil provides an N-value (presented as Blow Count on the boring logs). The N-value is an indication of the apparent density/consistency of the in situ soils. It should be noted that the blow counts presented on the boring logs have not been corrected for energy, sampler type, rod length, hammer type, etc. The 3

8 energy transfer from the automatic hammer into the drill rig string was calibrated at 87.5% for Unit #1802 ( Calibration done by Gregg Drilling and Testing, Inc., June 18, 2009). Soil samples were returned to the NDOT Materials and Testing Laboratory and tested as described under the Laboratory Testing section of this report. The maximum particle size recovered using the sampler is approximately 1-3/8 inches. Therefore, the boring logs may not adequately represent the actual quantity or presence of gravels, cobbles or boulders. 4.2 Rock Coring Procedure Rock coring was conducted in Boring SZP-11 to assess the general quality of the bedrock. Core drilling was conducted in accordance to ASTM D 2113 using rotary drilling methods with potable water as a drilling fluid. The rock coring was accomplished with wireline coring system with a diamond-impregnated coring bit. Christensen Double-Tube core barrels were used to recover rock cores. N-sized cores were collected at a depth ranging from 6 feet to feet. The core recovery and Rock Quality Designation (RQD) are recorded on the boring logs. Photographs of the cores are presented in Appendix B. 4.3 ReMi Survey ReMi geophysical surveys were conducted along the south shoulder of the eastbound travel lane (RSZP-1) and along the approximate centerline of the median (RSZP-2) on May 12 th, ReMi data was obtained at each location using cables with 12 geophones spaced 20 feet apart. Broad ambient noise was used as a surface wave (S-wave) energy source. The locations of the ReMi survey lines are shown on the Boring Location Map in Appendix A. Data collected from the field was sent to Optim Software and Data Solutions for analysis. Results of the ReMi surveys are presented in Appendix D and are discussed in Section 6.4 of this report. 4

9 5.0 LABORATORY TESTING Laboratory data is presented in Appendix C of this report and include a summary of test results and graphical reports. Laboratory testing program for selected samples consisted of: Natural Moisture Contents (Nev. T-4) Particle Size Gradations (Nev. T-206) Atterberg Limits (Nev. T-2, T-211 and T-212) Electrochemical analyses (AASHTO T-288, T-289, T-290 and T-291) Resistance Value (R-Value, Nev. T-115) 6.0 DISCUSSION 6.1 Site Geology and Subsurface Soil/Bedrock Conditions Silver Zone Pass lies within the Toano Range and the geology comprises Jurassic-aged granite and Quaternary-aged alluvium with silt, sand and gravel deposits. 3 Based on the results of our field exploration and laboratory testing, the project site overlies subsurface soil/bedrock consisting of decomposed granite to competent granite bedrock. Selected soil samples generally classified as silty to clayey sand, poorly to well graded sand with silt and poorly to well graded gravel with silt. In general, the amount of material passing the No. 200 sieve ranged from about 5 to 27 percent. Liquid limits ranged from 18 to 28 and soil plasticity ranged from nonplastic to a Plasticity Index of 9. It should be noted that the degree of weathering and depth of the bedrock varies across the project area. Refusal on bedrock was encountered at depths ranging from 3 to 26 feet below the ground surface. 6.2 Soil Moisture and Groundwater Conditions Subgrade soils were encountered in a dry to moist condition. No groundwater was encountered during the field exploration and is anticipated to lie at a depth well below that which would affect construction. Fluctuations in soil moisture and/or groundwater conditions as noted in this report may occur due to variations in precipitation and other factors. 5

10 6.3 Electrochemical Test Results Chemical analyses were conducted on selected samples from Borings SZP-4 and SZP-12 for assessment of the corrosion potential of the site soils. The samples were tested for ph, resistivity, soluble sulfates, and soluble chlorides. Electrochemical analyses were performed on the subsurface soil samples to determine the concentration of corrosive chloride and sulfate salts. Soil ph values that represent the hydrogen concentration in the soil (referred to as the intensity factor), and soil resistivity which is an indirect measurement of the soluble salt content in the soil, were also measured. Results of these analyses are provided in Appendix C. 6.4 Geologic Hazards Faulting and Site Seismicity No mapped faults trend through the project area. The nearest fault presented on the referenced geologic map is a northeast-southwest trending fault terminating about 1 mile south of the wildlife crossing. A more recent fault map 4, presented as Figure 3 Quaternary Faults in the Project Area, was reviewed that does not show this fault. This fault map indicates two (2) generally north-south trending Quaternary faults located approximately 3 FIGURE 3 4 Quaternary Faults in the Project Area miles northeast and over 5 miles southeast of the project site along the eastern base of the Toano Range. A latest Quaternary fault is located adjacent to the southeast fault. PROJECT LOCATION N NTS The project areas lies within the Basin and Range physiographic province, a seismically active area that extends from the eastern base of the Sierra Nevada mountain range in western Nevada/California eastward to the Wasatch Front in eastern Utah. In general, most seismic activity within Nevada 6

11 occurs along the western and southwestern portions of the state; however, a 6.0 magnitude earthquake occurred in February 2008 with the epicenter located about five miles north-northeast of Wells, Nevada. 5 The epicenter is approximately 33 miles northwest of the project site Liquefaction Liquefaction is a nearly complete loss of soil shear strength that can occur during an earthquake as cyclic shear stresses generate excessive pore water pressure between the soil grains and the higher the ground acceleration, or the longer the duration of shaking, the more likely liquefaction is to occur. This phenomenon is generally limited to unconsolidated sands (up to 35 percent non-plastic fines) lying below the groundwater table. Due to the presence of shallow bedrock, the potential for liquefaction is negligible. 7.0 RECOMMENDATIONS 7.1 Earthwork All excavation and site preparation shall be performed in accordance with NDOT 2001 Standard Specifications for Road and Bridge Construction. All permanent embankment slopes should be constructed at a maximum 2:1 slope (Horiz:Vert). The contractor shall be responsible for all necessary shoring. All shoring must be in compliance with the Code of Federal Regulations 29 CFR part For excavations less than 20 feet deep, the native decomposed granite should be considered OSHA Type C for temporary excavation purposes with an allowed OSHA maximum allowable slope of 1½H:1V. For stable granite rock, the maximum allowable slope is 90 degrees (vertical). The contractor should monitor the existing paved roadway adjacent to excavations for deflection or damage to the structural section of the roadway. It should be noted that shallow bedrock may likely be encountered during excavation activities. 7

12 7.2 Foundations Shallow spread footings are recommended for the proposed structures. It is our understanding that the width of the footing for the structure over the eastbound lane is restricted to six (6) feet due to the location of the Johnson Springs waterline that runs parallel to the eastbound lane. The transmission will consist of either a 20 DIPS or 21 HDPE pipe encased in ½ -thick steel pipe with a 36 diameter. The embedment depth of the footings will be limited to a maximum depth of four (4) feet to reduce pressure on the waterline from the overcrossing structure. Provided that foundation grade soils are prepared in accordance with NDOT standards and specifications, spread footings for retaining walls placed within embankment fill can be designed for a factored bearing capacity of 4,000 pounds per square foot (psf). Spread footings for the arch structures and retaining walls placed on native soil and/or bedrock can be designed for a factored bearing resistance of,000 psf (strength limit state). This bearing pressure may be increased by onethird for total loading conditions, including wind and seismic forces. The weight of the foundation which extends below grade and backfill may be neglected when computing dead loads. The frost depth in the project area is three feet. Lateral loads, such as wind or seismic, may be resisted by passive soil pressure and friction on the bottom of the footing. A friction factor of 0.40 may be utilized for sliding resistance at the base of the spread footing. Design value for passive equivalent fluid pressures is 300 psf per foot of depth. Both the passive pressure and sliding resistance can be assumed to act concurrently. In designing for passive pressure, the soil above the footing should not be included unless confined by a concrete slab, or pavement. Design values are based on spread footings bearing on either native granular soils, or structural fill and backfilled with structural fill. The base of all excavations should be dry and free of loose materials at the time of concrete placement. Loose, soft, wet, frozen or disturbed soils encountered at foundation subgrade should be removed to expose suitable soils and the resulting excavation shall be backfilled with compacted granular fill. 8

13 7.3 Mechanically Stabilized Earth (MSE) Walls For this project, NDOT has eliminated the requirement to use only approved MSE walls from the Qualified Products List (QPL). The requirement to use inextensible reinforcement has also been eliminated as well as the requirement of the 30 square-foot maximum MSE panel size. The in-place soil parameters for MSE walls are as follows: Cohesion, c = 0 psf Soil Friction Angle (φ) = 35 Soil Unit Weight (γ d ) = 125 pounds per cubic foot (pcf) 7.4 Settlement Total settlement of an individual foundation will vary depending on the plan dimensions of the foundation and the actual load supported. Based on anticipated foundation dimensions and loads, we estimate that total post-construction settlement of footings designed and constructed in accordance with the preceding recommendations will be less than 1 inch (service limit state). Differential settlement between similarly loaded, adjacent footings is expected to be less than ¼-inch, provided footings are founded on similar materials (e.g., all on engineered fill, native soil, or rock). Differential settlement between adjacent footings founded on dissimilar materials (e.g., one footing on soil and one footing on rock) may approach the maximum, anticipated total settlement. Settlement of all foundations is expected to occur rapidly and should be essentially complete shortly after initial application of the loads due to the very dense granular soils and shallow bedrock present at the site. 7.5 Seismic Design Parameters An Optim Software and Data Solutions representative performed interpretations of the data collected at each ReMi survey line using the most current SeisOpt ReMi software. The average shear wave velocity is presented by the 1-dimensional shear wave velocity profiles located in Appendix C. These plots depict variations in shear wave velocity profiles to a depth of feet. The average shear wave velocity for the upper feet of the soil profile (V s ) is used to determine the Site Class Definition as defined by Table of AASHTO LRFD Bridge Design Specifications. The 9

14 average shear wave velocity for RSZP-1 is 4,445 feet per second (ft/s) and 4,715 ft/s for RSZP-2. These values, in conjunction with our field exploration, indicate the project area is Site Class B (Rock). Based on the NDOT Bridge Manual for Elko County, the Peak Ground Acceleration is 0.15g with a Short-Period Acceleration Coefficient (S s ) of 0.40 and a Long-Period Spectral Acceleration Coefficient (S d ) of REFERENCES 1. Silver Zone Pass 7.5 Minute Quadrangle, United States Geologic Survey, 1971, photorevised ArcGIS Explorer, ESRI, Bing Base Maps (NASA, NGA, USGS), aerial. 3. Geology of Elko County, Nevada Bureau of Mines and Geology, Bulletin 1, Quaternary Faults in Nevada, Nevada Bureau of Mines and Geology, Craig M. de Polo, Quake Shakes Wells, Nevada (Updated), Las Vegas Sun, February 21, Standard Specifications for Road and Bridge Construction, State of Nevada Department of Transportation, AASHTO LRFD Bridge Design Specifications, 5 th edition, 20.

15 APPENDIX A BORING LOCATION MAP

16

17 APPENDIX B KEY TO BORING LOGS BORING LOGS ROCK CORE PHOTOGRAPHS

18 KEY TO EXPLORATION LOGS PARTICLE SIZE LIMITS CLAY SILT SAND GRAVEL COBBLES BOULDERS FINE MEDIUM COARSE FINE COARSE.002 mm #200 #40 # #4 ¾ inch 3 inch 12 inch USCS GROUP GW GP GC SW SP SM SC ML CL OL MH CH OH PT TYPICAL SOIL DESCRIPTION Well graded gravels, gravel-sand mixtures, little or no fines Poorly graded gravels, gravel-sand mixtures, little or no fines Clayey gravels, poorly graded gravel-sand-clay mixtures Well graded sands, gravelly sands, little or no fines Poorly graded sands, gravelly sands, little or no fines Silty sands, poorly graded sand-silt mixtures Clayey sands, poorly graded sand-clay mixtures Inorganic silts and very fine sands, rock flour, silty or clayey fine sands with slight plasticity Inorganic clays of low to medium plasticity, gravelly clays, sandy clays, silty clays, lean clays Organic silts and organic silt-clays of low plasticity Inorganic silts, micaceous or diatomaceous fine sandy or silty soils, elastic silts Inorganic clays of high plasticity, fat clays Organic clays of medium to high plasticity Peat and other highly organic soils MOISTURE CONDITION CRITERIA SOIL CEMENTATION CRITERIA Description Criteria Description Criteria Dry Absence of moisture, dusty, Weak Crumbles or breaks with handling or little dry to touch. finger pressure. Moist Damp, no visible free water. Moderate Crumbles or breaks with considerable Wet Visible free water, usually below finger pressure. groundwater table. Strong Won t break or crumble w/finger pressure Groundwater Elevation Symbols TEST ABBREVIATIONS CD CONSOLIDATED DRAINED CH CHEMICAL (CORROSIVENESS) CM COMPACTION CU CONSOLIDATED UNDRAINED D DISPERSIVE SOILS DS DIRECT SHEAR E EXPANSIVE SOIL G SPECIFIC GRAVITY H HYDROMETER HC HYDRO-COLLAPSE K PERMEABILITY OC ORGANIC CONTENT C CONSOLIDATION PI PLASTICITY INDEX RQD ROCK QUALITY DESIGNATION RV R-VALUE S SIEVE ANALYSIS SL SHRINKAGE LIMIT U UNCONFINED COMPRESSION UU UNCONSOLIDATED UNDRAINED UW UNIT WEIGHT W MOISTURE CONTENT SOIL COLOR DESIGNATIONS ARE FROM THE MUNSELL SOIL/ROCK COLOR CHARTS. EXAMPLE: Revised August 20 STANDARD PENETRATION CLASSIFICATION * GRANULAR SOIL CLAYEY SOIL BLOWS/FT DENSITY BLOWS/FT CONSISTENCY OVER VERY LOOSE LOOSE MEDIUM DENSE DENSE VERY DENSE *Standard Penetration Test (N) 140 lb hammer 30 inch free fall on 2 inch O.D. x 1.4 inch I.D. sampler. (7.5 YR 5/3) BROWN 0-1 VERY SOFT 2-4 SOFT 5-8 MEDIUM STIFF 9-15 STIFF VERY STIFF HARD OVER 60 VERY HARD Field Blow counts on California Modified Sampler (NCMS) can be converted to N field by: (NCMS field )(0.62) = N field Blow counts from Automatic Hammer can be converted to Standard N60 by: Rig #1627: (N field)(1.2) =N60 Rig #82: (N field)(1.45) =N60 SAMPLER NOTATION CMS CALIF. MODIFIED SAMPLER CPT CONE PENETRATION TEST CS PB RC CONTINUOUS SAMPLER PITCHER BARREL ROCK CORE SH SHELBY TUBE STANDARD PENETRATION TEST TP TEST PIT 1- I.D.= inch 2- I.D.=3.228 inch with tube; 3. inch w/o tube 3- NXB I.D.= inch 4- I.D.= inch

19 EXPLORATION LOG START DATE 9/14/ END DATE 9/14/ JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-1 E.A. # GROUNDWATER LEVEL 5705' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ WB RT 40' MLB Drill Rig #82 E.D. White HSA Yes DATE SHEET 1 OF 1 9/14/ ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE A BLOW COUNT 6 inch Increments Last 1 foot 45 Percent Recov'd 87 LAB TESTS PI, S, W USCS Group MATERIAL DESCRIPTION WELL TO POORLY GRADED SAND WITH CLAY AND GRAVEL dry to moist, tan with approximately 45% gravel, 47% sand, 8% low plastic fines NOTE: Material becomes less weathered at 7 feet. REMARKS B C PI, S, W PI, S, W 7.00 POORLY GRADED SAND WITH SILT AND GRAVEL moist, tan with approximately 32% gravel, 57% sand and 11% low plastic fines D PI, S, W SP SM E REFUSAL AT 14 FEET ON BEDROCK. 20 NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

20 EXPLORATION LOG START DATE 9/14/ END DATE 9/14/ JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-2 E.A. # GROUNDWATER LEVEL 5707' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ EB RT 31' MLB Drill Rig #82 E.D. White HSA Yes DATE SHEET 1 OF 1 9/14/ ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE B BULK BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd A LAB TESTS PI, S, W USCS Group GP GM 3.00 MATERIAL DESCRIPTION POORLY GRADED GRAVEL WITH SILT AND SAND dry, tan with approximately 57% angular gravel and cobbles, 36% sand, 7% low plastic fines REFUSAL AT 3 FEET ON BEDROCK. REMARKS NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

21 EXPLORATION LOG START DATE 9/14/ END DATE 9/14/ JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-3 E.A. # GROUNDWATER LEVEL ' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ EB RT 31' MLB Drill Rig #82 E.D. White HSA Yes DATE SHEET 1 OF 1 9/14/ ELEV. (ft) SAMPLE DEPTH (ft) NO. TYPE A BULK BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS PI, S USCS Group SP SM MATERIAL DESCRIPTION SILTY SAND dry to moist, tan, with 9% angular gravel, 76% sand, 15% low plastic fines REMARKS 3.00 POORLY GRADED SAND WITH SILT dry to moist, tan, angular gravel B SP SM 13. REFUSAL AT 13 1/2 FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

22 EXPLORATION LOG START DATE 9/15/ END DATE 9/15/ JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-4 E.A. # GROUNDWATER LEVEL 5705' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ MEDIAN MLB Drill Rig #82 E.D. Whtie HSA Yes DATE SHEET 1 OF 1 9/15/ ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE C A B BULK BLOW COUNT 6 inch Increments Last 1 foot 99 Percent Recov'd 93 LAB TESTS PI, S USCS Group SM 4.00 MATERIAL DESCRIPTION SILTY SAND dry to moist, tan with approximately 12% angular gravel, 72% sand, 16% low plastic fines POORLY GRADED SAND WITH SILT dry to moist, tan with angular gravel REMARKS D SP SM E NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/ REFUSAL AT 26 FEET ON BEDROCK.

23 EXPLORATION LOG START DATE 9/15/ END DATE 9/15/ JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-5 E.A. # GROUNDWATER LEVEL ' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ MEDIAN MLB Drill Rig #82 E.D. Whtie HSA Yes DATE SHEET 1 OF 1 9/15/ ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS USCS Group MATERIAL DESCRIPTION CLAYEY SAND WITH GRAVEL dry to moist, tan with 32% angular gravel, 41% sand, 27% low plastic fines REMARKS A B C PI, S, W PI, S, W SC SP SC POORLY GRADED SAND WITH CLAY moist, tan, angular gravel POORLY GRADED SAND WITH SILT moist, tan, angular gravel SP SM D REFUSAL AT 11 FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

24 EXPLORATION LOG START DATE 9/15/ END DATE 9/15/ JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-6 E.A. # GROUNDWATER LEVEL ' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ WB RT 39' MLB Drill Rig #82 E.D. Whtie HSA Yes DATE SHEET 1 OF 1 9/15/ ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS USCS Group MATERIAL DESCRIPTION POORLY GRADED SAND WITH SILT dry to moist, tan with angular gravel REMARKS A SP SM REFUSAL AT 7 FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

25 EXPLORATION LOG START DATE 5//11 END DATE 5//11 JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-7 E.A. # GROUNDWATER LEVEL 5686' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ MEDIAN MLB Drill Rig #82 O. Altamirano HSA Yes DATE SHEET 1 OF 1 05//11 ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS USCS Group MATERIAL DESCRIPTION POORLY GRADED SAND WITH SILT dry to moist, tan, angular gravel REMARKS A W SP SM REFUSAL AT 4 FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

26 EXPLORATION LOG START DATE 5//11 END DATE 5//11 JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-8 E.A. # GROUNDWATER LEVEL 5679' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ MEDIAN MLB Drill Rig #82 O. Altamirano HSA Yes DATE SHEET 1 OF 1 05//11 ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS USCS Group MATERIAL DESCRIPTION POORLY GRADED SAND WITH SILT dry to moist, tan, angular gravel REMARKS A W SP B W 6. REFUSAL AT 6 1/2 FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

27 EXPLORATION LOG START DATE 5//11 END DATE 5//11 JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-9 E.A. # GROUNDWATER LEVEL ' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ WB RT 35' MLB Drill Rig #82 O. Altamirano HSA Yes DATE SHEET 1 OF 1 05//11 ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS USCS Group MATERIAL DESCRIPTION SILTY SAND WITH GRAVEL dry to moist, tan with 26% angular gravel, 61% sand, 13% low plastic fines REMARKS A 90 W SM B BULK PI, S C E D BULK PI, S, W PI, S W SW SM WELL GRADED SAND WITH SILT AND GRAVEL moist, tan with approximately 27% angular gravel, 65% sand, 8% low nonplastic fines HIGHLY TO MODERATELY WEATHERED GRANITE light tan, highly weathered material is similar to a POORLY GRADED SAND WITH SILT with approximately 11% gravel, 78% sand and 11% low plastic fines SP F 18. REFUSAL AT 18 1/2 FEET ON BEDROCK. 20 NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

28 EXPLORATION LOG START DATE 5//11 END DATE 5//11 JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP- E.A. # GROUNDWATER LEVEL 5689' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ WB RT 33' MLB Drill Rig #82 O. Altamirano HSA Yes DATE SHEET 1 OF 1 05//11 ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE A BLOW COUNT 6 inch Increments Last 1 foot 42 Percent Recov'd LAB TESTS PI, S, W USCS Group SW SM MATERIAL DESCRIPTION WELL GRADED SAND WITH SILT AND GRAVEL dry to moist, tan with approximately 25% angular gravel, 66% sand and 9% nonplastic fines REMARKS B BULK PI, S HIGHLY TO MODERATELY WEATHERED GRANITE light tan, highly weathered material is similar to a WELL GRADED GRAVEL WITH SILTY CLAY AND SAND with approximately 75% angular gravel, 20% sand and 5% low plastic fines REFUSAL AT 6 1/2 FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

29 EXPLORATION LOG START DATE 5/11/11 END DATE 5/11/11 JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-11 E.A. # GROUNDWATER LEVEL 5690' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ EB RT 32' MLB Drill Rig #82 O. Altamirano SHEET 1 OF 1 MUD ROTARY/CORING Yes DATE 05/11/11 ELEV. (ft) DEPTH (ft) SAMPLE NO. TYPE BLOW COUNT 6 inch Increments Last 1 foot Percent Recov'd LAB TESTS USCS Group MATERIAL DESCRIPTION POORLY GRADED SAND WITH SILT dry to moist, tan with approximately % gravel, 79% sand and 11% low plastic fines REMARKS A PI, S SP SM B 5. GRANITE BEDROCK CORE RECOVERTY = 92% RQD = 83% C CORE BOTTOM OF CORE AT FEET. 20 NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

30 EXPLORATION LOG START DATE 5/11/11 END DATE 5/12/11 JOB DESCRIPTION I-80 WILDLIFE SILVER ZONE PASS LOCATION ELKO COUNTY, NEVADA BORING SZP-12 E.A. # GROUNDWATER LEVEL 5681' (ft) DATE DEPTH ft ELEV. ft GROUND ELEV. NE 0.0 HAMMER DROP SYSTEM AUTO STATION OFFSET ENGINEER EQUIPMENT OPERATOR DRILLING METHOD BACKFILLED ~ EB RT 22' MLB Drill Rig #82 O. Altamirano SHEET 1 OF 1 MUD ROTARY/CORING Yes DATE 05/12/11 ELEV. (ft) SAMPLE DEPTH (ft) NO. TYPE C A BULK BLOW COUNT 6 inch Increments Last 1 foot 90 Percent Recov'd LAB TESTS PI, S PI, S, W USCS Group MATERIAL DESCRIPTION POORLY GRADED SAND WITH SILT TO SILTY SAND dry to moist, tan with approximately 1 to 4% gravel, 76% to 88% sand and % to 19% nonplastic fines REMARKS B D BULK PI, S E.08 REFUSAL AT APPROXIMATELY FEET ON BEDROCK NV_DOT SILVERZONE-OLD.GPJ NV_DOT.GDT 7/19/11 25

31 ROCK CORE PHOTOGRAPHS EA#: I-80 WILDLIFE SILVERZONE PASS

32 APPENDIX C SUMMARY OF LABORATORY TEST DATA LABORATORY TEST REPORTS

33 Boring: SZP-1 Drill Date: 9/14/20 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A* B* SW-SC C SP-SM NP D SP-SM E R Boring: SZP-2 Drill Date: 9/14/20 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A R B BULK GP-GM Boring: SZP-3 Drill Date: 9/14/20 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A BULK SM B R COMMENTS COMMENTS COMMENTS Boring: SZP-4 Drill Date: 9/14/20 DRY SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT COMMENTS (ft) (pcf) A R B R C B SM D E R * - Samples combined for laboratory testing Field Exploration Abbreviations B = Bulk Sample R = Blow Count Refusal = Standard Penetration Sample 1.38" ID SUMMARY OF LABORATORY TEST RESULTS SZP-1 through SZP-4 I-80 WILDLIFE CROSSING AT SILVERZONE PASS

34 Boring: SZP-5 Drill Date: 9/14/20 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A* R SC B* R COMMENTS C R D.0-.4 R Boring: SZP-7 Drill Date: 9/14/20 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A R 1.4 COMMENTS Boring: SZP-8 Drill Date: 9/14/20 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A R 4.1 COMMENTS B R 1.3 Field Exploration Abbreviations * - Samples combined for laboratory testing B = Bulk Sample R = Blow Count Refusal = Standard Penetration Sample 1.38" ID SUMMARY OF LABORATORY TEST RESULTS SZP-5 through SZP-8 I-80 WILDLIFE CROSSING AT SILVERZONE PASS

35 Boring: SZP-9 Drill Date: 5//2011 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A R 1.1 B B SM C SW-SM NP D R 3.2 E B SP-SM Boring: SZP- Drill Date: 5//2011 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A SW-SM NP B B GW-GC Boring: SZP-11 Drill Date: 5//2011 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT (ft) (pcf) A SP-SM B R COMMENTS COMMENTS COMMENTS Boring: SZP-12 Drill Date: 5//2011 DRY SAMPLE SAMPLE SAMPLE USCS W - #200 LL PI UNIT NO. DEPTH TYPE N field GROUP % % % % WEIGHT COMMENTS (ft) (pcf) A SP-SM NP B B SM NP RV = 74 C B SM NP RV = 74 Field Exploration Abbreviations B = Bulk Sample R = Refusal = Standard Penetration Sample 1.38" ID SUMMARY OF LABORATORY TEST RESULTS SZP-9 through SZP-12 I-80 WILDLIFE CROSSING AT SILVERZONE PASS

36 NEVADA DEPARTMENT OF TRANSPORTATION GEOTECHNICAL SECTION E.A. No.: CHEMICAL ANALYSIS PROJECT: I-80 Silver Zone Pass Wildlife Crossing Sample No. Chlorides Sulfates ph Resistivity * ppm * ppm ohm - cm AASHTO T 291 A AASHTO T 290 B AASHTO T 289 AASHTO T 288 SZP-4 C SZP-12 B (BULK 1) ,1 SZP-12 C (BULK 2) ,535 * Deviated from AASHTO T 288 by using a small 4 pin soil box. CHEMICAL ANALYSIS TEST RESULTS EA#: I-80 WILDLIFE SILVERZONE PASS

37 Particle Size Distribution Report 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 # #20 #30 #40 #60 # #140 # PERCENT FINER GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay LL PL D 85 D 60 D D 30 D 15 D C c C u NP Material Description USCS AASHTO well-graded sand with siltyclay and gravel SW-SC A-1-a poorly graded sand with silt and gravel SP-SM A-1-a poorly graded sand with silt and gravel SP-SM A-1-b Project No. EA 73438, Client: M. Boutilier Remarks: Project: Silver Zone Pass Wildlife Crossing Source of Sample: SZP-1 Depth: '' Sample Number: A,B Source of Sample: SZP-1 Depth: ' Sample Number: C Source of Sample: SZP-1 Depth: ' Sample Number: D NEVADA DEPARTMENT OF TRANSPORTATION Figure

38 Particle Size Distribution Report 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 # #20 #30 #40 #60 # #140 # PERCENT FINER GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay LL PL D 85 D 60 D D 30 D 15 D C c C u Material Description USCS AASHTO poorly graded gravel with silt and sand GP-GM A-1-a silty sand SM A-1-b Project No. EA 73438, Client: M. Boutilier Remarks: Project: Silver Zone Pass Wildlife Crossing Source of Sample: SZP-2 Depth: ' Sample Number: B Source of Sample: SZP-3 Depth: ' Sample Number: A NEVADA DEPARTMENT OF TRANSPORTATION Figure

39 Particle Size Distribution Report 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 # #20 #30 #40 #60 # #140 # PERCENT FINER GRAIN SIZE - mm. % +3" % Gravel % Sand % Fines Coarse Fine Coarse Medium Fine Silt Clay LL PL D 85 D 60 D D 30 D 15 D C c C u Material Description USCS AASHTO silty sand SM A-1-b clayey sand with gravel SC A-2-4(0) Project No. EA 73438, Client: M. Boutilier Remarks: Project: Silver Zone Pass Wildlife Crossing Source of Sample: SZP-4 Depth: ' Sample Number: C Source of Sample: SZP-5 Depth: ' Sample Number: A,B NEVADA DEPARTMENT OF TRANSPORTATION Figure

40 Particle Size Distribution Report 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 # #20 #30 #40 #60 # #140 # PERCENT FINER GRAIN SIZE - mm. +3" % GRAVEL % SAND % SILT % CLAY USCS AASHTO PL LL SM A-1-b SW-SM A-1-a NP SP-SM A-1-b SIEVE PERCENT FINER SIEVE PERCENT FINER Material Description inches number silty sand with gravel size size 3/4" /2" /8" D 60 D 30 D GRAIN SIZE COEFFICIENTS NEVADA DEPARTMENT OF TRANSPORTATION #4 # #16 #40 # # # C c C u Source of Sample: SZP-9 Depth: ' Sample Number: B Source of Sample: SZP-9 Depth: ' Sample Number: C Source of Sample: SZP-9 Depth: ' Sample Number: E Client: Project: Project No.: M. Boutilier I-80 Wildlife Crossing at Silver Zone Pass EA 73438, FL-4-11 well-graded sand with silt and gravel poorly graded sand with silt and gravel REMARKS: Figure

41 Particle Size Distribution Report 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 # #20 #30 #40 #60 # #140 # PERCENT FINER GRAIN SIZE - mm. +3" % GRAVEL % SAND % SILT % CLAY USCS AASHTO PL LL SW-SM A-1-a NP GW-GC A-1-a SP-SM A-1-b SIEVE PERCENT FINER SIEVE PERCENT FINER Material Description inches number well-graded sand with silt and gravel size size 3/4".0.0 1/2" well-graded gravel with siltyclay and sand 3/8" D 60 D 30 D GRAIN SIZE COEFFICIENTS NEVADA DEPARTMENT OF TRANSPORTATION #4 # #16 #40 # # # C c C u Source of Sample: SZP- Depth: ' Sample Number: A Source of Sample: SZP- Depth: ' Sample Number: B Source of Sample: SZP-11 Depth: ' Sample Number: A Client: Project: Project No.: M. Boutilier I-80 Wildlife Crossing at Silver Zone Pass EA 73438, FL-4-11 poorly graded sand with silt REMARKS: Figure

42 Particle Size Distribution Report 6 in. 3 in. 2 in. 1½ in. 1 in. ¾ in. ½ in. 3/8 in. #4 # #20 #30 #40 #60 # #140 # PERCENT FINER GRAIN SIZE - mm. +3" % GRAVEL % SAND % SILT % CLAY USCS AASHTO PL LL SP-SM A-1-b NP SM A-1-b NP SM A-1-b NP 18 SIEVE PERCENT FINER SIEVE PERCENT FINER Material Description inches number poorly graded sand with silt size size 1/2".0 3/8" silty sand D 60 D 30 D GRAIN SIZE COEFFICIENTS NEVADA DEPARTMENT OF TRANSPORTATION #4 # #16 #40 # # # C c C u Source of Sample: SZP-12 Depth: ' Sample Number: A Source of Sample: SZP-12 Depth: ' Sample Number: B (BULK 1) Source of Sample: SZP-12 Depth: ' Sample Number: C (BULK 2) Client: Project: Project No.: M. Boutilier silty sand I-80 Wildlife Crossing at Silver Zone Pass EA 73438, FL-4-11 REMARKS: Figure

43 APPENDIX D REMI RESULTS

44 RSZP-1: Vs Model Vs' = ft/s Depth, ft Shear-Wave Velocity, ft/s SHEAR WAVE VELOCITY (ReMi) RESULTS RSZP-1 I-80 WILDLIFE CROSSING AT SILVERZONE PASS

45 RSZP-2: Vs Model Vs' = ft/s Depth, ft Shear-Wave Velocity, ft/s SHEAR WAVE VELOCITY (ReMi) RESULTS RSZP-2 I-80 WILDLIFE CROSSING AT SILVERZONE PASS