B08_Att_03_BRCA_318695_-_Engineering_Reports.pdf

AE Project No: 29964.13.00

NPS | Bryce Canyon Rehabilitate Main Water System at East Creek and Yovimpa Point NPS Contract # 140P2021D0001 | PMIS # BRCA 318695 Basis of Design | Draft 100% Construction Documents

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Appendix J Engineering Survey Data Reports (Electronic Copy Only)

Geotechnical Investigation Bryce Canyon National Park, Rehabilitate the Main Water System National Park Service

Contract Number: 140P2021D0001;

Task Order: 140P2024F091

PMIS #318695

Final January 15, 2026

PEOPLE WHO MAKE IT HAPPEN

Deliverable: Geotechnical Investigation Project: Bryce Canyon National Park, Rehabilitate the Main Water System Client: National Park Service Location: Denver, Colorado Contract No: 140P2021D0001 Task Order: 140P2024F091 PMIS No: BRCA 318695

Submittal: Final Date: January 15, 2026

Prepared by: Stanley Consultants-DOWL Joint Venture

Stamp

NPS Contract No: 140P2021D0001 iNPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

TABLE OF CONTENTS

EXECUTIVE SUMMARY ......................................................................................... I

1.0 INTRODUCTION

1.1 Purpose and Scope

1.2 Project Understanding

1.2.1 Existing Site Conditions

1.2.2 Proposed Construction

2.0 REVIEW OF EXISTING DATA

2.1 Existing Geotechnical Investigations

3.0 INVESTIGATION

3.1 Field Investigation

3.2 Laboratory Testing

4.0 SUBSURFACE CONDITIONS

4.1 Site Geology

4.2 Observed Soil Conditions

4.2.1 Roadbase/Fill

4.2.2 Granular Soils

4.2.3 Clayey Soils/Residual Mudstone and Limestone

4.2.4 Weathered Mudstone and Limestone Bedrock

4.3 Groundwater

4.4 Seismicity

4.4.1 Faulting

4.4.2 Design Accelerations

4.4.3 Liquefaction

5.0 ENGINEERING ANALYSIS AND RECOMMENDATIONS

5.1 Foundation

5.2 Lateral Earth Pressures

5.2.1 Seismic Earth Pressure

5.2.2 Coefficient of Friction

5.3 Slabs-on-Grade

5.4 Drainage

5.5 Pavement Design

5.6 Thrust Restraint

5.7 Horizontal Drilling Considerations

5.8 Earthwork

5.8.1 Trench Excavation

5.8.2 Dewatering

iiNPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

5.8.3 Structural Fill

5.8.4 Compaction Requirements

5.8.5 Testing and Observations

5.8.6 Cold Weather Construction

5.8.7 Wet Weather/Soil Construction

5.8.8 Geosynthetics

5.9 Soil Chemistry and Corrosion

6.0 LIMITATIONS

7.0 REFERNCES

FIGURES

Figure 1: Vicinity and Project Location Figure 2: Exploration Locations (G-01) Figure 3: Exploration Locations (G-02) Figure 4: Surficial Geologic Map

TABLES

Table 1: Exploration Summary Table 2: Laboratory Tests Table 3: Documented Faults Table 4: Seismic Design Parameters Table 5: Lateral Earth Pressures Table 6: Thrust Block Support Table 7: Soil Suitability to HDD Table 8: Fill Specifications Table 9: Compaction Specifications Table 10: Soil Chemistry Test Results

APPENDICES

Appendix A - Exploration Logs Appendix B - Photograph Log Appendix C - Laboratory Test Results

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

NPS Contract No: 140P2021D0001

EXECUTIVE SUMMARY

DOWL prepared this geotechnical report for the National Park Service (NPS). In this report, we specifically address the recommendations for BRCA 318695 – Rehabilitate the Main Water System in Bryce Canyon National Park. We identified the following geotechnical considerations:

The basic soil profile on-site consists of four to 16 feet clayey/residual soils overlaying weathered mudstone and limestone bedrock.

The clayey/residual soils range from sandy clay to clayey sand with some granular soils. The mudstone and limestone is highly weathered.

The site appears to be generally suitable for Horizontal Directional Drilling (HDD). Difficulties with HDD may occur in the highly weathered mudstone and limestone.

The soil profile suggests that some areas of trench excavation may require blasting or heavy equipment with a hydraulic hammer/ripper.

The on-site soils are suitable for backfill, except where structural fill is required.

This section is only a summary. Recognize that we do not provide details in this section, read the report in its entirety for a comprehensive understanding of the items contained herein.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

NPS Contract No: 140P2021D0001

1.0 INTRODUCTION

1.1 Purpose and Scope

DOWL completed a geotechnical investigation for the proposed Rehabilitation of the Water Main at the Bryce Canyon National Recreation Area, Utah. The scope of geotechnical services consisted of reviewing existing geotechnical and geological information, a site visit, field observations, subsurface exploration, laboratory testing, engineering analyses, and preparing this Geotechnical Report. The purpose of these services is to provide geotechnical-related recommendations for project planning and design. See Figure 1 on the next page for the project location.

Our geotechnical engineering scope of work for this project included an initial site visit, drilling nine borings to depths ranging from approximately 10 to 27 feet below existing site grades, laboratory testing for soil engineering properties, and engineering analyses to provide foundation and construction recommendations.

1.2 Project Understanding

1.2.1 Existing Site Conditions

The Bryce Canyon National Park (Bryce Canyon) main water system is aging and in need of repair due to the presence of known and potential unknown leaks. The system includes water mains, laterals, and service connections to visitor, employee, and administrative areas. The raw water line transports water from the Park owned wells approximately 500 feet north of the Park boundary on the Dixie National Forest (DNF), managed by the United States Forest Service, and ends at the Park raw water tanks, which are located just north of the Inspiration Point turnoff. Both the raw water and treated portion of the systems need rehabilitation.

1.2.2 Proposed Construction

Planned work at Bryce Canyon generally consists of the rehabilitation or replacement of:

the raw water line, and the system components including water mains, laterals, and service connections.

The National Park Service plans to perform water line improvements through either trenchless or open trench methods. Trenchless methods are generally being used to avoid and protect biological resources.

Open trench methods are planned for areas that will have less impact on biological resources.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

2.0 REVIEW OF EXISTING DATA

2.1 Existing Geotechnical Investigations

DOWL performed a review of the following geotechnical investigation report:

Pavement Design Report, National Park Service, Bryce Canyon Roundabouts, Garfield County, Utah by Shannon and Wilson, Inc. dated December 2021 (Shannon and Wilson, December 2021).

In this report a soil boring, SW-A6-06, was performed near the route of the planned water line replacement (raw water line). For reference, this boring log is included in Appendix A.

3.0 INVESTIGATION

3.1 Field Investigation

DOWL contracted Buckhorn Engineering to perform fieldwork on June 24, 25 and 26, 2024, which consisted of site observations and drilling of nine geotechnical borings throughout the project area. We present the boring locations in Figures 2 and 3 on the next two pages. South Slope Drilling advanced the borings to depths ranging from 10 to 27 feet below the existing ground surface. Drill methods included Hollow-Stem Auger (HSA) and NQ coring methods. Both HAS drilling and NQ coring methods were performed in borings B-1 and B-8. All other borings were completed using HSA drilling methods only.

Field personnel from Buckhorn Engineering recorded handheld locations and elevations at each boring.

Table 1: Exploration Summary

Boring Number

Drill Depth (feet)

Surface Elevation

(feet)*

Northing (feet)*

Easting (feet)* Location

B-1 27 7,784 1,434,215 10,194,856 Near Bryce Canyon wells** B-2 25 7,787 1,434,801 10,194,078 Near Bryce Canyon wells** B-3 25 7,800 1,435,506 10,193,230 Near Bryce Canyon wells** B-4 10 7,949 1,438,319 10,185,682 North of Highway 63 B-5 27 7,917 1,439,945 10,185,688 North of Highway 63 B-6 27 7,940 1,441,399 10,185,706 North of Highway 63 B-7 12 7,982 1,442,758 10,186,584 North of Highway 63 B-8 15 8,007 1,445,996 10,191,761 Southwest of Sunset Point Road B-9 12 7,921 1,445,342 10,195,021 Near Maintenance Yard

*Estimated from Handheld Device **These borings are Located on DNF Property

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

South Slope Drilling drilled the borings under the direction of a Buckhorn Engineering geologist using a CME 75 track-mounted drill rig equipped with a 8-inch O.D. hollow stem auger and an NQ2 coring system.

Buckhorn Engineering conducted the field exploration referencing the following ASTM standards:

ASTM D6151 Standard Practice for Using Hollow-Stem Augers for Geotechnical Exploration and Soil Sampling, ASTM D1586 Standard Penetration Test (SPT) and Split-Barrel Sampling of Soils, ASTM D3550 Standard Practice for Thick Wall Ring-Lined, Split barrel, Drive Sampling of Soils, ASTM D2113 Standard Practice for Rock Core Drilling and Sampling of Rock for Site Investigation

Buckhorn Engineering performed Standard Penetration Test (SPT) sampling using an automatic hammer and recorded the results on the boring logs. The SPT values on the logs have not been corrected for hammer efficiency, sampler type, overburden stress, etc. The resistance, or N-value, can be used to estimate the relative density of granular soils and the relative consistency of cohesive soils. The field N-value or resistance data is provided on the exploration logs.

Buckhorn Engineering used both a California sampler, 2.5-inch outside diameter (O.D.) and a Standard Penetration Test (SPT), 2.0-inch O.D., during the field investigation. Most correlations are based on SPT results and a 140 lb hammer with a 30-inch drop. Therefore, Buckhorn Engineering corrected the blow counts from the California sampler using the method proposed by Lacroix and Horn (1973) to convert a nonstandard penetration resistance, N1, to the Standard Penetration Resistance, NSPT, as follows:

where: NSPT = “field” Standard Penetration Test blow count (uncorrected for other factors such as overburden pressure, groundwater levels, etc.); D1 = nonstandard sampler diameter; W1 = nonstandard hammer weight; and H1 = nonstandard hammer drop height. L1= nonstandard drive length. Because the hammer weight and drop height were nominally standard, the correction for the nonstandard sampler diameter is simplified as follows:

Buckhorn engineering based the soil descriptions shown on the boring logs on field and laboratory testing referencing ASTM Standards D2487 or D2488. The stratigraphic contacts shown on the individual borehole logs represent the approximate boundaries between soil types. The actual transitions may be more gradual or abrupt. The soil and groundwater conditions depicted are only for the specific dates and locations reported and, therefore, may not necessarily represent other locations and times.

The NQ2 rock core system consists of a double tube core barrel with a diamond coring bit that is raised and lowered by a wireline system. Rotary drilling advances the coring. Water is circulated through the drill rod during coring to remove rock cuttings from the boring. The NQ2 core system recovers a 2.0-inch diameter core while being advanced into the bedrock using a 2.97-diameter diamond core bit. As the drillers recovered core samples, Buckhorn Engineering recorded the run length, recovery, and Rock Quality Designation (RQD) along with the rock type and associated geologic formation, the rock core’s field strength, weathering, fracture index, and structural parameters referencing Buckhorn Engineering’s Rock Classification Description presented in Appendix A.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

Exploration logs are included in Appendix A which includes soil and groundwater conditions as well as SPT information. Appendix B presents photographs of the site conditions and of the samples obtained during drilling.

3.2 Laboratory Testing

Samples were transported to Buckhorn Engineering’s laboratory for testing. Representative field samples were selected for laboratory testing after visual examination of the soil and consideration of the design criteria. Buckhorn Engineering performed tests for index and engineering soil properties in Montrose, Colorado. Buckhorn Engineering’s laboratory also completed the corrosion testing of select soil samples. Laboratory testing included:

Table 2: Laboratory Tests Test Purpose

Natural Moisture Content

ASTM D 2216

Provides a measure of natural (in-situ) water content.

Atterberg Limits

ASTM D 4318

Provides an indicator of the plasticity and mineralogy composition of fine-grained soils.

Particle-Size Distribution

ASTM D 421

Provides a measure of grain sizes of the soils for classification and identification of physical characteristics.

Hydrometer Test

ASTM D 7928

Provides grain-size distribution for fine-grained soils (passing the #200 sieve).

Unit Weight of Soil Specimens

ASTM D 7263

Determines the unit weight of the soil sample based on a known dimension and mass of the specimen.

Corrosion Tests pH – AASHTO T289, Electroconductivity, Soluble Sulfates – CDOT CP-L 2103 (Method B), and Chlorides – CDOT CP-L 2104 (Method B)

To determine the potential for corrosive interaction of soils with concrete and metal.

Standard Proctor ASTM D 698-12 (Method A)

Determines the optimal moisture content and maximum dry density of soil for compaction.

We present laboratory test results on the summary table and figures in Appendix C. Laboratory results are also included in the boring logs in Appendix A.

4.0 SUBSURFACE CONDITIONS

4.1 Site Geology

Bryce Canyon National Park is located in the southwest portion of Utah and is bordered by the Dixie National Forest. There are few fingering creeks in the area that consist of Quaternary sediments that traverse Bryce Canyon. Tertiary aged Conglomerate at Boat Mesa and the Clarion Formation (white and pink limestone members) are mapped in the west side of Bryce Canyon. Cretaceous-aged Wahweap Formation and Straight Cliffs Formation (upper and lower parts) are mapped on the east side of Bryce Canyon (Bowers, 1990).

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

The project area is confined to the west portion of Bryce Canyon and extends into the Dixie National Forest and will be the focus of the geology descriptions and map as shown in Figure 4, two pages following. The Quaternary sediments consists of alluvium consisting of a combination of clay, silt, sand, and gravel and may include colluvium deposits. The Conglomerate at Boat Mesa Formation predominantly consists of tan to gray calcareous and conglomeratic sandstone to light gray to white limestone and conglomeratic limestone. The White Limestone Member of the Claron Formation predominantly consists of white to light gray to tan cliff-forming limestone with resistant caprock. The Pink Limestone Member of the Claron Formation predominantly consists of pale-pink to red to pale-orange to tan limestone, argillaceous limestone, and dolomitic limestone with thin interbeds of calcareous mudstone. This formation forms fluted cliffs, columns, hoodoos, spires, and steep cliffs as evidenced by the badlands of Bryce Canyon.

4.2 Observed Soil Conditions

The generalized soil profile encountered at the proposed construction site consists of clayey sand and sandy clay, and residual soils, overlying weathered/formation mudstone and limestone. The clayey/residual soils range in thickness from approximately zero to 16 feet below the existing ground surface. The weathered mudstone and limestone range in thicknesses from approximately 10 to 27 (deepest borings ended at approximately 27 feet) below the existing ground surface with the exception of boring B-8 where mudstone and limestone was encountered at approximately four feet below the existing ground surface. In Appendix A, we present the exploration logs with lithology descriptions as well as other engineering properties. In the following paragraphs, we provide a general description of the soil strata.

4.2.1 Roadbase/Fill

During exploration, roadbase material consisting of sandy gravel was encountered in borings B-1, B-2, and B-8. Encountered roadbase thickness was approximately one to 1½ feet thick. Fill material was encountered in boring B-9 during the exploration. The fill consisted of silty sand.

4.2.2 Granular Soils

Granular soils were encountered and consisted of silty sand and poorly graded gravel. Granular soils were encountered in borings B-3 and B-6. Stratified layers of granular soils were encountered throughout the site. Boring B-4 had a granular layer that was tested at approximately 5 feet below existing ground surface. The granular soils were dense to very dense in consistency.

The granular soils had one dry density test at 125 pcf, a moisture content range of six to eight percent with an average of seven percent, one Atterberg limits liquid limit of 17 and plasticity index of three, and one fines content test at 12 percent.

4.2.3 Clayey Soils/Residual Mudstone and Limestone

Clayey soils were encountered and consisted of sandy clay to clayey sand. The identified residual mudstone and limestone (residual) was predominantly made up of clayey soils that also contained either sands and/or silts. The clayey/residual soils were encountered in all borings. The clayey/residual soils were soft to stiff with some very stiff zones in consistency.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

The clayey/residual soils had a dry density range of 94 to 108 pounds per cubic foot (pcf) with an average of 102 pcf, a moisture content range of three to 22 percent with an average of 12 percent, an Atterberg limits liquid limit range of 21 to 34 with an average of 26 and plasticity index range of five to 17 with an average of 11, and a fines content range of 36 to 94 with an average of 71 percent.

4.2.4 Weathered Mudstone and Limestone Bedrock

Weathered mudstone and limestone bedrock was encountered in all borings except B-7 and B-9. The mudstone to limestone was weak with occasional hard layers with a weakly bedded structure. Colors of the mudstone to limestone ranged from orange to red to pink to light brown and combinations thereof.

The bedrock was predominantly highly weathered and resulted in a Rock Quality Designation (RQD) of zero percent for cores taken in borings B-1 and B-8. The mudstone and limestone bedrock is mapped as the Claron Formation (both the White Limestone Member and the Pink Limestone Member) and is Tertiary in age.

4.3 Groundwater

Groundwater was encountered between eight and 20 feet below existing ground surface during drilling in borings B-1, B-2, and B-3. Groundwater was not encountered in the rest of the borings. Fluctuations of groundwater can occur due to seasonal moisture conditions, irrigation practices, changes in land use, and many other factors. Groundwater conditions may vary from those encountered at the time of the field investigation, depending upon the influence of these factors.

4.4 Seismicity

4.4.1 Faulting

The proposed development is located in an area of Quaternary faulting. Based on the USGS Quaternary Fault Fold Database (USGS, 2018) two (2) Quaternary faults exist in the project vicinity:

Table 3: Documented Faults

Fault Name Distance from ECC

(km)

Recent Earthquake

Published Slip Rate (mm/yr)

Fault Length

(km)

Average Strike

Sevier/Toroweap Fault Zone

12 Late Quaternary Less than 0.2

250 N18°E

Aquarius and Awapa Plateaus

Faults

52 Undifferentiated Quaternary

Less than 0.2

55 N19°E

Available publications do not include documentation that these faults were offset during the Holocene (the last 15,000 years). Based on the distances to Quaternary faults, the potential for fault rupture at the site is low.

4.4.2 Design Accelerations

DOWL utilized site soil and geologic data, our knowledge of local geology, the project location, Minimum Design Loads, and Associated Criteria for Buildings and Other Structures (ASCE, 2021) and the National

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

Earthquake Hazards Reduction Program (NEHRP) to estimate Seismic Site Classification of "C" at the project site. We queried the ASCE 7 Hazard tool website (ASCE, 2021) recommend seismic design reference the seismic parameters provided in Table 4, below based on the soil conditions and project location:

Table 4: Seismic Design Parameters

Period (seconds) Modified Acceleration

Coefficient for Site Class C (g)

0.0 (peak) PGAM = 0.21

0.2 (short) SDS = 0.33

1.0 (long) SD1 = 0.12

4.4.3 Liquefaction

Liquefaction is the partial or total loss of strength of soils that can occur during strong earthquake shaking of significant duration. Liquefaction is a process where high shear deformations result in a progressive build-up of pore water pressure. Because the seismic load occurs rapidly, the soil does not have time to drain, and the effective stress may be reduced to near zero, resulting in a temporary loss of shear strength. Earthquake-induced liquefaction generally occurs only under particular conditions, which include saturation, strong earthquake ground shaking for a long duration, and loose granular soil.

Liquefaction can also occur in silts and fine-grained soils. Typically, liquefaction occurs where the groundwater table is shallow (5 to 10 feet deep) and generally only at depths less than approximately 50 feet.

Loose, saturated soil materials such as sand, silt, and fine gravel may liquefy when exposed to seismic shaking. To be liquefiable, clay or silt (CL or ML) soil must have a plasticity index (PI) of less than 7, or if the soil classifies as a silty clay (CL-ML), the plasticity index must be less than 5 (Idriss, 2006). Based on the laboratory results, the granular on-site soils could be potentially liquefiable. However, the granular soils were observed to be very dense and were above groundwater.

The potential for liquefaction appears to be low in the area due to the lack of groundwater in most areas, the high density of the soil, and the shallow bedrock.

5.0 ENGINEERING ANALYSIS AND RECOMMENDATIONS

5.1 Foundation

Foundation recommendations are not included as no foundation work is planned for the project. If needed, the geotechnical report can be updated to include foundation recommendations.

5.2 Lateral Earth Pressures

Design below-grade walls for buildings, landscape, and retaining walls and any structure retaining soil to resist both lateral earth pressures from the retained soil adjacent to the structure, as well as hydrostatic pressures from retaining water (if undrained, however we do not recommend). Also, account for lateral surcharge loads from equipment, slopes, or vehicles adjacent to the walls in the structural wall design.

We provide recommended lateral earth pressures for below-grade wall design, below.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

Table 5: Lateral Earth Pressures

Lateral Earth Pressure Case Equivalent Fluid Pressure (pcf)

Imported Structural Fill At-rest - no wall movement (pcf) 60 Active - wall moves away from soil mass, (pcf) 35 Passive - wall moves into soil mass, (pcf) 475

On-Site Clayey/Residual Soil At-rest - no wall movement (pcf) 50 Active - wall moves away from soil mass, (pcf) 30 Passive - wall moves into soil mass, (pcf) 300

On-Site Granular Soil At-rest - no wall movement (pcf) 55 Active - wall moves away from soil mass, (pcf) 35 Passive - wall moves into soil mass, (pcf) 390

The above equivalent fluid pressures assume fully drained conditions and no hydrostatic forces acting on the wall and do not include a factor of safety.

Construct below-grade walls, retaining walls, or other retaining structures with adequate drainage and waterproofing systems as specified by the Architect and Structural Engineer to reduce the potential for instability, leakage, or seepage.

The retaining walls move away from or toward the soil to develop active and passive resistance, respectively. For walls that cannot tolerate movement, structurally design walls utilizing at-rest equivalent earth pressures.

We based the above equivalent fluid pressures on the assumption that the surface of the backfill adjacent to the walls slopes down and away from the wall a minimum of 5 percent for 10 feet to provide drainage.

Lateral surcharge pressures due to equipment, slopes, storage loads, etc., are not included in the above lateral earth pressure recommendations. Use the lateral earth pressure coefficient of 0.5, acting over the below-grade wall height, to estimate the lateral surcharge loads from equipment, adjacent foundations, and slopes behind and above walls.

5.2.1 Seismic Earth Pressure

We recommend using the Mononobe-Okabe approach to determine the additional earth pressures due to earthquakes. For the assumed unit weight of the retained earth at this project, 115 pcf, and the design peak horizontal ground acceleration, 0.21g, estimate the equivalent additional fluid (active) earth pressure acting on the wall: 35 pcf. We calculated this value using ½ the peak ground acceleration in the horizontal direction.

5.2.2 Coefficient of Friction

We recommend using a coefficient of friction of 0.45 between cast-in-place concrete and structural fill and 0.40 between cast-in-place concrete and the native clayey/residual soil. The friction value may be combined with the passive pressure to resist horizontal loads.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

5.3 Slabs-on-Grade

Slab-on-grade recommendations are not included as no foundation work is planned for the project. If needed, the geotechnical report can be updated to include foundation recommendations.

5.4 Drainage

Drainage recommendations are not included as no structure work is planned for the project. If needed, the geotechnical report can be updated to include drainage recommendations.

5.5 Pavement Design

Pavement recommendations are not included as no pavement work is planned for the project. If needed, the geotechnical report can be updated to include pavement recommendations.

5.6 Thrust Restraint

It is understood that thrust blocks may be used throughout the project. Pipe thrust can be restrained by bearing against the soil through a thrust block or by friction between the pipe surface and the soil.

Thrust restraint may be required for any one of these conditions:

Bends in the vertical plane, Bends in the horizontal plane, Valves, Reducers, or Tees.

In all cases, the design engineer must determine the direction and magnitude of the maximum expected pipe thrust.

The thrust block bearing against the soil must resist horizontal and vertical components of the thrust forces. Based on soil types observed during the investigation and procedures set forth by the Ductile Iron Pipe Research Association (DIPRA) and Montana Public Works (MPW), we calculated the following bearing capacities based on an assumed depth of 5 feet. DOWL has provided resistance per foot of depth for thrust blocks. Please note that resistance per foot does not include support related to cohesion, and therefore, the allowable bearing value should be utilized as a starting point for any adjustments.

Table 6: Thrust Block Support

Soil Type Allowable Lateral Bearing (psf)

Resistance per Foot of Depth (pcf)

Surficial Clays/Residual 950 40 Gravels 1,025 200

Rock 2,500 400

For the fully available passive earth pressure to develop, a certain amount of movement is required. In well compacted soil, this movement is typically insignificant; however, in less competent soil, the movement may be detrimental to the water main. For this reason, we applied a reduction factor of 0.85 to the above allowable lateral bearing pressures.

We strongly recommend a Factor of Safety of 1.5 be applied during the sizing of thrust blocks. We recommended that thrust blocks be placed against undisturbed earth or have backfill placed against the

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal thrust block compacted to 97 percent of maximum dry density as determined by ASTM D 698. For thrust restraint by pipe friction, refer to the Ductile Iron Pipe Research Association criteria (DIPRA, Seventh Edition, 2016).

5.7 Horizontal Drilling Considerations

Horizontal borings are planned below the biological areas along the raw water line from the wells site on DNF property to the north edge of Highway 63 in Bryce Canyon, near the existing water tanks, north of Sunset Point Road and north of the Bryce Maintenance Yard. All soil borings were considered for this analysis. We have classified the suitability of the soil for directional drilling, referencing ASTM F1962-20 (Standard Guide for Use of Maxi-Horizontal Directional Drilling for Placement of Polyethylene Pipe of Conduit Under Obstacles, Including River Crossings), in Table 10.

Table 7: Soil Suitability to HDD Boring Suitability Soil Description

All borings (including

SW-A6-06)

generally suitable Medium stiff to stiff clay/silt

Borings B-1 thru B-6 and

B-8 difficulties may occur in fractured rock, massive rock is generally suitable

Mudstone to Limestone

5.8 Earthwork

5.8.1 Trench Excavation

Based on the materials encountered in the soil borings, conventional earthmoving equipment should be capable of excavating most of the site soils. There are areas of the project where bedrock is at shallow depths and will most likely be encountered during excavation. This may require additional excavation processes such as blasting or heavy equipment with a hydraulic hammer/ripper.

The following considerations should be recognized as pertinent to excavations:

Subsurface conditions may vary from those shown on logs of exploration holes and The condition of structures adjacent to waterline excavation areas should be documented prior to construction.

Subsurface conditions identified in this report are based on information from a limited number of exploration holes and may vary between holes. Because the soils are primarily native and residual, the material characteristics should be maintained throughout the area. Additionally, past fill areas that the excavation may encounter may create exceptions to the soil conditions identified herein.

Excavations must conform to OSHA Standards for Excavations, 29 CFR Part 1926.652 Appendix B to Subpart P. Based on field observations and laboratory tests, the soil at the site classifies as OSHA Type C;

however, soil classifications may vary along project extents. OSHA requires that Type C soil excavation slope angles not to exceed 1½H:1V (horizontal to vertical). The nature and extent of subsurface variations and groundwater conditions between the boring locations may not become evident until construction. Evaluate soil conditions during construction by the contractor’s responsible person to comply with OSHA requirements. Temporary excavation slopes may be required for utility trenches.

Conduct excavations and shoring in accordance with OSHA standards. Do not allow surcharges within a horizontal distance equal to half the excavation depth. Construction vibrations can cause excavations to

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal slough or cave. Ultimately, the contractor is solely responsible for site safety and excavation configurations.

5.8.2 Dewatering

Depending on the time of year and precipitation, groundwater may be encountered throughout the project alignment. Dewatering and control of groundwater and subsurface water during trench excavations will be critical to the successful completion of this project. Where and when necessary, dewater prior to making final trench excavations to reduce the potential for groundwater flow through trenches. Dewater to lower groundwater a minimum of 1.5 feet below the planned trench excavation depth. Dewatering of clayey/residual soil has the potential to take long periods of time.

5.8.3 Structural Fill

The on-site clayey/residual and granular soils are suitable for use as fill for utility trenches. Fill specifications are included below.

Table 8: Fill Specifications Soil/Fill Product Allowable Use Material Specifications

General Fill

Utility backfill in non-structural areas

Soil classified as GP, GM, GW, GC, SP, SM, SW, SC, CL, or ML according to the USCS.

Site soil must have less than three percent vegetation, organics, and debris.

Soil may not contain particles larger than 6 inches in diameter.

Soil must contain less than 3% (by weight) of organics, vegetation, wood, metal, plastic, or other deleterious substances

Structural Fill

General fill Near roadway/structure (utility backfill)

Soil classified as GP, GM, GW, SP, SM, or SP with at least 30 percent retained on a number 4 sieve and less than 15 percent passing a number 200 sieve.

Soil may not contain particles larger than 2 inches in diameter.

Soil must contain less than 3% (by weight) of organics, vegetation, wood, metal, plastic, or other deleterious substances

Unsatisfactory Soil NONE

Soil classified as MH, OH, CH, OL, or PT may not be used at the project site Any soil type not maintaining moisture contents within 5% of optimum during compaction is unsatisfactory soil that must be moisture conditioned prior to disposal and replacement Any soil containing more than 3% (by weight) of organics, vegetation, wood, metal, plastic, or other deleterious substances

5.8.4 Compaction Requirements

Place fill material in lifts not exceeding eight inches in uncompacted thickness. Moisture condition and compact fill according to the table below.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

Table 9: Compaction Specifications

Application Moisture Content (% of optimum) Minimum Compaction

Utility Trenches (structural areas) ±2 95% ASTM D698

Utility Trenches (non-structural areas)

Compact soils to similar level of structural areas (no compaction testing required)

Site Grading Fill ±2 95% ASTM D698

5.8.5 Testing and Observations

We recommend the following compaction testing frequency:

Trenches - One compaction test every 150 linear feet or 2 per trench, whichever results in the greater number of tests, per each 1-foot lift of backfill.

5.8.6 Cold Weather Construction

Do not place trench backfill on frozen soil or use frozen soil as trench backfill. Remove frozen soil, snow, and/or ice from the backfill soil prior to continuing with construction. Limit winter trench excavation to areas small enough to be backfilled on the same day. Contact DOWL to monitor backfill placed during freezing conditions to reduce the potential for placing frozen material.

5.8.7 Wet Weather/Soil Construction

Ideally, perform earthwork construction when the soil moisture content is less than two percent above optimum.

The site clay and silt are susceptible to pumping or rutting from heavy loads such as rubber-tired equipment or vehicles any time of the year.

5.8.8 Geosynthetics

Geosynthetic fabrics are applicable when constructing on soft or wet soil at the base of trench excavations. Where required, apply geosynthetics directly on trench bottom, taut, without wrinkles, and over-lapped at least 12 inches. Consult DOWL to review geosynthetic applications or other pipe subgrade improvement alternatives. Geogrid is required to help support any area that exhibits unusually high groundwater, soft pumping, or rutting conditions.

5.9 Soil Chemistry and Corrosion

Based on the results shown in the table below, concrete in contact with the on-site soil classifies as exposure class S0 according to ACI 318 table 19.3.1.1 (ACI, 2014). This sulfate classification has no concrete type restrictions.

According to Corrosion/Degradation of Soil Reinforcement for Mechanically Stabilized Earth Walls (FWHA, 2009) the soil at the site is “moderately corrosive to corrosive” to steel. Based on that publication and the test results below, we estimate a corrosion rate of 1.1 ounces per square foot per year for carbon steel and 1.1 ounces per square foot per year for galvanized steel.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

Table 10: Soil Chemistry Test Results

Sample Location Soluble Sulfate (ppm)

Chlorides (ppm)

Resistivity* (Ohm-cm) pH

Boring B-1 at 7.5 feet 100 210 998 8.1 Boring B-1 at 15 feet 400 180 4,055 9.1 Boring B-2 at 15 feet 0 120 3,646 8.6 Boring B-3 at 7.5 feet 0 150 3,821 9.1 Boring B-4 at 5 feet 0 180 2,220 8.6

Boring B-5 at 10 feet 0 180 2,468 8.7 Boring B-6 at 20 feet 0 210 2,722 8.6 Boring B-8 at 5 feet 400 120 2,779 8.7

Boring B-9 at 7.5 feet 0 150 1,814 8.5 *Resistivity was calculated by taking the inverse of the electroconductivity laboratory results.

6.0 LIMITATIONS

DOWL based the conclusions and recommendations presented in this report, based on the assumption that site conditions are not substantially different from those exposed by the explorations. If, during construction, subsurface conditions are different from those encountered in the explorations, advise DOWL at once to review those conditions and reconsider recommendations if necessary. The geotechnical recommendations provided herein are based on the premise that an adequate program of tests and observations will be conducted during construction in order to document compliance with DOWL’s recommendations and to confirm conditions exposed during subgrade preparations. DOWL geotechnical personnel must review final designs to verify that the recommendations provided herein have been properly implemented.

If there is a substantial lapse of time between the submission of this report and the start of work at the site, and especially if conditions have changed due to natural causes or construction operations at or near the site, contact DOWL to review this report and to evaluate the applicability of the conclusions and recommendations presented herein.

DOWL prepared this report for the National Park Service and its Consultants to use on this project.

DOWL recommends you make this report available to prospective contractors for information and factual data only, but not as a warranty of subsurface conditions. DOWL prepared this report, including engineering analyses, recommendations, figures, and design details specifically for the above-referenced site. These recommendations are not applicable to other construction sites. Do not separate the figures from the text for independent use.

DOWL performed these services consistent with the level of care and skill ordinarily exercised by members of the profession currently practicing in this area under similar time and budgetary constraints. No warranty is made or implied.

Any conclusions made by a construction contractor or bidder relating to construction means, methods, techniques, sequences, or costs based upon the information provided in this report are not the responsibility of National Park Service or DOWL.

NPS | Bryce Canyon National Park, Rehabilitate the Main Water System (BRCA318695) NPS Order # 140P2024F091 Project Program | Pre-Design Draft Submittal

7.0 REFERNCES

ACI. (2014). Building Code Requirements for Structural Concrete. American Concrete Institute.

ASCE. (2021). ASCE 7 Hazard Tool. Retrieved August 7, 2020, from https://asce7hazardtool.online/ ASCE. (2021). Minimum Design Loads and Associated Criteria for Buildings and Other

Structures. American Society of Civil Engineers.

Bowers, W. (1990). Geologic map of Bryce Canyon National Park and vicinity. southwestern

Utah: U.S. Geological Survey, Miscellaneous Investigations Series Map I-2108.

FWHA. (2009). Corrosion/Degradation of Soil Reinforcement for Mechanically Stabilized Earth

Walls. Publication No. FHWA-NHI-09-087. Federal Highways Administration.

Hedlund, D., & Olson, J. (1973). Geologic map of the Carpenter Ridge Quadangle, Gunnison

County, Colorado. Denver: USGS.

ICC. (2017). 2018 International Building Code. Country Club Hills: International Code Council.

Idriss, R. W. (2006). Liquefaction Susceptibility Criteria for Silts and Clays. Journal of

Geotechnical and Environmental Engineering.

Lacroix, Y., & Horn, H. (1973). Direct Determination and Indirect Evaluation of Relative Density and Its Use on Earthwork Construction Projects: in Evaluation of Relative Density and Its Role in Geotechnical Projects involving Cohesionless Soils. ASTM Special Technical Publication 523, 251-280.

Shannon and Wilson, I. (December 2021). Pavement Design Report, National Park Service, Bryce Canyon Roundabouts. Garfield County, Utah.

USGS. (2018). Earthquake Hazards - Quaternary Fault and Fold Database of the United States.

Retrieved a b, 2021, from https://www.usgs.gov/natural-hazards/earthquake-hazards/faults?qt-science_support_page_related_con=4#qt-science_support_page_related_con

USGS. (2024, 5 23). National Water Information System: Web Interface. Retrieved from USGS Water Resources: https://waterdata.usgs.gov/co/nwis/

Appendix A - Exploration Logs

Existing Bore Log (Shannon and Wilson, 2021)

Appendix B - Photograph Log

Appendix C - Laboratory Test Results chlorides pH

(ft) (%) LL PL PI gravel sand silt clay pcf percent ppm

B-1 DS16 CL 5-6.5 22.2% 34 17 17 2.3 9.5 34.9 53.3

B-1 DS17 SC 7.5-9 13.4% 0.010 0.021 398 8.1

B-1 DS19 SC-SM 15-15.7 11.9% 0.040 0.018 98 9.1

B-2 DS20 SC 2.5-4 16.8% 18.2 32.9 25.1 23.8 108.2

B-2 DS24 SC 15-16.5 11.0% 0.000 0.012 109 8.6

B-3 DS29 SC-SM 7.5-9 2.9% 0.000 0.015 104 9.1

B-3 DS31 SM 15-16.5 5.5% 17 14 3 20.0 67.6

B-4 DS12 GP 5-6.5 8.0% 125.4 0.000 0.018 179 8.6

B-4 DS13 CL 7.5-9 8.4% 21 13 8 0.1 15.9

B-5 DS44 SC 10-11.5 7.8% 0.000 0.018 161 8.7

B-5 DS45 CL 15-16.5 16.6% 24 14 10 0.4 16.5 43.5 39.5

B-5 DS46 SC-SM 20-21.5 9.8%

B-6 DS36 CL 7.5-9 16.0% 28 16 12 14.6 32.4 53.0 16.0

B-6 DS38 CL 15-16.5 15.2% 23 14 9 3.9 24.2

B-6 DS39 SC-SM 20-21.5 6.9% 0.000 0.021 146 8.6

B-7 DS09 CL 7.5-9 20.7% 30 16 14 0.7 5.6 102.0

B-8 DS05 SC-SM 2.5-4 9.0% 25 20 5 7.9 56.6 93.5

B-8 DS06 SC 5-6.5 5.0% 0.040 0.012 143 8.7

B-9 BS01 CL 2-8 - 25 16 9 10.4 24.2 30.3 35.1

B-9 DS03 CL 7.5-9 18.8% 104.1 0.000 0.015 219 8.5

12.4

71.9

93.7

35.5

Dry Density electro-conduc-tivity water soluble sulfates

**LL = Liquid Limit, PL = Plastic Limit, PI = Plasticity Index, NP = Non-Plastic

Moisture content

Sieve Analysis Atterberg Limits** %

Soil Chemistry

84.0

*DS## = Standard Penetration Test or Drive Sample, BS## = Bucket Sample

Laboratory Results Summary for Bryce Canyon Waterline

Borehole

Sample

USCS

Classifi-cation

Sample Depth

% Fines%

Particle Size Distribution P

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 2.3 2.1 2.9 4.5 34.9 53.3 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140, Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test (ASTM D7928) USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

light brown to black-red LEAN CLAY 17 34 17

3/4" 1/2" 3/8" #4

#10 #16 #40

#100 #200

0.0260 mm.

0.0188 mm.

0.0100 mm.

0.0073 mm.

0.0054 mm.

0.0029 mm.

0.0013 mm.

100.0 99.6 98.9 97.7 95.6 94.5 92.7 90.7 88.2 77.2 73.7 68.9 62.0 55.1 37.8 22.6

0.1118 0.0522

0.0067 0.0045

7/8/24 MJ

0.0019

Natural Moisture Content = 22.2%

CL

7/9/24 MJ

6/24-26/24

6/28/24

SJ

Lab Manager

DOWL/NPS

Bryce Canyon Waterline Bryce Canyon National Park

2024-033-GEO

PL= LL= PI=

D90= D85=

D60= D50=

D30= D15=

D10=

Cu= Cc=

Test Notes

Test Date: Technician:

Test Notes

Test Date: Technician:

Date Sampled:

Date Received:

Checked By:

Title:

* (no specification provided)

Source of Sample: B-1 Depth: 5-6.5' Sample Number: DS16

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 18.2 11.3 10.7 10.9 25.1 23.8 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140, Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test (ASTM D7928) USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

orange to brown clayey SAND with gravel 17 28 11

3/4" 1/2" 3/8" #4

#10 #16 #40

#100 #200

0.0410 mm.

0.0295 mm.

0.0213 mm.

0.0113 mm.

0.0081 mm.

0.0058 mm.

0.0030 mm.

0.0013 mm.

100.0 93.6 92.0 81.8 70.5 65.3 59.8 55.5 48.9 41.7 39.2 36.1 31.1 29.6 25.5 19.0 12.9

8.0686 5.8604

0.4425 0.0832

7/8/24 MJ

0.0086 0.0017

SC

7/9/24 MJ

6/24-26/24

6/28/24

SJ

Lab Manager

DOWL/NPS

Bryce Canyon Waterline Bryce Canyon National Park

2024-033-GEO

PL= LL= PI=

D90= D85=

D60= D50=

D30= D15=

D10=

Cu= Cc=

Test Notes

Test Date: Technician:

Test Notes

Test Date: Technician:

Date Sampled:

Date Received:

Checked By:

Title:

* (no specification provided)

Source of Sample: B-2 Depth: 2.5-4' Sample Number: DS20

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 20.0 25.7 32.8 9.1 12.4 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140) Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

very light brown silty SAND with gravel 14 17 3

3/4" 1/2" 3/8" #4 #8

#16 #40

#100 #200

100.0 94.5 90.5 80.0 59.2 39.6 21.5 14.5 12.4

9.1620 6.2799

2.4277 1.7340

7/9/24 SK/MJ

0.7419 0.1686

Natural Moisture Content = 5.5%

SM

6/24-26/24

6/28/24

SJ

Lab Manager

DOWL/NPS

Bryce Canyon Waterline Bryce Canyon National Park

2024-033-GEO

PL= LL= PI=

D90= D85=

D60= D50=

D30= D15=

D10=

Cu= Cc=

Test Notes

Test Date: Technician:

Test Notes

Test Date: Technician:

Date Sampled:

Date Received:

Checked By:

Title:

* (no specification provided)

Source of Sample: B-3 Depth: 15-16.5' Sample Number: DS31

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 0.1 1.9 2.8 11.2 84.0 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140) Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

yellowish-orange LEAN CLAY with sand 13 21 8

3/8" #4

#10 #40

#100 #200

100.0 99.9 98.0 95.2 91.2 84.0

0.1299 0.0824

Natural Moisture Content = 8.4%

CL

6/24-26/24

6/28/24

SJ

Lab Manager

DOWL/NPS

Bryce Canyon Waterline Bryce Canyon National Park

2024-033-GEO

PL= LL= PI=

D90= D85=

D60= D50=

D30= D15=

D10=

Cu= Cc=

Test Notes

Technician:

Test Notes

Test Date: Technician:

Date Sampled:

Date Received:

Checked By:

Title:

* (no specification provided)

Source of Sample: B-4 Depth: 7.5-9' Sample Number: DS13

SK/MJTest Date: 7/9/24

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 0.4 0.3 1.0 15.2 43.6 39.5 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140, Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test (ASTM D7928) USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

light yellowish brown LEAN CLAY with sand 14 24 10

1/2" 3/8" #4

#10 #16 #40

#100 #200

0.0395 mm.

0.0284 mm.

0.0207 mm.

0.0112 mm.

0.0081 mm.

0.0058 mm.

0.0030 mm.

0.0013 mm.

100.0 99.8 99.6 99.3 98.9 98.3 92.7 83.1 70.2 66.6 60.8 49.3 45.7 42.1 29.2 19.2

0.1184 0.0841

0.0198 0.0117

7/8/24 MJ

0.0032

Natural Moisture Content = 16.6%

CL

7/9/24 MJ

6/24-26/24

6/28/24

SJ

Lab Manager

DOWL/NPS

Bryce Canyon Waterline Bryce Canyon National Park

2024-033-GEO

PL= LL= PI=

D90= D85=

D60= D50=

D30= D15=

D10=

Cu= Cc=

Test Notes

Test Date: Technician:

Test Notes

Test Date: Technician:

Date Sampled:

Date Received:

Checked By:

Title:

* (no specification provided)

Source of Sample: B-5 Depth: 15-16.5' Sample Number: DS45

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 9.0 11.7 8.4 11.0 10.7 49.2 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140) Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

very light brown silty, clayey SAND with gravel 15 21 6

1.5" 1"

3/4" 1/2" 3/8" #4 #8

#16 #40

#100 #200

100.0 95.5 91.0 87.3 85.0 79.3 72.6 65.7 59.9 53.0 49.2

17.4992 9.5331

0.4299 0.0867

7/9/24 SK/MJ

Natural Moisture Content = 9.8%

SC-SM

6/24-26/24

6/28/24

SJ

Lab Manager

DOWL/NPS

Bryce Canyon Waterline Bryce Canyon National Park

2024-033-GEO

PL= LL= PI=

D90= D85=

D60= D50=

D30= D15=

D10=

Cu= Cc=

Test Notes

Test Date: Technician:

Test Notes

Test Date: Technician:

Date Sampled:

Date Received:

Checked By:

Title:

* (no specification provided)

Source of Sample: B-5 Depth: 20-21.5' Sample Number: DS46

E R

C E

N T

F

IN

E R

GRAIN SIZE - mm.

0.0010.010.1110

% +3" Coarse

% Gravel

Fine Coarse Medium

% Sand

Fine Silt

% Fines

Clay

0.0 0.0 14.6 8.0 11.0 13.4 53.0 in in

½ in in

¾ in

½ in

/8 in

Test Results (ASTM D6913 & D1140) Material Description Atterberg (ASTM D4318)

Coefficients

Sieve Test (ASTM D6913 & D1140)

Hydrometer Test USCS (ASTM D2487)

Client:

Project:

Project No:

Sieve Size or

Diam. (mm.)

Finer

Spec.*

Out of Spec.

reddish brown sandy LEAN CLAY 16 28 12

3/4" 1/2" 3/8" #4

#10 #16 #40

#100 #200

100.0 98.2 96.2 85.4 77.4…