B08_Attachment_7_Geotech_Replace_Primary_Park_Water_Systems_FINAL.pdf

REPORT COVER PAGE

Geotechnical Engineering Report

Replace Primary Park Water Systems

10 Organ Pipe Drive

Ajo, Arizona March 29, 2022

Terracon Project No. 63225009

Prepared for:

AJC Architects PC

Salt Lake City, Utah

Prepared by:

Terracon Consultants, Inc.

Tucson, Arizona

Terracon Consultants, Inc. 355 S. Eucl id Ave. Suite 107 Tucson, Ar izona 85719

P [520] 770-1789 F [520] 792-2539 terracon.com

REPORT COVER LETTER TO SIGN

March 29, 2022

AJC Architects PC

703 East 1700 South

Salt Lake City, Utah 84105

Attn: Ms. Jill Jones

P: (801) 466.8818

E: jjones@ajcarchitects.com

Re: Geotechnical Engineering Report

Replace Primary Park Water Systems

Organ Pipe National Monument

10 Organ Pipe Drive

Ajo, Arizona

Terracon Project No. 63225009

Dear Ms. Jones:

Terracon Consultants, Inc. (Terracon) has completed the Geotechnical Engineering services for the above referenced project. This study was performed in general accordance with Terracon

Proposal No. P63225009 dated January 20, 2022. This report presents the findings of the subsurface exploration and provides geotechnical engineering recommendations concerning earthwork and the design and construction of foundations for the proposed project.

We appreciate the opportunity to be of service to you on this project. If you have any questions concerning this report or if we may be of further service, please contact us.

Sincerely, Terracon Consultants, Inc.

Louis D. Braun, P.E. Donald R. Clark, P.E.

Geotechnical Group Manager Sr. Consultant/Sr. Principal

Replace Primary Park Water Systems ■ Ajo, Arizona

March 29, 2022 ■ Terracon Project No. 63225009

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REPORT TOPICS

INTRODUCTION

SITE CONDITIONS

PROJECT DESCRIPTION

GEOTECHNICAL CHARACTERIZATION

CORROSIVITY

SEISMIC CONSIDERATIONS

SHALLOW FOUNDATIONS

EARTHWORK

LATERAL EARTH PRESSURES

GENERAL COMMENTS

Note: This report was originally delivered in a web-based format. For more interactive features, please view your project online at client.terracon.com.

ATTACHMENTS

EXPLORATION AND TESTING PROCEDURES

SITE LOCATION AND EXPLORATION PLANS

EXPLORATION RESULTS

SUPPORTING INFORMATION

Note: Refer to each individual Attachment for a listing of contents.

http://client.terracon.com/

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INTRODUC TION

Geotechnical Engineering Report

Replace Primary Park Water Systems

10 Organ Pipe Drive

Ajo, Arizona Terracon Project No. 63225009

March 29, 2022

INTRODUCTION

This report presents the results of our subsurface exploration and geotechnical engineering services performed for the planned Primary Park Water Systems project at the Organ Pipe

National Monument located at 10 Organ Pipe Drive in Ajo, Arizona. The purpose of these services is to provide information and geotechnical engineering recommendations relative to:

■ Subsurface soil/bedrock conditions ■ Foundation design and construction

■ Groundwater conditions ■ Seismic site classification per IBC

■ Site preparation and earthwork

The geotechnical engineering Scope of Services for this project included the advancement of two

(2) test borings to depths ranging from approximately ½ to 11 feet below existing site grades, laboratory testing of samples collected from our field exploration, engineering analyses and the preparation of this geotechnical engineering report. Due to the shallow refusal to auger drilling encountered at the location of Boring B-2, a seismic refraction survey was performed in the area of the proposed tank.

Maps showing the site, boring and survey locations are shown in the Site Location and

Exploration Plan sections, respectively. The results of the laboratory testing performed on soil/rock samples obtained from the site during the field exploration are included in the

Exploration Results section.

SITE CONDITIONS

The following description of site conditions is derived from our site visit in association with the field exploration and our review of publicly available topographic maps.

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Item Description

Location

Information

The proposed water system improvements are located within the Organ Pipe

National Monument located at 10 Organ Pipe Drive in Ajo, Arizona

Approximate GPS Coordinates of:

North Tank: 31.95315°N, 112.81273°W

South Tank: 31.94685°N, 112.81205°W

See Site Location for additional location information.

Existing

Improvements The existing improvements include an existing tank to be replaced at each site.

Current Ground

Cover

The sites are cleared and graded immediately outside the perimeter of the existing tanks, with light to moderately dense vegetation surrounding these areas. Each tank has a driveway with an asphalt driveway extending from the north tank and an unsurfaced driveway extending from the south tank.

Existing

Topography

The sites appear to be relatively flat within the cleared and graded areas although a moderate slope downward towards the east near the north tank and moderate slope downward toward the west near the south tank. We understand previous blasting efforts were used to level each site at both tank locations.

PROJECT DESCRIPTION

Our initial understanding of the project was provided in our proposal and was discussed in the project planning stage. A period of collaboration has transpired since the project was initiated, and our final understanding of the project conditions is as follows:

Item Description

Project Description and

Tank Construction

The project will replace the water distribution system at Organ Pipe Cactus

National Monument, including replacement of asbestos cement pipe, two water storage tanks, the supply well, and various system components.

These geotechnical services are specific to the tank replacements. Tank replacement of a 50,000-gallon and 100,000-gallon tank is anticipated to be with glass fused to steel tanks.

Maximum loads Not provided.

Grading Based on the information provided, we understand the grade of the tanks will remain nearly the same as that currently existing at each location.

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GEOTECHNICAL CHARACTERIZATION

Geology

The project area is located in the Basin and Range physiographic province (1Cooley, 1967) of the

North American Cordillera (2Stern, et al, 1979) of the southwestern United States. The southern portion of the Basin and Range province is situated along the southwestern flank of the Colorado

Plateau and is bounded by the Sierra Nevada Mountains to the west. Formed during middle and late Tertiary time (100 to 15 m.y. ago), the Basin and Range province is dominated by fault-controlled topography. The topography consists of mountain ranges and relatively flat alluviated valleys. These mountain ranges and valleys have evolved from generally complex movements and associated erosional and depositional processes.

Typically, the ranges in this area are of small areal extent but protrude significantly above adjacent wide alluviated plains and valleys. The basin rims are formed by the mountain ranges which consist of sedimentary, igneous and metamorphic materials which have been subjected to recurrent faulting and tilting, and in some places volcanic and intrusive events. As a result of erosion, the valleys have experienced partial infilling with sedimentary material which has been deposited as alluvial fans. Occasionally, the valleys may become interlocking as a result of coalescing alluvial fans which are referred to as bajadas.

Surficial geologic conditions mapped at the site (3Richard, et al, 2000) consist of Jurassic volcanic rocks, described as massive quartz-feldspar porphyry, generally interpreted as thick, welded rhyolitic tuffs, with locally abundant lava, and sandstone and conglomerate derived from volcanic rocks. Rare eolian quartzite units are interbedded in southern Arizona. The rock includes the Ali

Molina Formation, Mount Wrightson Formation, part of the Canelo Hills Volcanics, Cobre Ridge tuff, Black Rock volcanics, Planet Volcanics, and equivalent rocks. (160-200 Ma)

Subsurface Profile

Specific conditions encountered at the boring locations are indicated on the individual boring logs presented in the attached Exploration Results. Stratification boundaries on the boring logs represent the approximate location of changes in soil/rock types; in-situ, the transition between materials may be gradual. Based on conditions encountered in the borings, subsurface conditions on the project site can be generalized as follows:

1Cooley, M.E., 1967, Arizona Highway Geologic Map, Arizona Geological Society.

2Stern, C.W., et al, 1979, Geological Evolution of North America, John Wiley & Sons, Santa Barbara, California.

3 Richard, S. M., Reynolds, S.J., Spencer, J. E., and Pearthree, P. A., 2000, Geologic Map of Arizona:

Arizona Geological Survey Map 35, 1 sheet, scale 1:1,000,000.

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Description Approximate Depth to

Bottom of Stratum (feet) Material Encountered Strength

Stratum 1 ½ to 11 Weathered Volcanic Bedrock Medium Strong

Seismic Refraction Survey

Due to the shallow auger refusal encountered on bedrock at the location of Boring B-2, one (1) seismic refraction survey was conducted at the site on February 22, 2022 in a north-south orientation. The seismic refraction survey utilized a 24-geophone spread, 36 feet in total length, with approximate 1½-foot geophone spacings. The geophysical data was acquired with a

Geometrics ES-3000 seismograph.

A total of eight shots (signal generation points) were conducted at the seismic line, spread evenly throughout the total line length. The refraction method requires that subsurface velocities increase with depth. A layer having a velocity lower than that of the layer above will not be detectable by the seismic refraction method and, therefore, could lead to errors in the depth calculations of subsequent layers.

Collected P-wave data was assessed in the field from hard copy seismograph records and later processed in the office using Rayfract (Intelligent Resources, Inc.) which uses a smooth inversion technique to deliver reliable seismic processing. The product of the seismic processing is a two -dimensional plot of seismic p-wave velocity versus depth. Seismic layer velocities are calculated from time-distance (TD) plots. Delays in arrival times per each seismic layer are revealed as small offsets in arrival times between geophones without a significant change in the slope of the layer line on the TD plot. The location of the seismic refraction line, identified as SL-1, is shown on

Exploration Plan in the Attachments. A subsurface profile based on the result of the seismic refraction survey is presented in the Exploration Results. The compressional seismic wave-velocities are indicated on each layer within the profile.

Based on the mapped geology and results of the seismic refraction survey, subsurface conditions at the southern 50K Gallon tank have been generalized as follows:

Description Approximate Depth to

Bottom of Stratum (feet) Interpreted Material

Approximate P-Wave

Velocity (ft/sec)

Stratum 1 ½ to 4½ Weathered Volcanic Bedrock 4,820

Stratum 2 9½ Competent Volcanic Bedrock 11,487

Groundwater Conditions

Groundwater was not observed in any of the test borings at the time of field exploration. These observations represent groundwater conditions at the time of the field exploration and may not be

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Based on information obtained from the Arizona Department of Water Resources – Groundwater

Data website (https://azwatermaps.azwater.gov/gwsi), the depth to regional groundwater was measured in 2021 to be approximately 354 feet below the ground surface (or an elevation of approximately 1,306 feet above mean sea level, AMSL) at an Arizona Department of Water

Resources (ADWR) monitored well site (Local ID: C-17-05 17ABC2UNSURV) located approximately 2/3 mile southwest of the north tank location and 2/3 mile northwest of the south tank location.

Frost Considerations

The site is not considered to be frost susceptible and frost depth is not a design consideration.

CORROSIVITY

The following table lists the results of laboratory performed to evaluate the corrosive characteristics of the on-site rock/soils.

Boring

No.

Sample

Depth (feet)

Soluble

Sulfate1 (ppm)

Soluble

Chlorides (ppm) pH

Minimum Resistivity

(ohm-cm)

B-1 0 to 5 <50 <10 9.9 2,400

B-2 0 to ½ <50 <10 10.0 --

1. Results of soluble sulfate testing indicate that a sample of the on-site rock/soils tested has an exposure class of S0 when classified in accordance with Table 4.3.1 of the ACI Design Manual. The results of the testing indicate ASTM Type I portland cement is suitable for project concrete on and below grade. However, if there is no (or minimal) cost differential, use of ASTM Type II portland cement is recommended for additional sulfate resistance of construction concrete. Concrete should be designed in accordance with the provisions of the

ACI Design Manual, Section 318, Chapter 4.

These values should be used to help determine potential corrosive characteristics of the on-site rock/soils with respect to contact with the various underground materials which will be used for project construction. The corrosion information presented is specific to the samples tested. If the actual rock/soils that will be in contact with the structures at the site are different than those tested, then additional corrosion testing should be performed. Terracon is not a corrosion engineer, and our scope of work was limited to performing corrosion laboratory tests on selected samples, presenting these results, and providing a brief comparison of the results to selected criteria. A qualified corrosion engineer should be consulted if corrosion of underground utilities and structures is a concern.

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SEISMIC CONSIDERATIONS

The seismic design requirements for structures are based on Seismic Design Category. Site

Classification is required to determine the Seismic Design Category for a structure. The Site

Classification is based on the upper 100 feet of the site profile defined by a weighted average value of either shear wave velocity, standard penetration resistance, or undrained shear strength in accordance with Section 20.4 of ASCE 7 and the International Building Code (IBC). Based on the soil/bedrock properties encountered at the site and as described on the boring logs, the

Seismic Site Classification is B. Borings at this site were extended to a maximum depth of 11 feet. The site properties below the boring depth to 100 feet were estimated based on our seismic refraction data, our experience and knowledge of geologic conditions of the general area.

Additional deeper borings or geophysical testing may be performed to confirm the conditions below the current boring depth.

SHALLOW FOUNDATIONS

If the site has been prepared in accordance with the requirements noted in Earthwork, the following design parameters are applicable for shallow foundations.

Design Parameters – Alternate Ground Mounted Tanks

A foundation system consisting of a concrete ring beam and footing foundation system can be considered for support of the proposed ground mounted water tanks. The footing foundation should be designed based on the criteria outlined below:

Design Item Description/Recommendation

Foundation Type Ring Beam and Spread Footing Foundation

Bearing Material

Approved undisturbed native rock or newly placed engineered fill, if required to raise site grades as outlined in Earthwork section of this report.

Allowable Bearing Pressure (psf) Any practical value up to 3,000 psf

Minimum Embedment Depth (inches) 12

Total Estimated Settlement at Center of Tank Less than ½ inch

Estimated Differential Movement from Ring

Beam to Center of Tank Less than ¼ inch

Finished grade is defined as the lowest adjacent grade within five feet of the foundation for perimeter. The weight of the foundation concrete below grade may be neglected in dead load computations.

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Footings and the ring beam foundation should be reinforced as necessary to reduce the potential for distress caused by differential foundation movement. Final connections to the tanks should be made after the initial filling.

Foundation excavations should be observed by the geotechnical engineer. If the rock/soil conditions encountered differ significantly from those presented in this report, supplemental recommendations will be required.

Design Parameters – Alternate Ground Mounted Tanks

An alternate foundation system consisting of a steel ring confined gravel mat could be considered for support of the proposed ground mounted water tanks. Typically, these systems are constructed with a confining ring approximately 12 to 24 inches outside the perimeter of the tank bottom. The surface of the gravel mat and the confining ring are essentially constructed at the grade of the tank pad. We recommend the gravel mat and the confining ring be a minimum of 12 inches in depth. If the 12 inches required is excavated into the rock at the site, no confining ring will need to be utilized.

If this alternative foundation system is utilized, we recommend the gravel mat be constructed with aggregate base course material meeting the specifications of the Pima Association of

Governments (PAG), or similar local governing specification. The gravel mat should be compacted to a minimum of 100% of the maximum density determined in accordance with standard Proctor criteria, ASTM D698.

Design horizontal stresses over the entire depth of the perimeter confining ring, caused by tank live and dead loads, can be assumed conservatively at about 45% of the vertical stress imposed at the floor level of the reservoir. Lateral earth pressure for the at-rest condition should be included in the design analysis of the confining ring if the tank is placed on engineered fill soils.

To reduce the potential effects and pressures caused by compaction, placement simultaneously at the same levels on the interior and exterior sides of the confining ring should be specified in the design plans.

EARTHWORK

The following recommendations include site preparation, excavation, subgrade preparation and placement of engineered fills on the project. The recommendations presented for design and construction of earth supported elements including foundations are contingent upon following the recommendations outlined in this section.

Earthwork on the project should be observed and evaluated by Terracon. The evaluation of earthwork should include observation and testing of engineered fill, subgrade preparation, Responsive ■ Resourceful ■ Reliable 8 foundation bearing rock/soils, and other geotechnical conditions exposed during the construction of the project.

Site and Subgrade Preparation

Demolition of the existing water tanks to be removed should include complete removal within the proposed construction area. This should include removal of any backfill found adjacent to utilities, and any soils disturbed during demolition activities. All materials derived from the demolition of existing tanks should be removed from the site and not be allowed for use as on-site fill.

The proposed tanks may be supported on shallow foundations bearing directly on approved undisturbed native rock/soil or newly placed engineered fill, if required to raise site grades.

Although evidence of fill was not observed during the site reconnaissance, such features may be encountered during construction or demolition of the existing tanks. If any unexpected underground facilities are encountered, such features should be removed, and the excavation thoroughly cleaned prior to backfill placement and/or construction.

Excavation

It is anticipated that shallow excavations for the proposed construction on this project will require heavier construction equipment capable of excavating medium strong weathered bedrock. We understand blasting was previously used to bring each site to the current grades.

The individual contractor(s) is responsible for designing and constructing stable, temporary excavations as required to maintain stability of both the excavation sides and bottom. As a minimum, excavations should be performed in accordance with OSHA 29 CFR, Part 1926, Subpart

P, “Excavations” and its appendices, and in accordance with any applicable local, and/or state regulations.

Fill Material Types

All fill materials should be inorganic soils free of vegetation, debris, and fragments larger than 6 inches in size. Pea gravel or other similar non-cementatious, poorly-graded materials should not be used as fill or backfill without the prior approval of the geotechnical engineer.

Imported soils (if required) for use as fill material within proposed tank areas should conform to low volume change materials as indicated in the following specifications:

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Percent Finer by Weight

Gradation (ASTM C 136)

6"

3” .................................................................................................... 70-100

No. 4 Sieve ..................................................................................... 50-100

No. 200 Sieve .............................................................................. 50 (max)

◼ Liquid Limit ....................................................................... 30 (max)

◼ Plasticity Index ................................................................. 15 (max)

◼ Maximum expansive potential (%)* ............................................ 1.5

*Measured on a sample compacted to approximately 95 percent of the ASTM D698 maximum dry density at optimum water content. The sample is confined under a 100 psf surcharge and submerged/inundated.

Engineered fill should be placed and compacted in horizontal lifts, using equipment and procedures that will produce recommended moisture contents and densities throughout the lift.

Fill lifts should not exceed 10 inches loose thickness.

Aggregate base course material specifications for the project should be in accordance with the requirements and specifications of the Pima Association of Governments (PAG), or similar local governing specification.

Fill Compaction Requirements

Recommended compaction and moisture content criteria for engineered fill materials are as follows:

Material Type and Location

Per the Standard Proctor Test (ASTM D 698)

Minimum Compaction

Requirement (%)

Range of Moisture Contents for Compaction

Minimum Maximum

Approved imported fill soils:

Beneath Foundations 95 -3% +3%

For Fills Greater than 5 feet Below Finished Grade 98 -3% +3%

Aggregate Base (beneath tanks) 100 -3% +3%

Trench Backfill 95 -3% +3%

Miscellaneous Backfill 95 -3% +3%

Grading and Drainage

All finished grades must provide effective drainage away from the structures during and after construction and should be maintained throughout the life of the structures.

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Construction Observation and Testing

The earthwork efforts should be monitored under the direction of the Geotechnical Engineer. In addition to the documentation of the essential parameters necessary for construction, the continuation of the Geotechnical Engineer into the construction phase of the project provides the continuity to maintain the Geotechnical Engineer’s evaluation of subsurface conditions, including assessing variations and associated design changes.

LATERAL EARTH PRESSURES

Design Parameters

The following lateral earth pressure parameters are presented for use in the design of foundations at the site. These values are based on using the import sand soils as fill and backfill material.

For soils above any free water surface, recommended equivalent fluid pressures for unrestrained foundation elements are:

Earth Pressure Design Case Design Recommendation

2,4

Active Case (Ka) 35 psf/ft

Passive Case (Kp) 440 psf/ft

At-Rest Case (Ko)

55 psf/ft

Coefficient of Base Friction 0.45

1. For active earth pressure, wall must rotate about base, with top lateral movements 0.002 H to 0.004 H, where H is wall height. For passive earth pressure, wall must move horizontally to mobilize resistance.

2. The design values are based on utilizing import soils as backfill placed and compacted as outlined in the

Earthwork section of this report. Compaction of each lift adjacent to walls should be accomplished with hand-operated tampers or other lightweight compactors.

3. The coefficient of base sliding should be reduced to 0.35 when used in conjunction with passive pressure.

4. The lateral earth pressures and coefficient of base friction herein do not include any factor of safety, they assume drained conditions, and they are not applicable for submerged soils/hydrostatic loading. Additional recommendations may be necessary if such conditions are to be included in the design.

5. The lateral earth pressure for the at-rest case for the gravel against the confining ring if the steel ring confined gravel mat alternative is chosen can be reduced to 50 psf/ft.

GENERAL COMMENTS

Our analysis and opinions are based upon our understanding of the project, the geotechnical conditions in the area, and the data obtained from our site exploration. Natural variations will occur between exploration point locations or due to the modifying effects of construction or weather.

The nature and extent of such variations may not become evident until during or after construction.

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Terracon should be retained as the Geotechnical Engineer, where noted in the report, to provide observation and testing services during pertinent construction phases. If variations appear, we can provide further evaluation and supplemental recommendations. If variations are noted in the absence of our observation and testing services on-site, we should be immediately notified so that we can provide evaluation and supplemental recommendations.

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

Our services and any correspondence or collaboration through this system are intended for the sole benefit and exclusive use of our client for specific application to the project discussed and are accomplished in accordance with generally accepted geotechnical engineering practices with no third-party beneficiaries intended. Any third-party access to services or correspondence is solely for information purposes to support the services provided by Terracon to our client.

Reliance upon the services and any work product is limited to our client and is not intended for third parties. Any use or reliance of the provided information by third parties is done solely at their own risk. No warranties, either express or implied, are intended or made.

Site characteristics as provided are for design purposes and not to estimate excavation cost. Any use of our report in that regard is done at the sole risk of the excavating cost estimator as there may be variations on the site that are not apparent in the data that could significantly impact excavation cost. Any parties charged with estimating excavation costs should seek their own site characterization for specific purposes to obtain the specific level of detail necessary for costing.

Site safety, and cost estimating including, excavation support, and dewatering requirements/design are the responsibility of others. If changes in the nature, design, or location of the project are planned, our conclusions and recommendations shall not be considered valid unless we review the changes and either verify or modify our conclusions in writing.

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ATTACHMENTS

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EXPLORATION AND TESTING PROCEDURES

Field Exploration

The field exploration for this project consisted of the following boring program:

Number of Borings Boring Depth (feet) 1 Location

1 11 50K Gallon Tank

1 ½ 100K Gallon Tank

1. Auger refusal was encountered in both borings at the depths outline above on volcanic bedrock.

Boring Layout and Elevations: Terracon personnel provided a boring layout outlining the location of the borings measuring from existing site features. Coordinates were obtained with a handheld GPS unit (estimated horizontal accuracy of about ±20 feet) and approximate elevations were obtained by interpolation from Google Earth Pro.

Subsurface Exploration Procedures: The borings were advanced with truck-mounted CME-75, rotary drill rigs using continuous 7-inch diameter hollow stem flight augers. A continuous lithologic log of each boring was recorded by the field engineer during the drilling operations. At selected intervals, samples of the subsurface materials were taken by driving a split-spoon (SPT) sampler.

Bulk samples of subsurface materials were also obtained from auger cuttings.

In the split-spoon sampling procedure, the number of blows required to advance a standard 2-inch

O.D. split-barrel-sampler the last 12 inches of the typical total 18-inch penetration by means of a

140-pound C.M.E. auto-hammer with a free fall of 30 inches, is the standard penetration resistance value (SPT-N). The penetration resistance is used to estimate the strength of the bedrock.

Our exploration team prepared field boring logs as part of the drilling operations. The sampling depths, penetration distances, and other sampling information were recorded on the field logs.

These field logs included visual classifications of the materials encountered during drilling and our interpretation of the subsurface conditions between samples. The samples were placed in appropriate containers and taken to our laboratory for testing and classification by a geotechnical engineer. Final boring logs were prepared from the field logs. The final boring logs represent the geotechnical engineer's interpretation of the field logs and include modifications based on observations.

One (1) seismic refraction test line was completed near B-2 due to shallow auger refusal, and the test line location, identified by SL-1, is depicted on the Exploration Plan. The compressional p-wave velocity profile interpreted along the test line is presented in the Exploration Results section. The methods used for seismic refraction are described in the Seismic Refraction

Survey section above.

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Laboratory Testing

The project engineer reviewed the field data and assigned laboratory tests to understand the corrosivity properties of the various rock strata, as necessary, for this project. Laboratory tests were performed in general accordance with the applicable ASTM, local or other accepted standards.

Selected samples obtained from the site were tested for the following engineering properties:

■ pH

■ Minimum Resistivity

■ Soluble Sulfates

■ Soluble Chlorides

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SITE LOCATION AND EXPLORATION PLANS

Contents:

Site Location Plan

Exploration Plan

Note: All attachments are one page unless noted above.

SITE LOCATION

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MAP 1 PORTRA IT

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

SITE LOCATION

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MAP 2 PORTRA IT

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

EXPLORATION RESULTS

Boring Logs (B-1 and B-2, 2 pages)

Summary of Laboratory Results

P-Wave Velocity Profile

50/6"

8-50/6"

50/1"

WEATHERED VOLCANIC BEDROCK, light gray, highly weathered, medium strong

Auger Refusal on Bedrock at 11 Feet

11.0 1894+/-

Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.

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LOCATION See Exploration Plan

Latitude: 31.9532° Longitude: -112.8119°

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DEPTH ELEVATION (Ft.)

Approximate Surface Elev.: 1905 (Ft.) +/-

Advancement Method:

Hollow Stem Auger

Abandonment Method:

Boring backfilled with auger cuttings upon completion.

Notes:

Project No.: 63225009

Drill Rig: CME 75

BORING LOG NO. B-1

AJC Architects PCCLIENT:

Salt Lake City, Utah

Driller: GSI

Boring Completed: 02-22-2022

PROJECT: Replace Primary Park Water Systems

Elevations were interpolated from Google Earth Pro.

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

See Supporting Information for explanation of symbols and abbreviations.

10 Organ Pipe Drive Ajo, Arizona

SITE:

Boring Started: 02-22-2022

355 S Euclid Ave, Ste 107 Tucson, AZ

WATER LEVEL OBSERVATIONS

Groundwater not encountered

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WEATHERED VOLCANIC BEDROCK, light gray, highly weathered, medium strong

Auger Refusal on Bedrock at 0.5 Foot

0.5 1826.5+/-

Hammer Type: AutomaticStratification lines are approximate. In-situ, the transition may be gradual.

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LOCATION See Exploration Plan

Latitude: 31.9468° Longitude: -112.8119°

G R

A P

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IC

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DEPTH ELEVATION (Ft.)

Approximate Surface Elev.: 1827 (Ft.) +/-

Advancement Method:

Hollow Stem Auger

Abandonment Method:

Boring backfilled with auger cuttings upon completion.

Notes:

Project No.: 63225009

Drill Rig: CME 75

BORING LOG NO. B-2

AJC Architects PCCLIENT:

Salt Lake City, Utah

Driller: GSI

Boring Completed: 02-22-2022

PROJECT: Replace Primary Park Water Systems

Elevations were interpolated from Google Earth Pro.

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

See Supporting Information for explanation of symbols and abbreviations.

10 Organ Pipe Drive Ajo, Arizona

SITE:

Boring Started: 02-22-2022

355 S Euclid Ave, Ste 107 Tucson, AZ

WATER LEVEL OBSERVATIONS

Groundwater not encountered

S A

M P

LE

T

Y P

E

B-1 0.0 - 5.0 9.9 2400 <50 <10 2

B-2 0.0 - 0.5 10.0 <50 <10 2

Dry Density (pcf)

Water Content (%)

Passing #200

Sieve (%) LL PL

REMARKS

1. Dry Density and/or moisture determined from one or more rings of a multi-ring sample.

2. Visual Classification.

3. Submerged to approximate saturation.

4. Expansion Index in accordance with ASTM D4829-95.

5. Air-Dried Sample

Borehole No.

Depth (ft.)

USCS

Soil

Class.

In-Situ Properties Classification

Atterberg Limits

Expansion Testing Corrosivity

Remarks

PI

Dry Density

(pcf)

Water Content

Surcharge (psf)

Expansion

Expansion Index

EI

pH Resistivity

(ohm-cm) Sulfates (ppm)

Chlorides (ppm)

SUMMARY OF LABORATORY RESULTS

PROJECT: Replace Primary Park Water Systems PROJECT NUMBER: 63225009

CLIENT: AJC Architects PC Salt Lake City, Utah

SITE: 10 Organ Pipe Drive Ajo, Arizona

PH. 520-770-1789 FAX. 520-792-2539

355 S Euclid Ave, Ste 107 Tucson, AZ

EXHIBIT: B-1T

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Project Manager:

Drawn by:

Checked by:

Approved by:

Project No.

File Name:

Date:

Not to Scale Scale:

P-WAVE VELOCITY PROFILE: SL-1

LB

Seismic

3/10/2021

63225009

North South

Replace Primary Park Water Systems Organ Pipe National Monument, Ajo, AZ SL-1 ldbraun Stamp

SUPPORTING INFORMATION

General Notes

Unified Soil Classification System

Description of Rock Properties

Water levels indicated on the soil boring logs are the levels measured in the borehole at the times indicated.

Groundwater level variations will occur over time. In low permeability soils, accurate determination of groundwater levels is not possible with short term water level observations.

No Recovery

Modified Dames & Moore Ring Sampler

Grab Sample

Modified California

Ring Sampler

GENERAL NOTES

4 - 8

Unconfined Compressive Strength, Qu, psf

S T

R E

N G

T H

T E

R M

S

Over 12 in. (300 mm) 12 in. to 3 in. (300mm to 75mm) 3 in. to #4 sieve (75mm to 4.75 mm) #4 to #200 sieve (4.75mm to 0.075mm Passing #200 sieve (0.075mm)

Particle Size

RELATIVE DENSITY OF COARSE-GRAINED SOILS

< 5 5 - 12 > 12

Percent of Dry Weight

Descriptive Term(s) of other constituents

RELATIVE PROPORTIONS OF FINES

1 - 10 11 - 30

> 30

Plasticity Index

S A

M P

L

IN

G

LOCATION AND ELEVATION NOTES

> 99 4,000 to 8,000

2,000 to 4,000

Macro Core

1,000 to 2,000

500 to 1,000 less than 500

Stiff59 - 98

19 - 5810 - 29

Soft7 - 18

Very Soft0 - 60 - 3Very Loose

Hard

(More than 50% retained on No. 200 sieve.)

Density determined by Standard Penetration Resistance

Includes gravels, sands and silts.

Percent of Dry Weight

Major Component of Sample

Water Level After a Specified Period of Time

Water Initially Encountered

Descriptive Term(s) of other constituents

< 15 15 - 29 > 30

Term

PLASTICITY DESCRIPTION

8 - 15

Rock Core

Split SpoonShelby Tube

W A

T E

R L

E V

E L

30 - 50

5 - 9Medium-Stiff

3 - 42 - 44 - 9

< 30 - 1

Very Dense

Dense

Medium Dense

Ring Sampler Blows/Ft.

Ring Sampler Blows/Ft.

Standard Penetration or N-Value

Blows/Ft.

Very Stiff

Loose

Descriptive Term (Consistency)

Standard Penetration or N-Value

Blows/Ft.

Trace With Modifier

RELATIVE PROPORTIONS OF SAND AND GRAVEL GRAIN SIZE TERMINOLOGY

Water Level After a Specified Period of Time

Trace With Modifier

Bulk

Soil classification is based on the Unified Soil Classification System. Coarse Grained Soils have more than 50% of their dry weight retained on a #200 sieve; their principal descriptors are: boulders, cobbles, gravel or sand. Fine Grained Soils have less than 50% of their dry weight retained on a #200 sieve; they are principally described as clays if they are plastic, and silts if they are slightly plastic or non-plastic. Major constituents may be added as modifiers and minor constituents may be added according to the relative proportions based on grain size. In addition to gradation, coarse-grained soils are defined on the basis of their in-place relative density and fine-grained soils on the basis of their consistency.

Unless otherwise noted, Latitude and Longitude are approximately determined using a hand-held GPS device. The accuracy of such devices is variable. Surface elevation data annotated with +/- indicates that no actual topographical survey was conducted to confirm the surface elevation. Instead, the surface elevation was approximately determined from topographic maps of the area.

> 8,000

DESCRIPTIVE SOIL CLASSIFICATION

(50% or more passing the No. 200 sieve.)

Consistency determined by laboratory shear strength testing, field visual-manual procedures or standard penetration resistance

(HP)

(T)

(b/f)

N

(PID)

(OVA)

Hand Penetrometer

Torvane

Standard Penetration Test (blows per foot)

N value

Photo-Ionization Detector

Organic Vapor Analyzer

CONSISTENCY OF FINE-GRAINED SOILS

> 42> 30

19 - 4215 - 30> 50

10 - 18

Boulders Cobbles Gravel Sand Silt or Clay

Non-plastic Low Medium High

Descriptive Term (Density)

DESCRIPTION OF SYMBOLS AND ABBREVIATIONS

F

IE

L D

T E

S T

S

UNIFIED SOIL CLASSIFICATION SYSTEM

Criteria for Assigning Group Symbols and Group Names Using Laboratory Tests A Soil Classification

Group Symbol Group Name B

Coarse Grained Soils:

More than 50% retained on No. 200 sieve

Gravels:

More than 50% of coarse fraction retained on No. 4 sieve

Clean Gravels:

Less than 5% fines C

Cu 4 and 1 Cc 3 E GW Well-graded gravel F Cu 4 and/or 1 Cc 3 E GP Poorly graded gravel F

Gravels with Fines:

More than 12% fines C

Fines classify as ML or MH GM Silty gravel F,G,H Fines classify as CL or CH GC Clayey gravel F,G,H

Sands:

50% or more of coarse fraction passes No. 4 sieve

Clean Sands:

Less than 5% fines D

Cu 6 and 1 Cc 3 E SW Well-graded sand I Cu 6 and/or 1 Cc 3 E SP Poorly graded sand I

Sands with Fines:

More than 12% fines D

Fines classify as ML or MH SM Silty sand G,H,I Fines classify as CL or CH SC Clayey sand G,H,I

Fine-Grained Soils:

50% or more passes the No. 200 sieve

Silts and Clays:

Liquid limit less than 50

Inorganic:

PI 7 and plots on or above “A” line J CL Lean clay K,L,M PI 4 or plots below “A” line J ML Silt K,L,M

Organic:

Liquid limit - oven dried

0.75 OL

Organic clay K,L,M,N

Liquid limit - not dried Organic silt K,L,M,O

Silts and Clays:

Liquid limit 50 or more

Inorganic:

PI plots on or above “A” line CH Fat clay K,L,M PI plots below “A” line MH Elastic Silt K,L,M

Organic:

Liquid limit - oven dried

0.75 OH

Organic clay K,L,M,P

Liquid limit - not dried Organic silt K,L,M,Q Highly organic soils: Primarily organic matter, dark in color, and organic odor PT Peat

A Based on the material passing the 3-inch (75-mm) sieve B If field sample contained cobbles or boulders, or both, add “with cobbles or boulders, or both” to group name.

C Gravels with 5 to 12% fines require dual symbols: GW-GM well-graded gravel with silt, GW-GC well-graded gravel with clay, GP-GM poorly graded gravel with silt, GP-GC poorly graded gravel with clay.

D Sands with 5 to 12% fines require dual symbols: SW-SM well-graded sand with silt, SW-SC well-graded sand with clay, SP-SM poorly graded sand with silt, SP-SC poorly graded sand with clay

E Cu = D60/D10 Cc =

DxD

)(D

F If soil contains 15% sand, add “with sand” to group name.

G If fines classify as CL-ML, use dual symbol GC-GM, or SC-SM.

H If fines are organic, add “with organic fines” to group name.

I If soil contains 15% gravel, add “with gravel” to group name.

J If Atterberg limits plot in shaded area, soil is a CL-ML, silty clay.

K If soil contains 15 to 29% plus No. 200, add “with sand” or “with gravel,” whichever is predominant.

L If soil contains 30% plus No. 200 predominantly sand, add “sandy” to group name.

M If soil contains 30% plus No. 200, predominantly gravel, add

“gravelly” to group name.

N PI 4 and plots on or above “A” line.

O PI 4 or plots below “A” line.

P PI plots on or above “A” line.

Q PI plots below “A” line.

DESCRIPTION OF ROCK PROPERTIES

ROCK VER SION 1

WEATHERING

Term Description

Unweathered No visible sign of rock material weathering, perhaps slight discoloration on major discontinuity surfaces.

Slightly weathered

Discoloration indicates weathering of rock material and discontinuity surfaces. All the rock material may be discolored by weathering and may be somewhat weaker externally than in its fresh condition.

Moderately weathered

Less than half of the rock material is decomposed and/or disintegrated to a soil. Fresh or discolored rock is present either as a continuous framework or as corestones.

Highly weathered

More than half of the rock material is decomposed and/or disintegrated to a soil. Fresh or discolored rock is present either as a discontinuous framework or as corestones.

Completely weathered

All rock material is decomposed and/or disintegrated to soil. The original mass structure is still largely intact.

Residual soil All rock material is converted to soil. The mass structure and material fabric are destroyed. There is a large change in volume, but the soil has not been significantly transported.

STRENGTH OR HARDNESS

Description Field Identification Uniaxial Compressive Strength, psi (MPa)

Extremely weak Indented by thumbnail 40-150 (0.3-1)

Very weak Crumbles under firm blows with point of geological hammer, can be peeled by a pocket knife

150-700 (1-5)

Weak rock Can be peeled by a pocket knife with difficulty, shallow indentations made by firm blow with point of geological hammer

700-4,000 (5-30)

Medium strong Cannot be scraped or peeled with a pocket knife, specimen can be fractured with single firm blow of geological hammer

4,000-7,000 (30-50)

Strong rock Specimen requires more than one blow of geological hammer to fracture it

7,000-15,000 (50-100)

Very strong Specimen requires many blows of geological hammer to fracture it 15,000-36,000 (100-250)

Extremely strong Specimen can only be chipped with geological hammer >36,000 (>250)

DISCONTINUITY DESCRIPTION

Fracture Spacing (Joints, Faults, Other Fractures) Bedding Spacing (May Include Foliation or Banding)

Description Spacing Description Spacing

Extremely close < ¾ in (<19 mm) Laminated < ½ in (<12 mm)

Very close ¾ in – 2-1/2 in (19 - 60 mm) Very thin ½ in – 2 in (12 – 50 mm)

Close 2-1/2 in – 8 in (60 – 200 mm) Thin 2 in – 1 ft. (50 – 300 mm)

Moderate 8 in – 2 ft. (200 – 600 mm) Medium 1 ft. – 3 ft. (300 – 900 mm)

Wide 2 ft. – 6 ft. (600 mm – 2.0 m) Thick 3 ft. – 10 ft. (900 mm – 3 m)

Very Wide 6 ft. – 20 ft. (2.0 – 6 m) Massive > 10 ft. (3 m)

Discontinuity Orientation (Angle): Measure the angle of discontinuity relative to a plane perpendicular to the longitudinal axis of the core. (For most cases, the core axis is vertical; therefore, the plane perpendicular to the core axis is horizontal.) For example, a horizontal bedding plane would have a 0-degree angle.

ROCK QUALITY DESIGNATION (RQD) 1

Description RQD Value (%)

Very Poor 0 - 25

Poor 25 – 50

Fair 50 – 75

Good 75 – 90

Excellent 90 - 100

1. The combined length of all sound and intact core segments equal to or greater than 4 inches in length, expressed as a percentage of the total core run length.

Reference: U.S. Department of Transportation, Federal Highway Administration, Publication No FHWA-NHI-10-034, December 2009 Technical Manual for Design and Construction of Road Tunnels – Civil Elements