Estrella-Wayside_Final_Geotechnical_Report_0002.pdf

Terracon Consul tants, Inc. | 4685 S. Ash Avenue, Ste. H-4 | Tempe, AZ | 85282 480-897-8200 | terracon.com

November 14, 2018

SEH, Inc.

503 North Main Street Pueblo, Colorado 81003

Attn: Mr. Jimmie Hayson Phone: 719-468-8373 Email: jhayson@sehinc.com

Re: Report of Expected Geotechnical Conditions BLM Recreation Plan for Butterfield, Estrella-Wayside, & Christmas Camp Juan Bautista de Anza Recreation Management Zone Sonoran Desert National Monument, Maricopa County, Arizona Terracon Project No. 65185188 Revision No. 1

Dear Mr. Hayson:

We are pleased to present this Report of Expected Geotechnical Conditions for the project referenced above. This study was performed in general accordance with our proposal number P65185188 dated August 3, 2018. This report includes:

n Exhibit A Project Information and Site Location n Exhibit B Scope of Services n Exhibit C n Exhibit D

Information Sources Confidence Estimate n Exhibit E n Exhibit F n Exhibit G n Exhibit H n Exhibit I n Exhibit J

Expected Subsurface Conditions Foundation, Slab, and Pavement Recommendations Earthwork Recommendations General Comments Site Location Map and Exploration Plans Laboratory Test Results

This report references a web-based, GIS portal that has been developed specific for this project using Terracon’s proprietary GIS platform providing you with dynamic access to the information compiled for this project. Access to this information can be gained by using this link:

https://portal.gis.terracon.com/Login/?project=SHE_65185188 mailto:jhayson@sehinc.com https://portal.gis.terracon.com/Login/?project=SHE_65185188

BLM Recreation Plan for Butterfield, Estrella-Wayside, & Christmas Camp Juan Bautista de Anza Recreation Management Zone ■ Sonoran Desert National Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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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.

Eddy F. Ramirez, P.E. Donald R. Clark, P.E.

Senior Staff Engineer Senior Principal

Attachments: Exhibit I-1 – Site Location Exhibit I-2 – Exploration Plan – Butterfield Exhibit I-3 – Exploration Plan – Estrella-Wayside Exhibit I-4 – Exploration Plan – Christmas Camp Exhibit J-1 – Atterberg Limits Results Exhibit J-2 and J-3 – Grain Size Distribution Exhibit J-4 – Summary of Laboratory Results

Copies to: Addressee (1 via email)

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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EXHIBIT A

PROJECT INFORMATION AND SITE LOCATION

Project Information

We understand the project includes improvements to three areas located in the Sonoran Desert National Monument as part of the Juan Bautista de Anza Recreation Management Zone. These three areas are designated as:

n the Butterfield Recreation Area;

n the Estrella-Wayside Recreation Areas; and, n the Christmas Camp Group Area.

The project sites are located approximately 11.7 miles to 21.8 miles east-northeast of Gila Bend, Arizona and are situated on the north side of Arizona State Route 238.

Our understanding of the project was developed based upon information provided by SEH, Inc..

The purpose of this project is to assess the surface and subsurface soil and rock conditions based on publicly available information regarding soils, geologic settings, topography, depth to groundwater and other site-specific data in conjunction with a review of Terracon’s historic geotechnical data in the area for use in rendering an opinion of the expected subsurface conditions anticipated for the proposed improvements to the three (3) recreational areas.

Item Description

Project Description

The Butterfield Recreation Area, the Estrella-Wayside Recreation Areas, and the Christmas Camp Group Area are planned to be improved in various phases. The planned improvements will ultimately include shade ramada structures, vault toilets, picnic tables, fire-rings, and gravel surfaced roads and parking areas.

Project Location

Recreational Areas Acreage Latitude Longitude Butterfield 450 33.005647° -112.529567°

Estrella-Wayside 2881 33.029327° -112.446133° Christmas Camp Group 584 33.049634° -112.355836°

Refer to the attached Site Location Map (Exhibit I-1).

Maximum Structure Loads (Assumed)

■ Columns: 1 kips

■ Walls: 1 kips per linear foot

■ Slabs: 150 pounds per square foot

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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Item Description

Pavements

On-site roadways, drives and parking areas for automobile and truck traffic are anticipated to consist of asphalt concrete, stabilized subgrade and/or gravel surfaced roads. No traffic information was provided; therefore, the assumed and anticipated traffic is as follows:

Autos/Light Trucks: 75 vehicles per day Trash Collection Vehicles: 5 vehicles per day

The pavement design period is 20 years

Site Location

Item Description

Location

The project is located at the Juan Bautista de Anza Recreation Management Zone in the Sonoran Desert National Monument, Maricopa County, Arizona.

See the Site Location Map (Exhibit I-1) for additional site location information.

Existing Improvements The proposed recreation sites are located in native desert land. There are some trails or graded dirt roads at each recreation area.

Current Ground Cover Generally native desert land with sparse vegetation.

Existing Topography Each proposed recreation area is located in relatively flat desert and are cut at certain intervals with some ephemeral washes. In addition, hills with some sloping ground are present in the vicinity of each site.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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EXHIBIT B

SCOPE OF SERVICES

REGC Desktop Review

This Report of Expected Geotechnical Conditions (REGC) provides an expectation of subsurface properties from a geotechnical engineering perspective. It is intended to assist in considering concepts for site development and provide preliminary foundation, slab and pavement recommendations for the project described in Exhibit A.

This REGC utilizes the following information:

■ Relevant, publicly-available, spatial data for use with GIS delivery platforms,

■ Terracon’s database of historic documents from geotechnical investigations conducted in the vicinity of the project site using our proprietary GIS-based information retrieval system.

This information is displayed on a proprietary, web-based map sequence developed for this project. The information can be accessed through this web page:

<https://portal.gis.terracon.com/Login/?project=SHE_65185188>

Limited Geotechnical Field Exploration

Terracon also performed a limited geotechnical field exploration at the site to evaluate the subsurface conditions and obtain representative shallow soil samples from each of the planned recreation areas. During the limited geotechnical field exploration, three subgrade samples were obtained at selected locations across the Butterfield Recreation Area, two subgrade samples were obtained at selected locations across the Estrella-Wayside Recreation Area, and, one subgrade samples was obtained at a selected location at the Christmas Camp Group Area. The samples were taken to our soil laboratory for testing and classification by a geotechnical engineer.

Laboratory Testing

General laboratory tests were conducted on the soil samples collected from the site and the test results are presented in Exhibit J (Exhibits J-1 through J-4). The soil samples obtained from the site were tested for the following engineering properties:

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■ ASTM D4318 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils

■ ASTM D422 Standard Test Method for Particle-Size Analysis of Soils

■ ASTM D516 Standard Test Method for Sulfate Ion in Water

■ ASTM G187 Standard Test Method for Measurement of Soil Resistivity Using the Two-

Electrode Soil Box Method

■ ASTM D4972 Standard Test Method for pH of Soils

■ ASTM D512 Standard Test Methods for Chloride Ion in Water

Laboratory tests were performed in general accordance with the applicable ASTM, local or other accepted standards.

A geotechnical engineer with local experience in the area of the planned project has formed an opinion of expected geotechnical conditions by reviewing the information as provided on the web page and our historic data in the vicinity of the project. The opinion rendered by the geotechnical engineer also includes an estimate of the confidence in that opinion.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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EXHIBIT C

INFORMATION SOURCES

Public Data Sources Reviewed

The web-map series that can be reviewed at the following link:

<https://portal.gis.terracon.com/Login/?project=SHE_65185188> includes the following sources of public information.

Category Source Topographic Overview USGS National Map web mapping service provided by ESRI Aerial Imagery Overview USDA FSA imagery provider, data source NAIP

USGS Geology USGS Preliminary Integrated Geologic Map Database for the United States

Karst Geology US Karst Areas web mapping service provided by ESRI Slope of Terrain USGS National Elevation Dataset provided by ESRI Soil and Surficial Materials

NRCS Soil Survey Geographic (SSURGO) Databases for the United States

Depth to Shallow Bedrock

NRCS Soil Survey Geographic (SSURGO) Databases for the United States

Depth to Shallow Water Table

NRCS Soil Survey Geographic (SSURGO) Databases for the United States

Soil Hydrologic Groups USGS Preliminary Integrated Geologic Map Database for the United States

Flooding Frequency NRCS Soil Survey Geographic (SSURGO) Databases for the United States

Terracon Historic Records in Project Vicinity

Our research of Terracon’s proprietary database of historic soil, groundwater and rock conditions in the vicinity of the site indicated six relevant projects within ten miles of the project site. The project locations are illustrated on the web-based map sequence.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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EXHIBIT D

CONFIDENCE ESTIMATE

The project geotechnical engineer has assigned confidence estimates for the data sets based upon the engineer's local practice in the vicinity of the sites. The results of this confidence ranking are presented in the chart below and is expressed as Low, Moderate or High. Using a weighted averaging approach, we derive an overall confidence interval for all of the combined information sources.

Low confidence implies that the level of data availability and/or consistency is such that little confidence can be placed in the Expected Geotechnical Conditions. Conversely, a high confidence ranking implies that sufficient data and consistency exists to derive a high confidence in the statement of expected conditions.

Regardless of the confidence ranking, the expected conditions must be confirmed with site-specific exploration data, and significant variations from the expected conditions are possible. The confidence ranking process is valuable in guiding the plan for construction of the project.

As the chart above illustrates, using our weighted average confidence estimator we have assigned a confidence estimate of “Moderate” for this project.

Using the publicly available data, Terracon’s proprietary database of soils information from projects near the proposed project, and our knowledge of general soil and bedrock conditions within the various geologic settings, we developed anticipated soil stratigraphy to a depth of 15 feet for the listed geologic settings at the project area.

0% 20% 40% 60% 80% 100%

PUBLIC DATA

LOCAL GEO EXPERIENCE

LOCAL EXPL. DATA

OVERALL CONFIDENCE RANK

Relative Confidence Estimate General

Confidence Estimate

Low

Moderate

Low

Moderate

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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EXHIBIT E

EXPECTED SUBSURFACE CONDITIONS

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 million years ago), the Basin and Range province is dominated by fault controlled topography. These mountain ranges and valleys have evolved from generally complex movements and associated erosional and depositional processes.

The geological units mapped at each of the recreation areas are outlined in the following table:

Recreation Area

Geological Unit

Symbol Geological Unit Geological Unit Description

Butterfield

Q Quaternary surficial deposits, undivided

(Quaternary)

This unit is described as unconsolidated to strongly consolidated alluvial and eolian deposits. This unit includes: coarse, poorly sorted alluvial fan and terrace deposits on middle and upper piedmonts and along large drainages; sand, silt and clay on alluvial plains and playas;

and wind-blown sand deposits. (0-2 Ma)

Xg Early Proterozoic Granitic Rocks

This unit is described as a wide variety of granitic rocks, including granite, granodiorite, tonalite, quartz diorite, diorite, and gabbro. These rocks commonly are characterized by steep, northeast-striking foliation. (1600- 1800 Ma)

Estrella- Wayside

Q Quaternary surficial deposits, undivided

(Quaternary)

This unit is described as unconsolidated to strongly consolidated alluvial and eolian deposits. This unit includes: coarse, poorly sorted alluvial fan and terrace deposits on middle and upper piedmonts and along large drainages; sand, silt and clay on alluvial plains and playas;

and wind-blown sand deposits. (0-2 Ma)

Xg Early Proterozoic Granitic Rocks

This unit is described as a wide variety of granitic rocks, including granite, granodiorite, tonalite, quartz diorite, diorite, and gabbro. These rocks commonly are characterized by steep, northeast-striking foliation. (1600- 1800 Ma)

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

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

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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Recreation Area

Geological Unit

Symbol Geological Unit Geological Unit Description

Christmas Camp Group Q

Quaternary surficial deposits, undivided

(Quaternary)

This unit is described as unconsolidated to strongly consolidated alluvial and eolian deposits. This unit includes: coarse, poorly sorted alluvial fan and terrace deposits on middle and upper piedmonts and along large drainages; sand, silt and clay on alluvial plains and playas;

and wind-blown sand deposits. (0-2 Ma)

Expected Subsurface Profile

Based on Terracon’s historical project data available in the vicinity of the sites from previous geotechnical site investigations and laboratory results from the samples obtained at the project site, subsurface conditions are expected to consist of the following general profile:

Depth

(feet) 1 Layer

Number Layer Description

(Consistency) Comments 2

5 to 8 I Silty Sand, Sandy Silt Loose to Medium Dense

5 to 15 II Silty Sand, Poorly Graded Sand Medium Dense to Very Dense

1. Estimated depth below ground surface.

2. The conditions described have been assigned a confidence level of moderate. See Exhibit D for details related to our estimate of confidence.

Corrosivity

Selected samples collected from the project site were tested for corrosivity to assist in determining the type and degree of corrosion protection that may be required. The following table lists the results of laboratory pH, electrical resistivity, soluble sulfate, and soluble chloride.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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Corrosivity Test Results Summary

Location Sample Depth (feet)

Soil Description pH Electrical Resistivity (Ω-cm)

Soluble Sulfate Content (ppm)

Soluble Chloride Content (ppm)

S-2 0 – 1 Silty Sand 8.7 6,450 5 6

S-4 0 – 1 Silty Sand 8.4 6,259 4 5

S-6 0 – 1 Silty Sand 8.5 4,315 2 5

Results of soluble sulfate testing indicate that samples of the on-site soils tested classify as S0 according to Table 19.3.1.1 of Section 318 of the American Concrete Institute (ACI) Building Code Requirements for Structural Concrete. Concrete should be designed in accordance with the provisions of the ACI Building Code Requirements for Structural Concrete, Section 318, Chapter 19.

Groundwater Conditions

Based on information obtained from the Arizona Department of Water Resources (ADWR) – Groundwater Data website (https://gisweb.azwater.gov/waterresourcedata/GWSI.aspx), the depth to regional groundwater within 1 mile of each recreation area is summarized in the following table:

Recreation Area

ADWR Monitored Well Site ID

Approximate Distance from Site

Depth to Regional Groundwater (ft.) Date Measured

Butterfield C-05-03 11ADC 300 feet north 503 November 1993

Estrella- Wayside C-04-01 32CDD 3 miles west 578 December 2017

Christmas Camp Group C-04-01 23CDB 1¼ miles west 503 June 2018 https://gisweb.azwater.gov/waterresourcedata/GWSI.aspx

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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Seismic Considerations

Design of structures subject to earthquake ground motions requires classification of the upper 100 feet of the site profile in accordance with Chapter 20 of ASCE 7-10. The Site Class types are listed below and are basically defined by an average value of either shear wave velocity, standard penetration resistance, or undrained shear strength.

n A. Hard Rock n B. Rock n C. Very dense soil and soft rock n D. Stiff soil n E. Soft clay soil n F. Soils vulnerable to potential failure or collapse under seismic loading

Based on the results of our site characterization program, we conclude that Site Class D is appropriate for the subject site. The following table provides the seismic design criteria in accordance with the 2012/2015 International Building Code at the approximate location of the site, obtained from the USGS Earthquake Hazards website:

Location Site

Class1

Site Latitude (ºNorth)

Site Longitude

(ºEast)

Ss - Spectral Acceleration for a Short

Period

S1 - Spectral Acceleration for a 1- Second Period

Fa - Site Coefficient for a Short

Period

Fv - Site Coefficient for a 1- Second Period

Butterfield D 33.0069 -112.5330 0.163g 0.056g 1.6 2.4 Estrella- Wayside D 33.0306 -112.4384 0.160g 0.055g 1.6 2.4

Christmas Camp Group D 33.0571 -112.3585 0.158g 0.054g 1.6 2.4

1 Note: In general accordance with the 2012/2015 International Building Code, Section 1613.3.2, which refers to Chapter 20 of ASCE 7-10. The procedure outlined in Chapter 20 of ASCE 7-10 relies on a site soil profile determination extending to a depth of 100 feet for seismic site classification. The current scope does not include the required 100-foot soil profile determination. The subsurface conditions were estimated based on our experience and knowledge of geologic conditions of the general area.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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EXHIBIT F

FOUNDATIONS, SLABS, AND PAVEMENTS RECOMMENDATIONS

Using the expected geotechnical conditions as noted above, and our understanding of the project as described in Exhibit A, we have developed recommendations for shallow foundations, interior floor slabs, and pavements for the proposed project.

Shallow Foundations

Recommendations for shallow foundations are provided in this report based on presumptive load bearing values published by the International Building Code (IBC) for lightly loaded small structures founded on native soils. Based on the expected geotechnical conditions at each of the recreation areas and Chapter 18 of the 2015 IBC, the following load-bearing values have been developed for shallow foundations that will support the planned structures.

Design Item Description/Recommendations Maximum Vertical Foundation

Pressure 1,2,3 2,000 psf

Minimum Embedment Depth Below finished grade 4 18 inches

Bearing Material Spread footings may be supported on undisturbed native soils or engineered fill (if required to raise site grades).

Minimum footing dimensions

Isolated Column Footings: 24 inches Continuous Wall Footings: 18 inches

1. The maximum net allowable bearing pressure is based on Table 1806.2 of the 2015 IBC.

2. The maximum net allowable bearing pressure is the pressure in excess of the minimum surrounding overburden pressure at the footing base elevation. The allowable bearing pressure may be increased by one-third when considering the alternative load combinations of Section 1605.3.2 of the 2015 International Building Code, however, it should not be increased when loads are determined by the basic allowable stress design load combinations of Section 1605.3.1.

3. Values provided are for maximum loads noted in Exhibit A.

4. Finished grade is defined as the lowest adjacent grade within 5 feet of the foundation for perimeter (or exterior) footings and finished floor level for interior footings.

Footings, foundations, and walls should be reinforced as necessary to reduce the potential for distress caused by differential foundation movement. The use of joints at openings or other discontinuities in walls is recommended.

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

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Lateral Earth Pressures

The presumptive lateral earth pressure recommendations herein are applicable to the design of footings and rigid retaining walls subject to slight rotation, such as cantilever, or gravity type concrete walls.

Design Parameter Design Value1

Active Case 40 psf/ft

Passive Case 330 psf/ft

At-Rest Case 55 psf/ft

Coefficient of Base Friction2 0.25 1 Note: The values are based on the on-site soils used as backfill.

2 Note: The coefficient of base friction is based on Table 1806.2 of the 2015 IBC.

The presumptive lateral earth pressures herein do not include any factor of safety, they assume drained conditions, they do not include surcharge loading, 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.

Fill against foundations and retaining walls should be compacted to densities specified in the Exhibit G. Compaction of each lift adjacent to walls should be accomplished with hand-operated tampers or other lightweight compactors.

Lateral Pressure for Light Pole Foundations

Based on Table 1806.2 of the 2015 IBC, a presumptive lateral bearing pressure of 150 psf/ft can be used for light pole foundations. Isolated light poles that are not adversely affected by a ½ -inch motion at the ground surface due to short-term lateral loads can be designed using lateral bearing pressure equal to two times the tabular values (300 psf/ft) shown in Table 1806.2 of the

2015 IBC.

Floor Slabs

Floor slabs (non-pavement areas) should be designed based on the following geotechnical recommendations:

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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Item Description Interior floor system Slab-on-grade concrete.

Floor slab support

A minimum of 10 inches of prepared subgrade soils, moisture conditioned and compacted in accordance the Exhibit G. Floor slabs should be supported on a minimum of 4 inches of ABC placed directly on the prepared subgrade soils.

Modulus of subgrade reaction1 200 pounds per square inch per inch (psi/in) for point loads

1. Modulus of subgrade reaction is an estimated value based upon our experience with the subgrade condition, the requirements noted in Exhibit G and the floor slab support as noted in this table.

Additional floor slab design and construction recommendations are as follows:

n Positive separations and/or isolation joints should be provided between slabs and all foundations, columns or utility lines to allow independent movement.

n Control joints should be provided in slabs to control the location and extent of cracking.

n Other design and construction considerations, as outlined in the ACI Design Manual, Section 302.1R are recommended.

n Some differential movement of a slab-on-grade floor system is possible on long-term settlement of the underlying materials. To reduce potential slab movements, the subgrade soils should be prepared as outlined in the Exhibit G.

Pavement Sections for Roadways and Parking Areas

We also understand the roadways and parking areas will be subjected to relatively light traffic and some limited amount of truck loading. Pavement designs are provided for the assumed and anticipated traffic conditions and pavement life conditions as noted in Exhibit A. A critical aspect of pavement performance is site preparation. The pavement designs noted in this section must be applied to the site that has been prepared as required in the Exhibit G section.

The pavement sections were designed using the American Association of State and Highway Transportation Officials (AASHTO) Guide for Design of Pavement Structures (1993) with selected modifications by the ADOT Pavement Design Manual, Chapter 2 New Pavement Design.

Development of layer thicknesses were determined using the layered elastic design methodology as outlined in the AASHTO 93 Design Guide, Part II, Section 3.1.5 Layered Design Analysis.

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Design Traffic Analysis: Traffic information for the proposed project was not provided. Therefore, the following traffic information for the proposed project was assumed for the pavement design analysis:

■ Average Daily Traffic of 75 automobiles and 5 trash collection trucks

■ The pavement design period is 20 years

The assumed and anticipated traffic levels were converted into 18-kip equivalent single axle loads (ESALs) for use in the thickness designs of asphalt concrete (AC), gravel surfaced roads, and cement treated subgrade pavements as noted in the following table. Our office should be contacted if there are any changes in the anticipated or actual traffic patterns or frequency to review the design values.

Anticipated Traffic1,2 Average Daily Traffic1 Equivalent Single 18-kip Axle

Loads (ESAL’s) 2

Automobiles and Light Truck 75 4,392

Trash Collection Trucks 5 35,040

Total --- 39,432

1. Assumed traffic conditions.

2. 20-year design life.

Pavement Subgrade Parameters: The design resilient modulus (MR) for the pavement analyses was determined in accordance with the procedures of the ADOT Preliminary Engineering and Design Manual. The methodology uses data from R-value data correlated with sieve and plasticity index results. The results of the laboratory testing including the correlated R-Values are summarized in the following table:

SUMMARY OF CORRELATED R-VALUES

Boring No. Depth LL PI -#200 R-Value Correlated

S-1 0 – 1 --- NP 29 67

S-2 0 – 1 --- NP 37 60

S-3 0 – 1 --- NP 31 65

S-4 0 – 1 --- NP 44 54

S-5 0 – 1 --- NP 51 49

S-6 0 – 1 --- NP 32 64

Number of Tests 6 Correlated Rmean

Average 60.05

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SUMMARY OF CORRELATED R-VALUES

Boring No. Depth LL PI -#200 R-Value Correlated

Standard Deviation 6.87

Seasonal Variation Factor 1.0

Design Resilient Modulus

26,000 psi (maximum allowed by design procedures)

The calculated mean correlated R-value determined from the analyses is 60.05. A Seasonal Variation Factor (SVF) of 1.0 was assigned for the project based on Table 2-4 of the ADOT Pavement Design Manual. The manual provides SVF values for nearby locations with similar elevations. The RMEAN value, combined with a Seasonal Variation Factor of 1.0 results in the maximum resilient modulus (MR) of 26,000 psi, the maximum allowed by design procedures.

Pavement Design Parameters: Analyses for the pavement design for the project has been based on the procedures of AASHTO with selected modifications by the Arizona Department of Transportation. The following design parameters, as determined by the procedures outlined in the ADOT Pavement Design Manual, were utilized for pavement engineering analyses and the determination of design alternatives for the project:

Pavement Design Parameters

Reliability Level of Reliability 85%

Overall Standard Deviation 0.45

Serviceability Initial PSI 4.1

Terminal PSI 2.6

Subgrade Conditions

Rmean 60.05

Correlated Resilient Modulus 26,000 psi

Seasonal Variation Factor 1.0

Layer Properties

Asphalt Concrete (AC) Layer Coefficient 0.44 Aggregate Base (ABC) Layer Coefficient 0.14

Cement Treated Subgrade Layer Coefficient 0.23 Aggregate Base (ABC) Drainage Coefficient 1.0

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Pavement Section Thickness: Based on the results of the analyses, recommended design alternatives are summarized as follows:

Alternative Recommended Pavement Section Thickness (inches)

Asphalt Concrete

Aggregate Base Course

Cement Treated Subgrade Total

A 2.5 4.0 --- 6.5

B --- 8.0 --- 8.0

C -- --- 6.01 6.0

1. Placement of a chip seal should be completed on top of the cement treated subgrade. See the discussion below about the performance characteristics of a soil–cement pavement.

These pavement sections are considered minimal sections based upon the assumed and anticipated traffic and the existing subgrade conditions. However, they are expected to function with periodic maintenance if good drainage is provided and maintained.

To provide some level of protection of the soil-cement from water intrusion into cracks, and to provide a wearing surface for traffic, placement of a chip seal should be completed as soon as practical after the soil-cement has been allowed to properly cure. An asphalt-rubber chip seal would provide better resilience to shrinkage cracks that could develop in the surface of the soil-cement. The design and construction of cement treated subgrade should be performed in general accordance with the requirements and specifications in Section 311 of the Maricopa Association of Governments (3MAG, 2018). The resultant minimum compressive strength of soil-cement using the on-site subgrade materials should be a minimum of 800 psi at 7 days of age (under soaked conditions).

Each of the pavement alternatives outlined above should be investigated with respect to current material availability, economic conditions, future maintenance issues, and management factors when selecting the final alternative for the project.

Pavement Specifications and Maintenance: Materials and construction of pavements for the project should be in accordance with the requirements and specifications of the Maricopa Association of Governments (4MAG, 2018). Base course or pavement materials should not be

3 Maricopa Association of Governments, 2018, Uniform Standard Specifications and Details for Public Works Construction, Arizona.

4 Maricopa Association of Governments, 2018, Uniform Standard Specifications and Details for Public Works Construction, Arizona.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

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A concern regarding the use of permeable aggregate materials or cement treated subgrade in large roadway or parking areas is that surface water cannot be drained over the surface before it permeates through the aggregate surfacing, which would create a condition where the subgrade soils become wet. If the subgrade soils do become elevated in moisture content, the overall performance of the aggregate surfaced roadway and parking areas will be reduced and could result in excessive rutting or deterioration. To help direct surface water over the aggregate or cemented treated subgrade surface, we suggest surface slopes of 2% to 3% be constructed and maintained.

Surface drainage should be directed away from the pavement areas, and no ponding of water should be allowed on the paved surface or adjacent to the edges of the pavement areas.

Preventative maintenance should be planned and provided for through an on-going pavement management program to enhance future pavement performance. Preventative maintenance activities are intended to slow the rate of pavement deterioration, and to preserve the pavement investment.

Preventative maintenance consists of both localized maintenance (e.g. crack sealing and patching) and global maintenance (e.g. surface sealing). Preventative maintenance is usually the first priority when implementing a planned pavement maintenance program and provides the highest return on investment for pavements.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

Responsive ■ Resourceful ■ Reliable Exhibit G

EXHIBIT G

PRELIMINARY EARTHWORK RECOMMENDATIONS

The following presents preliminary recommendations for site preparation, excavation, subgrade preparation, and placement of engineered fills on the project.

Site Preparation

Strip and remove all vegetation and any deleterious materials from all proposed structure, roadway and parking areas. Exposed surfaces should be free of mounds and depressions which could prevent uniform compaction. The site should be initially graded to create a relatively flat surface to receive fill, and to provide for a relatively uniform thickness of fill beneath proposed structures.

Subgrade Preparation

Subgrade soils beneath planned construction areas should be scarified, moisture conditioned and compacted to a minimum depth of 10 inches. The moisture content and compaction of subgrade soils should be maintained until slab or pavement construction.

Subgrade soils beneath soil-cement pavement areas (if used), should be scarified, moisture conditioned and compacted to a minimum depth of 10 inches prior to proceeding with mixing.

Fill Material Types

All fill materials should be inorganic soils free of vegetation, demolition debris, and fragments larger than four inches in size. Clean on-site soils or approved imported materials may be used as fill material for the following:

Fill Type 1 USCS Classification Acceptable Location for Placement

On-Site Soils SM, ML The on-site silty sand and sandy silt soils are considered suitable for use as engineered fill at all locations and elevations.

Imported Material Varies All locations and elevations

1. Controlled, compacted fill should consist of approved materials that are free of organic matter, debris, and oversized materials. A sample of each material type should be submitted to the geotechnical engineer for evaluation.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

Responsive ■ Resourceful ■ Reliable Exhibit G

Imported soils (if required) should conform to low volume change materials as indicated in the following specifications:

Percent Finer by Weight Gradation (ASTM C136)

4" No. 4 Sieve ..................................................................................... 50-100 No. 200 Sieve ............................................................ 15 (min) to 45 (max) n Liquid Limit ....................................................................... 30 (max) n Plasticity Index ................................................................. 10 (max) n Maximum expansive potential (%)* ............................................ 1.5

*Measured on a sample compacted to approximately 95 percent of the ASTM D698 maximum dry density at about 3 percent below optimum water content. The sample is confined under a 100 psf surcharge and submerged/inundated.

Aggregate base course should conform to the Maricopa Association of Governments (MAG) specifications.

Fill Compaction Requirements

Engineered fill should meet the following compaction and moisture requirements:

Material Type and Location

Per the Standard Proctor Test (ASTM D 698)

Compaction Requirement

Range of Moisture Contents for Compaction (referenced from optimum moisture content) Minimum Maximum

On-site and imported soils beneath foundations, floor slabs, and pavements: 95 -2% +3%

Aggregate base (beneath concrete slabs) 95 -2% +3%

Aggregate base (beneath asphalt pavements) 100 -2% +3%

Aggregate surfaced pavements and soil-cement 95 -2% +3%

Miscellaneous backfill 95 -2% +3%

1. The moisture content and compaction should be measured for each lift of engineered fill during placement.

Should the results of the in-place density tests indicate the specified moisture or compaction limits have not been met, the area represented by the test should be reworked and retested as required until the specified moisture and compaction requirements are achieved.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

Responsive ■ Resourceful ■ Reliable Exhibit H

EXHIBIT H

GENERAL COMMENTS

The data and opinions provided in this report are estimates of geotechnical parameters. They have been derived based on review of the data outlined in this report and without the benefit of subsurface exploration at the location of planned structures. Any opinions regarding the subsurface conditions for this project may not represent actual conditions encountered during project exploration or construction. Therefore, confirmation of the opinions stated in this document is essential. At a minimum, confirmation should include engineering observations of all excavations made for planned foundations to support structures on this project, field and laboratory testing of engineered fill soils placed on the project, materials testing during roadway and parking area construction, and when necessary, supplementary geotechnical exploration of the site at planned construction areas.

The scope of services for this project addresses preliminary geotechnical conditions only. The scope does not include either specifically or by implication any environmental assessment of the site or identification or prevention of pollutants, hazardous materials or conditions.

This report has been prepared for the exclusive use of SEH, Inc. to represent preliminary opinions of geotechnical conditions for specific application to the project described in Exhibit A and in accordance with generally accepted geotechnical engineering practices. No warranties, either express or implied, are intended or made.

In the event that changes in the nature, design, or location of the project as outlined in this report are planned, the preliminary conclusions and recommendations contained in this report shall not be considered valid unless Terracon reviews the changes and either verifies or modifies the conclusions of this report in writing.

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.

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

Responsive ■ Resourceful ■ Reliable Exhibit H

EXHIBIT I

SITE LOCATION MAP AND EXPLORATION PLANS

Estrella-Wayside

Recreation Area

Butterfield

Recreation Area

Christmas Camp

Group Area

TOPOGRAPHIC MAP IMAGE COURTESY OF

THE U.S. GEOLOGICAL SURVEY

QUADRANGLES INCLUDE: BUTTERFIELD

PASS, AZ (1/1/1973) and ESTRELLA, AZ (1/1/1979).

SITE LOCATION

BLM Recreation Plan for Butterfield, Estrella-Wayside, & Christmas Camp Juan Bautista de Anza Recreation Management Zone

Sonoran Desert National Monument Maricopa County, Arizona

4685 S Ash Ave, Ste H-4

Tempe, AZ 85282-6767

65185188

DIAGRAM IS FOR GENERAL LOCATION ONLY,

AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

Project Manager:

Drawn by:

Checked by:

Approved by:

EFR

EFR

DRC

EFR

Exhibit I

11/14/18

Project No.

File Name:

Date:

I-1

Exhibit

1”=2,000’ Scale:

TOPOGRAPHIC MAP IMAGE COURTESY OF

THE U.S. GEOLOGICAL SURVEY

QUADRANGLES INCLUDE: BUTTERFIELD

PASS, AZ (1/1/1973) and ESTRELLA, AZ (1/1/1979).

EXPLORATION PLAN - BUTTERFIELD

BLM Recreation Plan for Butterfield, Estrella-Wayside, & Christmas Camp Juan Bautista de Anza Recreation Management Zone

Sonoran Desert National Monument Maricopa County, Arizona

4685 S Ash Ave, Ste H-4

Tempe, AZ 85282-6767

65185188

DIAGRAM IS FOR GENERAL LOCATION ONLY,

AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

Project Manager:

Drawn by:

Checked by:

Approved by:

EFR

EFR

DRC

EFR

Exhibit I-2

10/18/18

Project No.

File Name:

Date:

I-2

Exhibit

QUADRANGLES INCLUDE: BUTTERFIELD

PASS, AZ (1/1/1973) and ESTRELLA, AZ

EXPLORATION PLAN - ESTRELLA-WAYSIDE

Sonoran Desert National Monument Maricopa County, Arizona

4685 S Ash Ave, Ste H-4

Tempe, AZ 85282-6767

65185188

DIAGRAM IS FOR GENERAL LOCATION ONLY,

AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

Project Manager:

Drawn by:

Checked by:

Approved by:

EFR

EFR

DRC

EFR

Exhibit I-3

10/18/18

Project No.

File Name:

Date:

I-3

Exhibit

QUADRANGLES INCLUDE: BUTTERFIELD

PASS, AZ (1/1/1973) and ESTRELLA, AZ

EXPLORATION PLAN - CHRISTMAS CAMP

Sonoran Desert National Monument Maricopa County, Arizona

4685 S Ash Ave, Ste H-4

Tempe, AZ 85282-6767

65185188

DIAGRAM IS FOR GENERAL LOCATION ONLY,

AND IS NOT INTENDED FOR CONSTRUCTION

PURPOSES

Project Manager:

Drawn by:

Checked by:

Approved by:

EFR

EFR

DRC

EFR

Exhibit I-4

10/18/18

Project No.

File Name:

Date:

I-4

Exhibit

Monument, Maricopa County, Arizona November 14, 2018 ■ Terracon Project No. 65185188 Revision No. 1

Responsive ■ Resourceful ■ Reliable Exhibit H

EXHIBIT J

LABORATORY TEST RESULTS

0 20 40 60 80 100

"U " L ine

"A " L ine

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

LL USCS

S-1

S-2

S-3

S-4

S-5

S-6

ATTERBERG LIMITS RESULTS

ASTM D4318

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

CH

o r

OH

CL

o r

OL

ML or OL

MH or OH

PL PIBoring ID Depth Description

SILTY SAND

SILTY SAND

SILTY SAND

SILTY SAND

SANDY SILT

SILTY SAND

SM

SM

SM

SM

ML

SM

Fines

P L A S T I C I T Y

I N D E X

LIQUID LIMIT

PROJECT NUMBER: 65185188

PROJECT: Proposed BLM Recreation Areas

SITE: Multiple Locations Maricopa, AZ

CLIENT: SEH, Inc.

Pueblo, CO

EXHIBIT: J-1

4685 S Ash Ave Ste H-4

Tempe, AZ

LA

B

O R

A T

O R

Y T

E S

T S

A R

E N

O T

V A

LI

D

IF

S

E P

A R

A T

E D

F R

O M

O R

IG

IN

A L

R E

P O

R T

A

T E

R B

E R

G L

IM

IT

S

P R

O P

O S

E D

B

LM

R E

C R

.G P

J T

E R

R A

C O

N

.G

D

/2 /1

8 CL-ML

0.0010.010.1110100

S-1

S-2

S-3

S-4

S-5

NP

NP

NP

NP

NP

0.0790.837

0.36

0.61

0.145

0.115

31.5

6 16 20 30 40 501.5 2006 810

8.2

7.8

6.1

5.6

4.0

LL PL PI

41 3/4 1/2 60 fine

S-1

S-2

S-3

S-4

S-5

GRAIN SIZE IN MILLIMETERS

P E

R C

E N

T F

IN

E

R B

Y W

E

IG

H T coarse fine

HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS

NP

NP

NP

NP

NP

NP

NP

NP

NP

NP

D100

Cc Cu

SILT OR CLAY

%Sand%GravelD30 D10

3/8 3 100 1403 2

COBBLES

GRAVEL SAND

62.8

55.2

62.6

49.9

45.1

D60 coarse medium

Boring ID Depth

Boring ID Depth

GRAIN SIZE DISTRIBUTION

ASTM D422 / ASTM C136

WC (%)USCS Classification

SILTY SAND (SM)

SILTY SAND (SM)

SILTY SAND (SM)

SILTY SAND (SM)

SANDY SILT (ML)

%Fines%Silt

29.0

37.1

31.2

44.5

50.9

%Clay

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

0 - 1

PROJECT NUMBER: 65185188

PROJECT: Proposed BLM Recreation Areas

SITE: Multiple Locations Maricopa, AZ

CLIENT: SEH, Inc.

Pueblo, CO

EXHIBIT: J-2

4685 S Ash Ave Ste H-4

Tempe, AZ

LA

B

O R

A T

O R

Y T

E S

T S

A R

E N

O T

V A

LI

D

IF

S

E P

A R

A T

E D

F R

O M

O R

IG

IN

A L

R E

P O

R

G R

A

IN

S

IZ

E : U

S C

S -2

P

R O

P O

S E

D B

LM

R

E C

R .G

P J

T E

R R

A C

O N

.G

0.0010.010.1110100

S-6 NP

0.60525

6 16 20 30 40 501.5 2006 810

6.1

LL PL PI

41 3/4 1/2 60 fine

S-6

GRAIN SIZE IN MILLIMETERS

P E

R C

E N

T F

IN

E

R B

Y W

E

IG

H T coarse fine

HYDROMETERU.S. SIEVE OPENING IN INCHES U.S. SIEVE NUMBERS

NP NP

D100

Cc Cu

SILT OR CLAY

%Sand%GravelD30 D10

3/8 3 100 1403 2

COBBLES

GRAVEL SAND

61.7

D60 coarse medium

Boring ID Depth

Boring ID Depth

GRAIN SIZE DISTRIBUTION

ASTM D422 / ASTM C136

WC (%)USCS Classification

SILTY SAND (SM)

%Fines%Silt

32.2

%Clay

0 - 1

0 - 1

PROJECT NUMBER: 65185188

PROJECT: Proposed BLM Recreation Areas

SITE: Multiple Locations Maricopa, AZ

CLIENT: SEH, Inc.

Pueblo, CO

EXHIBIT: J-3

4685 S Ash Ave Ste H-4

Tempe, AZ

LA

B

O R

A T

O R

Y T

E S

T S

A R

E N

O T

V A

LI

D

IF

S

E P

A R

A T

E D

F R

O M

O R

IG

IN

A L

R E

P O

R

G R

A

IN

S

IZ

E : U

S C

S -2

P

R O

P O

S E

D B

LM

R

E C

R .G

P J

T E

R R

A C

O N

.G

S-1 0.0 - 1.0 SM 29 NP NP NP

S-2 0.0 - 1.0 SM 37 NP NP NP 8.7 6450 5 6

S-3 0.0 - 1.0 SM 31 NP NP NP

S-4 0.0 - 1.0 SM 44 NP NP NP 8.4 6259 4 5

S-5 0.0 - 1.0 ML 51 NP NP NP

S-6 0.0 - 1.0 SM 32 NP NP NP 8.5 4315 2 5

pH Resistivity

(ohm-cm) Sulfates (ppm)

Chlorides (ppm)

Dry Density

(pcf)

Expansion

Corrosivity

Dry Density (pcf)

Atterberg Limits

In-Situ Properties

Passing #200

Sieve (%)

Classification

PL PI

Water Content

Remarks

Expansion Testing

Surcharge (psf)

Water Content (%) LL

USCS

Soil

Class.

Expansion

Index

EI

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.)

SUMMARY OF LABORATORY RESULTS

PROJECT: Proposed BLM Recreation Areas PROJECT NUMBER: 65185188

CLIENT: SEH, Inc.

Pueblo, CO

SITE: Multiple Locations Maricopa, AZ

PH. 480-897-8200 FAX. 480-897-1133

4685 S Ash Ave Ste H-4 Tempe, AZ

EXHIBIT: J-4

T H

IS

B

O R

IN

G

L O

G

IS

N O

T V

A

LI

D

IF

S E

P A

R A

T E

D F

R O

M O

R

IG

IN

A

L R

E P

O R

S

O

IL

P R

O P

E R

T

IE

S

P

R O

P O

S E

D B

LM

R

E C

R .G

P J

T E

R R

A C

O N

.G D

T

/2