ULTF_Geotechnical Design Report Rev 2_Volume 1.pdf

Underwater Launch Test Facility Crane Naval Base - Crane, Indiana

Geotechnical Design Report

February 28, 2020

Geotec hnical D esign Rep ort Client

Geotechnical Design Report

Crane, Indiana i

Underwater Launch Test Facility

Project No: FDWD3710 Document Title: Geotechnical Design Report Revision: 2 Date: February 28, 2020 Client Name: NAVFAC Project Manager: Karl Manger Author: Shane Rasch P.E., Nicholas J. Roth P.E., Anthony Stein

Jacobs

One Financial Plaza 501 North Broadway St. Louis, Missouri 63102 United States T +1.314.335.4000 F +1.314.335.5104 F + 1.314.335.5141 www.jacobs.com

© Copyright 2019 Jacobs. The concepts and information contained in this document are the property of Jacobs. Use or copying of this document in whole or in part without the written permission of Jacobs constitutes an infringement of copyright.

Limitation: This document has been prepared on behalf of, and for the exclusive use of Jacobs’ client, and is subject to, and issued in accordance with, the provisions of the contract between Jacobs and the client. Jacobs accepts no liability or responsibility whatsoever for, or in respect of, any use of, or reliance upon, this document by any third party.

Document history and status

Revision Date Description By Review Approved

1 10/4/2019 Progression to 60% Design AMS NR SMR

2 2/25/2020 Progression to 95% Design AMS SMR NJR rothn Image

Crane, Indiana ii

Contents

1. Introduction

2. Scope of Work Summary

3. Site Description

4. Historical Document Review

5. Regional Geological Setting

5.1 Seismic Zone

6. Subsurface Conditions

6.1 Borings & Test Pits

6.2 Test Pits & Bulk Sampling

6.3 Geophysical Testing

6.4 Water Level Measurements and Piezometers

6.5 Packer Testing

6.6 Infiltration/Percolation Testing

7. Evaluation & Commentary

7.1 Shear Strengths and Compressibility of Soils

7.2 Shallow Rock

7.3 Groundwater

7.4 Compaction

7.5 Equipment Mobility

8. Geotechnical Recommendations

8.1 Above Grade Structural Foundations

8.2 Frost

8.3 Seismic Design Parameters

8.4 Floor Slabs

8.5 Crane Pad

8.6 Laydown Pad

8.7 General Retaining Walls & Lateral Earth Pressures

8.8 Dynamic Response of Yielding Retaining Walls

8.9 Dynamic Response of Non-Yielding Walls

8.10 Retaining Wall Global Stability

8.11 Launch Pit

8.12 Earthwork

8.13 Subsurface Utilities

8.14 Fill Slopes

8.15 Site Excavations

8.16 Corrosion Potential

8.17 Radon

8.18 Pavement

9. Geotechnical Risk

10. Report Limitations

11. References

Appendix A. Boring Location Plan Appendix B. Boring Logs Appendix C. Fence Profiles Appendix D. General Notes Appendix E. Terracon Geophysical Report dated May 10, 2019 Appendix F. Terracon Data Summary Report, dated September 3, 2019 Appendix G. Seismic Design Maps

Crane, Indiana iii

Appendix H. SLIDE Output Appendix I. Launch Test Pit Calculations Appendix J. Foundation Calculations Appendix K. Crane Pad and Laydown Area Calculations Appendix L. Pavement Values & Pavement Calculations

Crane, Indiana iv

Executive Summary The proposed project is an Underwater Launch Test Facility (ULTF) at the Naval Surface Warfare Center (NSWC) in Crane, Indiana. The project includes a large below grade pit filled with water, a series of four one-story support structures, a crane pad, a laydown area, two above-grade retaining walls, two detention ponds and a series of new roads including a paved road accessing the site to the north. The electric substation will be constructed on the southwest corner of the site. The site is located on top of a ridge with slopes extending downward to the north and south.

The site is underlain by approximately 10 feet of overburden soil generally consisting of low to medium plasticity materials that are relatively firm to very stiff. The bedrock in the area generally consists of interbedded layers of sandstone and shale. The groundwater table is estimated to be 50 to 60 feet below the existing grade with a perched water level near the soil-rock interface.

Based on the geotechnical and project information available, Jacobs has identified five geotechnical items that will control the behavior of the proposed structures and will impact the proposed development:

1. The shear strength and compressibility of the upper soils will control the behavior of the proposed grade supported structures.

2. Relatively shallow rock (<10 feet) was encountered that will impact the excavation for the proposed launch pit and may impact construction of the above grade structures and utilities.

3. Ground water may be present within the limits of deep utility and foundation excavations that may require dewatering or alternative construction methods.

4. Drying of some of the on-site soils may be required to achieve proper compaction during grading. Amendment of the underlying soils should be anticipated during wetter periods of the year.

5. Relatively sensitive soils were encountered in the upper parts of the borings that may present mobility challenges with conventional equipment.

The following are notable geotechnical findings and commentary on the development of the site:

· The launch pit will be constructed as a slurry wall system extending to an elevation of 575 feet (approximately 145 feet below existing ground surface). A series of tieback anchors will need to be installed during pit excavation ranging in lengths from 30 to 45-foot long, with bond zones ranging from 20 to 35-foot long.

· The proposed one-story structures can be supported on conventional spread-type footing foundations bearing on either competent naturally deposited soil or compacted-engineered fill with allowable soil bearing pressures of 2,500 psf (continuous) to 3,000 psf (columns).

· Due to the close proximately of rock and the shear wave velocity profile of the subsurface material, the site is classified as a Seismic Site Class B. Based on a Seismic Risk Category II, a Seismic Design Category of B can be used for design.

· Floor slabs are anticipated to be able to be supported by the on-site materials; however, some additional crushed stone may be needed for heavier loads.

· Due to the anticipated loads, the crane pad will need to be excavated to rock and backfilled with a geogrid reinforced densely graded stone. The contractor layout/staging area, located on the western boundary of the site, is anticipated to consist of 24 inches of densely graded aggregate underlain by a geotextile.

· The infiltration rates of surficial soils and underlying bedrock are relatively low and should not be relied on in design of the detention pond outlets.

· Based on traffic loadings based on anticipated forklift traffic for rigid and flexible pavements, sections of 15 inches and 22 inches, respectively, should be anticipated.

The above information is a summary of the geotechnical exploration, evaluation and recommendations for the project. This report should be read in its entirety and this summary should not be relied on solely for design.

Crane, Indiana

1. Introduction The Naval Facilities Engineering Command (NAVFAC) has contracted Jacobs to design a new Underwater Launch Test Facility (ULTF) at the Naval Surface Warfare Center (NSWC) in Crane, Indiana. The primary components of the project are an underwater launch deep pit, an associated test vehicle catchment, an Operations Support Building, a Filtration Plant, a Warehouse and various site utility structures. A rehabilitation of the existing Highway 486 is proposed that includes paving the existing gravel road from Highway 331 south to the south side of the project site.

The launch pit is proposed to be an approximately 72-foot by 157-foot rectangular, approximately 121-foot deep, concrete-lined pit that houses and/or provides support for launch test equipment and the test article. The pit will be filled with water to varying heights above the top of the test article during the tests. The lining for the pit is anticipated to consist of slurry wall panels and a series of soil/rock anchor tiebacks. The above grade structures are anticipated to be metal framed structures supported on spread footings with grade-supported slabs.

Table 1 – Design Information Basis

Structural Minimum/Maximum Column Loads 15 kips to 80 kips Maximum Continuous Wall Loads Less than 1 kip per foot Equipment Loads LTV Cart: 260-kip Total, 32.5 kip per each of 8 wheels LTV Cradle: 260-kip Total, 130 kip per each of 2 cradles Gantry crane: 40.2-kip Total, 10.1 kip per each of 4 wheels H210HD Forklift: 46.7-kip Total, 23.4 kip per each of 2 wheels H60FT Forklift: 14.2-kip Total, 7.1 kip per each of 2 wheels E45Z Forklift: 12.3-kip Total, 6.15 kip per each of 2 wheels Storage Rack Post: 8 kips

Substation Loads Maximum Load: 150 kips Building Slab Loads Office Area: 100 psf

Instrument/Control Areas: 150 psf Pallet Storage Areas: 250 psf

Settlement Tolerances 1-inch total ½-inch differential between adjacent columns ½-inch differential in 30 feet for continuous footings

Building Code Unified Facilities Criteria (UFC) | WBDG - Whole Building Design Guide 2018 International Building Code (IBC)

IBC Risk Category Category II Civil Finished Floor Elevation/Grading Top of Pit ~ Elevation 719 feet

General Structures ~ Elevation 715 feet Launch Pit 72-foot wide by 157-foot long (~3-foot wide)

Top of Pit Elevation: 719 feet Bottom of Pool Elevation: 598 feet Base of Excavation: 582 feet Bottom of Slurry Wall: 575 feet

Below-grade Utilities 0 to -8 feet of existing grade Traffic Loading Hyster 210HD2, 10-ton capacity

23.4-kip forklift (passenger vehicles based on 137,000 Rigid and 89,000 Flexible ESALs)

Crane, Indiana

If variations to the above information are required, the geotechnical engineer should be given the opportunity to review the recommendations herein and revise as needed.

2. Scope of Work Summary The purpose of this report is to document the geotechnical study performed at the project site located at the Naval Surface Warfare Center (NSWC) in Crane, Indiana and provide engineering recommendations for the proposed development. Jacobs subcontracted Terracon to perform the geotechnical exploration, geophysical and laboratory testing for the project under our supervision. Our scope of work included drilling 19 conventional borings to depths between 30 feet (or refusal) and 200 feet, digging two test pits, installing two piezometers to depths between 10 feet and 200 feet, conducting two infiltration tests, and geophysical testing. An additional 11 borings were completed to the north of the site, along Highway 486. This report outlines the available project information, describes the site and subsurface conditions of the site, and includes recommendations for the following items:

· Anticipated settlements, differential settlements, construction methods and construction problems associated with proposed foundation systems.

· Subgrade modulus values for slab design.

· Lateral earth pressures and recommendations for the design of braced foundations, below-grade walls and water line thrust blocks.

· Anticipation of and management of groundwater and surface water both during construction and for the usable life of the completed project.

· Material and compaction requirements for support of structures, slab-on-grade and for backfill.

· Evaluation of suitability of site soil as building and pavement subgrade and as backfill.

· Subbase and pavement designs, both rigid and flexible. Provide appropriate pavement designs according to local statutory requirements, materials and practice.

· Design criteria for excavation, and temporary earth retention systems in accordance with OSHA

Standards.

· Seismicity of the project site, including appropriate design level and soil coefficients.

· Evaluation and recommendations for retaining walls including the launch pit and above-grade retaining walls.

· Frost penetration depth and effect.

· Recommendations for support of the proposed crawler crane pad and laydown area pad.

3. Site Description The project lies in Martin County, Indiana. The proposed site is located roughly one-half mile north-by-northeast of Greenwood Lake Dam on a small plateau along Highway 486, standing between 110 and 140 feet above the crest of the Dam (Figure 1). The average slope of the ground between the site and Greenwood Lake is 13%. The site is generally flat latitudinally, with local slopes of no more than 1-2%, and has a slight crest longitudinally. Just north of the site, the ground slopes down towards a small creek which feeds Oberlin Lake located to the southwest. The average ground slope between the site and the creek feeding Oberlin Lake is generally equal to that between the site and Greenwood Lake.

ULTF

Site

Figure 1 – Project Site (GoogleEarth)

Crane, Indiana

4. Historical Document Review Historical Aerial photo imagery from 1990 through March 2018 was reviewed using Google™ Earth. Based upon the review, the site was relatively static between 1998 and 2019 consisting predominantly of dense wooded areas.

Some minor clearing was noted towards the north end of Highway 486 near its intersection with Highway 331 in 2002 (Figure 2 and Figure 3).

Figure 2 – 1998 Historical Image (GoogleEarth) Figure 3 – 2002 Historical Image (GoogleEarth)

5. Regional Geological Setting The project site is located within the Crawford Upland of the Interior Low Plateau Physiographic Province.

The Crawford Upland is characterized by gently to moderately sloping ridges that are separated by steep to very steep valleys. The general structural geologic setting in Indiana consists of a broad anticline with a slight plunge to the northwest and is located east of the Illinois Basin. Pennsylvanian and Mississippian-aged bedrock commonly outcrops within Martin County.

The project site is slightly west of the Pennsylvanian- Mississippian contact. Shown by Figure 4 is the general bedrock geology of Indiana with the project site indicated (Okonkwo 1986).

The predominant Pennsylvanian unit in the county, the Mansfield Formation of the Raccoon Creek Group, consists primarily of sandstone, with quarzitic, cherty conglomerate interbeds and carbonaceous shale, and has a thickness between 50 feet and 300 feet (15 to 91m). The youngest Mississippian group in the county, in direct contact with the Mansfield Formation, is the Buffalo Wallow group. The Buffalo Wallow group consists mostly of shale and mudstone, contains thick interbeds of sandstone and limestone, and has a thickness between 270 feet and 675 feet (82 to 208 m) (Herring 2003).

Figure 4 – Indiana Bedrock Geology (Indiana Geological and Water Survey, 2018)

Crane, Indiana

Figure 5 below shows the major aquifer systems in the area as well as the known underground mines. The recorded known surface mines in the county are shown by Figure 6. Neither high flow aquifers nor underground mines are expected near the project site.

Figure 5 – Aquifer Map (IDNR) Figure 6 – Surface Mine Map (GoogleEarth)

5.1 Seismic Zone

The proposed site is within the eastern periphery of the Wabash Valley Seismic Zone and is roughly 180 miles (290km) northeast of the New Madrid Seismic Zone. The Wabash Valley Seismic Zone has produced several earthquakes between 4.5 and 5.5 on the Richter scale in the past 35 years, and commonly produces quakes of magnitude 3.5 and lower, though these are not usually felt. Steven Obermeir (USGS) and others have found evidence indicating the Wabash Valley Seismic Zone can produce magnitude 7.0 quakes, with a recurrence interval in the thousands of years. The New Madrid Seismic Zone has produced several large earthquakes in the past several hundred years, the most famous of which was a series of quakes between December 1811 and March 1812. At least three earthquakes of magnitude 7.0 to 7.5 occurred in the area during this time, with several aftershocks between 6.0 and 6.5, and around one-hundred between 5 and 5.9 (USGS). Other large events from the New Madrid Seismic Zone came in 1843 and 1895 with magnitudes of 6.0 and 6.6 respectively. Recent activity in the zone includes a magnitude 5.4 event in 1968. Shown by Figure 7 are the known significant earthquakes having occurred in the New Madrid and Wabash Valley Seismic Zones. Seismic events are anticipated to pose a minimal risk to the project site.

Figure 7 – Seismic Zone Map (USGS)

Site

Crane, Indiana

6. Subsurface Conditions The following sections outline the subsurface conditions and laboratory testing program. Information regarding specific locations are included in various sections of the attached Appendices.

6.1 Borings & Test Pits

The soil borings and test pits were completed on site between April 16th and June 14th of 2019. The following is a summary of the elevations recorded.

Table 2 – Approximate Boring Surface and Termination Elevations

Boring Designation

Ground Surface

Elevation (ft)

Boring Termination Elevation (ft)

Boring Designation

Ground Surface

Elevation (ft)

Boring Termination Elevation (ft)

B-1 717.0 536.4 B-41 719.8 719.8 B-2 714.7 514.2 B-51 720.8 705.8

B-3 710.3 509.8 TP-1* 724.0 715.0

B-4 721.6 521.6 TP-2* 716.0 708.5

B-5 721.9 520.9 B-30* 721.0 713.6 B-6 719.5 519.5 B-31* 700.0 690.5 B-7 719.6 519.6 B-32* 700.0 689.0 B-8 720.3 519.3 B-33* 710.5 700.0 B-9 719.3 519.3 B-34* 710.5 700.0

B-10 719.2 519.2 B-35* 719.5 709.0 B-11 720.1 520.1 B-36* 723.1 713.7 B-21 721.2 712.2 B-37* 730.0 719.5 B-22 718.9 712.4 B-38* 730.0 719.5 B-23 718.3 704.6 B-39* 720.5 711.4 B-24 718.2 710.2 B-40* 714.2 704.8 B-25 706.5 687.4 B-41* 719.8 719.8 B-26 721.5 711.6

*Estimated from surveyed site topography.

Launch Pit Site - In general, the borings encountered approximately 10 feet of residual soils overlying approximately 30 feet of weathered rock and then solid rock. The residual soils consisted of a thin layer of clay (CL/CH) overlying dense to very dense silty to clayey sand (SC/SM). The sand mixtures typically decreased in clay content with depth, were often weakly cemented, and exhibited a residual bedrock structure. A thin layer of coal, less than one foot in thickness, preceded auger refusal in most of the borings. Refusal typically occurred on weathered bedrock at approximately ten feet below ground surface (bgs).

Table 3 briefly summarizes the range of results from the field and from laboratory testing programs in the Launch Pit Area. Please refer to the boring logs in Appendix B, profile diagrams in Appendix C, and laboratory data in Appendix F for more specific information.

Crane, Indiana

Table 3 – Summary of Subsurface Conditions (Launch Pit Area)

Soil Strata Type A pp ro x.

E le va tio n R an ge

, f ee t

St an da rd

Pe ne tra tio n, N

M oi st ur e Co nt en t, Un co nf in ed St re ng th ,t sf

Dr y

Un it

W ei gh t, pc f

Fi ne s Co nt en t, Li qu id L im it, Pl as tic L im it, Soft to Firm Clay 705- 720 0- 6 19-35 ― ― 75-96 36-43 18-19 Stiff to Hard Clay 699-715 9-52 14-25 1.1-3.2 106-112 50-95 23-57 13-18 Silty to Clayey Sand 702-715 22-100 1-34 ― ― 21-50 0-29 0-13

SSR = Split Spoon Refusal (greater than 50 blows for one, 6-inch increment)

Auger refusal materials were encountered within each of the launch pit area borings at depths ranging from about 6½ feet at boring B-22 to 19 feet at Boring B-25. Refusal is a designation applied to materials that cannot be further penetrated by the power auger with ordinary effort and is normally indicative of a very hard or very dense material, such as boulders or gravel lenses or the upper surface of bedrock. Weathered bedrock typically consisted of 10 feet of hard sandstone followed by weathered shale. The upper 15 feet of weathered shale was found to be severely weathered and was often weathered to a rapidly slaking clay. Core losses were not uncommon within this layer. The degree of weathering was found to gradually decrease with depth until fresh shale was encountered.

The underlying bedrock was composed of a mixture of soft shales and sandstones. Except for a relatively homogenous sandstone layer found between approximate elevations of 645 and 620 feet and a homogenous shale layer found below elevation 570 feet, the shales and sandstones were often thinly interbedded together.

However, the presence of unique bedding structures allowed for the delineation of individual stratigraphic units.

A total of 11 generalized rock layers were identified during the exploration program. Table 4 lists each of these layers and the approximate elevations at which they were encountered. It should be noted however that these 11 rock layers include minor interbeds of different rock types and that variations exist within their thicknesses and elevations. More detail on the subsurface conditions encountered can be found in the boring logs attached in Appendix B.

Table 4 – Summary of Lithological Units

Unit Name Bottom Elevation (ft.) Thickness (ft.)

Range Typical Range Typical

Weathered Sandstone 700 to 705 702 0 to 9 8 Severely Weathered Shale to Clay 685 to 700 697 2 to 15 4 Weathered Shale 684 to 692 691 0 to 9 7 Shale Interbedded with Sandstone

– Churned 677 to 687 684 3 to 10 7

Sandstone Interbedded with Shale –Churned 648 to 658 651 27 to 37 29

Coal and Shale 638 to 654 647 4 to 14 6 Sandstone 614 to 626 621 16 to 33 25 Turbidites and/or Shale 601 to 612 610 6 to 19 11 Sandstone 595 to 605 603 7 to 10 7 Shale Interbedded with Sandstone –Wavy Bedding 578 to 587 586 14 to 19 17

Shale and Claystone End of Boring End of Boring — —

Evidence of soft sediment deformation prior to lithification to rock was found in borings B-1, B-3, B-5, B-9, and B- 10 between elevations 626.0 feet and 601.0 feet. These “turbidites” were largely composed of steeply dipping

Crane, Indiana shales that were very thinly interbedded with sandstone. The very thin sandstone layers were frequently found to be discontinuous and were often displaced millimeters to centimeters at the core scale, indicating some form of shear displacement had occurred. However, fracturing was not found in association with the apparent shear planes. Homogenous shale or claystone was generally found at the same elevations in the remainder of the borings, making it difficult to determine if this lithology is ubiquitous at the site. While it is our opinion that the rock had not been deformed because of faulting or folding, the steep dip of this layer may be of concern in regard to stability and potential for wedge failures.

Entrance Drive - A total of 11 borings were drilled along Highway 486 between the main project site and Highway

331. Each boring was drilled to approximately 10 feet or to auger refusal, whichever was encountered first. Auger refusal was only encountered in three borings, Borings B-36, B-39, and B-40, indicating a highly variable bedrock surface. When bedrock was encountered, it was composed of severely weathered sandstone, with and without an overlying seam of coal. The overlying soils typically consisted of up to 6 feet of loose to medium dense clayey gravel overlying firm to stiff to lean clay (CL). Gravel was absent in the borings located closest to the main site (Borings B-30, B-31, and B-32). A summary of the conditions encountered in the 11 roadway borings is provided in Table 5.

Table 5 – Summary of Subsurface Conditions (Entrance Drive)

Soil Strata Type A pp ro x.

E le va tio n R an ge

, f ee t

St an da rd

Pe ne tra tio n, N

M oi st ur e Co nt en t, Un co nf in ed St re ng th , t sf

Dr y

Un it

W ei gh t, pc f

Fi ne s Co nt en t, Li qu id L im it, Pl as tic L im it, Loose to Medium Dense Clayey Gravel

710-728 6-69 11-20 --- --- 19-58 29-50 12-20

Firm to Stiff Clay 689-719 3-100 10 - 26 --- 114 56-95 31-70 12-20 SSR = Split Spoon Refusal (greater than 50 blows for one, 6-inch increment)

Auger refusal materials were encountered within three of the 11 entrance drive borings at an approximate depth of six feet (B-36, B39 and B-40). Refusal is a designation applied to materials that cannot be further penetrated by the power auger with ordinary effort and is normally indicative of a very hard or very dense material, such as boulders or gravel lenses or the upper surface of bedrock. Based on the nearby borings for the ULTF, refusal is likely being encountered on shale/sandstone bedrock.

The above subsurface description is of a generalized nature to highlight the major subsurface stratification features and material characteristics. The boring logs included in the Appendix should be reviewed for specific information at individual boring locations. These records include soil/rock descriptions, stratifications, penetration resistances, and locations of the samples and laboratory test data. The stratifications shown on the boring logs represent the conditions only at the actual boring locations. Variations may occur and should be expected between boring locations. The stratifications represent the approximate boundary between subsurface materials and the actual transition may be gradual. Water level information obtained during field operations is also shown on these boring logs. The samples that were not altered by laboratory testing will be retained for 60 days from the date of this report and then will be discarded.

6.2 Test Pits & Bulk Sampling

To supplement the geotechnical borings, two test pits were performed on the site for obtaining bulk samples for additional laboratory testing. Test pit TP-1 was located on the east end of the main site near the east entrance drive and extended to a depth of roughly nine feet. Test pit TP-2 was located on the south end of the site near the proposed filtration plant and extended to a depth of seven feet. The material encountered in each of the test

Crane, Indiana pits were consistent with those noted in the borings. The location of each of these test pits are shown in Appendix A. Additional bulk samples were collected from the surface of borings B-35 and B-40.

From the bulk samples collected, five modified Proctor tests were performed in general accordance with ASTM D 1557. The table below summarizes the optimum moisture content with the corresponding maximum dry unit weight. The complete dry unit weight – moisture relationship is included in Appendix F.

Table 6 – Summary of Proctor Results

Sample Optimum Moisture Content, %

Maximum Dry Unit Weight, pcf

Testing Method

B-35, 1-foot 8.4 132.5 Method C B-40, 1-foot 9.1 130.0 Method C TP-1, 4-foot 13.4 117.2 Method A TP-2, 4-foot 12.7 115.7 Method A TP-2, 6-feet 10.3 124.0 Method A

Two (2) California Bearing Ratio (CBR) analyses were completed using the composite materials based on the results of the modified Proctor. The dry density of each test series was varied relative to the material’s modified Proctor. A CBR value was measured at three different unit weights per ASTM D 1883 to develop a relationship between density/compaction and CBR values. The table below outlines the interpolated CBR values for typical compaction percentages:

Table 7 – Summary of CBR Results

Sample Dry Density (pcf)

Compaction* (%) CBR Value

B-35, 1-foot

115.8 87% 2.3

127.8 96% 11.8

132.6 100% 17.4

B-40, 1-foot

116.1 89% 1.9

124.4 96% 5.8

130.2 100% 25.0

TP-1, 2-feet

109.3 97% 7.2

111.1 98% 11.3

113.0 100% 15.4

TP-2, 4-feet

106.2 94% 3.0

109.4 97% 3.5

112.4 100% 4.8

*Compaction based on Reference Modified Proctors

From the bulk samples collected, thermal resistivity tests were performed on 3 remolded samples compacted to approximately 95% of the materials’ modified Proctor.

Table 8 – Summary of Thermal Results

Sample Dry Density (pcf)

Moisture Content (%)

Thermal Resistivity (°C-cm/W)

Dry Wet TP-1, 4-foot 111 13 99 49 TP-2, 4-foot 110 13 105 48 TP-2, 6-feet 118 10 93 43

Crane, Indiana

6.3 Geophysical Testing

Jacobs contracted with Terracon to provide geophysical testing that included Multi-channel analysis of surface waves (MASW) and Electrical Resistivity Imaging (ERI). For this project, Terracon utilized 12 overlapping arrays with six aligned in a general north-south direction and six in an east-west direction. The locations of the MASW lines are shown as solid red lines on the “Geophysical Survey Location Plan” in Terracon’s Geophysical report in Appendix E of this report. Based on the two-dimensional profiles, the shear wave velocity of the upper 10 to 30 feet generally ranges from 800 to 2,000 ft/s gradually stepping up with depth. Below a depth 30 feet, shear wave velocities of 2,000 ft/s to 5,000 ft/s were recorded with the shear wave velocities generally increasing with depth though isolated zones of higher velocity materials encountered between depths of 30 feet to 80 feet. Higher velocities are indicative of rock and other more difficult materials where excavation might not be routine. Lower velocities can be indicative of fill material, debris, and/or muck or other soft zones that may require remediation during construction. Shown by Figure 8 below is a graphic from the FHWA 2003 Geophysical Methods Technical Manual (DTFH68-02-P-00083) illustrating typical shear wave velocities for different materials.

Figure 8 - Typical Shear Wave Velocities (FHWA)

Terracon performed eight two-dimensional ERI arrays with five of the profiles performed in a North-South direction and three in an East-West direction. These are noted as blue lines on the “Geophysical Survey Location Plan” in Terracon’s Geophysical report.

Table 9 is from the FHWA 2003 Geophysical Methods Technical Manual (DTFH68-02-P-00083) showing the typical resistivity ranges for different materials. In general, lower resistivities occur in loose or medium dense, saturated materials due to the presence of water. High resistances often occur in dense or unsaturated materials.

Table 9 – Typical Electrical Resistivities of Earth Materials (FHWA)

Material Resistivity (W-m) Clay 1-20 Sand, Wet to Moist 20-200 Shale 1-500 Porous limestone 100-1,000 Dense limestone 1,000-1,000,000 Metamorphic rocks 50-1,000,000 Igneous rocks 100-1,000,000

Based on the geophysical information, the ERI profiles were generally consistent with the profiles developed from the shear wave testing. The recorded electrical resistivity values between elevations 690 and 720 feet generally ranged from 200 to 500 ohm-meters. From elevation 650 feet to 690 feet, resistivity values of less than 20 ohm-meters were encountered with a higher concentration on the south end of the site. In general, resistivity values below elevation 650 feet exceeded 100 ohm-meters, consistent with an intact material. On the south end of Line

Sh ea r W av e Ve lo ci ty , f t/ s

2,500

7,500

5,000

10,000

Crane, Indiana

4 and the center of Lines 3 and 7, resistivity values of less than 20 ohm-meters were encountered below an elevation of 570 feet indicating a significant zone of weathering may exist in this zone.

6.4 Water Level Measurements and Piezometers

Free water was observed in four of the 28 borings during or at the end of drilling and was measured at depths between approximately seven feet and 66 feet. The groundwater level at the site, as well as perched water levels and volumes, will fluctuate based on variations in rainfall, snowmelt, evaporation, surface run-off and other related hydro-geologic factors. The water level measurements presented in this report are the levels that were measured at the time of the field activities. Based on the laboratory program, saturated soils were identified as shallow as five feet bgs. Based on laboratory testing and the topographic setting, the ground water table at the time of drilling is estimated to be between 653 and 711 feet.

A summary of the observed groundwater conditions is presented in Table 10. These observations are based upon measurements during field operations between April and May of 2019 and were measured using an electronic water level indicator.

Table 10 – Groundwater Observations

Boring No.

Ground Surface

Elevation (ft.

NAVD88)

Groundwater During Drilling

(ft. NAVD88)

Groundwater End of Drilling

(ft. NAVD88)

Depth Elevation Depth Elevation

B-2 714.7 None Observed

None Observed 52.5 662.2

B-5 721.9 10.6 711.3 None Observed

None Observed

B-9 719.3 None observed

None Observed 66 653.3

B-24 718.2 7 711.2 None observed

None Observed

A series of three piezometers were installed to monitor long-term ground water levels across the site. The piezometers were installed to depths of 15ft, 73ft, and 173ft and are demarked as B-51, B-41, and B-2 respectively.

Piezometers B-51 and B-41 were drilled separately from the borehole series while piezometer B-2 was installed after packer testing of Boring B-2. The outer diameter of each piezometer borehole was reamed to six inches, to allow for a two-inch well pipe and two inches of annular space, in accordance with Unified Facilities Guide Specifications 33 51 39 (Monitoring Wells). A bentonite plug with a minimum thickness of two feet was placed in the bottom of each piezometer borehole followed by roughly two feet of course, filter sand. Each well pipe, with a flush, closed end cap and a ten-foot screen, was then placed on top of the coarse filter sand. Additional filter sand was placed around the well pipe to roughly two feet above the top of the ten-foot screen. Construction of the wells was completed by placing bentonite chips above the filter sand, a minimum of two feet thick, allowing the bentonite to hydrate and isolate the piezometer screen interval, and then grouting to the surface.

Table 11 summarizes the long-term water levels taken to date. Well screens were placed either based on the elevation of groundwater observed during drilling or based upon the condition of the rock core observed as well as the results of the packer testing. Based on the results of the recorded long-term water levels, three distinct aquifers or perched water zones have been identified. Water levels have been noted to be consistent during the period recorded to date, with the only exception being a drop of approximately 10 feet between August 2 and August 9, 2019.

Crane, Indiana

Table 11 – Long-term Water Readings Summary.

Piezometer B-2 (length 175-ft) Piezometer B-41 (length 73-ft) Piezometer B-51 (length 15-ft) Reading

Date Water Elevation

(ft. NAVD88) Reading

Date Water Elevation

(ft. NAVD88) Reading

Date Water Elevation

(ft. NAVD88)

7/17/2019 596.0 7/17/2019 655.9 7/17/2019 716.7

7/19/19 596.0 7/19/19 655.8 7/19/19 716.7

7/24/19 596.0 7/24/19 655.6 7/24/19 716.4

7/26/19 596.0 7/26/19 655.3 7/26/19 716.3

7/31/19 596.0 7/31/19 655.2 7/31/19 716.4

8/2/19 596.0 8/2/19 655.1 8/2/19 716.3

8/9/19 585.2 8/9/19 654.8 8/9/19 716.2

8/16/19 585.0 8/16/19 654.4 8/16/19 716.0

8/23/19 585.0 8/23/19 654.4 8/23/19 715.7

8/28/19 584.6 8/28/19 654.2 8/28/19 715.6

9/5/19 585.5 9/5/19 653.9 9/5/19 715.5

9/20/19 585.4 9/20/19 653.3 9/20/19 715.2

9/24/19 585.4 9/24/19 653.3 9/24/19 715.1

9/26/19 585.4 9/26/19 653.2 9/26/19 715.1

10/11/19 585.0 10/11/19 652.8 10/11/19 714.8

10/18/19 585.0 10/18/19 652.4 10/18/19 714.5

10/22/19 584.8 10/22/19 652.4 10/22/19 714.5

11/1/19 584.5 11/1/19 652.0 11/1/19 714.1

11/11/19 586.0 11/11/19 651.7 11/11/19 714.1

12/3/19 587.0 12/3/19 651.6 12/3/19 714.0

12/20/19 586.0 12/20/19 651.0 12/20/19 713.6

12/30/19 587.6 12/30/19 651.8 12/30/19 714.1

1/3/20 588.0 1/3/20 651.8 1/3/20 714.1

1/8/20 588.0 1/8/20 651.4 1/8/20 713.7

1/15/20 588.1 1/15/20 652.0 1/15/20 714.2

1/21/20 588.6 1/21/20 651.6 1/21/20 713.8

6.5 Packer Testing

Jacobs contracted Terracon to perform packer testing to measure the permeability of the bedrock using the US Army Corps of Engineer’s method EM 1110-2-1901 (1993). Testing was conducted in two borings ranging in depth from five to 195 feet. Packer testing involves the use of several inflatable, rubber bladders (i.e. packers) to isolate a specific interval within a borehole for infiltration testing. Pressurized fluid, most usually water, is injected into the isolated interval to measure the hydraulic conductivity of the interval at various pressures.

Crane, Indiana

A triple packer system was used for testing. The first (upper) packer seats in the bottom of the drill string to help stabilize the rest of the packer system and is slightly smaller in diameter than the lower two packers. The lower two packers grip the exposed borehole walls, isolating a specified interval for testing. Shown by the Figure 9 is a schematic of the packer assembly used during testing.

Packer testing was conducted in boreholes B-2 and B-5. Testing was conducted in 10-foot increments for the entirety B-5 and most of B-2. The two boreholes had already been drilled by the time packer testing was conducted, so the tests were conducted starting at the deepest interval (185 feet to 195 feet bgs) working upwards towards ground level to prevent downward migration of water from affecting subsequent test intervals.

Figure 9 – Triple packer assembly used for packer testing (RTS Instruments Ltd.).

During each individual test, water pressure was incrementally raised then lowered within the isolated interval. The maximum pressure used for each interval was roughly 50% greater than what would be experienced by the interval midpoint if groundwater were at the surface. For example, for a test conducted between 85 and 95 feet bgs, the pressure at 90 feet would be 39 psi if groundwater was at the surface. A fifty percent increase from 39 psi is just below 60 psi, thus 60 psi was used for the maximum pressure. Each interval was subjected to several lower pressures before and after reaching the maximum pressure. For the same interval, the full sequence of pressure steps was 20, 40, 60, 40, and 20 psi. At each pressure step, flow and rate of flow into the formation was recorded for at least five minutes. If after five minutes no flow was being recorded, the pressure within the interval was cut off from the water return circuit and the time to dissipate pressure was monitored, what is commonly referred to as a shut-in test. The shut-in test helps confirm validity of flow data; intervals with high flow should dissipate pressure quickly while intervals with little to no flow should dissipate pressure slowly. After the testing at each pressure step was completed, the packers were deflated, and the entire assembly was retracted 10 feet towards the surface to test the next interval.

Crane, Indiana

The core taken from each borehole was fairly high quality, with RQD values often 85 or greater. Before testing began, it was expected that flow would be confined to fragmented sandstone and siltstone zones and the various coal beds. These presumptions were largely correct, with almost all flow being confined to the various coal beds.

The most flow noted in B-2 was between depths of 55 feet and 65 feet bgs with roughly 130 gallons of infiltration.

Between depths of 165 feet and 175 feet a total of 25 gallons of infiltration was recorded. These intervals generally correspond to coal seams logged during rock core sampling; the first between 60 feet and 65 feet bgs, the second roughly six-inches thick at 169 feet bgs. Similar flows into B-5 were noted at roughly these same depths; 56 gallons between 55 feet and 65 feet, and 13 gallons between 165 feet and 175 feet. The upper coal seam in B-5 is roughly 69 feet bgs, and it is most likely that the 56 gallons which infiltrated the interval from 55 feet to 65 feet was permeating this coal seam. The stratigraphy from 55 feet to 65 feet is composed of an extremely competent sandstone/shale matrix that often has just a few tight fractures in a ten-foot run whereas the coal seam at 69 feet is highly fractured with open, unfilled joints. Furthermore, no flow in this competent sandstone/shale matrix was recorded in any other interval in either borehole. A summary of the packer testing is shown by Table 12 below, while the raw data taken by Terracon in the field is contained in Appendix F.

A possible reason for the relatively low permeability is that the boreholes remained open for roughly a month before packer testing was conducted; fractures and voids in the borehole walls immediately after drilling could have been closed by fine-grained material and saturated by water in the borehole between drilling and packer testing. Another reason for the low permeability was the relatively intact nature of the bedrock encountered. Based on the high RQD and the high percentage of shale and claystone encountered, high permeabilities were not expected.

The most common problem associated with the packer tests conducted for the project was leaks in the packer assembly using the initial packer test setup. There were multiple instances in which flow was being recorded only to realize the system was leaking at either a connection between drill string pipes or was slowly trickling from the annular space between the drill stem and the borehole, indicating water from the isolated zone was escaping around the upper borehole packer. There is little that could have been done about either of these leaks, the drill strings were always screwed together firmly, and the packers were inflated to very near the maximum suggested inflation pressure. However, if the flow from the leaking system governed the behavior of the tests, the order of magnitude of the resulting hydraulic conductivity would be negligible.

Table 12 – Summary of Packer Testing Results

Boring No.

Depth

(feet bgs) Permeability

(gal/min) Boring No.

Depth

(feet bgs) Permeability

(gal/min)

B-2 15-25 Not Tested B-5 15-25 0

B-2 25-35 Not Tested B-5 25-35 0

B-2 35-45 0 B-5 35-45 0

B-2 45-55 Not Tested B-5 45-55 0

B-2 55-65 2.5-5.8 B-5 55-65 1.5-4

B-2 65-75 0 B-5 65-75 0-1.2

B-2 75-85 0 B-5 75-85 0

B-2 85-95 0 B-5 85-95 0

B-2 95-105 0 B-5 95-105 0

B-2 105-115 Not Tested B-5 105-115 0

B-2 115-125 0 B-5 115-125 0

B-2 125-135 0 B-5 125-135 0

Crane, Indiana

Boring No.

Depth

(feet bgs) Permeability

(gal/min) Boring No.

Depth

(feet bgs) Permeability

(gal/min)

B-2 135-145 Not Tested B-5 135-145 0

B-2 145-155 0 B-5 145-155 1-2

B-2 155-165 Not Tested B-5 155-165 0

B-2 165-175 0-3.2 B-5 165-175 0-1.6

B-2 175-185 Not Tested B-5 175-185 0

B-2 185-195 0-0.8 B-5 185-195 0-0.4

6.6 Infiltration/Percolation Testing

A series of infiltration/percolation tests were performed on surficial soils across the site. The testing included two double ring infiltrometer tests, performed in accordance with ASTM D3385, and four falling head percolation tests.

The purpose of these tests was to approximate vertical infiltration rate of the subsurface materials to aid in the design of the proposed detention basins.

A double-ring infiltration requires driving two open-ended, stiff metal rings into the ground, centered around the same point, then maintaining a constant head within the rings and recording the volume of water added to each ring at predetermined time increments. These tests were conducted on the surface though they can also be performed in excavated test pits. The purpose of the outer ring is to promote pure vertical infiltration beneath the central ring to more closely approximate vertical infiltration rate. While vertical infiltration rate can be calculated from both the inner ring and the annular space between rings, the rate derived from the inner ring is more accurate as it is assumed its flow is more nearly vertical.

Falling head percolation tests measure soil infiltration rate by the change in water level within a cavity of known volume, created by boring a shallow hole with a drill rig or a posthole digger, over time. The results from these tests are a product of using the average water height over a given time interval to find percolation rate. Percolation rate is used here to distinguish from vertical infiltration rate as water was permeating the soil both vertically and horizontally. The results are closer to a horizontal infiltration rate as the area of the borehole walls was much greater than the area of the borehole bottom.

The results from both the double-ring infiltration tests and the falling-head percolation tests are shown in Table

13. The results for the double-ring infiltration tests are those taken from the inner ring. For each falling-head percolation test there are two infiltration rates reported; the first is that given by Terracon, the second is a modified rate calculated by Jacobs to more closely approximate vertical infiltration rate. The modified rate accounts for only the area of the bottom of the borehole and implements a correction factor to account for the variable water level throughout the test. A full report of these tests is shown in Appendix F.

Table 13 – Summary of Infiltration Test Results

Test ID Test Location (Lat./Long)

Test Depth (ft.)

Infiltration Rate (in./hr.)

Modified Infiltration Rate (in./hr.)

Double-Ring Infiltration Test 1

(DRI-1)

38.89135°N 86.86396°W At Surface 0.15 -

Double Ring Infiltration Test 2

(DRI-2)

Near B-24 At Surface 0.05 -

Crane, Indiana

Test ID Test Location (Lat./Long)

Test Depth (ft.)

Infiltration Rate (in./hr.)

Modified Infiltration Rate (in./hr.)

South Basin 1

(SB-1)

38.89057°N 86.86569°W

(+5 feet North)

4.5 0.05 0.11

South Basing 2

(SB-2)

38.89057°N 86.86569°W

(+5 feet South)

6.5 0.02 0.04

North Basin 1

(NB-1)

38.89215°N 86.86535°W

(+5 feet North)

4.3 0.03 0.06

North Basin 2

(NB-2)

38.89215°N 86.86535°W

(+5 feet South)

8.3 0.03 0.05

7. Evaluation & Commentary Based on the geotechnical and project information available, Jacobs has identified five geotechnical items that will control the behavior of the proposed structures and will impact the proposed development:

1. The shear strength and compressibility of the upper soils will control the behavior of the proposed grade supported structures.

2. Relatively shallow rock was encountered that will impact the excavation for the proposed launch pit and may impact construction of the above grade structures and utilities.

3. Ground water may be present within the limits of deep utility and foundation excavations that may require dewatering or alternative construction methods.

4. Drying of some of the on-site soils may be required to achieve proper compaction during grading. Amendment of the underlying soils should be anticipated during wetter portions of the year.

5. Relatively sensitive soils were encountered in the upper parts of the borings that may present mobility challenges with conventional equipment.

7.1 Shear Strengths and Compressibility of Soils

The primary geotechnical property controlling the bearing capacity and compressibility of the above grade structures is the shear strength of the near surface soils. Based on up to four feet of fill and a shallow foundation bearing at a depth of three feet below exterior or adjacent grades, the applied foundation load on a shallow foundation up to five feet wide will be distributed through the 10 to 15 feet of soil generally beneath the footing. It is estimated that the shear strength of the overburden soils at the site ranges from 800 pounds per square foot (psf) to over 2,500 psf. It is anticipated that a new engineered fill constructed as described in this report should have a minimum shear strength of 1,500 psf. These shear strengths are considered “undrained” or a “total stress” parameter and will be used in conjunction with other physical and geometric parameters to calculate an allowable bearing capacity.

7.2 Shallow Rock

Weathered rock consisting of rock fragments in a clay matrix and weakly cemented sandstone was encountered at depths of 5 to 10 feet below the existing grade. Auger refusal was encountered at depths of approximately seven to 19 feet. Some of the weathered rock may be difficult to excavate, especially in the launch pit and deep utility trenches. Excavation machinery equipped with rock chippers may be required in some locations. In addition, intact ledges or boulders of sound and hard rock may be encountered within the weathered rock layers that could

Crane, Indiana increase excavation difficulty. Depending on the proposed finish floor elevation and proposed depth of utility trenches, it may be desirable to build the site up to minimize the amount of rock excavation required. Based on the strengths of the bedrock materials, blasting may be required in various rock stratums within the proposed launch pit. Further discussion on rock excavation techniques are discussed in Section 8.12.

7.3 Groundwater

Based on the borings, a perched water table was observed near the soil-rock interface which may readily flow into foundation and utility trench. Jacobs anticipates that most of the water in these excavations can be dewatered using localized submersible pumps. Based on the piezometer readings the static water table is estimated to be between elevations 653 feet and 717 feet which may require dewatering in the launch pit excavation. Based on the packer testing program, the bedrock materials are relatively impermeable. It is understood that the pit walls will consist of slurry panels; therefore, minor infiltration into the pit is anticipated.

Three distinct aquifers or perched water zones were identified during the drilling and packer testing. Piezometers were installed with screens to monitor seasonal groundwater fluctuation. Groundwater levels have been recorded in these piezometers from July through September 2019 and determined that three isolated groundwater zones exist and have maintained consistent levels (a noticeable drop of approximately 10 feet was noted in B-2, the deepest well screen). The upper groundwater zone ranges from four to six feet depth bgs (El. 715 to El. 717) and is located near the contact between the overburden and the weathered rock. This groundwater is likely the result of groundwater seepage through the overburden due to the heavy seasonal precipitation occurring during and subsequent the field activities. The next groundwater zone was observed from approximately 66 to 69 feet bgs (El. 653 to El. 656) and is located between sandstone rock and a weathered shale/coal seam. The lowest groundwater encountered was encountered from 121 and 132 feet bgs (El. 585 to El. 596) and was observed in a zone characterized by shale interbedded with sandstone with wavy or equal proportioned bedding. Since these groundwater zones are isolated from each other, with relatively impermeable zones between, the launch pit walls are not likely to see the full hydrostatic head from the upper two zones. The seal slab will likely only see the head from the deepest zone.

7.4 Compaction

Since the overburden soils at the site predominantly consists of silts and clays, it may become difficult to properly compact the soils because of high moisture contents.