95 Geotechnical Interpretation Report (GIR).pdf

Pipestem Dam (ND00146) Pipestem Creek, North Dakota

Geotechnical Interpretation Report Main Report

Northwestern Division Omaha District

Status: 95% Post-ATR/IEPR Date: April 2022

Controlled by: U.S. Army Corps of Engineers Controlled by: CENWO-ED CUI Category: General Critical Infrastructure Info Limited Dissemination Control: FEDCON POC: Ross Cullin, 402-995-2273

This page is intentionally left blank.

PIPESTEM DAM OMAHA DISTRICT

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DISCLAIMER AND LIMITATIONS

Disclaimer

This Geotechnical Interpretation Report (GIR) contains actual subsurface and other information that was collected at or adjacent to the Site by the Government, or for the Government, for use in preparing the Contract Documents. This GIR contains interpretive information. This GIR is a summary, the full-text interpretive documents, included in the interpretive appendices, are provided for completeness and for the information of the bidder. (A separate Geotechnical Data Report (GDR) and Non-Interpretive Appendices contains non-interpretive information) The bidders must make their own interpretations of the information provided in this report and the interpretive appendices and must not solely rely on the provided interpretations in preparation of their bids. Subject to that exception, the GIR is a Contract Document.

Limitations

The Government does not represent that the boring and test pit/trench logs, field and laboratory test results and other available geologic information show the conditions that will be encountered in performing the work. The Government represents only that such information shows conditions at the locations of the borings, test pits/trenches, or other field data collection locations at the time that the data were collected. Each bidder must form their own opinion of the character of the work and of the materials to be excavated, make their own interpretations, and satisfy themselves by their own interpretations and research regarding all conditions affecting the work to be performed. The Contractor must assume all responsibility for deductions and conclusions as to the nature or condition of all earth, rock and other materials to be excavated and the difficulties of making and maintaining the required excavations, and of performing other work affected by the geology and subsurface conditions at the Site.

The Contractor must assume that any kind of rock and soil may be encountered in excavations, including mud or other materials that are difficult to handle.

Limited Reliance by the Contractor on Technical Data Authorized: The Contractor may rely upon the general accuracy of the Technical Data contained in the GIR. Except for such reliance on this Technical Data, the Contractor may not rely upon or make any Claim against the Government with respect to:

a) the completeness of this report for the Contractor’s purposes, including but not limited to, any aspects of the means, methods, techniques, sequences, and procedures of construction to be employed by the Contractor, and safety precautions and programs incident thereto, or

b) interpretations and opinions contained in this report, or

c) Any Contractor interpretation of or conclusion drawn from any Technical Data or any such other data, interpretations, opinions, or information.

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REPORT FUNCTION

This report, the Geotechnical Interpretation Report (GIR), functions to provide a summary of interpretative reports, drawings, and figures for this project, created at different times. Some of the information within and attached was created by USACE, some by contractors working for USACE.

For more information, please see the full-text appendices that contain detailed reports for each specific subject.

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TABLE OF CONTENTS

1. SPILLWAY GEOLOGY INTERPRETATION

1.1 CONSTRUCTION FOUNDATION REPORT (1975)

1.2 SPILLWAY GEOTECHNICAL INVESTIGATION (2013 – REVISED 2017)

1.3 FIELD INVESTIGATION PROGRAM PLAN (CURRENT INTERPRETATION)

1.3.1 Overburden

1.3.2 Pierre Formation Shale

1.3.3 Optical Televiewer

1.4 REFERENCES

LIST OF FIGURES

Figure 1: Original interpretation of shale knob at end of spillway (CFR, Plate 3) Figure 2: Plan of borings (CFR, 1975) Figure 3: Record of borings - spillway section 1 (CFR, 1975) Figure 4: Record of borings - spillway section 2 (CFR, 1975) Figure 5: Record of borings - spillway section 3 (CFR, 1975) Figure 6: Record of borings - spillway section 4 (CFR, 1975) Figure 7: ReMI and 2D TDEM location map (USACE, 2017) Figure 8: Cross section line locations from 2013 spillway investigation (USACE, 2017) Figure 9: Cross section A-A’ from 2013 spillway investigation (USACE, 2017) Figure 10: Cross section B-B’ from 2013 spillway investigation (USACE, 2017) Figure 11: Cross section C-C’ from 2013 spillway investigation (USACE, 2017) Figure 12: Cross section D-D’ from 2013 spillway investigation (USACE, 2017 Figure 13: Cross section E-E’ from 2013 spillway investigation (USACE, 2017) Figure 14: Cross section F-F’ from 2013 spillway investigation (USACE, 2017) Figure 15: Cross section G-G’ from 2013 spillway investigation (USACE, 2017) Figure 16: Cross section H-H’ from 2013 spillway investigation (USACE, 2017) Figure 17: Cross section I-I’ from 2013 spillway investigation (USACE, 2017) Figure 18: Cross section J-J’ from 2013 spillway investigation (USACE, 2017) Figure 19: Cross section K-K’ from 2013 spillway investigation (USACE, 2017) Figure 20: Cross section L-L’ from 2013 spillway investigation (USACE, 2017) Figure 21: Cross section M-M’ from 2013 spillway investigation (USACE, 2017) Figure 22: Cross section N-N’ from 2013 spillway investigation (USACE, 2017) Figure 23: Cross section O-O’ from 2013 spillway investigation (USACE, 2017) Figure 24: Three-dimensional representation of spillway geology and ground surface topography (surficial sands and Pipestem Creek alluvium not shown) Figure 25: Plan view showing cross section locations - Figure B-1 in Appendix B Figure 26: Cross section A-A’ (5X vertical exaggeration) - Figure B-2 in Appendix B Figure 27: Cross section B-B’ (5X vertical exaggeration) - Figure B-3 in Appendix B Figure 28: Cross section C-C’ (5X vertical exaggeration) - Figure B-4 in Appendix B Figure 29: Cross section D-D’ (10X vertical exaggeration) - Figure B-5 in Appendix B Figure 30: Cross section E-E’ (10X vertical exaggeration) - Figure B-6 in Appendix B Figure 31: Cross section F-F’ (10X vertical exaggeration) - Figure B-7 in Appendix B Figure 32: Cross section of regional test holes near Pipestem Dam

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Figure 33: Regional top of bedrock contour map (modified from Winters, 1963). Black lines are 100-foot contours

Figure 34: Top of bedrock isocontour map – current interpretation (site) with spillway structure (red) Figure 35: Top of bedrock isocontour map – current interpretation (end of spillway) with spillway structure (red) .. 35 Figure 36: Photograph of Pierre Formation shale exposed on the slope face east of the coulee (note: gravel and cobbles on surface are eroded from the overlying glacial till) Figure 37: Paillet Ranking System chart Figure 38: Televiewer results from top of BH20-01 (left) and PZ19-20 (right) Figure 39: Stereonet pole (top and middle) and plane (bottom) diagrams from BH20-01 (left) and PZ19-20

(right) Figure 40: Rose diagram plots from BH20-01 (left) and PZ19-20 (right). Dip direction at top. Dip angle at bottom

LIST OF TABLES

Table 1-1: Televiewer fracture rankings (number per category)

LIST OF APPENDICES

Appendix A Spillway Geologic Profiles (FIPP) Appendix B Optical Televiewer Data and Plots (FIPP)

LIST OF ACRONYMS AND ABBREVIATIONS

FIPP Field Investigation Program Plan GDR Geotechnical Data Report GIR Geotechnical Interpretation Report K Hydraulic Conductivity LPD Local Project Datum S Storativity T Transmissivity

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1. SPILLWAY GEOLOGY INTERPRETATION

The following sections provide interpretations of the site geology from all previous investigations in the spillway area at Pipestem Dam. The foundation materials in the spillway area consist of discontinuous surficial sands, glacial clay till and glacio-fluvial sands, Pierre Formation shale bedrock, and Pipestem Creek alluvium. The foundation materials are discussed in more detail in the Geotechnical Data Report (separate cover).

1.1 CONSTRUCTION FOUNDATION REPORT (1975)

As part of the initial pre-construction investigation, 42 geotechnical borings were advanced in the spillway area as documented in the Construction Foundation Report (1975). The initial investigation determined that the spillway was founded entirely on soil materials, primarily lean and sandy glacial clays underlain by varying thicknesses of glacio-fluvial sands and gravels and Pierre Formation shale. As discussed in the Geotechnical Data Report (separate cover), these upper glacial clays were excavated and used as impervious borrow material in the embankment. Stick logs and cross sections from the Construction Foundation Report (1975) are included as Figure 2 through Figure 6. Note that original drill logs are not available from the pre-construction borings.

In the Construction Foundation Report (1975), one of the drawings (Plate 3) showed a prominent bedrock knob at the end of the spillway (Figure 1). The drawing is also included in Design Memorandum JP-5 (Plate 10). No boring logs in the area of the bedrock knob were found in any of the available documentation and a discussion of this specific feature was not found in any of the design documents or the Construction Foundation Report. There is mention of seven borings drilled near the end of the spillway in 1944 (three of which are shown as black circles on Figure 1) in Design Memorandum JP-3, which also notes that these 1944 borings were not included in the discussion of site geology as the top of bedrock data was not readily assimilated with other more recent borings. No record of these 1944 borings was found in any of the available documentation. No other borings deep enough to encounter bedrock were advanced in the area near the far end of the spillway. Note that top of bedrock contours have been revised using more recent boring data as discussed in Section 1.3.

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Figure 2: Plan of borings (CFR, 1975)

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Figure 3: Record of borings - spillway section 1 (CFR, 1975)

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Figure 4: Record of borings - spillway section 2 (CFR, 1975)

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Figure 5: Record of borings - spillway section 3 (CFR, 1975)

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Figure 6: Record of borings - spillway section 4 (CFR, 1975)

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1.2 SPILLWAY GEOTECHNICAL INVESTIGATION (2013 – REVISED 2017)

As discussed in the Geotechnical Data Report (separate cover), a geotechnical investigation was conducted by USACE in 2013. Due to the size of the area and known variability of the subsurface materials, it was determined that the most efficient approach would be to first conduct a geophysical investigation of the entire spillway area using both 2D resistivity profiles and seismic refraction microtremor (ReMi) soundings (Figure 7). The geophysical results were then reviewed and 13 targeted geotechnical boring locations (BH-01 through BH-13) were identified to verify and calibrate the geophysical data. Cross sections derived using data from the 2013 borings and boring data from the 1975 Construction Foundation Report are included as Figure 8 through Figure 23. Note that further refinements to the site conceptual model were made (most notably at the end of the spillway) using data collected during the 2018-2020 field investigation program plan (FIPP) investigations as shown on the interpretive sections included in Section 1.3.

Figure 7: ReMI and 2D TDEM location map (USACE, 2017)

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Figure 8: Cross section line locations from 2013 spillway investigation (USACE, 2017)

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Figure 9: Cross section A-A’ from 2013 spillway investigation (USACE, 2017)

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Figure 10: Cross section B-B’ from 2013 spillway investigation (USACE, 2017)

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Figure 11: Cross section C-C’ from 2013 spillway investigation (USACE, 2017)

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Figure 12: Cross section D-D’ from 2013 spillway investigation (USACE, 2017

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Figure 13: Cross section E-E’ from 2013 spillway investigation (USACE, 2017)

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Figure 14: Cross section F-F’ from 2013 spillway investigation (USACE, 2017)

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Figure 15: Cross section G-G’ from 2013 spillway investigation (USACE, 2017)

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Figure 16: Cross section H-H’ from 2013 spillway investigation (USACE, 2017)

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Figure 17: Cross section I-I’ from 2013 spillway investigation (USACE, 2017)

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Figure 18: Cross section J-J’ from 2013 spillway investigation (USACE, 2017)

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Figure 19: Cross section K-K’ from 2013 spillway investigation (USACE, 2017)

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Figure 20: Cross section L-L’ from 2013 spillway investigation (USACE, 2017)

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Figure 21: Cross section M-M’ from 2013 spillway investigation (USACE, 2017)

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Figure 22: Cross section N-N’ from 2013 spillway investigation (USACE, 2017)

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Figure 23: Cross section O-O’ from 2013 spillway investigation (USACE, 2017)

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1.3 FIELD INVESTIGATION PROGRAM PLAN (CURRENT INTERPRETATION)

The following sections provide a holistic interpretation of the site geology incorporating all available data, including both historical information and data from the Phase 1, Phase 2, and Phase 2 addendum work. To facilitate this discussion, a set of revised geologic cross sections across the spillway area is included as Appendix B. The foundation materials are discussed in more detail in the Geotechnical Data Report (separate cover).

The spillway materials at Pipestem Dam consist of (from top to bottom) discontinuous surficial sands and silts, glacial clay till, glacio-fluvial sands, and Pierre Formation shale bedrock (Figure 24). Pipestem Creek alluvium is also present in the valley area. A series of cross sections showing the foundation geology roughly parallel and perpendicular to spillway flow is provided in Appendix B. Snips of the cross sections are included as Figure 25 (plan view); Figure 26, Figure 27, and Figure 28 (parallel cross sections); and Figure 29, Figure 30, and Figure 31 (perpendicular cross sections). Note that locations and elevations for the spillway modification construction features (e.g., stilling basin) shown on the cross sections are approximate.

Figure 24: Three-dimensional representation of spillway geology and ground surface topography

(surficial sands and Pipestem Creek alluvium not shown)

PIPESTEM DAM

OMAHA DISTRICT

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Figure 25: Plan view showing cross section locations - Figure B-1 in Appendix B

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Figure 26: Cross section A-A’ (5X vertical exaggeration) - Figure B-2 in Appendix B

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Figure 27: Cross section B-B’ (5X vertical exaggeration) - Figure B-3 in Appendix B

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Figure 28: Cross section C-C’ (5X vertical exaggeration) - Figure B-4 in Appendix B

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Figure 29: Cross section D-D’ (10X vertical exaggeration) - Figure B-5 in Appendix B

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Figure 30: Cross section E-E’ (10X vertical exaggeration) - Figure B-6 in Appendix B

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Figure 31: Cross section F-F’ (10X vertical exaggeration) - Figure B-7 in Appendix B

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1.3.1 Overburden

As interpreted on the cross sections (based on available boring data), the surficial sands and silts are discontinuous across the spillway (and were removed and replaced over a large area as discussed in the Geotechnical Data Report). Where both are present, the glacio-fluvial sands are separated into an upper and lower unit by a layer of glacial clay till that is thickest in the middle of the spillway and thins out towards the left (east) side of the spillway. The upper glacio-fluvial sand unit is present primarily on the left (east) side of the spillway and widens laterally and vertically near the upstream and downstream ends (pinching out a bit in the center of the spillway). The upper glacio-fluvial sand unit is overlain and underlain by glacial clay till. The lower glacio-fluvial sand unit is present directly above the Pierre Formation shale across most of the spillway with the exception of the southwest corner where a bedrock high is present and the sand pinches out.

1.3.2 Pierre Formation Shale

As interpreted on the cross sections (based on available boring data), over most of the spillway, the Pierre Formation shale is relatively flat lying (around elevation 1,400 to 1,410 feet); however, in the southwest corner, the shale rises rather abruptly to around 1,447 feet (shown in magenta on Figure 25). Where the shale ridge (bedrock high) is present at the downstream end of the west coulee on both the east and west sides, the lower glacio-fluvial sands are absent (pinching out as the shale rises). West of the coulee, the foundation consists of glacial clay till overlying Pierre Formation shale (no upper or lower sands). East of the coulee, the foundation consists of glacial clay till overlying upper glacio-fluvial sands which in turn overlie the Pierre Formation shale.

Note that the location of the “shale knob” as shown on Figure 1 as a circular feature between the two coulees is now interpreted to be west of that location based on soil borings advanced through the area as part of the field investigations as well as visual observation and surface mapping of the slope as discussed in the Geotechnical Data Report (separate cover).

1.3.2.1 Regional Structure

A study of the bedrock geology of Stutsman County (Winters, 1963) shows that there is a considerable amount of relief on the bedrock surface. According to Winters, much of the dissection of the bedrock surface in the county took place in pre-glacial times with the exception of the areas of recent erosion caused by the James River and Pipestem Creek. A bedrock contour map and geologic cross section through the dam site from the Winters report (modified to show the location of the dam) are provided as Figure 32 and Figure 33. The location of the cross section is shown on Figure 33 (also see full size map included in Appendix A). Also shown on Figure 33 are isocontours showing the interpolated bedrock surface in the area of the dam compiled from test hole and existing water well data available at the time of the report (1963).

The cross section and interpolated bedrock surface map indicate that the dam is located on a bedrock high with a deep valley (bedrock low) located immediately west of the site. The valley to the west is infilled primarily with glacial till to depths of more than 100 feet with sand and gravel at the base (as shown in borings 140-64-8ccc and 140-64-9ccc). Note that the bedrock contours were developed prior to construction of the dam and did not include any of the site boring data.

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Figure 32: Cross section of regional test holes near Pipestem Dam

Figure 33: Regional top of bedrock contour map (modified from Winters, 1963). Black lines are 100-foot contours.

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1.3.2.2 Site-Specific Structure

The bedrock surface across the dam site is characterized by considerable relief. Over most of the area, the Pierre Formation shale is relatively flat lying (around elevation 1,400 to 1,411 feet). Closer to Pipestem Creek, however, areas of high shale are present. These bedrock ridges can be seen on both the left and right abutments of the main dam embankment, on the left bank side of the creek, and near the downstream end of the spillway.

As discussed in Section 1.1, one of the drawings (Plate 3) in the Construction Foundation Report (1975) showed a prominent bedrock knob at the end of the spillway as shown in Figure 1. One of the primary objectives of the initial FIPP investigation was to better define this feature. With each phase of field work, the structure and orientation of this feature was better defined as boring data, test pits, and surface mapping was conducted. The current interpretation is provided as Figure 34 and Figure 35. As presented on these figures, the shale knob is now interpreted as a ridge that extends across both sides of the right (west) coulee. Top of shale is estimated to be encountered as high as elevation 1,443 feet at the downstream end of the west coulee based on borings BH19-24 and BH19-37 (west side of coulee) and boring BH20-01 (east side of coulee). A photograph taken from the west coulee looking back towards the location of BH20-01 near the southwest corner of the spillway is included as Figure 36. The photograph shows flags placed during field mapping along with the approximate contact between the overlying glacial deposits and the top of shale on the east side and downstream slope of the west coulee (photo looking east).

Figure 34: Top of bedrock isocontour map – current interpretation (site) with spillway structure (red)

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Figure 35: Top of bedrock isocontour map – current interpretation (end of spillway) with spillway structure (red)

Figure 36: Photograph of Pierre Formation shale exposed on the slope face east of the coulee (note: gravel and cobbles on surface are eroded from the overlying glacial till)

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1.3.3 Optical Televiewer

Multiple low and high angle fractures were noted in all rock core borings advanced into the shale; none showed significant alteration or infilling; however, iron oxide staining and secondary metallic minerals were noted in some of the fractures. As noted in the Geotechnical Data Report (separate cover), an optical televiewer was used to get an in-situ image of two of the rock core borings (BH20-01 [referred to as Pipestem 20] and PZ19-20 [referred to as Pipestem 2]). The televiewer results are included as Appendix B. Stereonets, rose diagrams, and fracture tables with feature ranks were provided by Colog, Inc. in Lakewood, Colorado. The features observed on the log were characterized based on the Paillet Ranking System developed by the US Geological Survey, Water Resources Division, Borehole Geophysics Research Project. This system is a semi-subjective evaluation of transmissivity potential.

The ranking system assigns a number value between zero and five to observed features. A rank of zero indicates a feature that appears sealed – with no water likely passing through it. A rank of five indicates a major fracture with large openings or breakouts.

Figure 37: Paillet Ranking System chart

For the televiewer analysis of boring BH20-01 (Pipestem 20), a total of 102 fractures were recorded from 79 to 131.1 feet below ground surface (note that hollow stem augers were in place in the boring through the shale from 48.5 to 79 feet below ground surface so fractures in the upper part were not visible). Of the 102 fractures, the majority (75) had a 1 ranking (partially open cracks). The two fractures with 4 ratings (very wide crack or multiple interconnected fractures) and one of the 3 rated fractures (wide open crack) were located in the upper 0.3 feet. Only 4 of the 102 fractures were noted to be ranked 0 (closed).

It should be noted that BH20-01 is the only boring drilled at the site that had no drilling water return. All water added (several thousand gallons) went into the formation and was not observed to be exiting from the slope. In boring PZ19-20, 48 fractures were logged from 7.3 to 54.6 feet below ground surface. In this boring, there were no fractures ranked 4 or 5. Five of the fractures were ranked as a 3 (wide open crack); three in the upper 0.1 feet and two at the bottom of the boring (54.5 and 54.6 feet below ground

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surface). Half of the fractures in this boring were ranked 0 (closed). A summary is provided as Table 1-1. Data and plots are provided in Appendix C.

Table 1-1: Televiewer fracture rankings (number per category)

Designation Rank 0 1 2 3 4 5

BH20-01 4 75 19 2 2 0

PZ19-20 24 18 1 5 0 0

Figure 38: Televiewer results from top of BH20-01 (left) and PZ19-20 (right)

1.3.3.1 Stereonets and Rose Diagrams

Stereonets and rose diagrams showing the orientation and dip of the fractures encountered in borings BH20-01 and PZ19-20 are provided as Figure 39 (stereonet poles and planes), and Figure 40 (rose diagrams). Note that the planes were plotted using fracture data provided by Colog, Inc. using the website https://app.visiblegeology.com/stereonetApp.html.

https://app.visiblegeology.com/stereonetApp.html

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As is evident on the stereonet diagrams, the fractures observed in boring BH20-01 (left) are much more prevalent and also much more randomly oriented than the fractures observed in PZ19-20. Boring BH20- 01 was advanced through the area of the high shale ridge, where the rock is observed to be much more broken. In BH20-01, horizontal bedding fractures are evident as are several clusters of high angle fractures. Boring PZ19-20 is located in the valley area and has much less fracturing overall. The fractures in PZ19-20 are also predominantly low angle (assumed to be bedding plane fractures).

Figure 39: Stereonet pole (top and middle) and plane (bottom) diagrams from BH20-01 (left) and PZ19-

20 (right)

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Figure 40: Rose diagram plots from BH20-01 (left) and PZ19-20 (right). Dip direction at top. Dip angle at bottom.

1.4 REFERENCES

Huxel, C.J., Jr, and Petri, L.R. “Geology and Ground Water Resources of Stutsman County, North Dakota, Part II, Ground water basic data: North Dakota State Water Commission County Groundwater Studies 2 and North Dakota Geological Survey,” Bulletin 41, 1963.

Huxel, C.J., Jr, and Petri, L.R. “Geology and Ground Water Resources of Stutsman County, North Dakota, Part III, Ground water and its chemical quality: North Dakota State Water Commission County Groundwater Studies 2 and North Dakota Geological Survey,” Bulletin 41, 1965.

Manz and Biek. “Geology of the Jamestown Area,” Geologic Investigations No. 5, North Dakota Geological Survey, 1956.

USACE. “Pipestem Lake, North Dakota, Construction Foundation Report,” December 1975.

USACE. “Pipestem Creek Dam and Reservoir, Design Memorandum No. JP-3,” October 1969.

USACE. “Pipestem Creek Dam and Reservoir, Design Memorandum No. JP-5,” October 1970.

USACE. “Pipestem Creek Dam and Reservoir, Design Memorandum No. JP-7,” October 1976.

Winters, H.A., “Geology and Ground Water Resources of Stutsman County, North Dakota, Part I, Geology: North Dakota State Water Commission County Groundwater Studies 2 and North Dakota Geological Survey,” Bulletin 41, 1963.

Pipestem Dam (ND00146) Pipestem Creek, North Dakota

Geotechnical Interpretation Report Appendices

Northwestern Division Omaha District

Status: 95% Post-ATR/IEPR Date: April 2022

Controlled by: U.S. Army Corps of Engineers Controlled by: CENWO-ED CUI Category: General Critical Infrastructure Info Limited Dissemination Control: FEDCON POC: Ross Cullin, 402-995-2273

This page is intentionally left blank.

GEOTECHNICAL INTERPRETATION REPORT CUI

LIST OF APPENDICES

Appendix A Spillway Geologic Profiles (FIPP) Appendix B Optical Televiewer Data and Plots (FIPP)

Appendix A

Spillway Geologic Profiles (FIPP)

CB

CBCBCB

CB

CB

CB

CBCB

CBCB CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB

CB CB

CB

CB

CB

CB

F-F'

E-E'

D-D'

P-35

P-34

P-28

P-27

P-26

P-25

P-24

P-22

P-21

P-20

P-18

P-16

P-9P-6

P-48

P-33

P-15

P-13 P-12

P-11

P-10 P-7A (93-4)

P-43 (PZ95-4)

P-1

PZ19-03

S-9

S-8

S-7

S-6

S-5

S-4

S-3

S-2

S-1

S-24

S-23

S-22

S-21

S-20

S-19

S-18

S-17

S-16

S-14

S-12

S-10

E-41 E-40E-39E-38

E-36E-35E-34E-33E-32E-31

C-62

C-45

79-4

79-3

70-5

70-4

70-3

70-2

E-101E-100

C-108

C-107

C-105

C-103

BH-13

BH-11

BH-10

BH-09 BH-08

BH-07

BH-06 BH-05

BH-04

BH-03

BH-02

BH-01

70-78

70-77

70-72

70-71

70-69

70-6370-6270-6170-60

70-59 70-58

70-55

70-51 70-50

70-49

70-48

70-47

70-46

70-45

70-44

70-43

70-39

70-38

70-37

70-34

70-33

70-32

70-30

70-28

70-26

70-25

70-24

70-23

70-22

70-21

70-20

70-19

70-17

70-16

70-12

70-10

BH19-08

BH19-06

4-F(TT)

4-E(TT)

4-D(TT)

3-C(TT)

3-B(TT)

3-A(TT)2-E(TT)

2-D(TT)

2-B(TT)

1-F(TT)

1-E(TT)

1-D(TT)

1-C(TT)

1-A(TT)

S-15(TT)

S-13(TT)

S-11(TT)

P-39

P-31

P-30P-29

P-23

P-19

P-17

A- A'

B- B'

C- C'

PZ19-02

PZ19-04

PZ19-01

PZ19-20

PZ19-19

PZ19-18

PZ19-17

PZ19-16

PZ19-15

P-44 (PZ95-5)

PZ19-05

USGS

E-37

E-29E-28E-27

C-61 C-47

79-279-1

70-1

C-106

C-104C-102

BH-12

79-2A 70-79

70-75 70-74

70-73 70-70

70-56

70-52

70-42

70-40

70-31

70-29

70-27

70-18

70-15

70-14

70-13

BH20-01

BH19-37

BH19-36

BH19-35

BH19-34

BH19-33

BH19-32

BH19-31

BH19-30

BH19-29

BH19-28

BH19-27

BH19-26

BH19-25

BH19-24

BH19-23

BH19-22

BH19-12

BH19-10

BH19-07

5-A(TT)

2-C(TT)

2-A(TT)

1-B(TT)

Source: Esri, Maxar, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, USGS, AeroGRID, IGN, and the GIS User Community

LEGEND

&= Soil Boring

CB Glacial Drift Piezometer

CB

Upper Glacio-Fluvial Sand Piezometer

CB

Lower Glacio-Fluvial Sand Piezometer

CB

Pipestem Creek Alluvium Piezometer

CB Shale Piezometer

&* Relief Well

Profile Alignment

Topographic Isocontour (1 ft)

Top of Bedrock Isocontour (10 ft)

³

Pierre

St. Paul

Bismarck Minnesota

South Dakota

North Dakota

Iowa

Montana

Wyoming Nebraska

U.S. Army Corps of Engineers Omaha District Pipestem Dam Jamestown, ND

Geologic Profile Lines

October 2021 FIGURE B-1

500 0 500250 Ft

C O

R P

S O

F E

N G

IN

E

E R

S O

M A

H A

, N E

B R

A S

K A

D A

T E x1

JA

M

1:

0H :1

:3 0V

Well Screen and Filter Pack Interval

B-2

SW-SC - Well-Graded Sand with Clay

(SP)g - Poorly Graded Sand with Gravel (SP-SM)g - Poorly Graded Sand with Silt and Gravel

(SW)g - Well-Graded Sand with Gravel

N W

O _F

E N

C E

_B _S

IZ

E

_S E

N S

IN

G

_Z O

N E

P

IP

E S

T E

M _D

A M

_P E

D .G

P J

U S

A C

E _N

W O

.G D

T

/2 5/

LL

E-E'

PL

54321

D

C

B

A

Notes:

1. Elevations in Project Datum.

2. Vertical exaggeration 5x.

3. View looking downstream.

4. Boring profiles projected to cross section line. US = upstream, DS = downstream, CL = centerline.

5. Geologic contacts were generated using Surfer 16.0 and revised using professional judgment.

6. Groundwater measurements recorded 10/29/20. Reservoir at 1442.91.

7. See Plate B-1 for profile location. IDENTIFICATION

E le va tio n (f t)

Distance Along Baseline (ft)

(SW-SM)g - Well-Graded Sand with Silt and Gravel

SP - Poorly Graded Sand

SP-SM - Poorly Graded Sand with Silt

SW - Well-Graded Sand

(GP)c - Poorly Graded Gravel with Cobbles

No Sample - No Sample

Shale - Shale

Topsoil - Topsoil

A P

P R

D

E S

C R

IP

T

IO

N

SHEET

SM - Silty Sand

D A

T E

M A

R K

U . S

A

R M

Y E

N G

IN

E

E R

D

IS

T R

IC

T

NUMBER

OF ENGINEERS

Horizontal Scale in Feet

75.0 0.0 75.0 150.0 225.0

LITHOLOGY GRAPHICS

(CH)s - Fat Clay with Sand

(CL)s - Lean Clay with Sand

(CL-ML)s - Silty Clay with Sand

(CL/CH)s - Lean to Fat Clay with Sand

CH - Fat Clay

CL - Lean Clay

CL-ML - Silty Clay

CL/CH - Lean to Fat Clay s(CH) - Sandy Fat Clay s(CL) - Sandy Lean Clay

SC - Clayey Sand

(ML/CL)s - Clayey Silt with Sand

(SC-SM)g - Silty, Clayey Sand with Gravel

ML - Silt

OMAHA DISTRICT

A P

P R

D

A T

E D

E S

C R

IP

T

IO

N

US ARMY CORPS

D E

S

IG

N E

D B

Y

D W

N B

Y

C K

D B

Y

S O

LI

C

IT

A

T

IO

N N

O

C O

N T

R A

C T

N O

S

U B

M

IT

T E

D B

Y

F

IL

E N

A M

E

S

IZ

E

P

LO

T S

C A

LE

P

LO

T D

A T

E

F

IL

E N

U M

B E

R

M A

R K

(SM)g - Silty Sand with Gravel

(SP-SC)g - Poorly Graded Sand with Clay and Gravel

P ip es te m D am

Ja m es to w n, N D

C ro ss S ec tio n A

-A

5X V er tic al E xa gg er a tio n

1/

/2

F in es

S an d

G ra ve l

LL PLF

in es

S an d

G ra ve l

N

A'A

F-F' D-D'

1,350

1,360

1,370

1,380

1,390

1,400

1,410

1,420

1,430

1,440

1,450

1,460

1,470

1,480

1,490

1,500

1,510

1,520

1,530

1,540

0 100 200 300 400 500 600 700 800 900 1,000 1,100 1,200 1,300 1,400 1,500 1,600 1,700 1,800

60/0.4 60/0.2

N

LL PL

F in es

S an d

G ra ve l

N

LL PL

432 55

F in es

S an d

G ra ve l

108/0.8

N

BH19-06 (150' US)

ELEV. 1493.0

BH19-08 (CL)

ELEV. 1491.4

ELEV. 1444.1

BH19-23 (40' DS)

ELEV. 1491.7

BH19-25 (155' US)

BH19-35 (5' US)

ELEV. 1488.6

BH19-37 (CL)

ELEV. 1491.0

PZ19-02 (Lower Glacio-Fluvial Sands) PZ19-03 (Upper Glacio-Fluvial Sands)

185' US

ELEV. 1492.6

Pierre Shale

Glacial Till

1435.16 10/29/2020

PZ19-02

1436.20 10/29/2020

PZ19-03

2 22

LL PLF

in es

S an d

N

109/0.8

60/0.2

LL PL

F in es

S an d

G ra ve l

G ra ve l

N

LL PLF

in es

S an d

G ra ve l

N

60/0.4

Glacial Till

Glacio-Fluvial Sand

Glacial Till

Glacio-Fluvial Sand

Weir (Approximate Location) Current Ground Surface

D A

T E

M A

R K

U . S

A

R M

Y E

N G

IN

E

E R

D

IS

T R

IC

T

E-E' D-D'F-F'

1,360

1,370

1,380

1,390

1,400

P ip es te m D am

Ja m es to w n, N D

C ro ss S ec tio n B

-B

5X V er tic al E xa gg er a tio n

1/

/2

C O

R P

S O

F E

N G

IN

E

E R

S O

M A

H A

, N E

B R

A S

K A

D A

T E

JA

M

1:

0H :1

:3 0V

OMAHA DISTRICT

NUMBER

OF ENGINEERS

A P

P R

D

A T

E D

E S

C R

IP

T

IO

N

US ARMY CORPS

D E

S

IG

N E

D B

Y

D W

N B

Y

C K

D B

Y

S O

LI

C

IT

A

T

IO

N N

O

C O

N T

R A

C T

N O

S

U B

M

IT

T E

D B

Y

F

IL

E N

A M

E

S

IZ

E

P

LO

T S

C A

LE

P

LO

T D

A T

E

F

IL

E N

U M

B E

R x1

Bentonite - Bentonite

Shale - Shale

Topsoil - Topsoil

IDENTIFICATION

M A

R K

A P

P R

D

E S

C R

IP

T

IO

N

SHEET

54321

D

C

B

A

B-3

Well Screen and Filter Pack Interval

1,200 1,300 1,400 1,500 1,600 1,700 1,800

B'

1,410

1,420

1,430

1,440

1,450

1,460

1,470

1,480

1,490

1,500

1,510

1,520

1,530

1,540

0 100 200 300 400 500 600 700 800 900 1,000 1,100

N W

O _F

E N

C E

_B _S

IZ

E

_S E

N S

IN

G

_Z O

N E

P

IP

E S

T E

M _D

A M

_P E

D .G

P J

U S

A C

E _N

W O

.G D

T

/2 5/

E le va tio n (f t)

Distance Along Baseline (ft)

Horizontal Scale in Feet

75.0 0.0 75.0 150.0 225.0

LITHOLOGY GRAPHICS

CH - Fat Clay

CL - Lean Clay

CL-ML - Silty Clay

OH - Organic Clay/Silt s(CL) - Sandy Lean Clay

SC - Clayey Sand

(SC)g - Clayey Sand with Gravel

SM - Silty Sand

(SP)g - Poorly Graded Sand with Gravel

SP - Poorly Graded Sand

SP-SM - Poorly Graded Sand with Silt

SW - Well-Graded Sand

Notes:

1. Elevations in Project Datum.

2. Vertical exaggeration 5x.

3. View looking downstream.

4. Boring profiles projected to cross section line. US = upstream, DS = downstream, CL = centerline.

5. Geologic contacts were generated using Surfer 16.0 and revised using professional judgment.

6. Groundwater measurements recorded 10/29/20. Reservoir at 1442.91.

7. See Plate B-1 for profile location.

1,350

B

LL PL

90 27

94 4

58510

LL PL

N

Pierre Shale

60/0.4

G ra ve l

S an d

F in es

Glacial Till

Glacial Till

N

Glacial Till

LL PL

Glacio-Fluvial Sand

N

Glacio-Fluvial Sand

OW20-03 (Lower GFS) - 22' US

OW20-04 (Upper GFS) - 8' US

OW20-01 (Shale) - 24' US

ELEV. ~1492.4 ELEV. 1491.3

BH19-07 (85' DS)

BH19-22 (50' DS)

ELEV. 1427.6

ELEV. 1495.2

BH19-24 (60' US)

P-19 (CL)

ELEV. 1459.0

1432.25 10/29/2020

1435.45 10/29/2020

OW20-04

1433.65 10/29/2020

OW20-03

1421.35 10/29/2020

OW20-01

Current Ground Surface

Steps (Approximate Location)

Bentonite

Sand layer

Bentonite

NUMBER

OF ENGINEERS

A P

P R

D

A T

E D

E S

C R

IP

T

IO

N

US ARMY CORPS

x1

JA

M

1:

0H :1

:3 0V

Well Screen

C C'

D E

S C

R

IP

T

IO

N

SHEET

N W

O _F

E N

C E

_B _S

IZ

E

_S E

N S

IN

G

_Z O

N E

P

IP

E S

T E

M _D

A M

_P E

D .G

P J

U S

A C

E _N

W O

.G D

T

/1 1/

E le va tio n (f t)

Distance Along Baseline (ft)

0 100 200 300 400 500 600 700 800 900 1,000 1,100 1,200 1,300 1,400 1,500 1,600 1,700 1,800

Horizontal Scale in Feet

75.0 0.0 75.0 150.0 225.0

LITHOLOGY GRAPHICS

B-4

OMAHA DISTRICT

1/

/2

Limey Concretion

CL - Lean Clay

CL-ML - Silty Clay

OH - Organic Clay/Silt

SC - Clayey Sand

SC-SM - Silty, Clayey Sand

(SP-SC)g - Poorly Graded Sand with Clay and Gravel

SM - Silty Sand

(SP-SM)g - Poorly Graded Sand with Silt and Gravel (SW-SM)g - Well-Graded Sand with Silt and Gravel

SP - Poorly Graded Sand

SP-SM - Poorly Graded Sand with Silt

SW-SM - Well-Graded Sand with Silt

Bentonite - Bentonite

Shale - Shale

Topsoil - Topsoil

USGS 620 - Clay or Clay Shale

D A

T E

M A

R K

U . S

A

R M

Y E

N G

IN

E

E R

D

IS

T R

IC

T

C O

R P

S O

F E

N G

IN

E

E R

S O

M A

H A

, N E

B R

A S

K A

D A

T E

D

C

B

A

D E

S

IG

N E

D B

Y

D W

N B

Y

C K

D B

Y

S O

LI

C

IT

A

T

IO

N N

O

C O

N T

R A

C T

N O

S

U B

M

IT

T E

D B

Y

F

IL

E N

A M

E

S

IZ

E

P

LO

T S

C A

LE

P

LO

T D

A T

E

F

IL

E N

U M

B E

R

1,500

1,510

1,520

1,530

1,540

E-E' D-D'F-F'

M A

R K

A P

P R

Vibrating Wire Tip

Notes:

1. Elevations in Project Datum.

2. Vertical exaggeration 5x.

3. View looking downstream.

4. Boring profiles projected to cross section line. US = upstream, DS = downstream, CL = centerline.

5. Geologic contacts were generated using Surfer 16.0 and revised using professional judgment.

6. Groundwater measurements recorded 10/29/20. Reservoir at 1442.91.

7. See Plate B-1 for profile location.

P ip es te m D am

Ja m es to w n, N D

C ro ss S ec tio n C

-C

5X V er tic al E xa gg er at io n

1,350

1,360

1,370

1,380

1,390

1,400

1,410

1,420

1,430

1,440

1,450

1,460

1,470

1,480

1,490

68 44 67 50

84 46

LL PL

IDENTIFICATION

N

PZ19-18 (110' US)

LL

ELEV. 1491.3

Pierre Shale

47 20

PZ19-20 (250' DS)

ELEV. 1411.8

Glacio-Fluvial Sand

Glacial Till

Glacial Till

ELEV. 1411.4

PZ19-16

(175' DS)

BH20-01 (60' US)

ELEV. 1491.3

G ra ve l

S an d

F in es

58510

7 90

90 27

ELEV. 1418.3

SHALE6 (2' DS)

ELEV. 1446.3

PZ19-15 (50' DS)

PL

43 21

PZ19-17

(230' DS)

PZ19-19

(260' DS)

ELEV. 1412.0

ELEV. 1424.2

BH20-07 (110' US)

ELEV. 1491.3

1414.39 10/21/2020

1415.09 10/29/2020

1421.57 10/29/2020

1423.64 (during drilling)

1408.60 10/29/2020

1407.77 10/21/2020

1415.83 10/29/2020

Current Ground Surface

Stilling Basin (Approximate Location)

Bentonite

Concretion

Concretion

Bentonite

Bentonite

Bentonite

Bentonite

Bentonite

Bentonite Bentonite

Bentonite

Bentonite

(SP-SM)g - Poorly Graded Sand with Silt and Gravel

(SW)g - Well-Graded Sand with Gravel

SP - Poorly Graded Sand

SP-SM - Poorly Graded Sand with Silt

Bentonite - Bentonite

No Sample - No Sample

Shale - Shale

Topsoil - Topsoil

USGS 620 - Clay or Clay Shale

0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000

A

OMAHA DISTRICT

Notes:

1. Elevations in Project Datum.

2. Vertical exaggeration 10x.

3. View looking upstream to downstream.

4. Boring profiles projected to cross section line. R = right, L = left, CL = centerline.

5. Geologic contacts were generated using Surfer 16.0 and revised using professional judgment.

6. Groundwater measurements recorded 10/29/20. Reservoir at 1442.91.

7. See Plate B-1 for profile location.

1/

/2

Well Screen and Filter Pack Interval

1:

0H :1

:5 0V

Horizontal Scale in Feet

250.0 0.0 250.0 500.0 750.0

LITHOLOGY GRAPHICS

D E

S C

R

IP

T

IO

N

SHEET

M A

R K

A P

P R

(CL)s - Lean Clay with Sand

(CL)sg - Lean Clay with Sand and Gravel

(CL-ML)s - Silty Clay with Sand

(CL/CH)s - Lean to Fat Clay with Sand

CH - Fat Clay

CL - Lean Clay

CL-ML - Silty Clay

CL/CH - Lean to Fat Clay

OH - Organic Clay/Silt s(CL) - Sandy Lean Clay

S(CL/CH) - Sandy Lean to Fat Clay

SC - Clayey Sand

(ML)s - Silt with Sand

(SC)g - Clayey Sand with Gravel

ML - Silt

ML/CL - Clayey Silt s(ML) - Sandy Silt s(ML/CL) - Sandy Clayey Silt

Distance Along Baseline (ft)

1,360

1,380

1,400

1,420

1,440

1,460

1,480

1,500

1,520

1,540

1,560

SC-SM - Silty, Clayey Sand

(SM)g - Silty Sand with Gravel

(SP-SC)g - Poorly Graded Sand with Clay and Gravel (SW-SC)g - Well-Graded Sand with Clay and Gravel

SM - Silty Sand

SP-SC - Poorly Graded Sand with Clay

60/0.5

NUMBER

OF ENGINEERS

A P

P R

N W

O _F

E N

C E

_B _S

IZ

E

_S E

N S

IN

G

_Z O

N E

P

IP

E S

T E

M _D

A M

_P E

D .G

P J

U S

A C

E _N

W O

.G D

T

/2 5/

E le va tio n (f t)

N

D A

T E

D E

S C

R

IP

T

IO

N D

A T

E M

A R

K

U . S

A

R M

Y E

N G

IN

E

E R

D

IS

T R

IC

T

C O

R P

S O

F E

N G

IN

E

E R

S O

M A

H A

, N E

B R

A S

K A

D A

T E

D

C

B

US ARMY CORPS

D E

S

IG

N E

D B

Y

D W

N B

Y

C K

D B

Y

S O

LI

C

IT

A

T

IO

N N

O

C O

N T

R A

C T

N O

S

U B

M

IT

T E

D B

Y

F

IL

E N

A M

E

S

IZ

E

P

LO

T S

C A

LE

P

LO

T D

A T

E

F

IL

E N

U M

B E

R

1,580

1,600

1,620

1,640

1,660

A-A' B-B' C-C'

IDENTIFICATION

D D' x1

JA

M

B-5

P ip es te m D am

Ja m es to w n, N D

C ro ss S ec tio n D

-D

X

V er tic al

E xa gg er at io n

Glacio-Fluvial Sand

Pierre Shale

Glacial Till

S an d

G ra ve l

F in es

S an d

G ra ve l

F in es

60/0.3

NNN

ELEV. 1424.2

621 37

F in es

N

60/0.2

N

F in es

S an d

G ra ve l

60 3

LL PL

F in es

S an d

G ra ve l

LL PL

G ra ve l

N

1 42 56

G ra ve l

S an d

F in es

LL PL

N

Reservoir

ELEV. 1442.91

F in es

S an d

G ra ve l

60/0.5

S an d

60/0.2 60/0.2 60/0.4 60/0.4

LL PL

PZ19-15 (130' R)

BH19-06 (155' R)

ELEV. 1493.0

BH19-24 (20' R)

ELEV. 1495.2

BH-03 (CL)

ELEV. 1498.0

BH-04 (130' L)

ELEV. 1496.0

BH-07 (160' L)

ELEV. 1497.0

BH-13 (100' R)

ELEV. 1497.4L3 (55' L REMi)

ELEV. 1498.2

P-21 (230' R)

ELEV. 1495.6

PZ19-01 (175' R)

ELEV. 1494.1

1436.2 10/29/2020

1435.61 10/29/2020

1415.83 10/29/2020

Current Ground Surface

Bentonite sand layer

Bentonite

Vibrating Wire Tip

N W

O _F

E N

C E

_B _S

IZ

E

_S E

N S

IN

G

_Z O

N E

P

IP

E S

T E

M _D

A M

_P E

D .G

P J

U S

A C

E _N

W O

.G D

T

/2 5/

E le va tio n (f t)

Distance Along Baseline (ft)

D

C

B

A (CL)s - Lean Clay with Sand

NUMBER

OF ENGINEERS

A P

P R

D

A T

E D

E S

C R

IP

T

IO

N

US ARMY CORPS

D E

S

IG

N E

D B

Y

D W

N B

Y

C K

D B

Y

S O

LI

C

IT

A

T

IO

N N

O

D A

T E

M A

R K

U . S

A

R M

Y E

N G

IN

E

E R

D

IS

T R

IC

T

C O

N T

R A

C T

N O

S

U B

M

IT

T E

D B

Y

F

IL

E N

A M

E

S

IZ

E

P

LO

T S

C A

LE

M A

R K

A P

P R

(SW)g - Well-Graded Sand with Gravel

(SW-SM)g - Well-Graded Sand with Silt and Gravel

SP - Poorly Graded Sand

SP-SM - Poorly Graded Sand with Silt

SW - Well-Graded Sand

SW-SM - Well-Graded Sand with Silt

(GP)c - Poorly Graded Gravel with Cobbles

IDENTIFICATION

CH - Fat Clay

CL - Lean Clay

CL-ML - Silty Clay

CL/CH - Lean to Fat Clay g(CL) - Gravelly Lean Clay s(CH) - Sandy Fat Clay s(CL) - Sandy Lean Clay s(CL-ML) - Sandy Silty Lean Clay

S(CL/CH) - Sandy Lean to Fat Clay

SC - Clayey Sand

(ML/CL)s - Clayey Silt with Sand

(SC)g - Clayey Sand with Gravel

(SC-SM)g - Silty, Clayey Sand with Gravel

ML - Silt s(ML) - Sandy Silt

SC-SM - Silty, Clayey Sand

(SM)g - Silty Sand with Gravel (SP-SC)g - Poorly Graded Sand with Clay and Gravel

SM - Silty Sand

SP-SC - Poorly Graded Sand with Clay

(SP)g - Poorly Graded Sand with Gravel (SP-SM)g - Poorly Graded Sand with Silt and Gravel

C O

R P

S O

F E

N G

IN

E

E R

S O

M A

H A

, N E

B R

A S

K A

D A

T E

GP - Poorly Graded Gravel

Bentonite - Bentonite

Boulders/Cobbles - Boulders/Cobbles

COBBLES - Boulders and cobbles

No Sample - No Sample

Shale - Shale

Topsoil - Topsoil

USGS 620 - Clay or Clay Shale

P

LO

T D

A T

E

F

IL

E N

U M

B E

R

A-A' B-B' C-C'

E'E

Horizontal Scale in Feet

250.0 0.0 250.0 500.0 750.0

LITHOLOGY GRAPHICS

D E

S C

R

IP

T

IO

N

SHEET

OMAHA DISTRICT

1:

0H :1

:5 0V x1

JA

M

Well Screen and Filter Pack Interval

Limey Concretion

B-6

0 500 1,000 1,500 2,000 2,500 3,000 3,500 4,000 4,500 5,000 5,500 6,000

1/

/2

Notes:

1. Elevations in Project Datum.

2. Vertical exaggeration 10x.

3. View looking upstream to downstream.

4. Boring profiles projected to cross section line. R = right, L = left, CL = centerline.

5. Geologic contacts were generated using Surfer 16.0 and revised using professional judgment.

6. Groundwater measurements recorded 10/29/20. Reservoir at 1442.91.

7. See Plate B-1 for profile location.

1,360

1,380

1,400

1,420

1,440

1,460

1,480

1,500

1,520

1,540

1,560

1,580

1,600

1,620

1,640

1,660

Vibrating Wire Tip

P ip es te m D am

Ja m es to w n, N D

C ro ss S ec tio n E

-E

X

V er tic al

E xa gg er at io n

F in es

S an d

G ra ve l

S an d

0 1 99

60/1

N

G ra ve l

7 45 48

75241

0 91 8

60/0.9

60/0.9

60/1

60/0.8

F in es

LL

60/0.8

106/0.7

Pipestem Creek

60/0.2

109/0.8

Glacio-Fluvial Sand

Glacial Till

Glacial Till

Reservoir

ELEV. 1442.91

60/0.5

NF

in es

S an d

G ra ve l

Glacio-Fluvial Sand

Pipestem Creek Alluvium/ Slump Materials

N

Glacio-Fluvial Sand

Pierre Shale

60/0.5

NG

ra ve l

S an d

F in es

0 36 63

1 37 61

2 45 53

0 87 13

F in es

S an d

G ra ve l

0 84 16

PL N

N

LL PL N

ELEV. 1492.6

LL

PZ19-02 (Lower Glacio-Fluvial Sands) PZ19-03 (Upper Glacio-Fluvial Sands)

100' L

PL

68014

PZ19-16

(70' R) PZ19-17

(45' L)

BH20-01 (70' R)

ELEV. 1491.3

ELEV. 1411.4

ELEV. 1412.0

BH-01 (45' L)

ELEV. 1497.0

ELEV. 1495.0

BH-05 (200' L)BH-06 (25' R)

ELEV. 1495.8

ELEV. 1498.0

BH-09 (30' L)

P-27 (295' L)

ELEV. 1496.3

ELEV. 1496.0

P-28 (115' L)S-1 (175' R)

ELEV. 1495.9

ELEV. 1506.7

S-9 (185' L)

1437.97 10/29/2020

1408.60

10/29/2020

1423.64 (during drilling)

1435.16 10/29/2020

PZ19-02

1439.86 10/29/2020 1436.20

10/29/2020

PZ19-03

1415.09

10/29/2020

Current Ground Surface

Stepped Chute Structure (Approximate Location)

Stilling Basin (Approximate Location)

Bentonite

Bentonite

Bentonite

Bentonites (2)

US ARMY CORPS

D E

S

IG

N E

D B

Y

D W

N B

Y

C K

D B

Y

S O

LI

C

IT

A

T

IO

N N

O

Reservoir

ELEV. 1442.91

1,400

1,420

1,440

1,460

D A

T E

M A

R K

U . S

A

R M

Y E

N G

IN

E

E R

D

IS

T R

IC

T

1/

/2

A-A' B-B' C-C'

NUMBER

OF ENGINEERS

A P

P R

D

A T

E D

E S

C R

IP

T

IO

N

F'F

D

C

B

A

1,480

1,500

1,520

1,540

1,560

1,580

1,600

1,620

1,640

1,660

0 500 1,000 1,500 2,000 2,500 3,000

IDENTIFICATION

N W

O _F

E N

C E

_B _S

IZ

E

_S E

N S

IN

G

_Z O

N E

P

IP

E S

T E

M _D

A M

_P E

D .G

P J

U S

A C

E _N

W O

.G D

T

/1 1/

E le va tio n (f t)

Distance Along Baseline (ft)

C O

N T

R A

C T

N O

S

U B

M

IT

T E

D B

Y

F

IL

E N

A M

E

S

IZ

E

P

LO

T S

C A

LE

P

LO

T D

A T

E

F

IL

E N

U M

B E

R

M A

R K

A P

P R

C O

R P

S O

F E

N G

IN

E

E R

S O

M A

H A

, N E

B R

A S

K A

D A

T E

OMAHA DISTRICT

CL - Lean Clay g(CL) - Gravelly Lean Clay s(CH) - Sandy Fat Clay

(SP-SM)g - Poorly Graded Sand with Silt and Gravel

(SW)g - Well-Graded Sand with Gravel

(SW-SM)g - Well-Graded Sand with Silt and Gravel

(SP)g - Poorly Graded Sand with Gravel Hardpan

CL/CH - Lean to Fat Clay

(ML/CL)s - Clayey Silt with Sand

(SC-SM)g - Silty, Clayey Sand with Gravel

ML - Silt

(SP-SC)g - Poorly Graded Sand with Clay and Gravel

GM - Silty Gravel

SP - Poorly Graded Sand

SP-SM - Poorly Graded Sand with Silt

SW - Well-Graded Sand

GP - Poorly Graded Gravel

COBBLES - Boulders and cobbles

No Sample - No Sample

Shale - Shale

1:

0H :1

:5 0V x1

JA

M

B-7

Well Screen and Filter Pack Interval

Horizontal Scale in Feet

250.0 0.0 250.0 500.0 750.0

D E

S C

R

IP

T

IO

N

SHEET

LITHOLOGY GRAPHICS

(CH)s - Fat Clay with Sand

(CL)s - Lean Clay with Sand s(MH) - Sandy Elastic Silt GP-GC - Poorly Graded Gravel with Clay

(CL-ML)s - Silty Clay with Sand

(CL/CH)s - Lean to Fat Clay with Sand

CH - Fat Clay

CL-ML - Silty Clay s(CL) - Sandy Lean Clay s(CL-ML) - Sandy Silty Lean Clay

S(CL/CH) - Sandy Lean to Fat Clay

SC - Clayey Sand

(SC)g - Clayey Sand with Gravel s(ML) - Sandy Silt

SC-SM - Silty, Clayey Sand (GP-GC)s - Poorly Graded Gravel with Clay and Sand

SM - Silty Sand

SP-SC - Poorly Graded Sand with Clay

SW-SC - Well-Graded Sand with Clay

1,360

1,380

3,500 4,000 4,500 5,000 5,500 6,000

Notes:

1. Elevations in Project Datum.

2. Vertical exaggeration 10x.

3. View looking upstream to downstream.

4. Boring profiles projected to cross section line. R = right, L = left, CL = centerline.

5. Geologic contacts were generated using Surfer 16.0 and revised using professional judgment.

6. Groundwater measurements recorded 10/29/20. Reservoir at 1442.91.

7. See Plate B-1 for profile location.

LL

P ip es te m D am

Ja m es to w n, N D

C ro ss S ec tio n F

-F

X

V er tic al

E xa gg er at io n

Pipestem Creek

Pipestem Creek Alluvium/ Slump MaterialsPZ19-20 (15' R)

ELEV. 1418.3

Glacial Till

Pierre Shale

Glacio-Fluvial Sand

Glacial Till

Glacio-Fluvial Sand

LL

F in es

S an d

G ra ve l

BH19-08 (220' R)

ELEV. 1491.4

PL

60/0.4

N

54 5

60/0.2

N

BH-10 (60' R)

ELEV. 1495.5

F in es

S an d

G ra ve l

ELEV. 1498.0

BH-12 (85' R)

52/0.8

60/0.3

N

F in es

S an d

G ra ve l

60 94

P-19 (185' L)

ELEV. 1459.0

P-29 (170' L)

ELEV. 1507.6

60/0.4

LL PL N

1 2

F in es

S an d

G ra ve l

ELEV. 1492.5

PZ19-04 (Lower Glacio-Fluvial Sands) PZ19-05 (Upper Glacio-Fluvial Sands)

70' L

60/0.2

N

60/0.9

PL

ELEV. 1509.8

S-18 (60' R)

1414.39 10/21/2020

1437.83 10/29/2020 1436.06

10/29/2020

PZ19-04

1436.28 10/29/2020

PZ19-05 1432.25

10/29/2020

Current Ground Surface

Stepped Chute Structure (Approximate Location)

Stiling Basin (Approximate Location)

Bentonite

Appendix B Optical Televiewer Data and Plots (FIPP)

All directions are with respect to Magnetic North.

Stereonet Diagram – Schmidt Projection Televiewer Image Features

USACE

Pipestem 2 Pipestem

14 October 2020

USACE

Pipestem 2

Rose Diagram – Dip Directions

USACE

Pipestem 2

Rose Diagram – Dip Angles

USACE

Pipestem 2

Orientation Summary Table

USACE

Pipestem

Pipestem 2 14 October 2020

Feature Depth Depth Dip Dip Feature

No. (meters) (feet) Direction Angle Rank

(degrees) (degrees) (0 to 5)

1 2.24 7.3 50 41 3

2 2.24 7.4 284 32 3

3 2.24 7.4 175 34 3

4 2.79 9.1 300 36 1

5 2.88 9.5 350 76 1

6 2.99 9.8 323 75 1

7 3.00 9.8 312 46 1

8 3.01 9.9 273 68 1

9 3.19 10.5 110 12 1

10 3.77 12.4 296 67 1

11 3.79 12.4 81 42 1

12 3.90 12.8 85 79 1

13 3.96 13.0 207 77 1

14 4.36 14.3 115 16 1

15 4.43 14.5 296 70 1

16 4.43 14.5 147 64 1

17 4.92 16.1 320 68 0

18 5.70 18.7 207 11 1

19 5.75 18.9 200 19 0

20 5.77 18.9 205 11 0

21 6.28 20.6 202 79 0

22 6.93 22.7 52 8 0

23 7.02 23.0 94 6 0

24 7.18 23.6 327 74 0

25 7.19 23.6 228 9 0

26 7.52 24.7 161 5 0

27 7.95 26.1 89 57 0

28 8.03 26.3 257 55 0

29 8.30 27.2 36 4 0

30 8.58 28.1 169 26 1

31 8.58 28.2 283 22 1

32 8.60 28.2 55 11 0

33 10.10 33.1 292 85 0

34 10.87 35.7 194 8 0

35 11.02 36.1 299 85 0

36 12.32 40.4 26 74 1

37 12.71 41.7 299 8 0

USACE

Pipestem

Pipestem 2 14 October 2020

Feature Depth Depth Dip Dip Feature

No. (meters) (feet) Direction Angle Rank

(degrees) (degrees) (0 to 5)

38 13.12 43.0 250 68 0

39 15.28 50.1 303 13 0

40 15.43 50.6 160 6 0

41 15.55 51.0 160 9 0

42 15.57 51.1 115 8 1

43 15.63 51.3 305 69 0

44 15.80 51.9 224 77 0

45 16.48 54.1 33 81 0

46 16.58 54.4 70 41 2

47 16.62 54.5 48 42 3

48 16.65 54.6 210 53 3 borehole geophysics / hydrophysics

COMPANY:

DATE LOGGED:

PROJECT:

WELL:

COMMENTS:

Pipestem 2 www.colog.com

Optical Televiewer

14 October 2020

USACE Pipestem Phone: (303) 279-0171, Fax: (303) 278-0135

810 Quail St., Suite E, Lakewood, CO 80215

Colog, Inc.

Televiewer data collected by client, COLOG asked to perform data processing.

Borehole Diameter = 3.78" HQ

Depth

1ft:10ft

Optical Image-NM

0° 0°180°90° 270°

Projections

0° 0°180°90° 270°

Tadpoles

0 90

Depth

1ft:10ft

Optical Image-NM

0° 0°180°90° 270°

Projections

0° 0°180°90° 270°

Tadpoles

0 90

USACE

Pipestem 20

USACE

Pipestem 20

Rose Diagram – Dip Directions

USACE

Pipestem 20

Rose Diagram – Dip Angles

USACE

Pipestem 20

USACE

Pipestem

Pipestem 20 14 October 2020

Feature Depth Depth Dip Dip Feature

No. (meters) (feet) Direction Angle Rank

(degrees) (degrees) (0 to 5)

1 24.07 79.0 247 13 4

2 24.09 79.0 316 72 3

3 24.16 79.3 24 26 4

4 24.20 79.4 85 42 1

5 24.65 80.9 332 75 1

6 24.73 81.1 271 81 1

7 24.81 81.4 6 81 1

8 25.04 82.2 179 46 1

9 25.08 82.3 167 78 1

10 25.24 82.8 71 76 1

11 25.46 83.5 113 82 2

12 25.63 84.1 263 78 2

13 25.89 85.0 109 65 1

14 26.00 85.3 116 60 1

15 26.08 85.6 323 79 1

16 26.30 86.3 276 71 1

17 26.39 86.6 107 53 2

18 26.53 87.0 200 72 1

19 26.58 87.2 269 44 1

20 26.73 87.7 357 74 1

21 26.80 87.9 129 32 1

22 27.01 88.6 77 21 1

23 27.07 88.8 29 75 2

24 27.18 89.2 185 75 1

25 27.47 90.1 290 83 1

26 27.47 90.1 347 87 1

27 27.54 90.3 65 60 1

28 27.59 90.5 273 79 2

29 27.80 91.2 271 82 3

30 27.85 91.4 92 33 1

31 27.97 91.8 83 83 2

32 28.03 92.0 221 28 1

33 28.18 92.5 108 58 1

34 28.27 92.8 223 80 2

35 28.30 92.9 213 8 1

36 28.70 94.2 191 75 2

37 28.76 94.4 227 67 2

USACE

Pipestem

Pipestem 20 14 October 2020

Feature Depth Depth Dip Dip Feature

No. (meters) (feet) Direction Angle Rank

(degrees) (degrees) (0 to 5)

38 28.88 94.7 209 71 2

39…