1982_Project Info-MOD_Slope Stability_20150513

(> DUKE
ENERGY
May 13, 2015
VIA ELECTRONIC MAIL AND U.S. MAIL
Mr. Steven M. McEvoy, PE
State Dam Safety Engineer
Department of Environment and Natural Resources
Division of Land Resources - Land Quality
512 North Salisbury Street
Raleigh, North Carolina 27604-1148
John Einitsky
Senior Vice President Ash Basin Strategy
400 South Tryon Street
P.O. Box 1321, ST031
Charlotte, NC 28202
Phone: [phone]
Email: John. Elnitsky@duk"nergy.com
ECEI'
NAY 1 - 2015
Lo4hlb W SECS
RE: Submittal of Engineered Plans for Excavation and Stabilization for the Following:
Asheville Plant 1982 Ash Basin Dam
BUNCO-089
Buncombe County, NC
Dear Mr. McEvoy:
Duke Energy Progress, Inc. ("Duke Energy") hereby submits for review and approval
proposed ash excavation and stabilization at the facility noted above. The ash remaining along
the upstream slope of the facility must be excavated to achieve full removal of coal combustion
material in the 1982 Basin required by the Coal Ash Management Act of 2014. Information
regarding the excavation, sequencing of activities and stabilization of the dam are provided in the
attached report and plans prepared by Charah and GeoTrack Technologies, Inc.. This work will
be completed under the supervision of the registered professional engineer noted, and a
completion report will be submitted following installation. It is requested that any applicable 10-
day notification requirement be waived such that activities may start upon approval. We look
forward to receiving approval of excavation associated with the enclosed plans.
Duke Energy is committed to excellent environmental stewardship and to cooperation
with the Division regarding the operation, maintenance, safety, and integrity of all of its ash
basins, dams, and associated systems in North Carolina. We look forward to continuing to work
with you regarding such issues and to ensure that Duke Energy's dams are maintained in good
condition.
ff�,C v

Page 2of2
May 13, 2015
If you have any questions or need clarification regarding the information provided, feel
free to contact John Toepfer [e-mail] or [phone] at your
convenience.
submitted,
Bohn Elnits`ky-----
Senior Vice President
cc: Garry Miller
Garry Whisnant
Laurie Moorhead
Steadman Sugg
Harry Sideris
Dan Kemp
Jim Wells
Richard Baker
Shannon Langley
Ed Sullivan
John Toepfer
Giorgina Franklin
Claudia Prado

ECEI VE
MA Y 10
?015
EOTRACK PeiR
QU
Technologies, Inc. wii�SCC7/01V
3620 Pelham Road, PMB #292 Phone: [phone]
Greenville, SC 29615-5044 FAX: [phone]
February 19, 2015 (Revised)
Charah, Inc.
P.O. Box 287
Belmont, NC 28012
Attn: Mr. Norman Divers, III
Re: Slope Stability Analysis
Former 1982 Ash Pond Dam, State ID: BUNCO-089
Duke Asheville Steam Station
Asheville, NC
GeoTrack Project No. 12-3004C-N
Ladies and Gentlemen:
GeoTrack Technologies, Inc. has completed a slope stability analysis of the upstream slope of
the 1982 earthen dam, and we present the results herein. The analysis was performed as
requested during meetings with Mr. Divers of Charah on October 22, 2014 and December 17,
2014. The purpose of the work was to evaluate the stability of the 1982 Ash Pond dam
(embankment) following removal of the remaining ash on the upstream (north) slope. This
report presents our procedures, assumptions, findings and conclusions.
Proiect Information: The 1982 dam formerly supported a CCB settling and disposal pond that
has been removed from service. The CCB has been progressively excavated from the pond
interior, and the current CCB is estimated to be 40 to 50 feet below the dam crest. During
excavation, the water within the CCB is removed by pumping from temporary sumps. The
pumps are operated on a continuous basis, as needed, to maintain water levels below the
excavation base. In accordance with previous recommendations and instructions, a zone of CCB
has remained on the dam slope, as a buffer against damage to the dam from the removal process.
The remaining CCB and water (estimated to be about 30 to 40 feet deep) is being removed from
the 1982 pond by Charah, and they are currently making plans to remove the remaining veneer
of CCB from the upstream slope of the earthen dam. The existing dam geometry and estimated
soil strength parameters were obtained from various drawings provided by Charah and a
previously issued report by GeoTrack as follows:

Slope Stability Analysis, 1982 Ash Pond Dam GeoTrack Project No. 12-3004C-N
Duke Asheville Steam Station, Asheville, NC Revised February 18, 2015
• Asheville S.E.P. Ash Pond Expansion Sections, dated March 14, 1981.
• Asheville S.E.P. Ash Pond Expansion Typical Sections & Details, dated March
19, 1981.
• 1982 Ash Pond Dam Plan and Profile, dated May 2007, by MACTEC.
• Piezometer and Soil Boring Location Map, dated April, 18, 2007, by Golder
Associates.
• Dewatering / Excavation Plan (1.0), dated June 17, 2013, by Franklin S. Craig.
• GeoTrack Preliminary Stability Analysis for Proposed Stilling Basin Report,
dated December 17, 2012.
The above dam plans and explorations were obtained by GeoTrack from internet research
conducted as part of the previous Preliminary Stability Analysis for Proposed Stilling Basin.
The information was obtained from an appendix to the Coal Combustion Waste Impoundment
Dam Assessment Report, dated June 2009, by Dewberry and Davis.
After completion and initial submission of this stability analysis, on January 2, 2015, we were
provided a report by AMEC titled: Phase 2 Reconstitution of Ash Pond Designs, Final Report
Submittal, Revision A, dated December 31, 2014. That report was provided. Our review of that
report and significance to this analysis are discussed in the AMEC Report Review section on
page 4.
Based on the provided information, the crest of the dam is approximately 15 feet wide with a
maximum elevation of about 2165 feet. Not including the remaining CCB, the earthen dam has
an upstream slope inclination of 2H:1 V (horizontal to vertical) and a downstream inclination of
2.5H:1 V. At the location of a former stream channel, the upstream slope is approximately 95
feet high based on a minimum toe elevation of 2070 feet, and the downstream slope is
approximately 103 feet high based on a minimum toe elevation of 2062 feet.
The available plans indicate that the 1982 earthen dam was constructed of a single (homogenous)
zone of compacted sandy silt over natural dense residual soils and/or partially weathered rock. A
downstream sand blanket drain extends approximately 125 feet horizontally from the toe into the
base of the dam (distance equals B/2, with B equaling the horizontal distance of the toe to the
centerline of the dam). The upper 15 feet of the upstream slope of the dam is also lined with a
roughly 2-foot thick layer of crushed rock and rip rap to provide wave protection.
Stability Analysis Description: CCB excavation in the pond results in two stabilizing
influences on the 1982 dam. First, removal of the CCB against the upstream face removes the
primary driving force that would affect dam stability (loose, saturated CCB) of the downstream
slope. Second, the dewatering, and continued internal seepage toward the internal toe drain, will
dewater the dam and increase the internal stability. The CCB removal will render the dam to
essentially a free-standing earthen embankment with exterior loading limited only to traffic on
the slope crest. Our analyses only included the upstream slope, since it is steeper than the
downstream slope and nearly as high. Also, the downstream slope will not be disturbed or
modified by Charah at this time. Furthermore, the downstream face has been analyzed by
AMEC and others for previous service conditions and future use.
Page 2

Slope Stability Analysis, 1982 Ash Pond Dam GeoTrack Project No. 12-3004C-N
Duke Asheville Steam Station, Asheville, NC Revised February 18, 2015
The future geometry of the slope was modeled using slope stability analysis software (Slope/W)
that allows varying soil and slope conditions to be evaluated by randomly -generated failure
surfaces. The analyses computed theoretical factors of safety, using four different methods
(Spencer, Morgenstern and Price, Bishop, and Janbu) for various assumed failure surfaces
through the soil layers for the potential load conditions.
The modeled slope surface geometry and subsurface soil zones were estimated as previously
described. The modeled soil zones include well compacted existing fill and high consistency
residual soils, which transition with depth to partially weathered rock (PWR) and mass rock.
The CCB was not modelled, since it will be completely removed from the slope and pond area.
The on -going excavation process results in a constant reduction of water elevations within the
dam. The rate of excavation and effectiveness of the dewatering methods prevent a significantly
higher water level within the dam. A 20-foot high mound of water was arbitrarily modelled near
the core of the dam that is assumed to exit the upstream toe of the dam at the dam foundation and
the downstream toe through the previously described blanket drain.
Slope stability analyses are heavily dependent on soil strength factors. The following soil
strength properties were obtained from literature and estimated by GeoTrack based on our
experience with similar soil conditions and our knowledge of the embankment.
Table 1. Stability Strength Parameters
Estimated Moist
Estimated Effective
Estimated Effective
Material
Unit Weight (pcf)
Phi (O')
Cohesion (c') (psf)
Angle (Degrees)
Compacted Fill
120
30
370
Residual Soils (Saprolite)
130
32
400
Partially Weathered Rock
135
45
10,000
Rip Rap / Crushed Stone
100
40
0
The slope was analyzed under both static and seismic (earthquake forces) conditions.
Earthquake forces were considered by performing pseudo -static analyses. To simulate the
seismic forces, the peak ground acceleration (PGA) for the area was obtained from the North
Carolina Seismic Hazard Map 2008 found at the USGS website for a return period of 2,500 year
(2 percent probability in 50 years). The peak ground acceleration (PGA) for the site is 0.1595
times the acceleration of gravity (g). This value was then increased by 1.2 based on the slope
being situated on material assessed to have a Seismic Site Class C. The resulting PGA of
0.1914g was then rounded up to 0.2g and used as the horizontal earthquake force in the
SLOPE/W program. To remain conservative in our approach, a reduction factor for the ratio of
the depth to failure surface divided by the depth to rock was not utilized. The static and seismic
conditions were also modelled with an aerial load of 250 pounds per square foot over the crest of
the dam to conservatively account for the possible future construction of a road and potential
vehicular traffic on the embankment.
Page 3

Slope Stability Analysis, 1982 Ash Pond Dam GeoTrack Project No. 12-3004C-N
Duke Asheville Steam Station, Asheville, NC Revised February 18 2015
Results and Conclusions: The slope stability software was used to randomly generate circular
failure surfaces through the subsurface soil zones under static and seismic conditions. The
failure surfaces resulting in the lowest computed factors of safety are listed below and shown in
the attached figures (Spencer results) for the analyzed slope static and seismic conditions along
with the input data (Slope/W Analysis Report) for both the static and seismic conditions. The
selected geometric section is assessed to be the most critical slope condition, and is therefore
representative of the overall stability of the dam embankment.
Table 2. Generated Slope Stability Safety Factors
Method
Static Condition
Seismic Condition (0.2g)
Spencer
1.72
1.13
Morgenstern and Price
1.72
1.13
Bishop
1.72
1.13
Janbu
1.57
1.01
Factors of safety greater that one indicate the resistive forces are theoretically greater than the
driving forces. Nationally recognized geotechnical texts and other publications and standard
engineering practice indicate that factors of safety exceeding 1.5 are acceptable for excavation
and fill slopes under long-term, sustained static loading conditions. Factors of safety greater than
one are generally considered acceptable under extreme loading conditions, such as earthquakes,
due to the transient nature of the loading conditions and the low statistical occurrence interval.
The results from the Janbu method appear to be much more conservative than the other three
methods. Also, we conservatively selected the earthquake loading condition of 0.2g. Thus, we
assess the results of the analyses to indicate that the overall slope stability of the dam are within
satisfactory ranges under static and seismic conditions based on the input data.
AMEC Report Review: We were provided the Phase 2 Reconstitution of Ash Pond Designs,
Final Report Submittal, Revision A, dated December 31, 2014 by AMEC. Information provided
to us included the report text and Appendices A through H, excluding Appendix B. The report
included a comprehensive review of existing subsurface data relative to the 1982 dam. The
report also summarizes additional exploration and analyses performed by AMEC.
Section 3.3.1 of the AMEC report lists available borings and explorations performed at the
Asheville Plant. Most of the listed explorations were performed within the 1964 Pond, and are
not pertinent to this matter. AMEC referred to two sets of previous data: A 2006 exploration by
Golder and Associates included borings and piezometers in the 1982 Dam and separator dike,
and borings performed by Froehling and Robertson (F&R) in 1980 before construction of the
1982 Dam. The F&R report was not made available to GeoTrack, and AMEC indicated it is not
available. AMEC stated that geologic profiles on CP&L Drawing D-0666 included some of the
Page 4

Slope Stability Analysis, 1982 Ash Pond Dam GeoTrack Project No. 12-3004C-N
Duke Asheville Steam Station, Asheville, NC Revised February 18, 2015
F&R Boring results. That drawing, and the Golder information, was part of the information
listed on page 2 which was obtained and reviewed by GeoTrack as part of our stability analysis
discussed herein, and the analyses summarized in the report dated December 17, 2012.
In the recent AMEC analysis, soil test borings, piezometers, electronic cone penetration
soundings, and laboratory testing were performed for the 1982 Dam. The following were noted
to be pertinent to the GeoTrack analyses, based on our review of the AMEC report:
• Two clusters of borings and cone penetrometer tests were performed through the 1982
Dam embankment. GeoTrack could not identify the cone penetration logs in the AMEC
report; however, the boring results indicated favorable soil conditions consistent with
previously available information.
• AMEC performed laboratory strength tests on three samples collected from the 1982
embankment. Those results were variable, but indicated favorable strength conditions
consistent with the boring results and strength analyses reported in the previous literature.
• In their slope stability analyses, AMEC utilized strength parameters similar to those
reported previously, which were assessed to be conservative relative to the more recent
data. The strength parameters were very similar to those used by GeoTrack above.
• AMEC's calculated ground acceleration for use in the earthquake analyses were identical
to the acceleration estimated and used by GeoTrack (0.2g).
• Water levels in the embankment interior measured by AMEC were lower than assumed
by GeoTrack; therefore, GeoTrack's assumptions were conservative.
Based on our review of the AMEC information, the analyses completed by GeoTrack and
summarized above are assessed to be conservative, but representative of actual conditions. No
further refinement of the analyses are warranted.
Excavation Sequencing and Considerations: We understand excavation of the remaining CCB
from the slope face will be performed with large tracked excavators with extended reaches.
Spotters will be present on the ground to assess when the CCB is penetrated and the original dam
slope is exposed. In the context of the entire embankment volume, minor disturbance to the
surface soils will not measurably reduce the internal dam stability indicated above. We
understand the exposed surface will be compacted and covered with approximately one foot of
compacted fill. We recommend that the fill be compacted to at least 95 percent of the soil's
maximum dry density obtained from the standard Proctor compaction test (ASTM D-698). This
compaction can likely be achieved with track -hoes equipped with trench roller attachments
and/or large tracked equipment traversing up and down the slope face.
Following re -compaction of the slope face, we understand a layer of topsoil will be placed and
grass seed applied to protect the surface of the slope. An erosion control mat, should be placed
and maintained over the topsoil and grass seed until the grass takes hold.
Page 5

Slope Stability Analysis, 1982 Ash Pond Dam GeoTrack Project No. 12-3004C-N
Duke Asheville Steam Station, Asheville, NC Revised February 18 2015
Closing: GeoTrack is pleased to be of continued service to you on this project. Please call if
you have any questions concerning the slope stability analysis or if we may provide additional
assistance.
Respectfully submitted,
GeoTrack Technologies, Inc.
NC Firm No. C-2426
Kenneth W. Weinel, P.E.
Senior Engineer
NC Registration No. 21531
Senior Engineer
NC Registration No. 17088
Attachments: 1) Static Condition Figure and Slope/W Analysis Report
2) Seismic Condition Figure and Slope/W Analysis Report
Page 6

Asheville Steam Plant
1982 Upstream Slope - Static Condition
_. A 7_ 100 1Z5 150 175 2D0 225 250 ZT5 30D 3Z6 350 375 400 425 4W 475 ".00 525 550 575 500
Distance (Feet)

SLOPE/W Analysis Page 1 of 6
SLOPE/W Analysis
Report generated using Geostudio 2012. Copyright © 1991-2014 GEO-SLOPE International Ltd.
File Information
Created By: Ken Weinel
Last Edited By: Ken Weinel
Revision Number: 58
File Version: 8.3
Tool Version: 8.13.1.9253
Date: 12/23/2014
Time: 1:11:01 PM
File Name: 1982 Dam Slope Static.gsz
Directory: S:\PROJECTS\2012 PROJECTS\12-3004C Asheville Pond CCB Exploration\1982 Dam Slope Eval\
Last Solved Date: 12/23/2014
Last Solved Time: 4:08:47 PM
Project Settings
Length(L) Units: Feet
Time(t) Units: Seconds
Force(F) Units: Pounds
Pressure(p) Units: psf
Strength Units: psf
Unit Weight of Water: 62.4 pcf
View: 2D
Element Thickness: 1
Analysis Settings
SLOPE/W Analysis
Kind: SLOPE/W
Method: Spencer
Settings
Lambda
Lambda 1: -1
Lambda 2: -0.8
Lambda 3: -0.6
Lambda 4: -0.4
Lambda 5: -0.2
Lambda 6: 0
Lambda 7: 0.2
Lambda 8: 0.4
Lambda 9: 0.6
Lambda 10: 0.8
Lambda 11: 1
PWP Conditions Source: Piezometric Line
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SLOPE/W Analysis
Page 2 of 6
Apply Phreatic Correction: No
Use Staged Rapid Drawdown: No
Slip Surface
Direction of movement: Right to Left
Use Passive Mode: No
Slip Surface Option: Entry and Exit
Critical slip surfaces saved: 1
Optimize Critical Slip Surface Location: No
Tension Crack
Tension Crack Option: (none)
F of S Distribution
F of S Calculation Option: Constant
Advanced
Number of Slices: 30
F of S Tolerance: 0.001
Minimum Slip Surface Depth: 0.1 ft
Optimization Maximum Iterations: 2,000
Optimization Convergence Tolerance: 1e-007
Starting Optimization Points: 8
Ending Optimization Points: 16
Complete Passes per Insertion: 1
Driving Side Maximum Convex Angle: 5 °
Resisting Side Maximum Convex Angle: 1 °
Materials
Compacted Fill
Model: Mohr -Coulomb
Unit Weight: 120 pcf
Cohesion': 370 psf
Phi': 30 °
Phi-B: 0 °
Pore Water Pressure
Piezometric Line: 1
Residuum
Model: Mohr -Coulomb
Unit Weight: 130 pcf
Cohesion': 400 psf
Phi': 32 °
Phi-B: 0 °
Pore Water Pressure
Piezometric Line: 1
Rip Rap and Crushed Stone
Model: Mohr -Coulomb
Unit Weight: 100 pcf
Cohesion': 0 psf
Phi': 40 °
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.SLOPE/W Analysis
Page 3 of 6
Phi-B: 0 °
Pore Water Pressure
Piezometric Line: 1
Slip Surface Entry and Exit
Left Projection: Range
Left -Zone Left Coordinate: (14.91251, 2,070) ft
Left -Zone Right Coordinate: (156, 2,118) ft
Left -Zone Increment: 4
Right Projection: Range
Right -Zone Left Coordinate: (212.19202, 2,146.096) ft
Right -Zone Right Coordinate: (341.39806, 2,134.5) ft
Right -Zone Increment: 4
Radius Increments: 4
Slip Surface Limits
Left Coordinate: (0, 2,070) ft
Right Coordinate: (583, 2,057) ft
Piezometric Lines
Piezometric Line 1
Coordinates
X (ft)
Y (ft)
Coordinate 1
0
2,070
Coordinate 2
60
2,070
Coordinate 3
150
2,080
Coordinate 4
250
2,090
Coordinate 5
400
2,064
Coordinate 6
523
2,062
Coordinate 7
575
2,062
Surcharge Loads
Surcharge Load 1
Surcharge (Unit Weight): 50 pcf
Direction: Vertical
Coordinates
X (ft)
Y (ft)
250
2,170
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•SLOPE/W Analysis
Page 4 of 6
1265 12,170
Seismic Coefficients
Horz Seismic Coef.: 0
Points
X (ft)
Y (ft)
Point 1
0
2,070
Point 2
60
2,070
Point 3
220
2,150
Point 4
250
2,165
Point 5
262
2,165
Point 6
265
2,165
Point 7
523
2,062
Point 8
583
2,057
Point 9
222
2,150
Point 10
250
2,163
Point 11
251
2,164.5
Point 12
253
2,164.5
Point 13
262
2,164.5
Point 14
583
2,030
Point 15
0
2,030
Regions
Material
Points
Area (ft2)
Region 1
Compacted Fill
2,3,9,10,11,12,13,5,6,7
23,475
Region 2
Rip Rap and Crushed Stone
3,4,5,13,12,11,10,9
49.75
Region 3
Residuum
1,2,7,8,14,15
20,838
Current Slip Surface
Slip Surface: 33
F of S: 1.72
Volume: 4,440.1384 ft'
Weight: 532,935.97 Ibs
Resisting Moment: 67,617,159 Ibs-ft
Activating Moment: 39,381,406 Ibs-ft
Resisting Force: 322,467.94 Ibs
Activating Force: 187,816.53 Ibs
F of S Rank: 1
Exit: (53.017198, 2,070) ft
Entry: (243.39229, 2,161.6961) ft
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,SLOPE/W Analysis
Page 5 of 6
Radius: 184.75535 ft
Center: (82.433821, 2,252.3985) ft
Slip Slices
X (ft)
Y (ft)
PWP (psf)
Base Normal
Frictional
Cohesive
Stress (psf)
Strength (psf)
Strength (psf)
Slice
56.508599
2,069.5051
30.882241
250.40264
137.17157
400
1
Slice
2
63.311453
2,068.6655
106.2298
610.15989
314.89047
400
Slice
69.934358
2,068.0963
187.66858
1,150.4848
601.63433
400
3
Slice
76.557263
2,067.7663
254.17831
1,622.6618
855.12342
400
4
Slice
83.180168
2,067.6743
305.83911
2,032.8547
1,079.1591
400
5
Slice
6
89 803074
2,067.8199
342.67322
2,386.0963
1,276.8725
400
Slice
96.425979
2,068.2037
364.64541
2,686.5182
1,450.8672
400
7
Slice
103.04888
2,068.8271
371.66238
2,937.5231
1,603.3277
400
8
Slice
9
109.36351
2,069.6415
364.62518
3,114.0781
1,587.3974
370
Slice
115.36985
2,070.6282
344.69991
3,276.4763
1,692.6619
370
10
Slice
121.37619
2,071.82
311.97519
3,405.6074
1,786.1094
370
11
Slice
127.38253
2,073.221
266.1953
3,502.484
1,868.4721
370
12
Slice
13
133.38887
2,074.8362
207.05083
3,567.9129
1,940.3946
370
Slice
139.39521
2,076.6715
134.17279
3,602.5122
2,002.4467
370
14
Slice
145.40155
2,078.7339
47.12516
3,606.7237
2,055.1352
370
15
Slice
149.20236
2,080.1319
-13.761049
3,596.8087
2,076.6185
370
16
Slice
153.18182
2,081.7603
-89.986123
3,567.2102
2,059.5298
370
17
Slice
159.54545
2,084.5412
-223.805
3,500.6057
2,021.0756
370
18
Slice
165.90909
2,087.6147
-375.88338
3,403.8754
1,965.2284
370
19
Slice
172.27273
2,090.9976
-547.26665
3,277.3948
1,892.2047
370
20
Slice
178.63636
2,094.7098
-739.20025 3,121.4072
1,802.1453
370
21
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SLOPE/W Analysis
Page 6 of 6
Slice
185
2,098.7753
-953.17799
2,936.0328
1,695.1194
370
22
Slice
191.36364
2,103.223
2,721.2767
1,571.1298
370
23
1,191.0078
Slice
197 72727
2,108.0885
2,477.0396
1,430.1195
370
24
1,454.9028
Slice
204.09091
2,113.4157
2,203.134
1,271.98
370
25
1,747.6121
Slice
210.45455
2,119.2604
1,899.3128
1,096.5687
370
26
2,072.6117
Slice
216.81818
2,125.6946
1,565.3227
903.73948
370
27
2,434.3975
Slice
221
2,130.2033
1,330.0428
767.90056
370
28
2,689.6437
Slice
225.33562
2,135.4118
1,057.4294
610.50715
370
29
2,987.6001
Slice
232.00685
2,144.0929
630.78176
364.18202
370
30
3,487.6729
Slice
238.67809
2,153.9958
173.48752
100.16307
370
31
4,063.9847
Slice
242.703
2,160.4941
36.274993
30.438333
0
32
4,444.3658
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W
Asheville Steam Plant
1982 Upstream Slope - Seismic Condition
_.---0 25 50 75 100 125 150 175 200 225 2F0 303 ,__ 3'0 3-It 403 42' 4F0 t "00 5=3 _7_ 500
Distance (Feet)

SLOPE/W Analysis Page 1 of 4
SLOPE/W Analysis
Report generated using GeoStudio 2012. Copyright © 1991-2014 GEO-SLOPE International Ltd.
File Information
Created By: Ken Weinel
Last Edited By: Ken Weinel
Revision Number: 62
File Version: 8.3
Tool Version: 8.13.1.9253
Date:12/23/2014
Time: 4:06:51 PM
File Name: 1982 Dam Slope Seismicl.gsz
Directory: S:\PROJECTS\2012 PROJECTS\12-3004C Asheville Pond CCB Exploration\1982 Dam Slope Eval\
Project Settings
Length(L) Units: Feet
Time(t) Units: Seconds
Force(F) Units: Pounds
Pressure(p) Units: psf
Strength Units: psf
Unit Weight of Water: 62.4 pcf
View: 2D
Element Thickness: 1
Analysis Settings
SLOPE/W Analysis
Kind: SLOPE/W
Method: Spencer
Settings
Lambda
Lambda 1: -1
Lambda 2: -0.8
Lambda 3: -0.6
Lambda 4: -0.4
Lambda 5: -0.2
Lambda 6: 0
Lambda 7: 0.2
Lambda 8: 0.4
Lambda 9: 0.6
Lambda 10: 0.8
Lambda 11: 1
PWP Conditions Source: Piezometric Line
Apply Phreatic Correction: No
Use Staged Rapid Drawdown: No
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SLOPE/W Analysis
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Slip Surface
Direction of movement: Right to Left
Use Passive Mode: No
Slip Surface Option: Entry and Exit
Critical slip surfaces saved: 1
Optimize Critical Slip Surface Location: No
Tension Crack
Tension Crack Option: (none)
F of S Distribution
F of S Calculation Option: Constant
Advanced
Number of Slices: 30
F of S Tolerance: 0.001
Minimum Slip Surface Depth: 0.1 ft
Optimization Maximum Iterations: 2,000
Optimization Convergence Tolerance: 1e-007
Starting Optimization Points: 8
Ending Optimization Points: 16
Complete Passes per Insertion: 1
Driving Side Maximum Convex Angle: 5 °
Resisting Side Maximum Convex Angle: 1 °
Materials
Compacted Fill
Model: Mohr -Coulomb
Unit Weight: 120 pcf
Cohesion': 370 psf
Phi': 30 °
Phi-B: 0 °
Pore Water Pressure
Piezometric Line: 1
Residuum
Model: Mohr -Coulomb
Unit Weight: 130 pcf
Cohesion': 400 psf
Phi': 32 °
Phi-B: 0 °
Pore Water Pressure
Piezometric Line: 1
Rip Rap and Crushed Stone
Model: Mohr -Coulomb
Unit Weight: 100 pcf
Cohesion': 0 psf
Phi': 40 °
Phi-B: 0 °
Pore Water Pressure
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SLOPE/W Analysis
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Piezometric Line: 1
Slip Surface Entry and Exit
Left Projection: Range
Left -Zone Left Coordinate: (14.91251, 2,070) ft
Left -Zone Right Coordinate: (156, 2,118) ft
Left -Zone Increment: 4
Right Projection: Range
Right -Zone Left Coordinate: (212.19202, 2,146.096) ft
Right -Zone Right Coordinate: (341.39806, 2,134.5) ft
Right -Zone Increment: 4
Radius Increments: 4
Slip Surface Limits
Left Coordinate: (0, 2,070) ft
Right Coordinate: (583, 2,057) ft
Piezometric Lines
Piezometric Line 1
Coordinates
X (ft)
Y (ft)
Coordinate 1
0
2,070
Coordinate 2
60
2,070
Coordinate 3
150
2,080
Coordinate 4
250
2,090
Coordinate 5
400
2,064
Coordinate 6
523
2,062
Coordinate 7
575
2,062
Surcharge Loads
Surcharge Load 1
Surcharge (Unit Weight): 50 pcf
Direction: Vertical
Coordinates
X (ft)
Y (ft)
250
2,170
265
2,170
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.SLOPE/W Analysis
Page 4 of 4
Seismic Coefficients
Horz Seismic Coef.: 0.2
Ignore seismic load in strength: No
Points
X (ft)
Y (ft)
Point 1
0
2,070
Point 2
60
2,070
Point 3
220
2,150
Point 4
250
2,165
Point 5
262
2,165
Point 6
265
2,165
Point 7
523
2,062
Point 8
583
2,057
Point 9
222
2,150
Point 10
250
2,163
Point 11
251
2,164.5
Point 12
253
2,164.5
Point 13
262
2,164.5
Point 14
583
2,030
Point 15
0
2,030
Regions
Material
Points
Area (ft')
Region 1
Compacted Fill
2,3,9,10,11,12,13,5,6,7
23,475
Region 2
Rip Rap and Crushed Stone
3,4,5,13,12,11,10,9
49.75
Region 3
Residuum
1,2,7,8,14,15
20,838
file:///S:/PROJECTS/2012%20PROJECTS/12-3 004C%20Asheville%20Pond%20CCB%... 12/23 /2014