Updated Soil BTV Tech Memo Riverbend

Lip
synTerra
TECHNICAL MEMORANDUM
Date: September 1, 2017 File: 1026.15
To: Sean DeNeale (Duke Energy)
Cc: Kathy Webb (SynTerra)
From: Judd Mahan (SynTerra)
Subject: Updated Background Threshold Values for Soil
Riverbend Steam Station — Mount Holly, NC
An updated background soil dataset for the Riverbend Steam Station (Riverbend) and a revised
version of the Statistical Methods for Developing Reference Background Concentrations for
Groundwater and Soil at Coal Ash Facilities (statistical methods document) (HDR Engineering, Inc.
and SynTerra Corporation, May 2017) were provided to the North Carolina Department of
Environmental Quality (NCDEQ) on May 26, 2017. On July 7, 2017, NCDEQ issued a response
letter (Zimmerman to Draovitch, July 7, 2017) identifying soil and groundwater data for each
coal ash facility appropriate for use in statistical determination of background threshold values
(BTVs) for both media and required that Duke Energy provide these values within 30 days from
receipt of the letter for facilities submitting Comprehensive Site Assessments (CSAs) by October
31, 2017, and 60 days from receipt of the letter for remaining facilities. BTVs (reported as
provisional) along with the revised background soil dataset for Riverbend were submitted to
NCDEQ on August 4, 2017.
The revised background soil dataset used for determination of BTUs and submitted to NCDEQ
on August 4, 2017 met the minimum requirement of 10 valid samples for all constituents except
for antimony, thallium, and selenium because detection limits for these constituents were below
the North Carolina Protection of Groundwater Preliminary Soil Remediaion Goals (POG
PSRGs). To address these requirements, additional soil samples were collected from
background locations on July 27, 2017 (Figure 1). Boring logs associated with additional soil
samples were provided in the August 4, 2017 submittal but are also included herein for ease of
use (Attachment 1). An up-to-date spreadsheet of background soil data that includes analytical
results from the recently collected soil samples is provided as Table 1. The updated
background dataset satisfies the minimum requirement of 10 valid samples. In addition,
detection limits less than the POG PSRGs for antimony, selenium, and thallium were achieved
during laboratory analysis. The updated background dataset was screened for outliers prior to
statistical determinations. Updated BTVs were calculated for all constituents using formal UTL
statistics and are provided in Table 2.
P: \Duke Energy Carolinas\Statistics-LAMA\Background Determinations for NCDEQ July 7 2017\BTV TECH
MEMO \ Riverbend \ Soil \ Riverbend - Updated Soil BTV TM_FINAL.docx

Updated Background Threshold Values for Soil
September 1, 2017
Riverbend Steam Station
LIST OF FIGURES
Figure 1 Background Soil Sample Locations - RBSS
LIST OF TABLES
Table 1 Background Unsaturated Soil Data Summary - RBSS
Table 2 Background Threshold Values for Soil - RBSS
LIST OF ATTACHMENTS
Attachment 1 Soil Boring Logs (Additional Samples)
Page 2 of 2
P:\Duke Energy Carolinas\ Statistics _CAMA\Background Determinations for NCDEQ July 72017\BTV TECH
MEMO \ Riverbend \ Soil \ Riverbend - Updated Soil BTV TM_FINAL.docx

Updated Background Threshold Values for Soil
September 1, 2017
Riverbend Steam Station
FIGURE
P:\Duke Energy Carolinas\ Statistics _CAMA\Background Determinations for NCDEQ July 72017\BTV TECH
MEMO \ Riverbend \ Soil \ Riverbend - Updated Soil BTV TM_FINAL.docx

NOTES:
♦
ALL BOUNDARIES ARE APPROXIMATE.
SITE AERIAL ORTHOPHOTOGRAPHY OBTAINED FROM USDA FSA •
NAIP, DATED 05/27/2016. 1 {
DRAWING HAS BEEN SET WITH A PROJECTION OF NORTH
CAROLINA STATE PLANE COORDINATE SYSTEM FIPS 3200
(NAD83/2011). •
i .
1
I
•
I(-- __
-.� ♦ _ ■_ ■
,, • " WnTerra Hnvw s n A, O m
,', ,�• �� \ \ DRAWN BY: A. ROBINSON DATE: 08/31/2017
• PROJECT MANAGER: J. MAHAN
�� CHECKED BY: B. WYLIE
,�� ��,. ■ \ \ o �n.�., e..,,.,.., o.,,,...,« �noc�nn cie o�ev nnTn�o...,.�.,
—••M••=11�11=11jul1"Ilan
148 RIVER STREET, SUITE 220
GREENVILLE, SOUTH CAROLINA 29601
PHONE [phone]
■
I
1
1
1
1
1
1
♦
ADDITIONAL BACKGROUND SOIL
SAMPLE LOCATION
EXISTING BACKGROUND SOIL SAMPLE
LOCATION -ACCEPTED BY NCDEQ
WASTE BOUNDARY
COMPLIANCE BOUNDARY
DUKE POWER RIVERBEND PLANT
BOUNDARY
FIGURE 1
BACKGROUND SOIL
SAMPLE LOCATIONS
RIVERBEND STEAM STATION
MOUNT HOLLY, NORTH CAROLINA

Updated Background Threshold Values for Soil
September 1, 2017
Riverbend Steam Station
TABLES
P:\Duke Energy Carolinas\ Statistics _CAMA\Background Determinations for NCDEQ July 72017\BTV TECH
MEMO\ Riverbend \Soil \Riverbend - Updated Soil BTV TM_FINAL.docx

TABLE 1
UNSATURATED BACKGROUND SOIL DATA SUMMARY
RIVERBEND STEAM STATION
DUKE ENERGY CAROLINAS, MOUNT HOLLY, NC
Analytical Parameter
yt
p H
Aluminum
Antimony
y
Arsenic
Barium
Beryllium
ry
Boron
Cadmium
Calcium
Chloride
Chromium
Cobalt
Co
Copper
Iron
Lead
Magnesium
Manganese
Mercury
Molybdenum
Nickel
Nitrate
(as N)
Potassium
Selenium
Sodium
Strontium
Sulfate
Thallium
Vanadium
Zinc
PSRG Protection of Groundwater
NE
NE
0.9
5.8
580
63
45
3
NE
NE
360000
0.9
700
150
270
NE
65
1
NE
130
NE
NE
2.1
NE
NE
NE
0.28
6
1200
Reporting Units
S.U.
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
mg/kg
Sample ID
Sample
Collection Date
Analytical Results
BG-ID (5-6)
6/3/2015
4.6 j
12100
---
---
20.4
._
<0.32
E162
9
---
11.6
32200
i-3-7
<162
29.1
0.048
<3.2
1.3 j
---
<325
---
<325
<3.2
�_..
---
89.2
<6.5
BG-1D (14-15)
6/3/2015
5.6 j
11600
---
---
77.3
E297
<0.41
E9.99
F207
E427
5.5
5 j
15.1
26800
4.9 j
2-75@.
226
0.0095 j
<4.1
3.4
---
2580
---
<414
<4.1
_
---
70.2
12.5
BG-1D (24-25)
6/3/2015
5 j
14100
---
---
175
E29.5
0.25 j
E0.98-
E-205
e394
5.4
22.8
25.2
28200
6 j
1140
<0.013
<4.1
6.4
---
6500
---
<410
<4.1
---
75.8
34.7
BG-3D (3-5)
6/13/2015
4.8 j
23100
---
---
28.4
.-
0.33
Q.75
E-157
E313
17.4
---
11.4
526
114
0.027 j+
<3.1
6.7
E31.3-
586
---
<314
1.7 j
_
---
67.5
24.6
BG-3D (18.5-20)
6/13/2015
6 j
26000
---
---
240
E}5-.4
0.66
E9.74
i330AN
14.4
14.6
16.4
23800
4.2 j
943
<0.01
<3.1
8.3
E39.9-
6450
---
<307
10.4
---
62.3
43
BG-3D (23-24)
6/13/2015
5.8 j
26700
---
---
276
E1sr.(�,
0.84
E9.75i
i426
---
6.1
11
10.4
18100
3.7 j
626
<0.01
<3.1
7.6
- ..
6419
---
<311
16.2
---
---
45.4
45.8
GWA-5D (58.5-60)
4/10/2015
5.2 j
3340
---
---
28.7
0.22 j
E9.83
Ei72
.
3.2
13.5
7.1
18600
4.5 j
<172
477
<0.011
<3.4
<1.7
---
<344
---
<344
<3.4
---
33.6
6.8 j
GWA-6D-1 (43.5-45)
3/4/2015
5.4 j
2380
---
3.4
75.5
44-:9
0.29 j
Q..41
34-1
E353
7.3 j+
25.4
23.2
19000
4.6
92.1 j+
1270
<0.01
<0.68
4.2 j+
---
105 j+
---
<68.1
<0.68
---
55.8
3.6 j+
GWA-6D-2 (48.5-50)
3/4/2015
5.5 j
13200
---
4.4
176
9
0.3 j
E9.53
4250
«46 j
1.2 j+
10.5
28.1
18200
2.6 j
523
<0.01
<0.89
2.4 j+
---
---
156 j+
23-:8
GWA-21D (3.5-5)
7/15/2015
5 j
37489
---
37.7
E21.4
0.41 j
E4
37-9
E492
624
---
7.6
64009
29-9
232
153
<4.3 j
3.5
4&2
275 j
---
<427
7.1
E492-
---
---
17.3
GWA-21D (8.5-10)
7/16/2015
5 j
5430 j+
---
3.6 j
2.5 j+
. "
<0.3
E$7-1
---
---
17.7 j+
---
5.2 j+
38300
3.2 j
---
92.7
0.0077 j
<3 j
<1.5 j
---
---
---
<3 j
---
---
---
<5.9 j
GWA-21D (18.5-20)
7/16/2015
5 j
4250
---
---
3.7 j
E1$4
0.44
E9c8$
16.9 j+
5.3 j
7.9 j+
26600
<7.4 j
<184 j
68.4
0.0098 j
<3.7 j
10.2
<368 j
---
<368 j
<3.7 j
<'"'
---
35.5 j+
GWA-21D (48.5-50)
7/18/2015
5.2 j
2070
---
---
113
E15.7j
0.24 j
E.75
---
---
3.2
4.5 j
16
14300
<6.3
---
592
<0.01 j
<3.1 j
2.9
39:2-j
---
---
---
<3.1
---
---
---
20.2
MW-78R (43.5-45)
4/24/2015
5.4 j
5650 j
---
---
31.3
323
<0.32
E0.77
3.6
7.3 j
4.5
12300 j
3.7 j+
620
446 j
<0.01
<3.2 j
2.4
---
216 j+
---
<321
<3.2
,....-..
29.2
6.6
OB-2 (38.5-40.0)
4/14/2015
5.5 j
14400
---
---
157
26.7
1.2
Ei-1
1_5 g
E4B6
2.7
36.1
41000
<9.5
<0.015
<4.7
11.4
---
2440
---
<474
3 j
E488
---
BGSB-04 (4-5)
07/27/2017
4.5
22000
<0.51
13
0.34
<-5.9
<0.025
<290
<12
1.1
13
36000
1-5
220j
57
<0.088
1.4j
6.3
<0.24
310
1.2j
<290
5.5
<12
110
23
BGSB-04 (9-10)
07/27/2017
4.3
22000
<0.58
3.6
14
0.31
2j
<0.029
<230
<12
18
0.95
9.6
16000
8.4
170j
43
<0.083
0.82j
2.9
<0.23
320
0.56j
<230
2.4
<12
0.131
51
15
BGSB-04 (14-15)
07/27/2017
4.7
19000
<0.59
1.5
5.8
0.19
2.3j
<0.03
<280
<12
12
0.93
4
21000
5
100j
27
<0.09
<2.2
<2.2
0.072j
130j
<280
0.6j
<12
0.044j
51
5.9
BGSB-05(4-5)
07/27/2017
6.3
23000
<0.49
3.2
50
0.42
<5.2"
0.016j
530
<12
24
8.6
24
27000
9.6
969
390
<0.1
0.68j
7.3
<0.25
600
0.95j
<520
11
<12
073
88
24
BGSB-05(9-10)
07/27/2017
6.3
17000
<0.47
3.8
35
0.24
2.4j
<0.024
410
1.2j
15
8
13000
9.2
440
110
<0.09
0.68j
3.6
0.075j
480
0.81j
<290
9.7
<12
G4
37
14
BGSB-05(14-15)
07/27/2017
5.8
25000
<0.59
3.5
14
0.26
2.3j
<0.029
77j
<12
18
1.3
7.9
16000
260j
45
<0.086
1j
3
<0.23
360
0.65j
<280
5.3
<12
0.14j
39
13
BGSB-06 (4-5)
07/28/2017
4.6
18000
0.15 j,M
1.5
12
0.37
<1.6
0.015j
240
2.8j
13
2.2
18
18000
4.9
490
23
0.032j
<1.3
3
200
0.41j
<160
4.7
<12
0.058j
51 M
7.8
BGSB-06(9-10)
07/28/2017
4.5
13000
<0.62
0.49j
33
0.46
<2
0.023j
<200
1.9j
12
5.8
16
15000
1.6
320
150
0.05j
0.54j
3.1
0.084j
230
0.41j
<200
0.4j
<13
0.068j
40
5.3
BGSB-06(14-15)
07/28/2017
4.4
17000
<0.56
1.4
240
1.5
ij
0.032
<230
2.5j
7.9
33
20000
2A
320
<0.099
<1.9
7.2
0.085j
290
0.75j
<230
0.44j
<13
0.058j
110
9
BGSB-07 (4-5)
07/27/2017
4.6
20000
0.13 j,M
3.8
15
0.36
2.3 j
<0.03
<240
<12
16
1.4
12
21000 M
-187F
240
43
<0.099 M
1.8 j
1.1 j
0.07 j
310
0.95 j
<240
2.2
<12
0.2-i
86
8.8
BGSB-07 (9-10)
07/27/2017
4.7
8400
<0.52
1.2
7.9
0.19
1.4 j
<0.026
<280
<12
20
0.42 j
7.5
11000
5.5
120 j
14
<0.093
1 j
<2.2
00.24
240 j
0.53 j
<280
1 j
<12
0.089 j
59
3.4
BGSB-07 (14-15)
07/27/2017
4.7
11000
<0.6
0.89
8
0.17
1.5 j
<0.03
<270
<13
25
0.4 j
7
9500
3.7
190 j
<0.098
0.7 j
<2.2
<0.25
240 j
36 j
<1.2
<13
0.061 j
53
3
BGSB-08(4-5)
07/27/2017
4.9
9900
<0.49
0.75
22
0.64
0.026
<240
<11
2.9
10
30000
1.6
160j
260
<0.09
<1.9
2j
<0.23
210j
0.65j
<240
1.4
<11
0.091j
67
18
BGSB-08(9-10)
07/27/2017
4.8
18000
0.27j
0.46j
34
1
2.2j
<250
<12
3.4
31
52
21000
3.6
2201
880
<0.098
<2
2.2
<0.24
91j
0.4j
<250
3.4
<12
71
15
BGSB-08(14-15)
07/27/2017
4.9
17000
<0.56
0.94
28
0.92
2j
0.017j
<240
<12
2.5
30000
7.8
450
1300
<0.089
<1.9
1.7j
<0.25
230j
1.2j
<240
<1.1
<12
0.11j
100
17
BGSB-09 (4-5)
07/27/2017
6.3
21000
<0.54
0.84
82
0.79
1.3j
<0.027
<12
18
23
1.6
9409
310
<0.093
0.44j
0.087j
1300
0.83j
190j
,34
<12
0.048j
53
32
BGSB-09(9-10)
07/27/2017
6.7
59000
<0.56
2
110
0.54
1.8j
<0.028
6j
14
6.6
12
23000
��5.2
2080
120
<0.11
1.1j
6.4
3-4
1200
1.2j
E1500
11
48
0.1j
59
30
BGSB-09(14-15)
07/27/2017
6.37
0.28i
0.53j
190
0.54
1.2j
<0.027
410
4.5j
4.1
19
6.8
13000
300
<0.094
0.81j
5.7
1 0.36 M
2700
1.3j
I 110j
11
<12
0.052j
33
41
Prepared by: JHG Checked by: BDR
Notes•
--- - Not applicable; non -detect concentration greater than PSRG Protection of Groundwater; value omitted
- Indicates data removed/identified as an outlier
< - Less than
j - Estimated concentration above the adjusted method detection limit and below the adjusted reporting limit.
j- - Estimated concentration, biased low.
j+ - Estimated concentration, biased high.
M - Matrix spike / matrix spike duplicate failure.
mg/kg - milligrams per kilogram
NE - Not established
PSRG Protection of Groundwater - NCDEQ IHSB Preliminary Soil Remediation Soil Remediation Goals Table - October 2016
S.U. - Standard Units
P:\Duke Energy Carolinas\Statistics_CAMA\Background Determinations for NCDEQ July 7 2017\BTV TECH MEMO\Riverbend\Soil\Tables\TABLE 1 - Riverbend Updated BG Soil Data for TM Page 1 of 1

TABLE 2
BACKGROUND THRESHOLD VALUES FOR SOIL
RIVERBEND STEAM STATION
DUKE ENERGY CAROLINAS, LLC, MOUNT HOLLY, NC
Parameter
Reporting Unit
PSRG Protection
of Groundwater
BTV
PH*
S.U.
NE
4.3 - 6.7
Aluminum
mg/kg
NE
31,151
Antimony
mg/kg
0.9
0.6
Arsenic
mg/kg
5.8
3.8
Barium
mg/kg
580
190
Beryllium
mg/kg
63
1.66
Boron
mg/kg
45
2.3
Cadmium
mg/kg
3
0.03
Calcium
mg/kg
NE
410
Chloride
mg/kg
NE
12
Chromium
mg/kg
360,000
20
Cobalt
mg/kg
0.9
58.6
Copper
mg/kg
700
33.1
Iron
mg/kg
150
40,150
Lead
mg/kg
270
11.3
Magnesium
mg/kg
NE
760
Manganese
mg/kg
65
1,867
Mercury
mg/kg
1
0.099
Molybdenum
mg/kg
NE
1.83
Nickel
mg/kg
130
10.2
Nitrate (as N)
mg/kg
NE
0.25
Potassium
mg/kg
NE
2,440
Selenium
mg/kg
2.1
1.58
Sodium
mg/kg
NE
427
Strontium
mg/kg
NE
18.3
Sulfate
mg/kg
NE
12
Thallium
mg/kg
0.28
0.166
Vanadium
mg/kg
6
113
Zinc
mg/kg
1200
60.5
Prepared by: JHG Checked by: MCM
Notes•
* - Upper and lower threshold values calculated for parameter
S.U. - Standard Unit
mg/kg - milligrams per kilogram
NE - Not Established
P:\Duke Energy Carol i nas\Statistics_CAMA\Backg round Determinations for NCDEQ July 7 2017\13TV TECH MEMO\Riverbend\Soil\Tables\TABLE 2 -
Riverbend Soil BTVs_Updated Page 1 of 1

Updated Background Threshold Values for Soil
September 1, 2017
Riverbend Steam Station
ATTACHMENT 1
SOIL BORING LOGS (ADDITIONAL SAMPLES
P:\Duke Energy Carolinas\ Statistics_CAMA\Background Determinations for NCDEQ July 72017\BTV TECH
MEMO \ Riverbend \ Soil \ Riverbend - Updated Soil BTV TM_FINAL.docx

PROJECT: DEC Riverbend
WELL / BORING NO: BGSB-4
PROJECT NO: 1026.15
STARTED: 7/27/17 COMPLETED: 7/27/17
DRILLING COMPANY: Geologic Exploration
NORTHING: 592378.47 EASTING: 1414888.646
DRILLING METHOD: GeoProbe
ELEVATION ft M.P. ELEV: ft
BOREHOLE DIAMETER: 3 IN
WATER: ft TOC TOTAL DEPTH: 15.0 ft BGS
NOTES: Coordinates obtained with hand held GPS unit.
LOGGED BY: B. Wylie CHECKED BY: A. Lefitz
U
O
CL
O0
OJ Z
a
w$
Q
DESCRIPTION
Q
CONSTRUCTION
p
D:
0
�V
m0
CL
Hard red sandy clay with sub -rounded gravel, dry,
medium plasticity, non -cohesive.
5
Hard red sandy clay with sub -rounded gravel and light
CL
brown sand grains, dry, medium plasticity,
non -cohesive.
10
Hard red sandy clay with sub -rounded gravel and light
CL
brown sand grains, dry, medium plasticity,
non -cohesive.
CH
Red clay with sand, dry, plastic, cohesive.
15
20
25
30
35
CLIENT: Duke Energy Carolinas, LLC
SynTerra
148 River Street, Suite 220 PROJECT LOCATION:
SynTerra Faxn864 679 371199 PAGE 1 OF 1

PROJECT: DEC Riverbend
WELL / BORING NO: BGSB-rJ
PROJECT NO: 1026.15
STARTED: 7/27/17 COMPLETED: 7/27/17
DRILLING COMPANY: Geologic Exploration
NORTHING: 592761.758 EASTING: 1415348.822
DRILLING METHOD: GeoProbe
ELEVATION ft M.P. ELEV: ft
BOREHOLE DIAMETER: 3 IN
WATER: ft TOC TOTAL DEPTH: 15.0 ft BGS
NOTES: Coordinates obtained with hand held GPS unit.
LOGGED BY: B. Wylie CHECKED BY: A. Lefitz
U
O
CL
O0
OJ Z
a
w$
Q
DESCRIPTION
Q
CONSTRUCTION
p
D:
C7
<
�V
m0
ML
Dark brown silt, dry, non -plastic, non -cohesive.
5
CH
Dark brown clay with some silt and sand, dry, plastic,
cohesive.
SM
dark brown sand with silt, moist, non -cohesive.
10
CL
Brown red clay, dry, plastic, cohesive.
CH
Stiff red clay with sand, moist to dry, medium plasticity.
15
20
25
30
35
CLIENT: Duke Energy Carolinas, LLC
SynTerra
148 River Street, Suite 220 PROJECT LOCATION:
SynTerra Faxn864 679 371199 PAGE 1 OF 1

PROJECT: DEC Riverbend
WELL / BORING NO: BGSB-6
PROJECT NO: 1026.15
STARTED: 7/27/17 COMPLETED: 7/27/17
DRILLING COMPANY: Geologic Exploration
NORTHING: 591563.361 EASTING: 1412422.008
DRILLING METHOD: GeoProbe
ELEVATION ft M.P. ELEV: ft
BOREHOLE DIAMETER: 3 IN
WATER: ft TOC TOTAL DEPTH: 15.0 ft BGS
NOTES: Coordinates obtained with hand held GPS unit.
LOGGED BY: B. Wylie CHECKED BY: A. Lefitz
U
O
CL
O0
OJ Z
a
w$
Q
DESCRIPTION
Q
CONSTRUCTION
p
D
0
�V
m0
ML
Stiff brown silt with clay, dry, non -plastic.
CH
Red clay with silt, dry, plastic, cohesive.
5
ML
Red silt with clay, dry, non -plastic, non -cohesive.
10
ML
Red silt with clay Regolith, dry, non -plastic,
non -cohesive, with white mottles and some structure.
15
20
25
30
35
CLIENT: Duke Energy Carolinas, LLC
SynTerra
148 River Street, Suite 220 PROJECT LOCATION:
SynTerra Faxn864 679 371199 PAGE 1 OF 1

PROJECT: DEC Riverbend
WELL / BORING NO: BGSB-7
PROJECT NO: 1026.15
STARTED: 7/27/17 COMPLETED: 7/27/17
DRILLING COMPANY: Geologic Exploration
NORTHING: 592761.006 EASTING: 1415830.707
DRILLING METHOD: GeoProbe
ELEVATION ft M.P. ELEV: ft
BOREHOLE DIAMETER: 3 IN
WATER: ft TOC TOTAL DEPTH: 15.0 ft BGS
NOTES: Coordinates obtained with hand held GPS unit.
LOGGED BY: B. Wylie CHECKED BY: A. Lefitz
U
0-0
CL
O0
OJ Z
a
w$
DESCRIPTION
Q
CONSTRUCTION
p
D
0
�V
m0
SM
Brown sand with silt, organics, and some gravel, dry.
5
MH
Red to light brown silty saprolite, regolith, relict
structures and mottles.
10
MH
Brown silt with minor fine sand and white mottles, not
much structure.
15
20
25
30
35
CLIENT: Duke Energy Carolinas, LLC
SynTerra
148 River Street, Suite 220 PROJECT LOCATION:
SynTerra Faxn864 679 371199 PAGE 1 OF 1

PROJECT: DEC Riverbend
WELL / BORING NO: BGSB-8
PROJECT NO: 1026.15
STARTED: 7/27/17 COMPLETED: 7/27/17
DRILLING COMPANY: Geologic Exploration
NORTHING: 593115.196 EASTING: 1416274.469
DRILLING METHOD: GeoProbe
ELEVATION ft M.P. ELEV: ft
BOREHOLE DIAMETER: 3 IN
WATER: ft TOC TOTAL DEPTH: 15.0 ft BGS
NOTES: Coordinates obtained with hand held GPS unit.
LOGGED BY: B. Wylie CHECKED BY: A. Lefitz
w$
p
U
Q O
D:
C�
DESCRIPTION
CL
O0
�V
OJ Z
m0
a Q
CONSTRUCTION
MH
Dark red silt with sand and some gravel, dry,
fine-grained.
5
MH
Dark red brown silt with clay regotlith and fine sandy
zones, dry. Weathered, clay mottles.
10
15
20
25
30
35
CLIENT: Duke Energy Carolinas, LLC
SynTerra
148 River Street, Suite 220 PROJECT LOCATION:
SynTerra Faxn864 679 371199 PAGE 1 OF 1

PROJECT: DEC Riverbend
WELL / BORING NO: BGSB-9
PROJECT NO: 1026.15
STARTED: 7/27/17 COMPLETED: 7/27/17
DRILLING COMPANY: Geologic Exploration
NORTHING: 591043.984 EASTING: 1410107.754
DRILLING METHOD: GeoProbe
ELEVATION ft M.P. ELEV: ft
BOREHOLE DIAMETER: 3 IN
WATER: ft TOC TOTAL DEPTH: 15.0 ft BGS
NOTES: Coordinates obtained with hand held GPS unit.
LOGGED BY: B. Wylie CHECKED BY: A. Lefitz
w$
p
U
Q O
D
0
DESCRIPTION
CL
O0
�V
OJ Z
m0
a Q
CONSTRUCTION
SM
Medium gray to brown silty sand, moist to dry,
non -plastic, non -cohesive.
5
10
MH
Red silty clay, moist to wet, medium plasticity,
cohesive.
SM
Gray fine to medium silty sand, dry, non -plastic.
SM
Saprolite, silty sand with minor structure, moist to dry,
non -plastic, semi -cohesive.
15
20
25
30
35
CLIENT: Duke Energy Carolinas, LLC
SynTerra
148 River Street, Suite 220 PROJECT LOCATION:
SynTerra Faxn864 679 371199 PAGE 1 OF 1