3612_Allen_ModifiedClosurePlan_Rev2_Figures and Tables_FID1897207_20230731

FIGURES

FIGURE 1-1
mv• A
iT # ALLEN STEAM STATION
■ 1
bm
ar
I
* •
' �` `� ` r� • PLANT ALLEN RD f r • COAL YARD
41
hp
��r' I r L i •yiL S I Iz; +Ia===aa 1 JED _
HOLDING
ok
BASINS
Ell -dm
ro
ASH M �I '� ' _ ; •
�- STORAGE 1 ■ 1 I l
RETIRED ASH BASIN
RETIRED ASH BASIN DIKE
■• _ _ _ +i� FR �� '',a♦ �; ; ; ,I r� ' (GASTO-016)
f
f
91
p ASH
I I I + I
j �..►;� FILL i
i I ASH + _ RETIRED ASH BASIN i '
,
��I 1
FILL 1 I ♦oft-_w-ft --- ft_% I F�.__
LL LL LL LL LL
' � • �� ; ; ; I1 I r I
' : y 1 i ■I�I 1 iI
mmY I I I
60
- ASH
* RETIRED ASH BASIN STORAGE RETIRED ASH BASIN LANDFILL r
_ _ T go � I �I!+ � _j PERMIT NO. 36-12 �
y��+ 7 I 'tr I I� I� IIl I I
1A 1 1 1 1 I I+r rl
-, � I� I 1 III I r1 I1
a I j I J 1
_ I • 1 1
1 J�1 rF ■ ; a�r� ��,, ; ; mill. I
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I _ ��.♦ �11 _ Ij� .._._._.._�._....
lillip
4
or
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Rl
_ IFdkF H BASIN -
ti II --
1! ACTIVE AS
NORTH DIKE­
440 i
r + %ok.
Ill-
' �
_ PRIMARY POND 3 r
APPROX.
* PRIMARY PRIMARY POND 2 �L PRE -DECANTING
' IFF POND 1 APPROX. WSE 640.0'
1 } f :1111 - - PRE -DECANTING _ '*
• �� _ �+■ WSE 640.0'
ai
RE ow qp
-in -8
41Adill dp
At' �i i ■ . T
r i
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- f ir
ha Ri- Pi
-
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i
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r 1
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ui
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P POLISHING POND t :.
- PRE -DECANTING
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ACTIVE ASH BASIN
1 f
1
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-
tl � ■
r _IF
r dP 1
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• i 1 ! - ' 4
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R ti
F - _ - I
Ilk
_ + r L .- 1
2 3 TENTHS 10 20 30 4 1 1
LAKE WYLIE/
CATAWBA RIVER
NORMAL W.S.E.
565.7 FT.
YLIE/
CATAWBA RIVEI
NORMAL W.S.E
565.7 FT.
N
0 300 600 900
GRAPHIC SCALE (IN FEET)
0,
RAB
I
CATAWBA RIVER/
°`���" �L�� •� �_ :\� a LAKE WYLIE
AAB
"
IM
0 2000 4000 6000 N
GRAPHIC SCALE (IN FEET)
LEGEND
DUKE ENERGY PROPERTY BOUNDARY
APPROXIMATE LIMITS OF IMPOUNDED ASH
APPROXIMATE ASH BASIN WASTE BOUNDARY
•________________• ASH STORAGE BOUNDARY
W.S.E. WATER SURFACE ELEVATION
TITLE
FIGURE 1-1 VICINITY MAP AND SITE PLAN
ALLEN STEAM STATION
CCR SURFACE IMPOUNDMENT CLOSURE PLAN DRAWINGS - CIP
GASTON COUNTY, NORTH CAROLINA
N.C. ENGINEERING LICENSE NO. FOR F-0342 ISSUED FOR APPROVAL
S SCALE: DES: ANR
DUKE DWG TYPE : • DWG DFTR : AMC
JOB NO: 60603204 CHKD: JDM
ENERGY® DATE: 12-12-19 ENGR: JDM
FILENAME: FIGURE 1-1 SITE LAYOUT PLAN . DWG APPD: JDM
DWG SIZE DRAWING NO. REVISION
ANSI FIGURE 1 -1
22.0"x34.0" A
9 10
Fl
C
m
i

FIGURE 3-1 1 mv. A
�G-2S
3G-2D
G-2 /
3G-2BR BG-2BRA-2
ro-�j
GWA-16
GWA-16D
GWA-16S
INCHES
G
0
GWA-8SA
GWA-7D ALLEN STEAM STATION
\\\ / -, ,`I �� \ E \ 0 GWA-7S
I / ` \ �11 r\ , \`\ _ _,__� . , GW��Ay-8S ��
J
I \ _ r \., ._ - I � d� � \ GWA-7 J i I iii `-- _ _ BGSB-GW-8 NA-8 w ' 3Q \ \ \ 1 I\
GWA_-17S_ =_ �r / 0 3\��E
3 / it
—\ \ 30 0 / 0 1 ��� j� �� / �_ \ • ` \ \.
t 1�` 1 / \\
-- GWA-17D � rvr ..� ` - � � /�, `_, ,\
— 30 — / / iii' _ - \ r ` ` 4 \ / I \ r \\1
CCR-3DA ,%%' ;CCR-3S. `�GWA-6S
AB-1 --~__ CCR-1DA\ WEIGH STATION i �li'�-=\ r s//hrJ 111 �����\\ \\ C?
_�
nY - /
--- -- - -- RD 3fl _ _ l GWA-6 r rr-/,Y�/yr Irlr\_ I �I,\�� ` r�
/ / \ /"` _ -- - PLANT ALLEN - CCR-2D; _ _ \ I i `�� GWA-66R G' ,\� , ' / •,/ , /�li It(" \\� \ \
' / GWA-18D 1 ,� \ _ , / COAL YARD "111 II N\\r 0 �C 1
1 1 c \ _ . �_ \ GWA-6DA.
r � I \ I , i - N I i♦l%i-:� ,�, ; \✓,� � \ may,. , l , / rllr ,, I
GWA-18,3 \ \ , �' ♦ �� �.\ I \\ - 1 I/Iti
1 I J \ e5 CCR-3D l I
® / / ` I \ - / CCR-1SD \ / �- -- ii I I1 �\ \ �\ \ .-1/ /I it I LINED / I
I \ . / -- . I CCR_ 1 / l rbl l II
�'' /' ` / I I ` ` I '� i i�--- .,• /I"I;fii.� / \ \ CR-4D' GWA-6D ✓" r It/ 1 I a
l � � z, nl„ � r l I v , I HOLDING
GWA-18 /- I • CCR-2S _ 1 \ 4, }� r \ h „✓ Ji I Ili„ \\\ of
/ !, i .' ; f .. I I ( ,�i/, ■ �� i 1� /'%�. ,i \ ) \\ i \\\ ` I Ili/ BASIN �\\
ASH STORAGE ,
--� / ' CCR
EX. SLUICE //- \\ \
/ a\
ow o , — ' PIPES CCR-4DA \` CCR-5D/ r '\``_\r i II CCR-8' \\
I r, AB-39S I 41! I� t''II'
I t� I lol to CCR-5S \ / p �1 r-- ►, _ _ - h^ I
RETIRED ASH IAB-38BR
�Io / 1 r/ I Icfll ico \C\ ``CCR-7D <- - ��^ '=
BASIN I� r I III I IIII \� �`\ -____' . r CPT-URS-5-S
(II / ,fir i f- ` AB-38D / 1 , T I I II!� li II OW_3 �`�\ /~„I'\� — _---- - �o/
� � �I I B- - � c CCR-9D
1AB-38S' / , AB-39D 1 I AB-39 IIIII I \\`� CCR-Fn� CCR-7 ` , I .-
I AB-38 0 "I ' \ 1� �I li II I B 4 = _3 RETIRED ASH BASIN DIKE =_
\\\
Ir ',( I ,!I11 II 1 I� ��II I� Illii TL 1A482 — �
I \ 11 r f- , II 111 foil I / (GASTO-016 DW-5�\\\\�\\cl CCR-9S
TL 1A606 \ - 111 I I I / (100kV) _ ) \
rl I CCR-BG-1S\ 1 100kV ` I I ` f 1 II 'I�• II I III i " `'�
CCR-BG e 1D� I c �\ \ \ 1\ 1 .' I f il� �Illil it n II I CCR-6S � AL,�,S,SS � �?\\ ,i GWA-5D
-- B-15'%I I`I\ GWA-5S
_ \ ^ uI1II11
I fl //—� I■ 111 �I I I ��III I ,I , /� ; 1 1� �\�� �- f IIII III GWA-5
TL 5N5 : I �I IIII I I II 1 /^� \\ \ .. III I
11 7 ASH FILL 2 I I IIII I / \, AB-32 II I
BG-1 D' ► 11 OW-7 — P.I: �, - ► / nll II
\ (500kV) I _/ /' IIIIII I I III I /~ \ \\ // III I I
/ I \BG-1 S II // II 11II B-6';� _ ` \�: �_� AB �32S IIIIII GWA-5BR
I I III I !�� � \ . �
♦ /�\\/ I` \\ ���� _�i ' I jI // 4110 lil�i I IIlil '� ��- --- /, / 1 \\ I
%1 � I r �_________ = RETIRED ASH BASIN AB-32D p,l
II �ti/ __/ ./ \6 `� / � TL 2A10 ` �( \11 w ASH FILL 1 I� --- ��— �� Ilion B-11
0� ._ \ � co, � `-- ---- %''�= `:\ OW-10 II toll GWA-SBRA
GWA-19D �/ ,---.\� — ? --\ ; i Ir (230kV) •' ♦til s_ 1\\'\� I I''I I Ilii 1 �v r--% . \ 1 `: — III'll I I I
i' / / \ / / / ���\ I I �' I �yaaaaaaaa \ -- Saar- -- \\I �\ _ I I
/�,\ \_/. I l/fp`- . I i /,--- \ \II I I I I II III AB-34D :�'--� ----_9 �.. f l 1 \ / , IIII III I CCR-11 S
I -- �' — I ' �l 1 I I IIII �`� ��� ,�'1'Mlaa-- �sa� PZ-26-3 IIIIIIII
- � ----- T----, ul I I CCR-11 D
ASH FILL I I I i Jr -----� L 1 , — _ I
I lil 1 I I I I OW�8— - ` ---- ------ - I I I I
' ------------'- -'� - '/ v ``� I SLOPE I I , AB-34S III I III -- --- -=.-1 \ — _ _------_='-------- - 1 r II111 II
I I II III II 11 I I I--_ ----__---- _ �\��______- — — — — — — — = - -� I IIII III CCR-11 DA
/ 1 1 0 0 i DRAIN I IIII IIIIII I / I I ----------- I I ft I I IIIIII =--------------- �__----__--------------- ---- III III I I
1l �I Ir� 1I lI,II(III II (TYIlII lI iIIlI I��Ia lIIlII IIllI — I 1 �`I��IIII lIjlIIIIIIII IIIIII1rj�I IIIIl ITIIl i1 IjIlI r IlI Il!I —
-- 13iF AB-37D.' 11 )
woo'1I j
`' _ \ 1IIIIIIIIIIIII IIII I 1 AB-37S RETIRED ASH RETIRED ASH BASIN LANDFILL
PERMIT NO. 36-12 1III III PInIIIIIIIIIZ
IIB IuII �I-1I'
I�I
1I
2
S-1B-
I
-%
BASIN31
e AB-37 *I ASH STORAGL1y vl I'll rl - _OW
-16
r,l
IIGWA-15S-AB-36D LANDFILL SLOPE DRAINS IAB-31D GWA-4
I. O O 11 I I AB3515SII1-II I SR
I I III, I II II I (TYP., LOCATION TWIN EX.
AB-36,i APPROXIMATE) PIPES TWIN EX. PIPES
-36S woLO AB 1I`-GWA-15� o O101I 101-714 1101, .1 I II B-21
M
100-YEAR
FLOOD
ELEVATION:
571.3 FT.
-to WA - IOU \ _\ ` 1� - I I I I CO III LtO - �,1 ma 1 TWIN EX. 36 RCP PIPES \\II PZ-2B-1 �l,l r 1111.11 EMERGENCY
\ \ IIII \\ ' I I I ® — — — —= 675 --\I l\__ -- n I I �I i
\ I \ I III II //// II I II it _ _ _ — _______--___ _-` _r0 �i I
11 , IIIIII I I I �___.__ _� Fj CV'IO� SPILLWAY
J / \\ / III I I cc c _ I ` -` �\ i 1 �`�� J t. I � I III II , / v I I 1 I L_ — - - ----
AB
' � / \ . +III // // , I I I____
-AB-14BR' `\� \ I IIII / _ ___ TWIN EX. PIPES . -= AB-29=
o \ \ \�� r i \I� :! i _ OW-18 __a -_ _ AB-__29S_L_ _-' Ilnlli� AB-9S
�' \--- AB-14D _ _ - "1 \�� �� �i; il��%��,ww �� _-_ - -- 'i�i PERMITTED SPILLWAY
AB-29D
I'- GWA-19 \ I Tip \ `GWA-14S / _ I \` sw� '� I .� s B-30D. --- CONTROL PANELS I \ i
— GWA-1_ % GWA-14D - _ ; �� {I \ ~ / "' 1 AB-30 AB-30S (TYP., LOCATIONS ;-26- — - , / ; AB-9
APPROXIMATE) rOW- I,+
5 B-24_ __— - j ,co`�'ItCp r,
-\\ 1� \ SSpn, �h�,------ 0550 �!i I�__�\ \I\ 0`L /�l`� _ B=22 r� 27��"SOW-13 i III /
CN,OO / co. \\ - r .A 3 \ I \� �� — �• .�. ACTIVE ASH BASIN •_•�` B 29�;II11 ll� / B-8
GWA-14 _--- I ► 1 % �/ =_=OW-181 -- — — NORTH DIKE �- 15 % AB-27D 111 ,
-',/ B-23 v I r_7 II i i i I I I
\ \ i L�i' / ~� I I NPDES
i \ \ �-'� I OW-22 ' OW- i i AB28 B-28 i , , AB- 7S I- Milli fill
AB-28D - �./
n , ` I / —Al I ' 1111 III OUTFACE
.mein nn.. /B-2 / 1 �' OW-2 I �-AB-28S_ /, �1-AB 127 I Vl Ilill IIII SWO15
GWA-20 I\\ _ i GWA-22S ' c --- /� �` .rJ ,ti ✓. 1 +IICCR-14S l
\ /. - — — — — _ \\ r• B-30 / / ,/ �, 1 1 1 1 IIII I I
OW-21 I p
-2D- OW-1 l I II . �C7 ��®
LAKE WYLIE/
CATAWBA RIVER
NORMAL W.S.E. 565.7 FT.
`--- r PN-1 D i I EX. SLUICE \ g® ��� III i 1 IIIII 11 1 COAL YARD SUMP
\ I \ o Ii I—CCR-14DIiI DISCHARGE
GWA-21BR PIPES B-31 PRIMARY POND 3
(ABANDONED)
—
GWA-21
APPROX. r \
\ \ I I
PRIMARY POND 2 / / PRE -DECANTING 1 1 II I IIII! I
/ PRIMARY I I I I Ito
GWA-1 1S I��3 I �, APPROX. t r q WSE 640�0' i i III I IN tlol
4 f-fir, POND 1 I Ill 11:11! .-
1 650 �v PRE -DECANTING AB-25 _�_ __AB-26
GWA-21D / ` c3 'AB-24S 1 - - _ , II i III I�AB-26D GWA-3BRA
l a` -_-t� __• o r // -WSE 640.0'-- ,
\ , - / / AB-13S " � r AB-25SL Ip I I IIII GWA-3S
\ GWA-21 DA ( - -- \ B-24 /�'~' i / I I I r
.r� i I I 1 tlil GWA-313R
AB-26S III II I
AB-25BRU _ I IIIIII
CPT-URS-11-S , r �, AB-24D AB-_25BR-_\ I-�/� i ill II!II!! - GWA-3
1 l IIII OW-2 GWA-3D
/;P
!�i• /. //�%/,� \1 `
�%.
~I
OW-
6Ol'/j/ W
I _�' �• LAKE WYL4RRIE/AB-�Ail \// CATAWBA RIVER
r•///NORMAL W.S.E.AB-4D ��•
oU1 P3 z 565.7 FT.CHEMICAL j
S� �mAB-23,BUILDING ` >Lu
II it AB-4S__�'�- r/•�0;`V
F_' o
_- ------CCR-16DGW--3S' =_ _ n O
I rn\�AB-23BRU=/ Q
o 11
'cn o s\ >
I I-w < CCR-16S
AB-23\
i
�z`'=--✓+�s���III I Ilill Ilil � \\\ CCR-17S
�i —� -- �— '/ \�\ / / \\___\_/, i''�'' ,�� % l I r 1 , Illll+II \��. \
/cr r� / , , _ �l I POLISHING POND I !I I IIIII III CCR,-1 \7D
' I I `•� '/ 1 l /� I '/i/ �•r l l \ APPROX.\\. \
i /IIIr /GWA-9D, , 1 \ ,,, ► / I /' / j \ L
/ GWA-24i l i t r .►Ire % 1 _ _-- -''/�, ': / /L, / �/ ,/ • 1 \ PRE -DECANTING N I� c,l Ili II
r GWA-9BR I I-� // _r ,/ y . \� c0 I m
--GWA-24D, / GWA-9„� r/ m - ,� „? `% / I / ,� ,� \" ,, \ I III II II I AB-10
� / \ I' / r •\ WSE 635.0 t{I�Ui,I llt III �_.� \
r AB-20S` r \ / 1 \ r1 • ' \ lJ ~ 1 �1 t I IIII lllllll
GWA 24S/ / / / AB-20D o o ; 1 / / I/ I� • • ��. \\ \ i� AB-22S \\ /JI I Iilli i!
AB-20 rn I� + l i \\I'• ' ACTIVE ASH BASIN \ \\ / i> - , I I �_ I AB-10S
GWA-24BR / o GWA � 9S f o AB-21 BRL ' // i / AB-21 S'� `\ J/�\ AB / 22 5 r \\ t I ABI 22BR
o; III ; ,,, o > r \ �►• -- �/OW_81 II i IIIII itl ip� g
�A<0 cat?/ \ co co /f`�i '"'` r7u� , '"'` ''` �h / ,� AB-21SL '"'` ''I'`\\ ,/ 'OW-121
o o �, Il B-21 �,�� `'� i`--� /' P-7 l ll� I lii I II�IIiI!I i
/ / / m ~ � `I � \ /— OW-10 `l ll III OW-11
' I
AB-21 BR J IIIII II n �►
r/ o , /, AB-21 D \ . 1 I�I III I AB-6A
GWA-25. / `--/ 1\ I , \` " \ AB-� 6 l ll I IIIIII V I _1
`'1� I CCR-18D
JURISDICTIONAL STREAM
100-YEAR
FLOOD
ELEVATION:
571.3 FT.
i J w i, / CHEMICAL 1\ .� \ =-"�\ 1 �i I� IIIII dill PERMITTED SPILLWAY
00
11 k- w - ` — ``` `_! CCR-1 8S
BUILDING rr /
xllc • yl�c xllc xllc xllc — — =!i- / j -�
• ,v \\ - EXISTING'/�--//i
cn h \ AB-12S _-- -.\�-' _ — �\ `� WTS PAD
_��j// ��\ \`�` \`\ ` ylic �lic \ ' CCR-21 S I
A13-12,
'AB-12D,/ / _ \ \ \� _ -- - - ---' // r= \ ` \\ \ \ 1 CCR-21 D/'CCR/ 20D CCR-20S
_ \
\ � \ \ \\ \
1 /- 'CCR-22SJ, / l I l
\` \ I ` /% / I / IF
� l GWA-2S/
GWA-26 - - 1 r / \ \ I , �i / / / _ �p
/ / � / CCR-22DA, / / co /
c�s� ~---- ��'' �61 GWA-26S rr `r cfl ; 1 \\ r_`\\ \\\\�\ I \ / ��_--- ,',/ / / I \ , / /' WA-2D,/
\\ \ GWA-26D,?
-\ \
\\\ iG/W/
A-2,/
' 1 / =i BGSB-GWA-26, �\k CC-23S\GWA-I 1D
_ _ 10
i
THS10
t
NPDES
OUTFALL
002
JURISDICTIONAL STREAM
LEGEND
—
— — - 625 - — — —
EXISTING MAJOR CONTOUR (25 FOOT)
EXISTING MINOR CONTOUR (5 FOOT)
DUKE ENERGY PROPERTY BOUNDARY
APPROXIMATE LIMITS OF IMPOUNDED ASH
LIMITS OF EXISTING RAB LANDFILL LINER
LL
------------------
ASH STORAGE BOUNDARY
APPROXIMATE ASH BASIN WASTE BOUNDARY
LIMITS OF WATER
100-YR
100 YR FLOOD LINE
HDR SOIL BORING/GROUNDWATER
AB-X/GWA-X/BG-X
MONITORING WELL LOCATION (2015)
S&ME SOIL BORING/MONITORING WELL
B-X
LOCATION (2010)
S&ME SOIL BORING/MONITORING WELL
TT
B-x/OW-x
LOCATION (2007)
T
AB-x
S&ME EXISTING ASH BASIN VOLUNTARY
GROUNDWATER MONITORING WELL LOCATION (2004)
MACTEC EXISTING ASH BASIN COMPLIANCE
AB-X
GROUNDWATER MONITORING WELL LOCATION (2010)
4
Ow-x
DUKE EXISTING OBSERVATION WELL (1983)
x
P_x
DUKE EXISTING PIEZOMETERS WELL (1983)
CCR-x
CCR MONITORING WELL
HATCH LEGEND
WETLAND (SEE NOTE 5)
POTENTIAL HABITAT - SCHWEINITZ'S
SUNFLOWER (SEE NOTE 4)
NOTES
71-1
1. LIMITS OF IMPOUNDED ASH ARE APPROXIMATE.
2. VOLUME OF FREE STANDING WATER WITHIN THE AAB SHOWN IN THE DRAWING IS
C
APPROXIMATELY 92 MILLION GALLONS BASED ON FEBRUARY 2015 SURVEY BY WSP.
m
3. REFER TO DRAWING SHEET ALN_C901.021.002 FOR REFERENCES.
W
4. POTENTIAL HABITAT FOR SCHWEINITZ'S SUNFLOWER WAS IDENTIFIED BY AMEC'S JUNE
1
24, 2015 NATURAL RESOURCES TECHNICAL REPORT. PRIOR TO LAND DISTURBANCE,
-.JL
THE U.S. FISH AND WILDLIFE SERVICE MAY REQUIRE A BIOLOGICAL SURVEY OF THESE
AREAS.
5. POTENTIAL JURISDICTIONAL WATERS (STREAMS/WETLANDS) WERE IDENTIFIED BY
AMEC'S JUNE 24, 2015 NATURAL RESOURCES TECHNICAL REPORT AND SURVEYED BY
MCKIM & CREED IN FEBRUARY 2016. CONFIRMATION IS PENDING U.S. ARMY CORPS OF
0
ENGINEERS REVIEW.
0 300 600 900
NOT FOR CONSTRUCTION
GRAPHIC SCALE (IN FEET)
TITLE
P"=com
N.C. ENGINEERING LICENSE NO.
F-0342
EXISTING CONDITIONS PLAN
ALLEN STEAM STATION
CCR SURFACE IMPOUNDMENT CLOSURE PLAN DRAWINGS - CIP
GASTON COUNTY, NORTH CAROLINA
FOR ISSUED FOR APPROVAL
SCALE: AS SHOWN DES: ANR
DUKEDWG TYPE :. DWG DFTR : AMC
JOB
�. ENEENERGY®[DATE. 12-12-119 ENGR: JDM
FILENAME: FIGURE 3-1 EX TOPO AND BATHYMETRY.D PPD: JDM
DWG SIZE DRAWING NO. REVISION
ANSI FIGURE 3 -1
22.0"x34.0" Q
10

TABLES

AECOM Table 2-1: NC CAMA Closure Plan Requirements September 20, 2019
Summary and Cross Reference Table
Duke Energy, Allen Steam Station
No.
Description
Corresponding
Closure Plan Section
Part II. Provisions for Comprehensive Management of Coal Combustion Residuals
§ 130A-309.214(a)(4) Closure Plans for all impoundments shall include all of the following:
a. Facility and coal combustion residuals surface impoundment description. — A description of the operation of the site that shall include, at a minimum, all of the following:
1
Site history and history of site operations, including details on the manner in which coal combustion residuals have been stored and disposed of historically.
3.1.1
2
Estimated volume of material contained in the impoundment.
3.1.2
3
Analysis of the structural integrity of dikes or dams associated with impoundment.
3.1.3
4
All sources of discharge into the impoundment, including volume and characteristics of each discharge.
3.1.4
5
Whether the impoundment is lined, and, if so, the composition thereof.
7.1
6
JA summary of all information available concerning the impoundment as a result of inspections and monitoring conducted pursuant to this Part and otherwise available.
3.1.6
b. Site maps, which, at a minimum, illustrate all of the following:
1
All structures associated with the operation of any coal combustion residuals surface impoundment located on the site. For purposes of this sub -subdivision, the term "site" means the land or waters within the property boundary of the
applicable electric generating station.
3.2.1
2
All current and former coal combustion residuals disposal and storage areas on the site, including details concerning coal combustion residuals produced historically by the electric generating station and disposed of through transfer to
structural fills.
3.3
3
The property boundary for the applicable site, including established compliance boundaries within the site.
3.3
4
All potential receptors within 2,640 feet from established compliance boundaries.
3.2.2
5
Topographic contour intervals of the site shall be selected to enable an accurate representation of site features and terrain and in most cases should be less than 20-foot intervals.
3.3
6
Locations of all sanitary landfills permitted pursuant to this Article on the site that are actively receiving waste or are closed, as well as the established compliance boundaries and components of associated groundwater and surface
water monitoring systems.
3.2.3
7
IAII existing and proposed groundwater monitoring wells associated with any coal combustion residuals surface impoundment on the site.
3.3
8
JAII existing and proposed surface water sample collection locations associated with any coal combustion residuals surface impoundment on the site.
3.3
c. The results of a hydrogeologic, geologic, and geotechnical investigation of the site, including, at a minimum, all of the following:
1
A description of the hydrogeology and geology of the site.
4.1
2
A description of the stratigraphy of the geologic units underlying each coal combustion residuals surface impoundment located on the site.
4.2
3
The saturated hydraulic conductivity for (i) the coal combustion residuals within any coal combustion residuals surface impoundment located on the site and (ii) the saturated hydraulic conductivity of any existing liner installed at an
impoundment, if any.
4.3
4
The geotechnical properties for (i) the coal combustion residuals within any coal combustion residuals surface impoundment located on the site, (ii) the geotechnical properties of any existing liner installed at an impoundment, if any,
and (iii) the uppermost identified stratigraphic unit underlying the impoundment, including the soil classification based upon the Unified Soil Classification System, in -place moisture content, particle size distribution, Atterberg limits,
specific gravity, effective friction angle, maximum dry density, optimum moisture content, and permeability.
4.4
5
A chemical analysis of the coal combustion residuals surface impoundment, including water, coal combustion residuals, and coal combustion residuals -affected soil.
4.5
6
Identification of all substances with concentrations determined to be in excess of the groundwater quality standards for the substance established by Subchapter L of Chapter 2 of Title 15A of the North Carolina Administrative Code,
including all laboratory results for these analyses.
4.6
7
Summary tables of historical records of groundwater sampling results.
4.6
8
A map that illustrates the potentiometric contours and flow directions for all identified aquifers underlying impoundments (shallow, intermediate, and deep) and the horizontal extent of areas where groundwater quality standards
established by Subchapter L of Chapter 2 of Title 15A of the North Carolina Administrative Code for a substance are exceeded.
4.7
9
Cross -sections that illustrate the following: the vertical and horizontal extent of the coal combustion residuals within an impoundment; stratigraphy of the geologic units underlying an impoundment; and the vertical extent of areas
where groundwater quality standards established by Subchapter L of Chapter 2 of Title 15A of the North Carolina Administrative Code for a substance are exceeded.
4.8
Page 1

AECOM Table 2-1: NC CAMA Closure Plan Requirements September 20, 2019
Summary and Cross Reference Table
Duke Energy, Allen Steam Station
Corresponding
No.
Description
Closure Plan Section
d.
The results of groundwater modeling of the site that shall include, at a minimum, all of the following:
An account of the design of the proposed Closure Plan that is based on the site hydrogeologic conceptual model developed and includes (i) predictions on post -closure groundwater elevations and groundwater flow directions and
velocities, including the effects on and from the potential receptors and
1
(ii) predictions at the compliance boundary for substances with concentrations determined to be in excess of the groundwater quality standards for the substance established by Subchapter L of Chapter 2 of Title 15A of the North
5.1
Carolina Administrative Code.
Predictions that include the effects on the groundwater chemistry and should describe migration, concentration, mobilization, and fate for substances with concentrations determined to be in excess of the groundwater quality standards
2
for the substance established by Subchapter L of Chapter 2 of Title 15A of the North Carolina Administrative Code pre- and post -closure, including the effects on and from potential receptors.
5.2
A description of the groundwater trend analysis methods used to demonstrate compliance with groundwater quality standards for the substance established by Subchapter L of Chapter 2 of Title 15A of the North Carolina Administrative
3
Code and requirements for corrective action of groundwater contamination established by Subchapter L of Chapter 2 of Title 15A of the North Carolina Administrative Code.
5.3
A description of any plans for beneficial use of the coal combustion residuals in compliance with the requirements of Section .1700 of Subchapter B of Chapter 13 of Title 15A of the North Carolina Administrative Code
e
(Requirements for Beneficial Use of Coal Combustion By -Products) and Section .1205 of Subchapter T of Chapter 2 of Title 15A of the North Carolina Administrative Code (Coal Combustion Products Management).
6.1
All engineering drawings, schematics, and specifications for the proposed Closure Plan. If required by Chapter 89C of the General Statutes, engineering design documents should be prepared, signed, and sealed by a professional
f
7 1 7 2
engineer.
A description of the construction quality assurance and quality control program to be implemented in conjunction with the Closure Plan, including the responsibilities and authorities for monitoring and testing activities, sampling
g
strategies, and reporting requirements.
7.3
h.
A description of the provisions for disposal of wastewater and management of stormwater and the plan for obtaining all required permits.
8
A description of the provisions for the final disposition of the coal combustion residuals. If the coal combustion residuals are to be removed, the owner must identify (i) the location and permit number for the coal combustion
residuals landfills, industrial landfills, or municipal solid waste landfills in which the coal combustion residuals will be disposed and (ii) in the case where the coal combustion residuals are planned for beneficial use, the location and
manner in which the residuals will be temporarily stored. If the coal combustion residuals are to be left in the impoundment, the owner
L
must (i) in the case of closure pursuant to sub -subdivision (a)(1)a. of this section, provide a description of how the ash will be stabilized prior to completion of closure in accordance with closure and post -closure requirements
9
established by Section .1627 of Subchapter B of Chapter 13 of Title 15A of the North Carolina Administrative Code and (ii) in the case of closure pursuant to sub -subdivision (a)(1)b. of this section, provide a description of how the
ash will be stabilized pre- and post -closure. If the coal combustion residuals are to be left in the impoundment, the owner must provide an estimate of the volume of coal combustion residuals remaining.
j.
A list of all permits that will need to be acquired or modified to complete closure activities.
10
A description of the plan for post -closure monitoring and care for an impoundment for a minimum of 30 years. The length of the post -closure care period may be (i) proposed to be decreased or the frequency and parameter list
modified if the owner demonstrates that the reduced period or modifications are sufficient to protect public health, safety, and welfare; the environment; and natural resources and (ii) increased by the Department at the end of
the post -closure monitoring and care period if there are statistically significant increasing groundwater quality trends or if contaminant concentrations have not decreased to a level protective of public health, safety, and welfare;
k
the environment; and natural resources. If the owner determines that the post -closure care monitoring and care period is no longer needed and the Department agrees, the owner shall provide a certification, signed and sealed by
11
a professional engineer, verifying that post -closure monitoring and care has been completed in accordance with the post -closure plan. If required by Chapter 89C of the General Statutes, the proposed plan for post -closure
monitoring and care should be signed and sealed by a professional engineer. The plan shall include, at a minimum, all of the following:
1
A demonstration of the long-term control of all leachate, affected groundwater, and stormwater.
11.1
A description of a groundwater monitoring program that includes (i) post -closure groundwater monitoring, including parameters to be sampled and sampling schedules; (ii) any additional monitoring well installations, including a map
2
with the proposed locations and well construction details; and (iii) the actions proposed to mitigate statistically significant increasing groundwater quality trends.
11.2
I.
An estimate of the milestone dates for all activities related to closure and post -closure.
12.1
M.
Projected costs of assessment, corrective action, closure, and post -closure care for each coal combustion residuals surface impoundment.
12.2
A description of the anticipated future use of the site and the necessity for the implementation of institutional controls following closure, including property use restrictions, and requirements for recordation of notices
n
documenting the presence of contamination, if applicable, or historical site use.
6.2
Page 2

AECOM Table 2-1: NC CAMA Closure Plan Requirements September 20, 2019
Summary and Cross Reference Table
Duke Energy, Allen Steam Station
Corresponding
No.
Description
Closure Plan Section
§ 130A-309.214(b)(3) No later than 60 days after receipt of a proposed Closure Plan, the Department shall conduct a public meeting in the county or counties proposed Closure Plan and alternatives to the public.
Note 1
Reports Prepared by Other Consultants Include:
1 Synterra Groundwater Assessment Work Plan
2 HDR Groundwater Assessment Work Plan
Page 3

AECOM
Duke Allen Steam Station
Closure Plan
Table 4-1 - Summary of Geotechnical Index Properties'
Ash Within Ash Basin
Properties
(RAB and AAB)
Foundation Soil below Ash Basin
Embankment Fill Soil
Foundation Soil below Embankment Dam
Partially Weathered Rock (PWR)
Silt (ML), Silty Sand (SM), Sandy Silt (ML), and
Sandy Silt (ML / MH), Sandy Clay (CL / CH),
Silty Sand (SM), Sand (SW), Clayey Sand
Silty Sand (SM), Sandy Silt (ML), Sand (SC),
Soil Type
Silt/Sandy Silt (ML) - Predominantly Fly Ash,
Clay (CH)
Silt (ML), Silty Sand (SM), and Clayey Sand
(SC), Sandy Clay (CL / CH), Clayey Silt (ML),
and Clay (CL)
(SC)
and Sandy Silt (ML)
Liquid Limit
Non -Plastic
NP - 49%
NP - 73%
NP - 68%
NP - 33%
Plasticity Index
Non -Plastic
NP - 35%
NP - 39%
NP - 35%
NP - 8%
Representative
Geometric Mean
Representative
Geometric Mean
Representative
Geometric Mean
Representative
Geometric Mean
Representative
Geometric Mean
Range
Range
Range
Range
Range
Natural Moisture Content (%)
18 - 66
39
11 - 68
29
12 - 69
27
4 - 67
30
11 - 24
16
Fines Content
15 - 98
68
17 - 89
50
13 - 81
57
19 - 90
49
21 - 64
34
Moist Unit Weight - y,n (pcf)
72 - 120
92
74 - 113
98
115 - 149
126
115 - 133
124
---
---
Dry Unit Weight - 7a (pcf)
57 - 92
68
55 - 86
71
87 - 119
99
91 - 114
103
---
Specific Gravity
1.95 - 2.81
2.23
2.53 - 2.95
2.75
2.59 - 2.79
2.68
2.66 - 3.08
2.76
2.68 - 2.94
2.78
Notes:
NP: Classification of Non -Plastic
*Only one lab test data available
Data obtained from lab tests performed on material obtained from within the Ash Basins for the Closure Design, Phase 2 Reconstitution of Ash Pond Designs Report (AECOM, 2016a), Allen Geotechnical and Design Services Report (S&ME, 2010), Site Suitability
Study Retired Ash Basin (S&ME, 2007), Comprehensive Site Assessment Study by (HDR, 2015a), and Historical geotechnical data provided by Duke Energy.

Table 10-1
Allen Steam Station Regulatory Permits, Approvals, or Requirements for Ash
Basin Closure by Excavation
Permit/Approv
al
Type of
Existing
Regulatory
Permit
Approval
General Permit
Regulating
No.
Mechanism or
Name or Subject
Agency
applicable)
Not Required
Comments
Permit modification likely due to the
Permit
increased heavy equipment vehicle
Air Quality
NCDEQ
modification
traffic and potential dust generated
likely
during closure activities
Gaston
A local building permit is required for
Building Permit
New Permit
County
installation of construction trailers
Modification or abandonment of CAMA
CAMA Monitoring
Written NCDEQ
program monitoring wells require the
Plan
NCDEQ
DWR approval
approval of the Division of Water
Resources (DWR)
CCR
Impoundment
US EPA
Self -Regulating
Required postings to Public Record
CCR Rule
Closure
CCR
Maintain CCR GW monitoring network
Impoundment
US EPA
Self -Regulating
and requirements as stated in 257.90 -
Monitoring
CCR Rule
Network
257.98
USACE
and
NCDEQ
It is anticipated that an individual
Clean Water Act
DWR 401
Individual
permit will be required in relation to
401
Water
Permit
dam breaching and associated
Quality
downstream impacts.
Permitting
Section
It is anticipated that an individual
Clean Water Act
Individual
permit will be required in relation to
404
USACE
Permit
dam breaching and associated
downstream impacts.
Applicable and
Erosion and sediment controls, natural
to be covered
Cutting Trees
habitat, and endangered species
as part of other
considerations.
permits

AAB Dam - Permitting is required to
Certificate of
modify or abandon wells and
Dam Safety
NCDEQ
GASTO-
Approval to
instrumentation on regulatory dams
061
Modify
through the Division of Energy, Mineral,
and Land Resources (DEMLR)
AAB Dam - Final approval after
abandoning wells and instrumentation
Certificate of
on regulatory dams through the
Dam Safety
NCDEQ
GASTO-
Final Approval
Division of Energy, Mineral, and Land
061
(COFA)
Resources (DEMLR) in accordance with
the Dam Safety Law of 1967, 15A WAS
02K.0220.
AAB Dam - Permitting is required to
modify and remove the dam in
Certificate of
accordance with the Dam Safety Law of
GASTO-
Approval to
1967, § 143-215.27 and § 143-215.27A
Dam Safety
NCDEQ
061
Modify and
(where applicable) and the Dam Safety
General Provisions, 15A WAS 02K.0201
Remove
(b)(2); an application must be filed with
the Division of Energy, Mineral, and
Land Resources (DEMLR)
AAB Dam - Final approval after
Certificate of
modifying to remove the Ash Basin
Dam Safety
NCDEQ
GASTO-
Final Approval
Dam through the Division of Energy,
061
(COFA)
Mineral, and Land Resources (DEMLR)
in accordance with the Dam Safety Law
of 1967, 15A WAS 02K.0220.
RAB Dam - Permitting is required to
Certificate of
modify or abandon wells and
Dam Safety
NCDEQ
GASTO-
Approval to
instrumentation on regulatory dams
016
Modify
through the Division of Energy, Mineral,
and Land Resources (DEMLR)
RAB Dam - Final approval after
abandoning wells and instrumentation
Certificate of
on regulatory dams through the
Dam Safety
NCDEQ
GASTO-
Final Approval
Division of Energy, Mineral, and Land
016
(COFA)
Resources (DEMLR) in accordance with
the Dam Safety Law of 1967, 15A WAS
02K.0220.
RAB Dam - Permitting is required to
Certificate of
modify and remove the dam in
GASTO-
Approval to
accordance with the Dam Safety Law of
Dam Safety
NCDEQ
016
Modify and
1967, § 143-215.27 and § 143-215.27A
(where applicable) and the Dam Safety
Remove
General Provisions, 15A WAS 02K.0201
(b)(2); an application must be filed with

the Division of Energy, Mineral, and
Land Resources (DEMLR)
RAB Dam - Final approval after
Certificate of
modifying to remove the Ash Basin
Dam Safety
NCDEQ
GASTO-
Final Approval
Dam through the Division of Energy,
016
(COFA)
Mineral, and Land Resources (DEMLR)
in accordance with the Dam Safety Law
of 1967, 15A NCAS 02K.0220.
Utilization of or modification to state or
DOT - General
Not anticipated
federal highways to transport CCR will
at this time
require consultation or notification to
relevant DOT agency
Driveway Permit
NCDOT
Potential
Temporary access or driveway permits
as needed
Land disturbance activities outside of
the ash basin will exceed one acre,
therefore in conformance with 15A
Erosion and
NCAC 04, an E&SC Permit is required
Sediment Control
NCDEQ
New Permit
from Land Quality prior to
(E&SC)
commencement of construction in
those areas. Note that land
disturbance includes tree clearing and
grubbing and vehicular wheel or
tracking as disturbance.
Removal from or import of material
Fire Ants
Restriction not
could be restricted dependent on the
likely
potential for fire ants and geographic
regions involved
Gaston County Floodplain Development
Regulations Section 16.3.3 require a
Floodplain
Gaston
Floodplain Development Permit prior to
Development
County
New Permit
the start of construction within FEMA-
mapped Special Flood Hazard Areas
indicated on Flood Insurance Rate
Maps.
Permits are required to construct any
water supply well or water well system
Large Capacity
NCDEQ
New Permit
with a design capacity equal to or
Water Supply Well
possible
greater than 100,00 gallons per day -
for dewatering outside of the ash basin
Multi -State
If movement of CCR will cross state
Not required
lines, multi -state regulations might
Agreement
apply

NPDES (National
Pollution
Permit
Modification of NPDES may be
Discharge
NCDEQ
NC0004
modification
necessary if new source or outfall is
Elimination
979
likely
created.
System)
NPDES (National
Pollution
Discharge
NCS000
Permit revision
Revision to existing sitewide permit or
NCDEQ
new permit may be required for access
Elimination
546
likely
System) Industrial
roads, staging areas, etc.
Stormwater
Removal from or import of vegetated
Not anticipated
material could be restricted dependent
Noxious Weeds
at this time
on the vegetation and geographic
regions involved
Railroad
Not
Construction activities adjacent to
Easement, Access,
anticipated at
tracks/ballast or a new railroad crossing
or Crossing Permit
this time
require an agreement or permit
SPCC (Spill
In accordance with the Federal Water
Prevention
Modification of
Pollution Control Act (Clean Water Act)
Control and
EPA
Countermeasure)
existing plan
of 1974, Title 40, Code of Federal
Regulations, Part 112.
Plan
Threatened or
Endangered
Species:
Candidate
Federal and/or state regulations may
Conservation
apply including agency consultation and
Agreement
performing site -specific surveys within
Avian Protection
NCDEQ
the proper survey period (e.g.,
Plan(s)
and EPA
flowering period for listed plant) to
Bird and Bat
determine if Threatened or Endangered
Conservation
Species or their habitat exist within the
Strategies
limits of disturbance
Eagle
Conservation Plan
Eagle Take Permit
Solid Waste Site
Approval by
NCDEQ
New CCR Landfill
Suitability
Letter
Solid Waste
Permit to
NCDEQ
Permit
New CCR Landfill
Construct
Solid Waste
NCDEQ
Permit
New CCR Landfill
Permit to Operate