NC0004979_Fact Sheet Amendment_20051031

NCDENR/DWQ
FACT SHEET AMENDMENT
Duke Energy.Corp®ration - Allen Stearn Station
NC0004979 .
l ' $ iiT �"" F t t 4 .A"k�'K =���cg. -�"� C { 5' Sik +�w/'}♦ /y 'y�ye"v }/'i f 6 y�`(^b� .{i�.3 '�f `#^ ,C'€ �':.. Z . nr 9,. '
(1.) Facility Name:
j Allen Steam Station
4
(2.) Permitted Flo
—
1 No o flow limit (6.) County 1 Gaston �—
(3.) Facility Class: —
y_ I — (7J Regional Office:
Mooresville
(4.) Pretreatment Program:
j N/A (8.) USGS Topo Quad:
—_
G14NE
(5.) Permit Status:
Renewal (9.) iJSGS Quad Name:
_ - — -
Belmont
411 � h^ 3 �`� �vx, � 4 4.y £ -:�"n✓+R d R 4H3 k "4 .Y "3g+d'gy " 4' RFs t�i�5', x
� a irs��,�.� �;
a:. �" #� �+ + � r j}�paye�^yq yp� m i •�j.��}ry�� r�j,���7�rz.
� e.
�"r � z�. 2 � ��,:. r>rz' i� a°�.4 �.
Y`�,zSr-?` ,a.:,.,.a. xb'�r:n�2'�wB�.Lia....;�•.�F'i'.
t
s'�K+a..rs^yy�6J4.iclAA1LcA�.C`kG156R1.O%i13;
(1.) Receiving Stream:
Catawba /
(7.) Drainage Area (mi?):
' ??/635
South Fork
Catawba Rivers
(2.) Sub -basin:
t 03.08^34
(8.) Summer 7Q10 (cfs),:
L__
i 95/12n
_.._.
(3.) Stream Index Number:
_
11-123.5
( (9.) Winter 7Q10 (cfs):
95/22%
(4.) Stream Classification:
_
j WS -V B .^1
(10.) 30Q2 (cfs):
j 314i/� -9
(5.) 303(d) Status:
i Not listed
(11.) Average Flow (cfs):
06
(6.) 305(b) Status:_.__...__
-
j (12.) IWC %:
-2,4702;` .....___.___...__..__..
24 (0'u f fall 002)
Notes:
1. 30Q2 for the Catawba River has been defined as the minimum daily average release at Mou: , tain Island
Hydro.
2. Average flow (QA) for the Catawba River has been defined as mean annual flow based on cr.c!rations
records from 1929 to 2003 at Mountain Island Hydro.
1.0 Proposed Changes Incorporated Into. Permit Renewal
• Add language allowing the construction of the FGD system and the dry ash. ) Candling system.
• Add monitoring requirements at internal outfall 005 (treated FGD wet scrut,her wastewater to
ash settling basin).
• Remove arsenic limit and monitoring requirement due to lack of reasonable ;>otential for
levels of this parameter to cause an exceedance of water quality standards.
• Add 3 -year compliance schedule for 21 pg/L selenium limit to coincide with the estimated
completion date of the dry ash handling system.
2.0 Summary
Selenium Compliance Schedule
During the comment period, Duke Power and Division staff met to discuss several proposed
changes to the draft permit. The primary point of concern involved .the increase in IWC and the
resulting change in permit limits (particularly selenium). Duke indicated that at this time they
would have difficulty meeting the selenium limit, however they will be installing a dry ash
handling system that is expected to cut flows in half. Since the IWC calculation is based on actual
flows, a reduction in flow would decrease the IWC and therefore increase the allowable selenium
limit. Duke has asked Division staff to allow 3 years for the construction of the treatment system
before the 21 ug/L selenium limit takes effect. Until that time, the existing limit of 31 pg/L will
remain in the permit.

NPDES Permit Amendment - 06/28/
Page 2
Removal of Arsenic Limit
During the cornment period, Duke i
was recalcula ak-d using 30Q2= 314 (1
license) and Q,`•: -= 2470 cfs (mean ar
Hydro). Based ;-i this data, there is
water quality s: idards. The RPA)
and aj z allowal, concentration of 8
be removed.
Duke Power/ Allen Steam Station
NC0004979
s able to provide updated 30Q2 and QA values. The RPA
umum daily average release as defined in the FERC
Cal flow based on 1929-2003 data for mountain Island
> longer reasonable potential for an exceedance of arsenic
[ded a maximum predicted concentration of 203.5 Vg/L
pg/L. The arsenic limit and monitoring requirements will
Constru ion of
e Gas Desulfurizatioi' and Dry Ash Handling Systems
Duke) i,is to.
all two major pollu ion control systems at Allen Steam Station in 2009: a Dry
Ash 11 Cling
tem and a Flue Gas Desulfurization (FGD) system. The Dry Ash Handling
system fl de,
se the flow and pollutant loading to the ash basin (Outfall 002). The FGD
system 11 int
uce an additional Wastewater stream that will be treated by a dedicated
wastev -r tr(
lent system (WWT9). Effluent from the WWTS will discharge to the ash basin,
-here .• itio)
reatment will occulprior to discharge. Once both systems are installed, the
i'rnw rat( om
ash basin is expect d to be reduced by approximately 50%.
1 ..e pro,, iec� )ected pollutant
c 11. In so � ie s tions, literature
D, D sites.
trations based primarily on models and the analysis of
h was used along with analytical results from current

NPDES Permit Amendment - 06/28/06
Page 3
Flue Gas Desulfurization Wastewater Characteristics
Duke Power/ Allen Steam Station
NC0004979
Potential
Parameters of
Concern
Projected
Average
concentrations
in FGD
wastewater
(pg/L)
Projected
Concentrations
after WWTS
(pg/L)
Projected
Average
Concentrations
at Outfall 002
(pg/L)
Applicable
Water
Quality
Standards
(pg/L)
Antimony
0.02
0.01
0.01
5.6E
Arsenic
0.28
<0.14
0.14
10C
Barium
4.9
<2.5
0.52
1000
Beryllium
0.035
<0.02
<0.0005
0.0068c
Boron
20
10
1.54
750E
Cadmium
O.U7
0.035
<0.0005
15.OA
COD
450
225
31
Chloride
2997
1499
184
250000
Chromium
0.40
0.20
0:06
1022A
Cobalt
0.37
0.18
<0.030
Copper
0.44
0.22
0.04
7.3A
Fluoride
52.2
26.1
3.46
1800
Lead
0.30
0.15
0.02
33.8A
Manganese
5.74
2.8
0.40
200
Mercury
0.35
0.0005
<0.0001
0.01.2
Molybdenum
0.43
0.21
0.07
-
Nickel
0.70
0.40
0.06
261A
Selenium
6.9
0.05
0.01
56A
Silver
O.07
0.03
<0.005
1.23A
Sulfate
1500
750
142.1
250000
Temperature
133 OF
95 OF
Ambient
Narrative
Thallium
0.22
0.11
0.01
0.35E
TSS
16000
15
10
-
Vanadium
0.21
0.11
0.01
24E
Zinc
0.37
0.18
0.04
67A
C= carcinogen
A= acute criteria
E= EPA criteria
Duke has received permit modifications at several other plants for the addition of FGD systems.
Each of those has received monthly flow monitoring as well as weekly monitoring at an internal
outfall (discharge to ash basin) for the following parameters:
TSS ® Chloride 8 Silver
• Arsenic o Mercury m Zinc
• Cadmium o Nickel
• Chromium • Selenium
In addition, the following appear to be potential pollutants of concern at this facility and will also
be monitored:
Beryllium
• COD

NPDES Permit Amendment — 06/28/
Page 4
Duke Power/ Allen Steam Station
NC0004979
4.0 Proposed Schedule for Permit Issuance
Draft Permit to Public Notice: TBD
Permit Scheduled to Issue: TBD
5.0 State Contact Informatio
If you have any questions on any of tie above information or on the attached permit, please
contact Toya Fields at [phone], I xtension 551.
ed t� provide further•information on the permit development:
Copies of the following are attach p p p
® Draft permit
NPDES
Signature I Date
Regional Office Comments:
Regional Recommendation by:
Signature ����`�
Date��
Reviewed and accepted by:
Regional Supervisor:
Signature
Date
NPDES Unit Supervisor:
Signature
Date

, 5
t
REASONABLE POTENTIAL ANALYSIS
Allen Steam Station
NC0004979
Time Period 2002-2005
Qw (MGD)
18.9
7Q10S(cfs)
95
7Q 10W (cfs)
95
30Q2 (cfs)
314
Avg. Stream Flow, QA (cfs)
2470
Rec'ving Stream Catawba River
WWTP Class I
IWC (%) @ 7Q10S
23.569
7Q 10W
23.569
@ 30Q2
8.5335
® QA
1.1721
Stream Class WS -IV B
Outfall 2
Qw = 18.9 MGD
Legend:
C = Carcinogenic
NC = Non -carcinogenic
A = Aesthetic
Freshwater Discharge
4979_rpa.xls, rpa
12/14/2005
STANDARDS &
PARAMETER
TYPE
CRITERIA (2)
POL
Units
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
(1)
NCWOS/ Vi FAV/
n #&L Mar Prod GW Allowable Cw
Chronic Acute
Acute: WA
Arsenic
C
10
ug/L
42 42
203.5
'
Chronic: 853
Max predicted «allowable
Acute: N/A
-
Barium
NC
1000.0
ug/L
9 9 691.2
'
Note: n<12
................
----------'
Chronic: 4,243
------------------------------_.
Max predicted «:allowable
Limited data set
Remove monitoring
Acute: 15
Cadmium
NC
2 15
ug/L
13 8
3.3
----------------------------------------------
Chronic: 8
Max predicted << allowable.
Remove monitoring
Acute: 1,022
-
Chromium
NC
50 1,022
ug/L
14 1
61.6
..............................................
Chronic: 212
Max: predicted <<
Removemonitoring '
Acute: 7
--
Copper
NC
7 AL 7.3
ug/L
79 76
117.9
Chronic: 30
max predicted » allowable. Action level. parameter
limit required by 40. CFR 423.12'
Acute: 22
Cyanide
NC
5 N 22
10
ug/L
12 3
5.0
---------------------------------------------
________________Chronic:
Chronic:21
max predicted << allowable.
Remove monitoring '
Acute: N/A
Iron
NC
1 AL
mg/I
52 52
2.4
----------------------------------------------
_________________Chronic:
Chronic: 4
Max predicted , allowable
limitrequired by 40. CFR 423.12
Acute: WA
Napthalene
NC
570
ug/L
19 1
13.9
Chronic: 2,418
Max predicted << allowable
Remove monitoring
Acute: A--
Nickel
Nickel
NC
25
ug/L
12 12
47.9183
---------------------------------------
_____________Chronic: 106
Chronic:
Max predicted << allowable
Remove, monitoring
Acute: N/A
,..
Phenols
A
1 N
ug/L
19 0
5.0
_______________
-----------------------------------
Chronic: 12
No detections.
Remove monitoring
Acute: 56
Selenium
NC
5 56
ug/L
80 80
58.6
—_—_—_—_—_—_
Chronic: 21
_—_—_—_—_—_—_—_-----_—_—_—_—_--
Several values above the allowable in 2003
Retain limit
Acute: 67
...
' Zinc
NC
50 AL 67
ug/L
13 13
79.1
_ _ __ _ __
Chronic: 212
_ _
Max .rpedicted«allowable
Remove monitoring
Acute: WA
Sulfates
NC
250.0
mg/L
13 13
96.4
Chronic: 1,061
Max predicted <,allowable ,
Remove monitoring
Acute: N/A
0 0
N/A
_ --------------------------------------
Chronic: °rro- Type
-------------- ---------------
Acute: N/A
0 0
N/A
Chronic:: --- Type -------------------------------
rror
Legend:
C = Carcinogenic
NC = Non -carcinogenic
A = Aesthetic
Freshwater Discharge
4979_rpa.xls, rpa
12/14/2005

7
r -
n N N m O m N
Omi V N ^Nm
O a O
nm
N
II U
o j �
U d
7Q C LL1a.
y
2iniU c rL ��
O Oi N m N Oi Oi N O
N N N N t0 N r m
J
O
fL
W h m N V N V W N
N N N
m
O� Nm '7 w m n m W n 0 N M a m m n W O� O N M a m W m m 0
- �- •- � � � r � �- N N N N N N N N N N M t7 MMM M M M M M V a 'd' d' V O V? 7 �} to
N n C O m N
6 c6
(m0 QMi tW0 h N
M N
u Z5 0 U
O c i > d
man>U c ami
J 7 r M N q O a W m N r N M m m m n N O W m M I*� m N W m N 7 r W N V m m O m O h 0 7 m
N O, N 0 N m I: m m C m N N N N m m a V N r T M N m I' a f' m Ih ' r m N r m a N m t2 ' w?
J
O
m
O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
y N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N N ,.
m m � rn o n v C� t0 t7 a 4 C FD M n 9 Q n a � N Q. C N - -
�c��v�n�onmrnolc�.-cl. ��mm�m�o�c��c�Ma�nconcornoTc1� c�a�mm�
a N m n m OI O N M V N W h m m 0 N Main m n m O� O N M �t N m n m m O N M m m n W W O N M a m m n m rn o N M a W m n m O! O
.- � �-- .- �- �- N N N N N N N N N N M M M M M M M M M M V a a V VR C C a V m m to m �n in �n m m m m co m m m m m m m m h n n n n n n l� n h m ao

r r

REASONABLE POTENTIAL ANALYSIS
4979_rpa.xls, data
2- 12/14/2005
Cadmium
Chromium
Date
Data
BDL=1/2DL
Results
Date Data
BDL=1/2DL
Results
Date Data
1 1/7/2003
< 0.5
0.3
Std Dev.
0.3185
1
2/5/2002 <5
40
20.0
Std Dev.
5.3452
1
7/1/2003 <'
5'
2 7/1/2003
< 0.5
0.3
Mean
0.5531
2
5/7/2002 <
40
20.0
Mean
21.4286
2
8/9/2003 <
- 2
3 10/7/2003
`< 0.5
0.3
C.V.
0.5759
3
7/2/2002
40
40.0
C.V.
0.2494
3
9/10/2003 <#
5
4 1/6/2004
<, 0.5
0.3
n
13
4
10/1/2002 d%
40
20.0
n
14
4
1/2/2002
11
5 1/4/2005
,<:: 0.5
0.3
5
1/7/2003 <':
40
20.0
5
2/5/2002 ;;f
11
6 7/2/2002
:-- ` 0.63
0.6
Mult Factor =
2.6200
6
7/1/2003,-{
40
20.0
Mult Factor =
1.5400
6
3/5/2002, ' e
16
7 10/1/2002
0.53
0.5
Max. Value
1.3 ug/L
7
10/7/2003[<'
40
20.0
Max. Value
40.0 ug/L
7
4/2/2002 ¢
10
8 4/1/2003
0.59
0.6
Max. Pred Cw
3.3 ug/L
8
1/6/20041,<9
40
20.0
Max. Pred Cw
61.6 ug/L
8
5/7/2002, f
7
9 4/6/2004
€ 0.59
0.59
9
4/6/200411<
40
20.0
9
5/14/2002{ , #
17
10 7/6/2004
1.25
1.25
10
7/6/20041�
40
20.0
10
5/15/2002 %
18
11 10/5/2004.
0.52
0.52
11
10/5/2004 <
40
20.0
11
5/16/2002 _.
16'
12 4/5/20055,
0.92
0.92
12
1/4/20051<,
40
20.0
12
6/4/2002:
12
13 7/5/2005
0.91
0.91
13
4/5/2005 c
40
20.0
13
7/2/2002 's
-16.
14
14
7/5/2005 ,S
40
20.0
14
7/16/2002 -
17
15
15,
15
8/6/2002
10
16
A16
16
8/21/2002
7
17
4
17
17
9/3/2002
8
18
5
18
18
9/17/2002
6
19
19
_.
19
10/1/2002=
11.
20
20'
20
10/15/2002
8
21,
q
21-
21
11/5/2002-
16
22
22
22
11/19/2002
11
23
g
23
23
1/7/2003
9
24
8
24'
24
1/21/2003
6
25
25
'�
25
2/4/2003 ' <
22'.
26
26
26
2/18/2003 y(
9
27
27
27
3/4/2003 #
14
28'
28
28
3/18/2003' B
7
29'
30
29'
30�?
,#
29
30
4/1/2003 1
4/15/2003.
16
13.
31
31
31
5/6/2003444, .,888
6
32
" €
32
32
5/20/2003
4
33
33.
33
6/3/2003
8
34
,°
34�
g ¢
34
6/17/2003,
4
35
�(
35
35
7/15/2003t
4
36
36-
36
8/26/2003
2
37
37•
-
37
9/24/2003 ..
3
38
38'
38
10/7/2003
8
39
39
#
39
10/21/2003
6
40
40.
;' ,.
40
11/4/2003e 1
7
41
41
g
41
11/18/2003
10
42
42
# -'
42
12/2/2003 '
21
43
1.
43'
43'
12/15/2003 .'
5'
44
44
I-�,
44
1/6/2004.-
8.
45
l
45
45
1/20/2004 ,
14
46
E
46.
46
2/3/2004
26
47
_
#
47•
47
2/17/2004:
18
48
48,
48
3/2/2004
6
49
;,
49,
49
3/16/2004
4
50
50.
'^
50
4/6/2004 '
6'
51
51
51
4/20/2004
4
52,
52'
52
6/1/2004
11
53
53:
53
6/15/2004
10
54
54
-
54
7/6/2004 "
21
55
55
55
7/20/2004 ' '
"
4
56
56
56
8/3/2004
7
57
g
57
57
8/17/2004
6
58
58
-
58
9/7/2004
6'
59
I1
59
59
9/21/2004! €
24
60
60
60
10/5/2004
18
61
61
61
10/19/2004
14
62
62'
62
11/3/2004 "
18.
63
63;
63
11/16/2004'
27
64,
64
3
64
12/7/2004 "�
10.
65'
( %'
65•
65
12/20/2004
8
66
t
66
66
1/4/2005
-6
67
67
67
1/18/2005
6
68
68
68
2/1/2005 r
43
69
E
69
69
2/15/2005
40
70
70
{
70
3/1/2005
54
71
`
71
#
71
3/15/2005 {
43
72
LA
72
2
72
4/5/2005
67
73
73�
73
4/19/2005
13
74
74
.1
74
5/3/2005
20
75
k
75
y s
75
5/17/2005 s
31
78
3
76
� �
76
6/7/2005 j . J�
29
77
3
77
77
6/21/2006
8
78
l E
78
78
7/5/2005
49
79
79
(
79
7/19/2005 1
43
80
1
80-
80
81
� _i
81
i s
81
1
4979_rpa.xls, data
2- 12/14/2005

Copper
BDL=1/2DL
Results
Results
2.5
Std Dev.
12.7816
1.0
Mean
14.4304
2.5
C.V.
0.8857
11.0
n
79
11.0
2
5.0
16.0
MultFactor=
1.7600
10.0
Max. Value
67.0 ug/
7.0
Max. Pred Cw
117.9 ug/
17.0
2
5.0
18.0
5.0 ug/
2
16.0
Max. Pred Cw
5.0 ug/
12.0
5.000
0.1
16.0
2
5.000
17.0
2
10.0
0.2
7.0
5.000
0.1
8.0
2
5.000
6.0
0.1
11.0
1.1
8.0
0.1
16.0
0.1
11.0
0.1
9.0
0.3
6.0
0.2
22.0
0.0
9.0
0.1
14.0
0.1
7.0
0.1
16.0
0.2
13.0
0.1
6.0
0.7
4.0
0.7
8.0
0.2
4.0
0.3
4.0
2.0
3.0
8.0
6.0
7.0
10.0
21.0
5.0
8.0
14.0
26.0
18.0
6.0
4.0
6.0
4.0
11.0
10.0
21.0
4.0
7.0
6.0
6.0
24.0
18.0
14.0
18.0
27.0
10.0
8.0
6.0
6.0
43.0
40.0
54.0
43.0
67.0
13.0
20.0
31.0
29:0
8.0
49.0
43.0
REASONABLE POTENTIAL ANALYSIS
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15:
16
17 ,
18
19
20
21
22
23 `
24
25.
26
27
28
29
30
31
32
33
34'
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62'
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
-3-
Date Data
1 1/2/2002 ` 0.1
2 1/15/2002 0.1
3 2/5/2002{ 0.3
4 2/19/2002'P:' 0.0
5 3/5/2002 0.1
6 3/19/2002; 0.21
7 4/2/2002 0.
8 4/16/2002 ":6' 0.1
9 5/7/2002" 0.0
10 5/14/2002 = : 0.
11 5/15/2002,' 0.2
12 5/16/2002 0.1
13 5/22/2002 0.1
14 6/4/2002 , 0.1
15 6/18/2002 0.11
16 7/2/2002 " 0.0
17 8/6/2002.'. 0.0
18 9/3/2002 i, 0.1
19 10/1/2002 0.0
20 11/5/2002 0.0
21 12/2/2002 0.0
22 1/7/2003 0.
23 2/4/2003 0.1
24 3/4/2003 '> 0.1
25 4/1/2003 I" 0.1
26 5/6/2003 ,�;� 0.1
27 6/3/2003 < 0.7
28 7/1/2003 0.0
29 8/9/2003 I' 1.0
30 9/10/2003 ' 0.81
31 10/7/2003 £ 0.09
32 11/4/2003'- F 0.1
33 12/2/2003 ';;;[ 0.0
34 1/6/2004 ` 4': 0.09
35 2/3/2004 ` ` 0.34
36 3/2/2004 :;; 0.06
37 4/6/2004: 0.15
38 5/4/2004 7=.- 0.04
39 6/1/2004 0.05
40 7/6/2004'' 0.1
41 8/3/2004 _: ;5 0.05
42 9/7/2004 0.06
43 10/5/2004 a 0.14
44 11/3/2004 0.19
45 12/7/2004 „ 0.18
46 1/4/2005 ` ' € 0.08
47 2/1/2005: l 0.69
48 3/1/2005 0.61
49 4/5/2005 ' 0.71
s
50 5/3/2005 s 0.24
51 6/7/2005 "'' 0.1
52 7/5/2005 '• ° 0.31
53
54
55
56 [
57 1
58
59
60 ..;.`.
61 1
62
63
64
65
66
67 ;'..
68
69
70
71
72
73
74,s
75
76 f
77
78
79
80 `-
81
Iron
BDL=1/2DL
7
4
7
9
2
3
2
9
3
3
4
5
3
6
7
7
2
8
4
2
3
7
6
7
BDL=1/2DL
Results
Std Dev.
2
5.0
Std Dev.
0.0000
0.1
n
Mean
5.0000
2
5.0
C.V.
0.0000
2
5.0
n
12
2
5.0
0.2
2
5.0
Mult Factor=
1.0000
2
5.0
Max. Value
5.0 ug/
2
5.0
Max. Pred Cw
5.0 ug/
2
5.000
0.1
2
5.000
0.1
2
5.000
0.2
2.5
5.000
0.1
2
5.000
0.7
-3-
Date Data
1 1/2/2002 ` 0.1
2 1/15/2002 0.1
3 2/5/2002{ 0.3
4 2/19/2002'P:' 0.0
5 3/5/2002 0.1
6 3/19/2002; 0.21
7 4/2/2002 0.
8 4/16/2002 ":6' 0.1
9 5/7/2002" 0.0
10 5/14/2002 = : 0.
11 5/15/2002,' 0.2
12 5/16/2002 0.1
13 5/22/2002 0.1
14 6/4/2002 , 0.1
15 6/18/2002 0.11
16 7/2/2002 " 0.0
17 8/6/2002.'. 0.0
18 9/3/2002 i, 0.1
19 10/1/2002 0.0
20 11/5/2002 0.0
21 12/2/2002 0.0
22 1/7/2003 0.
23 2/4/2003 0.1
24 3/4/2003 '> 0.1
25 4/1/2003 I" 0.1
26 5/6/2003 ,�;� 0.1
27 6/3/2003 < 0.7
28 7/1/2003 0.0
29 8/9/2003 I' 1.0
30 9/10/2003 ' 0.81
31 10/7/2003 £ 0.09
32 11/4/2003'- F 0.1
33 12/2/2003 ';;;[ 0.0
34 1/6/2004 ` 4': 0.09
35 2/3/2004 ` ` 0.34
36 3/2/2004 :;; 0.06
37 4/6/2004: 0.15
38 5/4/2004 7=.- 0.04
39 6/1/2004 0.05
40 7/6/2004'' 0.1
41 8/3/2004 _: ;5 0.05
42 9/7/2004 0.06
43 10/5/2004 a 0.14
44 11/3/2004 0.19
45 12/7/2004 „ 0.18
46 1/4/2005 ` ' € 0.08
47 2/1/2005: l 0.69
48 3/1/2005 0.61
49 4/5/2005 ' 0.71
s
50 5/3/2005 s 0.24
51 6/7/2005 "'' 0.1
52 7/5/2005 '• ° 0.31
53
54
55
56 [
57 1
58
59
60 ..;.`.
61 1
62
63
64
65
66
67 ;'..
68
69
70
71
72
73
74,s
75
76 f
77
78
79
80 `-
81
Iron
BDL=1/2DL
7
4
7
9
2
3
2
9
3
3
4
5
3
6
7
7
2
8
4
2
3
7
6
7
Results
0.2
Std Dev.
0.1
Mean
0.4
C.V.
0.1
n
0.1
0.2
MultFactor=
0.3
Max. Value
0.1
Max. Pred Cw
0.1
0.3
0.2
0.1
0.1
0.1
0.1
0.1
0.0
0.1
0.1
0.1
0.1
0.2
0.2
0.1
0.1
0.1
0.7
0.1
1.1
0.8
0.1
0.1
0.1
0.1
0.3
0.1
0.2
0.0
0.1
0.1
0.1
0.1
0.1
0.2
0.2
0.1
0.7
0.6
0.7
0.2
0.1
0.3
4979_rpa.xls, data
12/14/2005

REASONABLE POTENTIAL ANALYSIS
4979_rpa.xls, data
- 4 - 12/14/2005
Napthalene
Nickel
Date
Data
BDL=1/2DL
Results
Date Data
BDL=1/2DL
Results
0.2244
1 1/2/2002
10
5.0
Std Dev.
1.1471
1
7/2/2002 ,
18.37
18.4
Std Dev.
5.5846
1
0.2083
2 2/5/2002
< 10
5.0
Mean
5.2632
2
10/1/2002
15.79
15.8
Mean
17.3667
2
1.0774
3 3/5/2002'<.
10
5.0
C.V.
0.2179
3
1/7/2003
13.7
13.7
C.V.
0.3216
3
52
4 4/2/2002<
10
5.0
n
19
4
4/1/2003
18.26
18.3
n
12
4
5 5/7/2002
K' 10
5.0
5
7/1/2003 '.
13.53
13.5
5
2.3100
6 6/4/2002
s1 10
5.0
Mult Factor=
1.3900
6
10/7/2003, ---
10.51
10.5
Mult Factor=
1.79
6
1.1 mg/I
7 7/2/2002
:-- 10
10.0
Max. Value
10.0 ug/L
7
4/6/2004-.
16.58
16.6
Max. Value
26.8 ug/L
7
2.4 mg/l
8 10/1/2002
r: 10
5.0
Max. Pred Cw
13.9 ug/L
8
7/6/2004
26.64
26.6
Max. Pred Cw
47.9 ug/L
e
9 1/7/2003
10
5.0
9
10/5/2004-:
17.58
17.6
9
10 4/1/2003�<:::.,
10
5.0
10
1/4/2005 :
9
9.0
10
11 7/1/2003i'<'
10
5.0
11
4/5/2005F
21.67
21.7
11
12 10/7/2003
e-: 10
5.0
12
7/5/2005' ,
26.77
26.8
12
13 1/6/2004
< 10
5.0
13'
13
14 4/6/2004
< 10
5.0
14
14
15 7/6/2004
S11 10
5.0
15
15
16 10/5/2004
< 10
5.0
16
16
17 1/4/2005
<: 10
5.0
17'
-
17
18 415/2005'�+
10
5.0
18
18
19 7/5/2005
2= 10
5.0
19
4
19
20
<'
20
20
21;
21
21
22
¢,
22
22
23
23
r •:
23
24
A,
24
[p
24
25
t
25
-
25
31
27
27
27
28
28'
28
29'
29
29
30
30
30
31
':
31
31
32
�
32 ;
,'�
32
33-
,;
33
33
34
F"
34
34
35
•
35
35
36
; `
36
-`-
36
37 '.
37
37
38
38
38
39
39'
39
40
40
i
40
41
41
t'
41
42
°'
42
42
43
43
43
44
44
44
45
45
46
46
s 1'
46 ,,
46
47
47
47
48
i48
48
49,
49
49
50
50
50
51
51
51
52
52
52
53
53
pp
53
54
54
d d
54
55
55
3l
55
56
d
56
56
57
57
57
58
58
58
59
59 •
59
60
60
60
61
61
61
62
62
62
63,
°
63
63
64
64
64
65
;
65
-
65
66
6
66
67
67
67
68
68
68
69
69
69
70
70
70
71
71
71
72
72
72
7373
73
74
�'
74
74
75
75pj'
75
76
i
76
I
76
77
77
}
e
77
78,
78
78
79
79
79
80
-'�
80
80
81
r
81
d
81
4979_rpa.xls, data
- 4 - 12/14/2005

_y
O
c
d
r
IL
com1 cmmrn .rn mN t
n 1 N N n n n (O m t to m
f� o ' N �
N Nm m M M
O O O O O O O O O O O O O ,
0 0
N 0 0 ........ 0 0 0 0 0 0 0 0
y N N N N N N N N N N N
,a
v n �44izz
p n o o
iz � v l� n
N m t N m n m OI O N m 1 N m n m 0 0 N m 1 N m n m Q O N m 1 N m n m O, O N m t N m n m W ON M 1 N n m O, O N M 1 N tp n m m 0 N m t N m n m m 0
- �-+- NNNNNNNNNNMMMMMmmmMM1 V 1t1111t1NN f0 NNm NN NNNt0Nmc0 t0mmm(pmn f�nn n nn n nnmOD
mmoo oto
N N m O c6
Ci m N t t N
. r O
II U
j a
V d
7� c li> d
y a ami
JtOMtmtc0 N m N mt m O M n m C, nt 1m m 00 1nN.-OM1N"It NNOm tOm 0O, n rn mtrn 7nnV t N N n m t OI Ntm C1 M Nr n 0 N m Nm
N c2 N T ,N-- N ; �� C2 7 N V� Oi N N r c0 a m T r c0 � Oi tcj O O C] O NI tD I� n N OI 00 c7 Qi T ' 00 OD a n m T I� m m cV m W O O m � cD N C] f� tD c7 n V� Oi t0 � Ih O r 1� IO r (V m 1
.- .- .- N N m N t N N• -
J
p
m
t O, M t f t tD N m N c0 t fp m M n m O .- n t It m m .- O r 1 n N .-- n M 1 N 1 N N 1 m n M M O n m m t M n n t t N m n m t O, N 1 m O M N n m N m N m
N N m N Off. N N N' IN 6 w M c i Oi — c6 c6 t 6 T f� N m m Qi cV O O m t0 N m n M I� V N Qi t0 V 1� O' n. n [V M 1�
N N N N N N N N N N N N N N N N N N M m m m m M M M M m m m M M M M M M m M m M M m t t t t t t t t t t t t t t t t t t t t N N N..•N N N N N N N N N N
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O O
QNaNianhNNalN CNNvN aN nNoNoNom c�N nmN `N- uoN��N rnN �NcmN CN �N vN aNoaN mN �N N N N N N N N N N N N N �N N TN N N N N N N N N Nt vN NN nN�N mN N oN rNO nON nONrnnON o,nvm,noNmn n mN NO aNO wON �ON iONn N?O ON".n�
zi ZQ m v Nm o - ac, cvON rnON NrOn�
`ONn CON ONN
nON�NoO,
r N M 1 N f0 n m T O r N M 1 N c0 n m
�-- �- � � � �
O O O O O O O
O u) O O N
O
II U
o
IL
� p c %xx 0.
y V d > > N @
¢ U c
J o 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
N
J
O
m
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
m
N N N N N N N N M m m m 1 1 1 1 N
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
O O O O O O O O O O O O O O O O O
m N N N N N N N N N\ N N N N N N N

01
N
Mn
J
Q
Z
Q
J
Q
Z
W
O
M
W
J
m
Q
Z
0
co)
Q
ui
m
cnD MO � M O V V
ci
o N o
II U
oma
U N
LL
roc >a`
N CA f0 m Q! N : m a M (Ll
�NNv�nvn V NCO �TMNN
J
O
m
N N 7 v,
o N r- v v N rn a n ry��
N 2 N N—
n O m ON N Nm. aN NN NN NN MN ON OM m7 NM MM M am NM m0M M n MM mT O N M V'N I� m OI O N M V N w n m m O N M V N M n M O O N M V N N n M 0 0
r r .- +- M a a a a V V m0 V t N N N N N N N N N N N iD n n n n m
tp N a M O M .-
O OOD V N M
m 0 o cV
11 U
Z5ma
C
�O
N
I
cnD MO � M O V V
ci
o N o
II U
oma
U N
LL
roc >a`
N CA f0 m Q! N : m a M (Ll
�NNv�nvn V NCO �TMNN
J
O
m
N N 7 v,
o N r- v v N rn a n ry��
N 2 N N—
n O m ON N Nm. aN NN NN NN MN ON OM m7 NM MM M am NM m0M M n MM mT O N M V'N I� m OI O N M V N w n m m O N M V N M n M O O N M V N N n M 0 0
r r .- +- M a a a a V V m0 V t N N N N N N N N N N N iD n n n n m
tp N a M O M .-
O OOD V N M
m 0 o cV
11 U
Z5ma
U N
�O
li>a`
c
J O N N V M M n n N N M
N t2 ;E N N O N O N
II
J
O
m

�, r

NO DATA
NO DATA
NO DATA
0
A
m
A
REASONABLE POTENTIAL ANALYSIS
-i-
as as,_
12/1412005
_. Data
nL=1 aL __
,
2 \ 2
* _
mo DATA
m
.
_.
mo A
3
C.V.
NO DATA
!:>
: \n
0
/\
° .
. _ Factor
N/A
7
_.«_
a
,
:.;Q
z Max. m,G
_
1
^ »
\
\
13
#
3
.
s
/
j
\ \
.
20
S
\
/
,
m
2
.
"
2
..
j
{
#
� 7
m
$
\
)
«
,q .
/
»
\
..
.
40
{
a
#
d
45
_
. m
«
y.
+
w,..
e
Q,
50
m
S
o.
.
5
\
m
t
e
. .
2
60
6
\
\
\
65
m
d .
/
e
.
70
2
.
a73
-x
/'
s
s
\
/
/
«
q
-i-
as as,_
12/1412005

Duke
IPower®
n I I
OCT 3 1 2005
October 27, 2005
Ms. LeToya Fields
North Carolina Department of Environment and Natural Resources
Division of Water Quality
1617 Mail Service Center
Raleigh, North Carolina 27699-1617
Subject: Allen Steam Station
Comments on Draft
NPDES Permit No. NC0004979
Dear Ms. Fields:
PROCUREMENT, CONSTRUCTION AND EH&S
Duke Power
526 South Church St.
Charlotte, NC 28202
Mailing Address:
EC13K / P. 0. Box 1006
Charlotte, NC 28201
With reference to the draft NPDES permit Duke Energy Corporation offers the following comments:
In -Stream Wastewater Concentration (IWC) Determination
Mountain Island Hydro is the dam located upstream of Allen Steam Station. Mountain Island Hydro
ensures that a minimum daily average release of 314 cfs (202.8 mgd) occurs. This is a requirement of
current FERC Hydro Operating License Project No. 2232. Using the minimum daily average release
value of 314 cfs and a discharge from outfall 002 of 19 mgd, the IWC equals 8.6 %.
Mean Annual Flow
In review of the operation records from 1929 to the end of 2003 for Mountain Island Hydro the mean
annual flow is calculated to be 2,470 cfs.
Reauested NPDES Permit Revisions
Using the above release rate of 314 cfs, the selenium and Whole Effluent Toxicity (WET) limits for
outfall 002 are requested to be revised. It is requested that the selenium limit be revised to 58 ppb weekly
average. The WET limit is requested to be revised to 9 %. -
With reference to 15A NCAC 02B.0206 (3) (B), based on the mean annual flow of 2,470 cfs, it is
requested that the arsenic limit be removed for outfall 002.
Duke Energy appreciates the opportunity to review and comment on the subject NPDES permit. We are
more than willing to meet with you at your earliest convenience to discuss any of the above. Please
contact me at 704 382-4669 if you have any questions or comments.
Sincerely,
W r
Robert Wylie, Engineer
Environmental Support
www.dukepower.com

r

Re: Thanks for the info
Subject: Re: Thanks for the info
From: Robert R Wylie <[e-mail]>
Date: Tue, 17 Jan 2006 09:58:36 -0500
To: Toya Fields <[e-mail]>
Thanks Toya. Just let me know if you need additional information or have any questions. Duke Energy /
Plant Allen is willing to have the minimum daily average release of 314 cfs as a requirement in the NPDES
permit if that helps matters.
1 of 1 1118/2006 1:59 PN

MOUNTAIN ISLAND HYDRO
Subject: MOUNTAIN ISLAND HYDRO
From: Robert R Wylie <[e-mail]>
Date: Fri, 6 Jan 2006 13:53:44 -0500
To: [e-mail]
Toya,
Today I met with Ed Bruce who is one of the Duke Power permitting representatives for the hydro
relicensing project. The following is in response to your recent questions based on my meeting with Ed
and also includes some facts from previous correspondence.
Mountain Island Hydro releases every day at least a minimum average of 314 cfs (202.8 mgd). So this is
a guaranteed flow every day of the year. The average daily flowrate is substantially higher. A mean
annual daily flowrate has been calculated to be 2,470 cfs.,
The FERC license does not specifically define "daily average". Therefore, it is Duke's interpretation that a
daily average is with respect to a calendar day..
There is a direct correlation between flow through the turbine and megawatts generated. Therefore, the
flow is calculated based on the megawatts that are generated. 1 MW equals 177-cfs. To reach a daily
average flowrate of 314 cfs Mountain Island Hydro is required to generate 31.7 MW -Hours plus 80 cfs for
the continuous leakage rate. MW/flow recordings occur each hour. At noon each day if the minimum 314
cfs has not been already achieved an*alarm will appear in the "Hydro Central" control room and stay lit until
the required daily 31.7 MW is achieved.
Some names of the DENR representatives involved in the hydro relicensing project were mentioned to me.
These employees are 'Dan Rayno, Tom Franson, Steve Reed and Jim Mead. It may be of'some benefit to
touch base with them.
Duke is committed to releasing a minimum daily"average of 314 cfs at the Mountain Island Hydro Station.
If a check and balance is needed such as providing the daily releases on each monthly DMR Duke is
willing to do so.
Please let me know if youneed further clarification or information.
Thanks,
Robert Wylie
Environment, Health and Safety
Office Phone Number 704 382-4669
Cell Phone Number 704 562-8258
Fax Number 704 382-6240
Mail Code: EC13K
1 of 1 1/18/2006 1:58 PU

FW: MOUNTAIN ISLAND HYDRO RELEASES
Subject: Fw: MOUNTAIN ISLAND HYDRO RELEASES
From: Robert R Wylie <[e-mail]>
Date: Thu, 5 Jan 2006 17:09:22 -0500
To: [e-mail]
Toya,
I have corrected my last comment. I was just informed by Hydro that we "certify" that we have met the
requirements,
Robert Wylie
Environment, Health and Safety
Office Phone Number 704 382-4669
Cell Phone Number 704 562-8258
Fax Number 704 382-6240
Mail Code: EC13K
----- Forwarded by Robert R Wylie/Gen/DukePower on 01/05/2006 05:07 PM -----
Robert R Wylie/Gen/DukePower To Toya Fields <[e-mail]>
01/05/2006 12:42 PM cc
Subject Re: MOUNTAIN ISLAND HYDRO RELEASESLink
Toya,
The following is in response to your questions. If you need a lot more detail in the equipment
used and actual process please let me know.
Thanks,
Robert
As far as you know, is there any place that FERC specifically defines the calculation of this
value?
FERC license No. 2232 states that a minimum daily average release of 314 cfs is required.
Also, how is release compliance tracked by Duke?
On a daily basis Duke ensures that the minimum flows are met based on the amount of MW generated.
There is a direct correlation for a hydro station between flow and generation. So the central
Duke Power control room tracks to ensure that the minimum MW is generated each day.
How is it tracked by FERC?
An annual compliance report is submitted to FERC that certifies the FERC requirements have been
met.
1 of 3 1/11/2006 1:54 PM

Fw: MOUNTAIN ISLAND HYDRO RELEASES
Toya Fields <[e-mail]>
01/05/2006 09:33 AM
Thanks Robert,
To Robert R Wylie <[e-mail]>
cc
Subject Re: MOUNTAIN ISLAND HYDRO RELEASES
As far as you know, is there any placelthat FERC specifically defines
the calculation of this value? Also, how is release compliance tracked
by Duke? How is it tracked by FERC?
Thank for your help with answering all the questions. George Everett
from Duke has been in contact with the Director and he wants to meet
internally to discuss this issue. These are some of the questions that
have come up.
Toya
Robert R Wylie wrote:
> Toya,
> The FERC license requirement is a cal(
> requirement.
> Robert Wylie
> Environment, Health and Safety
> Office Phone Number 704 382-4669
> Cell Phone Number 704 562-8258
> Fax Number 704 382-6240
> Mail Code: EC13K
> *Toya Fields <[e-mail]>�
> 01/04/2006 01:31 PM
> To
> Robert R Wylie <rrwy_
> cc
> Subject
> Re: MOUNTAIN ISLAND F
> Thanks Robert,
> I did a quick scan and in September t)
> the flow stays at 80cfs. One beginnii
> 9/22.
2 of 3
day minimum average flow
[e-mail]>
RELEASES
e are two 25 -hour periods where
on 9/15 and another beginning on
1/11/2006 1:54 PM

Fw: MOUNTAIN ISLAND HYDRO RELEASES
> -ALert R Wylie wrote:
> > Toya,
> > The attachment includes the all the hourly release flow (including
> > corrected values) for Mountain Island Hydro during the drought of
> > 2002. These are for the months of July through Sept. Upon receipt of
> > June's data I forward it to you.
> > Please call me if you have any questions or need additional information.
> > Thanks,
> > Robert Wylie
> > Environment, Health and Safety
> > Office Phone Number 704 382-4669
> > Cell Phone Number 704 562-8258
> > Fax Number 704 382-6240
> > Mail Code: EC13K
> Toya Fields - [e-mail]
> Environmental Engineer I
> Western NPDES Program
> Division of Water Quality
> Tel: [phone] x 551
> Fax: [phone]
> [attachment "toya.fields.vcf" deleted by Robert R Wylie/Gen/DukePower]
Toya Fields - [e-mail]
Environmental Engineer I
Western NPDES Program
Division of Water Quality
Tel: [phone] x 551
Fax: [phone]
[attachment "toya.fields.vcf" deleted by Robert R Wylie/Gen/DukePower]
3 of 3 1/11/2006 1:54 PM

Rd: Duke Power- minimum instantaneous release
Subject: Re: Duke Power- minimum instantaneous release
From: Matt Matthews <[e-mail]>
Date: Wed, 04 Jan 2006 18:23:27 -0500
To: Toya Fields <[e-mail]>
Toya,
I have some questions and some comments about this. I'll follow up with a phone call tomorrow.
1. I am assuming we used 80 cfs to calculate limits previously. Is this correct?
2. I'm curious about the nature of the scrubber waste stream. Can the facility provide characterization
data or is there a similar waste stream at another Duke plant?
Comments:
1. The October 2001 failure was based on seven-day reproduction suppression (34% reduction from
control), so this, on its face, does not make an argument for acute toxicity concerns. The October 2003
failure was based on 58% mortality over 48 hours. To me, this most recent failure puts us on solid
ground regarding "acute toxicity concerns" using the current 16% limit, much less 24%. Note that the
toxicity occurred over 48 hours and we can document they've maintained 80 cfs for 96 hours in the past.
2. Another to look at the issue of acute toxicity has to do with mixing zones. Their current chronic WET
limit assumes instantaneous mixing across the entire stream seqment to get to that 16% concentration
value. Depending on whether the outfall has a diffuser, we may not be adequately protecting the stream
in the immediate area of the outfall. We may want to consider asking them to model their outfall and
assign a chronic limit based on the concentration of the effluent at the edge of the chronic mixing zone,
or possibly assign an acute limit as well, based on the effluent concentration at the edge of the acute
mixing zone.
3. Should we back away from 80 cfs based on the "downstream attenuation" argument, we should
require the facility to conduct a flow study to generate an appropriate number.
I'll talk to you tomorrow,
Matt
Toya Fields wrote:
Hi Matt,
Duke Power has requested that we change the 7Q10 flow estimate we're using at their Allen Plant.
We are using the minimum instantaneous flow release at the Mountain Island Dam as defined in the
FERC license (80 cfs). They feel that we should be using the minimum daily average release, also
defined in the license (315 cfs). They argue that 7Q10 is defined as a 7 -day average flow and
therefore minimum average daily flows are more appropriate. There is a rule regarding this,
however we have interpreted it to support our flow value and they have interpreted it to support
theirs. The rule is 02B.0206(b). We met with the facility and asked them to provide us with actual
1 of 2 1/11/2006 1:58 P1Vl

Re: Duke Power- minimum instantaneous release
releases during a drought period (Jun
that the dam maintains the minimum
increases the release (above 2000 cfs
of this data electronically, if you'd lik
periods during this time frame where
consecutive 4 -day period. During thi
to around 6000 cfs which increases tl
Duke argues that based on attenuatii
that are released from the damn. TI
7Q10 might be, however during the
(under 300 cfs). We noted that this
We tend to feel that in order to pr(
the lower flow. The facility has a
additional metals limits once they
discharge.
-August 2002). Based on the information they sent it appears
nstantaneous flow approximately 19-21 hours a day, and then
for several hours to meet the daily requirement. I have a copy
to see it. However it appears that there are at least two
he minimum average daily release was not met. One was a
time the release stayed at 80 cfs, constantly. It then went up
daily average (depending on the period of calculation).
11 miles downstream, you do not see the high and low flows
did not provide us with a calculated estimate of what a "true"
seting their modeler guesstimated a flow of "two -something"
lue is still below the average daily minimum requirement.
against acute toxicity concerns in the stream, we need to use
aic WET requirement and a selenium limit. They may have
y for a permit modification to add scrubber wastewater to the
It looks like Alan would like to speak1with Susan and myself about this matter. We wanted to get
your thoughts. I can give you a call a little later but wanted to give you a quick email overview.
Thanks,
Toya
Matt Matthews
NC DENR/Division of Water Quality
Aquatic Toxicology Unit
1621 Mail Service Center
Raleigh, North Carolina 27699-162
v-[phone], ext. 256
f-[phone]
[e-mail]
http://h2o.enr.state.nc.us/esb/
2 of 2 1/11/2006 1:58 PM

Re: MOUNTAIN ISLAND HYDRO DATA
R
Subject: Re: MOUNTAIN ISLAND HYDRO DATA
From: Robert R Wylie <[e-mail]>
Date: Thu, 22 Dec 2005 13:35:11 -0500
To: Toya Fields <[e-mail]>
Toya,
Your initial definition is accurate.. I will need to go back and check on the days of concern.
Everyday there should be at least a daily minimum average of 314 cfs.
Robert Wylie
Environment, Health and Safety
Office Phone Number 704 382-4669
Cell Phone Number 704 562-8258
Fax Number 704 382-6240
Mail Code: EC13K
-----Toya Fields <[e-mail]> wrote: -----
To: Robert R Wylie <[e-mail]>
From: Toya Fields <[e-mail]>
Date: 12/22/2005 01:24PM
Subject: Re: MOUNTAIN ISLAND HYDRO DATA
Thanks Robert,
One question: how is "minimum average daily release" defined? I had
assumed that it was a 24 hour average but from looking at the data it
appears that it might actually be an average over a period of several
days. There are several periods of time where the 80 cfs is released
for more than 24 consecutive hours, and in one case it remained at that
value for over 4 days.
Robert R Wylie wrote:
> Toya,
> Attached is the spreadsheet for the hourly release rate from Mountain
> Island Hydro during the summer drought of 2002. Please let me know if
> you need any additional information.
> Thanks,
> Robert Wylie
> Environment, Health and Safety
> Office Phone Number 704 382-4669
> Cell Phone Number 704 562-8258
> Fax Number 704 382-6240
> Mail Code: EC13K
Toya Fields - [e-mail]
Environmental Engineer I
Western NPDES Program
Division of Water Quality
Tel: [phone] x 551
Fax: [phone]
1 of 2 1/18/2006 1:58 PN

Re: MOUNTAIN ISLAND HYDRO DATA
[attachment "toya.fields.vcf' removed by Robert R Wylie/Gen/DukePower]
2 of 2 1 1/18/2006 1:58 PN

Re: draft permit for Allen Steam
Subject: Re: draft permit for Allen Steam
From: [e-mail]
Date: Mon, 31 Oct 2005 15:32:29 -0500
To: Toya Fields <[e-mail]>
Sounds good. Thanks for revising the FS.
Karrie-Jo Robinson -Shell, P.E.
Toya Fields
<toya.fields@ncm
ail.net>
10/31/2005 03:27
PM
Hi Karrie,
To
Karrie-Jo Shell/R4/USEPA/US@EPA
cc
Subject
Re: draft permit for Allen Steam
The following justification was included in the previous permit file,
when the limit was first established. I will add it to the fact sheet.
Originally the explanation was sent from Robert Wylie (Duke
representative) to you and Natalie Sierra (former permit writer).
"The limit of 50 mg/L TSS for the coal yard sump is form 40 CFR 423,
however it applies to coal pile -runoff during a rainstorm event. The
layout for the coal yard sump is such that an overflow would most likely
be low volume wastewater instead of coal pile run off. Chemical metal
cleanings do not go to this sump. Therefore it was agreed that the
limits for this sump should be O&G 20 mg/L daily max and 15 mg/L monthly
average and TSS- 100 g/L daily max and 30 mg/L monthly average..."
Let me know if this is sufficient.
Toya
[e-mail] wrote:
LaToya,
The daily max TSS limit for outfall 002A should be 50.0 mg/l, unless
the
basin is constructed & operated to retain the 10Y24H storm event. See
40 CFR 423.12(b)(9) & (10). I could not tell from the fact sheet if
this was the case. Please revise the DM limit on page 5 of the permit
to 50 mg/l or include a discussion in the fact sheet about the volume
of
Ithe coal pile run-off basin.
1 of 2 11/1/2005 9:50 AM

Re: draft permit for Allen Steam
I ,.!S
Karrie-Jo Robinson -Shell, P.E.
Toya Fields - [e-mail]
Environmental Engineer I
Western NPDES Program
Division of Water Quality
Tel: [phone] x 551
Fax: [phone]
(See attached file: toya.fields.vcf)
Content -Type: application/octet-stream i
toya.fields.vcf i
Content -Encoding: base64
2 of 2 11/1/2005 9:50 AM

4. 1