NC0004987_Review of Draft Permit_20090324

2i
NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins
Governor Director
March 24, 2009
MEMORANDUM
To: Britt Setzer
NC DENR / DEH / Public Water Supply Section Regional Engineer
Mooresville Re 'onal Office
From: Jackie Nowell. a
NPDES Western Program
Subject: Review of Draft Permit NC0004987
Duke Energy — Marshall Steam Station
Catawba County
Dee Freeman
Secretary
Public Wer�ar��i J.
Please indicate below your agency's position or viewpoint on the draft permit and return this form by May 1, 2009. If
you have any questions on the draft permit, please contact me at 919-807-6386 or e-mail to [e-mail].
RRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRRR
7RESPO SE: (Check one)
Concur with the issuance of this permit provided the facility is operated and maintained properly, the stated effluent
limits are met prior to discharge, and the discharge does not contravene the designated water quality standards.
F-1
Concurs with issuance of the above permit, provided the following conditions are met:
F-1
Opposes the issuance of the above permit, based on reasons stated below, or attached:
Signed / . Date: 3 12 &1e
1617 Mail Service Center, Raleigh, North Carolina 27699-1617
Location: 512 N. Salisbury St. Raleigh, North Carolina 27604 One
Phone: [phone] \ FAX: [phone] \ Customer Service: 1-877-623-6748 NorthCarolina
Internet: www.ncwaterquality.org 'J����u6 y,� l//�
An Equal Opportunity \ Affirmative Action Emi/ployer ►�

FW: re NC0004987. Marshall Steam Plant
Subject: FW: re NC0004987, Marshall Steam Plant
From: [e-mail]
Date: Wed, 1 Apr 2009 08:29:06 -0400
To: [e-mail]
EPA has no comments on this draft permit. I do request that a summary
of any information submitted by the facility regarding compliance
schedule milestones or how the permit is changed to reflect that
information be submitted.
I mislabeled the previous email for Lee Steam.
1 of 1 4/1/2009 2:55 PM

RE: MARSHALL NPDES PERMIT
Subject: RE: MARSHALL NPDES PERMIT
From: "Wylie, Robert R' <[e-mail]>
Date: Fri, 20 Mar 2009 11:43:08 -0400
To: Jackie Nowell <[e-mail]>
Jackie,
Thanks for sending this to me for a review. Duke Energy will do a thorough review
during the comment time period and provide any further comments accordingly. In the
interim comments for you to consider are as follows:
COVER PAGE
Change WS' to IV.
- BOD5 is not arameter that r quires monitoring.
DOCUMENTS
- Where 4DuEnergy Corpo tion is listed please change to Duke Energy Carolinas, LLC
- Refeeo Outfall 002 a and b. The permit lists the "a and b" in capital
letters.
PAGE 5 f 13
E urinate footnote 3 since this was put in the last permit to capture when the FGD
was water reatment system began operation. A discharge from outfall 004 is almost
continuou Adjust the footnote numbers accordingly.
PAGE 9 of 1/3
E imin to the last sentence associated with the DMRs being submitted after the
di harg commences. The discharge began in December 2006.
- Duke/also requested that Total Suspended Solids be eliminated in the modification
requeW. Has this been considered? If so please address in ns -,mit
PAGE lI of 13
- Please co &irm. the referenced DWQ form that is listed in the middle of the page.
J �
FACT SHE
2 o fact sheet delete "influent" monitoring for outfall 004.
Pagb 4 of fact sheet delete new for the sanitary treatment system.
RPA
- Lookout Shoals is the hydro station upstream of Marshall. The current commitment
is for a minimum release of 60 cfs. In 2010 it is expected that the new FERC license
will be issued and in the "Comprehensive Relicensing Agreement" Duke Energy Carolinas,
LLC is in agreement to release on a continuous basis 80 cfs. This is a long term
commitment that will change the RPA and IWC.
There are several other comments primarily in the fact sheet that we need to discuss
or I can mark up and send to you. Just let me know how you want to handle. For now
the above are some of the areas that jumped out that I wanted you to be aware of. I
am in my office today and all day on Monday and Tuesday if you would like to discuss.
Thanks,
1 of 3 3/20/2009 12:51 Ph

3/17/2009
jmn
2008 Qw
Jan -08
8.294
Feb -08
7.844
Mar -08
8.734
Apr -08
9.204
May -08
9.204
Jun -08
7.004
Jul -08
7.844
Aug -08
9.204
Sep -08
10.184
AVERAGE
8.613
3/17/2009
jmn
8.046296 Aug -07
Marshall Steam Station
Sep -07
7.844
Oct -07
Average
Yearly Wastef lows (MGD)
8.294
Dec -07
7.844
Outfall
002
Feb -08
7.844
Mar -08
8.734
Apr -08
9.204
Date
Qw (mgd)
Jun -08
7.004
Jul -08
7.844
Jan -06
7.954
Sep-08
10.184
Average
7.99
Feb -06
7.744
Mar -06
5.724
2007 Qw
2006 Qw
Apr -06
6.794
Jan -07
14.054
Jan -06
7.954
May -06
8.064
Feb -07
7.744
Feb -06
7.744
Jun -06
5.254
Mar -07
8.624
Mar -06
5.724
Jul -06
8.414
Apr -07
7.844
Apr -06
6.794
Aug -06
7.324
May -07
7.844
May -06
8.064
Sep -06
7.754
Jun -07
7.96
Jun -06
5.254
Oct -06
5.824
Jul -07
10.174
Jul -06
8.414
Nov -06
6.684
Aug -07
9.204
Aug -06
7.324
Dec -06
7.314
Sep -07
7.844
Sep -06
7.754
Jan -07
14.054
Oct -07'
4.034
Oct -06
5.824
Feb -07
7.744
Nov -07
8.294
Nov -06
6.684
Mar -07
8.624
Dec -07
7.844
Dec -06
7.314
Apr -07
7.844
AVERAGE
8.455
AVERAGE
7.071
May -07
7.844
Jun -07
7.96
Jul -07
10.174
8.046296 Aug -07
9.204
Sep -07
7.844
Oct -07
4.034
Nov -07
8.294
Dec -07
7.844
Jan -08
8.294
Feb -08
7.844
Mar -08
8.734
Apr -08
9.204
May -08
9.204
Jun -08
7.004
Jul -08
7.844
Aug -08
9.204-
.204Sep-08
Sep-08
10.184
Average
7.99

DENR/DWQ
FACT SHEET FOR NPDES PERMIT DEVELOPMENT
NPDES No. NC0004987
Facility Information
Applicant/Facility Name:
Duke Energy Carolinas, LLC — Marshall Steam Station
Applicant Address:
'163.3ftgge s Fga, oad Innt,0rsv+lle-+; Na— 2v r(/Jct y� GG!
Facili Address:
8320 E. NC Highway 150, Terrell, NC 28682
Permitted Flow
Not Limited
e of Waste:
100% Industrial
Facility/Permit Status:
Existing/Modification
County:
Catawba
BACKGROUND
Duke Energy Carolinas LLC has requested a permit modification seeking a reduction in frequency or the
elimination of monitoring for effluent parameters from outfall 002 (ash basin discharge) and internal outfall
004 (Flue Gas Desulfurization treatment system discharge.). The request was as follows:
Outfall 002
Reduce from weekly monitoring to monthly monitoring. Chloride and Selenium
Elimination of weekly monitoring: Arsenic, Cadmium, Chromium, Mercury, Nickel, Silver and Zinc.
Zaw�
Outfall. 004
Reduce from weekly monitoring to monthly monitoring: Chloride and Selenium
Elimination of weekly monitoringA
. rsenic, Cadmium, Chromium, Mercury, Nickel, Silver, TSS and
Zinc. /, 7
SUMMARY OF FACILITY AND WASTELOAD ALLOCATION.
Duke Energy operates Marshall Steam Station in Catawba County. The Station operates five outfalls. These
outfalls are 001, 002, 002A, 002f and 003. The permitted outfalls are summarized below:
• Outfall 001 —Condenser Cooling Water (CCW) Units 1 — 4:
d� The CCW system is a once- through, non -contact cooling water system, which condenses steam from
the -eandem-ers-and other selected heat exchangers. When the station is operating at full power, it has a
design capacity to pump 1463 MGD (1.016 MGPM) of cooling water through the network of tubes that
runs through the condenser and selected heat exchangers. The raw cooling water is returned to the lake.
No biocides or other chemicals are used in the condenser cooling water.
Units 1 and 2 operate two CCW pumps each while units 3 and 4 operate three pumps. The operational
schedule for these pumps is dependent on the intake water temperature and on the unit loads.
Depending on the electrical demand, pumps are operated to maximize station efficiency and to assure
balanced and indigenous populations are maintained in Lake Norman. Each unit is on an independent
system to avoid a system trip that would suddenly reduce the discharge flow at outfall 001. This practice
leads to a higher reliability factor for the units and protection of aquatic life taking refuge in the discharge
Marshall Steam Station Fact Sheet
NPDES Modification
Page 1
Miscellaneous
Receiving Stream:
Lake Norman
Regional Office:
Mooresville
Stream Classification:
WS -IV & B CA
USGS To o Quad:
303(d) Listed?:
No
Permit Writer:
Jacquelyn M. Nowell
Subbasin:
03-08-32
Date:
March 6,2009
Drainage Area (mi2):
NA'
_
`
Summer 7Q 10 (cfs) Release (60 cfs)"
Winter 7Q10 (cfs): NA
Average Flow (cfs) : NA
IWC (%): See Below
BACKGROUND
Duke Energy Carolinas LLC has requested a permit modification seeking a reduction in frequency or the
elimination of monitoring for effluent parameters from outfall 002 (ash basin discharge) and internal outfall
004 (Flue Gas Desulfurization treatment system discharge.). The request was as follows:
Outfall 002
Reduce from weekly monitoring to monthly monitoring. Chloride and Selenium
Elimination of weekly monitoring: Arsenic, Cadmium, Chromium, Mercury, Nickel, Silver and Zinc.
Zaw�
Outfall. 004
Reduce from weekly monitoring to monthly monitoring: Chloride and Selenium
Elimination of weekly monitoringA
. rsenic, Cadmium, Chromium, Mercury, Nickel, Silver, TSS and
Zinc. /, 7
SUMMARY OF FACILITY AND WASTELOAD ALLOCATION.
Duke Energy operates Marshall Steam Station in Catawba County. The Station operates five outfalls. These
outfalls are 001, 002, 002A, 002f and 003. The permitted outfalls are summarized below:
• Outfall 001 —Condenser Cooling Water (CCW) Units 1 — 4:
d� The CCW system is a once- through, non -contact cooling water system, which condenses steam from
the -eandem-ers-and other selected heat exchangers. When the station is operating at full power, it has a
design capacity to pump 1463 MGD (1.016 MGPM) of cooling water through the network of tubes that
runs through the condenser and selected heat exchangers. The raw cooling water is returned to the lake.
No biocides or other chemicals are used in the condenser cooling water.
Units 1 and 2 operate two CCW pumps each while units 3 and 4 operate three pumps. The operational
schedule for these pumps is dependent on the intake water temperature and on the unit loads.
Depending on the electrical demand, pumps are operated to maximize station efficiency and to assure
balanced and indigenous populations are maintained in Lake Norman. Each unit is on an independent
system to avoid a system trip that would suddenly reduce the discharge flow at outfall 001. This practice
leads to a higher reliability factor for the units and protection of aquatic life taking refuge in the discharge
Marshall Steam Station Fact Sheet
NPDES Modification
Page 1

q9 l
canal during cold weather. Flow recorded on the monthly Discharge Monitoring Reports is based on
CCW pump runtimes.
• Outfall 002 — Ash Basin:
The station ash basin accommodates flows from two yard -drain sumps, an ash removal system, low
volume wastes and non -point source stormwater. Low volume waste sources include, but are not limited
to: wastewater from wet scrubber air pollution control systems, ion exchange water treatment system,
water treatment evaporator blowdown, laboratory and'sampling streams, boiler blowdown, floor drains,
and recirculating house service water systems. Total average influent fromthese sources combined is
approximatelykmGD. At times, due to unit loads, rainfall, evaporation, and seepage of ash basin
ponds, the effluent flow may vary from the influent flow.
• Outfall 004 (internal outfall) — FGD system discharge into Ash Basin:
In association with Clean Smokestacks legislation, Duke Energy. has. installed a flue -gas desulfurization
(FGD) wet scrubber. This scrubber generates a wastewater needing treatment prior to discharge. An
internal outfall (004) has been established for the effluent from the FGD treatment system. Weekly -
effluent monitoring has been established at outfall 004 for flow, arsenic, cadmium, chromium, chloride,
mercury, nickel, selenium, silver, suspended solids, and zinc.,TAts inr�fluenLmonitQ= _all-ows-the
f�c�_Ls_sse- ss't e �e tiveness ofjitts_FGD treat_+ve�nt�stem.
Internal outfall 004 discharges to the ash settling basin
is currently permitted as outfall 002. o o ' "t-�.
Duke Energy has been working with faculty from Clemson University to identify FGD wastewater treatment
options. Pilot scale constructed wetlands have provided positive results. Construction of a clarifier,
equalization basin, and constructed wetland to treat the FGD wastewater was completed in October 2006.
The yard -drain sumps are concrete structures having four level controlled pumps each that direct wastewater
from the powerhouse area to the ash basin. These pumps are operated on a rotating basis. Usually two
pumps are set so that one pump is primary and the other is backup. After a selected period the controls are
changed so that different pumps are utilized. The yard -drain sumps collect wastewater from many sources,
such as the filtered water system, turbine and boiler room sumps, miscellaneous equipment cooling water,
foundation drainage, low volume wastes, and tunnel dewatering. The yard -drain sumps also collect some
stormwater runoff from the coal pile. (coal pile runoff), rail access, and powerhouse roofs and pavement.
Groundwater from a foundation drainage system under the track hopper is also intermittently discharged to
the yard -drain sumps. The combined average flow from all sources tied to the yard -drain sumps is
approximately ]MGD, which is pumped to the ash basin for physical and biological treatment.
/ 0.' 3-
The turbine room sumps collect approximately MGD of wastewater. This wastewater comes from non -
contact cooling water (from Units 1 & 2 boiler feed -pump turbine lube oil coolers) and floor drains. Floor
drains contain boiler blowdown, leakage from seals, equipment cooling water, condensate from the feed -
water system, low volume wastewater, boiler room sump overflow, emergency fire fighting water, general
mechanical maintenance activities, miscellaneous plant wastes and area wash -down water.
The average flow pumped from the boiler room sumps directly to the ash basin is approximately 1.3 MGD.
The sources of input to the boiler room sumps includes the following:
Water Treatment System — the station make-up water treatment system consists of a clarifier,
three gravity filters, two sets of activated carbon filters, and two ,sets of demineralizers. The
water treatment `wastes consist of floc and sedimentation, filter. backwash, and demineralizer
regeneration wastes. Make-up water is supplied to the boilers to generate steam to turn the
turbines. On occasion a vendor may be used with a mobile water treatment unit to augment the
facility water treatment capacity. Any vendor will use traditional water treatment methods,
chemicals, and disposal methods.
Marshall Steam Station Fact Sheet
NPDES Modification
Page

• Miscellaneous Waste Streams:
• Closed system drainage, cleanings, testing containing corrosion inhibitors AVgo
biocides cleanings (small heat exchangers), dispersant (polycrylamide),
wetting agent (sodium lauryl sulfate), detergent (tri -sodium phosphate), and leak testing
(disodium fluorescing dye);
• Turbine room sump overflow;
• Boiler seal water (trace oil and grease);
• Miscellaneous system leakages (small leaks from pump packings and seals, valve seals, pipe
connections);
• Moisture separators on air compressor precipitators;
• Floor wash water;
• Emergency fire fighting water; .
• Pyrite (ash) removal system overflow;
• Low volume wastewater.
• Chemical makeup tanks and drum rinsate - intermittent rinse water containing small amounts of
aluminum sulfate, sodium hydroxide, hydrazine, and ammonium hydroxide.
• Boiler blowdown — Primarily when units 1 & 2 startup and until water chemistry stabilizers the
blowdown from these boilers is allowed to flash in a blowdown tank. During startup a
significant portion of this blowdown steam is vented to the atmosphere. After water chemistry
has stabilized, blowdown venting is minimal and condensate flow is small. Trace amounts of
hydrazine, ammonia, and silica oxide may be present in the condensate. The combined
condensate flow from blowdown amounts to an average of approximately 0.002 MGD. This
flow is routed to the boiler room sump and then to the ash basin.
• Boiler cleaning — Boilers #1, #2, #3, and #4 at the station are chemically cleaned on an as
needed basis. Tube inspections are performed during outages, which indicate when cleaning
needs scheduling. Boilers #1 and #2 are controlled circulation boilers and boilers #3 and #4
are supercritical boilers. The wastes produced from a boiler cleaning are pumped to the yard
sumps and then to the ash basin.
The ash basin collects stormwater flows from the yard drainage basin, ash removal lines and rainfall runoff
from the basin watershed area. A total of 14-7'acres drain to the yard sumps with an average daily runoff
estimated at 0.03 MGD. The average daily runoff is calculated based on an annual rainfall of 49 inches with
1.0 and 0.5 runoff coefficients applied appropriately. Trace amounts of oil and grease may be present in the
first flush of stormwater.
Once -through, non -contact cooling water is supplied to eight induced draft (ID) fan motor bearings to
remove excess heat. No chemicals are added to the once -through raw lake water. The rate of flow through
the ID fan heat exchangers that discharges to the yard -drain sumps is approximately 0.08 MGD, which is
pumped to the ash basin.
The track hopper sump collects groundwater from a foundation drain system underneath the track hopper.
The flow is usually intermittent; however, the pump capacity is 100 gpm. On a daily basis it is estimated that
the run time is only 500%, which would correspond to a flow of 0.07 MGD to the yard -drain sumps; then to
the ash basin.
In the event that maintenance activities are needed in the intake or discharge tunnels, a dewatering sump is
provided to remove water from the tunnels. Raw water in the tunnels can be pumped to the yard -drain
sumps that ultimately discharge to the ash_ basin.
Bore sonic testing of turbine rotors is infrequent, occurring approximately once every 5 years. Demineralized
water is mixed with a corrosion inhibitor, e.g. Immunol 1228, at a ratio of 100 parts water to 1 part inhibitor.
Marshall Steam Station Fact Sheet
NPDES Modification
Page

The mixture is applied to the turbine rotors. The excess is drained and mixed with low volume wastewater
and discharged to the ash basin via the yard -drain sumps.
The station utilizes electrostatic precipitators as its air pollution control devices. Under normal plant
operations, the dry ash captured in these precipitators is collected in temporary storage silos for subsequent
disposal in a permitted on-site JAdfZor for recycling in off-site ash utilization projects. If, the system that
�Gf l collects the dry fly ash is not operating the fly ash can be sluiced to the ash basin. Bottom ash from the
boilers is usually sluiced with water to a holding cell for recycling activities. Pyrites from the mills are sluiced
�p with water to an ash basin settling cell. Approximately/2 5 MGD of bottom ash and pyrite sluice is pumped
through large steel pipes (ash lines) directly to the ash basin settling cell. Once -through, non -contact cooling
water from the coal pulverizing mill is discharged to the bottom ash hopper and pumped to the ash basin.
The electrostatic precipitators are normally cleaned by mechanically vibrating the wires and rapping the plates
inside the precipitator. Before major precipitator work is performed, they are cleaned by a wash down. The
wash water is pumped to the ash basin from the yard -drain sump.
A sanitary waste treatment system was installed during the term of any earlier NPDES permit, thus
eliminating the package plant near the intake structure of the plant. An aerated basin provides treatment with
a 30 — day retention time and has a total volume of 587,000 gallons. Effluent from the aerated basin is
polished further through additional residence time in the, ash basin. The nneewssystem is designed for 6100
gpd (normal) and 13500 gpd (outage). 1b o
The powerhouse lift station was installed as a central collection point to receive all the sanitary waste from
the station and pump it to the aerated basin. The present lift station serving the vendor facilities and Units 3
and 4 were upgraded.
The sanitary_ system accommodates wastewater flow from the following courses:
• General Plant sanitary wastewater;
• Vendor facilities sanitary wastewater; and
• Laboratory drains (small amounts of laboratory chemicals used to test wastewater effluents and
high purity boiler water).
Non -point sources of st water to the ash basin includes coal pile runoff, a pond area of 82.3 acres and an
up -gradient watershed � of 1097.7 acres. The estimate for stormwater runoff is based on forty-nine inches
of rain per year with a 1.0 and 0.5 runoff coefficient for the pond area and up -gradient watershed,
respectively. The average non -point source stormwater input for the ash basin is estimated at23'MGD.
Zo6
The coal pile covers an area of approximately 33 acres with an estimated stormwater runoff to the ash basin
of 0.06 MGD.
•. Outfall 002 Sump #1 Overflow:
This outfall discharges very infrequent overflows of yard sump number 1. The overflow generally
consists of the same wastewaters discharged by the ash basin. C s l'jCC�i, l e ` ��yi1j�y cf
• Outfall 002— Sump #2 Overflow:
This outfall discharges very infrequent overflows of yard sump number 2. The overflow gener
consists of the same wastewaters discharged by the ash basin.
• Outfall 003 — Unit 4 ID Fan Control House Cooling Water:
Once -through, non -contact cooling water is supplied to the Unit 4 induced draft (ID) fan motor control -
house equipment to remove excess heat. No chemicals are added to the once -through raw lake water.
The flow rate through the control equipment that discharges to Lake Norman is approximately 0.2
MGD.
One of the previous permit requirements was to perform an assessment of balanced and indigenous
populations in Lake Norman. The report stated that "the thermal regimes resulting from the operation of
Marshall Steam Station Fact Sheet
NPDES Modification
Page 4

the MSS (Marshall Steam Station have supported the protection and propagation of a balanced and
indigenous fish community in Lake Norman".
BASIS FOR EFFLUENT LIMITS
• Outfall 001- Condenser Cooling Water (CCW) Units 1 - 4:
Currently, only temperature is limited in this outfall. Summer and winter thermal limits have been
established in support of the 316 temperature variance issued by EPA in May of 1975. The
determination noted that the "th i component of the discharge assures the protection and
propagation of shellfish, fish, and wildlife in and on the receiving body of water." Continued
—�inplEiiientation of the aforementioned thermal variance is supported by the "Assessment of Balanced
Jnnr1V and Indigenous Populations in Lake Norman near Marshall Steam Station." Furthermore, an evaluation
i4�jS ng in
f the
downstream
temperature of Lake Norman suggests that Marshall Steam Station is not appreciably
A free available chlorine limit is currently part of the effluent limitations for this outfall. 40 CFR 423.12 (b)
(6) establishes maximum free available chlorine concentrations for discharges of once -through cooling water.
These maximum values are 0.5, mg/L and 0.2 mg/L daily maximum and monthly average respectively.
Inclusion of these limits is merely a matter of record keeping as the permit does not authorize chlorination of
the once -through cooling water. These limits will be footnoted such that monitoring is only required if the
facility proposes to implement chlorination of its once -through cooling water.
• Outfall 002 - Ash Basin:
The existing permit limits oil & grease, TSS, pH, total copper, and total iron at this outfall. Limits for Cu
and Fe are �or�sstent with federal guidelines Effluent monitoring has been established for flow, total
arsenic, total ca .um, total chromium, chloride, total mercury, total nickel, total selenium, total silver,
and total zinc. /E f r" tlhe greLvijo�i ,list'e11 parameters is-recu�ri ed on/'ly�sh-6n-oulfall-(Y04.)
15 S G1tt t /j�✓` Ime fillF7�lf Jir�t��%. ��G/J�V`�/ ,a� C/iy✓ri�
• Outfalls 00 and 002- Yard -Sump Overflows:
On occasion, the and -sumps at the station experience overflows. These overflows occur rarely, typically
once per year, and can range in time from less than one hour to several hours.. Late in 1998, the Division
developed a permitting strategy for these overflows. Analytical monitoring is required for flow, pH, and
TSS for all overflows lasting longer than an hour. When TSS is reported as greater than 100 mg/L,
monitoring for iron is required. All overflows, regardless of time length, are reported to the DWQ
regional office.
• Outfalls 003 - Non -Contact Cooling Water:
Limitations for this outfall are consistent with non -contact cooling water requirements defined in the
federal guidelines.
TOXICITY TESTING:
Current Requirement: Outfall 002 - Chronic P/F @ 12% using Ceriodaphnia
Recommended Requirement: Outfall 002 - Chronic P/F. @ 12% using Ceriodaphnia
No changes in the toxicity testing requirements are recommended at this time. This facility has passed all
toxicity tests during this permit cycle (4/2005 through 12/2008).
COMPLIANCE SUMMARY:
A review of this facility's effluent data indicates an excellent compliance history with no noted permit limit
violations durin the review period (4/2005 -12/2008).
INSTREAM MONITORING:
None Required
Marshall Steam Station Fact Sheet
NPDES Modification
Page

REASONABLE POTENTIAL ANALYSIS (RPA)
For the major modification request, the Division conducted EPA -recommended analyses to determine the '
reasonable potential for toxicants to be discharged by this facility from outfall 002. The average flow from
outfall 002 for the past three years has been 7.99 MGD. and this flow will be used in the reasonable potential
analysis.
A RPA was conducted for the following. Arsenic, cadmium, chromium, chloride, iron, mercury, nickel,
selenium, silver and zinc based on sampled data in discharge monitoring reports (DMRs) from January 2006
through December.2008. The RPA analysis is attached. (Note: Data for copper and iron were reviewed,
however since these limitations are required by federal guidelines, no changes were made.)
• Cadmium, Chromium and Silver The maximum predicted values demonstrated no reasonable
potential to exceed state water quality standards or acute criteria. Nearly all data were reported
below detection levels. Weekly monitoring will be deleted from the permit. No effluent monitoring
will be recommended in the permit since these do not appear to be parameters of concern.
• Arsenic, Mercury, Nickel and Chloride — The maximum predicted values demonstrated no
reasonable potential to exceed state water quality standards or acute criteria. Nearly all data were
reported above detection levels. Weekly monitoring will be deleted from the permit however
quarterly monitoring is recommended for these parameters because of the presence in the effluent.
• Selenium — the maximum predicted value indicated a reasonable potential to exceed both the chronic
and acute allowable concentrations. Based on this result, it is recommended that a weekly average
Emit of 29 ug/l and a daily maximum limit of 56 ug/l be added to the permit. Duke Energy has
requested a three year compliance schedule in order to meet the proposed limit for selenium. This
will be granted with milestones to be met during the term of the compliance schedule.
• Zinc — The maximum predicted value demonstrated a reasonable potential to exceed only the acute
allowable concentration. This is an N.C. Action Level standard and should be reviewed in
conjunction with toxicity testing. Duke Energy has passed all chronic toxicity tests for the past three
years. It is recommended that weekly monitoring can be reduced to monthly monitoring.
PROPOSED CHANGES:
Outfall 002
• Elimination of monitoring for: total cadmium, total chromium, total silver
• Monitoring reduced from Weekly to Quarterly for: total arsenic, chloride, mercury, total nickel
• Monitoring reduced from Weekly to monthly for: zinc
• Addition of limit of 29 ug/l (weekly average) and 56 ug/l (daily maximum) for selenium
Outfall 004
• Elimination of monitoring for: total cadmium, total chromium, total silver, and total suspended
solids
• Monitoring reduced from Weekly to Quarterly for: total arsenic, chloride, mercury, total nickel
• Monitoring reduced from Weekly to monthly for: zinc
STATE CONTACT:
If you have any questions on any of the above information or on the attached permit, please contact
Jacquelyn M. Nowell at 919-807-6386 or [e-mail].
In
Maushall Steam Station Fact Sheet
NP.DES Modification
Paae 6

REGIONAL OFFICE COMMENT:
NAME: DA
EPA REGION IV COMMENT:
NAME: DA
Marshall Steam Station Fact Sheat
NPDES Modification
Page 7

REASONABLE POTENTIAL ANALYSIS
Duke- Marshall Steam Station WWTP
NC0004987
Time Period 01/2006-1212008
Ow (MGD) 7.99 • WWTP Class IV
7010S (cfs) 60 IWC (%) ®7Q10S 17.109
7Q 10W (cfs) 60 @ 701OW 17.109
3002 (cfs) 0 ® 30Q2 N/A
Avg. Stream Flow, QA (cfs) ' 278 @ OA 4.2649
Rec'ving Stream Catawba River (Lake Norman) Stream Class WS -IV B CA
Outfall 2
Qw = 7.99 MGD
PARAMETER
TYPE
STANDARDS &
CRITERIA (2)
POL
Units
REASONABLE POTENTIAL RESULTS
RECOMMENDED ACTION
NC WQS / 14 FA III
Chronic Acute
n # Det Max Pred Cw Allowable Cw
(1)
Arsenic
C
10
ug/L
98 71
19.3
Acute: N/A
------------
Chronic 234
No reasonable potential shown Recommend weekly ,,.,'
monitoring be deleted. Quarterly.monitoring recommends
Acute: 15
No reasonable potential shown Only'one detectable value
Cadmium
NC
2 15
ug/L
97 1
1.4_
_ _ '
Chronic 12
Recommend ekly monito_nng be, dioppe_d:
in two years we
Effluent .monitoring will not be required
Chromium
NC
50 1,022
ug/L
96 2
1.8_
Acute: 1,022
_
Chronic_ _ 292
No reasonable potential shown.,. Only one detectable value
in two years Recommend weekly monitoring be diiopped:1
EfFluent morntonng will not be req ire °
Copper
NC
7 AL 7.3
ug/L
,5 3 32.6
Acute: 7
_ _ _
Eff•, Guidelines require copper limit; will leave in the permit.
:,
te criteria._ _
RPA`results show_exceedanc_e of ac--------------
Note: n<12
Note:
___
Chronic 41
Limited data set
Acute: WA
No reasonablepotential.shown._Ma)L pred. value. does not
Chloride
NC
250
mg/L
96 96
798.0
_
Chronic 1,461
exceed 6hr6ni6allowable.;'Recommend monitoring be ,`,.
reduced from weekly to quarterly
Acute: 0
Iron
NC
1000 N 0.001
ug/L
4 4
Note: n<12
1264.4
_ _ _ _ _
Chronic 5,845
_ _ _ _ _ __
Eff. Guidelines' require uon limit, will leave in the permit. "
Limited data
set
Acute: N/A
Mercury
NC
12
2.0000
ng/L
95 87
10.2382_
_ _ _ _
Chronic: 70
No reasonable potential shown to exceed chronic Atlowablei
Recommend that weekly mon be'reduced to quarterly '
Acute: 261
No reasonable potenial shown to exceed chronio or acute"
Nickel
NC
25 261
ug/L
96 96
34.5_
allowable Recommend reduceweeklymon toquarteriy`
Chronic_146
r
a
Selenium
NC
5.0 56
ug/L
100 99
90.4
Acute: 56
_ _ _ic _ _ _ _ 29
Cd
hron
Reasonable potential'shown,to exceed.both the'chronicand
acute allowable cons Reoo_mmend that a weekly_average!
an daily maximum limit be groen
Silver
NC
0.06 AL 1.23
ug/L
86 1
1.2'
Acute: 1
_ _
Chronic 0
No reason able` potential shown Only one detectable value
m two years Recommend weekly monitoring be drooped:,,
Zinc
NC
50 AL 67
ug/L
96 .96
84.6_
Acute: 67
_ _ _ _
Chronic 292
No reasonable potential to exceed chronic allowable but ,
RP to. exceed the acute cntena Recommend that weekly
monitoring be reduced to monthly
• Legend: " Freshwater Discharge
C = Carcinogenic
NC = Non -carcinogenic
A = Aesthetic
49B7rpa0020608.xls, rpa
3/17/2009

Data Data
BDL=I2DL Results
1 Jan -2007
4.65
4.7 Std Dev.
1.9583
2 :' .,
4.37
4.4 Mean
3.89&5
36.18
r:..-
6,2 C.V.
0.5023
..
4 ...
4.92
4.9 n
98
5
4.4
4.4
6' Jan -2008
6.07
6.1 Mult Factor=
1.3600
7
6.34
6.3 Max. Value
14.2
8t. `,
6.13
6.1 Max Prod C.
19.3
9
4.98
5.0
10
5.73
5.7
12 e'
5.17
5.2
13^
5.25
5.3
14-
4.15
15
6.03
6.0
16
4.51
4.5
17 },
5.52
5.5
.18 _ '
5.27
5.3
19
4.96
5.0
20
4.5
4.5
21'
6.78
6.8
22,,.
23
6.06
6.1
24 ",
S.
5.5
25 .;
5.65
5.7
26 t.
5.3
5.3
27
4.17
4.2
28
8.06
8.1
29
4.61
4.6
30 -
4.37
4.4
31 .
32
33 - _
4.14
4.1
34,'
4.01
4.0
35�'
4.9
•4.9
36 -
4.08
4.1,
37
5.39
5.4
38 P-
3.8
3.8
39
3.5
3.5
40 ,<
41
42
43„ _, -.... _
5.88
5.9
44
4.
4.0
45 -
3.97
4.0
46
2.58
2.6
47
2.5
2.5
481. -
2.2
2.2
49
4.27
4.3
50
4.8
4.8
51 :.
4.39
4.4
52' i
4.33
4.3
53
54,
26
2.6
55 -
2.5
2.5
56
1.8
1.8
57 ,.: .'
1.6
1.6
58 " `
4.93
4.9
59
1.9
1.9
60'21
2.1
61
2.4
2.4
62`
2.1
2.1
63
26
2.6
64 Oct -2007
14.21
14.2
65 ,
6.01
6.0 -
66, • '
4.38
4.4
67
4.3
4.3
68'
244.
2.4
69 i
5.13
5.1
70
5.93
5.9
71 ,
5.79
5.8
72!
5.29
5.3
73
25
2.5
74 ;
3.5
3.5
75 - "
5.14
5.1
76,
4.49
4.5
77,
4.99
5.0
78.
6.21
6.2 -
'
79- J
5.87
5.9
80
5.12
5.1
81 FebQ006
2.6
1.0
82 May -2006
2.0 .
1.0
83. Feb -2007
4.0,
2.0
841,. Mar -2007' K
4.0;
2.0
g5
4.0r
20
86 <
4.0
2.0
87"
4.0`
2.0
88'
4.0.
2.0
897
- 4.0'
2.0
90
, 4.0;
2.0
91
4.0-
2.0
92 May -2007
c .; 410,
93
4:0
2.0
94
4:0`
2.0
95
4.0
2.0
96
2.0
97' 'C
4.0;
2.0
REASONABLE POTENTIAL ANALYSIS
m
4987rpa0020608.xis, data
3/17/2009

98 Aug -2007
",:
;< -4.0. 2.0
99,..
4;0 2.0
100
4.0 2.0
101
4.0 2.0
102 Oct -2007
4.02.0
103 Apr -2008
z 4.0. 2.0
104
4.0 2.0
105
4.0 2.0
106 ..
_ 4`0 20
107 May -2008'
< 4.0, 2.0
REASONABLE POTENTIAL ANALYSIS
-2-
4987rpa0020808.xis, data
3/17/2009

REASONABLE POTENTIAL ANALYSIS
�6 17
4
3 I Copper
Cadmium
Chromium
4987rpa0020608.xis, data
3 3/17/2009
Results
Date
Data BDL=I2DL R ... Its
Data Date BDL -1211L
2.5
Results
Std Dev.
2.7523
1
Data Data
BDL=I20L
0.3 Sid De✓.
0.0920
1 Aug -2008
1.6
1.6 Sid Dev.
0.1986
1 <
5
2.5
Min
5.2000
2 -
1 , Dec -2006 .. ...
:.
0.5
0.3 Mean
0.4974
2. Sep -2008
1.5.
1.5 Mean
0.9385
2 <
5
6
6.0
C.V.
0.5293
3
2 ;•
3.� ..
O.Si
0.5:
0.3 C.V.
0.1849
3
fa
0.5 C.V.
0.2116
95
3
4
6
6.0
n
5
4
0.5
D.3 n
97
4 '
< 1
0.5 n
5
9
9.0
5
5 • ..
. 11
0.5
5
. 1
',1'
0.5
0.5 Mult Factor=
1.1500
6
Mult Factor=
3.6200
e•
61 Oc12007.yr.
1.25
1.3 Mult Factor=
1.1200
6
`'�
0.5 Max. Value
1.6 ug/L
7
Max. Value
9.0 ug/L
7
7 •-'
`'
•.1,
0.5 Max. Value
1.3 ug1L
7
< 1.,
` y
0.5 Max Pred Cw
1.8 ug/l.
8
Max. Pr d Cw
326 u9/L
e
e
. j;
0.5 Max Prod Cw
1.4 ug/L
8 �
<
9
9
9 <
1
0.50
S.
1,
'1•
0.5
10
10
0.50
10; •
G,
0.5
-
11
1p,
0.50
11
1•
1'
0.5
0.5
12
12
12
1
0.50
12 _
13',
<
J.
0.5
19 ..
13
14
13' -
1.
0.SD
14 •'
1:
0.5
14 ,.
-
15
14
1'
0.50
15 .
1;
0.5
15
16
15 <
1
0.50
16
< 1.1
0.5
16
17
1:'
1..
0.50
0.50
"
17
t • 2.0,
1.0
18
18
17
,4
1
0.50
18
t' 2.0�
1.0
19
19
18
19
1
0.50
19.
'.
2.0,
1.0
20
- ..
20
0.50
20 • ,
< .. 2.0�
1.0
21
21
21 :<'
1
0.50
21 •
c 2.0
1.D
22
22'
1
0.50
22
< •2.0
1.0
23
23
,Y
23
1
0.50
23'
< 20;
1.0
1.0
24
24
24 - <
1
0.50
24 ,
2.0'
2.0
1.0
25 '.
2r,
25 ...<
1
0.0.50
25,
26 � -
', 2.0
1.0
26
26
27
., '
50
27'
2.0,
1.0
27
28
27 ,
1
0.50
28 "�,-:
2.0
1.0
28
29
28
d..
11
1
0.50
O.so
29
.< 20'
1.0
30
29 -
30 ..
,11
0.50
30 _
2.0:
1.0
30
31
31
_
31
1
0.50
.:
31
< 2.0'
1.0
32
32
32
1
0.50
32
c 20�
2.0'
1.0
1.0
33
33
33 '_
�G
1
O.SD
33
34 "
< 20
1.0
34
-
34
35
34 -
1
O.so
35
20
1.0
35
.36
35 z
1
0.50
36
- 2.0'
1.0
36
37
36 , . c
1
1
0.so
0.50
37
20
1.0
37
,
38
37 .. .
38 •
1
0.50
,.
38
...:
< 2.0'
1.0
38
39
39
�`
39
1,
0.50
39
. 2.6
9.0
1.0
�
40
40
1
0.50
40
41 '
2.0
�< 2.D
1.0
41
:
41
42
41
1
1
0.50
0.50
42
C . , 20
1.0
42
q3
42 <
43--- .. __ ___
"1
0.50
43, , .,-.. _. ""�
43
44 _.. _
_ �.,
44
44 c
1
0.50
44
-2.0
< '2.0
1.0
45
-
45
45
1
0.50
45
1.0
46
46
46
1
0.50
46
< 20
1.0
1.0
47
•
47
47. `<
1
0.50
47
`
< _ - 20,
1.0
48
48
_ ..
48 <
1
0.50
411 "
< 2.0
49
49 <
1
0.50
50.
50
50
7
0.50
50e
2A.
2.0;
1.0
1.0
51
51
-
51
y
0.50
51.-.a
52
_
2.0
1.0
52
52
53
52
1
0.50
53
2.0�
1.0
53
54
S3 K
1
0.50
54
< 20
1.0
54
55
54 <
1
0.50
55l
' 2.0
1.0
66
56
55
1
0.50
56
20
1.0
58'
57
56 <
1.
0.50
571
2.0
1.0
67
58
57
1
0.50
58
_
4 20
1.0
58
59
58
1
0.50
59
-
<,.• 2o;
1.0
59
60
59
1
0.50
,.,
60,.,..
•2.0,
1.0
60
61
'
60 .. i
1
0.50
61 -
G 2.0�
1.0
61
62
61<
7
0.50
62 �:.',
,.2.01
1.0
62
'
63
62 - <
1
0.so
63,
` 2.0'
1.0
83
64
63
1
1
0.50
0.50
64
< 2.o
7.0 -
64
.
65
64
_
1.
0.50
65
. 2.0
1.0
65
66
65
66 <
1
0.50
66
< 20
1.0
66:,
67
67
67
7
0.50
67 ,
2.0
20'
1.0
1.0
68
68
0.50
68
69
20
1.0
69
69
70
69
1
0.50
70
,. 2.0
1.0
70
71
70 -
1.
0.50
71
2.Oj
7.0
71
72
71 <
1
0.50
0.50
72
.2.11.
1.0
72
73
72 < ..
<
.. 1'
• 11
0.60
73.
:2.0
1.0
73
74
73 _
.
1
0.50
74
2.0'
1.0
74
75
74',
1
0.50
75
< 2.0
1.0
75
76
75 :<
76' <
1�
0.50
76
2.0
1.0
76
77
-,
77
77 -
- 1
0.50
77
zo"
1.0
1.0
79.
78
78
1
0.50
78
79:
.2.0;
E : q 2.0,
1.0
79.80
79
79,
1
0.50
8o
2.0:
1.0
BO'
81
80 -
1
0.50
81 ..
2.0�
1.0
B1
82
et .
1'
1
0.50
0.50
82
<. ..2.D,
1.0
B2
83
82
83;;
2.0•
1.0
83
84
83 e,
1
0.50
,
84
,
2.0:
1.0.
84
85
84
1,
0.50
85
2.0
1.0
85
86
85 " <
.. 1
0.50
86
2.0:
1.0
86 -
87
e6... ,..
1;
..1
0.50
87
88
87':
0.50
BB
< 2.0'
1.0
8B
89
88 •. a
+ 1'
0.50
89
< 2:0,
1.0
B9 ,
90
89',
1
0.50
90
< - 20•
1.0
90
91
90 <
1
0.50
91.
2.0:
1.0
91
9'L
91 <
1
1
0.50
0.50
92'-•
_
< 2.0•
"'
1.0
92
_
93
92
`
93
1.
0.50
93;
... 2.0i
1.0
93
94
"•
94
94
'1
0.50
94,.
•• 20:.
1.0
1.0
95
'95
95 > .- s <
.; L
0.50
95' ,
2.0',t
[ 2.0.
1.0
96
. _
96
0.50
96'"
-
97
_
97
97
0.60
97
4987rpa0020608.xis, data
3 3/17/2009

REASONABLE POTENTIAL ANALYSIS
99
1
98'
100 i t
99
100 - '
99 '
98
99
101,",
-
101,
100
100
102:
•
02-
101''
101
103 r
103
102
102
104 ,
1 04
03
103
105•
105 ..
104
104
106.1 _
106
105 ,'
105
107? ,,
107'
106• .
10 7
106
107
4-
4987rpa0020608.xls, data
3/17/2009

Chlorlde
Data BDL -1120L Results
4.86 4.9 Sid Dev.
11.2 11.2 Mean
26.1 26.1 C.V.
41.42 41.4 n
63.2 63.2
76.9 - 789 Mull Factor=
124.3' 124.3 Max Value
97. 1
97.1 Max. Fred Ow
111.27 111.3
91. 91.0
87.8 87.8
99.5 99.5
98.59 98.6
98.18 98.2
78.31 - 78.3
118. 118.0
1 02. 6
102.6
69.96 90.0
172. 5
1725
188.1 188.1
117.56 117.6
145.6 145.6
168. 168.0
128.85 128.9
206.8 206.8
213.1 213.1
260. 260.0
314. 314.0
297.7 297.7
272.1- 272.1
360.1 360 .1
255.2 255-
291.8 291.8
323.7 323.7 ,.
290.3 290.3
256.1 256.1
358.8 358.8
386.5 386.5
346,8 346.8
334.9 334.9
297. 297.0
357.4 357.4
295.1 295.1
344. 344.0
249.2 249.2
359. 359.0
314. 6
314.6
3226 322.6
351.4 351.4
368.9 368.9
336.7 336.7
255.6 255.6
340. 340.0
380. 380.0
480. 480.0
310. 310.0
490. 490.0
410. 410.0
350. 350.0
310. 310.0
460. --
-270. 270.0
600. 600.0 '
460. 460.0
410. 410.0
530. 530.0
450. 450.0
460. 460.0
_ 450. 450.0
420. 420.0
270. 270.0
320. 3200,
310. 310.0.
300. 300.0
340. 340.0
390. 390.0
340. 340.0
280. 280.0
280. 280.0
310. 310.0
340. 340.0
410. 410.0
370. 370.0
340. 840.0
300. 300.0
°'r.: 360. 360.0
360. 360.0
280, 280.0,
360. 360.0
_
-280 280.0
310. 310.0
180. 180.0
210. 210.0
200. 200.0
270. 270.0
250. 250.0
125.9902
276.0448
0.4564
96
1.330D
600.0
798.0
REASONABLE POTENTIAL ANALYSIS
Data Data BOL=I2DL Results
1 Apr 2008 382 382.0 Std Dev.
24 317 377.0 Mean
3 124 ' 124. 0
C.V.
4y
234 234.0 n
b
Mutt Factor=
7 ' Max. Value
Max. Fred Cw
11
12
13
14
15
16
17
18
19
20
21
24
25
31i
32
34,
35
36
37
39
40
41'
42,1, yes
44 S`
45 :S
46
47 §
48
49
50
51'
-5-
124.1810
279.2500
0.4447
4
3.3100
382.0
1264.4
Data
1 iDe�-2008
2
3l D.2008
4
5 �t
6.'.�' ..-..
95
96
97
BDL=120L Results
1.0 Sid Dev.
1.0 Mean
1.0 C.V.
1.0 n
25
21 Mutt Factor=
2.6 Max. Value
2.2 Max. Fred C-
1.0
2.5
3.4
2.7
2.5
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
B 1.0
2 2.5'
8 1.0
7 1.0
63 1.0
4 1.0
8 1.0
2 1.0
1 2.2
95 3.0
2 2.7
q4 2.4
8 2.8
2 3.0
1 2.9
9 2.3
2 3.4
3.1
9 26
22 5.2
3 3.1
8 3.3
44 24
9 1.0
59 1.0
36 3.4
75 2.8
82 3.8
04 3.0
44 24
55 3.6
21 7.2
94 29
92 29
.6 1.0
.9 1.0
73 4.7
2
27 2.3
76 2.8
32 3.3
86 1.0
62 2.6
76 28
85 2.9
.52 1.0
.83 2.8
2.4 24
.49 2.5
.66 1.0
.71 1.0
.83 1.0
1.9 1.0
.89 29
.05 3.1
58' 2.6
34 2.3
.12 2.1
.73 1.0
.54 1.D
.15 1.0
.65 1.0
.24 1.0
1.03 1.0
1.28 1.0
1.4 1.0
1.0
1.0
1 0; 1.0
,01 1.0
1.0
1.8
2.5
2.1
2.6
2,2
1.4
25
3.4
2.7
2.5
1.9
1.4
1.5
1.1
1.4
1.7
I.
i.
1.4
1.7
1.
2.5
1.
1.6
1.
t.
1.1
1.4
2.2
2.
27
2.
27
3.0
2.9
2.2
3.43. OB
2.5
5.
3.1 2
3.
2
1
1.
3.
2.
3.
3.
2.
3.
7.
2.
2.
1
4.
4
.2 4.
2.
2.
3.
1.
2.
2.
2
1
2
2
1
1
1
2
9
2
2.
2
1
1
1
1
1
1.1723
20183
0.5808
95
1.42
7.2
10.2
1
2
3
4
5
6
7
8
10
11 _
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
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
t0
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
4987rpa0020608.xis, data
3117/2009

REASONABLE POTENTIAL ANALYSIS
1
99
-
99
98
100
99
r
100,
100
102! •
101.
'
103'
102' •
102
..
104 , -
104•
103
IM : _.
.,•'
104
I . `
106.",.,
105
105
.. -
107 _''
106 ..
106
107 • ... _,.,
107
-6-
4987rpa0020608.Xis• data
3r17/2009

8 �N E;.. . .. .
9, r, P PPIP P
P P p.
b. 6 o 6 b j� b, 6 b b b, 6 �4 �4 bD �O �4 L4
NNNL4
;4
W—M!
k zg
bl '44 Nl b. 01 ill bl
7: jG In — — — — — — — 74 5. 91 91 P
�t jG p �4 91
6 bo i� b, 6 b, 6 kl 44
P
8- 4
. i" 1 otos
44 o. P4 A A t, t.
E3Eg&52 Eggs !28"."V13 Z?l W N rs
lb
. . . . . . . . . . xwqzi
. . . . . . . . . .
O
-- — — --- — — — — — -- --- - — — - —
N 6 NN .6 N N NN 6 6 NO i. NO -66 m 6 .6
90 p
.A gCcH.l
E

REASONABLE POTENTIAL ANALYSIS
g.
4987rpa0020608.xis, data
3117/2009
98 2.3 2.3
98
99 2.5 2.5
99'
98
100 3.7 3.7
100 ..
99
r`'
101 5.4 5.4
• .
101,
100
-
102!1.
102'
101
•
103' • .
103
104'
104
. .
5
105'
105:. "
104
ar'W
i +
106;'
105
107
107.,
los
.
,. , .. ..
107
g.
4987rpa0020608.xis, data
3117/2009

_ crno
Date Data- BDL=I2DL Results
29.0 Std Dev.
11.6927
. 23;
23.0 Main
20.4270
16!
15.0 C.V.
0.5724
20'
20.0 n
96
i
22
22.0
l?.
24.11
24.1 Mutt Factor=
1.4100
'�" •+ ' `"
'
18.07
19.03
18.1 Max Value
19.0 Max Prod Ow
60.0
84.6
20.1
20.1
;..`a
22.78
22.8
„}
14.45
16.21
14.5
16.2
17.65
17.7
21.3
21.3
22.74
22.7
_-
23.15
23.2
17.61
17.6
_
ar-.Fc-
24.1
24.1 -
25.85
45.74
25.9 -
45.7
•'""30.77
37.37
37.4
30.6
"
45.73.
..45.7
46.23
46.2
•f,';,
58.54
58.5
53.01.
53.0
42.02
420
33.93
33.9
22.93
229
19.
19.0
-• R �`
26.6
26.6
28.41
28.4
38.19
38.2.
_
-
27.64
27.6
_
"
16.71
16.7
t.. 3
13.67
_
13.7
6.916.9
"
10.68
10.7
11.84
11.8
11.52
11.5
8.2
8.2
'
9.43
9.4
10.27
10.3
"
13.05
13.1
9.26
9.3 -
�'`•.;
;.:, ,, :......
10.62
9.5
10.6
.9.5
10.18
10.2 '
11.84
11.8
'
10.93
-10.9
10.7
10.7
8.33
8.3
8.79
8.8
10.
10.0
10.3
10.3
'
9.86
9.9 ,
15.8
15.8
17.7
17.7
19.4
19.4
15.8
15.8
15.
15.0
21.1
21.1
21.1
21.1
19.4
19.4
•_.;
15.6
15.6
7: _
14.6
14.6
16.
16.0
26.2
262
�.'t
26.2
27.4
26.2
27.4
N •':',..
23.3
23.3
20.4
20.4
17.
17.0
15.315.3
27.1
27.1
24.5
24.5
20.4
20.4
'
11.7
11.7
11.4
11.4
5.37
5.4
5.14
5.1
3.8
3.8
3.3
3.3
8.53
6.5
22.7
22.7
14.4
14.4
11.3
11.3
2,
-
11.9
11.9
8.9
8.9
1.
31.5
31.5
�2 Sep-2008•.,
27.7
60.
27.7
60.0
43.1
43.1
_
28.4
28.4
}. d
30.5
30.5
19.2
19.2
REASONABLE POTENTIAL ANALYSIS
4987rpa00206De.xls, data
- 9 - 3117/2009

REASONABLE POTENTIAL ANALYSIS
10-
4987rpa0020608As, data
3/17Y2009

selenium
Subject: selenium
From: Connie Brower <[e-mail]>
Date: Tue,13 Jan 2009 13:57:44 -0500
To: Jackie Nowell <[e-mail]>
Hi Jackie
To follow up with yesterday's questions -- The selenium information is highly likely
to take a number of years to be formally adopted by the EPA. They have promised this
for years -- and have withdrawn the proposal a number of times since -1984. . With
that said, it is also highly likely that the number, based upon fish tissue
concentrations will be lower than what we currently have.
If EPA progresses with its current path, the number would be a fish -tissue criterion.
This criterion would then be back calculated to a water column concentration for
permitting purposes. Because selenium bioaccumulates; the permitted facility would
or the State would? ) need to identify the relevant Bioaccumulation factor for the
receiving water... a daunting task... OR we would choose to assume that the receiving
stream contained a fish that COULD bioaccumulate to the highest level observed in
national or regional studies -- also daunting... restrictive, and controversial.
So, until this happens -- we will retain the current standard.
hope this helps -- call if you need more....
connie
Connie Brower <Connie.Brower(a,ncmail.net>ULV ®0
Industrial Hygiene Consultant 1 , ,n dvt [ i�� S
NC DENR I r r� Q
Division of Water Quality G D VJ
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1 of 1
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1/13/2009 -4-N

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NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Beverly Eaves Perdue Coleen H. Sullins Dee Freeman
Governor Director Secretary
February 10, 2009
MEMORANDUM
To: Britt Setzer
NC DENR / DEH / Regional Engineer
Mooresville Regional Office
From Jacquelyn M. Nowell
DWQ/NPDES Western Program