NC0024406_Permit Application_20060831

µ : Duke
Energy
August 29, 2006
Mrs. Carolyn Bryant
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
Point Source Branch
1617 Mail Service Center
Raleigh, North Carolina 27699 -1617
Duke Energy Corporation
526 South Church St.
Charlotte, NC 28202
Mailing Address:
PO Box 1006
Charlotte, NC 28201 -1006
Subject: Duke Power Company LLC — NPDES Permit Application
Belews Creek Steam Station - #NC0024406
Dear Mrs. Bryant:
Duke Power requests the subject permit be renewed and reissued. The above
referenced permit expires February 28, 2007. As mandated by North Carolina
Administrative Code 15A NCAC 2H.0105 (e), this permit application for renewal is
being submitted at least 180 days prior to expiration of the current permit.
Please find enclosed in triplicate, the renewal application, which includes the
following items:
EPA Form 1
EPA Form 2C
EPA Form 2F
Site Map
Water Flow Diagram
Supplemental Information
Duke Power requests notification that this application is complete.
Additionally, the attached report, "Assessment of Balanced and Indigenous
Populations in Belews Lake," continues to indicate recovery of aquatic populations
and includes a request to approve recommended monitoring program modifications
going forward. Therefore, this report also supports renewal of the current thermal
monitoring requirements of outfall #001.
www.duke- energy. corn N

Duke Power requests that all temperature limits for outfall #001 be expressed
solely'in degrees Fahrenheit or Celcius to eliminate confusion.
The following monitoring reductions at outfall #003 are requested based on
historical monitoring data, which are attached. The suggested methodology
changes are based on the Steam Effluent Guideline in 40 CFR 423.12.
• Reduction of monitoring of Total Copper and Iron from quarterly to
occurrence of a chemical metal cleaning.
• Reduction of Oil and Grease from quarterly to once /per six months.
• Reduction of Total Suspended Solids from quarterly to once /per six months.
• Reduction of Total Nitrogen from quarterly to once /per year.
• Reduction of Total Phosphorous from quarterly to once /per year.
Thank you in advance for your assistance on ,this matter. Should you have
questions regarding this application, please contact me at (704) 382 -4309.
Sincerely,
Allen Stowe,
Scientist, Water Management
Attachments
cc w/: Mr. David'Russell - NCDENR Winston -Salem R.O.
Ms. Trish MacPherson — NCDENR, Raleigh, N.C. (BIP Report,3 copies)

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FIGURE 1. USGS TOPOGRAPHIC *MAP OF THE AREA
AROUND BELEWS CREEK STEAM STATIONS
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Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
General Information
Belews Creek (BC) Steam Station is a coal -fired electric, generating plant operated by Duke Power
Company BC is located on,Belews Lake at NC County Road 1908 - approximately eight miles northeast
of Walnut Cove in Stokes County near Winston - Salem, North Carolina.
System descriptions and a line drawing showing the water flow-through BC follow,'indicating sources of
intake water, operations contributing to the effluent, and treatment provided. Other flows on the line
drawing-and in a brief narrative description of sources contributing to each outfall effluent that follows
are an approximation of average daily station operation by operators
®UTFALL 001 — CONDENSER COOLING WATER (CM)
Raw water-from Belews Lake is passed through condensers and auxiliary equipment on a "once -
through" basis to cool equipment and condense exhaust steam from the turbines. Cooling water
passes through a network of tubes in the condenser and 'selected heat exchangers (e.g. turbine
lube oil,coolers, condensate coolers, miscellaneous closed system coolers). This•raw water in the
condenser tubes absorlis heat from a closed system of highly purified exhaust steam from the
turbines and converts it back to water. The condensed exhaust steam is returned to the boilers
and recycled in this loop a number of times. The raw cooling water is returned to the lake. No
chemicals are added and only heat rejected from the condensers and auxiliary equipment is
absorbed, hence the term "once through, non - contact cooling water" is applied.
The condensers,at BC are cleaned mechanically,. Normally„ amertap balls clean the tubes on a
continuous basis while the plant is operating Periodically, metal scrapers, plastic scrapers or
rubber plugs are forced through the tubes to nd them of scale, or other deposits.
Each unit at BC has four condenser cooling water (CCW) pumps Pump capacities are listed in
the table below Normal plant operation of the CCW pumps is based on intake and discharge
temperatures and unit load. The maximum pumping, capacity is 1457.28 MGD, and the average
CGW flow for 2005 was 1326 MGD. To avoid a system trip that would suddenly reduce the
discharge flow at outfall 001, each unit is on an independent system This practice leads to
higher reliability factor for the units and protection of aquatic life taking refuge in the discharge
canal during-cold weather.
No. of Pumps Total Flow Intake Temperature
(gpm) ( °F
1 184,000
2 3339000 <61
3 444,000 61 -69
4 506.000 >69

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Intake Screen Backwash
Each unit has 4 stationary intake screens (18 ft x 23 ft) which are removed for cleaning The
intake screens are backwashed as needed -at a rate of 500 gpm for approximately five minutes
each The total volume of water used is 0.02 MGD. This intake screen backwash'is discharged
back into the station,intake. The debris is collected within a,cleanmg basin and consists mainly
of twigs, leaves, and' other material indigenous to Belews Lake, The collected debris is removed
,and composted.
Recirculated Cooling Water (RCW) System
'The Recirculated Cooling Water (RCW) system is a closed loop cooling water system.
Depending on the temperature of the raw lake water and the operation of BC, once through non-
contact condenser cooling water is passed through the RCW coolers to maintain the closed loop
cooling water within the RCW system at <95 °F. The RCW system supplies cooling water to
various equipment and is composed of a storage tank, three 50% capacity RCW pumps, two
100% capacity heat exchangers (RCW coolers), and associated piping and valves for the two
units. Recirculated cooling water is supplied from the CCW system to the RCW storage tank
(capacity of 19;000 gallons) and makeup water is added, as required per tank level and
temperature controls. The maximum flow of CCW through each of the two RCW coolers is
5360 gpm or 7.72 MGD. Non - contact cooling water discharged from the RCW coolers
combines with the�condenser cooling water and,is discharged from outfall 001.
The RCW system contains maintenance, chemicals in order, to prevent corrosion. The primary
chemical used in the RCW system is sodium nitrite. Microbioddes;are, also used at very low
concentrations. The potential, exists for the RCW system to have minor tube leaks, due 'to
material corrosion. Tube leaks from the RCW system discharge into the CCW system, which
discharges, into Belews Lake `through outfall 001. Routine monitoring of the RCW system for
nitnte concentrations and the inventory of make -up water provides input that assists in
determining a tube leak. Once a leak is identified, corrective,, measures are-implemented to
minimize and repaired the leak. During routine maintenance the'process water from the RCW
system drains to_ floor drains where it is pumped to the ash basin (outfall 003.) During a leak
and/or routine maintenance, the concentration of the maintenance chemicals will not exceed the
No Observed Effect Concentration (NOEL) at either outfall 001 or 003
2

Belews Creek, Steam, Station, Stokes County
NPDES Permit 4NC0022406,
Hydrogen and Oil Coolers
Once through non - contact cooling water is supplied from the Low Pressure Service Water
System that draws water from the CCW system to hydrogen and oil coolers. The system consists
of two High Pressure Generator Hydrogen Coolers (maximum combined flow of 3,990 gpm),
four Low Pressure Generator "Hydrogen Coolers (maximum combined flow of 3520 gpm), and
two Turbine Lube Oil Coolers (maximum combined flow of 7400 gpm) for each unit. A
maximum of 43:0 MGD of cooling water can flow through these coolers when both BC units are
operated at full load. Discharge from these coolers combines with the condenser cooling water
flow and discharged at outfall 001.
Station Equipment Cooling Water
Once through non- contact cooling water is supplied from the Low and High Pressure Service
Water System to the bearings of the induced draft (ID) fans to remove excess heat. No chemicals
are added to the once through raw lake water discharged to Belews Lake. The rate of flow
through the control equipment is approximately 0. 86 MGD when both BC, units are operated at
'full load This effluent also includes chiller once through water.
Outfall 002 — Me Gas Desulfurization Treated Waste Water (Internal
NPDES Outfall)
The. installation of a Wet Flue Gas Desulfurization (FGD) system'is currently underway at
Belews Creek for the reduction of Sulfur Dioxide (S02) from the stack gas. This system is
expected to be operational in January 2'008. The FGD system follows the electrostatic
precipitators (which removes fly ash) and also the Selective Catalytic Reduction (SCR) systems
(which uses anhydrous ammonia for nitrogen oxide (NOX) control). The use of this equipment
will entail use of or production of. calcium sulfite, vanadium pentoxide, calcium carbonate and
sulfur
Sulfur Dioxide is'produced from the coal combustion process The FGD system removes S02 by
,areaction using a limestone -water slurry. The FGD system will collect,the flue gas after it
passes through the electrostatic precipitator and route the gas to the absorber tank. As the gas
rises through the tank to the outlet at the top, the gas passes through a spray header. An atomized
slurry of water and limestone droplets is continually sprayed through this header into the stream
of flue gas. The S02 in the flue gas reacts with the calcium,in the limestone and produces
calcium sulfite (CaS;03). This CaS03 slurry falls to, the 'bottom of the tank where a stream of air
is injected to oxidize the�slurry to form gypsum (CaSO4•H20). The gypsum slurry is drawn off
the absorber tank and pumped to a hydrocyclone where solids are removed and part of the slurry
is sent to a vacuum belt filter for dewatering. The solids (gypsum) may then be used in making
wallboard.
3

Belews,Creek,Steam Station, Stokes,County
N PD ES' Permit. #N C0022406
Part of the slurry is blown down to primarily keep the FGD chloride concentration below 12,000
ppm. This water is sent to a wastewater treatment system in order to remove solids, metals and
reduce the temperature. Initially thewastewater is sent to an equalization tank to allow for a
more constant flow and solid loading to the next treatment steps. The waste water, from the
equalization tank is pumped through three reaction tanks where pH is adjusted, metal treatment
and coagulation occurs. After the treatment occurs in the reaction tanks, the wastewater is sent to
two clarifiers in order to reduce the solid loading. Once the wastewater leaves the clarifiers the
pH is readjusted and the wastewater is cooled by a heat exchanger. The treated wastewater is
then pumped to a two stage biological treatment system in order to reduce the selenium
concentrations. Leaving the biological treatment system the treated wastewater is mixed with the
cooling water,from the heat exchanger in order to reduce the chloride concentration. This treated
wastewater is then pumped into a two train 18 acre Constructed Wetland. Treatment System
(CWTS). This treated FGD wastewater, is then discharged to the, ash, basin via outfall'002.
OUTFALL 003 - ASH.BASIN
The ash basin accommodates flows from the power house sumps, yard holding sump, ash sluice
lines, the chemical holding pond, the coal yard sumps, and rainfall run -off from the watershed of
the basin. Seepage from the toe - drains at the base of the ash basin dikes goes to the Dan River.
The toe - drains are needed to allow, as designed, seepage to occur from the earthen dikes. This
ensures the structural integrity of the dikes
Yard Molding Sump
Wastewater can accumulate in the yard holding sump from the power house sumps,, the
condenser feedwater system, and the coal yard sumps. 'During a boiler cleaning, this wastewater
accumulate in the yard holding sump and tare then pumped to the chemical holding pond.
4

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Power House Sumps
The Power House Sumps discharge to the yard holding sump and include wastewater from water
treatment equipment, floor wash water, equipment cooling, water, and miscellaneous leaks. The
Power House Sump receives wastes from the following systems:
❑ Water Treatment System
The water treatment system ,consists of one retention tank, three pressure filters, two activated
carbon, filters, _one Reverse Osmosis (RO) syeem, and one set of make up'demmeralizers. The
pressure ,filters each have a capacity of `250 gpm. Filters are backwashed twice daily. The
pressure filter media is composed, of rock and sand, therefore all backwash discharge is organic
buildup from the service water.
Make up demmeralizers are operated in, sequence (one cell at a time). Regeneration of these
cells is, required approximately every 40 days. Each regeneration requires 120 gallons of 66°
Be sulfuric acid and 600 gallons of 50% sodium hydroxide. An average dilute waste chemical
and rinse flow ,of 0 34 MGD is realized (for two hours per regeneration). The diluted acid and
caustic are discharged to the yard holding sump and then pumped to the ash basin. The useful
life of the resin varies and when replacement is needed the spent resin is sluiced to the ash
basin
The RO system is cleaned on an as needed basis using Osmonics AD -20 (275 lbs), Biomate
MBC 781 (2.5 gal), sodium laury"lsuffate (10 lbs) and sodium-,hydroxide (4 L).
❑ Condensate Feedwater System
The condensate feedwater system provides continuous flow - through boiler,feedwater to BC
supercritical pressure boilers. Condensate polishing demmeralizers of the powdered resin type
,are used to filter feedwater. The mixed anion- cation powdered resin provides filtering. and ion
exchange: Spent resins and associated wastes are, pumped to the ash basin for treatment and
disposal.
❑ Evaporative Losses, Soot Blowing
Exhaust steam from the turbine is used periodically to blow soot off the outside of the boiler
tubes. Thus, some of the condensate feedwater is. evaporated,in the boiler.
5

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
❑ Turbine and Boiler Room Drain System
Turbine and boiler room drains receive flow from once through non- contact,coolmg water of
the Station air conditioning system, the fire protection system, washdown, and miscellaneous
Station uses
❑ Station Air Conditioning
Once through non - contact cooling water is supplied from the Low Pressure Service Water
System to cool the Station air conditioning equipment. A maximum combined flow of 3.46
MGD of cooling water can flow through two chiller units. No chemicals are added to the
once through raw lake water that drains to the Station sumps where'it is pumped to the ash
basin.
❑ Fire Protection, Washdown, and Miscellaneous Station uses
The fire protection system, washdown; and miscellaneous station uses from,closed system,
drainage, cleaning, and testing can contain*
Corrosion inhibitors, e.g. Calgon CS and Betz, Powerlme 3201
Biocides, e g Calgon H -300 and H -510
Laboratory wastes
Cleanings (e g. small heat exchangers) Dispersant, e.g. polyacrylamide
Wetting agent, e.g. sodium lauryl sulfate
Detergent, e.g. tri= sodium phosphate.
Leak testing, e g disodium fluorescing dye
Miscellaneous system leakage's (small leaks from,pump packings and seal's, valve seals, pipe
connections)
Moisture separators on air compressor�precipitators
Floor wash water
Emergency firefighting water
Ash sluice system overflow
Low Volume Wastewater.
❑ Groundwater (GW) Remediation
A GW remediation_is presently underway to recover free petroleum product that leaked from a
underground, storage tank. A total fluids recovery system is used to recover contaminated
groundwater and free product from the site Remediation system equipment is used to remove
the petroleum-from the recovered groundwater, and the,reclaimed petroleum is, transported
off -site for treatment while the,treated wastewater is discharged to the ash basin via the,power
house sump A maximum flow rate of approximately 0.03 MGD is discharged to the ash
basin from the groundwater remediation system.
C.1

Belews Creek Steam Station, Stokes County
NPDES'Permit #NC0022406
❑ Fly and Bottom Ash Sluicing
Electrostatic precipitators are used to remove fly ash from the stack gases. The ash is treated in
the flue gas ductwork with S03 conditiomngto improve removal efficiency. Typically, the dry-
fly ash captured in these pteciprtators is collected,in temporary storage silos for subsequent
disposal in a permitted on -site landfill or for recycling in off -site ash utilization projects If the
system that collects the dry-fly ash is not operating, then the fly ash can be sluiced to the ash
basin. Bottom ash from the boilers is usually water sluiced to holding cell's for recycling
activities per reuse permit #WQ000721J. In, the case of equipment failure or immediately
following -an outage, service water is used to sluice the ash to the ash basin.
Electrostatic precipitators are normally cleaned by mechanicallyrappmg the wires and the plates
inside the�pfecipitaior- Before major precipitator work is performed they are cleaned by awash
down. The wash water is pumped to the ash basin from the yard drain sumps.
As contingency measures, if the levels of,regulated parameters are increasing one option that may
be periodically implemented is to sluice service water (from Belews Lake) to the ash basin to co-
manage the�various wastestreams that are discharging to the ash basin.
Coal Yard Sumps
The coal yard covers approximately 51.5 acres. The average rainfall run -off is 0.08 MGD. This
run -off is based on 40 inches of rain per year with 50% run -off. During winter, freeze
conditioning agents (i:e. diethylene glycol) maybe added to coal by a vendor prior to shipment or
sprayed on the coal pile to prevent freezing. Based on an application rate of two pints of 50 ppm
diethylene glycol per ton of coal and 10;000 tons of coal per °train load, the addition of freezing
agents will not significantly alter the coal pile run -off wastestream and the discharge of the ash
basin at outfall 003.
Most of the coal yard drains into the ash basin near the point of ash influent. Floor washwater
from equipment in the coal handling area and the remaining drainage from the coal yard flows ,to
the coal yard sumps where it is then pumped to the ash basin.
Consolidated Sump
The consolidated sump includes wastewater from the sanitary waste system, the storm water
collection pond, the limestone, unloading facility sump and wastewater from the, dry fly ash and
gypsum landfills.
The sanitary waste from the plant receives primary treatment in a 600,000 gallon capacity aerated
lagoon The lagoon discharges to a concrete chlorine contact chamber. To polish the effluent,
the sanitary waste system routes, a circuit of water•treated with chlorine `to the consolidated sump
which is routed to the ash basin. The expected flow from the sanitary treatment system is less
than '1,0,000 gpd.
7

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
The storm water collection pond collects storm water runoff from the gypsum and limestone
stockpiles as well as some of the limestone track area around the unloading facility. If the pumps
for the sump fail, there is an overflow to Belews Lake, possibly resulting in intermittent
discharge.
The two on -site landfills (ash and gypsum) are being constructed at Belews Creek. These
landfills will be located south east of the power station. The leachate and the runoff from these
landfills will be collected and pumped to the ash basin. FGD residue material that is not suitable
for beneficial use will be placed in the gypsum landfill. In addition to this material, material will
be removed from the clarifier stage of the wastewater treatment system, filter pressed and placed
in the landfill. Both landfills will begin operation in 2008.
Ash Basin Run -Off
Non -point sources of storm water to the ash basin include coal pile runoff. Based on forty inches
of rain per year with fifty percent run -off, and the watershed area of the ash basin, the yearly
average rainfall run -off to the ash basin is 0.47 MGD.
Boiler and Filter Cleaning Wastes
BC has two supercritical boilers that are cleaned on an as needed basis. Tube inspections are
done during outages to determine when cleaning is needed. The chemical cleaning wastes are
pumped to the chemical holding pond. After proper treatment, the pond effluent is discharged
into the ash basin at a controlled rate to provide further treatment. The chemicals and
approximate amounts for one boiler cleaning is as follows:
BOILER CLEANING CHEMICALS & AMOUNTS USED PER UNIT
Chemical Amount
Hydroxyacetic acid
50,312 lbs
Formic Acid*
20,598 lbs
Ammonium Hydroxide`(26 °Be')
2,063 gal
Ammonium Bifluoride*
4249 lbs
Hydrazine
718 lbs
Corrossion Inhibitor (Proprietary)
500 lbs
The Reverse Osmosis (RO) system is used treat raw water from Belews Lake. The RO system is
cleaned approximately 3 -4 times per year. The RO cleaning wastes are pumped to the ash basin.
Chemicals and approximate quantities for one RO cleaning are listed below:
E=l

Belews Creek Steam Station, Stokes County,
NPDES Permit #NC0022406
REVERSE OSMOSIS (RO) SYSTEM
Chemical Amount
Osmomcs AD -20
2,75 lbs
Biomate MBC 781
2.5 gal
Sodium Laurylsulfate
10 ibs
Sodium Hydroxide*
15 gal
The condensate polisher filters arecleaned with sodium hydrosulfite approximately once per
year The chemical and'approximate quantity used per year for this cleaning is listed below:
Chemical Amount
Sodium Hydrosulfite 3000 lbs
* These chemicals are present in amounts greater than the reportable quantity as identified
under the Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA) If a spill of any these chemicalsvere to occur, inmost cases, the spill
would be routed to the ash basin for treatment. These chemicals are being identified to
alify for the spill reportabilrty exemptionprovided under 40 CFR 117 and CERCLA.
So'ill Prevention
BC'has one large aboveground oil storage tank (260;000 gals). A concrete dike designed to
contain the entire contents of the tank in the event of an accidental rupture surrounds this tank.
All oil storage facilities are covered under the BC Spill Prevention Control and Countermeasure
Plan.
Hazardous and Toxic Substances Table 2c-3:
At Belews Creek Steam Station, the potential for toxic, and hazardous substances being
discharged is very low. In reference to Item V -D of Form 2 -C, the substances identified under
Table 2c -3 that'may, begin the discharge are A& follows:
Acetaldehyde,,Asbestos, Benzoyl Chlonde; Butyl,Acetate, Cresol, C.yclohexane, Cyclohexanone,
Epichlorohydnn, Formaldehyde, Furfural, Monoethyamine, Naphthemc Acid, Pyeduins,
Stryrene, Triethanolamine, Vanadium, Vinyl acetate, Xylene, and Zircommum and also during
,the course of the year °products such as commercial cleaners and laboratory reagents may be
purchased which contain very low level's of a,substance found in Table'2c -3. It is not anticipated
that these products will impact the ash basin's capacity to comply, with its toxicity, limits, since
their concentrations are extremely low
9

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
40 CFR 117 and CERCI,A Hazardous Substances:
The table below identifies hazardous substances located on -site °that maybe released to the ash
basin during a spill in quantities equal to or greater,than the reportable quantity (RQ) levels as
referenced in 40 CFR 117, 302 and 355. This list is being provided in order to qualify for the
spilLreportability exemption provided under 40 CFR 117 and the Comprehensive Environmental
Response Compensation and Liability Act (CERCLA). These values below represent the
maximum quantities on -site that could be released.at one time and sent tc the ash basin. They do
not reflect quantities that are discharged through typical use.
CHEMICAL AMOUNT (lbs) SOURCE
Ammonia 4,055,000 General Site
Sodium 10 Warehouse
Sodium Hydroxide 25,520 Water Treatment Room
Sulfuric Acid 61,228 Water Treatment Room
Belews Lake Balanced and Indigenous Populations
The attached report entitled, "Assessment of Balanced Indigenous Populations in Belews Lake
Near Belews Creek Steam Station ", indicates balanced and indigenous populations are
recovering Recovery of populations in Belews Lake is associated with a decrease of selenium
bioaccumulation in populations of Belews Lake, following installation of a system to collect and
landfill dry-fly ash in 1984 and reroute of the'ash basin discharge from Belews Lake to the Dan
River in 1985.. The fish eating advisory on Belews Lake was recently revised by the North
Carolina Department of Environment, Health and Natural Resources from all fish species to only
three ,species (common carp, crappie„ and redear sunfish). Duke Power continues to, maintain an
environmental momtonng,program on Belews Lake and the Dan River to assess populations.
Annual summary reports of environmental monitoring of the Dan River per Part III.S of the
present NPDES permit indicates that reroute of the ash basin discharge from Belews Lake to the
Dan River has had no adverse impact on the balanced and indigenous ^populat'ions in the Dan
River.
Duke Power Company's operating expenence- during the past five years under the thermal
limitations imposed,in NPDES Permit No. NC #0024406 ,substantiates, for Belews Creek Steam
Station that`the "thermal component of the'discharge assures the protection and propagation of
shellfish, fish and wildlife in and,on the receiving body of water."
10

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
2.2.14.3 Synthetic Fuel Facility
A coal processing facility is located at Belews Creek that produces synthetic fuel (synfuel). Coal
is conveyed from the Belews Creek coal yard to'the,synfuel plant. 'The synthetic coal product.is
,made by applying a latex -based binder (Nalcoa17890) to the coal at a rate of 0.25% by weight of
coal., The coal is then made into briquettes and transferred to the Belews Creek synfuel storage
pile. The,,mixing,and briquetters are done inside the,synfuel buildings: The synfuel has been
permitted by the Air Quality Division as equivalent to coal. The runoff from the synf iel storage
pile'is routed to the ash basin. The station contract with the coal processing facility expires in.
2007.
Ash Basin Capacity
Part III Section R of the existing NPDES permit for BC requires the permittee to provide and
maintain at all times a minimum free water volume�(between the top of the sediment level and
the minimum discharge elevation) equivalent -to the sum of the maximum 24 hour plant
discharges' plus' all direct rainfall and all runoff flows to the-pond resulting from a 10 year, 24
hour rainfall event, when using a runoff coefficient of 1.0.
BELEWS CREEKSTEAM STATION
Ash Basin Free Water Volume
Determination of Free Water Volume Free Water Volume is the sum of`the runoff accumulated in the ash basin
which results °from a 10 -yr 24 -hr storm (must assume 100% runoff) + the maximum 24 -hr dry weather waste -
stream which discharges to the,Ash Basin (refer to NPDES permit NC0024406, Part I, Section 5)
I.
II.
Estimate Runoff to Ash Basin from 10 -,yr 24 -hr Storm:
1 Natural Drainage Area of Ash Basin =
Station Yard Area Pumped to Ash Basin =
Total =
2 Precipitation from 1,0- yr`24 -hr storm =
3 FGD System Sumps,SMP- 42500A, - 42400A,
and - 42450A Discharge to Ash'Basin
(2,100 gpm capacity for 24 hrs) _
4 Total Stormwater Runoff to Ash Basin =
Estimate Maximum 24 -hr Dry Weather WasWStream Discharging to Ash Basin:
From station records, maximum recorded
Ash Basin discharge (measured weekly) _
11
655 0 Acres
876
7426 Acres
51 inches
93 Ac -ft
324 89, Ac -ft
x1,0 ^6 gallons /
17 90 day

2 For conservatism, increase maximum
discharge recorded at station by 10%
III. Free Water Volume = Sum of (I.) and (II.) above =
Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
6043 Ac -ft
385:32 Ac -ft
IV. Estimate Quantity of Solids (Bottom Ash), Discharged to; Ash Basin From Time of Most Recent
Physical Survey (07/16/04) to Time Permit Expires T(02/28/2012):
Note Estimates from July 2004 through June 2006 are based on historical data, estimates from July
2006 through February 2012 are based on projected data (1st -Qtr 2006 PROSYM Model)
fv
VI.
Time Period
Estimated
Total Ash
Production
000's tons
Estimated
Bottorri.Ash
Production
000's tons
Estimated
Bottom Ash
Utilization
000's tons
Estimated
Btm Ash
to Basin
000's tons
Estimated
Btm Ash
to Basin
Ac -ft
Jul tfiru Dec 2004
3568
393
44
349
291
2005
6852
754
18.5
569
475
Jan,thru Jun 2006
3358
369
11 2
257
21.5
Jul thru Dec,2006
3770
41 5
8,8
327
273
2007
671 9
739
200
539
450
2008
6458
71 0
200
51, 0
426
2009
6272
690
200
490
409
2010
6579
724
200
'52 4
437
2011
618.5
680
200
480
40'1
Jan thru Feb
2012
1179
130
33
96
80
Total
5,094 -1
5603
1462
4142
3458
Estimate Total Storage Volume Required for Term of Permit =)Sum of (III,) and (IV.) above:
Free'Water Volume =' 3853 Ac -ft
Estimated Solids to Ash Basin = 3458
Total = 1 731.1 Ac -ft
Results (use most recent survey date of 07/16/2004 as a reference):
1 At Ash Basin operating elevation 750.0 ft, water volume in the ash basin= 3,406 acre -ft
2, 3,406 acre -ft > 731 acre -ft OK
12

Belews Creek Steam Station, Stokes County
NPDES Permit 9NCO022406
3.0 STI'E STORM WATER RUNOFF ASSESSMENT
3.1 Site Description
Belews Creek Steam Station is a fossil - fueled, electric generation plant located approximately six
miles east of Walnut Cove in Stokes County, North Carolina. The plant began operation in 1974
and has two production units with a net generating capacity of 2,200 megawatts.
The station and its supporting facilities cover approximately 700 acres. The powerhouse yard
includes approximately 30 acres, and the switchyard covers about five acres The coal storage
yard encompasses approximately 50 acres, but the coal pile currently covers only about 15 acres.
There are several scrapyards andmiscellaneous outdoor storage areas at Belews Creek Steam
Station. There are approximately three miles of rail, access and two,miles of paved roadways on-
site. The ash settling basin has a surface area of approximately 325 acres; and runoff from an
additional,325 acres, can drain into the basin. A discharge tower regulates outflow from the ash
settling basin to a tributary of Dan River.
The Flue Gas Desulfirization (FGD) system is currently under construction. Once construction is
completed, the FGD system and components will change many of the run -off characteristics of
the, station site. Primarily, a portion of the rainfall run -off that is ,going directly into Belews Lake
will be collected and sent to the ash basin via a consolidated sump system.
Soils at Belews, Creek Steam, Station are typical of the area except that the region's characteristic
surface clays are not prominent on -site. _Soils are primarily micaceous sandy silts and silty sands
with some clayey sands in flatter areas. The,site topography is generally flat with rolling hills in
outlying, undeveloped areas
In developed - areas, runoff flows overland to ditches and catch basins which -are connected to a
buried network of corrugated metal pipes (CMP). Rainfall' runoff from coal handling areas and
portions of the coal pile is routed to the coal yard holding sumps. Rainfall runoff from western
portions of the coal pile and from the area around the new ash storage dome is routed directly to
the�ash basin. Runoff from the north side of the plant yard is routed to the,powerhouse yard
holding sump Runoff from the area beneath the coal conveyor is routed to a small sump on the
west side of the powerhouse. Effluent. from all sumps is -pumped to the ash settling basin. Storm
water from the remainder of 'the plant yard is routed to several primary trunk lines which
discharge to Belews Lake. Three storm, water outfalls have oil trap tanks to contain potential oil
spills.
There are 18 stornivater,dmscharges and four NPDES discharges at Belews Creek Steam, Station.
Representative sampling is collected at stormwater outfalls 6 and 15. The storm water discharges
are,described in Section 3.2.
13

Belews Creek Steam Station, Stokes County
NPDESPermit #NC0022406
12 Facility Drainage and Inventory of Significant Materials and Controls
Storm_Water.
Non -point sources of storm water to the yard drainage system is based on forty inches of rain per
year with fifty percent run -off, and the yard watershed.area, the yearly average rainfall run-off to
Belews Lake is 0 08 mgd.
BC has several storm water outfalls that discharge to the Dan River or Belews Lake. BC was
included in the group applicatibn submitted to the Environmental Protection Agency in March
1991
This section details eighteen storm water outfalls to Belews Lake. These locations are identified
in the attached site drawing. To provide a complete,description of the storm water drainage
system,, the yard sump systems are also characterized. Additional outfalls have been excluded
because, either they`have been abandoned or because they are not located within the vicinity of
the station or any industrial activity.
A description of the drainage area, ,significant materials, and material control measures is
presented for each drainage basin. In addition to the significant matenals particular to each
drainage basin, herbicides are applied to selected areas throughout Belews Creek Steam Station
to eliminate undesirable vegetation along railways, ash pipelines, and the perimeter fence.
Herbicides are also applied, as needed, `m the gravel' parking lots, switchyard, and laydown areas.
Herbicides are sprayed around the yard sumps, transformers, trailers, and the intake structure.
All herbicides used at Belews Creek 'Steam Station are approved by the company as
environmentally safe and, are applied in an environmentally safe manner and quantity. Records
are retained at the site to document information such as- the areas treated, the herbicide used and,
the - amounts of herbicide used.
• OutfallI
Discharge Structure: 24 inch ( ") diameter O CMP
Location: East of guard house along plant access road, into Belews Lake
Drainage Area- 2.4 acres
Area Description
The station guard house and water tower are located within this drainage basin. Approximately
20 percent of the drainage area is paved or roofed. To the west, a,railway embankment is sloped
at a ratio of two horizontal to one vertical (2H:1 V). The railway embankment covers
approximately 30 percent of the drainage area. A concrete `trench containing°the ash - sluice
pipelines forms the southern border of this drainage basin. Any ash spillage resulting from
rupture of `the pipeline would be, contained within -the trench. Chemical waste from boiler
cleaning activities are piped to the chemical pond through these pipelines.
14

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Significant Materials LControls
Significant materials are not stored within this drainage area.
• Outfa112
Discharge Structure
Location:
Drainage Area:
36" � CMP
Intake Canal
6:0 acres
Area Description
This drainage area includes the smokestacks and the northern portion of the plant yard.
Approximately 35 percent of this drainage area is paved or roofed. Approximately 400 feet of
railway lines pass through this drainage area. Scrap metal and materials', are temporarily stored in
a 1/3 acre lay -down area, east of the $oral (ash management contractor) trailers, and there is a
small parking area beside the trailers. An embankment along the northern basin boundary is
sloped at a ratio of 2H• 1 V and covers, approximately 1.6 acres: At the base of the embankment,
the fuel oil unloading area covers about 7,350 ft2. The ash - sluice pipeline trench borders a
portion of this drainage area; again, spills would`be contained within the trench.
Raw lake water is used to cool the bearings of the induced draft fans, and the once through, non -
contact cooling water is discharged through this outfall. Chemicals are not added to the cooling
water. There is a 10,000 gallon,.steel ammonia tank located in this area, but it is not a risk to
storm water because if the tank ruptured, the product would evaporate.
Sigmficant Materials /Controls
Ash: Flyash is hauled by truck and sometimes, but.rarely, by rail through this area.
• Outfa113
Discharge Structure:
Location:
Drainage Area-
21" � CMP
Intake Canal
1.7 acres
Area Description
The powerhouse roof covers approximately 6:9 ,acres within this drainage basin. This drainage,
area contains approximately 180 feet of paved roadway and 360 feet of rail lines. About 60
percent of the drainage area is surfaced or roofed.
Significant Materials / Controls
Ash: Flyash is sometimes, but rarely, transported by rail through this area.
15

• Outfall4
Discharge Structure:
Location:
Drainage Area-
18" � CMP
Intake Canal
1.1 acres
Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Area Description
The powerhouse roof and the roofs of the nitrogen and hydrogen ,gas storage houses cover
approximately 0.55 acres in this drainage basin. This drainage area contains approximately 140
feet of paved roadway and 200 feet of rail lines Approximately 50 percent of the drainage area
is surfaced or roofed.
Significant Materials / Controls
Ash- Flyash is sometimes, but rarely, transported by rail through this area.
• Outfa115
Discharge Structure:
Location.
Drainage Area-
15" � CMP
Intake Canal
1.3, acres
Area Description
This drainage basin contains approximately 0.4 acres of the gravel covered yard area in front of
the old warehouse. Trailers located within the gravel area have roof area of approximately 31,450
square feet. Vehicles park7around the trailers. `This dramage'area contains approximately 380
feet of paved roadways and approximately 290 feet of railways. Approximately 20 percent of
this drainage basin is paved or roofed, not considering the gravel area.
Significant Materials / Control's
Ash: Flyash is sometimes, but rarely, transported by rail through this area.
Oil- A transformer beside the eastern gas storage house,contains 196 gallons of oil.
16

Belews Creek�Steam Station, Stokes County
NPDES Permit #NC0022406
Outfa116
Discharge Structure: 18" � CMP
Location. Intake Canal
Drainage Area: 16 acres
Area Description
Most of this area is, currently,under construction for the FGD project.
Significant Materials / Controls
Significant materials are not stored within°this drainage area that will drain directly into Belews
Lake
• Outfa117
Discharge Structure: 24" � CMP
Location: South East of Station
Drainage Area: 12.0 acres
Area Description
Most of this area,is currently under construction for the FGD project.
Significant Materials / Controls
Sigmficant.matenals are not stored within this drainage area that will drain into Belews Lake.
• Outfa118
Discharge Structure 12" � polyethylene
Location: Discharge Canal
DrainageArea: �0.9 acres
Area Description
This out-fall conveys storm water runoff from a small, wooded area.
Significant Materials / Controls
Significant materials areinot stored within this drainage area.
17

Outfall 9
Discharge Structure:
Location
Drainage Area:
24" � CMP
Discharge Canal
27 acres
Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Area Description
Most of this drainage basin (25.3 acres) is an undeveloped, wooded area. The ditch along the
southeast of the power station. Less than one percent of this area is paved.
Significant Materials / Controls
This drainage area is currently being modified due to the FGD system. Run -off from areas that
have significant material will be re- routed to ,the ash basin.
• Outfa1110
Discharge Structure:
Location-
Drainage Area:
36" � CMP
Discharge Canal
1.7 acres
Area Description
Most of this area is currently under construction for the FGD project.
Significant Materials / Controls
This drainage area fs currently being modified due to the FGD system. Run -off from areas that
have significant material will be re- routed to the ash basin.
• OutfallII
Discharge Structure-
Location.,
Drainage Area:
15" � CMP
Discharge Canal
0 7 acres
Area Description
This drainage basin is covered with gravel and grass and located south of the Unit 2 transformers.
There are about 280 feet of paved roadways and almost 400 feet of railways within this area.
Approximately 20 percent of this drainage basin is paved.
Significant Materials,/ Controls
Ash: Flyash is sometimes, but:rarely, transported by rail, through this area.

Y Outfall12
Discharge Structure:
Control Structure:
Location:
12" � CMP
2,500 gallon oil trap tank
Discharge Canal
Belews Creek Steam Station, Stokes County -
NPDES Permit #NC0022406
Drainage Area: 0:2 acres
Area Description
This drainage basin contains the Unit 2 transformer yard. The entire area is covered with gravel.
All,runoff from this area is routed to a 2,500 gallon oil -trap tank before being discharged to
Belews Lake.
Significant Materials / Controls
Oit: The, Unit, 2 transformers contain a total of 43,738 gallons of mineral oil. Transformers 2A
and 2B each contain 13,569 gallons of oil, and CTII contains 16,600 gallons of oil. A six -
inch high concrete curb surrounds the transformer'yard. Catch basins and cable trenches
within this area are,routed to a 2,500 gallon oil trap tank.
® Outfa1113
Discharge Structure,
Control Structure:
Location-,
Drainage Area:
21" � CMP
1,000 gallon oil trap tank
Discharge Canal
2.0 acres
Area Description
This drainage basin is covered in gravel and grass and located south of the Unit 1 transformers
A portion of 'the powerhouse roof covers approximately one �acre of this drainage basin. The area
has approximately 230 feet of paved roadway and 400 feet of-railways. Approximately 55
percent of thiss drainage area is paved or roofed. All runoff from this area is routed to a 1,000
gallon,oil trap tank.
Significant Materials / Controls ,
Oil: Drains inside, some ,cable trenches within the transformer, yard are routed through the 1,000
gallon oil trap tank to this outfall. The transformers contain a total of 85,206 gallons of
mineral oil. A six -inch high concrete curb surrounds the transformer yard. Catch basins
within the transformer yard are,routed to two other 2,500,gallon oil trap tanks.
Ash. 'Flyash is sometimes, but rarely, transported by rail through this area.
19

0 Outfa1114
Discharge Structure:
Control Structure:
Location;
Drainage Area:
12" � CMP
2,500 gallon oil trap tank
Discharge Canal
0.2 acres
Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Area Descnption,
This drainage basin contains the Unit 1 transformer yard. The entire area is covered with,gravel.
All runoff from this area is, routed to, a 2,500 gallon oil -trap tank before being discharged to
Belews Lake.
Significant Materials / Controls
Oil: The Unit 1 transformers contain a total of 41,468 gallons of mineral oil. Transformers I
and 1B each contain 12,400 gallons of oil, and CTI contains 16,66$ gallons of oil. A six -
inch high concrete curb surrounds the transformer yard. Catch basins within this area are
routed,to a 2,500 gallon oil trap tank.
• , Outfall 15
Discharge Structure: 42" ifi CMP
Location: Discharge Canal
Drainage Area: 14:3 acres
Area Descnption
This drainage area covers the western portion of the powerhouse yard. The, ash - sluice pipeline
trench forms the northern boundary of this drainage area; spills would be contained within the
trench. The embankment leading to the coal pile is sloped at a ratio of 2:1 H:V and covers about
2.3 acres There are approximately 0:5 miles of paved roadways ,and about 800 feet of railways.
The powerhouse and service' building roofs cover approximately 3 6 acres. Paved parking areas
cover about 1.5 acres Approximately 50 percent of this drainage basin is paved or roofed. An
oil skimmer is permanently in place around this outfall in the discharge canal
Some floor drains within, the service building are connected to this outfall. Air conditioning
condensate and a water fountain drain to a floor dram,m the shop area.
Significant Materials / Controls
Oil: A spare transformer contains 13,300, gallons of mineral, oil. This area is inspected daily for
oil spillage /leakage.
20

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
The used oil storage tank is 'made of carbon steel and has a capacity of 4,000 gallons. It is
surrounded by a concrete berm, two feet- in height, which could contain a total tank spill
plus rainfall. A valve that allows rainfall to drain into the hazardous waste storage area is
kept closed.
Used oil and oily waste are stored in 55- gallon drums on a concrete pad 85 feet long and 30
feet wide. A concrete curb about six inches in height surrounds the pad. There is a sump
within the pad to drain accumulated rainfall. The sump has a valve which is kept closed
and locked Any rainfall is� inspected for oily sheen, and if a sheen is present, oil absorbent
pads are used.
Universal / Hazardous Waste: Hazardous waste is stored on pallets on a concrete pad beside the
used oil tank. The pad is surrounded by an eight -inch concrete curb. A fire extinguisher is
stored within this area. There is a sump within this area to drain accumulated rainfall. The
sump has a valve which is kept closed.
Used batteries are ,stored on pallets on a concrete pad beside the hazardous waste storage
area. The -pad is surrounded by an eight -inch concrete curb.
Used anti=freeze is stored in a 55- gallon drum on the used oil pad. A concrete curb about
six inches in height surrounds the pad.
Gasoline: A 2,500 gallon underground gasoline storage tank is located south of the servibe-
building. It is filled by an 8,0`00 gallon tanker truck. Adjacent to the tank is a fuel
dispenser,. A small sump around the dispenser drains to this outfall.
Ash: Flyash is sometimes, but rarely, transported by rail "through this area
Storage: Scrap metal, wood, wire, and materials are stored in an outdoor laydown area.
• Outfall16
Discharge Structure: 30" � CMP
Location: Switchyard into Discharge Canal
Drainage Area: 5.6 acres
Area Description
Approximately two acres tof the, switchyard are included within this drainage area. The
switchyard is covered with gravel. There are approximately 250 feet of paved roadways, 250 feet
of railways, and 2,400 square feet of roofed area within this drainage basin. The railroad
embankment is sloped 2H• 1 V and covers approximately 0.4 acres. A laydown area covers about
0.5 acres.
21

Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Significant Materials / Controls
Oil: There area total of 23 circuit breakers in the switchyard, and each one contains 10 gallons
of hydraulic oil.
Storage- Scrap metal and other materials are stored in an outdoor laydown area.
Ash: Flyash is sometimes, but rarely, transported by rail through this area.
• Outfa1117
Discharge Structure: 30" � CMP
Location: Switchyard into Discharge Canal
Drainage Area. 5,.9 acres,
Area Description
Approximately 1.5 acres of the switchyard are included in this drainage area. The switchyard is
covered, with gravel. There are approximately 360 feet of railways within this drainage basin.
The railroad embankment is sloped 2HJ V and covers approximately 0.7 acres. A_ laydown area
covers about 0 3 acres.
Significant Materials / Controls
Oil. There area total of 23 circuit breakers, in the switchyard, and each one contains 10 gallons
of hydraulic oil.
Storage: Scrap metal and materials are stored in an outdoor laydown area.
Ash: Flyash is sometimes, but,rarely, transported by rail through'this area.
• Outfa1118
Discharge Structure: 24" � CMP
Location:, South of switchyard, ,overland to Belews Lake
Drainage Area 9.8 acres
Area Description
This drainage basin consists primarily of undeveloped areas to the west and south of the tractor
maintenance shed. There are approximately,900 feet of, "railways within this drainage basin.
Runoff from this drainage basin accumulates in a small detention pond where there is a riser
standpipe discharge structure approximately two feet in height. The detention pond,allows
sediment to settle out of the runoff, and the riser limits, storm water conveyance through this
outfall Discharge from this outfall occurs only during significant rainfall events. Overflow from
the south coal yard sump can reach this outfall.
22

Belews Creek Steam Station, Stokes County
NPDES Permit #N00022406
Significant Materials / Controls
Ash: Flyash is sometimes, but rarely, transported by rail through this area.
Yard Sump Systems
There are four holding sumps at Belews Creek Steam Station: two coal yard holding sumps, a
small holding sump'beneath the coal conveyor, and a plant yard holding sump. Effluent from all'
holding sumps is routed to -the ash basin.
• North Coal Yard Sump
The north coal yard sump 'is located at the north end of the coal pile, and it collects runoff from
an area of about 4.8 acres. Drainage is collected from portions of the coal'pile and coal handling
areas. The roofs of the coal handling facilities cover approkimately 2,400 ft2. Approximately
0.25 miles of railways pass through the area. Approximately one percent of this drainage area is
roofed The trench containing the ash sluice pipelines passes through this area; spills would be
contained within the trench.
Significant Materials / Controls
Oil. A tractor and a bulldozer refueling station are located within this drainage area. The power
pack at the transfer tower contains approximately 55 gallons of hydraulic fluid.
Coal: Runoff from portions of the coal pile and coal handling areas flows to this holding sump.
• South Coal Yard Sump
The south coal yard sump is, located at the south end of the coal pile, and it collects runoff from
an area of about 13 acres. Drainage is collected from portions of the coal pile and coal handling
areas. The roofs of the coal handling, facilities and tractor maintenance shed, cover approximately
18,50.0 ft2. The concrete paved area around the tractor shed covers about 8,000 ft2. The concrete
area is surrounded by a 6 -inch curb and is sloped to drain to a ,small sump 'that goes to. the south
coal yard sump Approximately 1.5 miles of railways and about 0 2 miles of roadways pass
through the area Approximately, five percent of this drainage area is roofed or paved.
Significant Materials / Controls
Oil: The reduction, gearboxes for coal conveyors 1 -3 containa total,of approximately 150
gallons of oil. Oil spills from conveyor systems 4 and 5 would be contained within a tunnel
or would go to the powerhouse.
23

f
4
Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
Floor trenches inside the tractor maintenance shed' dram ,to the south sump. Locomotive
and bulldozer maintenance is performed inside the tractor shed. A 500- gallon tank of
transmission fluid is stored inside the tractor maintenance shed. A concrete berm
approximately two and one half feet high surrounds the tank. Approximately 500 gallons
of torque fluid and 500 gallons of engine hydraulic oil are stored in tanks inside the tractor
shed: These tanks are surrounded by a three -foot high concrete berm. Used oil and oily
waste are stored in 55- gallon drums inside, and outside,the tractor shed.
Universal Waste: A 55 gallon drum is used to temporarily store anti - freeze in a satellite
accumulation area inside the tractor shed.
Coal: Runoff from,portions of the coal pile and coal handling areas flows to this holding sump.
• Coal Conveyor Sump
The coal conveyor sump is located beneath the coal conveyor, to the west of service building.
This sump captures coal particles that fall from the conveyor as well as the wash water from
when the conveyor belt is rinsed. Runoff from an embankment adjacent to the coal unloading
house is routed to this sump. This drainage basin covers approximately one acre.
Significant Materials / Controls
Coal: Coal and wash water that falls from the overhead conveyor.
Chemicals- A 1,000 gallon tank,of dedustmg solution is located behind the coal conveyor.
® Consolidated Yard Sump
A ,yard sump was installed as part of the FGD and ash landfill projects. This .sump collects
rainfall run -off from the material handling areas, the gypsum landfill and the ash landfill. This
sump also collects treated wastewater from the sanitary lagoon system.
24

•
4
Belews Creek Steam Station, Stokes County
NPDES Permit #NC0022406
• Plant Yard Folding Sump / Ash Pipeline Trench
The plant yard holdmg;sump is located north of the powerhouse Inflow'to the plant yard•holdmg
sump comes from powerhouse equipment effluent and from storm water runoff from the plant
yard area north of the powerhouse. `This portion of the plant yard contains the precipitators, the
ash silos, and the ash sluice trench. The plant yard in this area is paved and sloped to drain to the
ash trench. Drainage from approximately 27,500 square feet of the powerhouse roof is routed to
the yard holding sump. From inside, the powerhouse, discharge from the turbine room sumps,
boiler room ,sumps, and floor drains is routed to the yard holding sump This drainage area
contains -3.8, acres, and ,approximately 95 percent of the area is paved or roofed.
There is a 10,000 gallon steel ammonia tank located in this area, but it is not a risk to storm water
because if the tank ruptured, the product would evaporate. There is also a steel tank containing
molten sulfur, but it is not a risk to storm water because the sulfur•would solidify if the tank.
ruptured.
Significant Materials / Controls
Oil- The transformers atop, the precipitators contain a total of 11,200 gallons of oil. The
maximum�reservoir "size `many one transformer is 205 gallons.
Chemicals: The sulfuric and caustic acid unloading area is located at the north face of the
powerhouse. Department of Transportation (DOT) procedures are followed during
unloading. Occasionally, chemical wastes that result from plant cleaning projects are, sent
to the ash basin via the ash pipelines.
Ash: Waste ash is sluiced through this area, in route to the ash, basin. The ash pipelines are
contained in a concrete trench.
Flyash is transferred from the plant to the ash -silos through above ,grade pipelines. The ash
is transferred from the ash silos to trucks for transport to either off -site facilities or on -site
storage /disposal.
Wastewater: Plant wastewater from equipment discharges, floor drains, sumps, etc. is routed to
the plant yard holding sump. This wastewater may include oil, chemical, and hazardous
waste spills
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