NC0024406_Renewal Application_19910705

BELEWS CREEK STEAM STATION
EPA ID# NC0024406
NPDES PERMIT RENEWAL APPLICATION
Supplement Information Document
for EPA Form 2C
Document Written: 3/89
Document Revised: 6/91

A schematic flow diagram of water use, treatment provided, recycle accomp-
lished, and discharges indicating rates of flow for individual wastes streams
is attached. A brief discussion of the individual waste streams follows:
Boiler Condensate Polishing: Belews Creek Steam Station operates super-
critical ._pressure boilers with continuous flow-through of boiler feed
water. Blowdown is not used. The cleanup function that blowdown
provides for subcritical drum -type boilers is replaced in the
supercritical cycle with condensate polishing demineralizers of the
powdered resin type.. The mixed anion -cation powdered resin provides
filtering and ion exchange to replace the boiler blowdown sequence.
Spent resins and associated wastes are pumped to the ash basin for
treatment and disposal.
Floor Drains: The wastes which enter the floor drains accumulate in the
power house sumps. The wastes originate from such sources as (1) water
treatment equipment (2) floor wash water, (3) equipment cooling water and
(4) miscellaneous leaks. All effluents from the floor drains are
discharged to the yard holding sump and then pumped to the ash basin.
Chemical Cleaning of Boilers and Filters
A. The two supercritical boilers are each cleaned every two years. 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. A list of
the chemicals and approximate amounts for one boiler cleaning is as
follows:
Chemicals Amount
1.
Hydroxyacetic Acid
22,400
lbs.
2.
Formic Acid
11,200
lbs.
3.
Ammonium Bifluoride
2,800
lbs.
4.
Ammonium Hydroxide (260Be)
1,875
lbs.
5.
Hydrazine (54.4%)
1,320
lbs.
6.
Corrosion Inhibitor (Proprietary)
500
lbs.
B. The two auxiliary boilers "A" and "B" are cleaned with an alkaline
boilout. These cleanings are not performed routinely and are done
on an infrequent basis. The alkaline cleaning wastes are pumped to
the ash basin. A list of the chemicals and approximate quantities
for one auxiliary boiler alkaline boilout is listed below:
Chemicals Amount
1. Soda Ash 300 lbs.
2. Triton X-100 Detergent 2 gallons
3. M45 Antifoam Agent 1z gallons
C. The condensate polisher filters and filtered water system filters
are cleaned with citric acid on an annual basis. The citric acid is
mixed to a 3% solution and the solution is discharged to the ash
BC - Page 2
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basin once the cleaning has been accomplished. The chemical and
quantity used per year for this cleaninc is listed below:
Chemical Amount
_Citric Acid 1,200 lbs.
4. Coal Pile Drainage
The coal yard covers approximately 51.5 acre_. The average rainfall
run-off is 0.08 MGD. This runoff is based or. 40 inches of rain per year
with 50/. runoff.
Most of the coal yard drains naturally into the ash basin near the point
of ash influent. The remaining drainage frog the coal yard flows to the
coal yard sumps where it is then pumped to tFe ash basin.
5. Ash Basin Overflow
The ash basin accommodates flows for the coal yard, ash removal lines,
the chemical holding pond, the yard holding sump and rainfall run-off
from the ash basin's watershed area.
The yearly average rainfall runoff for the ash basin's watershed area is
0.47 MGD. This flow is based on forty inches of rain per year with fifty
percent runoff. The ash basin effluent flowrate in 1987 averaged 7.7
MGD.
The chemical nature of the wastes entering the ash basin is utilized to
improve treatment. The basin's long retention time also helps to improve
the mechanisms of neutralization, coprecipitation, precipitation, oxida-
tion and ion exchange of the influent waste s_reams. Floating solids
within the ash basin are retained by an under over collar attached to the
discharge tower.
6. Oil Storage Run -Off
Belews Creek Steam Station has one large above ground oil'storage tank
(260,000 gals). This tank is surrounded by a dirt dike designed to
contain the entire contents of the tank in the event of an accidental
rupture.
All oil storage facilities are covered under :he Spill Prevention Control
and Countermeasure Plan.
7. Intake Screen Backwash
The intake screens are backwashed as required at the rate of 500 GPM for
approximately 5 minutes each. With 8 (4 per unit) screens, the total
volume of water used is .02 MGD. The screens (18' x 23') are stationary
and are removed for cleaning. The debris remcved from the screens is
collected within a cleaning basin. The clean water is returned to the
intake canal. The collected debris is removed to the ash basin area for
burial.
BC - Page 3
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8. Water Treatment Equipment Waste
The water treatment equipment consists of one (1) retention tank, two (2)
pressure filters (diatomaceous earth)., two (2) activated carbon filters,
and one (1) set of make up demineralizers. The pressure filters each
have a ca-pacity of 500 GPM. Filters are backwashed weekly with
approximately 200 lbs. of diatomaceous earth going to the ash basin.
Make up demineralizers are operated in sequence (1 cell at a time).
Regeneration of these cells is required approximately every other day. A
regeneration requires 60 gallons of 66°Be sulfuric acid and 300 gallons
of 50% sodium hydroxide. An average dilute waste chemical and rinse flow
of 0.17 MGD is realized (for 1 hr/regeneration). The diluted acid and
caustic are discharged to the yard holding sump and then pumped to the
ash basin.
9. Effluents from Air Pollution Control Devices
Electrostatic precipitators are used to remove fly ash from the stack
gases. The ash is treated in the flue gas ductwork with SO, conditioning
to improve removal efficiency. Typically, ash is removed in a dry form
and -disposed in an on-site landfill. In the case of equipment failure or
immediately following an outage, service water is used to sluice the ash
to -the ash basin.
10. Sanitary Wastes
Sanitary wastes are treated in a tertiary treatment system which consists
of a two cell aerated lagoon, a dosing tank, a sand filter, and a Sanuril
chlorinator. Based on yearly data, the average daily flow is -3000 GPD.
11. Condenser Cooling Water
This condensers are cleaned by a mechanical system, trade name "Amertap".
This system circulates small sponge rubber balls through the condenser
tubes.
Each unit has four condenser cooling water (CCW) pumps. The operational
schedule for CCW pumps is a function of the intake water temperature and
the unit load. The following table outlines the different operating
conditions.
Unit #1 or #2
Number of Pumps
1
2
3
4
Total Flow (qpm)
184,000
333,000
444,000
506,000
Intake Temp (°F)
<61
61-69
>69
One pump operation is normally utilized when a unit is off line to aid in
the unit's start up. Usually at 100% load four pumps are used.
„ a BC = Page 4
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BC - Page 5

LEGEND
Plant Belews Creek Schematic
Flow Stream Avg. Daily Flow. MGD*
I.
Ash Basin Rainfall Runoff
0.47
2.
Coal Yard Rainfall Runoff
0.08
3.
Yard Drainage to Intake Canal
0.03
4.
Yard Drainage to Discharge Canal
0.05
A.
Intake Water
1088.5
B.
RCW Cooling Water
50.20
C.
Condenser Cooling Water
1023.847
D.
High and Low Pressure Service Water
14.403
E.
Intake Screen Backwash
.0.02
F.
Miscellaneous Plant uses including Washdown
and Fire Protection
1.073
G.
Water Treatment System
0.38
H.
Coal Handling System
0.45
I.
Service Water Discharge to Ash Removal
2.75
J.
Water Treatment System to Miscellaneous
Equipment and Seals
0.09
K.
I.D. Cooling Water
0.35
L.
Hydrogen and Oil coolers
5.58
M.
Plant air conditioning
1.30
N.
Water Treatment System Wastes
0.087
0.
Condensate Feedwater System Effluent
0,2
P.
Continuous - Ash Hopper Seals and Cooling
2.50
Q.
Sanitary System Influent
0.003
R.
Condensate Feedwater System
0'.10
S.
Power House Sumps Effluent
3.85
T.
Evaporative Losses, Soot Blowing
0.10
U.
Boiler Cleaning Wastes
0.003
V.
Fly and Bottom Ash Sluicing
2.75
W.
Yard Holding Sump Effluent
3.85
X.
Turbine and Boiler Room Drains
1.163
001
Condenser and Miscellaneous Equipment
003
Noncontact Cooling Water
Ash Basin Discharge
1079.677
002
Sanitary System
7.6
0.003
*Flows are extrapolated beyond the scope of significant figures in this table
and throughout this narrative to account for variations in flow capacities.
BC - Page 6.

PART D
The following tabulation lists the hazardous substances located on site in
accordance with 4.0 C.F.R. 117.12 and the legislative regulatory history to
qualify for a §311 exclusion under the Clean Water Act.
BC - Page 7

Belews Creek
List of Hazardous Substances (Section 311)
Pollutant
Acetic acid -
Ammonia
Ammonium hydroxide
Calcium hypochlorite
Chlorine
Chloroform
Cupric chloride
Cupric nitrate
Cupric sulfate
EDTA
Ferrous chloride
Ferrous sulfate
Formaldehyde (34%)
Hydrazine** (54.4%)
Hydrochloric acid
Hydroflouric acid
Nitric acid
Phosphoric acid
Potassium hydroxide
Potassium permanganate
Silver nitrate
Sodium bisulfite
Sodium hydroxide (50%)
Sulfuric acid
Quantity
Source
3 qts.
Lab
1 lb.
Lab
2000 lbs.
Boiler Chemical
100 lbs.
Water Treatment
600 lbs.
Water Treatment
8 pts.
Lab
1 lb.
Lab
1 lb.
Lab
1 lb.
Lab
1 lb.
Lab
1 lb.
Lab
1 lb.
Lab.
1 gal.
Lab
220 gals.
Water Treatment
12 gals.
Lab
1 lb.
Lab
2 gals.
Lab
2 gal.
*Lab
3 lbs.
Lab
1 lb.
Lab
4 oz.
Lab
5 lbs.
Lab
7000 gals.
Demineralizer
Regenerate
4503 gals.
Demineralizer
Regenerate
*Values represent maximum quantities stored onsite and do not necessarily
reflect quantities discharged or total annual consumption/use. Treatment of
these and other chemical substances not identified is achieved by the ash
basin. Refer to Item 3 of this document for a list of chemicals and amounts
used for boiler cleaning.
**Hydrazine is not included in the Section 311 hazardous substances.list. It
is included in this table because it is included in the list of hazardous
substances found in 40CFR302.4.
BC - Page 8

EPA ID # NCO024406
�j= Belews Creek Steam Station
Form 2C
Clarifying Notes / Supplemental Information
Section TT
Item II.A.: The line drawing is attached as page 5 of the "Supplemental
Information Document for EPA Form 2C."
Item II.B.:
1. Outfall 006 is a metal cleaning waste holdup, neutralization, and
sedimentation pond. Discharge from the metal cleaning wastes holdup
pond is to the ash basin and is intermittent. The average flow
noted is based on draining the metal cleaning waste pond down to its
lowest pond elevation within a 24 hour period. This flow is the
maximum expected at anytime.
2. Outfall 005 is an infrequent discharge used to augment lake levels
in Belews Lake. Under typical operating conditions the ash basin
will discharge via Outfall 003 to the Dan River.
3. Intake screen backwash, non -contact cooling water, and stormwater
discharges are not listed in Section I because it is -anticipated
that these discharges will be addressed in permit Section III
without limitations or monitoring requirements as is the case in the
current permit.
Item II.C.:
1. Outfall 002 (sanitary wastewater) is an intermittent discharge with
an average discharge volume of 1,800 gallons for a duration of 45
minutes. The long term average is 1.67 discharges/day and the
maximum is 4 discharges/day.
2. As noted in Item II.B.1. above, Outfall 006 (metal cleaning
wastewater holdup pond) is an intermittent discharge. There has not
been a discharge from this point since it was designated as an
outfall -in the most recent permit.
Section IV. B.
The facility currently plans to modify the sanitary wastewater treatment
system. The proposed modification would provide primary treatment with a new
aerated lagoon. Secondary treatment will be provided with a new spray
irrigation system which will include a chlorine contact chamber. This
modification would eliminate the present sanitary wastewater discharge
'(Outfall 002) because the planned modification is a non -discharge type system.
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EPA ID # NC0024406
Belews Creek Steam Station
Form 2C Item VIII
Additional Information Continued from Form 2C, Page 4
Laboratory Pollutants Analyzed (continued)
Compuchem Laboratory Acrolein, Acrylonitrile, Benzene, Bis (Chloromethyl)
Ether, Bromoform, Carbon Tetrachloride,
Chlorobenzene, Chlorodibromo Methane Chloroethane,
2-Chloroethylvinyl Ether, Chloroform,
Dichlorobromomethane, Dichlorodifluoromethane, 1,
1-Dichloroethane, 1, 2-Dichloroethane, 1,
1-Dichloroethylene, 1, 2 Dichloropropane, 1, 3
Dichloropropylene, Ethylbenzene, Methyl Bromide,
Methyl Chloride, Methylene Chloride,
1,2,2 -Tetrachloroethane, Tetrochloroethylene,
Toluene, 1,2 -Trans Dichloroethylene,
1,1,1 -Trichloroethane, 1,1,2 -Trichloroethane,
Trichloroethylene, Trichlorofluoromethane, Vinyl
Chloride, 2 -Chlorophenol, 2,4-Dichlorophenol,
2,4 -Dimethylphenol, 4,6-Dinitro-O-Cresol,
2,4-Dinitrophenol, 2-Nithophenol, 4-Nitrophend,
P-Chloro-M-Crosol, Pentachlorophenol, Phenol,
2,4,6 -Trichlorophenol.
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