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HomeMy WebLinkAboutNC0024392_Revision to WWCB Volume_20170612DUKE ENERGY June 5, 2017 Duke Energy Carolinas LLC McGuire Nuclear Station 12700 Hageis Ferry Road Huntersville, NC 28078 Ms. Teresa Rodriguez RECEIVEDINCDEWWR Division of Water Resources JUN 1 2.2017 WQ Permitting Section — NPDES 1617 Mail Service Center Water Quality Raleigh, NC 27699-1617 Permitting Section Subject: McGuire Nuclear Station Revision to WWCB Volume as provided in NPDES Supplemental Information — NPDES Permit NCO024392 Dear Ms. Rodriguez: As you recently discussed with Melanie Gardner, Duke Energy Environmental Services, the NPDES Supplemental Information for McGuire Nuclear Station's NPDES Permit states that the volume of the Waste Water Collection Basin (WWCB) is 40 million gallons. Recently, station engineering noted and confirmed through a 2013 topological survey that measured actual volume for the WWCB is 22.7 million gallons. Please note this update and contact Macrae Walters by phone at (980) 875-5635 or by email at Macrae.Walters a�Duke-Energy.com or Melanie Gardner at (919) 621-3177 or Melanie. Gardner(cD-Duke-Energy.com if you have any questions or concerns. Sincerely, 460171141 Steven D. Capps Site Vice President Duke Energy Carolinas, LLC McGuire Nuclear Station enc: Updated Supplemental Information for Permit NCO024392 cc: Macrae Walters MG01 EM John Williamson MG03A3 f. RECEIVEDINCDEQ/DWR JUN 12 2017 Water Quality Permitting Section SUPPLEMENTAL INFORMATION FOR MCGUIRE NUCLEAR STATION NPDES PERMIT # NCO0243 92 Revision 7 7/10/2014 For Use With NPDES Permit Effective 6-01-2016 TABLE OF CONTENTS OVERVIEW 4 STATION INTAKE 4 Surface Intalce Subsurface Intake NUCLEAR SERVICE WATER--- ------- --------- --------------- - _ _ _ -----.__----------_----__ -- 5 _ Containment Spray Heat Exchangers CONVENTIONAL LOW PRESSURE SERVICE WATER_ — ____ __--- ---- __ _--- _-6 6 FIRE PROTECTION SYSTEM OUTFALL 001 Condenser Cooling Water -------------------- ---- --- ------------------ - ----- ------------- ---- _ _ — --------------- - ----- ---- --- -- - - Ventilation Unit Condensate Drain Tank _ - _ ----------- (VUCDT) 7 8 —_ 3160_ Study_ and Thermal Variance � OUTFALL 002 Water Treatment Room Sump 9 10 Filtered Water System -... .... Drinking Water System 10 _ Demineralized Water System 10 Turbine BuildingSumpS — - — ------- 10 - - - --- — -- _ - - - - - - --------------— - - Diesel Generator Room Sumps i- - - - - ---- 11 -- - - - -- - - - - -- 1� - Lab Drains - ---- - - -- - -- -- - --- - --- Condensate Polisher Backwash -- - - --- 12 _ 12 ___12_ - - -- - ------------- -------- -- - ---- -- - - - -- - ------ - -- ----- - 13 Steam Generator Blowdown Wet Layup Auxiliary Elect-ic Boiler Blowdown 13 13 Groundwater Drainage S_sy tem RC System Unwaterin Closed Cooling Systems Standby Shutdown Facility 14 Steam Generator Cle4mn9 _ 14 t e Miscellaneous System/ComponenCl ii -n ------- 14 -------------- ------------------ - - 15 - ---- — -- — -- --- Alkaline Boilout Solutions ------------ ----- --- ----- Acid Solutions - - ------------------- -- 15 Acid Solution Additives _ _� �— — _ _ 15 15 -------- -- Compou_ nds and HEDTA _EDTA Miscellaneous Copounds---+ m 15 --------------------------- --- - ----- 16 -- -------------------------------------- Landfill Leachate McGuire Garai4e 16 Page 2 of 24 McGuire Office Complex 16 Nondestructive Examination 17 Ice Condenser 18 OUTFALL 003 OUTFALL 004 Floor Equipment and Laundry Drams 19 Ventilation Unit Drains 19 Chemical Volume and Control System 19 Chemical Treatment in WM S sy tern 19 OUTFALL 005 Standby Nuclear Service Water Pond 20 Administrative BuildingDDiains 20 RG System Unwatering 21 Filtered Water 21 HVAC Urut Drawls 21 Yard Drawls 21 OUTFALL 006 22 APPENDIX 1 Water Use, Diagram 24 Page 3 of 24 OVERVIEW McGuire Nuclear Station is a two unit Auclear steam electric generating station. It is owned and operated by Duke Energy Carolinas LLIC . Each unit has a four loop pressurized water reactor. Reactor fuel consists of uranium oxide pellets clad in zirconium alloy fuel rods. Reactor heat absorbed by the Reactor Coolant System (primary side) is transferred to four steam generators to produce steam (secondary side) sufficient enough to drive a turbine generator with a design net electrical rating of 1180 megawatts. The nuclear reaction is controlled by control rods and chemical neutron absorption. Boric acid is used as a chemical neutron absorber and to provide borated water for emergency safety injection. During reactor operation, changes are made in the reactor coolant boron concentration. A schematic diagram of water use and waste water discharges for McGuire Nuclear Station is attached as Appendix 1. It is possible for any of the discharges to contain low levels of radioactivity. All discharges of radioactivity are regulated by the Nuclear Regulatory Commission in accordance with 10 CFR Part 20 and 10 CFR Part 50. The following is a brief description of the major systems. STATION INTAKE All water for McGuire Nuclear Station 'is withdrawn from Lake Norman through a dual intake system, a surface and a subsurface system. These systems supply the Main Condenser Cooling Water (RC), Conventional Low Pressure Service Water (RL), Nuclear Service Water (RN), Fire Protection System (RF/RY), and Cont i'nment Ventilation Cooling Water System (RV). Surface Intake McGuire Nuclear Station has two power generating units with four Condenser Cooling Water (RC) pumps per unit. There are two intake screens per pump for a total of 16 screens. The intake screens are back washed on an intermittent basis to prevent differential pressure buildup across the intake screens. The frequency of cleaning is determined by the amount of debris on the screens. Approximately 8,500 gallons of water is used to backwash each screen. The water is returned to Lake Norman at the intake bay. The backwash water is raw lake water. No chemicals are used in the backwash water. Subsurface Intake The subsurface intake (Low Level Intak Ford Dam. There are six low-level rntal Currently only 3 pumps are operational. During certain times of the year, this sy (hypolimmon - perpetually colder water warmer water in the surface intake strut temperatures. At all times of the year, t RN Systems. e) is located near the bottom of Lake Norman at Cowans :e pumps with a capacity of 150,000 GPM each. The Unit 2 pumps have been taken out of service. ;tem pumps cooler water from the bottom of the lake in the lower part of the lake) and mixes it with the ture during times of high lake surface water le Low Level Intake (LLI) supplies water to the RV and Page 4 of 24 The LLI lines are periodically drained to the Catawba River just below the Cowan's Ford Dam for inspection. NUCLEAR SERVICE WATER The Nuclear Service Water (RN) System is a safety related, once -through, non -contact Cooling water system The RN System supplies cooling water to various heat loads in both the primary and secondary portions of each unit. There are two pumps per unit (four pumps total) that are capable of delivering 17,500 GPM per pump. The water supply for this system is from Lake Norman or the Standby Nuclear Service Water Pond (SNSWP). Water from Lake Norman is supplied by the RC system from the surface intake or by the Low Level Intake (LLI). The normal source of water is the LLI system. The normal discharge is to Lake Norman through Outfall 001. The SNSWP is a 34.9 acre pond designed to provide cooling water for the safe shutdown of the station in the unlikely event that Lake Norman becomes unavailable. The level in the pond is maintained, per requirements of the McGuire Nuclear Station Technical Specifications, by pumping water from Lake Norman into the pond. The pond overflows to the Catawba River via the Wastewater Collection Basin (WWCB), Outfall 005. The pond also receives storm water runoff from a drainage area of approximately 100 acres. At times, the RN System is aligned to take suction from the SNSWP and discharge back to the SNSWP. This recirculation mode is used for testing purposes of the RN system and flow balances. As a result of accelerated corrosion of RN System components, some components have corrosion inhibitors added. Corrosion inhibitors may contain nitrites, borates, carbonates, silicates, hydroxides, triazoles, and azoles. Low levels of one or more of these corrosion inhibitors would be discharged at environmentally acceptable levels. Macrofouling by Corbicula (Asiatic clams) and Dreissena (Zebra Mussels) can impact the safe operation of the station. Zebra Mussels have not been problematic to date in Lake Norman but other utilities have experienced macrofouling with Zebra Mussels. Microbial influenced corrosion (MIC) has caused failures of piping and heat exchanger tubing due to pitting. Non - oxidizing biocides, chlorine, or sodium hypochlorite may be used at concentrations, which will not impact the environment to address macrofouling and MIC. Surfactants, which act as biopenetrants may be added along with biocides to improve their efficacy. To prevent mud fouling of components cooled by the RN System, dispersants are added. CONTAINMENT SPRAY HEAT EXCHANGERS In order to mitigate corrosion of carbon steel, a wet lay-up system is being used on the Containment Spray Heat Exchangers (NS). Various corrosion inhibitor solutions containing nitrites, borates, azoles, and triazoles may be used. The corrosion inhibitor solution is released 5 to 10 times per year per heat exchanger (2 heat exchangers per unit) to either the SNSWP or Lake Norman via Outfall 001, during the flow balance and heat exchanger performance testing. Each heat exchanger has a capacity of 3600 gallons. Organic biocides are added for biofouling control. Page 5 of 24 CONVENTIONAL LOW PRESSURE SERVICE WATER The Low Pressure Cooling System (RL) supplies cooling water for various functions on the secondary (steam) side of the station. The system takes suction from the RC crossover lines and supplies cooling water to various motor bearings, seals, lube oil coolers, vacuum breaker valves, and a blowdown separator. Discharge is normally back through the RC System. RL is the supply for the plant's Outsourced Water Treatment System (OWTS). FIRE PROTECTION SYSTEM The Fire Protection Systems (RF/RY) provides the plant with fire protection water. The system is equipped with two 200 GPM jockey pumps which take suction from the RC System. One pump is capable of maintaining system pressure. However, the second pump is used to supplement the jockey pump system capacity. In the event the jockey pumps can no longer supply enough water to maintain systern pressure, there are three 2,500 GPM main fire pumps that will start as necessary to maintain system pressure The fire protection system is treated with an oxidizing biocide, when water t,,mperatures are greater than 620 F, to a concentration of approximately 1- 4 ppm total residual oxidant, to control bio -growth in the system's piping. The fire protection system uses sodium silicates for corrosion control. The fire protection system is used as the back -ug source of water for bearing lubrication and gland seal on the low level intake pumps. System operability is demonstrated by periodically testing of the system. A summary of the current testing schedule follows: Monthly, the main fire pumps are started, then stopped, to assure operability. Pump Suction is taken from Lake Norman and discharged directly back into the lake. The water used for this testing is un -treated lake water. Each valve on each hydrant is stroked semiannually to assure proper operation. At this same time, each hydrant is opened and flushed to verify flow. Very little water is discharged. Any water discharged during testing is discharged to yard drains which discharge to the SNSWP or WWCB. Other routine tests are performed periodically to ensure operability of the RF/RY System. These tests include pump head curve and pump starts in which the water is recirculated back into Lake Norman at the Intake Structure. Water is also pumped through the system to ensure there are no obstructions in the lines. OUTFALL 001 Inputs to Outfall 001 include discharges from the RC, RL, and RN systems. Outfall 004 combines with Outfall 001 before discharging into Lake Norman. Storm drains along the discharge canal also discharge to Outfall 001. Condenser Cooling Water The RC System is a once through, non -contact cooling water system that removes heat rejected from the main and feedwater pump turbine condensers and other miscellaneous heat exchangers. Page 6 of 24 Each of the two power generating units has four RC pumps for a total of eight (8) pumps. The flow for each unit depends on the number of pumps operating as shown by the following table: Number of Pumps Operating Total Flow/Unit (GPM) 1 254,000 2 640,000 3 867,000 4 1,016,000 The operational schedule of the pumps of each unit is a function of the intake water temperature and the unit load. At 100% load and with the intake temperature near its summer high four RC pumps per unit are used. During winter when intake temperatures are lower, three pumps may be used. Condenser cleaning is accomplished by mechanical means using the "AmertapTM" system. This system circulates small sponge rubber balls through the condenser continuously. There are 8 AmertapTM pumps per unit, 16 altogether. Each system (2 systems per unit, one for main condenser and one for the FWPTs (Feedwater Pump Turbines) has a capacity of approximately 1240 balls. The balls are injected on the inlet side of the condenser and are retrieved on screens on the discharge side of the condenser. Periodically some balls escape the retrieval system and are discharged through Outfall 001. Efforts are made to minimize the loss of balls within the system. It may become necessary at times to institute chemical control for macroinvertebrate infestation, general corrosion, and microbiologically induced corrosion (MIC). Chemicals anticipated to be added include chlorine (sodium or calcium hypochlorite), organic biocides, dispersants, and corrosion inhibitors. The corrosion inhibitors include nitrites, carbonates, triazoles, borates, triazoles, and azoles. Discharge concentrations are maintained below permitted discharge levels. MNS has identified the need to treat for Asiatic clams in a section of the RC system. The site has determined that clams are present in a "crossover pipe" that connects the U1 and U2 RC systems. The clams have caused fouling of plant components. It is planned to periodically perform localized injections of a clamicide, EVAC, into the crossover pipe section. The injection concentrations will be kept at a level to prevent toxic conditions at the plant discharge. Discharge concentrations of any treatment chemicals will be maintained below permitted discharge levels. Ventilation Unit Drains The Ventilation Unit Condensate Drain Tanks (VUCDT) collects condensate from air handling units from each reactor building. Each VUCDT (1 per unit) has a volume of 4,000 gallons. This condensate typically has little radionuclide contamination. The condensate is sampled for radionuclide contamination before being released. If the results of this sampling indicates the need, the VUCDT contents are transferred to the Floor Drain Tank (FDT) for processing through Page 7 of 24 Outfall 004. If no processing is needed, the condensate is released from the VUCDT via the RC System piping to Lake Norman (Outfall 001). Note: Outfall 004 and the VUCDTs discharge through the same piping to Lake Norman through Outfall 001. During refueling outages, a portion of the ice in the ice condenser is melted. The ice melt is normally routed to the WC system via the Turbine Building Sumps, however on occasion the ice melt may be routed through the VUCDT. This drainage contains small amounts of boron. Boron is used as a neutron absorber in the ice to control reactivity. During outages the KC Heat Exchangers may be drained to the VUCDT as well. Permission was granted for this discharge in a permit modification approved by NCDENR on April 11, 2002. 316 (a) Study and Thermal Variance A 316(a) study was submitted to the state on August 9, 1985 and a 316(a) variance was granted on October 18, 1985. Plant operating conditions and load factors remain unchanged and are expected to remain so for the term of the permit. An annual Lake Norman aquatic environment maintenance monitoring program was implemented on July 8, 1987. A copy of this report is submitted annually to the Environmental Sciences Section of the Division of Water Resources at NCDENR and to the NC Wildlife Resources Commission (NCWRC). No obvious short term or long term impact of station operations have been observed in water quality, phytoplankton, zooplankton or fish communities since the inception of this program. Additionally, Duke Energy is not aware of any changes to plant discharges or other discharges in the plant site area which would negatively impact the thermal discharge or biological habitat of Lake Norman. The annual reports show that Lake Norman continues to have a balanced indigenous population of fish and other aquatic organisms. There were multiple fish kills in the viclinity of the McGuire Nuclear Station Intake during the current permit period, most recently in 2012. The NCWRC) and Duke Energy Fisheries Personnel have investigated the fish kills and have determined they were due to natural lake conditions and not associated with McGuire Plant operation. The NCWRC summarized the 2012 event`. Investigators witnessed the reoccurrence of a striped bass kill on Lake Norman (Mecklenburg County) during July 2012. Nearly 1000 dead fish were recorded near the dam. Striped bass kills in North Carolina reservoirs are not unusual in summer months as high temperatures deplete oxygen in the middle and lower levels of the lakes, trapping bass that appear to be feeding o1i seeking refuge in lower depths. Lake Norman also experienced a similar kill of various catfish species in the same location in early August 2012 (1200 fish). Based on underwater camera footage and recent lake testing, Duke Energy investigators suspected catfish encountered low dissolved oxygen water while chasing and feeding on prey. 1 North Carolina Department of Environment and Natural Resources (NCDENR) 2012. North Carolina Division of Water Quality (DWQ) Annual Report of FishlKill Events — 2012 NCDENR-DWQ. Raleigh, NC Page 8 of 24 OUTFALL 002 Outfall 002 discharges treated wastewater from the Conventional Wastewater Treatment (WC) System through a Parshall flume to the Catawba River below Cowans Ford Dam. The WC System consists of a polyurethane coated concrete Initial Holdup Pond (200,000 gallon capacity), two parallel PolyflexTM Textured HDPE geomembrane-lined Settling Ponds (2 5 million gallons each), and a concrete based Geothane Lined Final Holdup Pond (1 million gallon capacity). Normally, inputs are received in the Initial Holdup Pond (IHP) but can be routed directly to an in-service Settling Pond if needed. The IHP serves as a common mixing point for all wastewater, a surge dampening function to the remainder of the system, and also allows heavy solids to settle for periodic removal. Retention time in the IHP is 12 to 24 hours. Solids removed from the IHP are dewatered and disposed of in a permitted landfill. Flow is directed from the IHP to the in service Settling Pond. Caustic, acid, and/or other chemicals may be added as necessary. Sulfuric acid and sodium hydroxide may be added for pH control or to precipitate various chemical compounds. Coagulants may be added to facilitate the settling of lighter solids. Additional treatment may include chemical oxidation with hypochlorite (calcium or sodium) or catalyzed hydrogen peroxide. Retention time for each of the settling ponds ranges between 6 and 12 days. The Settling Ponds can discharge to the FHP or directly to the Catawba River. Treatment and discharge are normally on a batch basis. During normal operations, the FHP is bypassed. The FHP can be aerated and may be used to remove any persistent oxygen demand or provide additional holdup capacity. The capability is available for recirculation intra- or inter- basin. Discharge to the Catawba River is being modified in the summer of 2014 to be a gravity only discharge with an approximate flow rate between 600 and 1100 GPM determined by pond level. The pH of the discharge from the WC System is adjusted to within permitted limits by the automatically controlled addition of CO2 (carbon dioxide). The WC System accepts all conventional plant wastes except sanitary sewage. Inputs to the system are from the Turbine Building Sumps, Water Treatment Room Sump, Closed Cooling Systems, the Standby Shutdown Facility, Diesel Generator Room Sumps, Laboratory Drains, Landfill Leachate. Steam Generator Blowdown, Wet Layup Drains, and the Unwatering Pump discharges may occasionally be routed through this system as well. Several other buildings also have inputs to the WC system, including the Vehicle Maintenance Facility, McGuire Office Complex, Nondestructive Examination Lab, Island Labs, and the McGuire Medical Facility. These systems typically contain low levels of radioactive hydrogen (tritium). The activity is monitored and accounted for as part of the radioactive release process. Water Treatment Room Sump The demineralized water system (YM) for the plant is produced in a separate building located to the southwest of the Administration Building. Inputs to the Water Treatment Room Sump are minimal and may consist of rinsate of empty hydrazine, ammonia, carbohydrazide, dimethylamine containers and backflow preventer drains. In addition, floor wash and sample Page 9 of 24 line flush water are routed to this sump. Antifoaming agents and wax strippers are routinely present in this waste stream. Rinsate from empty microbiocide containers (used in the closed cooling systems) are periodically added to this sump. The drains in the plant Auxiliary Electric Boiler Room also route to this sump. Additionally, inputs from the McGuire Island Industrial Waste System are routed to the sump. See the Island Industrial Waste section for additional details on these inputs. The Water Treatment Room Sump discharges to the WC System via the Initial Holdup Pond. Filtered Water System The filtered water system has been abaridoned in place and is no longer used. Drinkiniz Water Drinking Water for the McGuire Site is supplied by the Charlotte/Mecklenburg Utility Department. Demineralized Water Svstem Outsourced Water Treatment Building (OWTS) The site has replaced the plant water treatment system with a vendor operated system. While the process is similar, there are some changes to waste streams. The treatment process consist of chlorination, filtration, dechlorination, reverse osmosis, electrodeionization (EDI) and ion exchange. Sodium hypochlorite is used for chlorination. Instead of diatomaceous earth filters, ultrafiltration (UF) is used. This eliminates the waste filter media (DE) that was previously produced. The OF filters are backwashed periodically to remove accumulated lake solids. At times cleaning cycles are combined with backwashes for the OF filters. Sodium hypochlorite, hydrochloric acid and sodium hydroxide may be used to clean the OF fibers. Backwash and cleaning waste water is routed to the WC system Initial Holdup Pond for treatment. OF filtered water is pumped to a 25,000 gallon storage tank at the new building. The new process does not use carbon filtration, eliminating carbon filter backwash wastewater and the need to dispose of waste carbon Sodium bisulfite is used to dechlormate filtered water before it is pumped to the reverse osmosis units and OF Filter backwash water prior to it being discharged to the Initial Holdup Pond. Reverse osmosis is performed with reject flow, approximately 100 gpm max flowrate, routed to the Wastewater Collection Basin. Anti,3calents are infected into the RO feed. The RO system requires periodic cleaning using surfactants, acids or caustic chemicals. Any spent cleaning solutions are routed to the WC system for treatment. The new system employs an electrodeionization (EDI) unit to remove dissolved minerals from the water. Reject water from the EDI unit is sent back to the OF filtered water storage tank for reprocessing. The EDI unit is also cleaned periodically with the same cleaning system used for RO. Page 10 of 24 The demineralization system consist of modular, replaceable mixed ion exchange resin beds. When the resin beds are exhausted, they are replaced with new resin beds and transported off site for regeneration. This eliminates the demineralizer waste streams including the 75,000+ gallons of regenerant wastes previously sent to WC. Turbine Building Sumps The Turbine Building Sumps (TBS), one for each unit, receive inputs from leakage, drainage, and liquid wastes from equipment and floor drains located in the Turbine Building. Inputs include Groundwater Drainage Sumps (WZ), Auxiliary Electric Boiler Blowdown, Steam Generator Blowdown, air handling units, Diesel Generator Room Sumps, lab drains, floor washes, normal condensate system leakage, and condensate polisher backwashes. Other possible inputs may include RC Un -watering, closed cooling system drainage, and steam generator wet lay-up/drain down. Periodically, condensate from air compressors is processed through an oil water separator and routed to the TBS then to the WC Initial Holdup Pond. The TBS's pump out to the WC Initial Holdup Pond. If radioactivity limits are exceeded, theses sumps may be routed through the Radwaste Liquid Waste Monitoring (WM) System (Outfall 004) or directly to RC (Outfall 001) depending on the treatment needed. All radioactive releases are controlled and regulated by the Nuclear Regulatory Commission (NRC). Discharges from the TBS may also be routed to RC (Outfall 00 1) if system inventory is high or for periodic testing. Chemicals that may be present in the TBS include the following: • ammonia • hydrazine • carbohydrazide • 3-methoxypropylamine (MPA) • dimethylamine (DMA) • Glycol (standby diesel coolant) • microbiocides • corrosion inhibitors (examples include: molybdate, nitrite, tolyltriazole, etc.) • janitorial cleaning products • ethylene glycol (from ice melt) • Boric Acid / Borax (from ice melt) • miscellaneous system/component cleaning products (low—volume wastes not associated with chemical metal cleaning) • laboratory chemicals • poly acrylic acid (PAA) • surfactants • dispersants During refueling outages, a portion of the ice in the ice condenser is melted. The ice melt is routed to WC via the Turbine Building Sumps. This drainage contains small amounts of boron. Boron is used as a neutron absorber in the ice to control reactivity. Additionally, small amounts of oil have also been found to accumulate on the ice in the ice condensers. The source of the oil is from pneumatic tools used to vibrate the ice from the condenser's ice baskets. Page 11 of 24 Diesel Generator Room Sumps The Diesel Generator Room Sumps (WN), receive inputs from the leakage or drainage of the four, diesel generator engine cooling water, fuel oil, and lubrication systems. Each diesel generator room has two sumps. The smaller sump has a volume of 600 gallons and one pump with a capacity of 25 GPM. The larger sump has a volume of approximately 4,000 gallons and contains two pumps with a rated capacity of 450 GPM each, and a third pump, with a rated capacity of 50 GPM. Fuel oil and lube oil is collected in the "drip tank" which is then pumped to the Waste Oil Storage Tank (WOST). Each of the four engine cooling water systems has a volume of 800 gallons. The systems may be treated with various corrosion inhibitors which may contain molybdate, hydroxides, borates, silicates, triazoles and azoles. Miscellaneous biocides and dispersants may also be added. Each cooling system is drained and the coolant is recovered , approximately once per year. Additionally, the fuel oil used in the diesels contains fuel stabilizers and a biocide which is added to reduce bacterial breakdown of the oil during storage. Lab Drains There are several analytical laboratorieE on site which discharge to the WC System. These discharges contain small quantities of typical laboratory chemicals used in analytical procedures. The island environmental labs discharge to the WC System as well. Further discussion of this waste stream is provided in the Island Industrial Waste section on page 16. The lab sinks in the Island Technical Services Center (TSC), building 7406, drain to CMUD. There are signs on all of the TSC lab sinks telling lab personnel not to dispose of any chemicals down the lab sink drains. There is very little chemical use in these labs. The TSC labs perform weight calibration, and sound and vibra.ion analysis. Condensate Polisher Backwash Over time, trace impurities in the condensate system increase in concentration. In order to maintain the integrity of the condensate system, the condensate is processed through condensate polishing vessels. Each unit has 4 vessels. Condensate polishers act as filters and if chemistry conditions require it, an overlay of ion exchange resin is added over the filter elements. The resin allows for the capture of soluble contaminants. On average, the vessels are backwashed on a monthly basis. If conditions require, backwashes are performed more frequently. Each backwash requires approximately 10,000 gallons of condensate or YM water When ion exchange resin is used, the backwash well also contain 15-20 cubic feet of resin and 120 milliliters of polymer. Backwash water is discharged to the WC system. When resin is used, the backwash is routed to a decant tank where the resin is captured. Normally, the spent resin is pumped into a liner, de -watered and shi?ped to a low level radioactive waste disposal site. This resin may also be discharged to the WC System or to the Liquid Waste Monitoring System (WM) depending on levels of radioactivity and volume. Page 12 of 24 Steam Generator Blowdown There are four steam generators (SG) per unit at McGuire for a total of eight steam generators. Each has an operating volume of 16,000 gallons. Each unit is provided with a Steam Generator Blowdown Recycle System. Steam generator blowdown is continuous at a rate of approximately 200 gallons per minute per unit. Normally, the blowdown is directed to either the condensate polishing demineralizers or to the steam generator blowdown demineralizers. SG Blowdown can be routed to the WC System via the Turbine Building Sumps if needed. During normal operation, hydrazine is added to the condensate system for oxygen scavenging. The hydrazine concentration is maintained within a range of 25-200 ppb. 3-methoxypropylamine is added for pH control The steam generators and hotwell are placed in wet lay-up if a unit is to be in extended shutdown or per management direction. Each unit is normally shutdown every 12 —18 months for refueling and maintenance. Dispersants may be used in the plants Steam Generators to control corrosion and sediment buildup, therefore the potential exists that refected blowdown waste water may contain small amounts of the dispersant. Steam Generator Wet Lav -u Wet lay-up is the method used for protecting the steam generators against corrosion during inactive periods Typically, this will only be performed 1-2 times during a unit outage. Chemical additions are made up in a 150 gallon addition tank. Nonnally, 40 gallons of 12% Carbohydrazide and 20 gallons of 40% 3-methoxypropylamine (MPA) are made up for transfer to the steam generators. Any remaining chemical solution is drained to the WC System via the Turbine Building Sump. Prior to returning the unit to operation, the wet layup solution in the steam generators may be drained to the WC System or WM System via the TBS. The hotwell on each unit has a volume of approximately 250,000 gallons. During each unit shutdown or per chemistry management direction, the hotwell is placed in wet layup. Approximately 300 gallons of carbohydrazide are added to achieve a target concentration of 100 ppm carbohydrazide with the pH adjusted with MPA. If Carbohydrazide is not available, sufficient hydrazine is added to achieve a target concentration of 75 ppm. Prior to returning the unit to operation, this wet layup solution is discharged to the WC System or WM System via the TBS. Auxiliary Electric Boiler Blowdown The Auxiliary Electric Boiler is supplied feedwater from the condensate system. Trisodium phosphate is added as an electrolyte. The blowdown from the boiler may contain these chemicals and approximately 1-2 ppm suspended solids. Blowdown is routed to the WC System via the TBS. Page 13 of 24 Groundwater Drainage System The Groundwater Drainage System (W-7) is designed to relieve hydrostatic pressure from the Reactor and Auxiliary Buildings by discharging groundwater collected in sumps to either a yard drain or the TBS. There are three groundwater sumps with two 250 GPM sump pumps each. Two of the sumps discharge to the TBS while the third sump discharges to a yard drain that is routed to the Standby Nuclear Service Water Pond (SNSWP). RC System Unwatering The RC System piping for each of the two units has a total volume of approximately 2 million gallons. Whenever a unit is scheduled for refueling, periodically during other shutdowns, and for condenser tube leaks, the system must be un -watered for purposes of maintenance. Un - watering must continue while maintenance is performed because of leakage by the valves in the approximately 11 foot diameter RC piping. The maximum un -watering rate is approximately 2,000 GPM and the water is essentially untreated lake water. Treated liquid radioactive waste effluent (Outfall 004) discharges into a Drossover line between the RC System of the two units. During un -watering, the possibility exists for trace amounts of radioactivity to be released into the water from the un -watering process because of isolation valve leak -by. All radioactivity is accounted for and regulated by the NRC. The principle discharge route of the un -watering is through the WWCB. However, it may be routed through the WC System for short periods of time. Closed Cooling Systems There are several closed cooling systems within the station. The largest system has a volume of approximately 30,000 gallons. The main components of these systems are constructed of carbon steel. In order to mitigate corrosion of the carbon steel, various corrosion inhibitor solutions which may contain nitrite, borate, carbonate, azole, triazole, silicate, phosphate, and molybdate compounds are used. Dispersants may also be used to control corrosion and reduce fouling. Biocides such as gluteraldehyde, isothiazolm and DBNPA can be used to prevent microfouling. Surfactants which act as biopenetrants may be added to improve efficacy. The systems may need to be drained, individually, for non-rout=ne maintenance. Should this occur, these systems would be drained to the RC discharge, WC System, or WM System, if contaminated with radioactivity. Standby Shutdown Facility The Standby Shutdown Facility (SSF) is an alternate and independent means to shutdown the station during emergencies should the need arise. The independent power supply for the SSF is a diesel generator system. The SSF contains a sump to collect system leakage, floor wash, and drainage of the equipment for maintenance. The closed cooling system for the diesel generator uses corrosion inhibitors which may contain nitrite, borate, carbonate, azole, triazole, silicate, phosphate, glycol and molybdate compounds. Biocides such as gluteraldehyde, isothiazolin and DBNPA can be used to prevent microfouling. Surfactants which act as biopenetrants may be added to improve efficacy. Based on maintenance requirements and/or system chemistry monitoring, system coolant is drained and captured for re -use or recycling. Page 14 of 24 Steam Generator Cleaning Each electrical generating unit contains four steam generators that have a capacity of approximately 25,000 gallons each. There has been no chemical cleaning of the steam generators to date, but the possibility exists that cleaning may be required. The actual chemicals used for cleaning will depend on the type of fouling, and may include use of the chemicals listed below. Miscellaneous System/Component Cleaning Other systems/components (such as strainers, piping, HVAC heat exchangers, etc.) are cleaned periodically because of scaling or plugging. Some cleanings are done by rinsing or by high pressure washdown with water only (hydrolasing). Other times additives may be used to improve cleaning efficiency. Solutions utilized are dilute acids, caustics, detergents or other cleaning agents that do not attack the base metal Typically only small volumes of waste are generated. Chemicals utilized by these methodologies, alone or in combination, may include the following: Alkaline Boilout Solutions non-ionic surfactants anionic surfactants cationic surfactants sodium hydroxide soda ash trisodium phosphate disodium phosphate monosodium phosphate sodium bicarbonate Acid Solutions hydrochloric acid sulfuric acid phosphoric acid formic acid hydroxyacetic acid sulfuric acid citric acid nitric acid Acid Solution Additives thiourea ammonium bifluoride oxalic acid Page 15 of 24 EDTA Compounds and HEDTA pH adjusted tetra -ammonium EDTA tetra -ammonium EDTA di -ammonium EDTA hydroxyethylenediaminetriacetic acid tetrasodium EDTA Miscellaneous Compounds chlorothene sodium chloride potassium permanganate aqua ammonia ammonium persulfate antifoam sodium sulfite chlorine The wastes from these cleanings are analyzed to determine proper waste disposal. These cleaning solutions are released through =he WC System or WM System depending on levels of radioactivity. Island Industrial Waste Industrial Waste from the McGuire Island is collected and routed to the plant Water Treatment Room Sump and eventually to the WC System through a dedicated discharge pipe. Industrial Waste consists of small quantities of lab chemicals from analysis in the Duke Energy Corporate Labs in Building 7405 and Building 7403 (McGuire Technical Training Building), and some low level radioactive liquid waste. The radioactive waste is accounted for through McGuire's radioactive effluent license. Landfill Leachate The McGuire Site operates a synthetically lined landfill (Permit 60-04 Indus), which is located on Duke Energy property, across Highway 73, from the McGuire Plant. The landfill began operation in January 1992. The area of the landfill is approximately 5 acres.. The landfill accepts only non -hazardous solid wastes, which contain no free liquids. The leachate collection system is designed to collect rainwater that falls directly onto the landfill. In the landfill cells, a perforated pipe collects the leachate which is then routed to the leachate collection pond. The leachate system is designed to collect a maximum of 68,000 gallons. From the leachate collection pond, the leachatz is pumped to the WC System Initial Holdup Pond. The Leachate also contains pump seal water which comes from a well at the landfill. The estimated average flow from the landfill leachate system is 200 GPD. This will vary according to rainfall amounts. The leachate is sampled semi-annually. The results are submitted to the N.C. Department of Environment, Health, and Natural Resources, Solid Waste Section, per the Landfill permit requirements. Page 16 of 24 McGuire Garage The McGuire Garage conducts maintenance on a variety of vehicles and heavy equipment. Examples include cars, trucks, boats, fork lifts, cranes, etc. All industrial waste generated at this facility is routed through an oil water separator to the WC System via the Initial Holdup Pond (IHP). To add weight to some equipment, water is added to the tires. To prevent the water from freezing, calcium chloride is added. Approximately 500 gallons of this solution is generated each year. Some of this solution is reused. Portions that are not reused are disposed of in the Initial Holdup Pond. McGuire Office Complex All industrial waste generated in this building is routed to the WC system via the Initial Holdup Pond. Waste from an oil water separator is also routed to the WC system. The average daily flow has not been be estimated due to the highly intermittent nature of the flow but it is expected to be less than 5 GPD (Gallons Per Day). Office Shop Facility All industrial waste generated in this building is routed to the WC system via the Initial Holdup Pond. Waste from an oil water separator is also routed to the WC system. The average daily flow has not been estimated due to the highly intermittent nature of the flow but it is expected to be less than 5 GPD (Gallons Per Day). Nondestructive Examination Current trend is the use of computed radiography (CR) which uses a plate to capture the image and the image is scanned directly into the computer. This method does not produce a waste stream. The method described below may be used as an alternate process backup and as the process to support other Stations. Nondestructive Examination (NDE) includes X-ray testing of various components. The photographic waste from X-raying is routed to the WC system via the IHP. NDE is usually conducted in a building inside the protected area. If this X-ray processing unit is unavailable, then a trailer which has the same type of equipment is utilized The trailer also discharges the photographic waste to the WC System via the IHP. When operating, the X-ray processing unit has a waste stream which consists of approximately 0.0059 GPM developer replenisher working solution, 0.0297 GPM fixer and replenisher working solution and 4.0 GPM water. The developer replenisher working solution contains hydroquinone, glutaraldehyde, and potassium acetate. The fixer and replenisher working solution contains ammonium thiosulfate and sodium sulfate. Other developer working solutions and /or fixer replemsher working solutions with other constituents may be substituted in the future. Silver is recovered from the process unit flow before it enters the waste stream. The developing process can be operated a maximum of 30 hours per week (4.3 hours/day) but averages only 6 hours per week (1.2 hours/day). Operation of the developing process results in a maximum of approximately 1040 GPD, with an average of 290 GPD of photographic waste discharging to the WC System. Page 17 of 24 Ice Condenser During refueling outages, ice melt from the plants ice condenser is routed to WC. Potential chemicals in ice melt include: • Borax • Boric Acid • Trace amount of oil from ice removal pneumatic tools • Ethylene Glycol from spills fror_i the ice making equipment. The amount of Ethylene Glycol in the ice melt would be <55 gallons total. OUTFALL 003 Outfall 003 was eliminated as of June 28, 1998. All sanitary wastewater is now discharged to the Charlotte/Mecklenburg Utilities Department (CMUD). OUTFALL 004 Outfall 004 discharges wastewater from the Radwaste Liquid Waste Monitoring System (WM). This discharge combines with RC water before discharging through the concrete discharge structure (Outfall 001) into Lake Norman as a batch discharge. All radioactive and potentially radioactive liquids are collected, segregated, sampled and processed as needed prior to release. These effluents are classified as recyclable or non -recyclable liquids. Recyclable liquids are recirculated back to their process streams. Non -recyclable liquids are collected and processed to Nuclear Regulatory Commission (NRC) requirements per 10 CFR Part 20 and 10 CFR Part 50 requirements prior to release. The type of processing depends on the type of waste. The maximum discharge rate from WM is 120 GPM. The batch discharge flow for a Waste Monitor Tank Release is a function of activity level, the number of RC pumps in operation, and the resultant boron concentration in Lake Norman. The WM collects waste in three subsystems; floor and equipment drains, laundry waste, and ventilation unit drains. Chemicals that may be present in the WM System include: boric acid borax nitrate ammoma carbohydrazide Dimethylamine (DMA) 3-methoxypropylamme (MPA) coagulants (example: Nalco 71259 lithium hydroxide ethylene glycol (from ice melt) corrosion inhibitors (examples ir_clude: molybdate, nitrite, tolyltriazole, etc.) hydrazine chlorine/hypochlorite hydrogen peroxide pump bearing cleaning chemicals laboratory chemicals Page 18 of 24 surfactants polyelectrolytes miscellaneous system/component cleaning waste (low volume waste not associated with chemical metals cleaning) microbiocides tool and component decontamination waste janitorial cleaning products. The TBS can become contaminated with radioactivity. When this occurs, it can be pumped to the Floor Drain Tank (FDT) or to the WM release point in the RC crossover line. Any chemicals listed as being in the TBS have the potential to be present in the Waste Monitor Tank (WMT) when the sump is routed to WM Any solids generated in the treatment process are de -watered and transported to a State licensed low level radioactive waste disposal facility. Floor, Equipment, and Laundry Drains Floor drains in the Auxiliary Building, drainage from all equipment (pumps, tanks, heat exchangers, etc.) which process radioactive waste, waste from showers in the change rooms and washing equipment which is used to decontaminate protective clothing, and waste from the Unit 1 and Unit 2 Containment Floor and Equipment Sumps are routed to the Floor Drain Tank (FDT), Waste Evaporator Feed Tank (WEFT), Auxiliary Floor Drain Tank (AFDT), Auxiliary Waste Evaporator Feed Tank (AWEFT), and/or Laundry and Hot Shower Tank (LHST). The total tank volume is 125,000 gallons. These collection tanks are used interchangeably and/or as backup and surge capacity for waste collection upstream of processing. Radioactive waste from these collection tanks are processed using filters and/or demineralizers based on content. The processed effluent is collected in the Waste Monitor Tanks for sampling and analysis prior to release. Release is to Lake Norman via the RC crossover line. Chemical Volume and Control System The Chemical Volume and Control System (NV) regulates the concentration of chemical neutron absorber in the Reactor Coolant System (NC) to control reactivity changes and maintain the required water inventory in the NC System. Boron, as boric acid is used as the chemical neutron absorber. Other control elements introduced into the NC System by the NV System include lithium and/or carbohydrazide or hydrazine. Approximately 120 pounds of lithium hydroxide monohydrate is used in each unit per year for pH control. The lithium is removed by demineralizers in the NC System. Zinc acetate dihydrate is added to the NC system to achieve a concentration of 10 ppb as zinc. This is done to reduce radiation exposure to plant personnel. Zinc will be removed by demineralization in the NC system and by uptake into NC system piping oxide layers and corrosion product deposits on fuel cladding During start-up, carbohydrazide or hydrazine is used as an oxygen scavenging agent. It is consumed upon unit heat -up, and is not used at any other time. During shutdown, hydrogen peroxide is added to the NC System to facilitate the removal of activated corrosion products. Page 19 of 24 Chemical Treatment in WM System If it becomes necessary to oxidize sodi (calcium or sodium) or catalyzed hydro performed, the Waste Monitor Tank is ensure that the nitrite has been oxidize, a small residual of nitrite in the tank, si stoicheometncal excess. OUTFALL 005 Outfall 005 discharges flow from the 13.4 acre collection basin having a to maximum drawdown capacity of app ranges from 0 to 20,000 GPM. If the flushed, no holdup of the WWCB is I provides sedimentation, natural neutr mixes with discharge from the WC S the Catawba River downstream of Cc nitrite in a Waste Monitor Tank, hypochlorite ;n peroxide would be used. When this treatment is dated, recirculated, and mixed. The tank is sampled to The addition of the oxidation chemicals should result in e the oxidation chemicals will not be added in aste Water Collection Basin (WWCB). The WWCB is a capacity of approximately 22.7 million gallons with a dinately 11.1 million gallons. Discharge from the basin andby Nuclear Service Water Pond (SNSWP) is being ;sable. Otherwise, holdup is minimal. The WWCB zation, and skimming. The overflow from the WWCB em (Outfall 002) in a concrete apron and is discharged to ans Ford Dam. Inputs to the basin include overflow from the SNSWP, yard drains, RO reject flow, miscellaneous Administrative Building drains, and RC System un -watering. RO reject flow from the Water approximate 3 inch line. f►1 The SNSWP is a 34.9 acre pond design the unlikely event that Cowans Ford Di The level in the pond is maintained, pa Specifications (NRC requirements), by pond receives runoff from a drainage a cleaning solutions (NS System) may oc SNSWP is routed to the WWCB. Macrofouling sources (fish, algae, wee, chemical treatments. Rotenone is used year. Rotenone is added at approximat neutralized through the use of Potassiu: and algae are removed using Hydrotho' in depth or less. Hydrothol treatments spring, summer and early fall. Building (OWTS) is routed to the WWCB through an ;d to provide water for the safe shutdown of the station in n is damaged and Lake Norman becomes unavailable. requirements of the McGuire Nuclear Station Technical Jumping water from Lake Norman into the pond. The ;a of 100 acres. The containment spray heat exchanger ;asionally be routed to the SNSWP. Overflow of the s, etc.) are removed from the SNSWP through the use of o remove fish at a frequency of approximately twice per ly 2 ppm for these treatments. The rotenone is L Permanganate at no more than 4 ppm. Aquatic weeds 191 in the shallow areas of the SNSWP at depths of 10 ft re conducted approximately 3 times a year in the late To ensure that the treatment chemicals are not released to the Catawba River prior to being non- toxic, the WWCB is lowered approximately 5 feet below overflow. Additionally, the SNSWP is lowered approximately 4 inches under dverflow. In order to lower the pond levels, temporary pumps may be used to pump water to tl}e WWCB and Catawba River via the overflow pipe at Page 20 of 24 the peinutted Outfall 005 . Treatments are controlled by procedure. Per agreement with NCDENR toxicity tests are performed on the ponds before water is released to the Catawba River. Administrative Building Drains The Administrative Building drains include an HVAC sump, floor drains, janitorial sink, hot water boiler, and chiller water system discharge. Any chemicals in the drains would include the typical commercial products used to clean and maintain the floors as well as closed cooling corrosion inhibitors and microbicides from leakage/drainage of the HVAC Systems. The corrosion inhibitors may contain nitrite, borate, carbonate, triazole, azole, and glycol compounds. Additionally, HVAC cooling units are periodically cleaned using dilute coil cleaning solutions. These cleaning solutions are typically flushed to storm drains near the building which drain to the SNSWP or the WWCB. Volumes are less than 55 gallons. The coil cleaning solutions are typically Phosphoric Acid or Hydrofluoric Acid based. RC Svstem Un -watering The RC System piping for each of the two units has a total volume of approximately 2 million gallons. Whenever a unit is scheduled for refueling, periodically during other shutdowns, and for condenser tube leaks, the system must be un -watered for purposes of maintenance Un - watering must continue while maintenance is performed because of leakage by the valves in the approximately 11 foot diameter RC piping. The maximum un -watering rate is approximately 2,000 GPM and the water is essentially raw lake water. Treated liquid radioactive waste effluent (Outfall 004) discharges into a crossover line between the RC System of the two units. During un -watering, the possibility exists for trace amounts of radioactivity to be released into the water from the un -watering process because of isolation valve leak -by. All radioactivity is accounted for and regulated by the NRC. The principle discharge route of the un -watering is through the WWCB. However, it may be routed through the WC System for short periods of time. Filtered Water The Filtered Water (YF) storage tanks on the service building roof have been converted to demineralized water (YM) storage tanks. Periodic flushes of the tanks are no longer performed. The Filtered Water system has been removed or reconfigured. HVAC Unit Drains Several HVAC units have once through non- contact cooling water drains which discharge to yard drains on the east and west sides of the Administrative Building. The flow from each of these units is 10 GPM. These HVAC units are supplied by RL. Additionally, HVAC cooling units are periodically cleaned using dilute coil cleaning solutions. These cleaning solutions are typically flushed to storm drains near the building which drain to the SNSWP or the WWCB. Volumes are less than 55 gallons. The coil cleaning solutions are typically Phosphoric Acid or Hydrofluoric Acid based. Page 21 of 24 Yard Drains Most yard drains discharge to the WWCB or SNSWP. The drainage area for the plant site is approximately 250 acres. The yard dram system is descnbed in McGuire's Stormwater Supplemental Information and the sites Storm Water Pollution Prevention Plan (SWPPP). Turbine Building There is a small pit in each unit's turbine building that gravity drains to the WWCB. These pits are part of the drainage grid under the turbine building; no plant waste streams are routed to these pits. OUTFALL 006 System performance standards may require that certain metal components be periodically cleaned usmg an acid or caustic solution. This cleaning process can be reactive with the base metal of the component. The waste metal cleaning solutions which are generated will be neutralized. The other compounds will be mixed, oxidized, and/or precipitated as necessary for treatment. The wastes from these clean_ngs will be sampled and analyzed to determine proper waste disposal. If the wastewater is in specification it will be released through the WC System or WM System. If the waste solution exceeds the permitted discharge limits, it will either be treated further or sent off-site to an approved disposal facility. Page 22 of 24 APPENDIX I Water Use Diagram Page 23 of 24 Standby Nuclear Appendix I Service Water Pond ~— Storn Drains McGuire Nuclear Station SNSWP NPDES Flow Diagram ♦ NCO02439 � I LAKE NORMAN Nuclear Service 22 2 MGD Normal Flowpath `i Waterer ------ Alternate Flowpath I 1 �� I I Low Level Intake Condenser Cooling 2,604 MGD 2,626 Total MGD LAKE NORMAN I ( LLI) _ _ Water RC DISCHARGE i i WW001 i i 0 0079 MGD Low Pressure i —FF_ ire Protection I I 1 i Service Water RL � I i i Rad aste I Ii Filtered Water OversenPrimaryDeWmainteerraYkMzed SystemI System osis UCoolant Drainage (WM) I RO and Leakage I WWO04 I I -----' 1 cn I n a Ventilation Unit i *Garage Vehicle m Condensate Drain Wash Area Water Treatment Secondary System m Tanks (VUCD T) i *Landfill Leachate i Room Sump Drainage and 0 0 0015 MGD `----- o Leakage I I H I --------------- Waste I *NDE Photographic °' ------ � -- 3 I G) Conventional Waste m o Waste Treatment •Island Lab Waste C System ----I I 'Island WAC( WC) Towers Turbine (WC) ep Water Building Sump WW002 Se I I arators Stonn Drams 0 3485 MGD I I I i Waste Water ,� I CATAWBA } Collection Basin FI (WWCB) Total 0 9819 MGD RIVER -- WW005 06334 MGD i I I Page 24 of 24