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HomeMy WebLinkAboutNC0001422_Wastewater Application Materials_20150305i t� DUKE L.V.Sutton Energy Complex ENERGY, 801 Sutton SteamPlant Rd Wilmington, NC 28401 PROGRESS o 910.341.4750 f 910.341.4790 February 23, 2015 Mr.Jeffrey 0. Poupart NCDENR-DWR,Water Quality Permitting Section RECEIVEDIDENRIDWR 1617 Mail Service Center Raleigh, NC 27699-1617 MAR 0 5 2015 Subject: Duke Energy Progress, Inc. Water Quality L.V.Sutton Energy Complex NPDES Permit NC0001422 Permitting Secttor NPDES Wastewater Application Materials Dear Mr. Poupart: This letter and the attached materials are provided in response to Tom Reeder's February 6th letter which indicated that the Department of Environment and Natural Resources (NCDENR) is preparing draft NPDES permits for the L.V.Sutton Energy Complex(Sutton Plant). The draft is intended to address NCDENR's November 5, 2014 notice letter reclassifying Sutton Cooling Pond as"Waters of the State". Enclosed with this letter are preliminary application materials to modify the NPDES permit for the Sutton Plant. Specifically we have attached the following materials: • EPA Form 1; • EPA Form 2C, pages 1-4 (sample data to complete the application will be provided once the full constituent analyses of the new outfalls has been completed). • Site map showing the location of all outfalls (internal and final); • An updated flow chart and description of waste flows(Form 2C Attachment 2-Item Il-A); • An updated narrative description of sources of pollution and treatment technologies(Form 2C Attachment 3 Item Il-B); • An updated list of potential items not covered by analysis (Form 2C Attachment 4). Please also consider the supplemental ash pond characterization data submitted on January 20, 2015 as part of this submittal. With reissuance of the permit, Duke Energy also requests that NCDENR staff consider the following: I. Inclusion of Additional Permitted Outfalls • Please add Outfall 008 to the permit to capture the facility's recirculated water discharge and other comingled waste streams,as described in the attached permit materials. This new outfall would be located at the end of the effluent channel and discharge into the cooling pond. Duke Energy staff discussed the location of the effluent channel with your staff on February 2 and concurs with the Wilmington Regional Office's recommendation as to the location and extent of the channel boundaries. I - - CONTINUED FROM THE FRONT VII.SIC CODES 4-digit,in order of.pori A.FIRST B.SECOND 7 4 9 11 I (speci6) . I I I (+pecifY) Electric Power Services 15 18 19 1516 • 19 C.THIRD D.FOURTH 7 I I I (spec•tfy) 7 I I I (spec?6) 1518 19 15 16 - 19 VIII.OPERATOR INFORMATION A.NAME B.Is the name listed in Item I I I I I I I I I I 1 I I I I I I I I I I I I I I I I I I I I I I I I I I VIII-A also the owner? 8 Duke Energy Progress, Inc. 0 YES ❑NO 5 18 5586 C.STATUS OF OPERATOR(Enter the appropriate letter into the answer box:if"Other,"specify.) D.PHONE(area code&no.) F=FEDERAL (specify) S=STATE M=PUBLIC(other than federal or state) P A (910) 341-4775 P=PRIVATE 0=OTHER(specify) Public Utility 56 15 6 - 18 )19 • 21 122 - 28 E.STREET OR P.O.BOX 8011 Sutlton 1Steaml Plantl Roadl 1 1 1 1 1 1 1 1 1 1 1 1 1 1 26 55 F.CITY OR TOWN G.STATE H.ZIP CODE IX.INDIAN LAND t I I I I I I I I I I I I I I I I I I I I l 1 1 IIII Is the facility located on Indian lands? g Wilmington NC 28401 ❑YES 0N i5 18 3041 L2 31 • 51 52 X.EXISTING ENVIRONMENTAL PERMITS A.NPDES(Discharges to Surface Water) D.PSD(.lir Emissions from Proposed.oiisrces) CT ' 1 I I I T I I I I 1 I I CT , I I I I I I 1 1 I I I I 9 N NC0001422 9 P 15 18 17 II 30 15 1817 1e 30 B.UIC(Underground Injection of Elude) E.OTHER specs ) CT 1 I I I I 1 I I I 1 1 1 1 c T I I Wd0U001020 11 I I I I (specify) 9 U 9 NC Ash Utilization 15 1e 17 1e 3015 19 17 18 30 C.RCRA(Hazardous Wastes) E.OTHER(spec) CII I I I I 1 I I 1 l I I I c T i 1 I I I I I I I I I 11 1 (specify) gill NCD000830646 g 165 88CAMA Permit for intake structure 18 30 ill 11 18 30 XI.MAP Attach to this application a topographic map of the area extending to at least one mile beyond property boundaries.The map must show the outline of the facility,the location of each of its existing and proposed intake and discharge structures,each of its hazardous waste treatment,storage,or disposal faciliti s,and each well whereit injects fluids underground.Include all springs,rivers,and other surface water bodies in the map area See instructions for precise requirements. (Attachment 1) XII.NATURE OF BUSINESS(.rovide a briefdescrf.tion) The L. V. Sutton Plant is an electric generating facility consisting of three simple-cycle internal combustion turbine (CT) units and a natural gas-fired 2x1 Combined Cycle (CC) combustion turbine unit. Until November 2013, the plant also operated three coal-fired electric generating units, however those units have been decomissioned and are currently being demolished. XIII.CERTIFICATION(see instructions) I certify under penalty of law that I have personally examined and am familiar with the information submitted in this application and all attachments and that,based on my inquiry of those persons immediately responsible for obtaining the information contained in the application,I believe that the information is true,accurate,and complete.I am aware that there are significant penalties for submitting false information,including the possibility of fine and imprisonment. A.NAME&OFFICIAL TITLE(type or print) B.SIG ' . • C.DAT SIGN D Allen A. Clare �� Station Manager COMMENTS FOR OFFICIAL USE ONLY C is]I6 55 _ EPA Form 3510-1(8-90) EPA I.D.NUMBER(copy from hem I of Form I) Form Approved. MB No.2040-0086. Please rintortype inthe unshaded areas only. NCD 000830646 Approval expires3-31-98. FORMU.S.U.S.ENVIRONMENTAL PROTECTION AGENCY 2C ��EPA GE WASTEWATER EXISTING MANUFACTURING,COMMERCIAL,MININCATION FOR PERMIT TO G AND SILVICULTURE OPERATIONS NPDES Consolidated Permits Program I.OUTFALL LOCATION For each outfall,list the latitude and longitude of its location to the nearest 15 seconds and the name of the receiving water. A.OUTFALL NUMBER B.LATITUDE C.LONGITUDE (list) 1.DEG. 2.MIN. 3.SEC. 1.DEG. 2.MIN. 3.SEC. D.RECEIVING WATER(name) 001 34 16 57 77 59 20 Cape Fear River 002 34 17 33 77 59 35 Sutton Cooling Pond 004 34 17 56 77 59 32 Sutton Cooling Pond 008 34 17 29 77 59 36 Sutton Cooling Pond Il.FLOWS,SOURCES OF POLLUTION,AND TREATMENT TECHNOLOGIES A. Attach a line drawing showing the water flow through the facility.Indicate sources of intake water,operations contributing wastewater to the effluent,and treatment units labeled to correspond to the more detailed descriptions in Item B.Construct a water balance on the line drawing by showing average flows between intakes,operations, treatment units,and outfalls.If a water balance cannot be determined(e.g.,for certain mining activities),provide a pictorial description of the nature and amount of any sources of water and any collection or treatment measures. B. For each outfall,provide a description of:(1)All operations contributing wastewater to the effluent,including process wastewater,sanitary wastewater,cooling water, and storm water runoff; (2)The average flow contributed by each operation; and(3)The treatment received by the wastewater. Continue on additional sheets if necessary. 1.OUT- 2.OPERATION(S)CONTRIBUTING FLOW 3.TREATMENT FALL b.AVERAGE FLOW b.LIST CODES FROM NO.(list) a.OPERATION(list) (include units) a.DESCRIPTION TABLE 2C-1 1984 Ash pond discharge through 4 45 MGD. (2013 average) Sedimentation, neutralization 1-U 2-K 001 diverter structure to Cape Fear River. 1971 Ash pond discharge Sedimentation, neutralization 002 0 MGD• 1-U 2-K Low volume wastes Sedimentation, neutralization, oxidation (2-8), 0.35 MGDprecipitation(2-C),sorption(1-X),reduction(2-L) 1-U 2-K Stormwater Sedimentation, neutralization 0.08 MGD 1-U 2-K Coal pile runoff Sedimentation, neutralization 0.2 MGD 1-U 2-K 1984 Ash pond discharge through 4.45 MGD. (2013 average? Sedimentation, neutralization 1-U 2-K 004 diverter structure to cooling pond. Recirculated cooling water 288 MGD. Evaporation 1-F 008 Non-contact cooling service water0 MGD Evaporation 1-F Low volume wastes Sedimentation, neutralization, oxidation (2-B), 0.96 MGD precipitation(2-C),sorption(1-X),reduction(2-L) 1-U 2-K Stormwater 0.04 MGD Sedimentation, sorption 1-U 1-X • The ash ponds and cooling pond have not discharged since Nov 2013. See Attachment 2 for line drawing showing the water flow through the facility. See Attachment 3 for additional descriptions of contributing flows. OFFICIAL USE ONLY(efuentguidehnes sub-categories) EPA Form 3510-2C(8-90) PAGE 1 of 4 CONTINUE ON REVERSE CONTINUED FROM THE FRONT C.Except for storm runoff,leaks,or spills,are any of the discharges described in Items II-A or B intermittent or seasonal? YES(complete the following table) ❑NO(go to Section III) 3.FREQUENCY 4 FLOW a DAYS PER B.TOTAL VOLUME 2.OPERATION(s) WEEK b.MONTHS a FLOW RATE(ft,mgLI) (.sp.:16..1th umrs) 1.OUTFALL CONTRIBUTING FLOW (spc'eife PER YEAR 1 LONG TERM 2 MAXIMUM 1.LONG TERM 2.MAXIMUM C.DURATION NUMBER(hst) (list) average) (sped i ave'age) AVERAGE DAILY AVERAGE DAILY t"dayT) 001 Ash pond discharge from 004 diverter 0-5 (est) 12 (est) 4.54 MGD 9.84 MOD (expected discharge due to ash pond dewatering or in response to excees (2013 (2013 precipitation) data) data) *flow data is based on 2013 discharges from 004 to Sutton Cooling Pond III.PRODUCTION A.Does an effluent guideline limitation promulgated by EPA under Section 304 of the Clean Water Act apply to your facility? ®YES(complete Item Ill-H) ❑NO(go to Section It') B.Are the limitations in the applicable effluent guideline expressed in terms of production(or other measure of operation)? ❑YES(complete Item 111-(') NO(go to Section 11') C. If you answered'yes'to Item III-B,list the quantity which represents an actual measurement of your level of production,expressed in the terms and units used in the applicable effluent guideline,and indicate the affected outfalls. 1.AVERAGE DAILY PRODUCTION 2.AFFECTED OUTFALLS c.OPERATION,PRODUCT,MATERIAL,ETC. a.QUANTITY PER DAY b.UNITS OF MEASURE (list outfall numbers) (iPecsJi') NA IV.IMPROVEMENTS A. Are you now required by any Federal, State or local authority to meet any implementation schedule for the construction, upgrading or operations of wastewater treatment equipment or practices or any other environmental programs which may affect the discharges described in this application?This includes,but is not limited to, permit conditions,administrative or enforcement orders,enforcement compliance schedule letters,stipulations,court orders,and grant or loan conditions. ❑YES(complete the Jicllowing gable) gl NO(go to Item ll'-f1) 1.IDENTIFICATION OF CONDITION, 2.AFFECTED OUTFALLS 3.BRIEF DESCRIPTION OF PROJECT 4.FINAL COMPLIANCE DATE AGREEMENT,ETC. a NO. b.SOURCE OF DISCHARGE a.REQUIRED b.PROJECTED NA B. OPTIONAL You may attach additional sheets describing any additional water pollution control programs (or other environmental projects which may affect your discharges)you now have underway or which you plan.Indicate whether each program is now underway or planned,and indicate your actual or planned schedules for construction. ❑MARK"X"IF DESCRIPTION OF ADDITIONAL CONTROL PROGRAMS IS ATTACHED EPA Form 3510-2C(8-90) PAGE 2 of 4 CONTINUE ON PAGE 3 EPA I.D.NUMBER(copy from Item I ofForm I) CONTINUED FROM PAGE 2 NCD000830646 V.INTAKE AND EFFLUENT CHARACTERISTICS A,B,8 C: See instructions before proceeding-Complete one set of tables for each outfall-Annotate the outfall number in the space provided. NOTE:Tables V-A,V-B,and V-C are included on separate sheets numbered V-1 through V-9. D. Use the space below to list any of the pollutants listed in Table 2c-3 of the instructions,which you know or have reason to believe is discharged or may be discharged from any outfall.For every pollutant you list.briefly describe the reasons you believe it to be present and report any analytical data in your possession. 1.POLLUTANT 2.SOURCE 1.POLLUTANT 2.SOURCE Retired Coal Units Strontium Occasionally found in coal Uranium Occasionally found in coal Vanadium Occasionally found in coal Zirconium Occasionally found in coal Asbestos Used in insulation CC Block None VI.POTENTIAL DISCHARGES NOT COVERED BY ANALYSIS Is any pollutant listed in Item V-C a substance or a component of a substance which you currently use or manufacture as an intermediate or final product or byproduct? YES(list all such pollutants below) ONO(go to Item VI-B) Retired Coal Units Antimony Arsenic Beryllium Cadmium Copper Lead Mercury Nickel Selenium Silver Thallium Zinc CC Block None See Attachment 4 for other substances used during operational processes or at the plant that potentially may be discharged. EPA Form 3510-2C(8-90) PAGE 3 d 4 CONTINUE ON REVERSE • CONTINUED FROM THE FRONT VII.BIOLOGICAL TOXICITY TESTING DATA Do you have any knowledge or reason to believe that any biological test for acute or chronic toxicity has been made on any of your discharges or on a receiving water in relation to your discharge within the last 3 years? ©YES(idents the test(s)and describe their purposes he/ow) ❑NO(go to Section VIII) 24-hour static acute toxicity tests using fathead minnows were required to be conducted quarterly on the wastewater discharge from Outfall 001 (historically from cooling pond to Cape Fear River) . The facility has passed all toxicity tests. VIII.CONTRACT ANALYSIS INFORMATION Were any of the analyses reported in Item V performed by a contract laboratory or consulting firm? ❑YES(list the name,address,and telephone number of,and pollutants analyzed by, ®NO(go to Section IX) each such laboratory or firm below) A.NAME B.ADDRESS C.TELEPHONE D.POLLUTANTS ANALYZED (area code&no.) (list) NA IX.CERTIFICATION I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system or those persons directly responsible for gathering the information,the information submitted is,to the best of my knowledge and belief,true,accurate,and complete.I am aware that there are significant penalties for submitting false information,including the possibility of fine and imprisonment for knowing violations. A.NAME&OFFICIAL TITLE(type or print) B.PHONE NO.(area code&no.) Allen A. Clare, Station Manager (910) 341-4750 z:::;eC.SIGNATUREle____(2.4 D.DATE SIGNED /� ,,,?/' EPA Form 3510-2C(8-90) PAGE 4 of 4 Duke Energy Progress, Inc. L.V. Sutton Electric Plant NPDES Permit NC00001422 2015 Permit Application Update N Dike 0 500 1000 Makeup Meters Pump 0 1000 2000 3000 Feet Outfall 004 ro 4 Sutton Cooling Pond Q CT New Ash Pond (1984) •Outfal 1002 Outfall 008 (approx) Old Ash Pond (1971) Effluent Channel to Cooling Pond Internal L� utfall 009 Internal(approx) outfall007 (approx • Final (external) Outfalls Cooling Pond • Internal Outfalls Withdrawal Recirculating Condenser Cooling Water Outfall 001 Release CC Block Internal Outfall 006 CC Block Sutton Energy Internal Outfall 005 Complex NORTH CAROLINA NPDES Wastewater Outfalls L. V. Sutton Energy Complex New Hanover County Duke Energy Progress,Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update Attachment 2 Form 2C - Item Il-A Flow, Sources of Pollution, and Treatment Technologies Water Average Flow Path' (MGD) Flow Comments A 72 Maximum river water makeup to cooling pond(intermittent) B 0 Water intake for the coal-fired units C 0 Ash sluice water routed to new ash pond—variable 0-7 MGD D – Flow path removed E 4.45 Outfall 004—Ash sluice water from New(1984)Ash pond to cooling pond(optionally routed to Outfall 001 F 0 Ash sluice water routed to old ash pond—variable 0-7 MGD G 0 Outfall 002—Discharge from Old(1971)ash pond to cooling pond H 4.45 Alternate discharge to Outfall 001 0 Non-contact cooling water(service water)for coal-fired units J 0 Heated water discharge from coal units condensers to cooling pond K 0 Supply well water withdrawal for coal-fired units L 0.17 Low volume waste waters from coal-fired units(estimated) M 0.18 Internal Outfall 007-Maximum flow from the west retention basin . This waste stream is expected to be re-routed from the old(1971)ash pond in 2015. N 0 Internal Outfall 003—Chemical metal cleaning wastes were historically disposed of by evaporation in the boilers; Outfall 003 was an alternate for discharging into an ash pond .These wastes are no longer generated since the retirement of the coal-fired units. O 0.11 Coal pile and tank farm area runoff—estimated 80 dpy(expected to be eliminated by 2015) P - Flow path removed Q - Flow path removed R - Flow path removed S 19.7 Discharge from cooling pond to the Cape Fear River. Estimate based on standard practice. 2013 average was 19.95 MGD for days where there was a release) T 0.0(Coal units); County water for potable water and sanitary systems 0.002(CC block) AA 0.67 Supply well water withdrawal for the combined cycle power block A2-1 Duke Energy Progress,Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update Water Average Flow2 Path' (MGD) Flow Comments BB 0.07 Water treatment filter backwash to Internal Outfall 005 via low volume waste collection sump CC 0.29 Service water to the Closed Cooling Water Cooler(CCWC) DD 0.14 Closed cooling water cooler blowdown discharge to Internal Outfall 005 via low volume waste collection sump EE 0.14 Closed cooling water cooler evaporation and drift losses FF 0.007 Service water for combined cycle power block plant systems GG 0.11 Service water to blowdown tanks HH 0.130 Internal Outfall 006—Heat recovery steam generators blowdown tank discharge to the cooling pond (actual monthly avge since Nov 2013) II 0.033 Blowdown tank flash evaporation JJ 0.12 Demineralized water to Heat Recovery Steam Generators(HRSGs) KK 0.088 Heat recovery steam generators blowdown LL variable Heat recovery steam generators cleaning wastes MM 0.023 Heat recovery steam generators vent losses NN 0-0.02 Auxiliary boiler blowdown 00 0.3 Oil/water separator discharge to Internal Outfall 005 via low volume waste collection sump PP 0.25 Demineralized water to Combined Turbine Generator(CTG)NOx injection system QQ 0.003 Combustion turbine generator wash water and false start losses RR 0.25 Combustion turbine generator NOx injection system water losses SS 0.127 Reverse Osmosis(RO)and Electrodeionization(EDI)water treatment system reject water to Internal Outfall 005 via low volume waste collection sump TT 288 Combined cycle power block recirculated condenser cooling water withdrawal from the cooling pond UU 288 Outfall 008-Combined cycle power block recirculated condenser heated water discharge with comingled wastestreams(to the effluent channel) W 0.64 Internal Outfall 005—Combined cycle power block wastewater discharge to the cooling pond(actual monthly avg since Nov 2013) WW 0.29 Low volume wastes from coal-fired units XX .0072 CT oil water separator(plant drains) YY .078 CT reverse osmosis system reject A2-2 Duke Energy Progress, Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update Water Average Flow2 Path' (MGD) Flow Comments ZZ .085 Discharge from CT low volume waste sump. 'Water path color indication: Blue = Coal-fired units water paths Red = Combined cycle power block water paths Green = Conjoined systems water paths 2Average flow values for the combined cycle power block are estimated based on proposed plant design. A2-3 Duke Energy Progress, Inc. NPDES Permit NC0001422 L. V. Sutton Electric Plant 2015 Permit Application Update Coal-fired units water paths Fast Start CT units water paths —Combined cycle water paths —Conjoined water paths Supply wells County water ®Waste streams removed as of 7/31/14 Water treatment Plant systems Potable water s stem and drains Fire system r West Retention t O/W Sanitary I basin Se arator systems Evaporation I I Yard drains Evaporation Septic tanks I I Internal Internal Outfall003 Outfall 003 i New Ash Pond C Intake structure OldAsh Leach fields I F Pond Screen wash I g I OO D I Makeup water Coal pile &tank Infiltration intake structure , I farm runoff Cape Fear River I Internal Outfall0071 O X A , (Discharge path I Outfall 002 I Stormwater eliminated) G Outfall 004 I E UU Cooling Pond Screen wash Outfall 001 TT Intake structure Effluent Channel H to Outfall 008 S Supply wells Condensers Cape Fear River Internal AA Outfall001 W Outfall 005 Ultrafilter water Filter backwash 9B Low volume waste treatment system collection sump EE Evaporation HH Closed cooling Internal CC i III, water cooler DD Outfall 006 Storm wate 00 Service water FF Plant systems CC block low Oil/water II storage tank volume wastes se arator Internal Coal units low Outfall It Evaporation volume wastes 009 GG Blowdown tanks NN KK Vent losses CT low volume Auxiliary boiler HRSGs tL wastes O ti RR Water loss —off -site disposal O CT RO water RO/EDI water Demin water CTG NOx treatment treatment s stem stora a tanks PP in'ection CTG wash &false start 4 losses —off -site disposal CT Oil/water SS separator A2-4 Duke Energy Progress,Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update Attachment 3 Form 2C - Item Il-B Flow, Sources of Pollution, and Treatment Technologies The L.V. Sutton Electric Plant has three simple-cycle Internal Combustion(IC)turbine units and a natural gas-fired 2x1 Combined Cycle(CC)combustion turbine. Prior to November 2013,the plant operated three coal-fired generating units. These units were retired once the CC block came online and are currently being prepared for demolition. The plant has a 1,110-acre(6,900 acre-ft)wastewater cooling pond on the east side of the Cape Fear River approximately ten river miles upstream of Wilmington, North Carolina. Water is withdrawn from the Cape Fear River,as required,to makeup evaporative and blowdown losses from the cooling pond. Chemical constituents contained in the discharge from the permitted outfall will, in part, be representative of the naturally-occurring chemical quality and quantity of the intake water and will also have chemical constituents of such quality associated with similar discharges for fossil generating facilities of this size, type,and in this geographical location. Either all or part of the elements in the Periodic Table, either singularly or in any combination, may from time to time be contained in the discharge. Prior to 2015, the Sutton Plant had one external permitted outfall to the Cape Fear River. This outfall was a discharge from the cooling pond(Outfall 001)which received all combined wastewaters from the plant (including several internal outfalls). In 2015, Duke Energy provided an updated permit application, upon request of the Division of Water Resources, to support the characterization of the Cooling Pond as Waters of the State. Based on that classification,the site has the following outfalls: • Outfall 001 discharging from the New(1984)Ash Pond through the diverter structure to the Cape Fear River. • Outfall 002(formerly an internal outfall). This outfall discharges wastewater from the Old (1971)Ash Pond to the Cooling Pond. • Outfall 004(formerly an internal outfall). This outfall discharges from the New(1984)Ash Pond through the diverter structure to the Cooling Pond. • Outfall 008. This new outfall primarily consists of recirculated cooling water from the CC generating unit. The outfall is located at a compliance point at the end of the effluent channel into the Cooling Pond. Internal outfalls 005,006,007 and 009 discharge into the effluent channel and contribute to flows at Outfall 008. The waste streams contributing to these outfalls are described in further detail below. Historic Cooling Pond Discharge Historically Sutton Plant's discharge of recirculated cooling water from the Cooling Pond to the Cape Fear River was considered a regulated NPDES outfall. However, due to NCDENR's reclassification of the cooling pond,the only plant waste stream that will be discharged through outfall 001 is the diverted ash pond discharge(see description below). Under current site operations,the cooling pond is not expected to discharge without a concurrent ash pond discharge except for maintenance purposes or in anticipation of an extreme weather event,such as a hurricane,when additional freeboard is needed to prevent overtopping of the pond dikes. These discharges to alter the level of water in the cooling pond would not be regulated under the NPDES permit. Outfall 001 and Outfall 004-New(1984)Ash Pond Effluent from the new ash pond can be discharged to either the cooling pond(to Outfall 004)or to the Cape Fear River(to Outfall 001). Historic practice was to route a minimum of 4.0 MGD to the A3-1 Duke Energy Progress, Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update cooling pond before additional effluent routed to the Cape Fear River. The ash ponds have not discharged since November 2013. In the future,the old ash pond is only expected to discharge as a result of dewatering efforts to facilitate pond closure. A detailed dewatering plan was submitted to NCDENR in January 2015.As described in the Dewatering Plan, dewatering waters may be routed from the old(1971)ash pond,or other site ash storage areas,to the new ash pond for additional treatment and discharge. As the water in the ash pond is lowered,additional treatment may be brought onsite to ensure the ash pond discharge maintains compliance with NPDES permitted limits, such as a portable filtration unit. Historically the plant's routine practice has been to facilitate diverted ash pond discharges (through 001)by concurrently releasing water from the cooling pond. When ash pond releases were being diverted to the Cape Fear River,the cooling pond was drawn down by an estimated 19.7 MGD. Outfall 002-Old(1971)Ash Pond Coal Pile Runoff Storm water runoff from the coal pile is routed to the old ash pond ,which provides neutralization and sedimentation treatment. This waste stream will cease when all material is removed from the coal pile area and final grading has been achieved in accordance with the NCDENR- approved Erosion and Sedimentation Control Plan. West Retention Basin Flows The coal-fired units were decommissioned in November 2013. Upon retirement of the coal fired units,waste streams from processes which historically went to the ash pond are either no longer generated or will be redirected to the west retention basin until closure is complete. Wastewaters may also be properly disposed of off-site. Waste streams from closure activities associated with the coal-fired unit may be sent to the retention basin until closure is complete. These waste streams could include wash waters from various components that would be expected to contain coal-combustion residuals. To support the closure of the old ash pond,the discharge from the west retention basin will be redirected from the New(1984)Ash pond to effluent channel via internal Outfall 007. More detail on these historic low volume waste streams are provided below: • Process water used in the coal-fired units was treated prior to use by an ion-exchange demineralizer which was periodically regenerated with solutions of sodium chloride, sodium hydroxide,and sulfuric acid. Alternatively a vendor was used to provide treatment of plant process water. • Blowdown of boiler water to control boiler chemistry was routed through low-volume prior to discharge in the ash pond. Boiler vacuuming sediment was routed through low-volume prior to discharge to the ash ponds. The precipitators were water washed approximately every 1 to 3 years with the wastewater discharging to the ash pond. • Drains from areas likely to contain oil-filled equipment or storage were routed through an oil-water separator with the effluent routed through low volume prior to discharge to the ash pond. Waste oil is disposed of according to the appropriate regulations. • Laboratory processes produce small amounts of wastewater which were routed to plant drains. A3-2 Duke Energy Progress,Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update • Wash/rinse wastewater from an on-site washing machine was also routed to plant drains. Drains may also convey equipment and machinery wash-down and other miscellaneous facility housekeeping and maintenance activities. Outfall 008-Effluent Channel Recirculated Condenser Cooling Water The condenser cooling water for the CC block is withdrawn from and discharged to the cooling pond.The heated discharge is routed around baffle dikes within the cooling pond to achieve maximum surface cooling efficiency and before being recirculated through the condenser cooling water intake structure. Evaporation,which is estimated to consume approximately 1.5 MGD above natural evaporation rates during times of full operation,effectively cools the heated water discharge. Biological fouling control agents are used on heat exchanger surfaces. Non-contact Cooling Water Non-contact cooling water is also withdrawn from and returned to the cooling pond. This water provides indirect cooling for various equipment by absorbing heat as it passes through a heat exchanger. No direct contact is made with any other equipment or process. Stormwater Historically, stormwater generated onsite that may have had contact with industrial activity or materials was routed to the old ash pond while exempt stormwater from parking lots or other areas was routed to the effluent channel. In 2015,all site stormwater will be routed to the effluent channel to support ash pond closure activities.There are several discrete stormwater conveyances to the effluent channel including two discharges from stormwater basins(the South Wet Detention Basin and the North infiltration Basin). During certain extreme storm events(e.g.,25-year,24-hour),storm water may inundate areas around the plant site and accumulate beyond design capacity. Storm water collected during these conditions may be pumped directly to the cooling pond or to the surrounding landscape. Internal Outfall 007 In 2015 the discharge from the west retention basin will be routed directly to the effluent channel (see section on Outfall 002 for more details on flows to the west retention basin). . Internal Outfall 005 Drains from the CC block which may contain oil and grease are routed to an oil/water separator before discharging into the cooling pond via Internal Outfall 005. Incidental leaks associated with the operation of the HRSG,Combustion Turbine Generators(CTGs), RO/EDI system,and infrequent draining and cleaning of various processes may generate wastewater that is captured by Internal Outfall 005. During the initial startup phase, HRSG blowdown of up to 1.5 MGD may be released to Outfall 006 for several days. Wastewater from routine HRSG cleaning,fuel oil/water condensate,and equipment drains potentially containing oil is directed to plant drains which are treated by the oil/water separator. The combustion turbine false start drains, NOx injection,and compressor waste water is directed to a holding tank and transported off-site. HRSG chemical metal cleaning wastes may also be generated and hauled offsite. For a more extensive cleaning, the HRSGs may require flushing with a large volume of water. The wastewater from this flushing would be discharged via Internal Outfall 005 to the cooling pond or taken off-site. Various equipment,including fuel oil storage tanks, transformers, lube oil filters,etc.have containment areas for spills. Storm water collected in these areas is visually inspected for the presence of oil prior to release to the ground or released to plant drains which flow to the oil/water A3-3 Duke Energy Progress, Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update separator. Laboratory processes produce small amounts of wastewater which are routed to plant drains. Internal Outfall 006 Process wastewaters generated in the natural gas combined cycle block will be discharged to the cooling pond via two new internal outfalls. Low volume wastewaters including the ultrafilter water treatment system filter backwash, Closed Cooling Water Cooler(CCWC)blowdown, Reverse Osmosis/Electrodeionization(RO/EDI)system reject wastewater,and other wastewaters entering the oil/water separator are directed to the low volume waste collection sump for discharge to the cooling pond via Internal Outfall 005. Low volume wastewaters including the Heat Recovery Steam Generator(HRSG)blowdown and auxiliary boiler blowdown will be discharged to the cooling pond via Internal Outfall 006. Other Site Wastewaters During maintenance activities, sludge removed from basins,sumps,etc.will be transported off- site for proper disposal. Internal Outfall 009 The three existing simple-cycle combustion turbine(CT)units(total 61 MW)are scheduled for replacement in 2017. The two replacement"Fast Start CTs"will have a total generation of 80-90 MW. To support the operation of those units, supporting low-volume waste treatment will be installed. Specifically,the site will install a new oil-water separator to treat service water drains and a reverse osmosis water treatment system. These low volume wastes will be combined in a new low volume waste sump and discharged through a new outfall 009 to the effluent channel. Other Site Wastes Domestic Wastes Sanitary wastes are treated by an onsite septic tank and drainage field that is permitted by the New Hanover County Health Department. The septage is exempt from the 40 CFR 503 standards. Duke Energy Progress, Inc.will submit appropriate information to the EPA if required. Wash/rinse wastewater from an on-site washing machine is also routed to the septic system. Low-Volume Wastes All waste streams not identified above are categorized as low-volume wastes.These wastes include plant drains,which convey miscellaneous equipment leakage,equipment drainage for maintenance, equipment washdown water,sampling streams,service water system blowdown, and water treatment wastes. Any of the chemical additives disclosed in Attachment 4 may be present in Low Volume Wastes. Chemical Metal Cleaning Wastes Chemical metal cleaning wastes were formerly generated during chemical boiler cleaning every 5 to 10 years. The cleaning solution and rinses were stored on site for disposal by evaporation in the boilers. If chemical metal cleaning wastes were not evaporated,they were either treated by neutralization and precipitation in retention basin prior to discharge to the ash ponds, or disposed of off-site. These wastes will no longer be generated with the retirement of the coal-fired units.. Fire Water System Several plant heat exchangers are cooled by the fire water system. Fire water is withdrawn from the cooling pond. A3-4 Duke Energy Progress, Inc. NPDES Permit NC0001422 L.V.Sutton Energy Complex 2015 Permit Application Update Intake Screen Backwash The intake structure from the cooling pond to the former coal generating site will be removed during coal-site demolition. The combined cycle power block has a separate intake structure with an automatic intake screen backwash system that will remain operational. Ash Reclamation In the event a practicable market becomes available, Duke Energy Progress, Inc.,may exercise the option of reclaiming ash from the ash ponds. However,due to the limited scope of such an operation no additional discharges would be expected. Inactive Hazardous Waste Sites List Areas A former ash disposal area and the old ash pond were listed on the State's Inactive Hazardous Waste Sites List. Pesticide Usage in Sutton Cooling Pond Herbicides are used when needed to control nuisance aquatic vegetation. These herbicides are applied by licensed applicators,or persons under the immediate supervision of a licensed applicator, in accordance with the manufacturer's instructions. Pesticides are used when needed to perform biological assessments of fish populations. These pesticides are applied by licensed applicators, or persons under the immediate supervision of a licensed applicator, in accordance with the manufacturer's instructions. A3-5 Duke Energy Progress,Inc. NPDES Permit NC0001422 L.V.Sutton Electric Plant 2015 Permit Application Update Attachment 4 Form 2C - Item VI Potential Discharges Not Covered by Analysis Estimated Quantity Chemical (per year) Frequency Purpose Coal-fired Units Listed chemicals for the coal-fired units are no longer being utilized for the purposes identified below. However,they were used during historic operations and trace amounts have the potential to be discharged during plant demolition. Hydrazine Trace Not actively Oxygen scavenger in boiler used Ammonia Trace Not actively pH control in boiler used Phosphate Trace Not actively pH control in boiler used Sodium hydroxide(50%) Trace Not actively Demineralizer regeneration used Sodium hydroxide(50%) Trace Not actively Ash pond pH control used Sulfuric acid(93%) Trace Not actively Ash pond pH control used Alum Trace Not actively Ash pond total suspended used solids control EcoGreen Barrier Trace As needed Ash pond fugitive dust suppressant BioCover Trace As needed Ash pond fugitive dust suppressant Gorilla Snot Trace As needed Ash pond fugitive dust suppressant Sulfuric acid(93%) Trace Not actively Demineralizer regeneration used Sodium chloride Trace Not actively Water softener regeneration used Bromine/Chlorine[Biotrol 88P(1-bromo- Trace Not actively Control of biofouling on heat 3-chloro-5,5-dimethylhydantoin)] used exchangers Sodium hypochlorite Trace Not actively Control of biofouling on heat used exchangers Sodium molybdate and sodium nitrate Trace Not actively Corrosion control in cooling used water system Cleaner(sodium hydroxide,metasilicate, Trace Not actively Cleaner and ethlenediaminetetraacetic acid) used Ethylene glycol Trace Not actively Equipment freeze protection used Urea Trace Not actively NOx Control used Citric Acid(50%) Trace Not actively Boiler cleaning used Ammonium hydroxide Trace Not actively Boiler cleaning used Cronex Inhibitor Trace Not actively Boiler cleaning used A4-1 Duke Energy Progress, Inc. NPDES Permit NC0001422 L.V.Sutton Electric Plant 2015 Permit Application Update Estimated Quantity Chemical (per year) Frequency Purpose Sodium nitrite Trace Not actively Boiler cleaning used Ammonium bicarbonate Trace Not actively Boiler cleaning used Citric Acid—dry Trace Not actively Boiler cleaning used Tetraammonium Trace Not actively Boiler cleaning ethylenediaminetetraacetic(EDTA),and used ammonium hydroxide AP 1000 Trace Not actively Boiler cleaning used Low hazard corrosion inhibitor Trace Not actively Boiler cleaning used Silicone antifoam agent Trace Not actively Boiler cleaning used Antifoam agent Trace Not actively Boiler cleaning used Liquid oxygen Trace Not actively Boiler cleaning used Powerback Premix with anti-foam agent Trace Not actively IC unit cleaning used Freeze control products(i.e.,varying Trace Not actively Coal freeze conditioning agent solutions of glycol,calcium chloride, used glycerin,diethylene,etc.) Combined Cycle Power Block Hydrazine <8000 gallons Not actively Steam cycle oxygen scavenger used Amine/ammonia <8000 gallons Continuous Steam cycle pH control Phosphate <8000 gallons Continuous Steam cycle scale and pH control Corrosion inhibitor <8000 gallons Continuous Cooling water system corrosion inhibitor Sodium hypochlorite or sodium bromide <25,000 Continuous Cooling water system gallons biofouling control Mineral dispersant <8000 gallons Continuous Cooling water system scale inhibitor Sulfuric acid <8000 gallons Continuous Cooling water system pH control Citric acid <8000 gallons Continuous Water treatment system low pH reagent Sodium hydroxide(50%) <8000 gallons Continuous Water treatment system high pH reagent Sodium hypochlorite <8000 gallons Continuous Inlet water oxidation and filter backwash reagent Potassium permanganate <8000 gallons Continuous Filter inlet water chemical Sodium bisulfite <8000 gallons TBD Plant systems process water dechlorination Sodium bisulfite <8000 gallons TBD Reverse osmosis water system inlet water dechlorination A4-2 Duke Energy Progress,Inc. NPDES Permit NC0001422 L.V.Sutton Electric Plant 2015 Permit Application Update Estimated Quantity Chemical (per year) Frequency Purpose Sodium hydroxide(50%) <8000 gallons Continuous Reverse osmosis water system chemical Anti-scalant <8000 gallons Continuous Reverse osmosis water system scale prevention Bromine antimicrobial(sodium <8000 gallons TBD hypochlorite,sodium bromide,sodium hydroxide) Cooling Pond Vegetation Control Liquid copper-based herbicide(15.9% As needed, Twice/year Lyngbia vegetation control Copper Carbonate) According to manufacturer directions Fluridone-based herbicide(5%fluridone) As needed, Seasonal Macrophyte vegetation control According to manufacturer directions A4-3