April 27, 2010USEPA Steam Electric EGL Site Visit1Safety BriefingUSEPA / AmerenEnergy ResourcesGenerating CompanyDuck Creek Power PlantSteam Electric EGL Site VisitApril 27, 2010April 27, 2010USEPA Steam Electric EGL Site Visit3AgendaIntroductionsSafety BriefingPresentationPlant TourSummaryApril 27, 2010USEPA Steam Electric EGL Site Visit4Ameren CorporationAmeren UEGeneration (~10,400MW)Electric and Gas DistributionTransmissionAmeren Illinois UtilitiesElectric and Gas DistributionTransmissionAmeren ServicesAmerenEnergy ResourcesCompanyAmerenEnergy GeneratingCompany (~4,225MW)AmerenEnergy ResourcesGenerating (~1,125MW)April 27, 2010USEPA Steam Electric EGL Site Visit5Duck Creek Power Plant OverviewOne coal-fired steamgenerating unit:465 MW, nominal430 MW, netCommericalOperation: 1976Non-rate regulatedMISO market areaApril 27, 2010USEPA Steam Electric EGL Site Visit6Air Pollution Control Equipment OverviewSelective catalytic reduction (SCR) system installed in2003 for NOx reductionNew Low NOx burners (LNB) installed in 2007 for NOxreductionNew combustion management system installed in 2007for NOx and CO controlNew Electrostatic Precipitator (ESP) in service March2009 for particulate controlNew Wet Flue Gas Desulphurization (WFGD) system inservice March 2009 for SO2 controlNew concrete chimney installed as part of FGD projectNew continuous emission monitoring system (CEMS)installed and certified in March 2009April 27, 2010USEPA Steam Electric EGL Site Visit7Hitachi Counter Current Open SprayTower (first in US)Absorber Recycle Pump DesignContinuous recirculationAbsorber slurry – pH-5.8, density-70#/ft3SO2 removal – 95%Closed-loop systemWet Flue Gas Desulphurization SystemApril 27, 2010USEPA Steam Electric EGL Site Visit8WFGD System General InformationFGD TypeSpray TowerForced OxidationHorizontal Wet Ball MillAbsorber materialsFlake Glass Lined, Carbon SteelReagent = limestoneApril 27, 2010USEPA Steam Electric EGL Site Visit9WFGD SystemApril 27, 2010USEPA Steam Electric EGL Site Visit10Fly Ash Handling SystemRetrofit during 2005-2006Major componentsPLCHoppersVacuum pumpsTransport lineAsh storage silosTransported to on-site landfill orbeneficial useApril 27, 2010USEPA Steam Electric EGL Site Visit11Fly Ash Handling OverviewApril 27, 2010USEPA Steam Electric EGL Site Visit12Fly Ash Handling OverviewApril 27, 2010USEPA Steam Electric EGL Site Visit13Duck Creek Wastewater ManagementWFGDBottom ashLow volumeLandfill runoff/leachateGypsum stack runoff/leachateCoal pile runoffApril 27, 2010USEPA Steam Electric EGL Site Visit14WFGD ProductsMass Conservation Fundamental:What goes in...Post-precipitator combustion gasLimestoneWater...must go outGypsum slurryScrubbed gas and water vaporApril 27, 2010USEPA Steam Electric EGL Site Visit15WFGD Wastewater ManagementGMF Gypsum StackSize: ~30 acresDesigned to be closed in placeGroundwater monitoringPart of zero discharge GMFMajor functionsWW treatment during WFGD operationWFGD surge volumeConceptGypsum sluiced from WFGDSettled gypsum in active cell, decant water to reclaim pondClarified reclaim pond water returned to WFGDApril 27, 2010USEPA Steam Electric EGL Site Visit16WFGD WW OverviewApril 27, 2010USEPA Steam Electric EGL Site Visit17Gypsum Stack Liner Cross SectionApril 27, 2010USEPA Steam Electric EGL Site Visit18WFGD Wastewater ManagementGMF Reclaim PondSize: ~10 acresContributing flowsGypsum stack decantStormwater runoff from gypsum stackLandfill leachateGypsum stack leachateGroundwater monitoringPart of closed loop GMFApril 27, 2010USEPA Steam Electric EGL Site Visit19Bottom Ash Wastewater ManagementBegan operation in 2008Major componentsTwo Primary Settling BasinsSecondary Settling PondBasins: 12” clay, 60mil Geomembrane, 8” concreteBottom Ash Laydown AreaBottom ash (2.03MGD) and low-volumetreatment (1.20MGD)100% Beneficial use (on-site landfill alternate)April 27, 2010USEPA Steam Electric EGL Site Visit20Bottom Ash Wastewater ManagementBasin designSource water & dischargeSolids managementApril 27, 2010USEPA Steam Electric EGL Site Visit21Bottom Ash Basin Cross SectionApril 27, 2010USEPA Steam Electric EGL Site Visit22“Low-volume” Wastewater ManagementMajor ComponentsBoiler room sump (0.3MGD)Turbine room sump (0.3MGD)Water treatment room sump (0.6MGD)STP (0.004MGD)Treated in Bottom Ash Settling BasinApril 27, 2010USEPA Steam Electric EGL Site Visit23Landfill Wastewater ManagementStormwater runoffReservoir for treatmentLeachateDust controlZero discharge GMFApril 27, 2010USEPA Steam Electric EGL Site Visit24GMF Wastewater ManagementStormwater runoff design consideration12-week plant outageNo return to WFGDAssume max 12-week precipitation on record (30.93”)0.5PMP (16.25”) 24H storm event...and 900,000ft3of additional sediment/storageareaLeachateGypsum stack returned to GMFApril 27, 2010USEPA Steam Electric EGL Site Visit25Coal Pile Runoff WastewaterManagementCoal (and limestone) storageDitch collection systemReservoirApril 27, 2010USEPA Steam Electric EGL Site Visit26NPDES Permit IL0055620 Outfalls001 – Dam Seepage Collection System002 – Cooling Pond Overflow (el 565.0)003 – River Intake Screen Backwash004 – Cooling Pond Overflow (el 562.5)April 27, 2010USEPA Steam Electric EGL Site Visit27Outfall Location Map001 & 002003004April 27, 2010USEPA Steam Electric EGL Site Visit28Plant TourAir pollution control overview – ESP,SCR, FGDFGD Process OverviewGypsum Management Facility (GMF)LandfillApril 27, 2010USEPA Steam Electric EGL Site Visit29Duck Creek Power PlantSite Visit - SummaryComments and questionsAction Items