1&,WSQ,&$a*%UNITEDSTATESENVIRONMENTALPROTECTIONAGENCY3~:ATLANTA REGION FEDERAL4CENTER0t5PRo~"'861FORSYTH STREETATLANTA.GEORGIA30303-8960SEP232010MyraReece,ChiefBureauofAirQuality ControlSouthCarolinaDepartmentofHealth and EnvironmentalControl2600BullStreetColumbia,SouthCarolina 29201DearMs.Reece:Thankyouforsubmitting theStateofSouth Carolina's 2010annualambient airmonitoringnetwork plan (NetworkPlan)and five-year ambientairmonitoringnetworkassessment(Network Assessment),dated July1,2010. TheNetworkPlanand NetworkAssessmentarerequiredby40CodeofFederal Regulations(CFR)558.10.TheEnvironmentalProtectionAgency (EPA) Region4understands thattheSouthCarolina DepartmentofHealth andEnvironmentalControl (DHEC) providedthe public a30-dayreview period.Theonlycomment receivedwasfromthe National ParkServicewhichexpressedappreciationtoDHECforthetimeandexpensesit putinto operating amonitoringsiteattheCowpensNational Battlefield.Baseduponourreviewofthe NetworkPlanandNetworkAssessment, EPARegion 4hasdeterminedthatthe documentssatisfy the applicablerequirementsof40CFRPart58.Also, theStatewasfoundtohave adequately consideredthe additional factors specifiedbyEPA Region 4in conducting theNetworkAssessment.TheNetworkPlanisapproved.Commentsandrecommendations onbothdocumentsareenclosed.Thankyouforyour workwithustomonitorairpollution and promotehealthy airquality-inSouthCarolinaand the nation.Ifyouhaveanyquestions or concerns,please contact DougNeeleyat(404)562-9097orDavidMcNealat(404)562-9102.Sincerely,/I%&Gwendolyn KeyesFlemingRegionalAdministratorEnclosureInternetAddress(URL)http://www.epa.govRecycled/Recyclable*PrintedwlhVegetableOnBasedInksonRecydedPaper(Mlnbnum30%Postconsumer)cc:Mr.RobertBrownDivisionDirector,AirPlanningDevelopmentandOutreach,SCDHECMr.ScottReynoldsDirector,DivisionofAir QualityAnalysis,SCDHECMr.ThomasFlynn,Manager,Air DataAnalysisandSupportSection,SCDHECFY2010StateofSouthCarolinaAmbientAirMonitoringNetworkPlanU.S.EPARegion4CommentsandRecommendationsThis documentcontainsU.S.EPARegion4commentsandrecommendationsontheStateofSouthCarolina's 2010 ambientairmonitoringnetworkplan (NetworkPlan). Ambientairmonitoring rules, whichincluderegulatory requirementsthataddress network plans, datacertification,and minimummonitoringrequirements, amongotherrequirements,arefoundin40CFRPart58.Minimum monitoring requirementsforcriteria pollutants are listedin 40CFRPart58, AppendixD.Minimum monitoring requirements do not exist for carbon monoxide(CO)unlessrequiredby theestablishmentofaNational Core(NCore)multipollutant monitoringstation,and/orastateimplementationplan.However,newnational ambientairquality standards(NAAQS)were promulgatedthisyearfor nitrogen dioxide(N@)andsulfur dioxide(SO2)withminimummonitoring requirements effective January1,2013.Minimum monitoringrequirementsarelistedfor ozone(03),particulatematterlessthan2.5microns(PM2.5),particulate matterlessthan10microns(PMlo),andlead(Pb).Theminimum monitoring requirementsarebasedonmetropolitan statisticalarea(MSA)boundariesasdefinedbytheU.S.OfficeofManagementandBudget(OMB),July1,2009,population estimatesfromtheU.S.Census Bureauandhistoricalambientairmonitoringdata.OMBcurrentlydefines10MSAsintheStateofSouth Carolina. TheseMSAsand therespectiveJuly1,2009,population estimatesfromtheU.S.CensusBureauareshowninTable1.Table1:MetropolitanStatisticalAreasandPopulationsMSA NamePopulationCharlotte-Gastonia-AndersonNC-SC1,745,524Columbia,SC744,730Charleston-North Charleston-Surnmerville,SC659,191Greenville-Mauldin-Easley,SC639,617Augusta-RichmondCouuty,GA-SC539,154Spartanburg,SC286,822MyrtleBeach-Conway-NorthMyrtleBeach,SC263,868Florence,SC200,653Anderson,SC184,901,Sumter,SC104,495Minimum OzoneMonitoringRequirements40CFR part58,appendixD,tableD-2Region4has determined that theozonemonitoring networkoutlinedintheNetworkPlanmeets theminimumrequirementsfoundin 40CFR part 58, appendixD,tableD-2for allMSAs.MinimumPMloMonitoring Requirements40CFRpart 58, appendixA,3.3.140CFRpart 58, appendixD,tableD-4Region4hasdeterminedthat thePMlomonitoring networkoutlinedintheNetworkPlanmeetsorexceedstheminimumrequirements foundin40CFRpart 58, appendixD,tableD-4forallMSAs. Also,allmanualPMlocollocationrequirementsaremet.MinimumPM2jMonitoring Requirements40CFRpart58, appendixA,3.2540CFRpart58,appendixD,tableD-5'Region4has determined that thePM2.5monitoring networkoutlined in theNetworkPlanmeetsorexceeds theminimumrequirements foundin40CFRpart 58,appendixD,tableD-5forallMSAs.Also,allPM2.5collocationrequirementsaremet.PMnsContinuousMonitoringRequirements40CFRpart 58,appendixD, 4.7.2Regulatory requirementsforcontinuousPM25monitoringrequirethat"...State,orwhereappropriate, localagencies mustoperate continuousanalyzers equaltoatleastone-half(round up) theminimumrequiredsiteslistedinTableD-5ofthisappendix. Atleastonerequiredcontinuousanalyzer in eachMSAmustbecollocated withoneofthe required FederalReferenceMethod(FRM)/FederalEquivalent, Method(FEM)/ApprovedRegional Method(ARM)monitors, unless atleastoneoftherequiredFRM/FEM/ARMmonitorsisitself acontinuousFEMorARMmonitorinwhichcasenocollocationrequirementapplies."Afterreviewoftheoutlined networkRegion4hasdeterminedthat theproposedPM25continuousmonitoringnetworkmeetsorexceeds theminimumrequirementsinthealloftheMSAsin theState.Also,thecontinuousPM2.Scollocationrequirementsaremetin allMSAs.PM2jBackgroundandTransportSites40CFRpart58, appendixD,4.7340CFR part 58,appendixD,4.7.3requires that"EachStateshall installandoperateatleastonePM2.Ssitetomonitorforregional backgroundlevelsandatleast onePM2.ssite tomonitorforregionaltransport."TheNetworkPlanidentifiesAshton(AQSID45-029-0002)inColletonCountyasa regional backgroundsiteandChesterfield(AQSID45-025-0001)inChesterfieldCountyasa regionaltransportsite. Therefore, DHEC hassatisfied therequirementsof40CFRpart58forregional background andtransportsites.PbMonitoringRequirements40CFRpart 58,appendixD,4.5DHEC'sNetworkPlanidentifiesthe followingPbmonitoringsitesthat were addedtothenetworktosatisfypopulation based monitoring requirementsinpart58, appendixD:WANameAQSIDColumbia,SC45-079-0019Charleston-NorthCharleston-Surnmerville,SC45-019-0003Greenville-Mauldim-Easley,SC45-045-0015January1,2011, isthedeadlineforoperationofthesemonitors, butEPAhasproposedchangesto itsPbmonitoringrequirements.Undertheseproposed changes,population-basedmonitorswillnotberequiredandEPAhasadvisedstatesnottoexpend anyresources planningor installingthem.TheNetworkPlan indicatesthatmonitoringat the abovesitesmaybeterminated,pendingthepromulgationoftheproposed changestoEPA's Pbmonitoringrequirements.Inaddition,theNetworkPlan indicates thatanew Pbmonitorwillbeaddedto theParklane(AQSID45-079-0007)NCoresiteinanticipationofthechangestothePbrequirementsin40CFRpart58.Baseduponourreview,allofthePb monitoringprovisions in theNetworkPlanareacceptable.AirQualityIndex(AQI)Reporting40CFR958.50AQIreporting is requiredinMSAswith populations over350,000.TherearethreeMSAsinthe StateofSouth CarolinarequiredtoreportanAQI:Greenville-Spartanburg,Columbia,andCharleston-NorthCharleston.TheNetworkPI*onpage3indicates thatthedailyAQIfortheseareasisavailableonEPA'sAIRNowwebsite.ThissatisfiestheAQIreporting requirements.MonitoringNetwork ChangesProposedbyDHECDHEChasproposedseveralmonitoring network changesintheNetworkPlanwhich aresummarizedinTable3.---JAQSIDPollutantComments45-007-0004PMzJSPMSitediscontinued45-045916P&SPMAdditiontoexistingsite45-083-0010PMzJSLAMSMovewithinMSA45-043-0006PMIOSPMSitediscontinued45-043-0012PMtoSPMSitediscontinued45-019-xxxxpMz.5SPMNewsite45-O~PXXXXBlackcarbonNon-regulatoryNew site45-019-0049pM2.5SLAMSMovewithinMSA45-019-0049SpeciatedPMloSPMSitetobediscontinued45-041-0002pM2.5SLAMSMovewithinMSATheStateofSouth CarolinahasproposedtomovethreeofitsPM2.5monitoringsites.Onemove wouldinvolve relocatingamonitorintheSpartanburgMSAfromtheWestview(AQSID45-083-0010)sitetotheT.K.Gregg(AQSID45-083-0011) siteandanothermovewouldinvolve relocatingamonitorinthe FlorenceMSAfrom theH.L.SneedMiddleSchool(AQSID45-041-0002)sitetotheWilliams(AQSID45-041-0003)site.AccordingtotheNetworkPlan,theWestviewandtheH.L.Sneed MiddleSchoolsitesneedto berelokatedbecause they do not havesufficient spacetoaccommodatepart58requirementsforthecollocationofcontinuousPM2smonitors.TheNetworkPlan indicatesthatthetwonewproposedsitesmeetallprobesitingand networkdesign requirements in40CFRpart 58,appendicesDandE.Based uponourreviewofdata collected simultaneouslyfor oneyearateachpairofsites,the proposedrelocationofbothPM2smonitoringsitesisacceptable.Theproposal tomovethePM2.5monitoringsiteat the Charleston PublicWorks (AQSID45-019-0049)sitehas beenmadependingidentificationofasuitablereplacementsiteandcollectionofdata demonstratingthattheproposedsiteis representativeofthecurrent site.EPAwillmakeadeterminationregarding the acceptabilityofthismoveonceDHECprovidestheresultsofsimultaneousmonitoringatthe existingsiteandtheproposedsite.Sincenoneofthe specialpurpose monitoringsitesthatDHECproposestoshutdown areusedformeetingtheminimummonitoring requirementsinappendixDof40CFRpart 58,theproposaltodiscontinue thesemonitorsisacceptable.NationalCore(NCore)MonitoringNetworkDHECproposedParklane(AQSID45-079-00047)andChesterfield(AQSID45-025-0001)as NCoresitesinits2010Network Plan.EPA'sOfficeofAirQuality PlanningandStandardsgranted approvalofthesitesinaletterdated October30,2009.Followingapproval,DHECdecided not tooperate Chesterfieldas anNCoresite.However,DHECwillcontinuetooperate regional transport,regional background,andairtoxicsmonitorsatthis site.AccordingtotheNetworkPlan,monitorsforall requiredNCorespecies areexpectedtobeoperational attheParklanesitebytheJanuary1,2011,deadline. The only change identifiedforthe NCoresiteintheNetworkPlan is the additionofaPbmonitor.This monitorisbeingaddedin anticipationofrevisionstothePbmonitoringrequirementsinpart58.Five-Year AmbientAirMonitoringNetwork AssessmentInadditionto theNetworkPlan,DHECsubmittedafive-yearNetwork.Assessment.Thisassessmentisrequired underprovisionsin40CFR§58.10(d)andDHECsubmitteditbytheJulyl,2010,deadline.Ataminimum,theNetworkAssessmentmustconsiderwhetherthemonitoring network meetsthe objectives outlinedinappendixDto40CFRpart58,whethernewsitesare needed, whetherexistingsitescanbeterminatedbecausethey arenolonger needed,andwhethernewtechnologies are appropriateforincorporation into theambientairmonitoringnetwork.Theassessmentmustalsoconsider theabilityofthe existingand proposedsitestosupportairquality characterizationforareaswithrelativelyhighpopulationsofsusceptibleindividuals(e.g.,childrenwithasthma)andforanysitesproposedfordiscontinuation, the effectondatausers otherthantheagencyitself,suchas nearbystates ortribesorhealth effects studies.ForPM2.5,theassessmentmustalsospeclfyneeded changestopopulation-oriented sites.Region.4requiredits stateandlocal agencies toconsiderthefollowing additionalfactorsintheirnetwork assessments:1.Statewideamdloca11level population statistics.2.Statewideambientairmonitoringnetworkpollutant trendsover thepast fiveyears.3.Networksuitability tomeasure the appropriate spatial scaleofrepresentativenessforselected pollutants.4.Monitoringdataspatial redundancyorgaps that need to beeliminated.5.Programmatic trendsorshiftsinemphasisorfimdingthat lead towarddifferent dataneeds.DHEC evaluateditsexistingmonitoringnetworkusing toolsprovidedbyEPAand theassessment explained thatthese toolswork bestforhigherdensity networks withwide spatialdistribution. BecausetheState'sozoneandPM25networks havethelargestnumberofmonitorsandarethemostwidelydistributed, the networksforthese pollutants received greateremphasisin the Network Assessment. Using the EPA toolsanda weighting systemthatconsiders anumberoffactors, DHECrankedits existingmonitoringsites inorderofimportance.Theweighting system assigned greater importanceto ambientconcentration levels, thelikelihoodof,national ambientair qualitystandard (NAAQS)violations, andthe populationofindividualseitherlessthan19ormorethan64yearsofage. Althoughthese factors receivedthehighestweighting,DHEG'sanalysisalso consideredtheareaservedbythemonitor, pollutantemissionlevels,population changes, the numberofpeople livingbelowthe poverty level, the lengthoftime a monitorhasbeeninservice,andthenumber of monitors atthe site.Inadditiontorankingiheimportanceofit existingmonitors, DHECidentified areaswhereadditional monitors would providethe most value.The assessment alsonotes,that duetoEPA'sreviewofmanyNAAQSandtheirassociated monitoringrequirements,it isnotfeasibletomakesignificant changes tothe State'sambientair monitoringnetwork atthistime. Anotherissuediscussedin theNetworkAssessmentistheneedforbetter evaluation toolsthat could bemadeavailablenowforuse inthe annual planningprocess. According totheassessment,thiswouldhelpavoidduplicationofeffortasDHECprepares for the nextfive-year assessmentwhichwill be dueonJuly1,2015.