sr4+.""a3,ZUNITEDSTATES ENVIRONMENTALPROTECTIONAGENCY$=$ATLANTA REGION FEDERAL4CENTERe%oZ61 FORSYTH STREET4~PA&6<\ATLANTA,GEORGIA30303-8960OCT202011Ms.SheilaC.HolmanDirectorDivisionofAirQualityNorth Carolina DepartmentofEnvironment and NaturalResources1641 MailService CenterRaleigh,North Carolina27699-1641DearMs.Holman:ThankyouforsubmittingtheStateofNorthCarolina's201 1 annualambient air monitoring networkplan(Network Plan),dated July1,2011.TheNetworkPlanisrequiredby 40 CodeofFederalRegulations(CFR)558.10.TheNetworkPlan coverstheambientair monitoringnetworkfor theNorthCarolina Division ofAirQualityandits localagencies.TheU.S.EnvironmentalProtection Agency Region4understandsthattheNC-DAQ provided a 30-daypubliccomment periodanddidnotreceive any publiccomments.According to 40CFR§58.10(a)(2),sincepublic inspection and comment have already beensolicited,EPARegion 4isnotrequired toofferanothercomment period.Based uponour reviewoftheNetwork Plan,EPARegion4hasdetermined thattheplansatisfies theapplicablerequirementsof40CFRpart58.Therefore theNetwork Planisapproved.Thankyou forworkingwith us tomonitor airpollution and promotehealthy air qualityinNorthCarolinaandthenation.Ifyouhave any questionsorconcerns,please contact DougNeeleyat(404)562-9097orKatherine Snyder at (404)562-9840.GwendolynKeyes FlemingRegional AdministratorEnclosuresInternetAddress(URL)http://www.epagovABcvcled/Recvclable.PrintadwithVpnatahlnnilR~COAhkconmrrhr(DI-A-/anr:-..-n--.-.-..-.cc:Mr.DonnieRedmondSupervisorIV,NorthCarolinaDept.ofAirQualityMr.DonR.WillardDirector,MecklenburgCountyLandUseandEnvironmentalServices AgencyMr.WilliamM.Barnette, DirectorDirector,ForsythCountyEnvironmentalAffairsDepartmentMr.DavidBrigmanDirector, WesternNorthCarolinaRegionalAirQualityAgencyFY2011State ofNorthCarolinaAmbientAirMonitoringNetworkPlanU.S.EPARegion4Commentsand RecommendationsThisdocumentcontainsU.S.EPARegion4 commentsandrecommendations ontheStateofNorthCarolina's2011ambientair monitoringnetworkplan(Network Plan). Ambientairmonitoring rules,which include regulatoryrequirements thataddressnetwork plans,data certification,andminimummonitoring requirements,amongotherrequirements,arefoundin40CFRPart58.Minimummonitoring requirements for criteriapollutantsarelisted in40CFRPart 58, AppendixD.Minimummonitoring requirements donotexistfor carbonmonoxide(CO) unless required bytheestablishmentofaNationalCore(NCore)multi-pollutant monitoringstation,andlora state implementationplan.,However,newnationalambientair quality standards(NAAQS)were promulgatedin2010fornitrogendioxide(NO2)andsulfur dioxide(SOz)with minimum monitoring requirementseffective January1,2013.Minimum monitoringrequirements for nitrogen dioxide(NO2)willbeaddressedin the2012networkplans. Minimummonitoring requirementsarelistedin thisdocumentforozone(03),particulate matter lessthan2.5microns(PM~s),particulatematterlessthan10microns(PMlo),sulfurdioxide(SOz),and lead (Pb).Theminimum monitoringrequirements are basedonmetropolitanstatisticalarea (MSA)boundariesasdefinedbytheU.S.OfficeofManagement and Budget(OMB),July1,2009,population estimatesfiomtheU.S.CensusBureau, andhistoricalambientairmonitoringdata.OMBcurrentlydefines 15MSAsintheState ofNorthCarolina.TheseMSAsandtherespectiveJuly1,2009,population estimatesfiomtheU.S.CensusBureauareshowninTable1.Table1:MetropolitanStatisticalAreasandPopulationsMSA NamePopulationCharlotte-Gastonia-Concord,NC-SC1,745,524Virginia Beach-Norfolk-Newport News,VA-NC1,674,498Raleigh-Cary,NC1,125,827Greensboro-High Point, NC714,765Durham-Chapel Hill, NC50 1,228Winston-Salem,NC484,921Asheville, NC412,672Hickory-Lenoir-Morganton,NC365,364Fayetteville,NC360,355Wilmington,NC354,525Greenville,NC179,715Jacksonville,NC173,064Burlington,NC150,358Rocky Mount,NC146,536Goldsboro,NC113,811MinimumOzone MonitoringRequirements40CFR Part58,AppendixD,TableD-2Thenetwork describedin the2011NetworkPlanmeetstheminimumO3monitoring requirementsspecifiedby40 CFRPart58,AppendixD,TableD-2inallareas exceptfor the AshevilleandHickoryMSAs.TheAshevilleandHickoryMSAseachhavethe correct numberofrequiredozonemonitors(two), but onlyone ofthose is designated asaState andLocalAirMonitoring Station (SLAMS) andthesecond monitorisdesignatedas"other."Foramonitortocontribute to the minimum monitoringrequirement,it mustbeclassifiedasaSLAMSmonitorinEPA'sAirQuality System(AQS),thusthemonitor classifications shouldbeupdatedin AQS.Inaddition,asupplementalrequestto theNetworkPlan wassubmitted viaemailon August23,2011seekingtoshutdowntheFrying Pan monitor(AQSID:37-087-0035)2-3weeksprior-toOctober3 1.TheFrying Pan monitorisoperated yearroundby the NationalParkService (NPS)inGreat SmokyMountains National Park.TheNPSwantstoshutdown themonitorbecauseitneeds toreplace the-monitor'sshelter. Replacing the shelter needs to be done before winter weather in the mountainousarea makes the task too difficult. Getting thisworkdoneinOctober willhelp ensurethatthe monitorisoperationalby thebeginningofthe2012ozone monitoringseason.EPAconcurs that thisisnecessaryand any impact to data completeness during this time framewillbenotedappropriatelybyEPA.MinimumPMloMonitoringRequirements40CFRPart58,AppendixA,3.3.140CFRPart58,AppendixD,TableD-4TheStateofNorth Carolina's currentPMloprimarymonitoringnetworkmeets the minimumrequirements for all areas.AllPMlocollocationrequirementsfor manualmethodsfoundin40CFR Part58,AppendixA,3.3.1are currently beingmet.These include therequirement thatfifteen percentofeachnetworkofmanualPMlomethods (at leastonesite)mustbecollocated.MinimumPM2.5MonitoringRequirements40CFRPart58,AppendixA,3.2.540CFR Part58,AppendixD,TableD-5TheStateofNorth Carolina's currentPM2.5monitoringnetworkmeetstheminimumrequirementsfoundin40 CFRPart58,AppendixD,TableD-5forallMSAs.ManualPM2.5collocation requirementsarefoundin40CFRPart58,Appendix A,3.2.5.Theseinclude the requirementthatfifteen percentofeachnetworkofmanualPM2.5methods (atleastonesite) mustbecollocated.Themanualcollocationrequirements forPM2.5arecurrently being met in theNetworkPlan.PMz.5Continuous MonitoringRequirements40CFRPart58,AppendixD,4.7.2Regulatory requirements for continuousPM2.5monitoring requirethat"...State,orwhere appropriate,local agencies must operate continuousPM2.5analyzersequaltoat least one-half (round up)theminimumrequiredsites listedinTableD-5ofthisappendix.Atleastonerequiredcontinuous analyzerineachMSAmustbecollocated withone oftherequiredFRM/FEM/ARM[FederalReference'Method/FederalEquivalentMethod/ApprovedRegionalMethod]monitors,unlkssatleastoneoftherequiredFRMIFEWARMmonitorsisitselfacontinuousFEMorARMmonitor in which casenocollocation requirementapplies."TheseminimumcontinuousPM2.5monitoring requirements arecurrentlymetinthe-alloftheMSAsin theState. Also,thecontinuousPM2.5collocationrequirementsare currently met inall MSAs. Therefore,the continuousPM2.5monitoringnetworkdescribedinthe2011 NetworkPlan meets all of the design criteriaof40CFRPart58.PM2.5Background and Transport Sites40CFRPart58,AppendixD,4.7.340CFRPart58,AppendixD,4.7.3requires that"eachStateshall installandoperateatleastonePM2.5siteto monitorfor regionalbackgroundandatleast onePM2.5sitetomonitorfor regional transport."The2011Network PlanidentifiessevenPM2.5.sitesasregionaltransportsitesthat include:Mendenhall(AQSID:37-081-0013), CherryGrove (AQSID:37-033-0001),SpringfieldRoad(AQSID:37-065-0004),Kenansville(AQSID:37-061-0002),Boone(AQSID:37-189-0003), Candor (AQSID:37-123-0001),andJamesville(AQSID:37-1 17-0001).TheNetworkPlan identifies three regional transportsitesforPM2.5identifiedas:Cherry Grove(AQSID:37-033-0001),Jamesville(AQSID:37-117-0001),andBryson City (AQSID:37-173-0002).Therefore,NC-DAQhassatisfiedtherequirementsof40CFRPart58forbackground andtransport sites.LeadMonitoring Requirements40CFRPart58,kppendixD,4.5EPArecentlyrevisedthemonitoringrequirements forPbfound at40 CFRPart 58,AppendixD,Section4.5(see75 Federal Register81126).These revisionsreducedthe emissionsthresholdforfacilitiesnear whichsourceorientedPbmonitoringisrequired from1.0tons per year(tpy)to0.5tpy.Therule alsoremoved population-basedmonitoring requirements forPband replaced themwith arequirement tomonitor for PbaturbanNCoresites.40CFRPart58, AppendixD,4.5requires that"Ataminimum,theremust be onesource-orientedSLAMS[stateandlocal air monitoring station] site locatedto measure the maximumPbconcentrationinambientairresulting fromeach non-airportPbsourcewhichemits0.50ormoretonsperyear andfromeach airport whichemits1.0ormore tonsperyear..."Initsnetworkplan,NorthCarolina hasrequested thatEPAgrantawaiverofsource-oriented Pbmonitoringrequirementsfortwosources. Section4.5(a)(ii)ofAppendixDto40CFRPart58providesthefollowing provisions for awaiver ofthePbmonitoringrequirements:"(ii)TheRegionalAdministratormaywaivetherequirementinparagraph4.5(a)formonitoringnearPbsourcesiftheStateor, where appropriate, localagencycandemonstrate the Pb sourcewillnot contributetoamaximumPbconcentrationinambientairinexcessof50%oftheNAAQS(basedonhistoricalmonitoring data, modeling,orothermeans).Thewaiver mustberenewedonce every 5yearsaspartofthenetwork assessment required under58.1O(d)."North Carolinahassubmitted airmodelingindicatingthatthe following sourceswillnotcontribute toamaximumPbconcentrationintheambientairin excessof50%theNAAQS:Blue Ridge PaperProducts,Inc.Canton,North CarolinaSaintGobainContainersWilson, NorthCarolinaEPAhas reviewedthisinformationandconcursthatthePbemissions fromeachofthesesourceswillnot contributetoamaximumPbconcentration intheambientairinexcess of50%of theNAAQS.Therefore,EPAisgrantingthewaiversof thesource-orientedambientairmonitoring requirementsatthesesources.Thewaivers mustberenewedonceevery five yearsaspartofthe network assessmentrequiredunder40CFR$58.1O(d).North CarolinahasalsorequestedthatEPAconsiderrevisedemissions data relatedtosource-orientedPb monitoring requirements. North Carolinahassubmitted information indicating that theactualPbemissionsfromthe following sources arebelow0.50tpy:Duke EnergyCarolinas,LLCBelewsCreek SteamStationBelews Creek,NCProgress EnergyRoxboro PlantSemora,NCDuke EnergyCarolinas,LLCRoyalDevelopment CoMarshallSteam StationHigh Point,NCTerrell,NCU.S.ArmyFortBraggDuke EnergyCarolinas,LLCCumberlandCounty,NCAllen SteamStationBelmont,NCU.S.Marine Corps CampLejeuneOnslowCounty,NCEPA hasreviewedthisinformationandconcurs thattheactualPbemissionsfromthese sources arebelow0.50tpy.Therefore,ambientair monitoringisnot required atthese sources. Populationorientedmonitoring isstillrequiredaturban NCoresitesbeginningonDecember27,2011. Basedon the2011NetworkPlan,North CarolinawillsatisfLtheminimummonitoring requirementsforPb.'SulfurDioxide Monitoring Requirements40CFRPart58,AppendixD,4.4Ambientair monitoringnetworkdesign criteria forSO2arefoundin Section4.4ofAppendix Dto40CFRPart58.Thissection requiresthat"Thepopulationweightedemissionsindex(PWEI)shall becalculatedbyStatesforeachcorebasedstatistical area(CBSA)."Asa result, theSO2monitoringsite(s)requiredineach CBSA willsatisfyminimummonitoring requirementsifthemonitor(s)is sitedwithintheboundaries oftheparentCBSA andis oneof thefollowingsitetypes:population exposure,maximum concentration,source-oriented,generalbackground, or regional transport. AnSO2monitorata NCore stationmaysatisfyminimummonitoring requirementsifthatmonitorislocated within aCBSAwith minimallyrequired monitors consistent with AppendixD,4.4.TheSOznetworkisto beoperationalbeginningJanuary1,2013.TheCharlotte-Gastonia-ConcordCBSAisrequiredtohave a totaloftwoSO2monitors. Currently,there isonly oneoperatingSO2monitorin theCBSA,located attheGaringersite(AQSID:37-1 19-0041).Inane-mail datedSeptember20,2011, South CarolinaDepartmentofHealthandEnvironmentalControl committedtoestablishing aSO2monitorattheYorksite(AQSID:45-091-0006)toassist in meeting the minimummonitoring requirementsforthisCBSA.OncetheSO2monitorattheYorkmonitoringsiteinSouthCarolina becomes operational,the Charlotte-Gastonia-Concord CBSA will meettheminimummonitoring requirements under 40CFR Part58.Similarly, oncetheadditionalSO2monitoratMendenhall(AQSID:37-08 1-0013)becomes operational,theGreensboro-HighPointCBSAwill meettheminimum monitoringrequirementsunder40CFRPart58.All theotherCBSAsmeettheminimummonitoring requirementsbasedon theinformationprovidedin the2011Network Plan.AirQualityIndex(AQI)Reporting40CFR858.50AQIreportingisrequiredinMSAs withpopulations over350,000.Thereare10 MSAsinthe State ofNorth Carolinarequired toreportanAQI:Charlotte-Gasonia-Concord,VirginiaBeach-NorfolkNewportNews,Raleigh-Cary,Greensboro-High Point, Durham-Chapel Hill, Winston-Salem,Asheville,Hickory-Lenoir-Morganton,Fayetteville, and Wilmington.NC-DAQmeetstheseAQIreportingrequirements.Monitoring Network ChangesProposedbyNC-DAQNC-DAQhasproposedseveral monitoringnetwork changesin its2011NetworkPlan.Monitorsproposedfor discontinuation aresummarizedinTable2.Table2:Monitors proposedfordiscontinuationAocationchangeAQSIDPollutantTypeComments37-183-001 8CarbonMonoxideSLAMSWillusetheFRMCO monitoratthe MillbrooksitetofulfilltheSIPrequirements37- 173-0002pM2.5SLAMS-Regional Monitor willbeshut downattransportcompletion of20monthBAMstudy(512011)EPAhasreviewed theserequests for discontinuationormonitor relocationand determinedthatalloftherequested monitors,inTable2,meet the requirementsof40CFR§58.14(~)(6)for monitordiscontinuation.Theminimummonitoring requirementsforPM2.5andO3found inAppendix Dto40CFR Part58willcontinuetobemetforthe respectiveMSAsafterthesemonitors are discontinued.NC-DAQalsorequestedtochangethemonitoringfrequericyatAQSIDS37-081-0013,37-071-0016,37-051-0009,and 37-001-0001 to1 in 6 day forPM2.5sampling. Atthisproposedfkequency,themonitorswill meetthePM2.5operating schedulerequirements under40CFR$58.12(d)(l)(i).Therefore,EPA approves the changeinmonitoringfrequency at thesesites.NationalCore (NCore)MonitoringNetworkAmbientairmonitoring networkcriteriafor NCoresitesarefoundin Section 3ofAppendixDto 40CFR Part58.NC-DAQhas designatedtwoNCoresitesin the2011NetworkPlan.Thefirstsite(AQSID37-183-0014)islocated at the East Millbrook Middle Schoolsite inRaleigh,NC.Thesecondsite(AQSID37-1 19-0041)islocatedattheGaringersite inCharlotte,NCandisoperated bytheMecklenburg CountyLandUseandEnvironmental Services Agency.OfficialEPAapprovalwasgranted for these siteson October30,2009. The2011NetworkPlanmeetsthe minimummonitoringrequirementsfor NCoresites.Air QualitySystem(AQS)Duringthereviewofthe2011NetworkPlan,therewere afewdiscrepancies identified betweeninformation intheNetworkPlan andin AQS.The State isresponsible for updating monitor typeclassifications inAQS. Based onlistingsofmonitor types in theNetwork Plan, NC-DAQhas severalmonitorsthatarelistedas"other."EPAencourages theStatetobemorespecific intheir monitor typesinAQS.Monitors thatarelisted as"other"willbetreatedasaSLAMSmonitor for regulatoryevaluations.Fora monitortocounttowardthe minimum monitoring requirement(e.g.ozonerequirements above), it mustbeclassifiedasaSLAMSmonitor inAQS,thus themonitor classificationsshouldbe updatedinAQS(WagginTrailAQSID:37-003-0004).Also, theState should verifythatmonitor typesinAQSmatch thoseintheNetwork Plan.Forexample,the ozone monitoratWaynesville(AQSID37-087-0004)islistedas a SLAMS monitor in theNetworkPlan, butas"other"inAQS.Inaddition, therearediscrepanciesinmonitor type inAQSand theNetwork Planforthefollowing sites, AQSIDS:3 1-159-0021-42101-1,37-159-002 1-4420 1-1,and37-l79-OO3-#2Ol-l.In addition,theStateshould verifythePM2.5backgroundmonitor designations inAQS.Therearetwosites inAQSdesignated asPM2.5backgroundsitesthatarenotdesignatedinthenetworkplan asbackgroundsites.These sitesinclude:Pittsboro(AQSID:37-037-0004) andWestJohnston(AQSID:37-101-0002).