OS?4UNITEDSTATESENVIRONMENTALPROTECTIONAGENCY4REGIONIX1PRO175HawthorneStreetSanFrancisco,CA94105-3901JUN172014Mr.MahmoodHossain,Chief,MonitoringandTechnicalServicesSanDiegoCountyAirPollutionControlDistrict10124OldGroveRoadSanDiego,California92131-1640DearMr.Hossain:Inyourpreviousmonitoringannualnetworkplan,SanDiegoCountyAirPollutionControlDistrict(SDCAPCD)requestedEPA’sapprovaltoconsiderthe2010-2012PM2.5datafromyourcontinuousFEMmonitorsatthefollowingsitesasnoteligibleforcomparisontotheNAAQS:ElCajon(AQSII)06-073-0003),SanDiego-Downtown(AQSID06-073-1010),Escondido(AQSID06-073-1002),Alpine(AQSID06-073-0006)andCampPendleton(AQSID06-073-1008).Yourmostrecentmonitoringannualnetworkplanupdatesthisrequesttoinclude2013datafromthesamemonitors.ThisletterisinresponsetoyourrequestsandapprovesthemonitorslistedbelowforthespecifieddatesasnoteligibleforcomparisontotheNAAQS(i.e.,providesawaiverforNAAQScomparability).Accordingto40CFR58.11(e),inordertobeconsiderednoteligibleforcomparisontotheNAAQS,continuousFEMPM25datamustbeshowntonotmeetthecriteriain40CFR53TableC-4.Thesecriteriadescribethemaximumallowablemultiplicativeandadditivebiasbetweenafilter-basedFRMPM2.5monitorandaClassificontinuousFEMPM2.5monitoroperatingatthesamesite.EPAbaseditsevaluationonthecriteriain40CFR53asdescribedbyourmemodatedApril20,2013anditsattacheddocumenttitled“InstructionsandTem?lateforRequestingthatdatafromPM2.5ContinuousFEMsarenotcomparedtotheNAAQS.”Wereviewedyourrequestfor2010-2012data,andwellasyourupdatedrequestfor2011-2013data.Afterreviewingtheinformationinyourrequests,wehavedeterminedthatthefollowingmonitorsdonotmeetthebiascriteriain53andareapprovedasnoteligibleforcomparisontotheNAAQSforthenotedtimeperiods:‘ThismemoandtoolsusedforcomparingFRMandcontinuousFEMdataarefoundatEPA’swebsite:htt:j/www.epa.gov/ttnamtii/contront.htm.PrintedonRecycledPaperSiteNameAQSID-ParameterCode-POCBeginDateEndDateElCajon06-073-0003-88101-33/4/201112/31/2013Escondido06-073-1002-88101-404/08/201012/31/2013Escondido06-073-1002-88101-31/1/201012/31/2012SanDiego-Downtown06-073-1010-88101-311/1/201112/31/2013OneofthecontinuousFEMPM2.5monitorsatEscondido,POC3,doesmeetthecriteriaforbiasforthedatain2011-2013,andthereforethe2013dataareconsideredcomparabletotheNAAQS.Likewise,sincethereisvariabilityinthecomparabilitybetweenthefilter-basedandcontinuousmonitorsthroughoutyournetwork,wecannotapproveawaiverfromNAAQScomparabilityforthemonitorsatAlpineandCampPendletonwithoutcollocatedfilter-basedFRMdataasthebasisforsucharequest.However,sinceAlpineandCampPendletonstartedoperatinginJuly2012andNovember2011,respectively,theyhavenotcollectedenoughdatatocalculateadesignvaluethatisvalidforcomparisontotheNAAQSatthistime.YourrequeststatedthatyouconsiderthecontinuousPM2.5dataofsufficientqualitytoreporttotheAQI,andwillbesubmittingthedatatoAIRN0w,soyoumaynowre-loadthedatafromthemonitorsanddatesinthetableabovetoAQSundertheparametercode88502.Ifyouhaveanyquestionsregardingthisletterortheenclosure,pleasefeelfreetocontactmeat(415)947-4534,orKateHoagofmystaffat(415)972-3970.Sincerely,MeredithKurpius,ManagerAirQualityAnalysisOfficeEnclosure:A.EPAEvaluationoftheRequestforExclusionofPM2.5ContinuousFEMDatacc:DavidShina,SDCAPCDSylviaVanderspek,CARB

# A. EPA Evaluation of the Request for Exclusion of PM 2

. 5 Continuous FEM Data 1

1 

# Data from 2010-2013 evaluated here was generated on May 12, 2014 using the EPA PM 2

. 5 continuous monitor comparability

assessment tool found at the website: http://www.epa.gov/airguality/airdata/ad rep frmvfem.html. A technical note describing the

tool is located at http://www.epa.gov/ttnamtjl/fjles/arnbjent/pm2S/comparabjljtyassessmenttool.pdf.

# 2011-2013

Continuous! PM. 5 PM 5 Site Name Cont Method FRM Slope Intercept Meets bias I Correlation Site ID Cont. Cont End 

# / City POC Description Sampler pairs (m) (y) requirement I (r) Begin Date Date

per season



# Sites with PM 25 continuous FEMs that are collocated with FRM5:

Winter

= 

# 63

MetOne BAM Spring

= 

# 86

El Cajon 06-073-0003 2 3/1/2011 12/31/2013 Summer

= 

# 93 1.13 1.98 No 0.90 1020 (170)

Fall =88

- 

# Total=330

Winter

= 

# 122

San Diego- MetOne BAM Spring

= 

# 146

06-073-1010 2 11/1/2011 12/31/2013 Summer

= 

# 155 1.08 1.16 No 0.93 Beardsley 1020 (170)

FaIl

= 

# 199

Total

= 

# 622

Winter

= 

# 84

MetOne BAM Spring

= 

# 89

Escondido 06-073-1002 3 1/1/2011 12/31/2013 Summer

= 

# 80 1.10 0.35 Yes 0.96 1020 (170)

FaIl

= 

# 87

Total

= 

# 340

Winter

= 

# 84

Escondido 06-073-1002 MetOne BAM Spring =92

4 1/1/2011 12/31/2013 Summer

= 

# 81 1.14 1.91 No 0.92 1020 (170)

FaIl

= 

# 84

Total= 341



# Sites with PM 2

. 5 continuous FEMs that are not collocated with FRMs:

MetOne BAM Alpine 06-073-0006 1 7/1/2012 12/31/2013 1020 (170)

Camp MetOne BAM 06-073-1008 3 11/9/11 12/31/2013 Pendleton 1020 (170)