RECEIVEDJACKA.MARKELLGOVERNORSTATEOFDELAWAREOFFICEOFTHEGOVERNORTATNALLBUILDING,SECONDFLOORWILLIAMPENNSTREET,DOVER,DE19901JAN192011EPA.REGIONIII‘EOFREGIONALADMIN!STPTOEPH0NF:302-744-4101F\\:302-739-2775January13,2011Mr.ShawnM.Garvin(3RAOO)RegionalAdministratorU.S.EnvironmentalProtectionAgencyRegionIII1650ArchStreetPhiladelphia,Pennsylvania19103-2029cE\fEDiUj\P3ORECEIVEDJAN202011DiviiDl16L;OF(3APOO)DearAdministratorGarvin:OnJanuary22,2010,theU.S.EnvironmentalProtectionAgency(EPA)strengthenedtheNationalAmbientAirQualityStandards(NAAQS)fornitrogendioxide(NO2)byaddinganew1-hourprimarystandardof100partsperbillion(ppb)(3-yearaverageofthe95thpercentiledailymaximum1-hourconcentration).Section107(d)oftheCleanAirAct(CAA)requirestheGovernorofeachStatetosubmittotheEPAalistofallareas(orportionsthereof)intheState,designatingeachasnonattainment,attainment,orunclassifiable.ThisletterfulfillsDelaware’sobligationsunderSection107(d)oftheCAA.AreaDescriptionandMonitoringDataDelawareiscomposedofthreecounties,namelyNewCastle,KentandSussex,layingfromnorthtosouth.ThenorthernportionofNewCastleCountyliesabovetheChesapeakeandDelawareCanal,awaterwaythatconnectstheChesapeakeBaywiththeDelawareBay.ThispartofNewCastleCountyismoremetropolitanandindustrializedthantheremainderofDelaware.TheremainderofDelawareliessouthoftheChesapeakeandDelawareCanal,andcomprisesthesouthernportionofNewCastleCounty,andallofKentandSussexCounties.DelawarecurrentlymonitorsNO2atitsmonitoringsitenearMartinLutherKingBoulevard,whichislocatedinthecityofWilmington(NewCastleCounty).ThemeasuredambientNO2concentrationsfor2007through2009atthismonitorareshowninthetablebelow.NO2Concentration(ppb)98thPercentileDaily1stmax1-hour2rn1max1-hourMaximum1-hourYearConcentrationConcentrationConcentration20077573-642008149756820096862543-yearaverageof98thPercentik62DailyMaximum1-hourConcentratiorMr. Shawn

M. Garvin (3RAOO) U.

S. Environmental

Protection

Agency January

13, 2011 Page Two This monitoring

data indicates

that NO 2 concentrations

in Delaware’s

air are well below

the

100 ppb NAAQS. However, Delaware

notes

that

its NO 2 monitor

has experienced significant

down

time due

to repair,

and data completeness

is somewhat

low (i.e.,

less than
75%

for 2007

and 2009). Along

with

the new hourly

NO 2 NAAQS,

the EPA

has established

new near-road monitoring network requirements

that

are anticipated

to
go into effect January

2013. Delaware

does

not operate

a near-roadway

monitor,

and understands

that

it will
not

be required

to perform near-roadway
monitoring under
these

new requirements.

With

this understanding,

Delaware
believes

its current

NO 2 monitoring network

is adequate

and complete. Attainment/Nonattainment

Recommendation Because Delaware

does

not have

the required

75%

data completeness

from

its existing

NO 2 monitoring

network,

all three counties

in Delaware

should

be designated

as unclassifiable

for
the new

1- hour
NO 2 NAAQS.

Despite

this unclassifiable recommendation,

we believe

the data

we

do have strongly indicates

that

the

air quality

in Delaware currently

is

in attainment

for
the new NO 2 standard. Delaware anticipates requesting re-designation

to attainment

once 3-years

of complete

data

are obtained. Thank

you

for your consideration

of the above recommendations.

If you have

any questions concerning

this submittal

or would

like

to discuss

it further,

please contact

Mr.

Au Mirzakhaliii,

the Director

of our Division

of Air Quality,

at (302)739-9402. Sincerely, Jack

A. Markell Governor pc:
Diana Esher,

EPA, Region

III Coffin

P. O’Mara, DNREC Dave Small, DNREC Ali Mirzakhaliii,

DNREC