RECEIVED, 

# f 2 ci MAR

1 4 20t)8STATEOFDELAWARE

EPA. REGION

III DEPARTM

ENT OF NATURAL RESOURCES FICEOFREG)NALAI)MINISTRATOR AND ENVIRONMENTAL CONTROLOFFICEOFTHE89KINGSHIGHWAYPHoNE: (302) 739-9000SECRETARYDOVER,DELAWARE
19901

FAx; (302) 739-6242 March

12, 2008 Mr. Donald

S. Welsh (3APOO)



# E C
F,

! ‘I


# E D Regional Administrator US Environmental Protection Agency Region

III 1650 Arch Street. Philadelphia,

PA, 19103-2029

I1W,iJI iiitt& (3t1) Dear Mr. Welch: On June

13, 2007,
the State

of Delaware submitted

two State Implementation

Plan (SIP) revisions entitled

(1) “Delaware

State Implementation

Plan for Attainment

of the 8-Hour Ozone National Ambient

Air Quality Standard, Reasonable Further Progress

and Attainment Demonstration,”

dated June 2007

on its cover page, and (2) “2002 Base Year State Implementation

Plan Emission Inventory

for VOC, NOx, and CO for the State

of Delaware,” dated June

1, 2007

on its cover page,

to EPA requesting

its approval

as revisions

to Delaware’s SIP pursuant

to section

110 of the Clean Air Act.’ The June
13, 2007 submittal consisted

of SIP revisions addressing

four elements required

by Sections 172(c)
and 182 of the Clean Air Act

as implemented

by Subpart

X of 40 CFR part

51 for moderate

and above 8-hour ozone nonattainment

areas. These elements

are (1) the 2002 base year emissions inventory,

(2) the

15 percent reasonable further progress
plan (RFP plan)
for 2008,

(3) the attainment demonstration, and (4) the contingency measures

for 2008 and 2009. The purpose

of this letter

is to identify

the RFP plan and related elements, including

the 2002 base year emissions inventory,

of the June 2007 SIP revisions

to make

it possible

for EPA to take action

to determine

the adequacy

of the mobile budgets

in the RFP plan. The 2002 base year inventory element

of the June

13, 2007 submittal, required under section

1 82(a)(

1) as implemented

by 40 CFR

§ 51.915, provides

a comprehensive, accurate, current inventory

of actual emissions
from

all source sectors, including source sectors

of stationary point sources, stationary non-point sources (formerly called area sources), on-roadl The first SIP document

is hereafter referred

to as “the June 2007 SIP plan”, arid the second
SIP document

is referred

to as “the 2002 base year inventory.” 

# Vela4ia4e

4 

# 9ood ltua’e deftecd4

otMr.DonaldS.WelchMarch12,2008Page#2mobilesources,non-road(oroff-road)mobilesources,andnaturalsourcesforVOC,NOxandCOemissions.AlthoughunderthesamesubmittalletterofJune13,2007,this2002baseyearemissioninventoryforthe8-hourozoneNAAQSwassubmittedtoEPAasseparateozoneSIPrevision(i.e.,notasaninclusivepartoftheJune2007RFPandAttainmentDemonstrationSIPplan).TheRFPplanelementoftheJune13,2007submittalprovidesforemissionreductionsby2008ofatleast15percentfrombaselineemissionsrequiredbySection182(b)(1)asimplementedby40CFR§51.910(a)(1)(i)(A).TheelementconsistsofthefollowingportionsoftheJune2007SIPplan:(1)Sections1and2oftheJune2007submittalserveforgeneralintroductorypurposes.Section1includesabriefdiscussionofthebackgroundfortheRFPelementandrelevantRFPrequirementsundertheCAAAandEPA’sguidancerules.Section2presentsananalysisofDelaware’sambientairqualityregardingtheprevious1-hourozonestandardandthecurrent8-hourozonestandard.ThesectionconcludesthatadecreasingtrendofambientozoneconcentrationsinDelawarehasbeenobservedinthepastdecadeorso,andthetrendislikelytocontinueinthefutureyears.(2)Section3providesasummaryofthe2002baseyearemissioninventory.SinceCOemissionreductionisnotrequiredintheRFPandattainmentdemonstration,thesummaryincludesthe2002VOCandNOxemissionsonly.TheVOCandNOxemissionsinthischapterareusedasbaseemissionlevelsforcalculatingRFPemissionreductionsinthechapterstofollow.(3)Section4providesdetailedcalculationsforassessing2008RFPemissionreductionsrequiredunderCAA.Specifically,Subsection4.1providesdetailsofhowDelawareadjuststhe2002baseyearVOCandNOxemissionlevels.InDelaware,theadjustmentsinvolveonlynon-creditablereductions,whicharesolelyduetotheimplementationofthepre-1990FederalMotorVehicleControlProgram(FMVCP)andReidVaporPressure(RVP)rule,andexistintheon-roadmobilesourcesectoronly.Asdiscussedinthissubsection,DelawareconductstheadjustmentsstrictlyfollowingEPA’sguidancedocumentsandthetimelyinstructionsprovidedbyEPA’sRegion3Office.Appendix4-1tothissectionprovidestheMOBILE6.2inputandoutputfiles,aswellasthedetailedcalculationsforobtainingthe2008’sadjustmentstothe2002baseyearmobileemissions.Subsection4.2providescalculationsforassessingthe15%VOCemissionreductionsby2008forSussexCounty(anmarginalnon-attainmentareawithoutanapproved15%VOCemissionreductionplanunderthe1-hourozonestandard),andforKent/NewCastleCounties(anseverenon-attainmentareawithanapproved15%VOCreductionplanundertheI-hourstandard).The2008VOCemissiontargetsforSussexCountyandforKent/NewCastleCountiesarealsocalculatedinthissubsection.Mr. Donald

S. Welch March

12, 2008 Page

#

3 (4) Section

5 provides calculations

for the 2008 emission projections

on existing

and upcoming control measures

in Delaware.

The calculations

are separate

for point source sector, non-point source sector, non-road

and on-road mobile source sectors

in subsections

5.1, 5.2, 5.3 and 5.4, respectively.

As explained

in Section

5,

a linear interpolating method

is used upon the 2002 adjusted
base year emissions

and the 2009 projections

for obtaining

the 2008 emission projections

for those source categories where there are no new controls between 2008 and 2009. Section

5 discusses

only the controls which

are new and/or specific

in 2008. Specifically, Subsection

5.1 discusses

the VOC emission control

on crude

oil lightering operation

in Sussex County,

the facility shutdowns

in Kent and New Castle Counties,

and the Consent Agreement

for NOx emission control

at Premcor Refinery

(a facility

in New Castle County); Subsection

5.4 discusses

the 2008 on-road mobile source VOC and NOx emission projections
using EPA’s MOBILE6.2
model with the 2008 VMTs based

on the most-recent-available vehicle registration

data and speed estimates. Appendix

6-3 (to Section

6 of this SIP plan) provides MOBILE6.2

input and output files,

as well

as the detailed calculations

for obtaining

the 2008 mobile emissions. Subsection

5.5 sunimarizes

VOC emission projections

in all

4 sources sectors

in Sussex County,

and
in Kent/New Castle Counties,

and concludes

that the existing

and upcoming controls

in Delaware

will lead

to VOC emission projections

that will meet the RFP emission targets

in both Sussex County
and
in Kent/New Castle Counties. (5) Section

9 provides

the 2008 on-road mobile source emission budgets

for transportation conformity.

As explained

at the beginning

of this section, Delaware

had developed

a mobile budget

SIP revision

and submitted

to EPA

in May 2007

to meet EPA’s requirements.
Section

9 briefly describes
how Delaware develops

the 2008 mobile budgets

and presents

the 2008 VOC and NOx budget numbers. Appendix

9-I
to this section provides

a complete
copy
of Delaware’s

May 2007 Mobile Budgets

SIP submittal. (6) Section

10 addresses

the contingency measures

in the 2008 milestone
year. Subsection 10.1 briefly discusses

the relevant requirements

under
the CAAA,

and guidance documents

from EPA. Subsection

10.2 provides details

of how Delaware managed

the contingency

issue
for 2008. This subsection concludes

that Delaware’s

NOx emission reductions

in 2008 will
be significantly beyond

the REF contingency requirements

(as indicated

in Subsection

5.4), and therefore

no contingency measures

are needed

to be specified

in 2008. Other sections and/or subsections

in the June 2007 SIP plan not discussed above
are related

to the attainment demonstration element

and the 2009 contingency measure element

of the June

13, 2007 ozone
SIP submittal.Mr.DonaldS.WelchMarch12,2008Page#4AlsoenclosedwithourJune13,2007,submittalswereadministrativeandothermaterialsrelatedtothepublicnoticeandhearingamongotherthings.ThesematerialsconstitutepartofthesubmittalforeachoftheSIPrevisionelementsdetailedabove.WelookforwardtocontinuingthecooperationbetweenDelawareandEPAintheattainmentoftheozoneNAAQS.PleasefeelfreetocontactAliMirzakhalili,AdministratorofDNREC’sAQMSection,(302)739-9402,ifyouhaveanyquestionregardingthisletterand/orourJune13,2007ozoneSIPsubmittal.SipcereIy,7.Ii;-.‘-.JohnA.1-lughesSecretarycc:JudyKatzAliMirzakhaliliJimWerner