UNITED

STATES ENVIRONMENTAL

PROTECTION

AGENCY REGION

7 MEMORANDUM

11201 Renner Boulevard Lenexa,

Kansas

66219 JUL

3

0 2014 SUBJECT:

Technical

Support Document

(TSD)

for

the Iowa

State Implementation

Plan

(SIP) Revision

for Fine Particulate

Matter

, Muscatine,

Iowa FROM:

Amy Algoe-Eakin

-

\ **~** Community

**Partner**

**~~**

**ms** Section

, Air Planning

and Development

Branch THRU:

Sara

Hert

z **Wu ~~~/J** 

, On detail

to Air **~dft>eve**

**lopment**

Branch Michael

Jay

, Section

Chief Atmospheric

Programs

Section, Air Planning

and Development

Branch Joshua

Tapp, Branch

Chief Air Planning

and Development

Branch TO:

IA-167; EPA-R07-0AR-2014-0550 I. INTRODUCTION Thi

s Technical

Support Document

(TSD) provides information

regarding

the Iowa

State Implementation Plan

(SIP) revision submitted

to address

the July

14, 2011,

U

. S

. Environmental

Protection

Agency (EPA) finding

that

the existing

Iowa

SIP

was substantially

inadequate

to maintain

the 2006 24-hour National

Air Quality Standard (NAAQS)

for fine particulate

matter

(PMz

. s)

in Muscatine

County,

Iowa (76

FR 41424

). As

a matter

of clarification,

EPA refers

to the Agency's

notice

of substantial inadequacy as

a "SIP Call,"

which directed

the state

to strengthen

their

SIP. In addition,

this TSD provides

the following information: 1

. provides regulatory background

for

this Agency

action

; 2. summarizes

the current ambient

air quality monitoring

data

for

the 2006

PMz

. s NAAQS

at the violating

monitor; 3. provides

EPA's evaluation

ofthe

state's submittal;

and 4. includes

the recommended

action

for Iowa's

SIP.

. Printed

on Recycled

PaperII.REGULATORYBACKGROUNDOnFebruary18,2014,thestateoflowasubmittedarequesttoamendtheIowaStateImplementationPlaninresponsetoEPA'sSIPCall.EPApromulgatedtheSIPCallbasedon2008-2010ambientairqualitydata,whichshowedthatamonitorwithinthecitylimitsofMuscatine,Iowawasinviolationofthe24-hourPM2.sNAAQS.AllportionsofMuscatineCountyaredesignatedasattainmentforthe24-hourPM2.sNAAQS,EPAbasedtheSIPCallonboththeviolatingmonitorandareviewofthemonitoringdata.Themonitoringdataillustratedthattheareatendedtooscillateaboveandbelowthestandard.ThemonitoringdataisdiscussedinmoredetailinSectionsIV.andV.B.ofthisTSD.ToissuetheSIPCallandaddresstheviolatingmonitor,EPArelieduponSection110(k)(5)oftheCleanAirAct(CAA).Section110(k)(5)provides,inrelevantpart,that"[w]henevertheAdministratorfindsthattheapplicableimplementationplanforanareaissubstantiallyinadequatetoattainormaintaintherelevantnationalambientairqualitystandard...theAdministratorshallrequirethatstatetorevisetheplanasnecessarytocorrectsuchinadequacies."Specifically,theSIPCallestablishedthefollowing:•theIowaSIPwassubstantiallyinadequatetomaintaintheNAAQSfor24-hourPM2.sinthearea;•requiredIowatoreviseandsubmittoEPAaSIPtomeetalloftheapplicablerequirementsofsection110oftheActwithrespecttoPM2.sinthearea,including'anemissionsinventory,modeledattainmentdemonstration,adoptedcontrolmeasurescindcontingencymeasuresasdescribedinEPA'sFebruary2,2011,proposal;•requiredtheStatetosubmitrevisionstotheSIPwithin18monthsoftheeffectivedateofthisrule;•requiredthatalladoptedmeasurestoachievereductionsdeterminednecessarytoattainandmaintainthe200624-hourPM2.sstandardbeimplementednolaterthanyearsaftertheissuanceoftherule;and•requiredthattheSIPprovideforattainmentandmaintenanceofthe200624-hourPM2.sNAAQSintheMuscatineCounty,Iowaareaasexpeditiouslyaspracticable.III.CHRONOLOGYOFSIPACTIVITIESACTIONDATEEPA'sFindingofFailuretoSubmitIssuedJuly14,2011EPA'sFindingofFailuretoSubmitEffectiveAugust15,2011May23,2013-firstpublicnoticeNovember15,2013-secondpublicMuscatinePM2.sSIPProposednoticeJune24,2013-firsthearingPublicHearingDecember18,2013-secondhearingSIPApprovedbyIowa'sEnvironmentalProtectionCommissionFebruary18,2014RulepackagereceivedbyEPA,R 7February24,20142In2011,whentheSIPCallwasfinalized,themonitoringdataindicatedthearea,althoughdesignatedasattainment,violatedthe200624-hourPM2.sstandard.The2006standardfor24-hourPM2.swassetatalevelof35micrograms(J.lg)ofparticulatematterlessthan2.5micrometers(J.lm)indiameter,percubicmeterofair(m3).Thestandardismetwhenthe3-yearaverageofthe98thpercentileof24-hourconcentrationsisequaltoorlessthan35J.lg/m3.Thecomputationofthis3-yearaverageofthe98thpercentilesof24-hourconcentrationsiscommonlyreferredtoasthedesignvalueandisbasedonthemostrecentthreeyearsofqualityassureddata.CleanAirActsection110(a)(2)(B)requireseachstatetoestablishandoperateappropriatedevices,methods,systemsandproceduresnecessarytomonitor,compile,andanalyzedataonambientairquality.Pursuanttothisauthority,thestatemaintainsanetworkofairqualitymonitorsforPM2.sinaccordancewith40CFRPart58whichmeetsapplicablerequirements.MonitorscalledStateorLocalAirMonitoringStations(SLAMS)makeuptheambientairqualitymonitoringsiteswhosedataareprimarilyusedfordeterminingcompliancewiththeNAAQS.InMuscatine,thereare3SLAMSmonitors.OnemonitorislocatedattheGarfieldElementarySchoolandisreferredtoasthe"GarfieldSchoolmonitor."Historically,theGarfieldSchoolmonitorhasrecordedfluctuatingPM2.svaluesverynearorabovetheNAAQS.EPAbaseditsSIPCallontherecordedviolationsofthe24-hourPM2.sNAAQSattheGarfieldSchoolmonitor.Table1includespastandmostrecentdesignvaluesattheGarfieldSchoolmonitor,includingthecertifiedSLAMSdataforcalendaryear2013,submittedbyIowaonApril30,2014,inaccordancewith40CFRPart58.Asnotedonthistable,sinceEPA'sJuly2011finding,therehasbeenadecreaseinmonitoredconcentrationofPM2.s.Figure1visuallydisplayselevenyearsof24-hourPM2.smonitoringdata.AsindicatedinFigure1,theambientairqualitymonitorsvaluesaredeclining.AlthoughTable1andFigure1captureonlydatafromtheGarfieldSchoolmonitor,thetwoadditionalmonitorsinMuscatineremainincompliancewiththe24-hourPM2.sNAAQS.Table1.DesignValuesattheGarfieldSchoolMonitorMonitoringYearsDesignValue(J.lg/m3)2001-2003352002-2004352003-2005382004-2006342005-2007362006-2008352007-2009382008-2010372009-2011352010-2012322011-2013283Figure1:PM2.sDesignValueTrendsatGarfieldSchoolPM25DesignValuesatGarfieldSchool40I•35••ME3025-Q):::::120i'ii>15ct:10·v;10Q)0502001-2002-2003-2004-2005-2006-2007-2008-2009-2010-2011·20032004200520062007200820092010201120122013-+-Series13535 38.3436 3538373532YearsV.ANALYSISOFCLEANAIRACTREQUIREMENTSConsistentwithSection110oftheCleanAirActandtherequirementsincludedintheSIPCall,theStatesubmittedtherequiredplanelementstocorrecttheinadequacyoftheSIP.Thesespecificelementsare:(1)arevisedemissioninventoryforallsourcesthatcouldbeexpectedtocontributetotheviolatingmonitorbecauseoftheirsize,proximity,orotherrelevantfactorsconsistentwith40C.F.R.§51.114(a);(2)amodelingdemonstrationtoachievereductionsdeterminednecessarytoattainandmaintaintheNAAQS,withenforceableschedulesforattainingtheNAAQSasexpeditiouslyaspracticable;(3)adoptedmeasurestoachievereductionsdeterminednecessarytoattainandmaintaintheNAAQS,withenforceable schedulesforimplementingthemeasuresasexpeditiouslyaspracticable;(4)contingencymeasuresthatwillbetriggeredifthemonitoringvalueisabovethelevelofthestandardinthecalendaryearfollowingtheimplementationofcontrolsnecessaryforattainment.Iftriggered,thecontingencymeasureswouldneedtobeimplementedinanexpeditiousandtimelymanner.A.EmissionsInventory428IntheSIPCall,EPAstatedthatthestatemustincludeintherevisedSIPanemissionsinventoryconsistentwith40CFR§51.114.40CFR§51.114providesforidentificationofemissionsdataandprojectionsandstatesthateachplanmustcontainadetailedinventoryofemissionsfrompointandareasources.IowahasadequatelyaddressedthisrequirementinitsSIPrevision.Iowareviewedtheaverage2007and2008facility-wideactualemissionsfromthefacilitiesshowntocontributesignificantlytoviolationsofthe24-hourPM2.sNAAQS.Buildinguponthetechnicalanalysiswhichoccurredduringthedesignationsprocessforthe200624-hourPM2.sNAAQSandinreviewinginventoryforthedevelopmentofmodeling,thestatedeterminedthreesourcessignificantlycontributedtotheGarfieldSchoolmonitoredviolations:GrainProcessingCorporation(GPC),MuscatinePower&Water(MPW),andUnionTank Car(UTC).Becauseoftheformofthestandard(24-houraverage),localsourcesweredeterminedcriticalintermsofcontributionstoambientPM2.sconcentrations.Thestatedidnotidentifyanyotherpotentialemissionssourcesintheareaoftheviolatingmonitor,suchasareaandmobilesources,ascontributingsignificantlytotheNAAQSviolations.Backgroundconcentrationswereaddedtomodeledresultstoaccountfortheregionaltransportoffineparticulatematterandanyunidentifiedlocalsources,suchasmobileandareasources,notexplicitlyincludedinthemodel.Table2isalistingofthethreefacilitiesandtheirPM2.semissions.TheactualemissionsrepresentdirectPM2.semissionsthatwerereportedbythefacilitiestotheDNRontheannualemissionsinventoryquestionnaires.PM2.sactualemissionsvaluesformanyofGPC'semissionpointswerefurtherrefinedusinghourlyemissionratesderivedfromacombinationofPM10andPM2.sstacktestingdataandinformationregardingthefractionofPM2.sinemissionssampledbyGPC.Table2:Facility-WideActualPM2.sEmissionsActualPM2.sEmissionsFacilityNameFacilityID_(tonsll'_ealj_GrainProcessingCorporation70-01-004537.6MuscatinePower&Water70-01-01158.3UnionTankCarCompany70-01-0483.0Total598.9B.ModeledAttainmentDemonstrationIntheSIPCall,EPArequiredthestatetosubmitamodeledattainmentdemonstrationwhichisconsistentwith40CFRpart51,AppendixW.40CFRpart51.ThemodelingwasrequiredtodemonstratewhatreductionswillbeneededtoattainandmaintainthePM2.sNAAQSinthearea.ThestateadequatelyaddressedthisrequirementinitsSIPrevision.TheSIPRevisionincludesadetailedexplanationofthemodelingconducted.Includedinthestate'splanisadiscussionofmodelselectionandoptionsincluding:theextentofthereceptorgrid,receptorgridspacing,terrainelevations,downwash,andmeteorologicaldata.Thestatealsoprovidesbackgroundastotheiterativeanalysesconductedaswellasthedetailed developmentofmodelinputsforemissionsandmeteorology.5

# During

the development

of the plan

and

in previous

technical

modeling conducted

during

the initial designations

of the 24-hour

PM2.s NAAQS,

EPA provided

technical

expertise

to the state regarding

these modeling

activities.

EPA Region

7 reviewed

and provided

comment

on the state's modeling

protocol

during

the development

of the

SIP revision.

(The modeling

protocol

is included

in the state's

SIP

as Attachment

A.) 

# In evaluating

the

SIP revision

for consistency

with Appendix

W

to

40 CFR

part

51, EPA Region 7 believes

the state

SIP revision

to be consistent

with EPA's modeling requirements.

Because local

point sources

are considered

to be

the significant contributors

to the monitor's

24-hour PM2.s violations,

the state's modeling

was conducted

using AERMOD

version

12345.

Again,

the model selection,

modeling

inputs

such

as background concentrations

and significant

impact levels,

and results

of modeled attainment

tests

were subject

to consultation

with

EPA Region

7 before completion

of the control strategy selection. 

# C. Adopted

Control Measures In order

to meet

the requirements

of the

SIP Call,

Iowa developed

a control strategy

for Muscatine

County

that includes

the three sources

that Iowa determined

contributed

to the monitored

violations

at the Garfield

School monitor. 

# 1. GPC Grain Processing Corporation

or GPC

is located approximately

500 meters east/southeast

of the Garfield

School monitor.

GPC processes

grain

into industrial,

beverage,

and fuel-grade

ethanol, grain based

food products,

industrial

products,

and animal

feeds.

GPC

has nearly

200

PM2

. s emission

points, including

coal

and gas-fired

boilers,

dryers,

coolers

and associated

material handling

and storage equipment.

GPC's

facility

is 70 years

old.

It



# is located

on

135 acres immediately

adjacent

to the Mississippi

River.

The facility

has grown

over

time through

the expansion

of various processes

in accordance

with demand

and product development

and

by acquiring

land adjacent

to

its original location.

The facility footprint

is very limited

and

is bounded

by residential

property

on

the north

and west,

and

a municipal

utility property

on the south

. Because

of the location,

the existing

plant

has minimal

unused

space

for plant modifications

and additional equipment. Iowa's

control strategy

for GPC

is memorialized

in Administrative

Consent

Order

No

.2014-AQAl

(" ACO")

and

is included

as part oflowa

' s SIP revision,

as SIP Attachment

B

1

• 

# The ACO includes

a schedule

for implementing

the control strategy

as well

as recordkeeping,

reporting, and testing requirements.

The provisions

of the ACO

will

be incorporated

into permits,

which will

then

be submitted

to EPA

for approval

into

the state

SIP.

The control strategy

includes numerous

and substantial

changes

at the facility.

The control measures

include:

new particulate controls

or improvements

to existing particulate

controls

on

a number

of sources; shutdown

of existing equipment; replacement

of old equipment;

installation

of more efficient equipment; 1 

# As stated

in 

# Iowa's

SIP submission

letter

of February

18

, 2014,

Iowa

did

not submit

Section

III, Paragraph

5, the last sentence,

or Section

VI

to EPA

for approval. therefore,

those provisions

of the 2014

ACO

are

not part oflowa

' s SIP

and

are

not considered

by EPA.



# 6regularsweepingandwateringofroadsurfaces;increaseofstackheights;andoperatingrestrictionsoncertainprocesses.AsdescribedindetailinAttachmentAtotheACO,GPChasalreadyimplementedthecontrolstrategyatmanyofitsemissionpoints.Thisincludesoperationalrestrictions,PM2.semissionlimits,shutdownofemissionunits,andstackheightincreases.AlthoughGPChasalreadycompletedseveralcontrolstrategyactivities,thereareseverallarge-scaleprojectsthatrequiresubstantialplanningandconstructionbyGPC.DuetothescaleandcomplexityofthecontrolmeasureimplementationatGPC,GPChasdevelopedaphasedimplementationschedulethatisalreadyunderwayandconcludesinDecember2016.ManyofthechangesatGPCarecontingentuponcompletionofasignificantprojectrelatedtoanewdryerhouse(DryerHouse#5orDH5)thatwasrequiredunderthe2006ConsentOrderenteredintobetweenGPCandtheStateofIowatoaddressPMtoemissions.ThisprojectisalsoincludedinIowa'sSIPrevisiontoaddressthe2006PM2.sNAAQS.TheDH5projectisa$75millionfeeddryerinstallation.ThedryerisaSwissCombidryer,whichisastate-of-the-artfeeddryingsystemthatispartiallydesignedandmanufacturedoverseas.Allthebuildingsthataretobeconstructedforthisprojectareenclosedunderasinglestructure.DH5andtheassociatedequipmentwillbelocatedonthefloodplainoftheMississippiRiver,whichiscomprisedofloose,sandysoil.Therefore,specialstructuralfootingsmustbedesignedandinstalled.InordertoconnectDH5totheexistingplant,GPCmusttie-inDH5inastagedfashionthatrequirescoordinated,plannedprocessshutdowns.TheSIPCalloccurredatthesametimeGPCwasinprocessofdesigningtheDH5projecttocomplywiththe2006ConsentOrder.TodemonstratecompliancewiththePM2.sSIPCall,GPCre-evaluatedtheDH5projectandmadeadjustmentstothedesigntoaccommodatethemorestringentplant-widechangesrequiredbythePM2.sSIPCall.AsaresultofthechangestotheprojecttocomplywiththePM2.sSIPCall,thedesigncomplexityandconstructionlogisticsfortheDH5project,GPCwillcompletetheprojectonMarch31,2015.ThecontrolstrategyincludesseverallargescaleprojectsthataretiedtotheinstallationandcompletionoftheDH5project.Theyaredescribedbelow.GPCwillroutetheDryerHouse4(DH4)millingsystemsthroughanewbaghouseandremovesixemissionpoints.ThisprojectrequiresmodificationstomultiplestoriesoftheexistingDH4processbuilding;multiplenewpneumatictransportationandcoolingsystemsforproductthatleavestheexistingdryers5,6,and7;aproductpneumaticreceivingbaghouse2; ahighstaticinduceddraftfan,anairlock,spoutingandamill.ThecompletionofthisprojectistiedtotheDH5projectaswellasseveralotherprojectsinthecontrolstrategy.TheDH5projectwillreplaceelevenexisting,operatingdryers.ThespacerequiredforthenewDH4millingsystemisoccupiedbyequipmentthatiscurrentlyoperating,butwillbereplacedbytheDH5project.Therefore,theDH4millingsystemprojectrequirescoordinatedprocessshutdownsforthecompletionoftie-insthroughthisareaoftheplant.DH5mustbeon-linetoallowforshutdownandtie-inofothersources.Duetothecarefulcoordinationneededtosystematicallyshutdownandtie-intheDH4millingsystem,GPCwillcompletetheproject12monthsafterthestartupofDH5,byMarch31,2016.2Productentersthebaghouseonapneumaticconveyorbelt.7GPCplanstodecommissionDryerHouse3(DH3),whichincludesremovaloffouremissionpoints.ThisprojectisdirectlytiedtothecompletionandstartupoftheDH5project.DH5willreplacethedryingcapacityofDH3.FornormalplantoperationtooccurduringtheDH5project,DH3mustbeinoperationuntilDH5canaccommodatetheload.DH3willbeshutdownwithin30daysofthestartupandoperationofDH5,whichwillbebyApril30,2015.GPCwilldecommissiontheGlutenPlant1#3Dryerandtheassociatedemissionpoint.ThisprojectisdirectlytiedtothecompletionandstartupoftheDH5project.DH5willreplacethedryingcapacityoftheGlutenPlant1#3Dryer.FornormalplantoperationtooccurduringtheDH5project,the#3DryermustbeinoperationuntilDH5canaccommodatetheload.The#3Dryerwillbeshutdownwithin30daysofthestartupandoperationofDH5,whichwillbebyApril30,2015.AsaresultoftheDH5project,GPCwilladdandremovecertainemissionpointstiedtotheproject.ThenewemissionpointsareassociatedwithDH5andwillcomeonlinebyMarch31,2015.Theremainingsourcesthatwillbedecommissionedareassociatedwithdryingsystems,includingfeeddryers,producthandlingand/ormillingsystemsthatwillbereplacedbyDH5.AsDH5comesonlinethesourceswillbetakenoffline.TheycannotbetakenofflineuntilDH5isfullyoperationalbecausedryingoffeedisessentialtokeeptheplantinoperation.GPCwilladdandremovethesourcesbyMarch31,2015.GPCwillmodifytheSprayDryer#3MaltrinScrubbersandextendallMaltrinstacks.Thisprojecthasacomplexscopeofwork.Spraydryer#3atMaltrinhastwostacks,eachwithaventuriscrubber.Bothscrubberswillbemodifiedduringthisproject.GPCwilladdpackedbedsectionsthatmustbedesignedspecificallyforthosescrubbers.GPCplanstocompletenineseparatestackextensionsontheMaltrinbuildingroof.Thestructuralcagesandtrussesfortheseextensionsmustbedesigned,fabricated,andinstalled.Inordertominimizedisruptiontoproduction,GPCmustplanandcoordinatethismodificationwiththeotherprojectsthatareoccurringatthefacility.Thisprojectalsorequirestie-instoseveralotherprojects,includingDH5.GPCwillcompletethisprojectbySeptember1,2016.GPCwillinstallscrubbersonDH4rotarydryers5,6,and7,andrelocatethestack.Thisisanotherprojectthathasanextensiveandcomplexscopeofwork.GPCwillinstallthreeseparatescrubbersystems,includingscrubbers,fans,circulationpumps,heatexchangers,andfilters.Toaccommodateascrubberandastackextension,theexistingstackswillbeabandonedandnewstackswillbeinstalledatadifferentlocation.GPCmustmakestructuralmodificationstothesouthsideoftheDH4buildingtoaccommodatethescrubberequipmentandnewstacks.GPCisalsoundertakingfeedmillingmodificationsatDH4asdescribedabove.BecausethisprojectistiedtoboththefeedmillingmodificationsandtheDH5project,GPCwillcompletethisprojectbyNovember1,2016.GPCmustdelaythestartofthescrubberinstallationuntilDH5isfullyoperationalbecauseDH5mustaccommodatetheadditionaldryerfeedloadthatwillbelostduringtheinstallationofthescrubbersontherotarydryers.Thecontrolstrategyalsoincludesseverallargescaleprojectsthatarecomplexinallaspects,includingdesignandconstructionandwillrequireanextendedscheduletocomplete.8ThecontrolstrategyrequiresGPCtolimitemissionsonthesixcoal-firedboilersatthefacility.3Thesecoal-firedboilersareassociatedwiththeemissionpointnamedtheGEPstack.ThecontrolstrategyrequiresGPCtomeettherequirementsofthe40CFRPart63,SubpartDDDDD(BoilerMACT),nolaterthanJanuary31,2016.ThecontrolstrategyallowsGPCtochoosethemethodofcompliancetomeettherequirementsoftheBoilerMACT,butalsorequiresGPCtomeetaPMz.semissionlimitof36.400pounds/hourbyJanuary31,2016.AspartoftheSIPCallcontrolstrategyGPCwillimprovethedryerandscrubber performanceofGlutenPlantUnits1and2.Theseimprovementsalsoinvolveanincreaseinthestackheightto140feet.TheadditionofanadditionalglutenrotaryvacuumfilteratGlutenPlant2willimproveallaspectsofglutendryingattheplantandwillallowGPCtoeffectivelyreduceaveragedewateringanddryingfromGlutenPlant1toallowGPCtoshifttheprocesstotheGlutenPlant2dryer.ThiswillallowGPCtoruntheGlutenPlantUnit1dryersataconsistentlylowerrate,whichwillreducefineparticulateemissionsfromtheGlutenPlantUnit1dryersandtheexistingscrubberandmaketheglutendryingprocessmoreefficient.GPCwillsubmitapermitapplicationfortheadditionalglutenrotarydryingvacuumfilteratGlutenPlant2.ThefinaldesignandconstructionplanningcannotbeginuntilafterthepermithasbeenobtainedfromIowa.Theexistingscrubberstackextensionwillrequiredesign,fabrication,andconstructionofastructuraltruss,tiedbacktotheexistingsteel,forstructuralsupport.ProcessshutdownsatGlutenPlant#1andotherprocessesatthefacilitywillhavetobecoordinatedtoallowforthetieintothescrubber.TheadditionalglutenrotarydryingvacuumfiltertobeinstalledatGlutenPlantUnit2willallowGPCtomaintain productionwhilethedryingloadfromGlutenPlant1isshiftedtotheGlutenPlant2dryer.GPCwillupgradethepackingandflowthroughtheexistingscrubberduringthescheduledshutdownofGlutenPlant1.Multipleshutdownswillberequiredtoallowfortie-instocompletethisproject.GPCexpectstocompletethisprojectbyAugust1,2016.GPCwilldecommissionalltheP&Sdryersandconvertflashdryers1and2tonaturalgas.GPCmustobtainpermitstoconvertflashdryers1and2tonaturalgas.GPCexpectsthatthepermittingprocesswilltake9-12monthstocomplete.GPChasalreadybegunworkingontheburnerandstackdesignforthisproject.Theconversionwillrequireacompletere-designofbothflashdryersincludinglargeinletductworksystems,designofburnerandburnermanagementsections;contractorreviewofburnerdesignandfuelsafetyprovision,removalofexistingsteamcoils,steamandcondensatehandling,piping,andequipment.Thisprojectrequiresnewductworkwhichwillbedesigned,built,andinstalledtoaccommodatethenewburnersectionsandallowspaceforheatrecoverycoilstobeinstalled.Thisprojectrequirescivil/structuraldesign,burner·ductdesign,bidpackagegeneration,mechanicalandelectricalcontracts,andprocurementofmaterials.Aswiththeotherprojects,eachpiecewillneedtobeshutdowninacoordinatedfashioninordertomeetcustomerdemand.Duetothecomplexitywithdesign,engineering,andconstructionofthisproject,GPCwillcompletethisprojectbyDecember31,2016.3Boiler#5isshutdown.9GPCisalsoincreasingthestackheightofthestacksonflashdryers1and2.ThisprojectissimilartotheGlutenPlant#1stackheightincrease.GPChasalreadystartedthedesignevaluationforthisproject.Theprojectwillincludecivilstructuralengineeringreviewoftheconnectionpointsanddesignofthestructuralcages/trussesthatwillsupporttheweightandlateralwindloadingfrom40footstackextensions.Thestacksforthisprojectswillbe96"indiameter,therefore,thestackswillrequiresubstantialstructuralloadstowithstandwind.Inaddition,anyflowchangesfrominstallingnaturalgasfiringonflashdryersandattheboilersmustbeconsideredinthenewstackdesign.Inordertogainthemaximumefficiency,thestackheightincreasesshouldbetiedtothenaturalgasfuelconversions.ThestackheightincreasewillbecompletebyDecember31,2016.Aspartofthecontrolstrategy,GPCwill restrictpublicaccesstotheleveelocatedbetweenGPC'spropertyandtheMississippiRiver.GPCwillpostsignsofwarningonthenorthandsouthfencelinesthatintersectthelevee.Thesignswillalsostatethatloiteringandfishingontheleveeintherestrictedaccessareasisprohibited.GPCsecuritystaffwillconductsurveillanceoftheleveethroughoutthedayandwilldocumentsurveillancetimesandlocations.TheleveerequirementsareincludedinAttachmentAtoGPC'sACOandwillbeincludedinapermittoensureongoingimplementationoftherestrictedaccess.InadditiontothesignificantmodificationsGPCisundertakingaspartofthecontrolstrategy,GPCisalsovoluntarilyimplementingacomtruckqueuingandidlingpolicy.ThepolicyisnotsubmittedaspartofthecontrolstrategyfortheSIPrevision,butwillreducePM2.s,NOxandS02,emissionsandalleviatetrucktrafficcongestionnearthefacility.ThepolicyisdesignedtoreduceoverallcomtruckwaittimewhichwillresultinlowerPM2.semissionsfromtruckidling.Reductionsinidlingtimewillbeachievedthroughschedulingandprocessingpracticesasdescribedinthepolicy.ThecontrolstrategyforGPCismadeenforceablethroughAdministrativeConsentOrderNo.2014-AQ-A1,submittedaspartoflowa'sSIPrevision.ThisACOwillbecomepartoftheSIPonceEPAhasgrantedfinalapproval.ThisdocumentwillremaininplaceuntilIowaissuespermitsforallthesourcesandemissionspointsintheSIP.Oncethepermitsareissued,thosedocumentswillbeincorporatedintotheSIPinafutureSIPactionandwillalsobefederallyenforceable.FullimplementationofthecontrolmeasuresatGPCwillreducePM2.semissionsfromGPCbyanestimated367.9tons/year.SeeTable3forasummaryoftheemissionreductionsexpectedfromtheimplementationofthecontrolstrategy.Thecomplexityofthedesign,fabrication,andconstructionoftheprojectsatGPCsupportsthephasedimplementationschedule,andalthoughthefullimplementationoftheGPCcontrolstrategyisnotscheduledtobecompleteuntilDecember31,2016,EPAunderstandsthatGPChasbegunandcontinuestoimplementthecontrolstrategy.Further,approvalofthephasedimplementationscheduledoesnothaveanegativeeffectonairquality.AsdiscussedintheairqualitymonitoringportionoftheTSD,the24-hourPM2.sdesignvalueshavebeensteadilydecliningoverthelastthreedesignvalueperiods.Theon-goingimplementationofcontrolspursuanttothecontrolstrategywillensure thatfuturedesignvaluesstaybelowthe24-hour10PM2.sNAAQSandwilleliminatetheoscillationofthedesignvaluesaroundthePM2.sNAAQS.Baseduponthemultitudeoffactorsdiscussedabove,includingthecomplexityofthecontrolmeasuresandthedependenceofeachcontrolprojectonanother,EPAbelievesthattheGPCcontrolstrategyrepresentsattainmentasexpeditiouslyaspracticable.2.UnionTankCarUnionTankCar(UTC)suppliesandreconditionsrailtankcarsforusethroughrentalagreements.ThepqmarysourcesofPM2.sfromUTCarefromtheremovalofpaintfromrailtankcars,repairofrailtankcars,andapplicationofpaintthroughaspray systemonrailtankcars.UTCisnotamajorsourceofPM2.s,butislocatedneartheGarfieldSchoolmonitor.IowadeterminedthatUTCcontributedtopredictedviolationsofthePM2.sNAAQS.Therefore,IowaincludedUTCinthecontrolstrategy.Aspartofthecontrolstrategy,UTCisinstallingnewparticulatecontrolsonseveralemissionpoints.Itisalsoincreasing stackheightsatselectlocationsandrestrictingoperationsofcertainprocesses.FullimplementationofcontrolmeasuresatUTCwillreducePM2.semissionsfromUTCbyanestimated0.3tonsperyear.TheUTCcontrolmeasuresaremadeenforceablethroughstate-issuedairconstructionpermits,whichwillbepartoftheSIPonceEPAhasgrantedfinalapproval.AllofthecontrolmeasuresatUTChavebeenimplemented.3.MPWMuscatinePower&Water(MPW)isamunicipalelectricgeneratingstationlocatedapproximately1.6kilometerssouthandeastoftheGarfieldSchoolmonitor.TheprimarysourcesofPM2.satMPWincludeemissionsfromthreecoal-firedboilers,Units7,8,and9,andemissionsfromtheassociatedhandlingandstorageequipment.Aspartofthecontrolstrategy,MPWwillconductregularwateringofroadsurfaces;paveanunpavedroadandwaterroadsurfaces;removealimesiloandmixingtank,3dieselengines,andwetflyashtruckloading;andimplementoperationalrestrictions.MPWwillalsoreducethecapacityofitslimestonehopperloadingandhandlingsystems;installaroofedenclosurewiththreesidesforthelimestonehopper;andreducethesizeofthecoalpile,limestonepileandsyntheticgypsumpile.MPWismodifyingitsdustcollectionsystemforitscoalreclaimandthecoalcrushfeedersbyreconfiguringtheequipmentandincreasingthestackheight.TheMPWcontrolmeasuresaremadeenforceablethroughstate-issuedairconstructionpermits,whichwillbepartoftheSIPonceEPAhasgrantedfinalapproval.AllofthecontrolmeasuresatMPWhavebeenimplemented.ThefullimplementationofthecontrolstrategyatMPWisexpectedtoreducePM2.semissionfromMPWbyanestimated0.7tonsperyear.4.ConclusionEPAisproposingtoapprovethecontrolstrategyandestablishtheattainmentdatepursuanttotheSIPcalltoDecember31,2017,becausethisdateisasexpeditiouslyaspracticablefortheareatoreachattainment.EPAisproposingthiscompliancedatebasedupontheinformationinIowa'sSIP,ourreviewofthesupplementalinformationprovidedbyGPCbyemaildatedApril1129,20144asdescribedindetailabove,andthecurrentairqualitymonitoringdatafortheMuscatinearea.IntheSIPCall(76FR41424)EPAstatedthatwewouldestablishaspecificdateforattainmentatthesametimewetookfinalactionontheState'simplementationplanrevisioninresponsetothisfinalSIPCall.76FRat41426.InthisproposedactionweareestablishingDecember31,2017astheattainmentdate.Thecontrolstrategyincludespermanentandenforceablecontrolsthatdemonstratecontinuedattainmentofthe2006PM2.sNAAQS.Table3.IDNRSummaryofEstimatedPMz.sEmissionsReductionsfromImplementationofControlStrategyActualEmissionsReductionsEstimatedPercentFacility(tons/year)*(tons/year)ReductionGPC537.6367.968.4%MPW58.30.71.2%UTLX3.00.310.0%Total598.9368.961.6%*Basedonaverageof2007and2008productiondataD.ContingencyMeasuresIntheSIPCall,EPAstatedthatitwasreasonabletoexpectthatthe98thpercentilevalueof24-hourconcentrationsforthecalendaryearafterthenecessarycontrolswereimplementedshouldbeatorbelowthe24-hourPM2.sstandard(35ug/m3).76FRat41426.EPAstatedthatcontingencymeasureswillbetriggeredifthatvalueis·abovethe98thpercentilevalueinthecalendaryearaftertheimplementationofcontrolsnecessaryforattainmentorinanysubsequentyear.Id.EPAthenstatedthattheSIPrevisionmustcontainanenforceablecommitmenttoadoptandimplementsufficientcontingencymeasures,oncetriggered,inanexpeditiousandtimelyfashionthatiscomparableandanalogoustotherequirementsforcontingencymeasuresinCAAsection175A(d).Id.EPAdeterminedthatthereferencetoCAAsection175A(d)waswarrantedbecauseEPAmadetheSIPcalltoensurethattheareaattainsandthencontinuestomaintainthePM2.sstandard.76FRat41428.AtthetimeoftheSIPCall,Iowadidnotcommentontheproposedcontingencymeasuretrigger.Id.InIowa'sSIPrevision,Iowaincludesaphasedapproachtothecontingencymeasuresandtriggers.Iowastateditwilluseaviolationofthe2015-2017(oranysubsequent)PM2.sdesignvaluemeasuredfromtheGarfieldSchoolmonitortodeterminewhethercontingencymeasuresshouldbeimplemented(firsttiertrigger).Thecontingencymeasureswouldthenbeimplementednolaterthan24monthsasstatedintheSIPCall.Ifacontingencymeasureistriggered,Iowawouldthenusethe98thpercentilevalueforanysubsequentcalendaryearfollowingtheimplementationofcontingencymeasurestodeterminetheneedforadditionalmeasures(secondtiertrigger).4Thisinformationisincludedinthedocketforthisaction.12If the

98th percentile

for any subsequent

calendar

year following

the implementation

of contingency

measure

is above

35 J1.g/m

3 then additional contingency

measures

would

be implemented

as expeditiously

as practicable,

but

no later

than

24 months

after

the second

tier

of contingency

measures

is triggered.

Like

the contingency

measures implemented

as

a result

of the design

value trigger

(first

tier trigger),

the additional contingency

measures implemented

as

a result

of the

98th percentile

trigger (second

tier trigger)

would continue indefinitely

and become part

of the permanent

**~ontrol** strategy

for

the area. Iowa stated

in

its submission

that

it proposed

this

two

tier approach

because

Iowa believed

the SIP

Call trigger

(98th percentile

in the calendar

year following implementation

of controls)

did not adequately

consider

the potential

role

of regional (non-local)

events.

Iowa reviewed

the statewide

historical

98th percentile

PM2.s monitoring

data

for

the past

10 years. Iowa's

review showed

that

if the

SIP

Call trigger

was used,

many communities

in eastern

Iowa

that

are

not adjacent

to direct sources ofPM2.s

and

that

are

not currently designated

as non-attainment

for

the 24-hour

PM2

. s NAAQS,

would

have

been designated non-attainment

for

the 24-hour

PM2.s NAAQS

due

to regional

PM2.s episodes.

Iowa

also found

that

the

SIP

Call trigger

failed

to account

for

the documented

year-to-year

variability

of meteorological

conditions.

The annual variability

of meteorological

conditions

is accounted

for

in the form

of the 24-hour

PM2.s standard,

which

uses

a three-year

average

of 98th percentile

values. EPA commented

on this approach

during

the public comment

period

on Iowa's proposed

SIP revision.

Iowa stated

that

the

two

tier trigger approach

allows

for

the triggering

of contingency measures

on

the same

time schedule

that would

have

been applicable

with

a trigger

based

only on

the

98th percentile

value

for

the calendar

year

after complete implementation

of the control strategy. Section

175A(d) contingency

measures

are required

as part

of SIPs

to assure

that

a state

will promptly

correct

any violation

of the standard

which

occurs

after

the redesignation

of the area

as an attainment

area.

The contingency

measures

shall include

a requirement

that

the state

will implement

all measures

with respect

to the control

for

the

air pollutant concerned

which

were contained

in the

SIP

for

the area before redesignation

of the area

to attainment.

In the

SIP Call, EPA stated

that

it did

not intend

to imply

that section

175A(

d)

is literally applicable

to the Muscatine

area,

but rather provided

that IDNR

follow 175A(d)_as

a guide

for developing

and implementing

contingency

measures.

76 FRat 41428.

At

the time

of the

SIP Call,

EPA believed

it was reasonable

to expect

the

98th percentile

would

be

the appropriate

trigger

for implementing

contingency

measures.

76 FRat 41426.

After reviewing

Iowa's

SIP revision

and the associated contingency

measures,

EPA believes

that

the

SIP revision

meets

the requirements ofthe

SIP Call.

Iowa

has used Section

175A(d)

as guidance

in developing

the contingency measures,

as required

by

the

SIP Call.

The contingency

measure

trigger proposed

by Iowa

is also reasonable.

The

first contingency

measure

trigger

using

the design

value

to determine whether

there

is

. a violation

is consistent

with

the 2006

PM2.s NAAQS.

The second contingency measure

trigger

using

the

98th percentile

value

is consistent

with EPA's

SIP Call.

Iowa

will immediately

implement

the contingency

measures

as described

below,

upon reaching

the first trigger.

EPA

has carefully

reviewed

the control strategy

and

the contingency

measures proposed

and agrees

that

the design

value trigger

for

the contingency

measures

is reasonable, 13giventhestrengthofthecontrolstrategyandthecontingencymeasuresproposedandthecurrentdesignvaluedataof28ug/m3•EPAisproposingtoadoptIowa'stwotiercontingencymeasureapproach.Thetwotierapproachisprotectiveofairqualityandprovidesforacomprehensiveapproachtocontingencymeasures.Therefore,EPAproposestoapproveIowa'stwotiertriggerforthecontingencymeasures.Intheeventthatthe2015-201724-hourPM2.sdesignvalueexceedsthe24-hourPM2.sNAAQSattheGarfieldSchoolmonitor,Iowawillrequirethesubmissionofanemissionscontrolprogramfromtheappropriatesourcesinthearea.Iowawilldeterminewhichsourcesarerequiredtosubmitanemissionscontrolprogrambasedonthecircumstancesthattriggeredtheexceedance.Iowadevelopedexamplesofpotentialcontingencymeasuresthatmayprovideadditionalreductionsintheeventofanexceedance.Theseincludethefollowing:•evaluateandinstalladditionalcontrolequipment,asneeded;•eval.uateandimplementchangesinstackparametersandstackconfigurationstoimprovedispersionofemissions;•evaluateandimplementadditionaloperationandproductionrestrictions;•evaluateandimplementprocesschangestoreducePM2.sandPM2.sformation;•reviewoperationsandmaintenanceprocedurestodeterminewhetherimprovementscanbemade;•re-evaluatetrafficflowpatternsatfacilitiesandvehiclemilestraveledtodeterminewhetheridlingtimeandcongestioncanbereduced;•re-evaluatematerialproduceunloading,handling,andloadingproceduresandpatterstodeterminewhetherimprovementscanbemade;•re-evaluatefacilitybestmanagementpracticesassociatedwithhousekeepingincludingcleaninginternalandexternalareastominimizedustwhenthefacilityisreceiving,transferringorloadingoutmaterialsandproduct;•considerplantingvegetationinspecificareastocontroldustflowpatternsandfugitiveemissions;and•identifyandimplementotherimprovementsthatmaybenecessarybasedonpotentialsourcesofparticulateemissions.Thecontingencymeasuresadoptionandimplementationscheduleisasfollows:Tbl4 Ct"a e.onm2encyeasuresop110nanmplemenaIOnc e u e.MAdfd I ltfsh d lActivityCompletionDate{T=triggerdate)1)Evaluatecircumstancesoftrigger;IDsourcesT+1month2)IdentifyadditionalcontrolmeasuresT + 2months3)Facility(s)submitemissioncontrolprogramT+4months4)IssueorderorpermitsT + 6months5)Facility(s)implementadditionalcontrolWithinT +24monthsmeasuresTheemissionscontrolplanforanyfacilityrequiredtosubmitaplanwouldincludethenecessarysupportingtechnicalinformation,emissionscalculations,constructionpermitapplications,andairqualityevaluationtomaketheadditionalcontrolmeasureenforceablethroughtheissuanceof14an order

or construction

permits.

This approach

requires

each affected

facility

to create

and implement

an emissions

control

plan

with targeted

control measures appropriate

to the circumstances

of the situation

that triggered

the contingency

measures. VI. CONCLUSION In 2011,

EPA determined

that

the

SIP

was substantially

inadequate

to maintain

the 2006 24-hour NAAQS

for PM2

. s in the Muscatine

because

monitor

data

area showed violations

of the 2006

24- hour PM2_s standard,

based

upon 2008-2010

data,

and have shown violations

of the standard

in the past.

EPA recognizes

that

the monitoring

value

for

the 24-hour

PM2

. s NAAQS

in Muscatine (for 2011-2013)

is presently

28 Jlg/m

3

. However,

as described

by EPA

in the 2011

SIP

Call

and by Iowa

in the Muscatine

PM2

. s SIP,

the Muscatine

area monitoring

values

have demonstrated

a trend

of fluctuation.

The

SIP

Call

and Iowa's

SIP revision

are intended

to bring permanent

and enforceable

emission reductions

to the Muscatine.

Therefore,

the control strategy

shall

be implemented

even

if the area's monitoring

values continue

to remain

below

the level

of the standard. It

is also significant

to note

that strategies

designed

to reduce

direct

PM2

. s emissions

at GP

C will also reduce emissions

of other

air pollutants.

EPA's

SIP

Call

did

not require multi-pollutant emission reductions,

but

it

is relevant

that

the state's

control strategy

for Muscatine

is projected to have

a beneficial

impact

on other pollutants

of concern

to the public.

As provided

by IDNR, the estimated percentage

reduction

of these

air pollutants

by 2017

are summarized

in Table

5

. Therefore,

based

on

a review

of the state submission,

EPA recommends

proposed

appro

v al of Iowa's

SIP revision

because

it provides permanent

and enforceable

PM2

. s emission reductions

to the Muscatine

area

and improves

the stringency

of the Iowa

SIP. Table

5. Estimated Co-Beneficial

Emissions Reductions

in Emissions

from

2011

to 2017

at GPC* Pollutant

Estimated Percentage

Reduction Sulfur Dioxide

(S02)

84 Hazardous

Air Pollutants

(HAPs)

82** Volatile

Organic Compounds

(VOC)

48 Nitrogen

Oxides

(NOx)

18 Carbon Monoxide

(CO)

13 *These emission

estimates

were provided

by GPC

and have

not been verified

by DNR

. **Reductions

in acetaldehyde

emissions

are included

in this percentage

reduction. Seventy-one

percent

of the reduction

is due

to decreased

Hydrogen

Chloride

(HCl) emissions

from

the coal-fired

boilers. SOURCES

USED Clean

Air Act,

Title

I, Part

A -

Air Quality

and Emissions Limitations h ttp

: // www.e

p a.

g ov

/ air

/ caa/title1

. html Section

1 07,

Air quality

control

regions Section

109, National

ambient

air quality standards 15Section110,ImplementationPlansSection175A,MaintenancePlans40CFRPart50,NationalPrimaryandSecondaryAmbientAirQualityStandardshttp://www.epa.gov/epacfr40/chapt-I.info/chi-toc.htm40CFRPart51,RequirementsforPreparation,Adoption,andSubmittalofImplementationPlanshttp://www.epa.gov/epacfr40/chapt-I.info/chi-toc.htmSubpartA,AirEmissionsReportingRequirementsSubpartF,ProceduralRequirementsSubpartG,ControlStrategySubpartI,ReviewofNewSourcesandModificationsSubpartL,LegalAuthorityAppendixVtoPart51,CriteriaforDeterminingtheCompletenessofPlanSubmissionsAppendixWtoPart51,GuidelineonAirQualityModels40CFRPart52,ApprovalandPromulgationofImplementationPlanshttp://www.epa.gov/region07/air/rules/iowa/iatoc.htmSubpartQ,IowaUSEPAOn-lineStateImplementationPlanProcessingManualhttp://icode.pes.com/sipmanl************************************************************************16