ARIZONA DEPARTMENT OF ENVIRONMENTAL

QUALITY 1110 West Washington

Street• Phoenix, Arizona 85007 (602) 771-2300 ‘www.azdeq.gov Janice

K. Brewer Governor October

4, 2013 Mr. Jared Blumenfeld,
Regional Administrator U.S. Environmental
Protection Agency, Region

IX Mail Code ORA-1 75 Hawthorne

Street San Francisco,

CA 94105 Re: Support Documentation
Regarding

Air Quality Designation

for the Revised National Ambient Air Quality Standard

for Lead Dear

Mr. Blumenfeld: On September

25, 2013,

the Honorable

Janice

K. Brewer, Governor

of Arizona, submitted

a letter

to the U.S. Environmental
Protection
Agency (EPA) recommending

that

the Hayden, Arizona

area

not

be re designated

as nonattainment

for the Revised National Ambient

Air Quality Standard (NAAQS)

for lead. The Arizona Department

of Environmental

Quality (ADEQ)

is submitting

the enclosed Technical Support Document

(TSD)

in support

of that recommendation.

The purpose

of the TSD

is

to describe

the relationship
between

sulfur dioxide
(S02)

and lead concentrations

and demonstrate

the effectiveness

of control technology

in reducing

lead emissions

within

the ASARCO Hayden Copper Smelter. In June 2012, ASARCO completed

the installation

of additional controls

at the facility. ADEQ reviewed the data collected

since

the installation

and determined

that lead concentrations

at the ADEQ Globe Highway monitoring

site have decreased

by approximately

40 percent.

In addition,

there have been

no violations

of the lead standard

since June 2012.

The decrease

in lead concentrations

supports ADEQ’s assertion

that
the area
not

be re-designated

as nonattainment

for the lead NAAQS.

Please

see the attached TSD

for

a detailed analysis. ADEQ respectfully

submits

the enclosed

TSD

as supplemental information

to the Governor’s recommendation

that
the Hayden

area
not

be re-designated

as nonattainment

for the lead NAAQS.

If you have

any questions,

please contact
Steve Calderon,

State Implementation

Plan Section Manager,

at (602) 771-2352.

:7 SncereIy7 Eric C/Massey Dir

tor, Air Quality Enclosure cc: Colleen McKaughan,

EPA Region

IX, w/enclosure Southern Regional

Office 400 West Congress

Street• Suite

433• Tucson,

AZ 85701 (520) 628—6733

Henry

R. Darwin Director Printed

on recycled paper4TechnicalSupportDocumentRelationshipBetweenAmbientSulfurDioxideandLeadConcentrationsHayden,ArizonaArizonaDepartmentofEnvironmentalQualityAugust23,2013

# iflhiiiiiifti 1- 

# Globe Highway

Pb concentrations,

expressed

as 3-month rolling averages,

from January, 2011 through

June, 2013.

The red dashed

line represents

the
Pb NAAQS

of 0.15 jig/rn 3 . April, May, and June data from 2013

are considered preliminary

at this point

due

to incomplete

quality assurance procedures. Previous, unpublished

work conducted

by the Arizona Department

of Environmental Quality

has shown

that

Pb and Sulfur Dioxide

(SO 2 ) concentrations
measured

at the Globe Highway

site

in Hayden,

AZ have

a strong, direct relationship.

This relationship was analyzed

in greater detail

in an attempt

to determine whether control devices installed

at the ASARCO
facility

in July, 2012, have resulted

in reductions

in Pb concentrations
measured

at the Globe Highway

site.

If the reductions

in ambient

Pb concentrations

are

a result

of the installation

of control technologies

that were intended

to Lead (Pb) monitoring

began

at the Globe Highway

site

in January,

2011. With

2.5 years of data having

been collected

thus
far, temporal patterns

in Pb concentrations

have become apparent.

The predominant
signature

in this temporal pattern includes

a maximum

of Pb concentrations

occurring
during

the February through

June time frame. Pb data collected
during

this February through

June period

in 2011

and 2012 showed violations

of the
Pb National Ambient

Air Quality Standard (NAAQS).

During

this same period

in 2013,

the same temporal maximum

has occurred,

but the magnitude

of that maximum

was below

that

of the
Pb NAAQS

(0.15 IgIm 3 ).

This information

is displayed graphically

below

in Figure

1. Based

on the maximum 3-month average

for each calendar

year, ambient

Pb concentrations
measured

at the Globe Highway

site have decreased

by approximately

56% between

2011

and 2013. Since

the installation

of additional controls

in July, 2012, ambient

Pb concentrations

at the Globe Highway

site have decreased

by approximately

40%. 0.3

Globe Highway

Pb Concentrations:

3.month Rolling Averages 0.25 0.2k 0.15CUC 

# o o

0.1.0 

# a. 0.05

0 i_,__

• Month

I YearreducePbemissionsalone,onemayexpecttofindachangeintherelationshipbetweenPbandSO2concentrationsovertime,coincidentwiththeinstallationofthecontroldevices.IfthereductionsinPbconcentrationsweresimplyanartifactofmeteorologicalconditions,onemayexpecttoseesimilardecreasesinSO2concentrations,astherelationshipbetweenthetwopollutantswouldnotchange.Figure2showstherelationshipbetweenambientSO2concentrationsandambientPbconcentrationsmeasuredattheGlobeHighwaystationinHayden,AZbetweenJanuary15th,2011andJune30th,2013.Itisapparentthatthereisastrong,directrelationshipbetweenSO2andPbconcentrationsasbothpollutantsriseandfalltogether.ThecorrelationcoefficientbetweentheSO2andPbdatais0.78,confirmingtheverystrongrelationshipbetweenthetwopollutants.WhilethecorrelationbetweenthePbandSO2dataishigh,Figure2indicatesachangeintherelationshipoccurringaroundJuly,2012,astheseparationbetweentheSO2concentrations(yellowline)andPbconcentrations(blueline)appearstoincrease.Figure2-PbandS02datafromtheGlobeHighwaymonitorsinHayden,ArizonafortheperiodJanuary15,2011toJune30,2013ThisrelationshipwasexaminedfurtherbyexaminingtheratioofSO2concentrationstoPbconcentrationsovertime.Figure3showsthechangeinthisrelationshipmuchclearer.GiventherelativelylargeSO2concentrationscomparedtothatofPbconcentrations,theratioisquitehigh,withSO2concentrationsbeingapproximately263timesthatofPbconcentrationsduringthefirstperiodofthedataseries(Jan15,2011—June30,2012).However,onecanseeaveryabruptchangeintheratio,beginningaroundJuly,2012.TheaverageSO2/Pbratioincreasedsharplyduringthesecondperiodofthetimeseries(July1,2012—June30,2013)withanaverageratioofapproximately719.ThissignificantchangeintheratiobetweenthetwoindicatesasubstantialchangeintherelationshipbetweenPbandSO2concentrationsmeasuredattheGlobeHighwaysite.ThetimingoftheabruptchangeintheSO2toPbratiocoincideswiththeinstallationofGlobeHighwayLeadvsS02=e0.a0Cl,o0000000000000000000000000Date-4.SadditionalcontroltechnologiesthatwasintendedtoreducethePbemissionsfromtheASARCOsmelterfacility.TheSO2andPbdatashowthattheinstallationofthiscontroltechnologyhasbeeneffectiveinreducingthePbconcentrations,relativetopreviouslevels.WhileSO2concentrationsremainelevated,ambientPbconcentrationshavebeenreduced,relativetoPbconcentrationsthatweremeasuredpriortoJuly,2012.AswasshowninFigure1,recentPbdataindicatethatambientPbconcentrationsmeasuredattheGlobeHighwaysitearenowbelowthatofthePbNAAQS.WhileitisbelievedthattheinstalledcontroldeviceswereeffectiveinreducingambientPbconcentrationsinHayden,AZ,additionaldatawouldbeneededtoverifythattheGlobeHighwayPbmonitorcontinuestoattainthePbNAAQS.180016001400aaaaaaaL*j—ra—T.•a—r&aaaaSaaaaaFigure3-TemporalvariationoftherelationshipbetweenSO2andPbasmeasuredbycalculatingtheratiobetweenSO2andPbconcentrations.AnabruptchangeintherelationshipbetweenSO2andPbconcentrationscanbeseenbeginningaroundJuly,2012,whencontroldeviceswereinstalled.2000GlobeHighwayS02!PbRatio(excludeslowS02days<5ug!m3)6004002000aL.——c’1C-4CN4oo00000000000000000CN(N(N(N(N(N(N(N(N(N(N(N(N(N(N(N(N(N—aaa-aaa—(N00—(N—(N—(N—aa-—aa—aa—aaDate