Petition for Writ of Certiorari — Imperial County Air Pollution Control District v. Sierra Club

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FILEC

031334 MAR 17 2004

pr EAICE OF THE CLERK

IN THE

Supreme Court of the United States

IMPERIAL COUNTY AIR POLLUTION

CONTROL DISTRICT, PETITIONER

Vv.

SIERRA CLUB

PETITION FOR A WRIT OF CERTIORARI TO THE

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

PETITION FOR A WRIT OF CERTIORARI

JOHN REESE R. RAYMOND ROTHMAN

BINGHAM MCCUTCHEN LLP Counsel of Record

Three Embarcadero Center MICHAEL S. MCDONOUGH

San Francisco, CA 94111 BINGHAM MCCUTCHEN LLP

(415) 393-2000 355 South Grand Avenue

Suite 4400

RALPH CORDOVA, JR. Los Angeles, CA 90071

County Counsel (213) 680-6400

County of Imperial, California

940 Main Street

Suite 405

E1 Centro, CA 92243

(760) 482-4400

Attorneys for Petitioner

LT a IA aa A ae Se LN a a FA PPOs MN

CURRY & TAYLOR @ WASH D.C. @ (202) 223-3160 ¢ USSCINFO.COM

PO IRONS St LITE |

QUESTIONS PRESENTED

The questions presented in this case are:

(1) whether the Ninth Circuit Court of Appeals’

de novo review of technical findings of fact made by the

Environmental Protection Agency (“EPA”) under

Section 179B(d) of the Clean Air Act (“CAA”), 42

U.S.C. § 7509a(d), in an area of EPA’s special expertise,

can be reconciled with decisions of this Court and the

other federal Circuits; and

(2) whether the Ninth Circuit may rely on that

de novo, lay interpretation of selected facts to mandate

that EPA reclassify the nonattainment area at issue to

“serious” nonattainment under CAA Section 179B(d),

foreclosing further agency consideration.

RULE 14.1 STATEMENT

Petitioner (intervener below) is Imperial County

Air Pollution Control District, a governmental agency

created by state statute as the body with primary

responsibility for the control of air pollution from all

non-motor vehicle sources within Imperial County,

California. Respondent here (petitioner below) is

Sierra Club. Respondent below was EPA.

we hc ert st

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- TABLE OF CONTENTS

QUESTIONS PRESENTED ....ccccsscssssscccssssssssssssssseececooooosecccc... i

RULE 14.1 STATEMENT w.oecccccccsscsccccsssssssssssssssssssssssosssscs.... ii

TABLE OF CONTENTS.............. SEERA ee eo Ree ili

TABLE OF AUTHORITIES ....sssssssssssssssssssssssssseseeseseessssssss... vii

PETITION FOR WRIT OF CERTIORARI cesssssssssssssessssssssss..,.. 1

OPINION AND RULEMAKING BELOW. cessesssssssssssssssssssss...... 1

EIT si satiesttndonhseiveinsusensnenisisiisastesinsveararsanasenc,..< 2

STATUTORY AND REGULATORY PROVISIONS

I icsarraenstactesstrsotesonsnmssencuscstedasoussneseeesonseosonees...... 2

STATEMENT OF THE CASE vesccsssscssscsssscscssssssssestseeeeccoccesss.. 3

A. The CAA Provisions at 18SUC seeeccccscsssseeeecocee..... 3

1. The Particulate Matter N Oe 4

2. CAA Section 179B oo.c..ccesccsssesssssssssseeccoseeeses.... 5

3. EPA Guidance on Section 179B..................... 6

B. Cross-Border Pollution in Imperial

TIEN tlbstirocaihessiontbcnienznsvessbasesinesenasasnessceneesecs 6

C. EPA’s Section 179B IT icititesistisiininstzssateunsars 7

D. The Decision Below .........cccsccsssssssssseeccoseseossss..., 10

REASONS FOR GRANTING THE PETTiION ceeccosoossss-........ 12

ee 12.

THE COURT SHOULD GRANT CERTIORARI

TO CONFIRM THE CORRECT STANDARD OF

REVIEW OF TECHNICAL DECISIONS

ENTRUSTES TO EPA’S EXPERTIES UNDER

CORR TC TIGINE FTO scccecesscossvatirsosicsasannimienonsestiianes 14

A. This Court and the Federal Circuits

Require the Highest Level of Deference

to Agency Decisions Involving

Technical Findings of Fact Within the

Agency’s Special Expertise ...........sccccccscssesese 15

. The Plain Language and Subject Matter

of CAA Section 179B Require the

Greatest Deference to EPA Findings on

Nonattainment Caused by Transborder

SP TNIID sviisssntnininiitidaeconenatinataianisainnadusaiamalaaions 18

. The Court of Appeals Was Required to

Consider the Entire Administrative

Record to Determine if the Finding Was

Adequately Supported .............c.ccccsssssssssssssseees 19

. The Ninth Circuit Failed to Apply the

Required Deference, But Instead

Conducted De Novo Review of Selected

BF Pr Bs iiiiaieiseeiceeteectecrentcee 21

2. Rainfall Data and Receptor Modeling........ 23

i, PN aia ssctiitcinsncitetaceesaceiteciseteienicnanta 24

4. Proximity, Magnitude and Density of

Mexicali PM-10 Emissions vs. Slight

Exxceedances of NAAQS ..........cccsccssssssssscseees 24

E. The Ninth Circuit’s Decision Threatens

Recurring Conflicts on the Scope of

Deference to Expert Agency Findings,

an Issue of National

SINE cnicctnincmiaenaaa ae 25

II. THE COURT SHOULD GRANT CERTIORARI

TO CLARIFY THE CIRCUMSTANCES

UNDER WHICH DISCRETIONARY

TECHNICAL AGENCY DECISIONS MAY BE

REMANDED WITH INSTRUCTION FOR THE

AGENCY TO ENTER A NEW SUBSTANTIVE

RAL ONO cisxovdanicsidbeaabennaaicmmmeealananle 26

SODA IDI .«..:ccicessicissssniensntinniiecaibicaaseaaans maieaaa ee 30

APPENDIX

CIRCUIT COURT ORDER (10/9/2008).........scess00000 la

ORDER DENYING REHEARING .......cccsceseseeseeseees 17a

66 Fed. Reg. 42187 (8/10/01) (and

accompanying EPA Technical Support

Document).............. hs snninenanenionnstpietninesialnnictainiin 20a

66 Fed. Reg. 53106 (10/19/01) ...........eescesceeeseees 65a

59 Fed. Reg. 41998 (8/16/94) ...........sssccssscssessseese 92a

AE Fe OO nicounisiemiiel: 1l6a

AUR Tee, Se ee ae 118a

SE UBC. BIBCTION TOD ascccscccsesnscccnsssisencsssonnsse 129a

42 U.S.C. SECTION T5OQA .......cccrsccocsssocsccesescoses 138a

4B U.S.C. SECTION TRIB vecscesscesvecsvcsesossssnencsnsoees 140a

42 U.S.C. SECTION TBIBA ......cccsccosecsesesescosescsees 144a

BE UTD. SRCTIOIN TOT caseosnenssesssssniianonsivopainianesn 149a

CIRCUIT COURT ORDER (2/10/08)...........s:00e00000 16la

CIRCUIT COURT AMENDED ORDER

Cy a ciastandiciaendnasncaieeledamaeaaa ene 162a

CIRCUIT COURT ORDER (2/21/08) ...........0e000000. 163a

Vii

TABLE OF AUTHORITIES

CASES

1000 FRIENDS OF MARYLAND V. BROWNER, 265

Fe Re Gs TE ierrinencssavincensibanpipbnnemaaiinnintians 16

ALVARADO CMTY. HospP. V. SHALALA, 155 F.3D

1115 (9™ CIR. 1998), AS AMENDED, 166 F.3D 950

Ge I ccsicsnssiseciecnscesichahscnctcectabdeshdeciinashalicaibsbinesiinidencinbicnsinted 29

BALTIMORE GAS & ELEC. Co. v. NATURAL RES.

DEF. COUNCIL, INC., 462 U.S. 87 (1983) .......... 16, 20, 25

BCCA APPEAL GROUP V. EPA, 355 F.3D 817 (5™

III, AE Tt cs dctisenitsehscntcniicebnanapiaeaieiinecsatiae: Nakenmelameonidantadeaammniate 16

BP EXPLORATION & OIL, INC. Vv. EPA, 66 F.3D

ee Se Fe aciatiacieisieanieiinieinienaaavnen 16

CAMP V. PITTS, 411 U.S. 138 (1973) ............cccccccssscscoscsceess 27

CHEVRON, U.S.A., INC. v. NRDC, 467 U.S. 837

Se iiedeccecbicinnahaiieitsaniiii ia octal tal ii 21, 22, 23, 25

CITIZENS TO PRESERVE OVERTON PARK V.

VOLPE (“OVERTON”), 401 U.S. 402 (1971) ............. eee 15

CITY OF ALBUQUERQUE V. BROWNER, 97 F.5D

415 (10™ Cir. 1996), CERT. DENIED, 522 U.S. 965

CEES eceeiinsnininsctssncnssnnnebeanesiiaiindacanieiapsisinialintiiaiadinianaiiaiinia 16

CITY OF WAUKESHA V. EPA, 320 F.3D 228 (D.C.

its TE cheess-cuscisaticschsbuslcanaclbcnienaaasecanaiacueieaaaidaadanecaelincaante 16

Vili

COUNTY OF LOS ANGELES V. SHALALA, 192 F.3D

1005 (D.C. CIR. 1999), CERT. DENIED, 530 U.S.

ee ae: 28

DAVIS V. EPA, 348 F.3D 772 (9™ CIR. 20038) ..........0000000 16

DIA V. ASHCROFT, 353 F.3D 228 (8D CIR. 2008).............. 28

ETHYL Corp. Vv. EPA, 541 F.2D 1 (D.C. Cir.),

CERT. DENIED, 426 U.S. 941 (1976) ............ccccccsssccseseeees 17

EXXON MOBIL CorpP. V. EPA, 217 F.3D 1246 (9™

aN IER TE RT RT Ta I ETE 15

FCC v. NAT. CITIZENS COMM. FOR

BROADCASTING, 436 U.S. 775 (1978) ......ccccccccssssssssescees 25

FEDERAL POWER COMW’N V. FLORIDA POWER &

LIGHT Co., 404 U.S. 453 (1972)............cecsceeee 15, 16, 17, 25

FLORIDA POWER & LIGHT Co. Vv. LORION, 470

Fas Se CP csisciibcscideiieniseniceeeaesniiaiaialelgiiediuisbiadaibianileaitie 27

GOODYEAR TIRE & RUBBER Co. V. DEPT. OF

ENERGY, 118 F.3D 1531 (FED. CIR. 1997)..............00000 17

INS v. AGUIRRE-AGUIRRE, 526 U.S. 415 (1999) ........... 19

INS V. CHEN, 587 U.S. 1016 (2002)..........cccccsscccscossesccsecees 26

INS v. ELIAS-ZACARIAS, 502 U.S. 478 (1992)............000. 26

INS v. VENTURA, 587 U.S. 12 (2002)............cccsscssessees 28, 29

JAHED V. INS, 356 F.3D 991 (9™ CIR. 2004)... eeeeeeeee 26

ERY

KROGER Co. V. REGIONAL AIRPORT AUTH. OF

LOUISVILLE AND JEFFERSON COUNTY, 286

Fe is IE itiniiseiebneniptiniasntainginamenintianeiian 28

MARSH V. OREGON NATURAL RES. COUNCIL, 490

Fac EH Ce iainiiessecescitiaaniaictdaavintlbnnaivuiitciaiin 16, 16, 25

MICKEVICIUTE V. INS, 327 F.3D 1159 (10™ Cir.

SPEIE sussth:cdicaesocaneavinsandeigapakcsacdaaidiamacamtiaaaamialeaasuinnad 28

NEW YORK V. EPA, 716 F.2D 440 (7™ CIR. 1988)........... 16

NRDC v. MUSZYNSKI, 268 F.3D 91 (2D CIR. 2001)......... 16

PENSION BENEFIT GUARANTY CorpP. V. LTV

CORP, 496 UB. GBS CGO) avccecescscnerccsssssescesosescsvsvecs 26, 27

PUERTO RICO AQUEDUCT & SEWER AUTH. V.

EPA, 35 F.3D 600 (15" CIR. 1994), CERT. DENIED,

Be is Se EE Wickiicnetineinkiaraiieebanne 16

SEAVEY V. BARNHART, 276 F.3D 1 (1°" Cir. 2001).......... 28

SEC v. CHENERY CorpP., 318 U.S. 80 (1948)............. 15, 27

SIERRA CLUB V. EPA, 346 F.3D 955 (9™ CIR.),

MODIFIED, 352 F.3D 1186 (2003)............cccssceecceseees passim

SIERRA CLUB V. EPA, 311 F.3D 853 (7™ Cir.

rTIET sic eskieiclsbibeileenaticediieibeiitaaiadiaenasdaalaladstamcaaammmeansmnuniatia 29

SMOLEN V. CHATER, 80 F.3D 1273 (9™ CIR. 1996).......... 29

SOUTHWESTERN PA. GROWTH ALLIANCE V.

BROWNER, 121 F.3D 106 (8D CIR. 1997) wu... ee eeeeeee 16

SUNSHINE STATE BANK V. FDIC, 783 F.2D 1580

CE, Te esicninticthccpsebsvebecsoteblianiiaisinrensntaiieenasaiieininn 16

UNITED STATES POSTAL SERVICE V. GREGORY,

BT Fe, Fe pee ciaisnitssnendcastanensennionnicatnnasnesiininannianeniin 16

U.S. v. BP Amoco OIL PLC, 277 F.3D 1012 (8™

Cir. 2002), CERT. DENIED, DICO, INC. Vv. U.S.,

BST U.S. 942 (Z0GZ) rvveroresressrssensncnovcsscnvssosssseseosevevenseees 15

UNIVERSAL CAMERA Corp. V. NLRB, 340 U.S.

BFE CRBS) cecescersecrsecsssorescssenecosnenqquensvesnsvevonnvenstarcooveseenereth 20

WARD V. BROWN, 22 F.3D 516 (2D CIR. 1994)..........s0e000 28

WEST VIRGINIA HIGHLANDS CONSERVANCY,

INC. V. NORTON, 343 F.3D 239 (4™ CIR. 2008)........000008 28

OTHER AUTHORITIES

By ET BB. § BG scensssseosincnersosonpsisenssnnsssonsenessounesesnmnvesennennetons 19

5 UBC. 8 FOC 2 AD ocecsenccessrensonsresscnnsvnssensconronessnereinonsetevone 15

SB-U B.C. $ TEES) ccrccessesesecvevvesioeensnvsnevensncarsrepssnessonponevonesee 2

AZ UBC. § TAG) sccssrvorsessscrsessesccovonsrevsenionssnscnesvenssoonees 3,4

AZ U.S.C. § T4OWH A) ncrrcrccserercccssovesassoscossevaneesosesssssosveosenneosese 2

4D US S.C. § TOOZLD) weccscsececsccosesscccennscersssonscnncnsssssssvoossoessosves 2

42 U.S.C. $ TBC C) vecesescsesvscoresecesescossoseovesseessonsesoensosssssossenese 2

BB UL BC. © TR vncneicicetcswnecineiinnnsminvivnseisninnseninmmesn passim

42 U.S.C. § TB1S ....cccccoccsosesesersscsosccoscccsooosssessesssosscssassenscesses 2

ee SEK ee Retin hatin.

a Sts Dh PO ni diccsinsiienciiitbpssiesnccibabiniteniiticoadaddiiataibedcaamaes 2

Be Seats FS OR sictntesnasionsnusibinbossaisinaidainsoiilasadaaaiamaianaaa 15

ee abe bei uiescsnstiiinsnssoncisibensccleaeintiaesiccaanialallaintitua 2%

Ae ae We diane iise ideas eit pceeneiaaaaadclbaeiad 2

09 Fed. Reg. 41998 (Aug. 16, 1994)...........c.ccccscssssssesceees 2,5

66 Fed. Reg. 53106 (Oct. 19, 2001) sessennnnnnsssssesecnnnanssssssesssnee

66 Fed. Reg. 42187 (Aug. 10, 2001) (and

accompanying EPA Technical Support

| ER Oe A ee a OTE a: 2,3

136 Cong. Rec. S2584, S2587 (daily ed. Mar. 9,

| Sn dial anheneR animes 19

H.R. Rep. No. 490(1), 101** Cong., 2d Sess. 262-70

Se ein escanscsrusnectvericaancasililindinenaaiitasananaieiasintenasianblinnnintl 5

PETITION FOR WRIT OF CERTIORARI

Imperial County Air Pollution Control District

(“the District”) petitions for a writ of certiorari to

review the judgment of the United States Court of

Appeals for the Ninth Circuit. In that decision, the

court, in a single paragraph, and based on de novo

review of a single piece of evidence from a well-

supported technical administrative record, rejected

EPA’s fact findings and substituted its own conclusion

that foreign emissions could not possibly have caused

two PM-10 NAAQS! exceedances of 12 and 25

micrograms per cubic meter of air, The court further

remanded with instructions that EPA reclassify

Imperial County to “serious” nonattainment,

foreclosing additional EPA consideration. The decision

directly conflicts with this Court’s decisions mandating

the highest deference to EPA’s technical fact findings.

If left in place, it will not only directly conflict with

decisions of this Court and every Circuit, but will

impose staggering burdens on the County, its economy

and tens of thousands of largely low-income residents

who rely on that economy for survival.

OPINION AND RULEMAKING BELOW

The court of appeals’ opinion, Sierra Club v.

United States Environmental Protection Agency, is

reported at 346 F.3d 955 (9 Cir. 2003). App. la-16a.

The decision was modified and rehearing was denied on

December 18, 2003, and reported as Sierra Club v.,

EPA, 352 F.3d 1186 (9 Cir, 2003), App. 17a-19a, The

Ninth Circuit’s orders requesting supplemental briefing

| “PM-10” refers to particulate matter of ten microns in diameter

or less. “NAAQS” refers to the National Ambient Air Quality

Standards.

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are reproduced at App. 161a-1638a.

The EPA rulemaking at issue was issued in two

parts. The final rule was reported at 66 Fed. Reg.

53106 (Oct. 19, 2001). App. 65a-91a. The proposed rule

was reported at 66 Fed. Reg. 42187 (Aug. 10, 2001)

(App. 20a-47a), and also referenced an August 10, 2001

Technical Support Document prepared by EPA in

connection with the proposed rule (App. 48a-64a).

JURISDICTION

The jurisdiction of this Court is invoked under 28

U.S.C. §1254(1), The court of appeals entered

judgment on October 9, 2003, and amended that

judgment on December 18, 2003, Also on December 18,

2003, the court of appeals denied the District’s petition

for rehearing, but granted the District’s motion to stay

the mandate until March 17, 2004, or if a petition for

certiorari is filed, until final disposition by this Court.

App. 17a-18a.

STATUTORY AND REGULATORY

PROVISIONS INVOLVED

The statutes involved are 42 U.S.C.

§§ 7407(d), 7409(a), 7502(b) & (c), 7509a, 7513, 7513a and

7607. They appear verbatim at App. 118a-160a.

The regulations involved are 40 C.F.R. § 50.6, 66

Fed. Reg. 53106 (Oct. 19, 2001), 66 Fed. Reg. 42187

(Aug. 10, 2001) (and accompanying EPA Technical

Support Document) and 59 Fed. Reg. 41998 (Aug. 16,

1994). Section 50.6 of 40 C.F.R. appears verbatim at

App, 116a-117a, A verbatim version of the relevant

sections in 59 Fed, Reg, 41998 (Aug, 16, 1994) (pages

41998-42002 only) appears at App, 92a-11ba, As

referenced above, 66 Fed, Reg, 58106 (Oct, 19, 2001), 66

Fed. Reg. 42187 (Aug. 10, 2001) and the Technical

Support Document appear verbatim at App. 20a-91a.

STATEMENT OF THE CASE

A. The CAA Provisions at Issue

1. The Particulate Matter NAAQS

In 1990, Congress amended the CAA to

emphasize states’ primary responsibility to regulate

sources of air pollution within their borders. Under

CAA Section 109(a) (42 U.S.C, § 7409(a)), EPA adopted

NAAQS for certain air pollutants, including PM-10,

EPA adopted two PM-10 NAAQS; a maximum 24-hour

concentration of 150 micrograms per cubic meter

(“ne/m*”’) (the “24-Hour Standard”) and a maximum

annual arithmetic mean concentration of 50 g/m" (the

“Annual Standard”), 40 C.F.R. § 50.6(a), (b). The 24-

Hour Standard is attained when the expected number

of days per calendar year exceeding that standard is no

more than one. Jd. § 50.6(a). The Annual Standard is

attained when the expected annual mean PM-10

concentration is no more than 50 pg/m*. Id. § 50.6(b).

Areas not meeting the PM-10 NAAQS initially

(including Imperial County) were designated as

“nonattainment” for PM-10 (42 U.S.C. § 7407(d)), and

were initially classified as “moderate” PM-10

nonattainment areas (id. § 7513(a)).

States with PM-10 nonattainment areas were

required to submit to EPA a state implementation plan

(“SIP”) demonstrating how the state proposes to meet

the PM-10 NAAQS by a specified “attainment date,”

Id, 8§ 7410(a); 7502(b), (c), The attainment date for

moderate PM-10 areas was December 31, 1994, /d,

§7518(¢)(1), If EPA finds the area failed to attain the

PM-10 NAAQS by this attainment date, the area is

subject to reclassification to “serious” PM-10

nonattainment, which requires, among other things,

that the area be subject to rigorous and expensive

implementation of “best available control measures” for

all source categories in the area. Jd. §§ 7513(b)(2),

7513a(b)(1)(B).

| 4 CAA Section 179B

Congress also determined that nonattainment

areas should not be penalized with reclassification if

nonattainment is caused by pollution sources outside

the United States, codifying this protection in CAA

Section 179B, added as part of the 1990 CAA

Amendments. See 42 U.S.C. § 7509a(d), Section

179B(d) provides:

Notwithstanding any other provision of

law, any State that establishes to the

satisfaction of the [EPA] Administrator

that, with respect to a PM-10

nonattainment area in such state, such

State would have attained the [PM-10

NAAQS] by the applicable attainment

date, but for emissions emanating from

outside the United States, shall not be

subject to the provisions of section

7513(b)(2) of this title [mandating

reclassification of area].

Thus, Section 179B invests EPA _ with sole ,

responsibility to evaluate and address the impacts and |

domestic consequences of cross-border pollution, and

prohibits reclassification if EPA finds nonattainment is

due to cross-border impacts,

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The legislative history indicates that Congress

was well aware of the chronic cross-border pollution

impacting U.S. border areas, including Imperial

County. See H.R. Rep. No. 490(I), 101* Cong., 2d Sess.

262-70 (1990) (recognizing “problem” of “transboundary

emissions” in four border areas: Douglas, Arizona;

Calexico, California [in Imperial County]; Nogales,

Arizona; and El Paso, Texas). Congress adopted

Section 179B(d) specifically to give EPA the flexibility

and sole authority to address threats to attainment

status posed by cross-border pollution. Jd.

3. EPA Guidance on Section 179B

EPA promulgated regulations regarding the

types and amount of evidence sufficient to satisfy EPA

that, but for foreign emissions, a PM-10 nonattainment

area would have timely attained the PM-10 NAAQS.

See 59 Fed. Reg. 41998, 42000-02 (Aug. 16, 1994)

(“Section 179B Guidance” or “Guidance”) [App. 92a-

115a].

The Section 179B Guidance provided that

“Ts]everal types of information may be used to evaluate

the impact of emissions emanating from outside the

U.S.” App. 104a (emphasis added). EPA outlined five

examples of such information: (1) comparing PM-10

monitoring readings with wind and _ other

meteorological data, (2) showing that reasonably

controlled U.S.-side PM-10 emissions do not cause

NAAQS exceedances, (3) analysis of ambient PM-10

sample filters, (4) comparison of the magnitude of U.S.

and foreign PM-10 emissions sources, and (5) air

dispersion and/or receptor modeling to compare US.

and foreign emission impacts. App. 104a-105a

The Guidance notes that these example methods

are neither required nor exclusive, and one category of

information is not superior to another. “The State may

use one or more of these types of information or other

techniques, depending on their feasibility and

applicability, to evaluate the impact of emissions

emanating from outside the U.S. on the nonattainment

area.” App. 104a. EPA considers this information on a

case-by-case basis in determining whether the

protections of Section 179B should apply. Id.

B. Cross-Border Pollution in _ Imperial

County

Imperial County is a rural county with a

population of over 142,000, located in the southeastern

corner of California. App. 2a-3a. The District has

primary responsibility for regulating air pollution from

stationary sources in Imperial County. App. 3a. As the

District explained in its brief to the Ninth Circuit

below, agriculture comprises the majority of the

County’s non-governmental economy, and the County’s

residents — 65% of whom are minorities and nearly a

quarter of whom live below the poverty line - depend

heavily on this agricultural industry for their livelihood.

The County shares over 80 miles of its border

with Mexico, and directly adjoins the highly urbanized

city of Mexicali, Mexico - a densely populated

metropolitan area of nearly one million people. ER 88?

Because of this proximity, as Congress _ itself

recognized, Imperial County regularly receives massive

amounts of pollution from Mexican sources. App. 29a-

30a. The magnitude of cross-boundary PM-10 transport _

is undeniable. In Mexicali alone — a city covering only

200 square miles - PM-10 emissions are at least 11 tons

2 “PR” refers to Petitioner’s Excerpts of Record in the matter

below.

per day greater than all PM-10 emissions over the

entire 4,060 square mile area of Imperial County. App.

29-30a, 79a. This equates to an emissions density 20

times greater in Mexicali than in all of Imperial County.

Prevailing wind and vehicle traffic patterns near the

border combine to transport these PM-10 emissions

from Mexicali into Imperial County. ER 99-105.

While the existence of the cross-border

emissions problem is not seriously disputed, precisely

quantifying the scope of this problem has proved

daunting. For the past decade, the District has worked

with EPA, the California Air Resources Board

(“CARB”) and Mexican authorities in an attempt to

inventory emissions sources on both sides of the border,

quantify cross-border emissions, and implement

appropriate controls. See ER 90-92, 98. However, the

historical data are incomplete, and gathering

information on Mexican emissions sources has required

sensitive diplomatic negotiations between EPA and

Mexican agencies to obtain reliable data. Id. The

District conducted additional technical analyses to

supplement the incomplete data from Mexico, to better

document the fact that the County would have attained

the PM-10 NAAQS by December 31, 1994 but for PM-

10 influence from Mexico. ER 88, 90-92, 98.

C. EPA’s Section 179B Finding

In September 2000, Sierra Club filed suit

seeking to compel EPA to reclassify Imperial County to

“serious” PM-10 nonattainment. App. 6a. Under a

settlement agreement between EPA and Sierra Club,

EPA agreed to take one of three actions by October 9,

2001: find the County to be in PM-10 attainment,

reclassify the County to “serious” PM-10

nonattainment, or find under CAA Section 179B that

the County would have attained the PM-10 NAAQS by

the December 31, 1994 attainment date but for

emissions emanating from Mexico. Id.

In July 2001, the District and CARB submitted

to EPA the “Imperial County PM-10 Attainment

Demonstration” (“Demonstration”), documenting that

the County would have timely reached PM-10

attainment but for Mexican emissions. See ER 85-134;

Supp. ER 19-108. The Demonstration addressed the

seven days during the statutory attainment period

(1992-1994) with recorded exceedances of the 24-Hour

Standard, as measured at various monitoring locations

in Imperial County.* Id. These exceedances were

relatively slight; except for a reading of 258 pg/m’ on

August 6, 1994, all of the exceedances were within 3-32

micrograms of the Standard. App. 53a-59a. The

Demonstration documented, based on multiple types of

evidence, that none of the measured exceedances would

have occurred but for the influence of transborder PM-

10 emissions from Mexico. See App. 24a-33a, 48-64a;

ER 105-07.

EPA carefully reviewed the Demonstration and

other supporting data submitted by the District,

’ “Supp. ER” refers to EPA’s Supplemental Excerpts of Record

below.

4 The recorded exceedances of the 24-Hour Standard (150 pg/m*)

were on January 19, 1993 (162 pg/m* at the Brawley monitor);

January 25, 1993 (175 pg/m* at Brawley); August 23, 1993 (166

g/m’ at El Centro); July 7, 1994 (165 g/m’ at Calexico-Grant St.);

August 6, 1994 (258 pg/m* at Calexico-Ethel St. and 182 pg/m* at

Calexico-Grant St.); October 17, 1994 (159 pg/m* at Calexico-Grant

St.); and December 16, 1994 (153 pg/m* at Calexico-Ethel St.). See

App. 53a-59a.

separately analyzing and addressing each of the seven

exceedance days. App. 24a-33a, 48-64a. On August 10,

2001, EPA found under CAA Section 179B that the

Demonstration adequately established none of the

1992-1994 exceedances would have occurred but for

emissions from Mexico. App. 24a-25a. However, to

allow for the possibility that public comments could

persuade EPA to change its mind, EPA invited public

comment on two alternative proposed findings: (a) a

finding of PM-10 nonattainment and reclassification to

“serious,” or (b) a finding under that the County would

have timely attained the PM-10 NAAQS but for

emissions emanating from Mexico. See App. 20a-64a

(the “Proposed Finding”). In the Proposed Finding,

EPA applied the Section 179B Guidance and found that

the Demonstration contained sufficient evidence under

Methods 1, 4 and 5 to support a finding that none of the

seven exceedances would have occurred but for the

influence of Mexican emissions. App. 24a-33a.

During the public comment period, the District

provided further evidence that each exceedance would

not have occurred but for transborder emissions. See

District’s “Comments on Proposed Finding of

Attainment in Imperial County, CA But For Foreign

Emissions” (“District. Comments”) (incorporated into

the administrative record at ER 191). The additional

data showed that the January 19 and 25, 1993

exceedances were the only recorded PM-10

exceedances ever occurring in the wet winter months

(Nov.-Feb.) in eight years of monitoring in Imperial

County. Id. at 12-17. The data also documented that

extremely heavy rainfall in the County immediately

before the January 19 and 25 exceedances would have

suppressed local PM-10 sources to such an extent that

they could not have caused the exceedances, and that

the numbers either were monitoring errors or were due

to cross-border emissions. Id.

On October 19, 2001, EPA issued its final rule

finding that the record adequately demonstrated that,

but for emissions from Mexico, Imperial County would

have timely attained the PM-10 NAAQS. App. 65a-9la

(the “Finding”). All of the public commenters

supported the Finding except for Sierra Club. App.

69a. Even so, EPA fully considered and rejected Sierra

Club’s argument that the evidence was inadequate to

support the Finding as it applied to the January 19 and

25, 1993 exceedances. App. 69a-82a.

D. The Decision Below

Sierra Club petitioned the Ninth Circuit to

overturn the Finding, repeating its argument that the

evidence was insufficient to support the Finding. App.

8a, 10a-lla. After oral argument, the court ordered

supplemental briefing on, among other things, whether

the January 19 and 25, 1998 exceedances would not

have occurred but for influence from cross-border

emissions. App. lla-12a. Sierra Club alleged that

westerly and _ west-southwesterly components in

windroses for these days foreclosed any possibility that

transborder emissions influence could have caused the

measured exceedances. App. 10-12a. EPA and the

District countered that the variable near-border winds

on those days also showed clear components from the

southern half of the compass, and that when the

available wind data was read together with the rest of

the evidence, the totality of evidence adequately

supported EPA’s Finding that these slight exceedances

would not have occurred but for emissions from Mexico.

See App. 12a.

The court reversed and remanded EPA’s

Finding with directions to reclassify Imperial County

as a “serious” nonattainment area. App. 12a-14a. While

it purported to recognize that a deferential standard of

review was required, the court actually applied a

selective, de novo review of the January 19 and 25, 1993

exceedances. See App. 12a-13a. The court focused only

on windrose data, failing to cite any of the other

evidence in the record (e.g., windspeed, rainfall,

geographic characteristics of county, magnitude of PM-

10 emissions, slight magnitude of the exceedances, etc.)

bearing on whether the exceedances on January 19 and

25 would have occurred without influence from Mexican

emissions. /d.

The court supplanted EPA’s assessment of the

data with its own lay analysis, concluding that “EPA’s

notion of what constitutes a southerly wind in the

windroses is, at the least, expansive and, at most,

positively incorrect.” App. at 12a. The court further

asserted, without explanation, that such winds “of the

west-southwesterly variety . . . do[] not support the

theory of transport from Mexico.” App. 18a.

Concluding that the Finding “{ran] counter to the

evidence” before EPA, the court observed that, based

on its own assessment of “the data and reports in the

record, there simply is no possibility that Mexican

transport could have caused the observed PM-10

exceedances on January 19 and 25.” Jd. The court then

ordered that the case be remanded to EPA with

instructions to reclassify Imperial County as a “serious”

nonattainment area. App. 14a.

The District petitioned for rehearing and moved

to stay the mandate pending filing of this petition. The

court of appeals denied rehearing, but granted the

motion for stay. App. 18a-19a.

REASONS FOR GRANTING THE PETITION

Summary of Argument

i The decision below is an abrupt departure

from decisions of this Court and the federal Circuits

regarding the scope of review of EPA technical findings

within its special expertise. By substituting its own lay

“fact-finding” for a critical decision entrusted to EPA’s

technical expertise, the Ninth Circuit fashioned a new

doctrine that would allow courts to hand-pick selected

data from an agency rulemaking record, disregard the

agency’s findings and apply a de novo interpretation of

the data in a context divorced from the agency’s

detailed and nuanced review. This doctrine cannot

coexist with the decisions of this Court and the federal

Circuits.

This is a case of first impression in a sensitive

area of the CAA defining EPA’s authority to evaluate

the domestic impacts of foreign pollution. CAA Section

179B(d) strikes a delicate balance among federal

regulation of ambient air, state implementation of the

federal scheme, and _ international coordination

regarding the transport of air pollutants. It requires

highly complex scientific review of the available, often

incomplete data sets and the application of EPA’s

technical expertise as to the probable source of ambient

air pollution near the border.

The decision below is flatly inconsistent with the

plain language of Section 179B. Section 179B(d)

specifies the highest possible level of flexibility and

BARR NR ee Ooo To Sv

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discretion for EPA; a state need only prove “to the

satisfaction of the [EPA] Administrator” that

nonattainment was caused by transborder influence. 42

U.S.C. § 7509a(d). Instead, the decision below gives

only lip-service to deferential judicial review, and

effectively rewrites Section 179B(d) to force states to

predict what evidence a reviewing court (using a lay

analysis) would require to show that nonattainment is

due to transborder emissions. This renders EPA’s

review and consideration irrelevant, and upends the

spirit and letter of Section 179B.

These are recurring issues of national

importance, impacting every federal agency with

delegated authority to make _ discretionary

determinations within their specialized expertise. This

Court should grant certiorari to preserve the

independence of EPA and other agencies to make

expert decisions without unwarranted judicial

interference.

2. This Court and the federal Circuits have

long held that, when a reviewing court vacates an

agency decision on the grounds that it is not rationally

supported by the record, the decision should be

remanded for further proceedings at the agency level.

This rule respects the agency’s role as fact finder and

gives it an opportunity to evaluate the evidence in

support of its action, or to modify its decision to

conform to the evidence.

In conflict with this precedent, the Ninth Circuit

instead remanded with instructions for EPA to adopt a

rule reclassifying Imperial County to “serious”

nonattainment, based on the court’s incorrect de novo

conclusion that “there simply is no possibility that

Mexican transport could have caused the observed PM-

10 exceedances on January 19 and 25.” App. 18a. Thus,

the court compounded its factual error by denying EPA

any further opportunity to address the matter. This

was wrong as a matter of law, and it imposed

staggering and unacceptable burdens on the County

and District.

Again, this decision implicates recurring and

important issues; it threatens the traditional authority

of EPA and other federal agencies to make factual

findings and policy decisions delegated by Congress to

the agency’s expertise.

I. THE COURT SHOULD GRANT CERTIORARI

TO CONFIRM THE CORRECT STANDARD OF

REVIEW OF TECHNICAL DECISIONS

ENTRUSTED TO EPA’S EXPERTISE UNDER

CAA SECTION 179B

The Ninth Circuit’s de novo assessment of the

technical meaning of the January 19 and 25, 1993 data,

divorced from the rest of the administrative record,

directly conflicts with decisions of this Court and the

federal Circuits on the broad judicial deference to

which expert agency decisions are entitled. These

decisions are uniform: discretionary agency decisions

made within the agency’s special technical expertise are

entitled to the highest level of deference by reviewing

courts. They may not be discarded in favor of the

court’s lay conclusions. This should be particularly so

where, as here, the underlying statute makes clear

Congress’ intent to empower the agency with the

broadest discretion in an area.

The plain words and the legislative history of

CAA Section 179B mandate maximum flexibility for

;

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EPA to address nonattainment issues in the sensitive

context of international emissions impacts. The

decision below would eliminate this flexibility and

rewrite Section 179B to allow de novo judicial review of

the facts. Legitimate EPA policy choices, made after

careful consideration of complex and _ incomplete

information, could be undone by a circuit court sitting

as a super-agency with its own technical interpretations

of the facts and opinions about cross-border emission

impacts.

A. This Court and the Federal Circuits

Accord the Highest Level of Deference

to Agency Decisions Involving Technical

Findings of Fact Within the Agency’s

Special Expertise

Sixty years of this Court’s jurisprudence leave

no question that agency actions on matters entrusted

by law to its discretion are entitled to substantial

deference by a reviewing court. See 5 U.S.C.

§ 706(2)(A) (agency decision may be reversed only if

arbitrary, capricious or not in accordance with law); see

also United States Postal Service v. Gregory, 534 U.S.

1, 7 (2001); Marsh v. Oregon Natural Res. Council, 490

U.S. 360, 377 (1989); Federal Power Comm’n v. Florida

Power & Light Co. (“FPC”), 404 U.S. 458, 463 (1972);

Citizens to Preserve Overton Park v. Volpe (“Overton”),

401 U.S. 402, 416 (1971); SEC v. Chenery Corp., 318

U.S. 80, 88 (1943). A discretionary EPA rulemaking

action under 42 U.S.C. Section 7607(b)(1) is among

those actions entitled to judicial deference; it may be

vacated only if “arbitrary, capricious, or contrary to law

or if it exceeds the statutory jurisdiction, authority, or

limitations.” Exxon Mobil Corp. v. EPA, 217 F.3d

1246, 1248 (9 Cir. 2000).

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In reviewing whether an agency’s decision is

“arbitrary or capricious,” a court may not reweigh the

facts and come to its own conclusions. See Baltimore

Gas & Elec. Co. v. Natural Res. Def. Council, Inc., 462

U.S. 87, 105 (1983). “It is not our task to determine

what decision we, [in the agency’s position], would have

reached. Our only task is to determine whether the

[agency] has considered the relevant factors and

articulated a rational connection between the facts

found and the choice made.” Baltimore Gas, 462 U.S, at

105.

Moreover, an agency’s scientific determinations

within its special area of expertise receive the absolute

highest level of deference.’ See Marsh, 490 U.S. at 377,

Baltimore Gas, 462 U.S. at 103; FPC, 404 U.S. at 468.

’ Decisions from every Circuit facing the issue are in accord on

granting this extreme deference to EPA’s technical findings within

its expertise. See, e.g., City of Waukesha v. EPA, 320 F.3d 228, 247

(D.C. Cir. 2003) (“[W]e will give an extreme degree of deference to

the agency when it is evaluating scientific data within its technical

expertise.” (internal quotation marks omitted)); Puerto Rico

Aqueduct & Sewer Auth. v. EPA, 35 F.3d 600, 604 (1* Cir. 1994),

cert. denied, 513 U.S. 1148 (1995); NRDC v. Muszynski, 268 F.3d

91, 101 (2d Cir. 2001); Southwestern Pa. Growth Alliance v.

Browner, 121 F.3d 106, 117-18 (8d Cir. 1997); 1000 Friends of

Maryland v. Browner, 265 F.3d 216, 236-37 (4% Cir. 2001); BCCA

Appeal Group v. EPA, 355 F.8d 817, 824 (5 Cir. 2003); BP

Exploration & Oil, Inc. v. EPA, 66 F.3d 784, 792 (6 Cir 1995);

New York v. EPA, 716 F.2d 440, 444 (7 Cir. 1983); U.S. v. BP

Amoco Oil PLC, 277 F.3d 1012, 1019 (8 Cir. 2002), cert. denied,

Dico, Inc. v. U.S., 5387 U.S. 942 (2002); Davis v. EPA, 348 F.3d 772,

781 (9 Cir. 2003); City of Albuquerque v. Browner, 97 F.3d 415,

427 (10 Cir. 1996), cert. denied, 522 U.S. 965 (1997). Accord

Sunshine State Bank v. FDIC, 783 F.2d 1580, 1582-83 (11 Cir.

1986) (deference to FDIC Board); Goodyear Tire & Rubber Co. v.

In FPC, the Court advised reviewing courts to

accord maximum deference to such expert technical

decisions:

A court must be reluctant to reverse

results supported by such a weight of

considered and carefully articulated

expert opinion, Particularly when we

consider a purely factual question within

the area of competence of an

administrative agency created by

Congress, and when resolution of that

question depends on ‘engineering and

scientific’ considerations, we recognize the

relevant agency’s technical expertise and

experience, and defer to its analysis

unless it is without substantial basis in

fact.

Id. at 463; see also Ethyl Corp. v. EPA, 541 F.2d 1, 36

(D.C. Cir.) (court reviews an agency’s scientific

judgments “not as the chemist, biologist, or statistician

that we are quelified neither by training nor experience

to be, but as a reviewing court exercising our narrowly

defined duty of holding agencies to certain minimal

standards of rationality.”), cert. denied, 426 U.S. 941

(1976).

Dept. of Energy, 118 F.3d 1531, 1536 (Fed. Cir. 1997) (to Dept. of

Energy).

B. The Plain Language and Subject Matter

of CAA Section 179B Require the

Greatest Deference to EPA Findings on

Nonattainment Caused By Transborder

Emissions

In addition to this extremely high level of

deference to technical findings of agencies, the plain

language of Section 179B itself requires still further

deference to EPA attainment determinations involving

evaluation of international emissions impacts. Section

179B provides that the evidence need only show “to the

satisfaction of the Administrator” that the area would

have timely attained the NAAQS but for foreign

emissions, 42 U.S.C. § 7509a(d).

The justification for this enhanced level of

agency discretion is clear from the legislative history of

Section 179B. Congress recognized that a finding of

attainment “but for” foreign emissions is more than a

bare technical decision; it also involves both a domestic

and foreign policy judgment as to whether U.S. areas

will be required to take strict measures to address

near-border pollution not originating from those areas.

Senator Gramm, one of the sponsors of the amendment

adding Section 179B, emphasized that the amendment

was intended to ensure that EPA retained

responsibility for addressing international pollution,

and that it would have the flexibility necessary to do so:

[Cross-border pollution] is an

international! problem that has to be dealt

with separately .. . [States] will have an

opportunity to come to EPA and say that

they are in compliance in terms of their

emissions, that their failure to meet the

overall standards is due to something that

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is happening in a sovereign foreign

country over which they exercise no

control. This amendment will give EPA

the flexibility to address that problem.

136 Cong. Rec. S2584, S2587 (daily ed. Mar. 9, 1990)

(statement of Sen. Gramm).

Section 179B reflects Congress’ intent to provide

EPA this maximum flexibility. By permitting EPA to

act on evidence establishing to its “satisfaction” that

nonattainment is caused by transborder emissions,

Section 179B plainly invests EPA with the greatest

possible discretion to assess such evidence and make

the technical conclusions that flow from it.

Indeed, EPA decisions under Section 179B

necessarily involve an added layer of complexity, in

that they occur at the intersection of domestic

environmental policy and international relations, areas

in which this Court has accorded the greatest deference

to federal agencies. See INS v. Aguirre-Aguirre, 526

U.S. 415, 425 (1999). Allowing a reviewing court to

make its own lay assessments of selected data

concerning international emissions impacts would

thwart Congress’ intent and ignore Section 179B(d)’s

plain language.

C. The Court of Appeals Was Required to

Consider the Entire Administrative

Record to Determine if the Finding Was

Adequately Supported

Finally, it is equally clear that a reviewing court

must look at the entire administrative record before

determining whether the agency’s decision is supported

by the evidence. See 5 U.S.C. § 506 (in determining

whether agency action is “arbitrary” or “capricious”

under Administrative Procedure Act, court must

“review the whole record or those parts of it cited by a

party.”); Universal Camera Corp. v. NLRB, 340 U.S.

474, 488 (1951) (reviewing courts must look at “the

record in its entirety” that was before the agency

before determining that the evidence did not support

the agency’s decision).

A reviewing court acts contrary to law when —- as

the Ninth Circuit did here - it invalidates an agency

action based only on a review of selected facts in the

record, and fails to consider the entire record and all

facts therein supporting the agency’s decision.

D. The Ninth Circuit Failed to Apply the

Required Deference, But Instead

Conducted De Novo Review of Selected

Facts

The Ninth Circuit contravened this Court’s

decisions discussed above. The court went far beyond

its legal mandate to verify whether the record reflected

“a rational connection between the facts found and the

choice made.” See Baltimore Gas, 462 U.S. at 105.

Instead, the court openly substituted its own judgment

for EPA’s well-considered technical determination on

the meaning and weight of windrose data for the

January 19 and 25, 1998 exceedances.

In making the Section 179B Finding, EPA did

not make a snap judgment based only on one type of

data; it followed carefully considered EPA guidance

concerning several types of evidence to be considered

in such analyses. This Section 179B Guidance is itself

the product of substantial agency expertise in

evaluating complex matters of international emissions,

and is entitled to substantial deference by reviewing

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courts under Chevron, U.S.A., Inc. v. NRDC, 467 U.S.

837 (1984).

The Ninth Circuit ignored Chevron by

disregarding EPA’s finding that the Attainment

Demonstration provided substantial supporting data

under three of the five example methods in the Section

179B Guidance. Instead, its sole ground for reversing

the Finding is that it “runs counter to the evidence” of

January 19 and 25 windroses showing mixed northwest,

west and southwesterly wind components.® App. 12a.

The court simply disagreed with EPA’s technical

determination that the mixed winds on those days

evidenced sufficient southerly components to

contribute to cross-border PM-10 _ transport,

determining instead that “EPA’s notion of what

constitutes a southerly wind in the windroses is, at the

least, expansive and, at most, positively incorrect.” Id.

The court concluded, without further discussion, that a

“southerly component’ of the west-southwesterly

variety . . . does not support the theory of transport

6 The only other record evidence even cited by the court is data

proffered by Sierra Club that, on January 19 and 25, “monitors

south of Brawley (and thus closer to the border with Mexico)

recorded significantly lower levels of PM-10 than those recorded at

Brawley.” App. 10a-1la. The court does not state whether it

relied on this data in reversing EPA’s Section 179B Finding. In

any event, the court fails to acknowledge (as EPA did) that not

only was this data outdated, but that other monitoring data south

of Brawley for the same time frame indicated PM-10 levels as high

or higher than those at Brawley, supporting the view that

significant PM-10 was being transported from Mexicali. See ER 62

(1997 Transport Study data relied upon by Sierra Club), App. 76a-

78a (noting that EPA considered 1997 Transport Study, but that

data submitted in State’s Attainment Demonstration was more up-

to-date and reliable).

from Mexico.” App. 13a.

The court then swept away hundreds of pages of

supporting evidence in EPA’s administrative record by

concluding that “there simply is no possibility that

Mexican transport could have caused the observed PM-

10 exceedances on January 19 and 25.” Id. Not

surprisingly, the court’s truncated analysis of a complex

record resulted in error. More importantly, the court

ignored EPA’s reasonable assessment of the entire

body of technical evidence in the record, including

notable areas of data discussed below.

1. The Windrose Data

First, the court ignored the critical factor of

wind “stagnancy” on the January 19 and 25 exceedance

days, and did not apply (as EPA did) the type of

nuanced pollutant transport analysis required

whenever “stagnant” winds are involved. EPA

recognized that characterization of wind speed and

direction becomes highly complex when winds are

“stagnant.” “Stagnant” does not mean that winds are

absent, but that wind speeds average less than 3.2 m/s.

See ER 103-04. In such conditions, wind “drift” is

difficult to measure, and windroses by themselves may

not provide reliable information on PM-10 transport.

See ER 104. When winds are “stagnant,” additional

data are required to reliably predict PM-10 transport.’

ER 103-04.

7 The court also failed to discuss the other windroses in the record,

documenting that winds in Imperial County generally prevail from

the south. See Supp. ER 20, 30, 40, 51, 61, 71, 81, 91, 101. These

windroses show that Mexican PM-10 emissions can drift across the

border and build up in Imperial County over multiple days,

including the days before the January 19 and 25 exceedances.

Unlike the court of appeals, EPA fully

considered the issue of wind “stagnancy” on the

January 19 and 25 exceedance days. App. 53a-56a.

EPA acknowledged that such stagnant winds were, by

definition, “ill defined” and needed to be analyzed in the

context of other information in the record. Jd. Despite

these inherent limitations, EPA recognized that the

available data did indicate some flow from the southern

half of the compass at least 14 of the 24 hours on each

day. Id.

For these reasons, while recognizing the

inherent uncertainty involved with such low speed

winds, EPA reasonably concluded that the windrose

evidence for the January 19 and 25 exceedance days

tended to support the theory that some PM-10

emissions measured in Imperial County on those days

originated from Mexico, and that, taken in context, the

amount of such emissions likely was enough to cause

the slight PM-10 exceedances on those days. Id.

2. Rainfall Data and Receptor Modeling

The court of appeals also failed to consider the

rainfall data in the record for January 1993. In that

month, Imperial County received the highest monthly

rainfall ever recorded (over 3.4 inches). See District’s

Comments at 12-13, 29. Indeed, the heaviest rainstorm

of the year soaked the ground throughout Imperial

County through January 18, 1993 - immediately before

the January 19 and 25 exceedances. See id. at 12-13, 29,

35-48. All of this data was incorporated into the

administrative record. ER 191.

This data indicates that local “dry ground”

sources of PM-10 in Brawley — the source of the vast

majority of locally-generated PM-10 (see ER 88-89) -

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would have been suppressed on January 19 and 25" due

to the soaked ground. However, the soaked ground

would not have suppressed many of the major sources

of PM-10 in Mexicali, including tire-burning, “black

smoke” emissions from Mexicali kilns, smokestack

emissions from uncontrolled industrial sources, and

vehicular combustion of high-sulfur diesel fuel in and

around Mexicali. See Supp. ER at 7-8, 13-15. The

court’s opinion ignores this rainfall evidence — evidence

incorporated into the record and further supporting

EPA’s Finding.

3. Windfield Data

The Opinion also ignores windfield evidence

indicating that winds in and immediately around

Brawley on January 25, 1993 were light and variable

with southwesterly components for a significant part of

the day. ER 125-27. The January 25 windfields show

that winds throughout the day were light and had

predominantly southwesterly and west-southwesterly

components. ER 124-26. EPA correctly interpreted

these windfields as suggesting “stagnant conditions

with winds ill defined,” but providing sufficient

additional evidence of “some southerly flow” of PM-10

emissions from Mexico. App. 54a-56a.

4. Proximity, Magnitude and Density of

Mexicali PM-10 Emissions vs. Slight

Exceedances of NAAQS

Finally, the slight measured exceedances of the

150 ug/m?* standard on January 19 and 25, 1993 (162 and

175 ug/m*) mean that very little influence from Mexican

emissions was required to push otherwise compliant

PM-10 readings over the 24-hour PM-10 NAAQS. As

discussed above, it is undisputed that the magnitude

‘

’ 4

;

and density of PM-10 emissions in adjacent Mexicali are

far higher than in all of Imperial County. App. 29a-30a.

The totality of evidence in the record for all exceedance

days shows a clear pattern of cross-border transport of

these massive PM-10 emissions.

EPA properly relied on this gross disparity in

emissions magnitude and density, and the proximity of

these emissions to the County, as still further evidence

to support the Finding. Jd. The Ninth Circuit

improperly second-guessed that judgment.

E. The Ninth Circuit’s Decision Threatens

Recurring Conflicts on the Scope of

Deference to Expert Agency Findings, an

Issue of National Importance

While the conflict with this Court and the federal

Circuits alone warrants certiorari, the recurring

conflicts the Ninth Circuit’s decision will cause in the

area of judicial deference to agency decisions only

enhance the need for review. This Court has applied

the same deference to other agencies’ expert decisions

where the administrative record contains mixed facts.

See, e.g., Marsh, 490 U.S. at 377 [Army Corps of

Engineers]; Baltimore Gas, 462 U.S. at 105 [Nuclear

Regulatory Comm.]; FPC, 404 U.S. at 463 [Federal

Power Comm.]; see also FCC v. Nat. Citizens Comm.

for Broadcasting, 436 U.S. 775, 814 (1978) (“[C]omplete

factual support in the record for the [FCC’s] judgment

or prediction is not possible or required; ‘a forecast of

the direction in which future public interest lies

necessarily involves deductions based on the expert

knowledge of the agency.”’) (internal citation omitted).

Deference to agency expertise not only underlies

this Court’s decisions on the review of agency

rulemaking, but also forms the backbone of its agency

deference jurisprudence under Chevron. See, ¢€.9.,

Pension Benefit Guaranty Corp. v. LTV Corp., 496 U.S.

633, 651-52 (1990) (“[P]ractical agency expertise is one

of the principal justifications behind Chevron

deference.”) Allowing the decision below to stand

would pose a grave threat to decades of jurisprudence

founded on the basic principle of judicial respect for

agency expertise.

II. THE COURT SHOULD GRANT CERTIORARI

TO CLARIFY THE CIRCUMSTANCES UNDER

WHICH DISCRETIONARY, TECHNICAL

AGENCY DECISIONS MAY BE REMANDED

WITH INSTRUCTIONS FOR THE AGENCY TO

ENTER A NEW SUBSTANTIVE DECISION.

After incurring three summary reversals from

this Court for violating the traditional rule of agency

remand in the immigration context,® the Ninth Circuit

now threatens to spread this error to a new area of

administrative law. As discussed above, the Ninth

Circuit incorrectly concluded that the Finding was

“without substantial basis in fact.” But even if the

court thought the evidence in the record was

inadequate, it was not empowered to remand with

8 See INS v. Chen, 537 U.S. 1016 (2002) (reversing Ninth Circuit

for failing to remand to Board of Immigration Appeals and for

substituting its own factual conclusions for those of Board); INS v.

Ventura, 537 U.S. 12 (2002) (same); INS v. Elias-Zacarias, 502

U.S. 478 (1992) (same); see also Jahed v. INS, 356 F.3d 991, 1002

(9 Cir. 2004) (Kozinski, J, dissenting) (“{O]ur court seems bent on

denying the BIA the deference a reviewing court owes an

administrative agency. Instead, my colleagues prefer to tinker — to

do the job of the Immigration Judge and the BiA, rather than their

own.”)

instructions for EPA to reclassify Imperial County to

“serious” nonattainment. The court was required to

remand the case to EPA for further EPA consideration

consistent with the court’s opinion. Its failure to do so

not only constitutes reversible error, but threatens the

consistent application of this Court’s jurisprudence on

remand.

This Court has held that if a reviewing court

finds:

the record before the agency does not

support the agency action . . . the proper

course, except in rare circumstances, is to

remand to the agency for additional

investigation or explanation. The

reviewing court is not generally

empowered to conduct a de novo inquiry

into the matter being reviewed and to

reach its own conclusions based on such

an inquiry.

Florida Power & Light Co. v. Lorion, 470 U.S. 729, 744

(1985); see also LTV Corp., 496 U.S. at 654 (remand “is

the preferred course” if record deemed inadequate to

support decision); Camp v. Pitts, 411 U.S. 188, 141-42

(1973) (if record failed to explain agency action

sufficiently, remedy is not to hold de novo hearing but

to remand to obtain from the agency additional

explanation.) This rule flows from _ traditional

considerations of according respect to the agency as the

fact finder and sole entity authorized by statute to

make the substantive policy decision involved. See

Chenery, 318 U.S. at 88 (“a judicial judgment cannot be

made to do service for an administrative judgment ...

an appellate court cannot intrude upon the domain

which Congress has exclusively entrusted to an

administrative agency.”)”

Less than two years ago, in INS v. Ventura, 537

U.S. 12, 17-18 (2002), this Court summarily reversed

the Ninth Circuit in similar circumstances when it

failed to remand an asylum matter to the Board of

Immigration Appeals, but instead decided the case de

novo in the asylum applicant’s favor based on its own

substantive evaluation of the evidence. The Court

stressed the importance of remanding for further

agency proceedings

a matter that statutes place primarily in

agency hands... The agency can bring its

expertise to bear on the matter; it can

evaluate the evidence; it can make an

initial determination; and, in doing so, it

can, through informed discussion and

analysis, help a court later determine

whether its decision exceeds the leeway

that the law provides.

Ventura, 537 U.S. at 16-17. The Ninth Circuit’s

conclusion that the evidence “compelled” its finding for

the applicant was legally inadequate because the record

° Other federal circuits have echoed this long-held requirement to

remand agency actions deemed lacking in evidentiary support.

See, e.g., County of Los Angeles v. Shalala, 192 F.3d 1005, 1011-12

(D.C. Cir. 1999), cert. denied, 530 U.S. 1204 (2000); Seavey v.

Barnhart, 276 F.3d 1, 12 (1* Cir. 2001); Ward v. Brown, 22 F.3d

516, 522-23 (2d Cir. 1994); Dia v. Ashcroft, 353 F.3d 228, 260 (3d

Cir. 2003); West Virginia Highlands Conservancy, Inc. v. Norton,

343 F.3d 239, 248-49 (4 Cir. 2003); Kroger Co. v. Regional Atrport

Auth. of Louisville and Jefferson County, 286 F.3d 382, 387 (6"

Cir. 2002); Mickeviciute v. INS, 327 F.3d 1159, 1164-65 (10 Cir.

2003).

was “at most, ambiguous about the [factual] matter” at

issue, and because remand would allow further

development of the record by the agency. Id. at 17-18.

The decision below repeats the Ninth Circuit’s

error in Ventura. The remand with instructions here

dictates, by judicial fiat, a substantive outcome on a

policy decision entrusted solely to EPA’s expertise.

The substantial amount of evidence in the record, apart

from just the windroses, makes the record “at most,

ambiguous” about whether the January 19 and 25

exceedances would not have occurred but for Mexican

emissions. That ambiguity may be resolved only by

remand and further development of the record by EPA.

The cases cited by the Ninth Circuit do not

support remand with instructions here. See Alvarado

Cmty. Hosp. v. Shalala, 155 F.3d 1115, 1125 (9 Cir.

1998), as amended, 166 F.3d 950 (9 Cir. 1999)

(remanding with instructions to consider new data, not

dictating a substantive result); Smolen v. Chater, 80

F.3d 1273, 1292 (9*" Cir. 1996) (in cases concerning social

security benefits, court has discretion to remand, or to

award benefits if the record is fully developed and

further proceedings would serve no useful purpose);

Sierra Club v. EPA, 311 F.3d 853 (7 Cir. 2002)

(remanding with instructions where EPA lacked

authority to grant attainment date extension, without

any dispute over record evidence or discussion of the

remand issue itself).

Not one of these cases involves any “rare

circumstance” approximating the facts of this case.

Indeed, the only “rare circumstance” cited by the court

as justifying remand with instructions is the court’s de

novo factual finding on the windrose data and its

assertion that “the record here has been fully

-developed, and the conclusions that must follow from it

are clear.” App. 13a-14a. But as discussed above, the

totality of record evidence - beyond windroses alone —

more than adequately supports EPA’s expert decision

that Mexican PM-10 emissions provided at least that

small amount of influence necessary to cause the slight

exceedances observed.

Thus, the court rationale for remanding with

instructions is mistaken about the standard and the

evidence. There is no “rare circumstance” justifying

remand with instructions here. This Court should

grant certiorari to clarify quickly and decisively that a

reviewing court cannot make its own de novo decisions

about the meaning of technical evidence within an

agency’s expertise, then parlay that improper de novo

decision into a “rare circumstance” justifying remand

with instructions for the agency to reach a substantive

policy decision otherwise entrusted to its discretion.

CONCLUSION

For the reasons above, the petition for a writ of

certiorari should be granted.

Respectfully submitted

R. RAYMOND ROTHMAN

Counsel of Record

MICHAEL S. MCDONOUGH

BINGHAM MCCUTCHEN LLP

355 South Grand Avenue

Suite 4400

Los Angeles, CA 90071

(213) 680-6400

Attorneys for Petitioner

(Any footnotes trail end of each document)

No. 01-71902

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

SIERRA CLUB,

Petitioner,

IMPERIAL COUNTY AIR

POLLUTION CONTROL DISTRICT,

Intervenor,

UNITED STATES ENVIRONMENTAL

PROTECTION AGENCY; MICHAEL O. LEAVITT,

Respondents.

October 9, 2003, Resubmitted

October 9, 2003, Filed

COUNSEL: David S. Baron, Earthjustice Legal

Defense Fund, Washington, D.C., argued the cause for

petitioner Sierra Club and submitted briefs.

Thomas H. Pacheco, United States Department of

Justice, San Francisco, California, argued the cause for

respondent Environmental Protection Agency and

submitted briefs. Thomas L. Sansonetti, Assistant

Attorney General, Jan Taradash, Associate Regional

Counsel, Environmental Protection Agency, and

Geoffrey Wilcox also were on the briefs.

Rick R. Rothman, McCutheon, Doyle, Brown &

Enersen, LLP, Los Angeles, California, argued the

cause for intervenor Imperial County Air Pollution

Control District and submitted briefs. William H.

Freedman and Michael S. McDonough also were on the

briefs.

Michael S. Rhodes, Colley Godward LLP, San Diego,

California, filed a brief on behalf of amicus curiae

American Lung Association of San Diego and Imperial

Counties. Andrea S. Hoffman, Robert R. Veith, and

Craig A. Guthery also were on the brief.

JUDGES: Before: William C. Canby, Jr., Diarmuid F.

O’Scannlain, and William A. Fletcher, Circuit Judges.

Opinion by Judge O’Scannlain.

OPINIONBY: Diarmuid F. O’Scannlain

OPINION: AMENDED OPINION

O’SCANNLAIN, Circuit Judge:

We must decide whether the U.S. Environmental

Protection Agency lawfully concluded that a Southern

California county would have achieved the 24-hour air

quality standards required by the Clean Air Act but for

the negative effects of transborder emissions from

Mexico.

Imperial County encompasses approximately 4,600

square miles in Southeastern California and is bordered

by Riverside County to the north, Mexico to the south,

Arizona to the east, and San Diego County to the west.

The county shares approximately 80 miles of border

with Mexico. Calexico, one of three significant

population centers in the county, sits close by the

border, not far from the Mexican city of Mexicali.

Moving north from the border, the county’s other two

major population centers are El Centro and Brawley.

As of 1999, the county had approximately 142,000

inhabitants.

The Imperial Valley runs roughly through the center of

the county, from the northwest to the southeast, and

across its southern border into Mexico. Most of

Imperial County, save for a small stretch of land on the

county’s eastern end, falls within the Imperial Valley

Planning Area (“Imperial Valley”), and Intervenor

Imperial County Air Pollution Control District nl

serves as the local governmental agency charged with

administering and enforcing the requirements of the

Clean Air Act and other federal, state and local air

quality laws and regulations.

In 1987, pursuant to the Clean Air Act, 42 U.S.C. 88

7401-7671q (“CAA” or “Act”), the U.S. Environmental

Protection Agency (“EPA”) adopted new national

ambient air quality standards (“NAAQS”) based on

health studies demonstrating the harmful health effects

of particulate matter. n2 See 42 U.S.C. § 7409. To

comply with such standards, — the expected

concentration of PM-10 in a given area of the country

cannot exceed (1) 150 [mu]g/m3 for more than one day

per calendar year (the “24-hour standard”) or (2) an

expected annual arithmetic mean of 50 [mu]g/m3 (the

“annual standard”). 40 C.F.R. §§ 50.6(a) and (b). The

States are responsible for ensuring compliance with

both standards for PM-10 and must formulate a state

implementation plan (“SIP”) for doing so. See 42 U.S.C.

§§ 7407(a) and 7410(a).

In 1990, Congress once again amended the Act to

classify areas of the country as “attainment” or

“nonattainment,” the former classification comprising

those areas that had met the NAAQS for PM-10, the

latter those that had not. 42 U.S.C. § 7407(d). n3 The

amendments provided for a further level of

classification among those areas designated as

nonattainment as either “moderate” or “serious.” Id. §

7518.

Imperial Valley was classified as a moderate PM-10

nonattainment area. n4 The Act required such

“moderate” areas to meet the NAAQS by December 31,

1994 (the “attainment date”). id. § 7513(c)(1). Moderate

areas failing to comply with the NAAQS, by the terms

of the Act, would be reclassified as “serious,” id. §

7513(b)(2), and assigned a later attainment date,

December 31, 2001, but would be required to adopt

more stringent pollution controls. Jd. §§ 7513(c)(2) &

7518a(b).

The 1990 Amendments also included a provision, CAA §

179B, which spared from § 7513(b)(2) reclassification

“any State that establishes to the satisfaction of the

Administrator that, with respect to a PM-10

nonattainment area in such State, such State would

have attained the national ambient air quality standard

for carbon monoxide nd by the applicable attainment

date, but for emissions emanating from outside the

United States.” 42 U.S.C. § 7509a(d). EPA issued

administrative guidance in 1994 setting forth “several

types of information [that] may be used to evaluate the

impact of emissions emanating f:om outside the U.S.”

and demonstrate that a border area’s failure to meet

the NAAQS was due to such foreign emissions. State

Implementation Plans for Serious PM-10

Nonattainment Areas, and Attainment Date Waivers

for PM-10 Nonattainment Areas Generally; Addendum

to the General Preamble for the Implementation of

Title I of the Clean Air Act Amendments of 1990, 59

Fed. Reg. 41,998 (Proposed Aug. 16, 1994) (“General

Preamble guidance” or “guidance”).

The five examples suggested by the EPA’s General

Preamble guidance are:1. The use of PM-10 monitors

and meteorological information near the border to

“evaluate and quantify any changes in monitored PM-10

concentrations with a change in the predominant wind

direction.” 59 Fed. Reg. at 42,001.

2. The compilation of a comprehensive inventory of PM-

10 emissions “within the U.S. in the vicinity of the

nonattainment area . . . [to] demonstrate that the

impact of those sources on the nonattainment area after

application of reasonably available controls does not

cause the NAAQS to be exceeded.” Jd.

3. Analysis of “ambient sample filters for specific types

of particles emanating from across the border (although

not required, characteristics of foreign sources may be

helpful).” Jd.

4. A comparison between inventories of emission

sources on both sides of the border and the relative

magnitude of each. Id.

5. The use of “air dispersion and/or receptor modeling

to quantify the relative impacts on the nonattainment

area of sources located within the U.S. and of foreign

sources of PM-10 (this approach combines information

collected from the international emission inventory,

meteorological stations, ambient monitoring network,

and analysis of filters).” Jd.EPA prefaced these

examples by noting that “the State may use one or

more of these types of information or other techniques,

depending on their feasibility and applicability, to

evaluate the impact of emissions emanating from

outside the U.S. on the nonattainment area.” Jd. EPA

added that it “will consider the information presented

by the state for individual attainment areas on a case-

by-case basis in determining whether an area may

qualify for treatment under section 179B.” Id.

Imperial Valley’s attainment date -- December 31, 1994

-- came and went, but EPA took no action regarding

reclassification. Almost six years later, when EPA still

had not taken any action, the Sierra Club filed suit in

U.S. District Court for the District of Columbia to

compel EPA to make a reclassification determination

regarding Imperial Valley. The suit was resolved by

consent decree, under the terms of which EPA agreed

to make a reclassification determination for Imperial

Valley by October 9, 2001.

On August 10, 2001, EPA issued a notice of proposed

rule-making (“NPR”) in which it proposed “to find that

the State of California has established to EPA’s

satisfaction that the Imperial Valley Planning Area

(Imperial County) . . . would have attained the national

ambient air quality standards (NAAQS) for particulate

matter ... by the applicable . . . attainment date, but for

emissions emanating from outside the United States,

i.e., Mexico.” Clean Air Act Finding of Attainment and

Alternative Finding of Nonattainment and

Reclassification to Serious; California-Imperial Valley

Planning Area; Particulate Matter of 10 microns or less

(PM-10), 66 Fed. Reg. 42,187 (proposed August 10,

2001). né6 The EPA action was based on the “Imperial

County PM-10 Attainment Demonstration,” a

document filed on July 18, 2001 and developed by the

State which used data culled from six PM-10 monitors

in the county, spatial plots, n7 windroses, né back

trajectories, n9 and a model based upon an inventory of

emissions sources in the Imperial Valley. Based upon

this information, the State contended that but for

emissions from Mexico which were borne aloft and

across the border by the wind, the county would have

met both the annual and 24-hour standards by the

attainment date.

Sierra Club submitted comments opposing the

proposed rule, arguing that the State had failed to

make the required demonstration. Specifically, Sierra

Club contended that (1) under the Act, the State was

required to use a certain kind of modeling in order to

make the required demonstration; (2) the emissions

inventory used by the State in its model was neither

current nor accurate; (3) the State had failed to show

that emissions from Mexico have actually caused

violations to occur at U.S. monitors, but instead had

merely assumed such causation; and (4) the State had

failed to account for exceedances of the NAAQS after

the December 31, 1994 attainment date, let alone show

that those exceedances were the result of emissions

from Mexico. nl0

Rejecting Sierra Club’s challenge to the State’s

demonstration, EPA issued a final rule on October 19,

2001, finding that “the State of California has

established to EPA’s satisfaction that the Imperial

Valley Planning Area (Imperial County) . . . would have

attained the national ambient air quality standards for

[PM-10]... by the applicable Clean Air Act attainment

date, December 31, 1994, but for emissions emanating

from outside the United States, i.e., Mexico.” Clean Air

Act Finding of Attainment; California-Imperial Valley

Planning Area; Particulate Matter of 10 Microns or

Less (PM-10), 66 Fed. Reg. 53,106 (adopted October 19,

2001). EPA found that the State demonstration

“provides the best qualitative analysis of the emissions

from Mexico possible for the Imperial County area for

the period in question.” Id. at 53,109. EPA concluded

thatwhile Sierra Club raises some important issues,

EPA was aware of those issues prior to the proposed

rulemaking and has not been convinced by Sierra Club

that the State’s 179B(d) demonstration is inadequate

and that the finding of nonattainment and

reclassification to serious should be finalized.Id. at

53,107.

Sierra Club timely petitions this court for review of the

EPA Administrator’s decision.

“Review of agency action to determine its conformity

with ...the CAA... is governed by the judicial review

provisions of the [Administrative Procedure] Act,

((““APA”)] 5 U.S.C. §§ 701-706.” Pub. Citizen v. Dep’t of

Transp., 316 F.3d 1002, 1021 (9th Cir. 2003). Under §

706 of the APA, the court must satisfy itself that the

agency action was not “arbitrary, capricious, an abuse

of discretion, or otherwise not in accordance with law.”

5 U.S.C. § 706(2)(A). We have interpreted this

statutory provision as requiring the agency to

“articulate[ ] a rational connection between the facts

found and the choice made.” Arizona Cattle Growers’

Ass’n v. U.S. Fish & Wildlife Serv., 273 F.3d 1229, 1236

(9th Cir. 2001).

We recognize that where, as here, a court reviews an

agency action “involving primarily issues of fact,” and

where “analysis of the relevant documents requires a

high level of technical expertise,” we must “defer to the

informed discretion of the responsible federal

agencies.” Marsh v. Oregon Natural Res. Council, 490

U.S. 360, 377, 104 L. Ed. 2d 377, 109 S. Ct. 1851 (1989);

see also Baltimore Gas & Elec. Co. v. Natural Res. Def.

Council, Inc., 462 U.S. 87, 108, 76 L. Ed. 2d 487, 103 S.

Ct. 2246 (1983) (“When examining this kind of scientific

determination ... a reviewing court must generally be

at its most deferential.”); Arizona Cattle Growers’

Ass’n, 273 F.3d 1229, 1236 (9th Cir. 2001) (“We are

deferential to the agency’s expertise in situations, like

that here, where resolution of the dispute involves

primarily issues of fact.”). While our deference to the

agency is significant, we may not defer to an agency

decision that “is without substantial basis in fact.” Fed.

Power Comm’n v. Florida Power & Light Co., 404 U.S.

458, 463, 30 L. Ed. 2d 600, 92 S. Ct. 637 (1972). Indeed,

the Supreme Court has made clear that, in considering

an agency’s explanation for its action, courts “must

consider whether the decision was based on a

consideration of the relevant factors and whether there

has been a clear error of judgment.” Motor Vehicle

Mfrs. Ass’n of U.S. v. State Farm Mut. Auto Ins. Co.,

10a

463 U.S. 29, 43, 77 L. Ed. 2d 4438 (1983) (internal

quotation marks omitted). One example provided by

the Court of such a “clear error of judgment” sufficient

to constitute arbitrary and capricious agency action is

when “the agency offer{[s] an explanation that runs

counter to the evidence before the agency, or is so

implausible that it could not be ascribed to a difference

in view or the product of agency expertise.” Id.

At oral argument, we questioned counsel for EPA

about two specific dates, January 19 and January 25,

1993, on which exceedances of the 24-hour PM-10

standard were recorded at Brawley, twenty-one miles

north of the County’s border with Mexico. Examining

the evidence produced by the State, EPA agreed with

the State’s assertion that these exceedances likely were

caused by wind-borne PM-10 from Mexico. Sierra Club

challenged this conclusion -- both in its briefs before

this court and at oral argument -- by noting that the

wind data on those two days do not comport with the

theory of cross-border transport of PM-10. Specifically,

on January 19 and January 25, 1993, the winds in

Imperial County show significant -- even predominately

-- westerly components. That is, the winds were largely

out of the west. Given that Brawley is, obviously, north

of the Mexican border -- and northwest of Mexicali, the

Mexican city alleged to be the principal source of

transborder PM-10 -- Sierra Club argues that it is

highly unlikely that such exceedances could be

attributed to emissions from Mexico. Sierra Club

buttresses its assertion that emissions from Mexico

could not have caused the two exceedances at Brawley

by noting that, on the two days in question, monitors

south of Brawley (and thus closer to the border with

Mexico) recorded significantly lower levels of PM-10

lla

than those recorded at Brawley. Presumably, if wind-

borne emissions traveling northward from Mexico were

the cause of the exceedances at Brawley, one could

expect similarly high levels of PM-10 closer to the

border. The record indicates that such was not the case.

There was some uncertainty at oral argument -- neither

the parties nor the record provided an answer -- as to

whether either or both exceedance days were

sufficient, standing alone, to constitute a violation of the

24-hour PM-10 NAAQS. To put it another way, the

question is: If the wind-borne emissions from Mexico

did not cause either or both of such exceedances, must

the panel grant the petition and vacate EPA’s finding?

We ordered supplemental briefing on the matter. The

parties’ supplemental briefs informed us that the

Brawley monitor sampled the air quality only on every

sixth day. In order to determine whether the two

recorded exceedances constituted a violation of the 24-

hour NAAQS for PM-10, which allow only for one

exceedance per year of the 24-hour standard in a given

area, the actual number of exceedances is adjusted to

take account of the days that are not sampled. The

adjustment is made according to a formula set forth at

40 C.F.R. Part 50, Appendix K. Applying this formula

to the two recorded exceedances at Brawley reveals

that the expected number of exceedances of the 24-hour

standard is 4.3 days per year, far above the one day

exceedance allowed under the NAAQS. Applying the

formula to only one of the two days in question results

in exceedance of the 24-hour standard on 2.14 days per

year. Thus, both parties agreed in their supplemental

briefs that either one of the two recorded \exceedances

would have been enough to trigger a violation of the 24-

12a

hour PM-10 NAAQS. EPA continued to assert,

however, that the cause of both exceedances was

emissions from Mexico and thus, Imperial Valley would

have attained the 24-hour standard but for such

emissions.

We disagree. The pattern of recorded PM-10 levels on

January 19 and January 25, 1993, does not comport with

the State’s theory that emissions from Mexico -- and

Mexicali in particular -- caused the Brawley monitors to

exceed the 24-hour NAAQS for PM-10. We believe that

EPA’s conclusion that Imperial Valley would have

satisfied the 24-hour standard but for emissions from

Mexico “runs counter to the evidence” before the

agency concerning the exceedances at Brawley. State

Farm, 463 U.S. at 43. As noted above, the data upon

which EPA relies show winds trending, at best, in a

southwesterly direction, but even then only nominally

so. The windroses, meanwhile, show a similar west to

southwesterly component. The evidence most

supportive of EPA’s position is the windrose from

Calipatria, 10.5 miles north of Brawley, which reveals

very slight south-southeasterly winds. But that same

windrose shows stronger winds from the northwest. At

oral argument, counsel for EPA had no explanation for

the decided lack of southerly winds on the days in

question, but nevertheless insisted that the data

showed winds with a southerly component. There are

two problems with counsel’s assertion, which was

reiterated in EPA’s supplemental brief. First, EPA’s

notion of what constitutes a southerly wind in the

windroses is, at the least, expansive and, at most,

positively incorrect. Second, the “southerly component”

EPA professes to locate in the wind data would appear

to be inconsistent with its theory of the case: that is,

13a

whatever “southerly component” the wind data reveals

is of the west-southwesterly variety and thus does not

support the theory of transport from Mexico.

Ill

Although the normal course of action when the record

fails to support an agency’s decision “is to remand to

the agency for additional investigation or explanation,”

Florida Power & Light Co. v. Lorion, 470 U.S. 729, 744,

84 L. Ed. 2d 648, 105 S. Ct. 1598 (1985), both Supreme

Court and Ninth Circuit precedent acknowledge the

propriety of remanding with instructions in exceptional

cases. See, e.g., id. (“except in rare circumstances”);

Alvarado Cmty. Hosp. v. Shalala, 155 F.3d 1115, 1125

(9th Cir. 1998) as amended by 166 F.3d 950 (9th Cir.

1999) (remanding with instructions to recalculate

Medicare service provider reimbursements using

newly-available data); Smolen v. Chater, 80 F.3d 1273,

1292 (9th Cir. 1996) (remanding with instructions to

award Social Security benefits because “the record has

been fully developed and . . . further administrative

proceedings would serve no useful purpose”); see also

Sierra Club v. EPA, 311 F.3d 853 (7th Cir. 2002)

(remanding with instructions where the EPA had

exceeded its statutory authority by granting a

nonattainment exception on statutorily-unenumerated

grounds).

We think this is such a case. Based on the data and the

reports in the record, there simply is no possibility that

Mexican transport could have caused the observed PM-

10 exceedences on January 19 and January 25. We fail

to see how further administrative proceedings would

serve a useful purpose; the record here has been fully

l4a

developed, and the conclusions that must follow from it

are clear. We therefore GRANT the petition, VACATE

the order, and REMAND WITH INSTRUCTIONS

that the EPA classify Imperial Valley as a “serious”

nonattainment area. nll

Footnotes

nl The parties refer to Intervenor as “the State.” We

adopt their practice.

n2 Particulate matter, for the purposes of the NAAQS,

is defined as airborne material having an aerodynamic

diameter of 10 microns or less. Hence the common |

abbreviation “PM-10.” Studies showed that, when |

inhaled, PM-10 particles can penetrate deep into the |

respiratory tract where they can lodge in the lung

tissue and lead to a variety of respiratory problems.

n3 There is an additional category, “unclassifiable,” for

those areas where there is insufficient information upon

which to base a classification.

n4 The sources of PM-10 in Imperial County are dust

(“primary geological material,” contributing more than

70 percent of the concentration), motor vehicle

emissions (10 to 15 percent), and agricultural burning (4

to 8 percent).

nd All parties agree that the use of the term “carbon

monoxide” instead of “PM-10” is simply an editorial

mistake. See Petitioner’s Opening Br. at 7 n.2;

Response Br. at 6 n.5; and Intervenor’s Br. at 7 n.4.

n6 As the title of the proposed rule indicates, if it were

convinced by the public comments, EPA would

15a

conclude that the State failed to make a sufficient

showing under § 179B. The NPR was accompanied by a

technical support document (“TSD”) that examined the

evidence put forward by Imperial Valley in support of

its assertion that it would have attained the NAAQS

but for emissions from Mexico.

n7 Spatial plots demonstrate the concentration of PM-

10 measurements at various monitoring stations in a

given area. In this case, the State contends that spatial

plots tend to show a high concentration of PM-10 at

those stations close to the border, with decreasing

levels the further one moves north, consistent with its

theory that windblown emissions from Mexico waft into

Imperial County, causing exceedances of PM-10

NAAQS.

n8 A windrose is a diagram showing the percentage of

time that wind blows from each compass direction for

various ranges of wind speeds.

n9 A back trajectory is a map that, by measuring the

speed and direction of winds a certain distance above

the ground, attempts to show where a given parcel of

air that hits a ™onitor most likely originated. According

to the Stats Attainment Demonstration, “the

trajectories demonstrate 1) when the air passes

through Mexico and then into Imperial County; 2) when

the air might have circumvented the monitors in

Calexico and impacted the northern monitors in

Imperial County; and 3) when air may have come from

Mexico, but not necessarily through Mexicali.”

nl0 Sierra Club also contended that the refusal to

reclassify Imperial Valley as a serious nonattainment

RI SE Tee

16a

area would be unlawful because the State had failed to

submit a state implementation plan. This claim is not

raised in its petition for review.

nll Beceuse we have reversed EPA’s conclusion with

respect to the 24-hour NAAQS, and because the Ninth

Circuit has previously held that an area must meet both

the 24-hour and annual NAAQS in order to comply with

Clean Air Act requirements, see Ober v. EPA, 84 F.3d

304, 309 (9th Cir. 1996), we need not reach the merits of

Sierra Club’s challenge to EPA’s conclusion regarding

Imperial Valley’s attainment of the annual PM-10

NAAQS.

17a

No. 01-71902

UNITED STATES COURT OF APPEALS

FOR THE NINTH CIRCUIT

SIERRA CLUB,

Petitioner,

IMPERIAL COUNTY AIR

POLLUTION CONTROL DISTRICT,

Intervenor,

UNITED STATES ENVIRONMENTAL

PROTECTION AGENCY; MICHAEL O. LEAVITT,

Respondents.

December 18, 2003, Filed

COUNSEL: For Sierra Club, Petitioner: David S.

Baron, Esq., EARTHJUSTICE LEGAL DEFENSE

FUND, Washington, DC.

For Imperial County Air Pollution Control District,

Intervenor: Rick R. Rothman, Esq., MecCUTCHEN,

DOYLE, BROWN & ENERSEN, LLP, Los Angeles,

CA. William H. Freedman, Esq.. MCCUTCHEN,

DOYLE, BROWN & ENERSEN, LLP, Los Angeles,

CA.

For United States Environmental Protection Agency,

Christine Whitman, Respondents: Administrator,

Environmental Protection Agency, Washington, DC.

General Counsel, ENVIRONMENTAL

18a

PROTECTION AGENCY, Office of the General

Counsel, Washington, DC. Chief Counsel - EPA, U.S.

ENVIRONEMNTAL PROTECTION AGENCY,

Washington, DC. Regional Counsel,

ENVIRONMENTAL PROTECTION AGENCY,

Region 9, San Francisco, CA. Thomas H. Pacheco, Esq,,

UNITED STATES DEPARTMENT OF JUSTICE,

San Francisco, CA.

JUDGES: Before: William C. Canby, Jr., Diarmuid F’.

O’Scannlain, and William A. Fletcher, Circuit Judges.

OPINION: ORDER

The opinion filed October 9, 2003 is hereby amended as

follows: Slip. Op. at 15008, lines 10-8 from the bottom:

Replace the sentence that currently reads “The best

evidence adduced by EPA is the windrose from

Calipatria, several miles south of Brawley, which

reveals very slight south-southeasterly winds” with the

following:

“The evidence most supportive of EPA’s position is the

windrose from Calipatria, 10.5 miles north of Brawley,

which reveals very slight south-southeasterly winds.”

With this amendment, the petition for rehearing is

hereby DENIED.

Intervenor Imperial County Air Pollution Control

District’s motion to stay the mandate is GRANTED

until March 17, 2004 to permit said Intervenor to file a

petition for certiorari with the United States Supreme

Court. If before that date a petition for certiorari is

19a

filed, this stay shall remain in effect until final

disposition by the Supreme Court.

20a

[Federal Register: August 10, 2001

(Volume 66, Number 155, Pages 42187-42193)]

ENVIRONMENTAL PROTECTION AGENCY

40 CFR PART 81

[CA038-FOA; FRL -7031-9]

Clean Air Act Finding of Attainment and Alternative

Finding of Nonattainment and Reclassification to

Serious; California-Imperial Valley Planning Area;

Particulate Matter of 10 microns or less (PM-10)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Proposed rule.

SUMMARY: EPA is proposing to find that the State of

California has established to EPA’s satisfaction that the

Imperial Valley Planning Area (Imperial County), a

PM-10 moderate nonattainment area, would have

attained the national ambient air quality standards

(NAAQS) for particulate matter of ten microns or less

(PM-10) by the applicable Clean Air Act (CAA or the

Act) attainment date, December 31, 1994, but for

emissions emanating from outside the United States,

i.e., Mexico. If EPA takes final action on this proposed

finding, Imperial County will not be subject to a finding

of failure to attain and reclassification to serious.

Alternatively, EPA is proposing to find that Imperial

County did not attain the PM-10 NAAQS by its CAA

mandated attainment date. This proposed finding is

based on monitored air quality data for the PM-10

2la

NAAQS during the years 1992-1994. If EPA takes final

action on this proposed finding, Imperial County will be

reclassified by operation of law as a_ serious

nonattainment area under section 188(b)(2)(A) of the

CAA.

EPA is proposing the above actions in the alternative in

the event that public comments convince EPA that the

State has not established that Imperial County would

have attained the PM-10 NAAQS but for international

transport by the applicable attainment date.

DATES: Comments on this proposed rule must be

received in writing by September 10, 2001.

ADDRESSES: Comments should be addressed to

Doris Lo, U.S. Environmental Protection Agency,

Region 9, Air Division, Planning Office (AIR-2), 75

Hawthorne Street, San Francisco, California 94105.

FOR FURTHER INFORMATION CONTACT: Doris

Lo, U.S. Environmental Protection Agency, Region 9,

Air Division, Planning Office (AIR-2), 75 Hawthorne

Street, San Francisco, California 94105, (415) 744-1287,

lo.doris@epa.gov.

SUPPLEMENTARY INFORMATION:

I. Background

A. CAA Provisions and EPA Actions Concerning

Designation and Classification

On November 15, 1990, the date of enactment of the

1990 Clean Air Act Amendments, PM-10 areas meeting

22a

the qualifications of section 107(d)(4)(B) of the Act were

designated nonattainment by operation of law. Once an

area is designated nonattainment, section 188 of the Act

outlines the process for classification of the area and

establishes the area’s attainment date. Pursuant to

section 188(a), all PM-10 nonattainment areas were

initially classified as moderate by operation of law upon

designation as nonattainment. These nonattainment

designations and moderate area classifications were

codified in 40 CFR part 81 in a Federal Register notice

published on November 6, 1991 (56 FR 56694). The

Imperial Valley Planning Area, consisting of all but the

easternmost portion of Imperial County, was

designated nonattainment and classified as moderate.

See 40 CFR 81.305.

States containing areas which were designated as

moderate nonattainment by operation of law under

section 107(d)(4)(B) were to develop and submit state

implementation plans (SIPs) to provide for the

attainment of the PM-10 NAAQS. Pursuant to section

189(a)(2), those SIP revisions were to be submitted to

EPA by November 15, 1991.

B. CAA Provisions Concerning Reclassification to

Serious Nonattainment

Pursuant to sections 179(c) and 188(b)(2) of the Act,

EPA has the responsibility to determine within 6

months of the applicable attainment date, whether PM-

10 nonattainment areas have attained the NAAQS.

Section 179(c)(1) of the Act provides that these

determinations are to be based upon an area’s “air

quality as of the attainment date,” and section 188(b)(2)

is consistent with this provision. EPA makes the

23a

determinations of whether an area’s air quality is

meeting the PM-10 NAAQS based upon air quality data

gathered at monitoring sites in the nonattainment area.

These data are reviewed to determine the area’s air

quality status in accordance with EPA guidance at 40

CFR part 50, appendix K.

Pursuant to appendix K, attainment of the annual PM-

10 standard is achieved when the annual arithmetic

mean PM-10 concentration is equal to or less than 50

g/m3. Attainment of the 24-hour standard is

determined by calculating the expected number of

exceedances of the 150 g/m8 limit per year. The 24-hour

standard is attained when the expected number of

exceedances is 1.0 or less. A total of 3 consecutive years

of clean air quality data is generally necessary to show

attainment of the 24-hour and annual standards for PM-

10. A complete year of air quality data, as referred to in

40 CFR part 50, appendix K, is comprised of all 4

calendar quarters with each quarter containing data

from at least 75 percent of the scheduled sampling days.

Under section 188(b)(2)(A), a moderate PM-10

nonattainment area must be reclassified as serious by

operation of law after the statutory attainment date if

the Administrator finds that the area has failed to

attain the NAAQS. Pursuant to section 188(b)(2)(B) of

the Act, EPA must publish a notice in the Federal

standard and the resulting reclassifications.

24a

C. CAA Provisions Concerning International Border

Areas

Imperial County shares its southern border with

Mexico. CAA _ section 179B(d) provides that,

notwithstanding any other provision of law, any State

that establishes to the satisfaction of EPA that a PM-10

nonattainment area in such State would have attained

the PM-10 NAAQS by the applicable attainment date

but for emissions emanating from outside the United

States (U.S.) shall not be subject to the provisions of

CAA section 182(b).

Section 179B(a) sets forth the state implementation

plan (SIP) requirements for moderate PM-10 areas that

can make the above demonstration.

II. Proposed Finding of Attainment Under CAA

Section 179B(d)

EPA is today proposing to find that, pursuant to CAA

section 179B(d), the State of California has established

to EPA’s satisfaction that Imperial County attained the

NAAQS for PM-10 by the applicable attainment date,

December 31, 1994, but for emissions emanating from

outside the U.S., and thus shall not be subject to a

finding of failure to attain and reclassification under

CAA section 188(b)(2). As discussed below, this

proposed finding is based on the “Imperial County PM-

10 Attainment Demonstration” (hereafter referred to

as the “179B(d) demonstration”) which was developed

by the Imperial County Air Pollution Control District

(ICAPCD) and transmitted to EPA by the California

Air Resources Board (CARB) on July 18, 2001. July 18,

2001 letter with enclosure from Michael P. Kenny,

25a

Executive Officer, Air Resources Board to Ms. Laura

Yoshii, Acting Regional Administrator, EPA Region

9).fn1

EPA has issued preliminary guidance relating to

serious PM-10 nonattainment areas fn2 (General

Preamble guidance) that includes a discussion of the

requirements applicable to international border areas.

For these areas, the General Preamble guidance

discusses the information and methods that can be used

in determining whether an area qualifies for treatment

under CAA section 179B and then discusses SIP

requirements for areas which are able to demonstrate

that they would be in attainment but for the emissions

emanating from outside the U.S. This proposal does not

address the SIP requirements for the County but only

the question of whether or not the State has established

that Imperial County attained the NAAQS by

December 31, 1994 but for international transport. If

EPA issues a final finding that the nonattainment area

would have attained but for international transport,

EPA will in separate actions address the applicable SIP

provisions and submissions by the State.

The General Preamble guidance states tliat “[s]everal

types of information may be used to evaluate the

impact of emissions emanating from outside the US.

The EPA will consider the information presented by

the State for individual nonattainment areas on a case-

by-case basis in determining whether an area may

qualify for treatment under section 179B. * * ** Tee

General Preamble guidance also suggests five methods

which may be used in determining the impact of

emissions emanating from outside the U.S. and states

that “the State may use one or more of these types of

26a

information or other techniques, depending on their

feasibility and applicability, to evaluate the impact of

emissions emanating from outside the U.S. on the

nonattainment area.” Below is a discussion of each of

the methods as addressed in the 179B(d)

demonstration.

Method 1. Place several ambient PM-10 monitors and a

meteorological station measuring wind speed and

direction in the U.S. non-attainment area near the

international border. Evaluate and quantify any

changes in monitored PM-10 concentrations with a

change in direction in the predominant wind direction.

There are six PM-10 monitors in the nonattainment

area, with two monitors in the proximity of the border

(Calexico-Grant St. and Calexico-Ethel St., each 1.2 km

from the Mexican border). A meteorological station at

the Imperial County Airport was used to provide a

windrose for each exceedance day. The 179B(d)

demonstration provided, for each exceedance day, an

analysis of the transport of PM-10 from Mexico, based

on the spatial distribution of PM-10 throughout the

basin, along with a windrose, and a series of back

trajectories (based on the National Oceanic and

Atmospheric Administration HYSPLIT program).

More details of this analysis are presented in the

technical support document (TSD) for today’s proposed

rule.

PM-10 exceedances were recorded on seven days in the

1992-1994 time period. An analysis of the exceedances,

which includes the spatial plots, windroses, and

trajectories for each of the days, is presented in

Appendix A to the 179B(d) demonstration. EPA’s TSD

27a

discusses in detail each of the days and the basis for

concluding that exceedances would not have occurred

but for transport from Mexico.

For five of the days (August 23, 1993, July 7, 1994,

August 6, 1994, October 17, 1994, and December 16,

1994) the analysis clearly supports the conclusion that

but for the transport of emissions from Mexico, the PM-

10 concentrations would not have exceeded the

standard. The spatial plots for these days indicate a

pattern of higher concentration near the border and

show PM-10 concentrations decreasing with distance

from the border. The windroses for August 23, 1993,

July 7, 1994, August 6, 1994, indicate that a large

number of hours (17 to 19) have the potential to carry

emissions from Mexico to Imperial County.

For two of the exceedance days (January 19, 1993, and

January 25, 1998) there are less data on which to base

an analysis. The days are similar in character. For each

day, there is only one measured value, at the Brawley

monitor, which is slightly more than 20 miles from the

border, so the spatial plot is inconclusive. The days are

classified as stagnant. The windroses show that there is

a potential to carry emissions from Mexico for 14 of 24

hours. The January 19, 1998 PM-10 concentration is

only slightly above the standard (162 g/m\3\), and is

likely to have been influenced by transport, given the

stagnant conditions and the shape of the windrose. A

PM-10 value of 175 g/m\3\ was measured on January 25,

1993. The emissions from Mexico are likely to have

contributed to the PM-10 concentration at the monitor,

although it is difficult to precisely quantify the extent of

the contribution. Given the magnitude of emissions in

the City of Mexicali (see method 4 discussion below), it

28a

is likely that the PM-10 standard would not have been

exceeded but for the contribution of emissions from

Mexico.

Method 2. Comprehensively inventory PM-10 emissions

within the U.S. in the vicinity of the nonattainment

area and demonstrate that the impact of those sources

on the nonattainment area after application of

reasonably available controls does not cause the

NAAQS to be exceeded. This analysis must include an

influx of background PM-10 in the area. Background

PM-10 levels could be based on concentrations

measured in a similar area not influenced by emissions

from outside the U.S.

The 179B(d) demonstration relied on the most recent

gridded modeling inventory available. This inventory

was prepared by CARB as part of the Southern

California Ozone Study, fn3 using 1997 emissions data.

A background concentration of 25 g/m\3\ was used,

based on an analysis of the distribution of observed PM-

10 data in Imperial County. The 25 g/m\3\ value

represents the 10% cleanest days monitored in Imperial

County. The inventory and background level were

included in the modeling analysis discussed under

method 5 below. The 179B(d) demonstration did not

include an analysis of Method 2.

Method 3. Analyze ambient sample filters for specific

types of particles emanating from across the border

(although not required, characteristics of emissions

from foreign sources may be helpful.)

The 1992-1993 Imperial Valley/Mexicali Cross Border

PM-10 Transport Study (Final Report, January 30,

2) eae viaiaariaatas

MR che sc ce a sh SR lla

29a

1997) includes an analysis of the particles collected in

areas within Imperial County where violations have

been recorded. This sample analysis determined that

geological dust (70-90%), motor vehicle exhaust (10-

15%) and vegetative burning (10%) account for the

highest contribution to PM-10 concentrations. These

are the predominant emissions sources on both sides of

the border. Thus, the filter analysis by itself could not

be used to determine the extent to which violations

might result from international transport; however, as

discussed in the TSD, the transport study provided

conclusions about the international contribution based

on a meteorological analysis of airflow in the study

area.

Method 4. Inventory the sources on both sides of the

border and compare the magnitude of PM-10 emissions

originating within the U.S. to those emanating from

outside the U.S.

The 1996 PM-10 emission inventory for the City of

Mexicali, compiled by Radian (Radian International

2000 Mexicali Air Emission Inventory, February 2000)

is of lower quality than the emissions inventory for the

Imperial County sources; however, it is useful for a

comparison of the magnitude of PM-10 emissions from

each side of the border. The estimated emissions for the

City of Mexicali (257 tons/day) are approximately equal

to the PM-10 inventory for Imperial County (246

tons/day). The density of the emissions is much higher

in Mexicali than in Imperial County because the City of

Mexicali covers a much smaller geographic area than

Imperial County. Furthermore, the City of Mexicali is

in close proximity to that portion of Imperial County

where violations have been recorded. This comparison

30a

does not prove PM-10 transport into Imperial County,

but it does suggest that the City of Mexicali has the

potential to be a substantial source contributing to the

PM-10 concentrations in Imperial County because of

the magnitude of the emissions, the density of the

emissions, and the proximity to Imperial County.

Table A.--Comparison of Imperial County and Mexicali

PM-10 Emissions

Imperial County of

County Mexicali

1996 PM-10

Emissions

(tons/day)......+- 246 257

Population

bre 142,361 662,617

INBIOS. ...00sccceecee 4060 200

Growth rate in

percent

(1999-2000)... 30 42

Source: 1996 PM-10 emission inventory for the City of

Mexicali, compiled by Radian (Radian International

2000 Mexicali Air Emission Inventory, February 2000).

Method 5. Perform air dispersion and/or receptor

modeling to quantify the relative impacts on the non-

attainment area of sources on PM-10 emissions.

The 179B(d) demonstration includes air dispersion

modeling for 1992, 1993 and 1994. The modeling inputs

(meteorological data and inventory), model selection

and modeling results are discussed in the TSD. The

performance of the model relative to measured ambient

3la

concentrations could not be determined because

emissions from Mexicali were not modeled. Therefore,

EPA cannot evaluate the model performance and, as a

result, the Agency believes that the modeling results

are not sufficiently robust at this time to demonstrate

that Imperial County would have been in attainment of

the 24-hour PM-10 standards but for PM-10 emissions

from Mexico.

The results of the modeling are more useful for the

demonstration of the annual standard, which is less

sensitive to model inputs. The annual arithmetic mean

for the Brawley monitoring station for the years 1992-

1994 is only slightly above the annual standard, (51

g/m’), and this part of the basin is therefore likely to

have attained the standard, but for international

transport. The Calexico-Grant St. and Calexico-Ethel

St. sites are in close proximity to the border. The

Calexico Grant St. annual average was 56 g/m’. The

Calexico-Ethel St. site, which hu only partial data, has

an annual average design value of 120 g/m’ in 1994,

after adjustments upward for missiag data. The

modeling results (included in the TS}: also indicate

that the annual standard would have be 2n attained for

each year from 1992-1994 at each of the Calexico

sites.fn4 Based on the proximity to the border, the

magnitude of the Mexicali emissions and the modeling

results, EPA believes, that the annual standard vould

have been attained at these sites but for transport.

Summary of EPA Evaluation of 179B(d) Demonstration

The State’s demonstration is based on a competently

collected and examined set of the relevant available

information, and reaches a reasoned conclusion that

32a

each of the 1992-94 exceedances, which are only slightly

above the NAAQS, would likely not have occurred

without pollutant transport from Mexico. However, In

reviewing the methods for determining international

transport, EPA lacks some information that would be

helpful in determining with greater certainty the

extent to which emissions from Mexico contributed to

monitored values above the NAAQS. For example, the

State was hampered by the absence of ambient

monitoring or accurate emission inventories in the

Mexicali area in the period 1992-94. These data cannot

now be recreated in order to enable a more conclusive

analysis. Thus, EPA believes that the 179B(d)

demonstration has provided evidence sufficient to show

that, but for international transport of PM-10, Imperial

County would have attained the 24-hour PM-10

NAAQS by the December 31, 1994 deadline. This

showing rests primarily on the qualitative analysis of

wind patterns on exceedance days discussed under

method 1 and is further supported by the emissions

inventories discussed under method 4. Furthermore,

EPA believes the modeling discussed under Method 5

provides a demonstration that the annual PM-10

NAAQS has been attained but for international

transport.

If EPA takes final action finding that the State has met

the requirements of CAA section 179B(d), Imperial

County must meet the planning requirements specified

in CAA section 179B(a). Because the area has recorded

PM-10 violations after 1994, EPA interprets the latter

section as requiring, among other things, that the

moderate area plan must provide for sufficient controls

to demonstrate maintenance of the NAAQS after the

33a

applicable attainment date, but for emissions from

outside of the United States.

III. Proposed Finding of Failure To Attain

As discussed above, EPA is proposing to find that the

State of California has established to EPA’s satisfaction

that Imperial County would have attained the NAAQS

for PM-10 by the applicable attainment date, December

31, 1994, but for emissions emanating from outside the

U.S., and thus shall not be subject to a finding of failure

to attain and reclassification. Because the 179B(d)

demonstration is not completely definitive, however,

_EPA invites public comment on the issue and is

proposing, in the alternative, to find that Imperial

County did not attain either the 24-hour or annual PM-

10 NAAQS by December 31, 1994. In the event that

public comments convince EPA that the State has not

made an adequate demonstration under section 179B(d)

of the CAA, EPA plans to finalize this proposed finding

of failure to attain. This proposed finding is based on air

quality data (discussed below) indicating violations of

the PM-10 NAAQS during 1992-1994. If EPA takes

final action on this proposed finding, Imperial County

will be reclassified by operation of law as a serious

nonattainment area under section 188(b)(2)’A) of the

CAA.

34a

A. Analysis of the Ambient Air Monitoring Data

The 24-hour Standard

Table C below lists each of the monitoring sites in

Imperial County where the 24-hour NAAQS (150 g/m?)

was violated during 1992-1994.

Note: There is no Table B in this proposed rule.

Table C.--Exceedance Values for Sites Violating the 24-

hour PM-10 NAAQS

[Micrograms per cubic meter, g/m*]

Date of

Site Exdeedance exceedance

Brawley..........cecccccecscess 175 Mpg/m? = 1/25/98

162 g/m? 1/19/93

Calexico Dichot--900

Grant Street...........+0+ 208 pg/m?* 10/9/92

253 pg/m?* 8/23/93

156 pg/m? 1/20/94

El Centro0........cccccccsesese 166 pg/m* 8/23/93

El Centro Dichot............ 167 pg/m’° 8/23/93

Calexico--900 Grant St.

(initiated 1994)............ 182 pg/m® 8/6/94

165 pg/m® 7/7/94

159 pg/m? 10/17/94

Calexico--1029 Ethel St

(initiated 1994)............ 258 pg/m? 8/6/94

Under 40 CFR part 50, the 24-hour NAAQS is attained

when the expected number of days per calendar year

with a 24-hour average concentration above 150 g/m? is

equal to or less than one. In general, the number of

expected exceedances at a site which samples every

;

PRN eye 82

Bir By ew od

ey Cr”

x: 5c DCA

Bs,

35a

day is determined by recording the number of

exceedances in each calendar year and then averaging

them over the past three calendar years. For sites

which do not sample every day, EPA requires the

adjustment of observed exceedances to account for

days not sampled. The procedures for making the

adjustment are specified in 40 CFR part 50, appendix

The four monitoring sites (Brawley, Calexico-Dichot, El

Centro, and El Centro-Dichot) in Imperial County that

recorded violations of the 24-hour PM-10 NAAQS

operated on a one-in-six day sampling schedule. After

making the adjustment for days not sampled, the

number of expected exceedances from 1992-1994 at four

of the above monitoring sites were 4.3, 6.1, 2.0 and 2.0,

for the Brawley, Calexico Dichot--Grant St., E] Centro

and El Centro Dichot sites, respectively. These

expected exceedances cause the four monitoring sites

to be in violation of the 24-hour PM-10 NAAQS. EPA is

also including data from two additional samplers

(Calexico--Grant St. and Calexico--Ethel St.) which

exceeded the 24-hour PM-10 NAAQS in their initial

year of operation, 1994.

The Annual Standard

Table D below lists each of the monitoring sites where

the annual standard was violated during 1992-1994.

36a

Table D.--Arithmetic Mean Values for

Sites Violating the Annual PM-10 NAAQS

[Micrograms per cubic meter, g/m*]

1992 1993 1994

annual annual annual

Site arithmetic arithmetic arithmetic

mean mean mean

Brawley........+ 48 pg/m* 53 pg/m* 52 pg/m*

Calexico............. 58 pg/m* 59 pg/m* 50 pg/m*

Dichot—900

Grant St.

Calexico—900... ND.......... |) 75 pg/m®

Grant St.

(initiated

1994)

Calexica—1029. ND.......... |) er 120 pg/m?

Ethel St.

(initiated

1994)

ND--No Data.

According to 40 CFR part 50, the annual standard for

PM-10 is attained when the expected arithmetic mean

concentration, as determined by 40 CFR part 50

Appendix K, is less than or equal to 50 g/m\B\ In

general, the expected annual arithmetic mean is

determined by averaging the annual arithmetic mean

PM-10 concentrations for the past 3 calendar years.

The annual standard was not attained at two

monitoring sites (Brawley and Calexico Dichot--Grant

St.) in Imperial County. Based on the monitoring data

collected during 1992-1994, the Brawley site had an

annual average of 51 g/m\3\, and the Calexico Dichot--

37a

Grant St. had an annual average of 56 g/m\3\. EPA is

also including data from 2 additional samplers

(Calexico--Grant St. and Calexico--Ethel St.) which

violated the annual PM-10 NAAQS and were initiated

in 1994.

B. SIP Requirements for Serious Areas

If EPA takes final action finding that Imperial County

failed to attain the PM-10 NAAQS by December 31,

1994, the area will be reclassified by operation of law as

a serious nonattainment area under section 188(b)(2)(A)

of the CAA. PM-10 nonattainment areas reclassified as

serious under section 188(b)(2) of the CAA are required

to submit, within 18 months of the area’s

reclassification, SIP revisions providing for the

implementation of best available control measures

(BACM) no later than four years from the date of

reclassification. The SIP must also, among other things,

provide for attainment of the PM-10 NAAQS by

December 31, 2001.fn5 See CAA sections 188(c)(2) and

189(b). EPA has provided specific guidance on

developing serious area PM-10 SIP revisions. See 59

FR 41998 (August 16, 1994).

IV. Today’s Proposed Actions

EPA is today proposing to find that the State of

California has established to EPA’s satisfaction that

Imperial County has attained the PM-10 NAAQS by

the applicable attainment date, December 31, 1994, but

for the emissions emanating from outside the U.S., and

thus shall not be subject to a finding of failure to attain

and reclassification to serious.

38a

In view of the technical issues and difficulties involved

in demonstrating cross-border transport and in the

event that public comment convinces EPA that the

State has not made an adequate demonstration, EPA is

also proposing, in the alternative, to find that Imperial

County did not attain either the 24-hour or annual PM-

10 NAAQS by the required attainment date. If EPA

takes final action on this proposed finding, Imperial

County will be reclassified by operation of law as a

serious nonattainment area under section 188(b)(2)(A)

of the CAA.

EPA requests public comments on all aspects of these

alternative proposals. EPA will consider any comments

received by September 10, 2001.

V. Administrative Requirements

A. Executive Order 12866

Under E.0. 12866, 58 FR 51735 (October 4, 1993), EPA

is required to determine whether regulatory actions are

significant and therefore should be subject to OMB

review, economic analysis, and the requirements of the

Executive Order. The Executive Order defines a

“significant regulatory action” as one that is likely to

result in a rule that may meet at least one of the four

criteria identified in section 3(f), including, (1) have an

annual effect on the economy of $100 million or more or

adversely affect, in a material way, the economy, a

sector of the economy, productivity, competition, jobs,

the environment, public health or safety, or State, local,

or tribal governments or communities; (2) create a

serious inconsistency or otherwise interfere with an

action taken or planned by another agency; (3)

4 peaeees es a 4

ARCA G BBs BH Sc Ar ides aa

39a

materially alter the budgetary impact of entitlements,

grants, user fees, or loan programs or the rights and

obligations of recipients therof; or (4) raise novel legal

or policy issues arising out of legal mandates, the

President’s priorities, or the principles set forth in the

Executive Order.

EPA has determined that the proposed finding of

attainment pursuant to CAA section 179B(d) and the

proposed finding of failure to attain and the resulting

reclassification would result in none of the effects

identified in section 3(f). A finding of attainment under

section 179B(d) of the CAA does not impose any

additional requirements on an area and a finding of

failure to attain under section 188(b)(2) is based upon

air quality considerations and the subsequent

nonattainment area reclassification must occur by

operation of law in light of those air quality conditions.

These actions do not, in-and-of-themselves, impose any

new requirements on any sectors of the economy. In

addition, because the statutory requirements are

clearly defined with respect to the differently classified

areas, and because’ those’ requirements are

automatically triggered by classifications that, in turn,

are triggered by air quality values, findings of failure to

attain and reclassification cannot be said to impose a

materially adverse impact on State, local, or tribal

governments or communities.

B. Executive Order 13211

The proposed finding of attainment under CAA 179B(d)

and the proposed finding of failure to attain and the

resulting reclassification are not subject to Executive

Order 13211, “Actions Concerning Regulations That

40a

Significantly Affect Energy Supply, Distribution, or

Use” (66 FR 28355 (May 22, 2001)) because they are not

significant regulatory actions under Executive Order

12866.

C. Executive Order 13045

Executive Order 13045, entitled Protection of Children

from Environmental Health Risks and Safety Risks (62

FR 19885, April 23, 1997), applies to any rule that: (1) Is

determined to be “economically significant” as defined

under Executive Order 12866, and (2) concerns an

environmental health or safety risk that EPA has-

reason to believe may have a disproportionate effect on

children. If the regulatory action meets both criteria,

the Agency must evaluate the environmental health or

safety effects of the planned rule on children, and

explain why the planned regulation is preferable to

other potentially effective and reasonably feasible

alternatives considered by the Agency.

The proposed finding of attainment under CAA 179B(d)

and the proposed finding of failure to attain under CAA

188(b)(2) and resulting reclassification are not subject

to Executive Order 13045 because they do not involve

decisions intended to mitigate environmental health or

safety risks.

D. Executive Order 131382

Executive Order 13182, “Federalism,” (64 FR 48255,

August 10, 1999) revokes and replaces Executive

Orders 12612, “Federalism,” and 12875, “Enhancing the

Intergovernmental Partnership.” Executive Order

ay)

4la

13132 requires EPA to develop an accountable process

to ensure “meaningful and timely input by State and

local officials in the development of regulatory policies

that have federalism implications.” “Policies that have

federalism implications” is defined in the Executive

Order to include regulations that have “substantial

direct effects on the States, on the relationship between

the national government and the States, or on the

distribution of power and responsibilities among the

various levels of government.” Under Executive Order

13132, EPA may not issue a regulation that has

federalism implications, that imposes substantial direct

compliance costs, and that is not required by statute,

unless the Federal government provides the funds

necessary to pay the direct compliance costs incurred

by State and local governments, or EPA consults with

State and local officials early in the process of

developing the proposed regulation. EPA also may not

issue a regulation that has federalism implications and

that preempts State law unless the Agency consults

with State and local officials early in the process of

developing the proposed regulation.

These proposed findings will not have substantial direct

effects on California, on the relationship between the

national government and California, or on the

distribution of power and responsibilities among the

various levels of government, as specified in Executive

Order 13132. As stated above, a finding of attainment

under section 179B(d) of the CAA does not impose any

additional requirements on an area and a finding of

failure to attain under section 188(b)(2) is based upon

air quality considerations and the subsequent

nonattainment area reclassification must occur by

operation of law in light of those air quality conditions.

42a

These actions do not, in-and-of-themselves, impose any

new requirements on any sectors of the economy. In

addition, because the statutory requirements are

clearly defined with respect to the differently classified

areas, and because those requirements are

automatically triggered by classifications that, in turn,

are triggered by air quality values, findings of failure to

attain and reclassification cannot be said to impose a

materially adverse impact on State, local, or tribal

governments or communities. Thus, the requirements

of section 6 of the Executive Order do not apply to

these proposed alternative actions.

E. Executive Order 13175

Executive Order 13175, entitled “Consultation and

Coordination with Indian Tribal Governments” (65 FR

67249, November 6, 2000), requires EPA to develop an

accountable process to ensure “meaningful and timely

input by tribal officials in the development of

regulatory policies that have tribal implications.”

“Policies that have tribal implications” is defined in the

Executive Order to include regulations that have

“substantial direct effects on one or more Indian tribes,

on the relationship between the Federal government

and the Indian tribes, or on the distribution of power

and responsibilities between the Federal government

and Indian tribes.”

The proposed finding of attainment under CAA 179B(d)

and the proposed finding of failure to attain under CAA

188(b)(2) and resulting reclassification do not have

tribal implications. For the reasons discussed above,

they will not have substantial direct effects on tribal

governments, on the relationship between the Federal

43a

government and Indian tribes, or on the distribution of

power and responsibilities between the Federal

government and Indian tribes, as specified in Executive

Order 13175. Thus, Executive Order 13175 does not

apply to this rule. In the spirit of Executive Order

13175, and consistent with EPA policy to promote

communications between EPA and tribal governments,

EPA specifically solicits additional comment on this

proposed rule from tribal officials.

F. Regulatory Flexibility Act

The Regulatory Flexibility Act (RFA) generally

requires an agency to conduct a regulatory flexibility

analysis of any rule subject to notice and comment

rulemaking requirements unless the agency certifies

that the rule will not have a significant economic impact

on a substantial number of small entities. Small entities

include small businesses, small not-for-profit

enterprises, and small governmental jurisdictions.

As discussed above, the proposed finding of attainment

under CAA 179B(d) and the proposed finding of failure

to attain under CAA 188(b)(2) and_ resulting

reclassification do not impose additional requirements

on small entities. Therefore, I certify that these

alternative actions will not have a significant economic

impact on a substantial number of small entities.

G. Unfunded Mandates

Under section 202 of the Unfunded Mandates Reform

Act of 1995 (“Unfunded Mandates Act”), signed into

law on March 22, 1995, EPA must prepare a budgetary

impact statement to accompany any proposed or final

44a

rule that includes a Federal mandate that may result in

estimated costs to State, local, or tribal governments in

the aggregate; or to the private sector, of $100 million

or more. Under section 205, EPA must select the most

cost-effective and least burdensome alternative that

achieves the objectives of the rule and is consistent

with statutory requirements. Section 203 requires EPA

to establish a plan for informing and advising any small

governments that may be significantly or uniquely

impacted by the rule.

With respect to EPA’s proposed finding of attainment

under CAA 179B(d) and the proposed finding of failure

to attain under CAA 188(b)(2) and resulting

reclassification, EPA notes that these actions in-and-of

themselves establish no new requirements, and EPA

believes that it is questionable whether a requirement

to submit a SIP revision constitutes a federal mandate

(i.e., required serious area SIP submittal resulting from

a finding of failure to attain). The obligation for a State

to revise its SIP arises out of sections 110(a) and 179(d)

of the CAA and is not legally enforceable by a court of

law, and at most is a condition for continued receipt of

highway funds. Therefore, it is possible to view an

action requiring such a submittal as not creating any

enforceable duty within the meaning of section

421(5)(9a)(1) of UMRA (2 U.S.C. 658(a)(I)). Even if it

did, the duty could be viewed as falling within the

exception for the condition of Federal assistance under

658(5)(a)(I)(1)).

In addition, even if the obligation for a State to revise

its SIP does create an enforceable duty within the

meaning of UMRA, this action does not trigger section

4 a

3 a

NER REE Seabee pt a racipitigaen ts

en een ee

SE I LE CS

45a

202 of UMRA because the aggregate to the State, local,

and tribal governments to comply are less than

$100,000,000 in any one year. Because this action does

not trigger section 202 of IJMRA, the requirement in

section 205 of UMRA that EPA identify and consider a

reasonable number of regulatory alternatives and adopt

the least costly, most effective, or least burdensome

alternative that achieves the objectives of the rule is

not applicable.

Furthermore, EPA is not directly establishing any

regulatory requirements that may significantly impact

or uniquely affect small governments, including tribal

governments. Thus, EPA is not obligated to develop

under section 203 of UMRA a small government agency

plan.

H. National Technology Transfer and Advancement

Act

Section 12 of the National Technology Transfer and

Advancement Act (NTTAA) of 1995 requires Federal

agencies to evaluate existing technical standards when

developing a new regulation. To comply with NTTAA,

EPA must consider and use “voluntary consensus

standards” (VCS) if available and applicable when

developing programs and policies unless doing so would

be inconsiste... with applicable law or otherwise

impractical.

EPA believes that VCS are inapplicable to today’s

proposed actions because they do not require the public

to perform activities conducive to the use of VCS.

46a

List of Subjects in 40 CFR Part 81

Environmental protection, Air pollution control,

National parks, Wilderness areas.

Authority: 42 U.S.C. 7401-7671q.

Dated: August 6, 2001.

Laura Yoshii,

Acting Regional Administrator, Region IX.

[FR Doc. 01-20209 Filed 8-9-01; 8:45 am]

BILLING CODE 6560-50-P

Footnotes

fnl In his letter, Mr.Kenny state’s that CARB “worked

closely with the Imperial County Air Pollution Control

District * * * in developing their analysis, and agree

with their conclusion that the area would have attained

the standard from 1992 through 1994 but for transport

from Mexico. Independent Air Resources Board

analyses of all exceedances in that time frame support

the District’s conclusion.” Because CARB has ratified

the ICAPCD’s 179B(d) demonstration and transmitted

it to EPA, it is referred to in this proposal as the State’s

demonstration.

fn2 “State Implementation Plans for Serious PM-10

Nonattainment Areas, and Attainment Date Waivers

for PM-10 Nonattainment Areas Generally; Addendum

to the General Preamble for the Implementation of

Title I of the Clean Air Act Amendments of 1990,” 59

FR 41998, August 16, 1994.

cL ee

Fae eS sch «ais LG eS a

APT

tia

fn3 The Southern California Ozone Study (SCOS) was a

large-scale field measurement program carried out in

southern California during the summer of 1997 to

collect sufficient aerometric data to allow data analysts

and modelers to characterize and simulate ozone

formation and fate in the region. Several agencies and

others participated during the planning and operational

phases of the field study, including CARB, EPA, local

districts, the U.S. Navy, and the marine industry.

fn4 Modeled annual average concentrations at all of the

sites are below 43 g/m\3\ for each of the 3 years,

assuming only emissions from the United States side of

the border.

fn5 If certain conditions are met, EPA may extend this

attainment deadline to no later than December 31, 2006.

CAA section 188(e).

48a

Imperial County, California PM-10

Nonattainment Area

Proposed Finding of Attainment of the 24-hour and

Annual PM-10 Standards

But For the Emissions Emanating from Mexico; And

Alternative Proposed Finding of Failure to Attain the

94-hour and Annual PM-10 Standards.

Technical Support Document

(Proposed Finding of Attainment under Clean Air

Act Section 1798(d)-

Additional Discussion of Method | and Method 5)

August 10, 2001

Authors:

Doris Lo, EPA Region 9, Air Division

Carol Bohnenkamp, EPA Region 9, Air Division

49a

Table of Contents

z. RE ne Lea aT 1

II. Proposed Finding of Attainment under

CAA _ Section 1798(d) Additional

Discussion of Method | and-method 5................... 2

A. NE 9 ict ssacassemenmionlaaielerasavenedaaniinasennsauns 2

1) January 19, 1993 (162 jg/m?* at

SI wosactsiaseiscacennteisteeddnakveshiccasabateiAinipiainaaiantce 3

2) January 25, 1993 (175 pg/m’ at Brawley)......... 4

3) August 23, 1993 (166 g/m’ at Brawley’)........ 5

4) July 7, 1994 (165 pg/m? at Calexico-

is Wc tisiccs asinleeesbiceunccnoeetasaecdciuintancetcccens 6

5) August 6, 1994 (258 pg/m* and 182 pg/m?

at Calexico-Ethel St. and Calexico-Grant

Fig MII Es sscsacisiatiscidisihdaiiccaohandaiiviaenadncencenes 6

6) October 17, 1994. (159 g/m? at.

Calexico-Grant St.) .............: ie hashieeenintinsdinannns 6

7) December 16, 1994 (153 jg/m* at

CR TER bic Dcssicssncisconanitsstacnninstinisialinicistimeassons 7

B. Eiichi 5a iiiotis caherineiscsichaleansipassedaddosatacbeatisianicte 7

RL} MROCOOR ONION TIRE isccscscisscsessecesecesnsssenstersnreases 8

BF I II oss ies cicnsnsesacidsnsedsnaisasnnasessbinsion 8

o) DOCOTIE TRV OTEONG sisi ccecssesssssscssressecsacacasevesics 9

5) CUNT TOUS oss scecscsnsescsnscsnsussoorussvonseernces 9

ins

Attachments:

Attachment 1: Imperial. County PM10 Attainment

Demonstration; Prepared for Imperial County Air

Pollution Control District by ENVIRON, July 20-01,

50a

transmitted to EPA by the California Air Resources

Board on July 18, 2001.

Attachment 2: Additional windroses and windfields for

January 25, 1993; transmitted to Carol Bohnenkamp,

EPA Region 9, Air Division by Ralph Morris,

ENVIRON.

I. Introduction

On August 6, 2001, EPA issued two alternative

proposals:

1) EPA proposed to find that the State of California

__ has established to EPA’s satisfaction that Imperial

County, a PM-10 moderate nonattainment area,

would have attained the national ambient-air quality

standards (NAAQS) for particulate matter of ten

microns or less (PM-10) by the applicable Clean Air

Act (CAA or the Act) attainment date, December 31,

1994, but for emissions emanating from outside the

United States, ie., Mexico. This proposed finding is

based on the “Imperial County PM10 Attainment

Demonstration,” (Attachment 1, also referred to as

the State’s demonstration or the 179B(d)

demonstration) provided to EPA by the State of

California. If EPA takes final action on this

proposed finding, Imperial County will not-be

subject to a finding of failure to attain and

reclassification to serious.

2) Alternatively, EPA proposed to find that Imperial

County did not attain the PM-10 NAAQS by its CAA

mandated attainment date. This proposed finding is

based on monitored air quality data for the PM-10

PALI TAS sb ir? at SRR TA AE

jacinta Nee seacoast

PLE AMAR DT NE PPE hs ath ests

Sethe See Re APC re

AER SORA I EERE

5la

NAAQS during the years 1992-1994. If EPA takes

final action on this proposed finding, Imperial

County will be reclassified by operation of law as a

serious nonattainment area under section 188 (b) (2)

(A) of the CAA.

These proposed alternative actions were published

in a Federal Register notice (66 FR 42187) on

August 10, 2001 (notice of proposed rulemaking or

NPR). The 30 day public comment period will end on

September 10, 2001. EPA intends, to issue a final

action shortly thereafter.

EPA is, requesting public comments on both

proposals. The purpose of this technical support

document (TSD) is to supplement the NPR’s

discussion of the proposed finding of attainment

under CAA section 179B(d), specifically Methods 1

and 5.

As discussed in the NPR, EPA is proposing to find

that the State has established to EPA's satisfaction

that the Imperial County moderate PM-10

nonattainment area would have attained the annual

and 24-hour NAAQS for PM-10 by the applicable

attainment date, 1994, but for the emissions emanating

from Mexico. This proposed finding is based on the

“Imperial County PM10 Attainment Demonstration”

which was transmitted to EPA by the California Air.

Resources Board on July 18, 2001 (Attachment 1, also

referred to as the 179B(d) demonstration) and

“additional windroses and windfields for January 25,

1993” which was transmitted to Carel Bohnenkamp,

EPA Region 9, Air Division by Ralph Morris,

ENVIRON (Attachment 2). EPA’s analysis of how

52a

these documents meet CAA section 179B(d) and

EPA’s General Preamble guidance fnl is found in the

NPR. In addition to the NPR discussion, EPA is

below providing a more detailed day-by-day analysis

which supports its conclusions regarding Method 1 and

a summary of the modeling which was performed for

Imperial County. to support the conclusion for the

annual PM-10 standard under Method 5.

A. Method 1

In EPA’s General Preamble guidance, the first

suggested method (Method 1) for determining the

impact of emissions emanating from outside the U.S. is

to “[pllace several ambient PM-10 monitors and a

meteorological station measuring wind speed and

direction in the U.S. non attainment area near the

international-border . . . [and] [e]lvaluate and quantify

any changes in monitored PM-10 concentrations with a

change in direction in the predominant wind

direction.”

As discussed in the NPR, there are six PM-10

monitors fn2 in the nonattainment area, with two

monitors in the proximity of the border (Calexico-

Grant St. and Calexico-Ethel St., each 1.2 km from the

Mexican border). A meteorological station at the

Imperial County Airport was used to provide a

windrose fn3 for each exceedance day. The 179B(d)

demonstration provided, for each exceedance day, an

analysis of the transport of PM-10 from Mexico, based

on the spatial distribution of PM-10 throughout the

basin, along with a windrose, and a series of back

trajectories (based on the National Oceanic and

Atmospheric Administration HYSPLIT program).

“1

ret

SS,

53a

(The spatial plots, windroses and trajectories .are

included in Appendix A to Attachment 1.) The NPR

provides a summary of the day-by-day analysis

presented below.

PM-10 concentrations were recorded on seven days in

the 1992-1994 time period. Each of the seven days

which recorded a PM-10 concentration which exceeded

the 24-hour PM-10 standard is discussed below. For

each exceedance day, EPA first restates the analysis

presented by the State, then, where relevant, EPA

summarizes the analysis provided by the Imperial

Valley/Mexicali Cross Border PM-10 Transport

Study.fn4 This is followed by EPA’s’ conclusion.

1) January 19, 1993 (162 g/m? at Brawley)

State’s Demonstration: There is only one data point for

the spatial plot (Brawley). The windrose for this day

shows that there are 15 out of 24 hours with southerly

wind directions that have the potential to carry.

emissions from Mexico into Imperial County. The back

trajectories based on upper-air synoptic wind data

suggest much higher winds and back trajectories that

do not pass through Mexicali. The day is classified as a

stagnant air day, therefore there is more separation

between the surface winds and the winds aloft and

greater weight is given to the surface data. The

windrose suggests that emissions from Mexico

contributed to the concentration measured at Brawley.

Because the PM-10 exceedance on this day occurs

when only one site was operating, there is insufficient

information to draw any additional conclusions.

However, given the closeness of the exceedance to the

standard and the presence of surface winds with a

54a

southerly wind component for over half the day, it

appears likely that this exceedance would not have

occurred but for transport from Mexico.

Summary of Imperial Valley/Mexicali Cross

Border PM-10 Transport Study: The Imperial

Valley/Mexicali Cross Border PM-10 Transport

Study states that [.... 01/19/93... .] was associated

with stagnation conditions, and little transport took

place. On [this] day, Calexico and Mexicali emissions

might mingle on both sides of the border. It is unlikely,

however, that sites in E] Centro and Brawley would

receive significant contributions from Mexican

sources.”

EPA Conclusion: EPA concurs with the State’s

conclusion that, given the number of hours with a

southerly wind direction, and the closeness of the

exceedance to the standard, it is likely that, but for

transport from Mexico, this exceedance would not

have occurred.

2) January 25, 199.3 (175 g/m’? at Brawley)

State’s Demonstration: There is only one data point for

the spatial plot (Brawley). The windrose for this day

shows that there are 14 out of 24 hours with wind

direction that have the potential to carry emissions

from Mexico into Imperial County. The back

trajectories suggest very high wind speeds that are

obviously decoupled from the surface winds, which are

very low. The day is classified as a stagnant air day.

The windrose suggests that emissions from Mexico

contributed to the concentration measured at Brawley.

55a

This day is very similar in character to January 23,

1993 and the same conclusions apply.

Attachment 2 includes additional windroses for

Imperial County and a more detailed analysis of

windfields on January 25, 1993, indicating conditions

that are “fairly stagnant in the lower half of Imperial

County with a fairly significant southerly component

that occurs 30% to 50% of the hours during the day.

The CALMET windfields also suggest stagnant

conditions with the winds ill defined but some

southerly flow that suggests emissions from Mexico

(south of UTMN 3615-km) likely were transported to

the Brawley PM monitor (roughly 635-km UTME

by 3650-km,UTMN). Given the amount of the PM

emissions in Mexicali, the stagnant wind

conditions in southern Imperial County, and the

closeness the exceedance to the standard (175 pg/m*)

. . .»” Imperial County is likely to have attained but

for transport from Mexico. The additional windroses

and CALMET windfields are _ presented in

Attachment 2.

Summary of Imperial Valley/Mexicali Cross Border

PM-10 Transport Study: The Imperial Valley/Mexicali

Cross Border PM-10 Transport Study states that “...

January 25, 1993 had consistent flow from the

northwest, which rules out transport from Mexico.”

EPA Conclusion: Based on the more detailed windfield

analysis, EPA concurs with the State’s conclusion that

there are stagnant conditions in southern Imperial

County. Therefore, EPA believes that the State has

presented a plausible analysis that the emissions from

Mexico are likely to have contributed to the

56a

concentrations measured at Brawley so that there

would have been attainment but for transport.

3) August 23, 1993 (166 pg/m’ at El Centro)

State’s Demonstration: The spatial plot only has two

data points at El Centro and Brawley but the more

southerly monitor (El Centro) shows a much higher

concentration. The windrose for that day shows that

there are 19 out of 24 hours with wind directions that

have the potential to carry emissions from Mexico into

Imperial County and the back trajectory also shows

that winds aloft carried air from Mexico into Imperial

County. The day is not classified as a stagnation day,

suggesting that the windrose and back trajectory are

accurate. All analyses suggest that emissions from

Mexico are impacting monitors in Imperial County.

Summary of Imperial Valley/Mexicali Cross Border

PM-10 Transport Study: The Imperial Valley/Mexicali

Cross Border PM-10 Transport Study states that

“August 23, 1993 appeared to be dominated by

transport.”

EPA Conclusion: The spatial plot and windrose clearly

show the potential for transport. The proximity to the

border and the small magnitude of the exceedance

support that, but for transport from Mexico, the PM-10

standard would have been attained.

4) July 7, 1994 (165 pg/m? at Calexico-Grant St.)

State’s Demonstration: The spatial plot shows an

exceedance at Calexico-Grant St. that is more than

two times higher than any monitor in Imperial County.

57a

The windrose shows that there are 17 out of 24 hours

with wind directions that have the potential to carry

emissions from Mexico into Imperial County and the

back trajectory also shows that winds aloft carried’ air

from Mexico into Imperial County. The day is classified

as -a stagnation day, suggesting that the windrose and

back trajectory should be interpreted cautiously. The

analyses, however, still strongly suggest that emissions

from Mexico are impacting monitors in Imperial

County.

EPA Conclusion: The spatial plot, the proximity of the

Calexico-Grant St. monitor to the Mexican border, and

windrose strongly support that, but for transport from

Mexico, the PM-10 standard would have been attained.

5) August 6, 1994 (258 pg/m* and182 pg/m? at Calexico-

Ethel St. and Calexico-Grant St., respectively)

State’s Demonstration: The spatial plot shows

exceedances at Calexico-Ethel St. and Calexico-Grant

St., one of which is more than double the

concentrations measured at more northerly sites in

Imperial County. The windrose shows that there are

18 out of 24 hours with wind directions that have the

potential to carry emissions from Mexico into Imperial

County and the back trajectory also shows that winds

aloft carried air from Mexico into Imperial County.

The day is not classified as a stagnation day. All

analyses suggest that emissions from Mexico are

impacting monitors in Imperial County.

IRON RSE as ia en aa a ‘

EPA Conclusion: The spatial plot and windrose

support that, but for transport from Mexico, the PM-10

standard would have been attained.

58a

6) October 17, 1994 (159 pg/m? at Calexico-Grant St.)

State’s Demonstration: The spatial plot shows

decreasing concentrations moving north from

Calexico. The windrose shows that there are 14 out of

24 hours with wind directions that have the potential

to carry emissions from Mexico into Imperial County.

The back trajectories do not show air being carried

from outside of the U.S. to the impacted location. The

dey, however, is classified as a stagnant air day,

therefore, there is more separation between the

surface winds and the winds aloft and greater weight

is given to the surface data. The single high PM10

concentration at Calexico-Grant St., which is in close

proximity to Mexico, and windrose strongly suggest

that this exceedance is likely due to emissicns from

Mexico.

EPA Conclusion: The spatial plot and windrose

support that, but for transport from Mexico, the PM-

10 standard would have been attained. In addition,

the measured value is only slightly over the standard

and in close proximity of the border.

7) December 16, 1994 (153 pg/m’ at Calexico-Ethel St.)

State’s Demonstration: The spatial plot shows

decreasing concentrations moving north from

Calexico. The windrose shows that there are 14 out of

94 hours with wind directions that have the potential

to carry emissions from Mexico into Imperial County.

The back trajectories do not show air being carried

from outside of the U.S. to the impacted location. The

day, however, is classified as a stagnant air day,

therefore there is more separation between the

59a

surface winds and the winds aloft and greater weight

is given to the surface data. The single high PM10

concentration at Calexico-Ethel St., which is in close

proximity to Mexico, and windrose suggest that this

exceedance is potentially due to emissions from

Mexico.

EPA Conclusion: The spatial plot and windrose

support that, but for transport from Mexico, the PM-

10 standard would have been attained. In addition, the

measured value is slightly under the standard and in

close proximity of the border.

B. Method 5

In EPA’s General Preamble guidance, the fifth

suggested method (Method 5) for determining the

impact of emissions emanating from outside the U.S. is

to. “[p]erform air dispersion and/or receptor modeling

to quantify the relative impacts on the non-attainment

area of sources on PM-10 emissions.”

As discussed in the NPR, the State’s 179B(d)

demonstration included air dispersion modeling

performed for 1992, 1993 and 1994. The dispersion

modeling which used the emissions inventory for

Imperial County and a_ reasonable background

concentration of 25 pg/m* showed that Imperial County

- would have been in attainment of both the annual and

24-hour PM-10 standards but for PM-10 emissions from

Mexico. However, the performance of the model

relative to measured ambient concentrations could not

be determined because emissions from Mex?cali were

not modeled. Therefore, the model performance could

not be assessed by EPA, and, as a result, the Agency

60a

believes that the modeling results are not sufficiently

robust at this time to demonstrate that Imperial

County would have been in attainment of the 24-hour

PM-10 standards but for PM-10 emissions from

Mexico.

The results of the modeling are more useful for the

demonstration of the annual standard, which is less

sensitive to model inputs. As discussed in the NPR,

the moceling results indicate that the annual PM-10

standard would have been attained for each year from

1992-1994 at each of the monitoring sites Based on

the proximity to the border, the magnitude of the

Mexicali emissions and the modeling results, EPA

believes, that the annual standard would have been

attained at these sites but for the emissions from

Mexico. The modeling inputs (meteorological data and

inventory), model selection and modeling results

(fable A and B) are discussed below.

1) Meteorological Data

The State’s 1798 (d) demonstration used surface

meteorological-data from the Imperial County

Airport, with additional surface data from Calexico

and Mexicali. Upper air data from San Diego

(Miramar) and Tucson were also used.

2) Model Selection

The State’s 179B(d) demonstration used the

CALMET/CALPUFF modeling system for the

179B(d) demonstration. The selection of the modeling

system was based on the _ ability of

CALMET/CALPUFF to treat stagnation conditions

z '

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and its ability to process a large number. of days

which was necessary to complete the analysis. The

CALMET/CALPUFF modeling system offers a

simplified treatment of secondary particulates, which

is appropriate, given the small contribution of

secondary particulates to exceedances in the Imperial

County. EPA concurs that the model selection was

appropriate.

3) Modeling Inventory

The 1997 modeling inventory was derived from the

CARB Southern California Ozone Study modeling

inventory for a typical summer day. Seasonal

adjustments were made to the inventory and the

inventory was scaled, based on population changes, for

the years 1992 to 1994. The use of this inventory

method to represent average annual PM-10

concentrations is acceptable. The use of this inventory

method to represent peak PM-10 days is less reliable

because emissions of PM-10 are likely to be higher

than the seasonal average on peak days; however, this

is currently the best available inventory for Imperial

County.

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4) Modeling Results

Full year model runs were performed for 1992, 1993,

and 1994. The maximum predicted concentration of

the annual standard at a monitoring site was 40.5

pg/m*, 42.8 pg/m?, and 41.6 pg/m® for the years 1992,

1993 and 1994, measured at the Calexico-Grant Street

monitoring site. See Table A below.

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Footnotes

fnl “State Implementation Plans for Serious PM-10

Nonattainment Areas, and Attainment Date Waivers

for PM-10 Nonattainment Areas Generally; Addendum

to the General Preamble for the Implementation of

Title I of the Clean Air Act Amendments of 1990,” 59

FR 41998, August 16, 1994.

fn2 There are currently seven PM-10 monitoring sites

in Imperial County. The Calexico-East monitor was

initiated in 1996. The data from this monitor are

currently being reviewed by EPA and the California

Air Resources Board (CARB) due to siting

deficiencies based on federal monitoring guidelines in

40 CFR Part 58, Appendix E.

fn3 A windrose is a diagram showing the percentage-of

time that wind blows from each compass direction for

various ranges of wind speeds.

-fn4 The Imperial Valley/Mexicali Cross Border PM-10

Transport Study (Final Report, January 30, 1997,

Prepared for EPA Region IX by Desert Research

Institute) also provided an analysis of transport for

three of the days which exceeded the PM-10 standard.

The report concluded that January 19, 1993 was

determined to be associated with stagnation conditions,

so that little transport took place. January 25, 1993 was

determined to be not affected by transport. August 23,

1993 appeared to be dominated by transport.

fn5 Modeled annual average concentrations at all of

the sites are below 43 pg/m’ for each of the 3 years,

64a

assuming only emissions from the United States side

of the border.

fn6 The Southern California Ozone Study (SCOS) was

a large-scale field measurement program carried out in

southern California during the summer of 1997 to

collect sufficient gerometric data to allow data,

analysts and modelers to characterize and simulate

ozone formation and fate in the region. Several

agencies and others participated during the planning

and operational phases of the field study, including

GARB, EPA, local air districts, the US Navy, and the

marine industry.

fn7 Since the applicable attainment date for the CAA

section 179B(d) demonstration is December 31, 1994,

post 1994 years were not addressed in the State’s

179B(d) demonstration.

[Attachments 1 and 2 not reproduced here. The

petition contains the relevant Excerpt of Record

citations to this material.]

HS he Se

ROE Bree NRC aN: ERO

65a

[Federal Register: October 19, 2001

(Volume 66, Number 203, Pages 53106-53112)

ENVIRONMENTAL PROTECTION AGENCY

40 CFR PART 81

[CA058-FOA; FRL-7087-1]

Clean Air Act Finding of Attainment; California-

Imperial Valley Planning Area; Particulate Matter of

10 Microns or Less (PM-10)

AGENCY: Environmental Protection Agency (EPA).

ACTION: Final rule.

SUMMARY: EPA is taking final action to find that the

State of California has established to EPA’s satisfaction

that the Imperial Valley Planning Area (Imperial

County), a PM-10 moderate nonattainment area, would

have attained the national ambient air quality tandards

(NAAQS) for particulate matter of ten microns or less

(PM-10) by the applicable Clean Air Act (CAA or the

Act) attainment date, December 31, 1994, but for

emissions emanating from outside the United States,

1.e., Mexico. As a result of this final action, Imperial

County will not be subject to a finding of failure to

attain and reclassification to serious at this time and

will remain a moderate PM-10 nonattainment area.

EFFECTIVE DATE: This action is effective on

November 19, 2001.

66a

ADDRESSES: You can, inspect copies of the

administrative record for this action at EPA’s Region 9

office during normal _ business hours. U.S.

Environmental Protection Agency, Region 9, Air

Division, Planning Office (AIR-2), 75 -Hawthorne

Street, San Francisco, California 94105.

Electronic Availability: This document is also available

as an electronic file on EPA’s Region 9 Web Page at

http://www.epa.gov/region09/air.

FOR FURTHER INFORMATION CONTACT: Doris

Lo, U.S. Environmental Protection Agency, Region 9,

Air Division, Planning Office (AIR-2), 75 Hawthorne

Street, San Francisco, California 94105, (415) 744-1287,

lo.doris@epa.gov.

SUPPLEMENTARY INFORMATION:

I. Background

Imperial County is a moderate PM-10 nonattainment

area located on the California border with Mexico, with

a December 31, 1994 attainment deadline. Under CAA

section 188(b)(2)(A), moderate PM-10 nonattainment

areas must be reclassified as serious by operation of law

after the statutory attainment date if the

Administrator finds that the area has failed to attain

the NAAQS. However, CAA section 179(B)(d) provides

that any area that establishes to the satisfaction of

EPA that it would have attained the PM-10 NAAQS by

the applicable attainment date but for emissions

emanating from outside the United States shall not be

subject to the provisions of CAA section 182(b).

67a

Imperial County and the California Air Resources

Board submitted evidence that the County would have

attained the PM-10 NAAQS but for transport from

Mexico. The primary information prepared by the

Imperial County Air Pollution Control District

(ICAPCD) is “Imperial County PM-10 Attainment

Demonstration” (hereafter referred to as the “179B(d)

Demonstration”) which was transmitted to EPA by the

California Air Resources Board (CARB) on July 18,

2001 letter from Michael P. Kenny, Executive Officer,

CARB, to Ms. Laura Yoshii, Acting Regional

Administrator, EPA Region 9).

Pursuant to CAA section 188(b)(2)(B) of the Act, EPA

must publish a notice in the Federal Register

identifying those areas that failed to attain the

standard and reclassifying the areas to serious. On

August 6, 2001, EPA issued two alternative proposals:

(1) To find that the State of California had established

to EPA’s satisfaction that Imperial County, a PM-10

moderate nonattainment area, would have attained the

NAAQS PM-10 by the applicable Clean Air Act

attainment date, December 31, 1994, but for emissions

emanating from outside the United States, i.e., Mexico.

(2) Alternatively, to find that Imperial County did not

attain the PM-10 NAAQS by its CAA mandated

attainment date. This proposed finding was based on

monitored air quality data for the PM-10 NAAQS

during the years 1992-1994. A final action would result

in a reclassification to serious PM-10 nonattainment for

Imperial County.

68a

These proposed alternative actions were published in a

Federal Register notice (66 FR 42187) on August 10,

2001 (proposed rule or notice of proposed rulemaking,

NPR). The 30-day public comment period ended on

September 10, 2001. EPA requested public comments

on both proposals and received ten comment letters

from the following:

Sierra Club/EarthJustice Legal Defense Fund (David

S. Baron, Attorney)

Imperial County Air Pollution Control District

(Stephen L. Birdsall, Air Pollution Control Officer)

Congressman Duncan Hunter, U.S. House of

Representatives, Washington, D.C. 20515-0552

Imperial Valley Vegetable Growers Association

(Lauren S. Grizzle, Executive Director)

Imperial County Farm Bureau (Lauren S. Grizzle,

Executive Director)

California Farm Bureau Federation (Cynthia L. Cory,

Director, Environmental Affairs)

Mar Vista Farms, Inc. (Michael B. Cox, President)

Nisei Farmers League (Manuel Cunha, Jr., President)

California Cotton Ginners and Growers Association-

(Roger A. Isom, Vice President & Director of Technical

Services)

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69a

Granite Construction Company (Jeff Mercer, Area

manager)

All of the commenters supported EPA’s proposed

finding of attainment pursuant to section 179B(d) of the

CAA, except for the Sierra Club/EarthJustice Legal

Defense Fund (Sierra Club).

While the Sierra Club raises some important issues,

EPA was aware of these issues prior to the proposed

rulemaking and has not been convinced by Sierra Club

that the State’s 179B(d) demonstration is inadequate

and that the finding of nonattainment and

reclassification to serious should be finalized. Thus,

EPA is finalizing its action to find that the State of

California has established that Imperial County would

have attained the NAAQS for PM-10 by the applicable

CAA attainment date, December 31, 1994, but for

emissions emanating from Mexico. Today’s rulemaking

provides EPA’s responses to public comments and

finalizes EPA’s proposed action.

II. Public Comments and EPA Responses

A. Sierra Club/EarthJustice Legal Defense Fund

(David S. Baron, Attorney)

Comments were submitted by the EarthJustice Legal

Defense Fund on behalf of the Sierra Club. In general,

the Sierra Club opposes our proposed finding of

attainment and asserts that the 179B(d) demonstration

does not adequately demonstrate attainment but for

the emissions emananting from Mexico. The Sierra

Club believes we must finalize our proposed finding of

70a

nonattainment and reclassification to serious PM-10

nonattainment for Imperial County.

1. CAA Requires Modeling

The Sierra Club’s first group of coniments address the

need for a modeling demonstration. The Sierra Club

asserts that air quality modeling is a requirement

under CAA Section 179B(d) and that in order to qualify

for a 179B(d) waiver, the state must make a showing

that is the equivalent of an attainment demonstration

which the Act and EPA’s own regulations and

guidelines require to be based on air quality modeling.

The Sierra Club then discusses how the State’s air

quality modeling does not adequately demonstrate

attainment of the 24-hour and annual PM-10 NAAQS

due to deficiencies with the modeling inventory and

modeling assumptions which are summarized in EPA’s

responses below.

EPA’s response: EPA disagrees with the Sierra Club

that a CAA Section 179(B)(d) waiver must be based on

air quality modeling. CAA section 179B(d) does not

require air quality modeling for PM-10 nonattainment

areas at international borders, and EPA’s guidance

relating to serious PM-10 nonattainment areas suggests

modeling as one of five methods that may be used to

determine attainment but for international

transport.fnl In issuing guidance on CAA section

179(B), EPA considered it appropriate to grant states

more flexibility in making the “but-for” attainment

determination for border areas

This text is long and has been trimmed here. Open the source document for the complete record.

This is a copy of a public record, reproduced as it was published. It is not legal advice, and it may not be the version a court would rely on. Check the official source before you cite it.