UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

REGION 6 

MULTIMEDIA PLANNING AND PERMITTING DIVISION 

1445 ROSS AVENUE, SUITE 1200 

DALLAS, TX 75202-2733 

 DATE: April 14, 2010 

SUBJECT: Technical Review of the Part 99 (Conformity to the State Implementation Plan of 

Transportation Plans, Programs, and Projects) Revisions Submitted by the State of 

New Mexico in November of 2006, June of 2007, and May of 2009. 

 FROM: Jeff Riley 

 Air Planning Section, 6PD-L 

TO: Files 

THROUGH: Guy Donaldson, Chief 

 Air Planning Section, 6PD-L 

Background

On November 2, 2006, the State of New Mexico submitted revisions to the New Mexico 

Administrative Code (NMAC) 20.2.99 to ensure consistency with amendments to the federal 

Transportation Conformity Rule. On June 27, 2007, and May 13, 2009, the state submitted 

further revisions to NMAC 20.2.99 for consistency with subsequent federal rule revisions. 

These revisions are discussed in detail below. 

The most recent approval by EPA of transportation conformity regulations for the State of New 

Mexico occurred on March 20, 2000 (65 FR 14877). This approval was a partial approval, with 

no action taken on sections 109.C.1, 114, 128.C-F, 137.E, 139.A.2, 140.A.1, and 147.B. The 

regulations submitted by the State were based on the transportation conformity rule promulgated 

on August 15, 1997. However, on March 2, 1999, the United States Court of Appeals for the 

District of Columbia Circuit issued its opinion in Environmental Defense Fund v. Environmental 

Protection Agency, 167 F.3d 641 (D.C. Cir. 1999). The Court granted the environmental group’s 

petition for review and ruled that 40 CFR 93.102(c)(1), 40 CFR 93.121(a)(1), and 40 CFR 

93.124(b) are unlawful, and remanded 40 CFR 93.118(e) and 40 CFR 93.120(a)(2) to EPA for 

revision to harmonize these provisions with the requirements of the Act for an affirmative 

determination the federal actions will not cause or increase violations or delay attainment. 

Since the States were required to submit transportation conformity SIPs not later than August 15, 

1998, and include those provisions in verbatim form, the State’s SIP revision included all of 

those sections which the Court ruled unlawful or remanded for consistency with the Act. EPA 

revised the Federal Rule on August 6, 2002 (67 FR 50808) and July 1, 2004 (69 FR 40004) in 

response to the Court decision, and the State of New Mexico’s November 2, 2006 submittal was 

intended to reflect these revisions and address the sections in question. 
- 2 - 

Analysis of the State’s Submittals

The following tables provide a comparison of revisions made to NMAC 20.2.99 and the 

corresponding sections in 40 CFR Part 93. An explanation of each revision is also provided. 

Table 1: November 2, 2006, Submittal 

TYPE OF AREA ISSUE ADDRESSED IN FINAL 

RULE 

PART 93 

FEDERAL 

REGULATORY 

SECTION 

PART 99 NEW 

MEXICO 

REGULATORY 

SECTION 

8-Hour Ozone 

National Ambient 

Air 

Quality Standard

Conformity Grace Period- This one-year 

conformity grace period is provided by 

Clean Air Act section 176(c)(6) and Sec. 

93.102(d) of the conformity regulation. 

Sec. 102(d) Sec. 109(D) 

Baseline Year Test - Adds the following 

tests to the conformity rule for 8-hour 

ozone nonattainment areas: 

 The "less-than-2002 emissions" test, 

and 

 The "no-greater-than-2002 

emissions" test. Under these interim 

emissions tests, conformity would be 

demonstrated if the emissions from the 

proposed transportation system are either 

less than or no greater than 2002 motor 

vehicle emissions in a given area.

Sec. 119(b) Sec. 138(B) 

Build, No-Build Test (Lower classifications) - 

The federal rule is amended to create the "buildno-greater-than-no-build" test, where 

conformity is demonstrated if emissions from 

the proposed transportation system ("build" 

or "action" scenario) are less than or equal to 

emissions from the existing transportation 

system ("no-build" or "baseline" scenario). 

The build-no-greater-than-no-build test is 

available to the following subset of new and 

existing areas: 

 8-hour ozone areas of marginal 

classification, and 

 8-hour ozone areas designated 

nonattainment under subpart 1 of part D 

of title 1 of the Clean Air Act ("subpart 

1 areas")

Sec. 119(b)(2); 

Sec. 119(g)(2) 

Sec. 138(B)(2); 

Sec. 138(G)(2)

Regional Conformity Tests Moderate and 

Above Classifications (Higher Classifications) - 

Ozone areas of higher nonattainment 

classifications must meet both the build-lessthan-no-build and 

less-than-baseline year tests to demonstrate 

conformity in the period before SIP budgets are 

available. This provision will affect moderate 

and above 1-hour and 8-hour ozone areas. This 

requirement is identical to the requirement of 

the existing conformity rule for these areas, and 

Sec. 119(b)(1) Sec. 138(B)(1) 
- 3 - 

was the first of three options proposed for 

regional emissions analyses before adequate or 

approved SIP budgets are established.

Regional Conformity Tests (Areas Without 1-

hour Ozone Budget) - These 8-hour ozone areas 

either were never designated nonattainment 

under the 1-hour ozone standard or were 1-hour 

ozone nonattainment areas that never submitted 

a control strategy SIP or maintenance plan with 

approved or adequate budgets. A regional 

emissions analysis is the part of a conformity 

determination that assesses whether the 

emissions produced by transportation activities 

are consistent with state, local, and federal air 

quality goals.

Sec. 109(d) Sec. 128(D) 

Regional Conformity Tests (Areas With 

1-hour Ozone Budget - This section covers how 

regional emissions analyses must be done in 8-

hour ozone areas with an existing 1-hour ozone 

SIP that covers either part or all of the 8-hour 

ozone nonattainment area. The regulatory text 

in Sec. 128 (e) of Part 99 provides a general 

overview of when the budget test and interim 

emissions tests apply in 8-hour ozone 

nonattainment areas with adequate or approved 

1-hour ozone SIP budgets. 

Sec. 109(e) Sec. 128(E) 

Definitions - Clarify the conformity rule's 

definitions for "control strategy implementation 

plan revision," "milestone," ''donut areas," 

"isolated rural nonattainment and maintenance 

areas," 1-hour nonattainment area, and 8-hour 

nonattainment area in Sec. 7 of Part 99. The 

clarifications to these definitions do not impose 

any new requirements on nonattainment and 

maintenance areas; these rule revisions simply 

clanfy EPA's original intent and current 

implementation of the existing conformity rule.

Sec. 101 Sec. 7 

Areas With Insignificant Motor Vehicle 

Emissions - This section applies to 

nonattainment and maintenance areas where 

EPA fmds that the SIP'S motor vehicle 

emissions for a pollutant or precursor for a 

given standard are an insignificant contributor to 

an area's regional air quality problem. This 

provision waives the regional emissions analysis 

for an insignificant pollutant or precursor in 

these areas upon the effective date of EPA's 

adequacy finding or approval of such a SIP. 

Sec. 128(K) also establishes the minimum 

criteria that are necessary to demonstrate that 

motor vehicle emissions are insignificant.

Sec. 109(k); 

Sec.l2l(c) 

Sec. 128(K); 

Sec. 140(C) 

Transportation plan and modeling requirements 

(Higher Classifications) - Provides a two-year 

grace period in Sec. 143 of Part 99 before the 

more advanced transportation modeling 

requirements in Sec. 142 of Part 99 are required 

in the following types of nonattainment areas 

or portions of such areas that are not already 

required to meet these provisions: 

 Ozone areas that have an urbanized 

area population over 200,000 and are 

reclassified to a serious or higher classification 

Sec. 106(b); 

Sec. 122(c) 

Sec. 125(B); 

Sec. 143
- 4 - 

(e.g., such a moderate ozone area that is 

reclassified to serious); 

 Serious and above ozone areas in which the 

urbanized area population increases to over 

200,000; and 

 Newly designated ozone nonattainment 

areas that are classified as 

serious or above in which the urbanized 

area populations over 200,000. 

These revisions expand the types of areas 

covered by the rule's grace period for 

transportation plan content requirements. 

 Ozone areas that have an urbanized 

area population over 200,000 that are 

reclassified to a serious or higher classification 

(e.g., such a moderate ozone area that is 

reclassified to serious), 

 Serious and above ozone areas in which the 

urbanized area population increases to over 

200,000; and 

 Newly designated ozone nonattainment 

areas that are classified as serious or above in 

which the urbanized area population is over 

200,000. 

Clarifying that both Sec. Sec. 125(B) of Part 99 

and 93.143 of Part 99 that the two-year grace 

periods begins upon either the: 

 Effective date of EPA's action that 

reclassifies an ozone area with an urbanized 

area population over 200,000, to a serious or 

higher classification, 

 Official notice by the Census Bureau that 

the urbanized area population is over 200,000, 

or 

 Effective date of EPA’s action that initially 

designates an area as a serious or above ozone 

nonattainment area. 

Non-Federal Projects (For Isolated Rural 

Areas Only) - This is a minor clarification to 

Sec. 140(B)(1) of Part 99 that addresses the 

conformity requirements for non-federal 

projects in isolated rural nonattainment and 

maintenance areas. Specifically, the final rule 

requires a regionally significant non-federal 

project to be included in the regional emissions 

analysis of the most recent conformity 

determination "that reflects" the portion of the 

statewide transportation plan and statewide 

transportation improvement program (STP) 

which includes projects planned for the isolated 

rural nonattainment or maintenance area before 

the projects can be approved.

Sec. 121(b)(l) Sec. 140(B)(1) 

PM2.5 National 

Ambient Air Quality 

Standard 

Applicability - This revision includes PM2.5 as 

a criteria pollutant that is regulated under Part 

99 for transportation conformity purposes

Sec. 102(B)(1) Sec. 2(B) 

Conformity Grace Period - Clean Air Act 

section 176(c)(6) and Sec. 109(D) of 

Part 99 of the conformity regulation 

provide this one-year conformity grace 

period. This final rule adds PM2.5 to Sec. 

Sec. 102(d) Sec. 109(D) 
- 5 - 

109(D) of the conformity rule even 

though the grace period is already 

available to all newly designated 

nonattainment areas as a matter of law.

Baseline Year Test - Adds the following tests to 

the conformity rule for PM2.5 nonattainment 

areas: 

 The "less-than-2002 emissions" test, and 

 The "no-greater-than-2002 emissions" test. 

Under these interim emissions tests, 

conformity would be demonstrated if the 

emissions from the proposed 

transportation system are either less than 

or no greater than 2002 motor vehicle 

emissions in a given area.

Sec. 119(b) Sec. 138(B) 

Build/No-Build Test (Lower 

classifications) - As with the 8-hour 

ozone standard, EPA is revising the 

build/no-build test for certain existing 

and new nonattaininent areas. 

Specifically, the final rule amends Sec. 

138 to create the "build-no-greater-than-nobuild" test, where conformity is 

demonstrated if emissions from the 

proposed transportation system ("build" 

or "action" scenario) are less than or - 

equal to emissions from the existing 

transportation system ("no-build" or 

"baseline" scenario. The build-no-greaterthan-no-build test is available to 

all PM2.5 areas.

Sec. 119(e); 

Sec. 119(g)(2) 

Sec. 138(E); 

Sec. 138(G)(2) 

Regional Conformity Tests in PM2.5 Areas - 

EPA requires that the budget test be used to 

complete a regional emissions analysis once a 

PM2.5 SIP is submitted with budget(s) that EPA 

has found adequate or approved. PM2.5 

nonattainrnent areas must meet one of the 

following interim emissions tests for conformity 

determinations conducted before adequate or 

approved PM2.5 SIP budgets are established: 

 The build-no-greater-than-no-build test, or 

 The no-greater-than-2002 emissions test 

Sec. 109(i) Sec. 128(I) 

Re-entrained Road Dust in PM2.5 Regional 

Emissions Analyses – re-entrained road dust 

will only be included in regional emissions 

analyses if the EPA Regional Administrator or 

state air quality agency determines that reentrained road dust is a significant contributor to 

the PM2.5 regional air quality problem. In 

other words, PM2.5 areas can presume that reentrained road dust is not a significant 

contributor and not include road dust in PM2.5 

transportation conformity analyses prior 

to the SIP, unless EPA or the state finds road 

dust significant. Re-entrained road dust is 

granular material released into the atmosphere 

as a result of motor vehicle activity on paved 

and unpaved roads. 

Sec. 102(b)(3); 

Sec. 119(f) 

Sec. 2(D); 

Sec. 138(F) 

Construction-Related Fugitive Dust in PM2.5 

Regional Emissions Analyses - Constructionrelated fugitive dust from highway or transit 

projects are included in regional emissions 

Sec. 122(f) Sec. 146 
- 6 - 

analyses for PM2.5 nonattainment and 

maintenance areas only if the SIP identifies 

construction dust as a significant contributor to 

the regional air quality problem. ConstructionreIated fugitive dust is granular material 

released into the atmosphere during 

construction. Construction-related dust 

emissions would not be included in any PM2.5 

conformity analyses before adequate or 

approved PM2.5 SIP budgets are established.

Compliance With PM2.5 SIP Control Measures 

- The rule requires that Federal Highway 

Administration (FHWA) and Federal 

Transportation Administration (FTA) projects in 

PM2.5 nonattainment and maintenance areas 

comply with the applicable SIP'S PM2.5 control 

measures, when such measures exist. Under the 

final rule, FHWA and FTA would assure 

implementation of a required control or 

mitigation measure by obtaining enforceable 

written commitments from the project sponsor 

and/or operator prior to making a project-level 

conformity determination. This requirement 

would be satisfied if the project-level 

conformity determination contains a written 

commitment from the project sponsor to include 

the control measures in the final plans, 

specifications and estimates for the project.

Sec. 117 Sec. 136 

Definitions - Clarify the conformity rule's 

definitions for "control strategy implementation 

plan revision," "milestone," "donut areas," 

"isolated rural nonattainment and maintenance 

areas," 1-hour nonattainment area, and 8-hour 

nonattainment area in Sec. 7 of Part 99. The 

clarifications to these definitions do not impose 

any new requirements on nonattainment and 

maintenance areas; these rule revisions simply 

clanfy EPA's original intent and current 

implementation of the existing conformity rule.

Sec. 101 Sec. 7 

Areas With Insignificant Motor Vehicle 

Emissions - This section applies to 

nonattainment and maintenance areas where 

EPA finds that the SIP'S motor vehicle 

emissions for a pollutant or precursor for a 

given standard are an insignificant contributor to 

an area's regional air quality problem. This 

provision waives the regional emissions analysis 

for an insignificant pollutant or precursor in 

these areas upon the effective date of EPA's 

adequacy finding or approval of such a SIP. 

Sec. 128(K) of Part 99 also establishes the 

minimum criteria that are necessary to 

demonstrate that motor vehicle emissions are 

insignificant. 

Sec. 109(k); 

Sec. 121(c) 

Sec. 128(K); 

Sec. 140(C) 

Non-Federal Projects (For Isolated Rural Areas 

Only) - This is a minor clarification to Sec. 

140(B)(1) of Part 99 that addresses the 

conformity requirements for non-federal 

projects in isolated rural nonattainment and 

maintenance areas. Specifically, the final rule 

requires a regionally significant non-federal 

Sec. 121(b)(1) Sec. 140(B)(1) 
- 7 - 

project to be included in the regional emissions 

analysis of the most recent conformity 

determination "that reflects" the portion of the 

statewide transportation plan and statewide 

transportation improvement program (STIP) 

which includes projects planned for the isolated 

rural nonattainment or maintenance area before 

the projects can be approved.

1-Hour Ozone 

National Ambient 

Air Quality Standard 

Build/ No-Build Test (Lower classifications) - 

The federal rule is amended to create the "buildno-greater-than-no-build" test, where 

conformity is demonstrated if emissions from 

the proposed transportation system ("build" 

or "action" scenario) are less than or equal to 

emissions from the existing transportation 

system ("no-build" or "baseline" scenario). 

The build-no-greater-than-no-build test is 

available to the following subset of new and 

existing areas: 

 1-hour ozone areas of marginal and 

below classifications.

Sec. 119(b)(2); 

Sec. 119(g)(2) 

Sec. 138(B)(2); 

Sec. 138(G)(2) 

Regional Conformity Tests Moderate and 

Above Classifications (Higher classifications) - 

Ozone areas of higher nonattainment 

classifications must meet both the build-lessthan-no-build and 

less-than-baseline year tests to demonstrate 

conformity in the period before SIP budgets are 

available. This provision will affect moderate 

and above 1-hour and 8-hour ozone areas. This 

requirement is identical to the requirement of 

the existing conformity rule for these areas, and 

was the first of three options proposed for 

regional emissions analyses before adequate or 

approved SIP budgets are established.

Sec. 119(b)(1) Sec. 138(B)(1) 

Definitions - Clarify the conformity rule's 

definitions for "control strategy implementation 

plan revision","milestone," "donut areas," 

"isolated rural nonattainment and maintenance 

areas," 1-hour nonattainment area, and 8-hour 

nonattainment area in Sec. 7 of Part 99. The 

clarifications to these definitions do not impose 

any new requirements on nonattainment and 

maintenance areas; these rule revisions simply 

clarify EPA's original intent and current 

implementation of the existing conformity rule.

Sec. 101 Sec. 7 

Areas With Insignificant Motor Vehicle 

Emissions - This section applies to 

nonattainment and maintenance areas where 

EPA finds that the SIP'S motor vehicle 

emissions for a pollutant or precursor for a 

given standard are an insignificant contributor to 

an area's regional air quality problem. This 

provision waives the regional emissions analysis 

for an insignificant pollutant or precursor in 

these areas upon the effective date of EPA's 

adequacy finding or approval of such a SIP. 

Sec. 128(K) also establishes the minimum 

criteria that are necessary to demonstrate that 

motor 

vehicle emissions are insignificant.

Sec. 109(k); 

Sec. 121(c) 

Sec. 128(K); 

Sec. 140(C) 

Limited Maintenance Plans – These revisions Sec. 101; Sec. 7(Z); 
- 8 - 

make the conformity rule consistent with EPA's 

existing limited maintenance plan policies for 

the 1-hour ozone standard. The revisions allows 

for any future limited maintenance plan policies 

for other standards to be considered in the 

conformity process. In general, a limited 

maintenance plan policy allows a nonattainment 

area with air quality that is significantly below a 

standard to request redesignation through a 

more streamlined maintenance plan. 

Sec. 109(j); 

Sec. 121(c) 

Sec. 128(J); 

Sec. 140(C) 

Transportation plan and modeling requirements 

(Higher classifications) - Provides a two-year 

grace period in Sec. 143 of Part 99 before the 

more advanced transportation modeling 

requirements in Sec. 142 of Part 99 are required 

in the following types of nonattainment areas 

or portions of such areas that are not already 

required to meet these provisions: 

 Ozone areas that have an urbanized area 

population over 200,000 and are reclassified to a 

serious or higher classification (e.g., such a 

moderate ozone area that is reclassified to 

serious); 

 Serious and above ozone areas in which the 

urbanized area population increases to over 

200,000; and 

 Newly designated ozone nonattainment 

areas that are classified as serious or above in 

which the urbanized area populations over 

200,000. 

These revisions expand the types of areas 

covered by the rule's grace period for 

transportation plan content requirements. 

 Ozone areas that have an urbanized area 

population over 200,000 that are reclassified to 

a serious or higher classification (e.g., such a 

moderate ozone area that is reclassified to 

serious), 

 Serious and above ozone areas in which the 

urbanized area population increases to over 

200,000; and 

 Newly designated ozone nonattainment 

areas that are classified as serious or above in 

which the urbanized area population is over 

200,000. 

Clarifying that both Sec. 125(B) of Part 99 and 

93.143 of Part 99 that the two-year grace 

periods begins upon either the: 

 Effective date of EPA's action that 

reclassifies an ozone area with an urbanized 

area population over 200,000, to a serious or 

higher classification, 

 Official notice by the Census Bureau that 

the urbanized area popuIation is over 200,000, 

or 

 Effective date of EPA's action that initially 

designates an area as a serious or above ozone 

nonattainment area.

Sec. 106(b); 

Sec. 122(c) 

Sec. 125(B); 

Sec. 143 

Non-Federal Projects (For Isolated Rural Areas 

Only) - This is a minor clarification to Sec. Sec. 121(b)(1) Sec. 140(B)(1) 
- 9 - 

140(B)(1) of Part 99 that addresses the 

conformity requirements for non-federal 

projects in isolated rural nonattainment and 

maintenance areas. Specifically, the final rule 

requires a regionally significant non-federal 

project to be included in the regional emissions 

analysis of the most recent conformity 

detexmination "that reflects" the portion of the 

statewide transportation plan and statewide 

transportation improvement program (STIP) 

which includes projects planned for the isolated 

rural nonattainment or maintenance area before 

the projects can be approved.

Clarification to Use of Approved Budgets in 

Conformity - A clarification to the November 5, 

2003 final rule, EPA proposed to clarify the 

requirements for each criteria pollutant and 

standard that the budget test must be satisfied as 

required by Sec. 137 of Part 99 for conformity 

determinations made on or after any one of the 

following: 

 The effective date of EPA's finding that a 

motor vehicle emissions budget in a submitted 

SIP is adequate, 

 The publication date of EPA's approval of 

such a budget in the Federal Register, or 

 The effective date of EPA's approval of 

such a budget in the Federal Register, if the 

approval is completed through direct final 

rulemaking. 

Under this final rule change, the budget would 

be used in any conformity determination 

conducted after the first time one of these three 

EPA actions occurs.

Sec. 109(c) Sec. 128(C) 

PM10 National 

Ambient Air Quality 

Standard 

Build No-Build Test (Lower classifications) - 

As with the PM 2.5 standard, EPA is revising 

the build/no-build test for certain existing and 

new nonattainment areas. Specifically, the final 

rule amends Sec. 138 to create the "build-nogreater-than-no-build" test, where conformity is 

demonstrated if emissions from the proposed 

transportation system ("build" or "action" 

scenario) are less than or equal to emissions 

from the existing transportation system ("nobuild" or "baseline" scenario. The build-nogreater-than-no-build test is available to all 

PM10 areas.

Sec. 199(d); 

Sec. 119(g)(2) 

Sec. 138(D); 

Sec. 138(G)(2) 

Clarification to Precursors – These revisions 

clarify the list of PM10 precursors in c. Sec. 

2(C)(3) and 138(f)(5) of Part 99. Under the 

revised Sec. 2(C)(3), only VOC and NOx are 

identified as PM10 precursors; i.e., PM10 

is deleted from the list of PM10 precursors in 

this paragraph. The revisions to Sec. 138(f)(5) 

provide consistency with other pollutants and 

precursors discussed in this paragraph. Neither 

of these rule changes wilI affect conformity 

determinations in PM10 nonattainment and 

maintenance areas.

Sec. 109(b)(2)(iii); 

Sec. 119(f)(5) 

Sec. 2(C)(3); 

Sec. 138(F)(5) 

Definitions - Clarify the conformity rule's 

definitions for "control strategy implementation 

Sec. 101 Sec. 7 
- 10 - 

plan revision," "milestone," "donut areas," 

"isolated rural nonattainment and maintenance 

areas," 1-hour nonattainment area, and 8-hour 

nonattainment area in Sec. 7 of Part 99. The 

clarifications to these definitions do not impose 

any new requirements on nonattainment and 

maintenance areas; these rule revisions simply 

clarify EPA's original intent and current 

implementation of the existing conformity rule. Areas With Insignificant Motor Vehicle 

Emissions - This section applies to 

nonattainment and maintenance areas where 

EPA finds that the SIP's motor vehicle 

emissions for a pollutant or precursor for a 

given standard are an insignificant contributor to 

an area's regional air quality problem. This 

provision waives the regional emissions analysis 

for an insignificant pollutant or precursor in 

these areas upon the effective date of EPA's 

adequacy finding or approval of such a SIP. 

Sec. 128(K) also establishes the minimum 

criteria that are necessary to demonstrate that 

motor vehicle emissions are insignificant.

Sec. 109(k); 

Sec. 121(c) 

Sec. 128(K); 

Sec. 140(C) 

Limited Maintenance Plans – These revisions 

make the conformity rule consistent with EPA's 

existing limited maintenance plan policies for 

the 1-hour ozone standard. The revisions allows 

for any future limited maintenance plan policies 

for other standards to be considered in the 

conformity process. In general, a limited 

maintenance plan policy allows a nonattainment 

area with air quality that is significantly below a 

standard to request redesignation through a 

more streamlined maintenance plan.

Sec. 101; 

Sec. 109(j); 

Sec. 121(c) 

Sec. 7(Z); 

Sec. 128(J); 

Sec. 140(C) 

Non-Federal Projects (For Isolated Rural 

Areas Only) - This is a minor clarification to 

Sec. 140(B)(1) of Part 99 that addresses the 

conformity requirements for non-federal 

projects in isolated rural nonattainment and 

maintenance areas. Specifically, the final rule 

requires a regionally significant non-federal 

project to be included in the regional emissions 

analysis of the most recent conformity 

determination "that reflects" the portion of the 

statewide transportation plan and statewide 

transportation improvement program (STP) 

which includes projects planned for the isolated 

rural nonattainment or maintenance area before 

the projects can be approved.

Sec. 121(b)(l) Sec. 140(B)(1) 

Clarification to Use of Approved Budgets in 

Conformity - A clarification to the November 5, 

2003 final rule, EPA proposed to clarify the 

requirements for each criteria pollutant and 

standard that the budget test must be satisfied as 

required by Sec. 137 for conformity 

determinations made on or after any one 

of the following: 

 The effective date of EPAts finding that a 

motor vehicle emissions budget in a submitted 

SIP is adequate, 

 The publication date of EPA’s approval of 

such a budget in the Federal Register, or 

Sec. 109(g) Sec. 128(G) 
- 11 - 

 The effective date of EPA1s approval of 

such a budget in the Federal Register, if the 

approval is completed through direct final 

rulemaking. 

Under this final rule change, the budget would 

be used in any conformity determination 

conducted after the first time one of these three 

EPA actions occurs.

CO National 

Ambient Air Quality 

Standard 

Build/No-Build Test (Lower classifications) - 

The federal rule is amended to create the "buildno-greater-than-no-build" test, where 

conformity is demonstrated if emissions from 

the proposed transportation system ("build" 

or "action" scenario) are less than or equal to 

emissions from the existing transportation 

system ("no-build" or "baseline" scenario). 

The build-no-greater-than-no-build test is 

available to the following subset of new and 

existing areas: 

 CO areas of moderate classification with 

design values less than 12.7 ppm, and 

 Not classified CO areas.

Sec. 119(c); 

Sec. 119(g)(2) 

Sec. 138(C); 

Sec. 138(G)(2) 

Regional Conformity Tests Moderate and 

Above Classifications (Higher Classifications) - 

CO areas of higher nonattainment classifications 

must meet both the build-less-than-no-build and 

less-than-baseline year tests to demonstrate 

conformity in the period before SIP budgets are 

available. This provision will affect moderate 

CO areas with design values greater than 12.7 

ppm, and serious CO areas. This requirement is 

identical to the requirement of the existing 

conformity rule for these areas, and was the first 

of three options proposed for regional emissions 

analyses before adequate or approved SIP 

budgets are established.

Sec. 119(c)l Sec. 138(C)1 

Definitions – Clarify the conformity rule's 

definitions for "control strategy implementation 

plan revision," "milestone," "donut areas," 

"isolated rural nonattainment and maintenance 

areas," 1-hour nonattainment area, and 8- 

hour nonattainment area in Sec. 7 of Part 

99. The clarifications to these defjnitions do not 

impose any new requirements on nonattainment 

and maintenance areas; these rule revisions 

simply clarify EPA's original intent and current 

implementation of the existing conformity rule. 

Sec. 101 Sec. 7 

Areas With Insignificant Motor Vehicle 

Emissions - This section applies to 

nonattainment and maintenance areas where 

EPA finds that the SIP's motor vehicle 

emissions for a pollutant or precursor for a 

given standard are an insignificant contributor to 

an area's regional air quality problem. This 

provision waives the regional emissions analysis 

for an insignificant pollutant or precursor in 

these areas upon the effective date of EPA's 

adequacy finding or approval of such a SIP. 

Sec. 128(K) of Part 99 also establishes the 

minimum criteria that are necessary to 

demonstrate that motor vehicle emissions are 

Sec. 109(k); 

Sec. 121(c) 

Sec. 128(K); 

Sec. 140(C) 
- 12 - 

insignificant.

Limited Maintenance Plans – These revisions 

make the conformity rule consistent with EPA's 

existing limited maintenance plan policies for 

the CO standard. The revisions allows for any 

future limited maintenance plan policies for 

other standards to be considered in the 

conformity process. In general, a limited 

maintenance plan policy allows a nonattainment 

area with air quality that is significantly below a 

standard to request redesignation through a 

more streamlined maintenance plan.

Sec. 101; 

Sec. 109(j); 

Sec. 121(c) 

Sec. 7(Z); 

Sec. 128(J); 

Sec. 140(C) 

Transportation plan and modeling requirements 

(Higher Classifications) - Provides a two-year 

grace period in Sec.143 of Part 99 before the 

more advanced transportation modeling 

requirements in Sec. 142 of Part 99 are required 

in the following types of nonattainment areas 

or portions of such areas that are not already 

required to meet these provisions: 

 CO areas that have an urbanized area 

population over 200,000 and are reclassified to a 

serious or higher classification (e.g., such a 

moderate CO area that is reclassified to serious); 

 Serious and above CO areas in which the 

urbanized area population increases to over 

200,000; and 

 Newly designated CO nonattainment areas 

that are classified as serious or above in which 

the urbanized area populations over 200,000. 

These revisions expand the types of areas 

covered by the rule's grace period for 

transportation plan content requirements. 

 Serious and above CO areas in which the 

urbanized area population increases to over 

200,000; and 

 Newly designated CO nonattainment areas 

that are classfied as serious or above in which 

the urbanized area population is over 200,000. 

Clarifying that both Sec. 125(B) and 93.143 of 

Part 99 that the two-year grace periods begins 

upon either the: 

 Effective date of EPA's action that 

reclassifies a CO area with an urbanized area 

population over 200,000, to a serious or higher 

classification, 

 Official notice by the Census Bureau that 

the urbanized area population is over 200,000, 

or 

 Effective date of EPA's action that initially 

designates an area as a serious or above CO 

nonattainment area. 

Sec. 106(b); 

Sec. 122(c) 

Sec. 125(B); 

Sec. 143 

Non-Federal Projects (For Isolated Rural Areas 

Only) - This is a minor clarification to Sec. 

140(B)(1) of Part 99 that addresses the 

conformity requirements for non-federal 

projects in isolated rural nonattainment and 

maintenance areas. Specifically, the final rule 

requires a regionally significant non-federal 

Sec. 121(b)(1) Sec. 140(B)(1) 
- 13 - 

project to be included in the regional emissions 

analysis of the most recent conformity 

determination "that reflects" the portion of the 

statewide transportation plan and statewide 

transportation improvement program (STIP) 

which includes projects planned for the isolated 

rural nonattainment or maintenance area before 

the projects can be approved.

Clarification to Use of Approved Budgets in 

Conformity - A clarification to the November 5, 

2003 final rule, EPA proposed to clarify the 

requirements for each criteria pollutant and 

standard that the budget test must be satisfied as 

required by Sec. 137 for conformity 

determinations made on or after any one of the 

following: 

 The effective date of EPA's finding that a 

motor vehicle emissions budget in a submitted 

SIP is adequate, 

 The publication date of EPA’s approval of 

such a budget in the Federal Register, or 

 The effective date of EPA's approval of 

such a budget in the Federal Register, if the 

approval is completed through direct fina1 

rulemaking. 

Under this final rule change, the budget 

would be used in any conformity 

determination conducted after the fxst 

time one of these three EPA actions 

occurs

Sec. 109(f) Sec. 128(f) 

NOx National 

Ambient Air Quality 

Standard 

Build/ No-Build Test (Lower classifications) - 

The federal rule is amended to create the "buildno-greater-than-no-build" test, where 

conformity is demonstrated if emissions from 

the proposed transportation system ("build" 

or "action" scenario) are less than or equal to 

emissions from the existing transportation 

system ("no-build" or "baseline" scenario). 

The build-no-greater-than-no-build test is 

available to the following all NO2 areas.

Sec. 119(d); 

Sec. 119(g)(2) 

Sec. 138(D); 

Sec. 138(G)(2) 

Definitions - Clarify the conformity rule's 

definitions for "control strategy implementation 

plan revision," "milestone," "donut areas," 

"isolated rural nonattainment and maintenance 

areas," 1 -hour nonattainment area, and 8-hour 

nonattainment area in Sec. 7 of Part 99. The 

clarifications to these definitions do not impose 

any new requirements on nonattainment and 

maintenance areas; these rule revisions simply 

clarify EPA's original intent and current 

implementation of the existing conformity rule.

Sec. 101 Sec. 7

Areas With Insignificant Motor Vehicle 

Emissions - This section applies to 

nonattainment and maintenance areas where 

EPA finds that the SIP's motor vehicle 

emissions for a pollutant or precursor for a 

given standard are an insignificant contributor to 

an area's regional air quality problem. This 

provision waives the regional emissions analysis 

for an insigruficant pollutant or precursor in 

these areas upon the effective date of EPA's 

Sec. 121(c) Sec. 140(C) 
- 14 - 

adequacy finding or approval of such a SIP. 

Sec. 128(K) also establishes the minimum 

criteria that are necessary to demonstrate that 

motor vehicle emissions are insignificant.

Non-Federal Projects (For Isolated Rural Areas 

Only) - This is a minor clarification to Sec. 

140(B)(1) of Part 99 that addresses the 

conformity requirements for non-federal 

projects in isolated rural nonattainment and 

maintenance areas. Specifically, the final rule 

requires a regionally significant non-federal 

project to be included in the regional emissions 

analysis of the most recent conformity 

determination "that reflects" the portion of the 

statewide transportation plan and statewide 

transportation improvement program (STIP) 

which includes projects planned for the isolated 

rural nonattainment or maintenance area before 

the projects can be approved.

Sec. 121(b)(l) Sec. 140(B)(1) 

Clarification to Use of Approved Budgets in 

Conformity – A clarification to the November 5, 

2003 final rule, EPA proposed to clarify the 

requirements for each criteria pollutant and 

standard that the budget test must be satisfied as 

required by Sec. 137 for conformity 

determinations made on or after any one of the 

following: 

 The effective date of EPA's finding that a 

motor vehicle emissions budget in a submitted 

SIP is adequate, 

 The publication date of EPA's approval of 

such a budget in the Federal Register, or 

 The effective date of EPA's approval of 

such a budget in the Federal Register, if the 

approval is completed through direct final 

rulemaking.

Under this final rule change, the budget would 

be used in any conformity determination 

conducted after the first time one of these three 

EPA actions occurs.

Sec. 109(h) Sec. 128(h) 

Miscellaneous 

Revisions 

Federal Projects - final rule modifies Sec. 

109(C) of the Part 99 so that no new federal 

approvals or funding commitments for nonexempt projects can occur during a 

transportation conformity lapse. A conformity 

lapse generally occurs if transportation plan and 

TIP conformity determinations are not made 

within specified time frames. During a 

conformity lapse no new conformity 

determinations for plans, TIPS, and FHWA or 

FTA non-exempt projects may be made. Under 

the new Sec. 109(C) provision, non-exempt 

transportation project phases can be 

implemented during a lapse if they have 

received all required FHWA or FTA approvals 

or funding commitments and have met 

associated confonnity requirements before the 

lapse. However, no new federal approvals or 

funding commitments for subsequent or new 

project phases can be made during the lapse.

Sec. 102(c) Sec. 109(C) 
- 15 - 

Determining Vehicle Emissions Budgets From 

Submitted SIPS Adequate – The final rule 

modified several provisions under Sec. 128 and 

137 of Part 99 to specify that EPA must 

affirmatively find submitted budgets adequate 

before they can be used in a conformity 

determination. The final rule also establishes 

the process by which EPA will review and make 

adequacy findings for submitted SIPs, as 

described in the June 30, 2003 proposal. 

Specifically, the final rule eliminates those 

provisions in Sec. 128 and 137(E) that required 

areas to use budgets from submitted SIPs 45 

days after submission unless EPA had 

found them inadequate. Instead, today's rule 

stipulates that before a budget from a SIP 

submission can be used in conformity, EPA 

must find it adequate using the criteria in Sec. 

137(E)(4).

Sec. 109; 

Sec. 118(e) 

Sec. 128; 

Sec. 137(E) 

General Description of the Vehicle Emissions 

Budgets Adequacy Process - The final rule adds 

a new provision, Sec. 137(F), to the conformity 

rule that provides the basic framework of the 

adequacy process. The new Sec. 137(F) 

generally reflects EPA's existing adequacy 

process as proposed in the June 30, 2003 

rulemaking and described in EPA's 1999 

adequacy guidance. The adequacy process 

consists of three basic steps: public notification 

of a SIP submission, a public comment period, 

and EPA's adequacy finding, including response 

to submitted comments.

Sec. 118(f) Sec. 137(F) 

Vehicle Emissions Budgets Adequacy Reviews 

Through the SIP Process – This revision 

finalizing procedures for conducting adequacy 

reviews and making adequacy findings through 

the SIP approval process in Sec. 137(F)(2).

Sec. 118(f)(2) Sec. 137(F)(2) 

Non-Federal Projects - A minor change 

amending Sec. 140(A) of the conformity rule so 

that regionally sigmficant nonfederal projects 

can no longer be advanced during a conformity 

lapse unless they have received all necessary 

state and local approvals prior to the lapse. Nonfederal projects are projects that are funded or 

approved by a recipient of federal funds 

designated under title 23 U.S.C. or the Federal 

Transit Laws, but that do not require any 

FHWA/FTA funding or approvals. Under this 

final rule, recipients of federal funds cannot 

adopt or approve a regionally significant, nonfederal project unless it is included in a 

currently conforming plan and TIP or is 

reflected in the regional emissions analysis 

supporting a currently conforming plan and TIP.

Sec. 121(a) Sec. 140(A) 

Safety Margins - Sec. 149(B) of the conformity 

rule that provided a narrowly targeted flexibility 

to areas with SIPs that had been submitted prior 

to the publication date of the original 

November 24, 1993 conformity rule was 

deleted. Under this provision, if an approved 

SIP submitted before November 24, 1993, had 

included a safety margin, but did not specify 

Sec. 124(b) Sec. 149(B) 
- 16 - 

how the safety margin was to be used, an area 

could submit a revision to the SIP and 

specifically allocate all or a portion of the safety 

margin to the SIP'S motor vehicle emissions 

budget(s). The 1997 rule allowed this SIP 

revision to become effective for conformity 

purposes before EPA had approved the revision. 

EPA is not aware of any nonattainment or 

maintenance areas that are currently affected by 

the elimination of this provision.

Streamlining the Frequency of Conformity 

Determinations – Several revisions to the 

frequency requirements listed in Sec. 113 of 

Part 99. Specifically, eliminating Sec. 

113(C)(4) that required an MPO and DOT to 

determine conformity of the TIP within six 

months of the date that DOT determined 

conformity of the transportation plan. 

Finalizing several rule revisions to streamline 

Sec. 115 of Part 99. In particular, eliminating 

Sec. 115(e)(l) that required all nonattainment 

and maintenance areas to determine conformity 

within 18 months of November 24, 1993 (i.e., 

the date that EPA originally promulgated the 

conformity rule, 58 FR 621 88). Sec. 115(A) is 

no longer relevant for any area. Finalizing two 

revisions to Sec. 115, which requires a 

conformity determination within 18-months of 

EPA's approval of a SIP. The first is specifying 

that an 18-month clock begins on the effective 

date of EPA's approval of the SIP. This 

clarification will resolve any ambiguity in the 

current rule as to when this 18-month clock 

begins. The second revision to Sec. 115(B) will 

require a conformity determination only when a 

conformity determination has not already been 

made using that same budget in the newly 

approved SIP.

Sec. 104(c)(4); 

Sec. 104(e) 

Sec. 113(D); 

Sec. 115 

Latest Planning Assumptions - Amending Sec. 

129(A) to change the point in the conformity 

process when the latest planning assumptions 

are determined. This revision will allow 

conformity determinations to be based on the 

latest planning assumptions that are available at 

the time the conformity analysis begins, rather 

than at the time of DOT's conformity 

determination for a transportation plan, TIP, or 

project.

Sec. 110(a) Sec. 129(A) 

Horizon Years for Hot-Spot Analyses - The 

revision clarifies Sec. 135 of the conformity rule 

so that project-level hotspot analyses in 

metropolitan nonattainrnent and maintenance 

areas must consider the full time frame of an 

area's transportation plan at the time the analysis 

is conducted. 

Sec. 116 Sec. 135 

Relying on a Previous Regional Emissions 

Analysis - finalizing three revisions to Sec. 147, 

which describes when an area can rely on a 

previous regional emissions analysis for a new 

conformity determination. First revision is to 

Sec. 147 so that MPOs can rely on a previous 

regional emissions analysis for minor 

Sec. 112(g) Sec. 147 
- 17 - 

transportation plan revisions. Second revision 

adds Sec. 147(C) to clarify that a conformity 

determination that relies on a previous analysis 

does not satisfy the three-year frequency 

requirement for plans and TIPs. Third revision 

adds Sec. 147(A)(4) and amends Sec. 147(B) to 

clarify that conformity determinations that rely 

on a previous regional emissions analysis must 

be based on all adequate and approved SIP 

budgets that apply at the time that DOT makes 

its conformity determination.

Budget Test Requirements for the Attainment 

Year – Revision clarifying how Sec. 137(B) and 

(D) should be implemented when a budget is 

established for a year prior to the attainment 

year (e.g., a reasonable further progress budget). 

Specifically, amending Sec. 137 (B) so that 

once an area has any control strategy SIP budget 

available for conformity purposes, conformity 

must be demonstrated using the "budget test" for 

the attainment year if the attainment year is 

within the time frame of the transportation plan.

Sec. 118(d) Sec. 137(D) 

Budget Test Requirements Once a Maintenance 

Plan Is Submitted - finalizing two minor 

changes to Sec. 137(B)(2) to clarify which 

budgets apply when an area has both control 

strategy SIP and maintenance plan budgets. 

First, EPA is clarifying Sec. 118(B)(2)(c) so 

that when a maintenance plan has been 

submitted, the budget test is also completed for 

a submitted adequate control strategy SIP 

budget that is established for any year within the 

time frame of the transportation plan. The 

second revision is adding Sec. 137(B)(2)(d) to 

clarify that the budget(s) established for the 

most recent prior year must be used for any 

analysis years that are selected before the last 

year of the maintenance plan to meet the 

requirements of Sec. 137(D)(2).

Sec. 118(b)(2)(iii); 

Sec. 118(b)(2)(iv) 

Sec. 137(B)(2)(c) ; 

Sec. 137(B)(2)(d) 

Exempt Projects - A minor revision to the list of 

exempt projects in Sec. 151 of Part 99. On 

December 21, 1999, DOT published a rule 

revision to its right-of-way regulation (64 FR 

71284) that changed the citation for emergency 

or hardship advance land acquisitions (revised 

citation: 23 CFR 710.503) -- activities that are 

currently exempt from the conformity process. 

As a result, Sec. 151 has been amended to make 

the conformity rule fully consistent with DOT's 

December 1999 rulemaking.

Sec. 126 Sec. 151 

Table 2: June 27, 2007, Submittal 

REVISION ISSUE ADDRESSED IN FINAL 

RULE 

PART 93 

FEDERAL 

REGULATORY 

SECTION 

PART 99 NEW 

MEXICO 

REGULATORY 

SECTION 

PM2.5 Precursors 

May 6, 2005 revisions

The scope of the regulation to include the 

following pollutants: 

 NOX in PM2.5 areas, unless both the EPA 

Sec. 102(b)(2)(ii) Sec. 2(c) 
- 18 - 

Regional Administrator and the director of the 

state air agency have made a finding that 

transportation related emissions of NOX within 

the nonattainment area are not a significant 

contributor to the PM2.5 nonattainment 

problem, and 

 VOC, SOX and/or NH3 in PM2.5 areas 

either if the EPA Regional Administrator or the 

director of the state air agency has made a 

finding that transportation-related emissions 

of any of these precursors within the 

nonattainment area are a significant contributor 

to the PM2.5 nonattainment problem.

The reference 49 CFR 7.95 to read 49 CFR 7.43. 

This is a technical correction which is the 

result of Federal Department of Transportations 

(DOT) July 16, 1998, final rule that changed the 

citation of the transportation planning fee 

schedule provision (63 FR 38331).

Sec. 105(e) Sec. 124(A) 

The criteria and procedures for interim 

emissions in areas that do not have motor 

vehicle emission budgets to include the 

following pollutants: 

 NOX in PM2.5 areas, unless both the EPA 

Regional Administrator and the director of the 

state air agency have made a finding that 

transportation related emissions of NOX within 

the nonattainment area are not a significant 

contributor to the PM2.5 nonattainment 

problem, and 

 VOC, SOX and/or NH3in PM2.5 areas 

either if the EPA Regional Administrator or the 

director of the state air agency has made a 

finding that transportation-related emissions 

of any of these precursors within the 

nonattainment area are a significant contributor 

to the PM2.5 nonattainment problem.

Sec. 119(f) Sec. 138(F) 

PM2.5 Hot Spot 

March 10, 2006 

revisions

The definition for Hot-spot analysis to include 

the pollutant PM2.5. Sec. 101 Sec. 6(V) 

The conformity criteria for general 

transportation plans, programs and projects to 

include the pollutant PM2.5 for hot-spot 

analyses.

Sec. 109(b) Sec. 128(B) 

The criteria and procedures for PM2.5 

nonattainment and maintenance areas to include 

the following paragraph: 

 Federal Highway Administration/Federal 

Transit Administration projects in PM2.5 

nonattainment or maintenance areas must satisfy 

the appropriate hot-spot test required by 

Subsection A of Section 20.2.99.135 NMAC 

(Criteria and Procedures – Localized CO, PM10, 

and PM2.5 Violations (HOT SPOTS).

Sec. 109(i) Sec.128(I) 

The criteria for limited maintenance plans to 

include the pollutant PM2.5 for hot-spot 

analyses.

Sec. 109(j) Sec. 128(J) 

The conformity criteria for areas with 

insignificant motor vehicle emissions to include 

the pollutant PM2.5 for hot-spot analyses.

Sec.109(k) Sec. 128(K) 

The conformity criteria for Isolated rural 

nonattainment and maintenance areas to include Sec. 109(l) Sec. 128(L) 
- 19 - 

the pollutant PM2.5 for hot-spot analyses.

The section heading to include the pollutant 

PM2.5 criteria and procedures: 

 Localized CO, PM10, and PM2.5 

Violations (Hot-spots).

Sec. 116 Sec. 135 

Include the pollutant PM2.5 for hotspot analysis. 

Establishes which transportation project will 

require a hot-spot analysis.

Sec. 116(a) Sec.135(A) 

Typographical error correction from last 

regulation revision. Changed Section reference 

20.2.99.146 to 20.2.99.148.

 Sec. 135(A) 

The section heading to include the pollutant 

PM2.5 

 Procedures for Determining Localized CO, 

PM10 and PM2.5 Concentrations (Hot-Spot 

Analysis). 

Sec. 123 Sec. 148 

The subsection heading to include the pollutant 

PM2.5. Sec. 123(b) Sec.148(B) 

Clarification of which transportation projects are 

required to perform a hot-spot analysis for 

PM10 or PM2.5.

Sec. 123(b)(1) Sec148(B)(1) 

Clarification of which transportation projects are 

required to perform a qualitative analysis. Sec. 123(b)(2) Sec. 148(B)(2) 

Changing the paragraph to allow the US DOT, 

in consultation with EPA, the flexibility to make 

categorical hot-spot findings to further 

streamline analysis requirements when modeling 

shows that additional analyses are not necessary 

to meet Clean Air Act requirements for a given 

project.

Sec. 123(b)(3) Sec. 148(B)(3) 

Including the pollutant PM2.5 for mitigation and 

control measures in hot-spot analyses. Sec. 123(c)(4) Sec. 148(C)(4) 

Including the pollutant PM2.5 for construction 

related hot-spot analyses. Sec. 123(c)(5) Sec. 148(C)(5) 

Including the pollutant PM2.5 for mitigation and 

control measures as identified as conditions of 

the National Environmental Policy Act process.

Sec. 125(a) Sec. 150(A) 

Including the pollutant PM2.5 under exempt 

projects for mass transit projects. Sec. 126(b)(1) Sec. 151(A)(2) 

Typographical error correction from last 

regulation revision. Changed Code of Federal 

Regulation reference 23 CFR 710.204d to 23 

CFR 710.503.

Sec. 151(A)(4)(d) 

Removal of the pollutant PM10 from the second 

sentence and inclusion of follow sentence: 

 The local effects of projects with respect to 

PM10 and PM2.5 concentrations must be 

considered and a hot-spot analysis performed 

prior to making a project-level conformity 

determination, if a project in Table 3 also meets 

the criteria of Paragraph (1) of Subsection B of 

Section 20.2.99.148 NMAC.

Sec. 127 Sec. 151(B) 

Table 3: May 13, 2009, Submittal 

REVISION ISSUE ADDRESSED IN FINAL 

RULE 

PART 93 

FEDERAL 

REGULATORY 

PART 99 NEW 

MEXICO 

REGULATORY 
- 20 - 

SECTION SECTION 

Revised the definitions for Metropolitan 

Planning Organization (MPO) 

 Make rule consistent with SAFETEA-LU 

Sec. 101 Sec. 7(AC); 

Revised the first sentence of the definition for 

Transportation Control Measure (TCM) to 

clarify that TCMs as defined for conformity 

purposes also include any TCMs that are 

incorporated into the SIP through this new TCM 

substitution and addition process. 

 Make rule consistent with SAFETEA-LU 

Sec. 101 Sec. 7(AU); 

Revised the definitions for Transportation 

Improvement Program (TIP). Sec. 101 Sec. 7(AV); 

Removed “sulfur oxides (SOX)” and added in 

its place “sulfur dioxide (SO2)” 

 To make rule consistent with EPA’s PM2.5 

Implementation Rule

Sec. 102(b)(2)(v); 

119(f)(10)

Sec. 2(C)(5); 

138(F)(10)

Removed “for 20 years from the date EPA 

approves the area’s request under section 107(d) 

of the CAA for redesignation to attainment” and 

adding in its place “through the last year of a 

maintenance area’s approved CAA section 

175A(b) maintenance plan”. 

 EPA revised this section to ensure that 

conformity would apply in maintenance areas 

through the entire 20 years of their approved 

Clean Air Act section 175A(b) maintenance 

plan, unless the applicable implementation plan 

specifies that conformity would continue to 

apply beyond the end of that maintenance plan.

Sec. 102(b)(4) Sec. 2(E) 

Revised to require that the MPO and DOT 

determine conformity of a transportation plan at 

least every four years. 

 Make rule consistent with SAFETEA-LU

Sec. 104(b) Sec. 112(B); 

112(C) 

Revised to require that the MPO and DOT 

determine conformity of a transportation 

improvement program (TIP) at least every four 

years. 

 Make rule consistent with SAFETEA-LU 

Sec. 104(c) Sec. 113 

Revised to require a new transportation plan and 

TIP conformity determination to be made after 

actions that establish a new motor vehicle 

emissions budget for conformity, also known as 

“triggers” 

 Make rule consistent with SAFETEA-LU

Sec. 104(e) Sec. 115 

New provision included to provide the 

allowances for projects to meet conformity 

requirements during the lapse grace period. 

 Make rule consistent with SAFETEA-LU

Sec. 104(f) Sec. 111(B) 

Changed “revision(s)” to “amendment(s)” 

 Make rule consistent with the revised 

planning definitions in DOT’s February 14, 

2007, final transportation planning regulations 

(72 FR 7224). 

Sec. 105(c) Sec. 122 

Removed the reference “23 CFR 450.316(b)” 

replacing it with “23 CFR 450.316(a)” 

 Make rule consistent with the revised 

planning definitions in DOT’s February 14, 

2009, final transportation planning regulations 

(72 FR 7224). 

Sec. 105(e) Sec. 124(A) 
- 21 - 

Section renamed as “Content of transportation 

plans and timeframe of conformity 

determination”; 

 Make rule consistent with SAFETEA-LU 

Sec. 106 Sec. 125 

Amended to update the horizon years that apply 

when an area shortens the conformity 

timeframe. 

 Make rule consistent with SAFETEA-LU 

Sec. 106(a) Sec. 125(A)(1) 

Include regulatory provisions to provide the 

rules for shortening the conformity timeframe 

 Make rule consistent with SAFETEA-LU 

Sec. 106(d) Sec. 125(D) 

Removed provision of the transportation 

conformity rule that was vacated by the U.S. 

Court of Appeals for the District of Columbia 

Circuit (Environmental Defense v. EPA, et al., 

D.C. Cir. No. 04-1291) 

 This provision allowed 8-hour ozone areas 

to use the interim emissions test(s) for 

conformity determinations instead of 1-hour 

ozone SIP budgets where the interim emissions 

test(s) was determined to be more appropriate to 

meet Clean Air Act requirements. The court 

vacated this provision and remanded it to EPA. 

Sec. 109(e) Sec. 128(E) 

Included language to ensure that hot-spot 

analyses in isolated rural areas examine a 

project’s air quality impact over the timeframe 

of the long-range statewide transportation plan. 

Sec. 109(l) Sec. 128(L) 

Requires that there be a currently conforming 

transportation plan and TIP at the time of project 

approval, except during the lapse grace period, 

when a non-exempt project must come from the 

most recent conforming transportation plan and 

TIP. 

 Make rule consistent with SAFETEA-LU 

Sec. 114 Sec. 133 

Requires that regionally significant non-Federal 

projects either come from the currently 

conforming transportation plan and TIP, or the 

regional emissions analysis that supports such a 

transportation plan and TIP, except during the 

lapse grace period. 

 Make rule consistent with SAFETEA-LU 

Sec. 121 Sec. 140(A)(1) 

Revised to allow DOT, in consultation with 

EPA, to make categorical hot-spot findings for 

appropriate cases in CO nonattainment and 

maintenance areas if appropriate modeling 

shows that a type of highway or transit project 

does not cause or contribute to a new or 

worsened local air quality violation of the CO 

standards. 

Sec. 123(a)(3) Sec. 148(A)(3) 

Revised to require PM2.5 or PM10 hot-spot 

analyses to be completed for “New highway 

projects that have a significant number of diesel 

vehicles, and expanded projects that have a 

significant increase in the number of diesel 

vehicles”. The prior language stated “New or 

expanded highway projects that have a 

significant number of or significant increase in 

diesel vehicles”. 

 Incorporated as a technical clarification to 

address some confusion since the promulgation 

of the March 10, 2006 conformity rule (71 FR 

12468). 

Sec. 123(b)(1) Sec. 148(B)(1) 
- 22 - 

Revised to update the following terms: 

“Hazard elimination program” is now “Projects 

that correct, improve, or eliminate a hazardous 

location or feature”; 

“Safety improvement program” is now 

“Highway Safety Improvement Program 

Implementation”; and 

“Pavement marking demonstration” is now 

“Pavement marking”. 

 EPA is updating these terms to make them 

consistent with the terms in 23 U.S.C. 148, 

which has been amended by SAFETEA-LU 

Sec. 126 Sec. 151(A)(1) 

Table 4 provides a summary of all specific sections that were revised by the State of New 

Mexico in each submittal. EPA is approving entire sections as submitted by New Mexico, since 

the submittals include entire sections containing any revisions being made. Where sections were 

repeated in subsequent revisions, the more recent revisions are taken to supersede the previous 

revisions, since the more recent language captures the previous revisions. Table 5 represents the 

sections that EPA will approve with this action, sorted by date of submittal. 

Table 4 – Revisions to NMAC 20.2.99 

(by submittal date) 

NMAC 20.2.99 Section Submittal Date to EPA 

2(B), 2(C)(3), 2(C)(3)(a), 2(C)(3)(b), 2(D), 2(E), 

7(A)-(BA), 109(A)(1)(a)-(b), 109(C), 109(D), 

112(A)-(C), 113(A)-(C), 114(A)-(C), 115, 115(A)-

(C), 116(B), 116(C), 116(C)(1)(c), 116(C)(2)(a), 

116(D)(c)-(d), 117(B)(6), 117(C), 117(C)(5), 

118(B), 118(C), 120(A)-(D), 120(E)(2), 120(F), 

120(H)-(J), 120(L)-(M), 121(A)-(C), 121(D)(1)-(3), 

122, 123(B)-(D), 125(B), 125(B)(1)-(3), 128(B), 

128(B)(2)(b), 128(B)(3)(b), 128(B)(4)(d), 

128(B)(5)(d)-(e), 128(C), 128(C)(1), 128(C)(1)(a)-

(c), 128(C)(2), 128(C)(2)(a)-(b), 128(C)(3), 

128(C)(4), 128(C)(4)(a)-(b), 128(C)(5), 

128(C)(5)(a)-(c), 128(D)-(E), 128(F), 128(F)(2), 

128(F)(2)(a)-(c), 128(F)(3), 128(F)(4)(a)-(b), 

128(G), 128(G)(2), 128(G)(2)(a)-(c), 128(G)(3), 

128(G)(3)(a)-(b), 128(H), 128(H)(1), 128(H)(1)(a)-

(c), 128(H)(2), 128(I)-(K), 128(L), 128(L)(2), 

128(L)(2)(b)(ii), 128(L)(2)(c), 129(A), 135(A)-(B), 

136, 137(A), 137(B), 137(B)(2)(c)-(d), 137(D)(1), 

137(E)(1)-(3), 137(E)(4)(f), 137(F), 137(F)(1)-(2), 

138, 138(A)-(C), 138(D), 138(D)(1), 138(E), 

138(E)(1)-(2), 138(F), 138(F)(5), 138(F)(7)-(8), 

138(G), 138(G)-(J), 139(A)(2), 140(A)(1)-(3), 

140(B)(1), 140(C), 140(C)(1)-(2), 143, 143(A)-(C), 

144, 145, 146, 146(A)-(B), 147, 147(A)-(C), 148, 

11/2/2006 
- 23 - 

149, 149(A)-(D), 150, 150(D), 151, 151(A), 

151(A)(4)(d), 152, 153, 154. 

2(C)(4), 2(C)(5), 7(V), 124(A), 128(B)(4), 

128(B)(5), 128(I)(1), 128(I)(2), 128(I)(3), 128(J), 

128(K), 128(L)(1), 135, 135(A), 138(F)(9), 

138(F)(10), 148, 148(B), 148(B)(1)(a)-(e), 

148(B)(2), 148(B)(3), 148(C)(4), 148(C)(5), 

150(A), 151(A)(2), 151(A)(4)(d), 151(B). 

6/27/2007 

2(C)(5), 2(E), 7(AC), 7(AU), 7(AV), 111(A), 

111(B), 112(B), 112(C), 113(C), 115, 122, 124(A), 

125, 125(A)(1), 125(D), 128(E)(2), 128(E)(2)(e), 

128(L)(2)(a), 133, 134, 134(E), 135(A), 135(B), 

137(B), 137(D)(2), 137(D)(3), 138(F)(10), 

138(G)(3), 139(A)(2), 140(A)(1), 140(A)(2), 

148(A)(3), 148(B)(1)(a), 151(A)(1)(b), 

151(A)(1)(f), and 151(A)(1)(k). 

5/13/2009 

Table 5 –Revisions to NMAC 20.2.99, Sections Being Approved by EPA 

(by submittal date) 

NMAC 20.2.99 Section Submittal Date to EPA 

109, 114, 116, 117, 118, 120, 121, 123, 129, 136, 

143, 144, 145, 146, 147, 149, 152, 153, 154 

11/2/2006 

150 6/27/2007 

2, 7, 111, 112, 113, 115, 122, 124, 125, 128, 133, 

134, 135, 137, 138, 139, 140, 148, 151 

5/13/2009 

EPA Conclusion and Recommendation

I recommend approval of revisions to the New Mexico SIP and associated rules which were 

submitted by NMED on November 2, 2006, June 27, 2007, and May 13, 2009. I have reviewed 

these rules and find these revisions achieve the purpose of bringing the state SIP and associated 

rules into alignment with federal statutes and regulations. We have evaluated the State’s 

submittals and have determined that they meet the applicable requirements of the Clean Air Act 

and EPA regulations, and are consistent with EPA policy.