Revision to Maryland’s Transportation 

Conformity State Implementation Plan 

SIP Revision 06-07 

November 9, 2006 

Prepared for: 

U.S. Environmental Protection Agency 

Prepared by: 

Maryland Department of the Environment 

MARYLAND DEPARTMENT OF THE ENVIRONMENT 

1800 Washington Boulevard • Baltimore MD 21230 

410-537-3000 • 1-800-633-6101 

Robert L. Ehrlich, Jr. 

Governor 

Michael S. Steele

Lt. Governor 

Kendl P. Philbrick

 Secretary

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TABLE OF CONTENTS 

Executive Summary.......................................................................................................... 4 

Introduction and Background ......................................................................................... 6 

What is a SIP?................................................................................................................. 6 

What is SAFETEA-LU? ................................................................................................. 6 

What is Transportation Conformity? .............................................................................. 7 

Maryland Interagency Consultation............................................................................... 8 

Maryland Commitments: New SAFETEA-LU Requirements..................................... 9 

Substitution of Transportation Control Measures........................................................... 9 

PM2.5 and CO Hotspots................................................................................................. 9 

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Executive Summary 

This SIP revision formally revises the Maryland Transportation Conformity State 

Implementation Plan (SIP 03-02) to reflect changes in the conformity process that have 

resulted from the enactment of SAFETEA-LU (Safe, Accountable, Flexible, Efficient 

Transportation Equity Act: A Legacy for Users (SAFETEA-LU) and the designation of 

Washington County by the EPA as a nonattainment area for fine particulate matter 

(PM2.5). Transportation conformity is a requirement of the Clean Air Act (CAA) that 

helps control growth in mobile source emissions for areas that do not meet federal air 

quality standards. 

SAFETEA-LU Conformity Process Changes 

The Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for 

Users (SAFETEA-LU) was enacted on August 10, 2005. Under this act, amendments

were made to the transportation conformity rules (Section 6011 of the Act), which require 

states that have nonattainment areas to revise their existing transportation conformity 

SIPs. The major transportation conformity amendments brought about by the enactment 

of SAFETEA-LU consist of: 

• The frequency of required conformity determinations is now every four years 

(instead of every three years) unless the Metropolitan Planning Organization 

(MPO) elects to update its transportation plan more frequently 

• The act allows areas two years instead of the previous 18 months to determine 

conformity after EPA approves or finds an nonattainment area’s mobile budgets 

adequate 

• Areas now have the option to shorten the horizon of transportation plan 

conformity determinations 

• The latest year of a transportation plan can now be the latest of the following: the 

10th year of plan, the latest year in a SIP that contains a motor vehicle emission 

budget, or the year after the completion date of a regionally significant project 

• The act gives nonattainment areas an additional 6 months to re-determine 

conformity after new motor vehicle emission budget (MVEB) is found adequate, 

approved or promulgated 

• The act grants a streamlined ability for states to substitute Transportation Control 

Measures (TCM’s) without having TCM substitution language in their SIPs 

• The act adds a one-year grace period to conformity lapses 

• The act streamlines requirements for conformity SIPs 

• The act requires nonattainment areas to perform a qualitative analysis of PM2.5 

hotspots for projects that EPA designates of “air quality concern” such as 

highway and transit projects that involve significant levels of diesel vehicle traffic 

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Maryland Nonattainment Areas and SAFETEA-LU 

On December 17, 2004, EPA designated Washington County as being in nonattainment 

of the federal PM2.5 standard, thus making a transportation conformity determination 

required for proposed transportation projects in this county. Under the rules of 

transportation conformity it is required that a public interagency consultation process be 

maintained. The Maryland Department of the Environment (MDE) has revised (as seen 

in Appendix A of this SIP revision) the transportation conformity regulations for 

Maryland that address the interagency consultation process to include Washington 

County. 

The local Metropolitan Planning Organization (MPO) which is called the Hagerstown/ 

Eastern Panhandle Metropolitan Planning Organization (HEPMPO) is now charged with 

establishing a proactive public involvement process which provides a reasonable 

opportunity for review and comment before taking action on a conformity determination 

for all transportation plans consistent with the requirements of 23 CFR section 

450.316(b). The MDE will be an active participant in this process. The addition of the 

HEPMPO interagency process will be codified in the revised Maryland conformity 

regulations under COMAR 26.11.26 (Appendix A). 

Under this SIP revision Maryland also commits meeting EPA requirements to complete 

carbon monoxide (CO) and fine particulate (PM 2.5) hotspot analyses for applicable 

transportation projects. Maryland also commits through the nonattainment areas MPOs 

to identify mitigation measures not specifically addressed in a Transportation 

Improvement Program (TIP) or Plan in accordance with 40 CFR Part 93.122, 842. 

References and Guidance 

This document references Maryland SIP #03-02, and uses guidance issued by EPA, 

FHWA, FTA, and USDOT on hotspot analyses and SAFETEA-LU conformity 

provisions. Additional guidance was found in Section 7 of EPA’s February 2006 

document, Interim Guidance for Implementing the Transportation Conformity Provisions 

in the Safe, Accountable, Flexible, Efficient Transportation Equity Act: A Legacy for 

Users (SAFETEA-LU), and Section 6011 of the SAFETEA-LU Act itself, which deals 

with transportation conformity. 

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Introduction and Background 

The purpose of this document is to revise the Maryland conformity SIP in accordance 

with the new requirements of SAFETEA-LU, an updated federal law. 

What is a SIP? 

The State Implementation Plan (SIP) is a plan for each State which identifies how that 

State will attain and/or maintain the primary and secondary National Ambient Air Quality 

Standards (NAAQS) set forth in section 109 of the Clean Air Act ("the Act") and 40 

Code of Federal Regulations 50.4 through 50.12 and which includes federallyenforceable requirements. Each State is required to have a SIP which contains control 

measures and strategies which demonstrate how each area will attain and maintain the 

NAAQS. These plans are developed through a public process, formally adopted by the 

State, and submitted by the Governor's designee to EPA. The Clean Air Act requires EPA 

to review each plan and any plan revisions and to approve the plan or plan revisions if 

consistent with the Clean Air Act. 

SIP requirements applicable to all areas are provided in section 110 of the Act. Part D of 

Title I of the Act specifies additional requirements applicable to nonattainment areas. 

Section 110 and part D describe the elements of a SIP and include, among other things, 

emission inventories, a monitoring network, an air quality analysis, modeling, attainment 

demonstrations, enforcement mechanisms, and regulations which have been adopted by 

the State to attain or maintain NAAQS. EPA has adopted regulatory requirements which 

spell out the procedures for preparing, adopting and submitting SIPs and SIP revisions 

that are codified in 40 CFR part 51. EPA's action on each State's SIP is promulgated in 

40 CFR part 52. 

The contents of a typical SIP fall into several categories: (1) State-adopted control 

measures which consists of either rules/regulations or source-specific requirements (e.g., 

orders and consent decrees); (2) State-submitted comprehensive air quality plans, such as 

attainment plans, maintenance plans rate of progress plans, and transportation control 

plans demonstrating how these state regulatory and source-specific controls, in 

conjunction with federal programs, will bring and/or keep air quality in compliance with 

federal air quality standards; (3) State- submitted "non-regulatory" requirements, such as 

emission inventories, small business compliance assistance programs; statutes 

demonstrating legal authority, monitoring networks, etc.); and (4) additional requirements 

promulgated by EPA (in the absence of a commensurate State provision) to satisfy a 

mandatory section 110 or part D (Clean Air Act) requirement. 

What is SAFETEA-LU? 

On August 10, 2005, President Bush signed into law the Safe, Accountable, Flexible, 

Efficient Transportation Equity Act: A Legacy for Users (SAFETEA-LU). The act 

guarantees funding for highways, highway safety, and public transportation. SAFETEALU builds on two prior transportation bills - the Intermodal Surface Transportation 

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Efficiency Act of 1991 (ISTEA) and the Transportation Equity Act for the 21st Century 

(TEA-21). The act also revises several rules regarding transportation conformity. 

What is Transportation Conformity? 

Transportation conformity ("conformity") is a provision of the Clean Air Act that ensures 

that Federal funding and approval goes to those transportation activities that are 

consistent with air quality goals. Conformity applies to transportation plans and projects 

funded or approved by the Federal Highway Administration (FHWA) or the Federal 

Transit Administration (FTA) in areas that do not meet or previously have not met air 

quality standards for ozone, carbon monoxide, particulate matter, or nitrogen dioxide. 

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Maryland Interagency Consultation 

The transportation conformity rule, 40 CFR Section 93.105, requires that the State 

Implementation Plan (SIP) address how the principle agencies involved in the 

development of state implementation plans and the principle agencies involved in the 

continuing transportation planning process will consult with each other to reach 

consensus on important issues. 

COMAR 26.11.26, which has been included as Appendix A in this SIP document, has 

been revised to incorporate the changes in the federal conformity rule which were 

published in the SAFETEA-LU act on August 10, 2005. The primary purpose of the 

federal amendment is to streamline the administrative procedures and provide greater 

flexibility in the existing transportation conformity regulation. 

COMAR 26.11.26 has also been amended to provide a legal platform for the various 

consultation procedures that have been developed between the Maryland Department of 

the Environment (MDE), Maryland Department of Transportation (MDOT), and 

Metropolitan Planning Organizations (MPOs). The recent revisions to the federal rule to 

reduce the administrative complexity of the rule allow many decisions to be made 

through the interagency consultation process. The revisions to COMAR 26.11.26 give 

state and local governments increased flexibility to set performance measures used to 

determine conformity, develop the SIP, and handle unique planning situations in a 

manner beneficial to the environment and economic development. The general regulatory 

platform of COMAR 26.11.26.03 allows consultation to occur through a variety of 

processes. These processes are tailored to fit the resources and planning style of the area. 

In 2004 EPA designated Washington County as nonattainment for PM2.5, thus making a 

transportation conformity determination required for this pollutant in that nonattainment 

area. The local Metropolitan Planning Organization (MPO) which is called the 

Hagerstown/ Eastern Panhandle Metropolitan Planning Organization (HEPMPO) will 

establish a proactive public involvement process which provides a reasonable opportunity 

for review and comment before taking action on a conformity determination for all 

transportation plans and TIPs consistent with the requirements of 23 CFR section 

450.316(b). MDE will be very involved in this process and MDE commits to working 

with the HEPMPO on all PM2.5 conformity issues. MDE has formally added the 

HEPMPO interagency consultation process to Maryland’s Conformity regulation (see 

appendix A). 

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Maryland Commitments: New SAFETEA-LU Requirements 

Upon the passage of SAFETEA-LU, changes were made to the transportation conformity 

process. The major changes reflected in this SIP revision are commitments to identify and 

support emission control measures that are not specifically identified in a TIP or plan and 

a requirement to make an analysis of potential PM2.5 hotspots at transportation projects. 

Substitution of Transportation Control Measures 

The SAFETEA-LU Act provides for substitution of transportation control measures 

(TCMs) as an amendment to Section 176(c) of the Clean Air Act (42 U.S.C. 7506 (c)). 

40 CFR, Section 93.122(a)(4)(ii) which requires commitments for control measures not 

included in a TIP or Plan. 

An example of a commitment not included in a TIP or Plan would be a school bus retrofit 

project not being funded by FHWA or FTA, but is still being used for emission reduction 

credit in a conformity determination. Evidence needs to be identified that such a measure 

has adequate funding, personnel and authority for implementation, monitoring and 

enforcement. 

Maryland, in accordance with the requirements of 40 CFR Part 93.122, 842 commits to 

meeting this specific requirement of SAFETEA-LU. 

PM2.5 and CO Hotspots 

This provision applies to fine particulate (PM 2.5) hot spots and Carbon Monoxide (CO) 

and to project level conformity determinations only (in accordance with 40 CFR Part 

93.125(a)), not to regional conformity determinations. EPA’s Transportation Conformity 

Guidance for Qualitative Hot-spot Analysis in PM 2.5 and PM 10 Nonattainment and

Maintenance Areas describes how to conduct PM 2.5 hot-spot analyses for “projects of

air quality concern”, as defined in 40 CFR 93.123(b)(1). 

The final rule establishing transportation conformity criteria and procedures for 

determining which transportation projects must be analyzed for local air quality impacts 

in Particulate Matter (PM) 2.5 nonattainment and maintenance areas was published by 

EPA on March 10, 2006 (40 CFR 93.123(b)(1)). The EPA recommends under this final 

rule that an analysis be performed on potential PM2.5 hotspots for “projects of air quality 

concern” defined as projects which have a value of 8% or more projected annual average 

daily traffic comprised of diesel trucks. 

Maryland commits to meeting the requirements of the EPA hotspot rule(s) for PM2.5 and 

CO. 

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Appendix A 

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