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2004 and 2005 Transportation Conformity Rule Amendments Outreach Activities

Session 4: Regional Emissions Tests for the New Standards

FHWA Transportation Conformity and CMAQ Workshop
Summer 2004


General: Regional Emissions Analyses


General Changes to Baseline Year Tests


General Changes to.Build/No-Build Test


Areas Covered by Final Rule


Tests for 8-hour Areas .without 1-hour SIPs


Tests for 8-hour Areas .without 1-hour SIPs


8-hour Areas with 1-hour SIPs


8-hour Areas with .1-Hour Budgets

Four groupings of a solid yellow circle representing a 1-hr area and a clear circle representing an 8-hr area. They are: the 1-hr area and the 8-hr area are the same; the 1-hr area fully encompasses and is larger than the 8-hr area; the 8-hr area fully encompasses and is larger than the 1-hr area; and the two circles partially overlap.

Scenario 1 -- 93.109(e)(2)(i)

A solid yellow circle representing a 1-hr area and a clear circle representing an 8-hr area. The 1-hr area and the 8-hr area are the same.

Baton Rouge, LA

map showing Baton Rouge 8-hour Area (parishes of West Baton Rouge, East Baton Rouge, Iberville, Ascension, and Livingston), 1-hr Ozone Area (the same area). The MPO consists of the large portions of the parishes of East Baton Rouge and Ascension as well as portions the parishes of of West Baton Rouge and Livingston

Scenario 2 -- 93.109(e)(2)(ii)

A solid yellow circle representing a 1-hr area and a clear circle representing an 8-hr area. The 1-hr area fully encompasses and is larger than the 8-hr area

Scenario 3 -- 93.109(e)(2)(iii)

A solid yellow circle representing a 1-hr area and a clear circle representing an 8-hr area. The 8-hr area fully encompasses and is larger than the 1-hr area

Dallas - Fort Worth, Texas

map showing Dallas-Ft. Worth 8-hour Area (counties of Denton, Collin, Parker, Tarrant, Dallas, Rockwell, Johnson, Ellis, and Kaufman), 1-hr Ozone Area (counties of Denton, Collin, Tarrant, and Dallas). The MPO consists of the counties of Denton, Collin, Tarrant, Dallas, and Dallas, Rockwell as well as portions of Parker, Johnson, Ellis, and Kaufman counties

Scenario 4 -- 93.109(e)(2)(iv)

A solid yellow circle representing a 1-hr area and a clear circle representing an 8-hr area. The two circles partially overlap.

Frederickburg, VA

map showing Frederickburg 8-hour Area (Frederickburg and counties of Spotsylvania and Stafford), DC-MD-VA 8-hr Area (Manassas, Manassas Park, and the counties of Prince William and Fairfax), 1-hr Ozone Area (Stafford County and the DC-MD-VA 8-hr Area). Each of the two 8-hr areas are also MPOs

Before Areas Have 8-hour SIPs:.General Principles


Before Areas Have 8-hour SIPs:.General Principles


When may a 1-hour SIP budget .not be appropriate?


Examples of when a 1-hour SIP budget not be appropriate


Once Areas Have .8-hour or PM2.5 SIPs


Once Areas Have SIP Budgets


Timely Implementation of TCMs

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