01043509

Component

Isolated rural 8-hour ozone non-attainment and maintenance areas (hereafter: rural areas) need to make a conformity determination for regionally significant transportation projects. This paper presents guidance for project analysts charged with completing rural-area 8-hour ozone conformity analyses. Several analysis options are available to complete rural-area 8-hour ozone conformity determinations. In most circumstances, however, the simplest approach will be for project analysts to use the “less-than-base-year” emissions test to assess whether a project will pass conformity. The less-than-base-year test involves estimating emissions for the base year, 2002 for 8-hour ozone analyses, and comparing emissions that occur during the base year to emissions that occur in future years, assuming the project is completed. If future year emissions are less than those estimated for 2002, the project will pass the conformity test. On-road motor vehicle emissions are projected to decline substantially in future years, due to the replacement of older, higher-polluting vehicles, with newer, cleaner-operating vehicles. Given the substantial forecasted decline in on-road emissions, most projects will have little trouble passing the less-than-base-year emissions test, unless the project results in a substantial increase in regional vehicle miles traveled (VMT). For the less-than-base-year test, we present a simplified analysis procedure relying on EMFAC (EMFAC is the California motor vehicle emissions model) projections of VMT and making simple assumptions about changes in traffic flow. For analyses where these assumptions are not sufficiently precise, a more detailed procedure is outlined.

01042056

07-0822

English

22p

2007

Transportation Research Board 86th Annual Meeting

CD-ROM

Figures (4) ; References (21) ; Tables (7)

Air quality management; Assessments; Emission control systems; Exhaust gases; Nonattainment areas; Ozone; Pollutants; Project management; Rural areas; Transportation planning; Vehicle miles of travel

Administration and Management; Energy; Environment; Finance; Highways; Vehicles and Equipment; I15: Environment

Transportation Research Board Annual Meeting 2007 Paper #07-0822

TRIS, TRB

Feb 8 2007 5:24PM