Improving the Regional Scale OTAG Inventory for Future Urban-Scale Attainment Demonstrations

摘要

The OTAG inventory was created in the late 1995 and early 1996 for the purpose of supporting regional photochemical modeling. Since then, it has been improved and updated through numerous periods of review by EPA, states, industry, and the public and is now being used as the basis of EPA's regional NOx SIPcall. The group responsible for creating the inventory was given several months to construct the inventory for point, mobile, and area sources for all 38 states in the OTAG domain. Despite subsequent improvements, the inventory looks similar today to what it looked like in 1996, with the exception of Electric Generating Units(EGU's). The EGU data was replaced with EPA Acid Rain Division Continuous Emissions Monitoring Data. Although reasonable for regional scale analyses, certain revisions are necessary to support future urban scale modeled attainment demonstrations. The purpose of this paper is to discuss these necessary revisions. This paper will individually address each of the 3 major components of the most recently available SIP Call emissions inventory(point, Area, and On Road Mobile) for the 1995 base year inventory. Each analysis will look at possible problems with the inventory, the spatial and temporal extent of those problems, and the mass of emissions involved. In many instances an estimate of the emissions effects of the problem will be approximate given the difficulty of large scale recalculation of the emissions inventories. Unless otherwise noted emissions estimates will be in Tons of NOX Per Average Ozone Season Day.