Item A: Public Hearing onMetro Plan Amendment (Delta Sand and Gravel)

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Delta Sand & Gravel: Haul Road Analvsis 01NOV06 Lane Regional Air Protection Agency Screellillg Assessment, Delta Sand & Gravel, Co. (Pennit No. 202119), Novelllber 1, 2006. Tllis describes the basis for tIle attaclled Screening Assessmellt prepared for Delta Salld & Gravel Co., 999 Division Road, Eugene, Oregoll. Tllis facility is proposing to shift the location of its llaul road. TIle Lane Regional Air Protection Agency (LRAP A) is including this Assessnlent in the evaluation of tile facility pemlit rellewal assessmellt. Particulate matter (PM) frolll tIle haul road will be fugitive dust. LRAP A staff evaluated the possible inlpact of PM emissions fronl the proposed llaul road. The emissions from the sand and gavel processing (screening, crusllers, and conveyers) were not evaluated in the haul road Screening Assessmellt. For residents who live or work near the haul road, the assessment includes tIle assumption that exposures are continuous for 8 hours per work day, 260 operating days. Vehicle miles traveled (VMT) by the haul trucks road and mitigation measures are also estimated as part of the assessment. This PM impact is expressed in terms of the micrograms per cubic meter (Jlg/m3). The EP A regulatory nlodel AERMOD was used to perform the analysis. Local meteorological data was acquired from the EPA's Support Center for Regulatory Atmospheric Modeling. The most current year available is 1991. Plant site and source locations were taken from measurement of an aerial photograph provided by Delta S&G. LRAPA staff verified the scale of this photograph using a handheld GPS. The model was executed using an option to determine PM10 compliance witll the' NAAQS. Compliance with the 24-hour standard for PM10 is computed using the 3-year average of the annual 99th percentile. AERMOD estimates this by using the 4th highest value for a single year of meteorological data. Therefore, all receptor peak concentrations represent the 4th highest concentration for the input set. For this modeling, a receptor grid extended from the plant boundary to a distance of 1000 nleters. Receptors were spaced at a 50 meter interval for the first 500 meters, with 100 meter spacing for the remainder of the grid. · As expected for these fugitive PMl 0 emissions, the highest concentrations occur at the plant boundary and decrease with distance. The analysis shows that the currellt llaul road produces the highest concentrations, where the road closely parallels the eastern boundary. Most of the offsite impacts from the current route are in unpopulated areas along the Willamette River. The modeled impacts from each haul road, added to ambient monitored concentrations, is below the PM 10 National Ambient Air Quality Standards. Isopleths of impacts for each route, including maximum values, are attached. Also included is a wind rose of the 1991 meteorological data set used. ~