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Air Quality <br />Construction of the proposed facility would also result in temporary increases in criteria <br />pollutants and dust. Air quality impacts would occur through emissions of carbon monoxide, <br />nitrogen oxides, hydrocarbons and other particulates from heavy equipment, and fugitive dust <br />from construction and earth-moving activities. Emissions from heavy equipment such as <br />bulldozers; mixers, and trucks can be estimated based on emission factors established by the <br />U.S. EPA. Expected emissions from operation of heavy equipment that might be used at the <br />construction site are shown in Table 3. The emissions listed are those presented in the <br />environmental assessment prepared for the new federal courthouse in downtown Portland <br />(Woodward-Clyde 1992b). The new federal courthouse in Eugene or Springfield is assumed for <br />the purposes of this evaluation to be roughly similar in size and to have the same required <br />construction activities. <br />Table 3. Estimated air emissions from operating heavy equipment on construction sites. <br /> <br />Equipment <br />CO Emission Factor (pounds per hour) <br />HC NOX SOX <br />Particulates <br />Wheeled dozer 1.794 0.192 4.166 0.348 0.165 <br />Off-highway truck 1.794 0.192 4.166 0.454 0.256 <br />Paver 1.794 0.192 4.166 0.454 0.256 <br />Concrete mixer 1.794 0.192 4.166 0.454 0.256 <br />Crane 0.125 0.018 0.375 3.55 0.0625 <br />Generator 1.0 0.143 3.6 .28.4 0.5 <br />Source: Woodward-Clyde 1992b; U.S. EPA 1985, 1995. <br />CO =carbon monoxide; HC =hydrocarbons; NOX =nitrogen oxides; SOX =sulfur dioxide. <br />In addition to the mobile equipment listed in Table 3, diesel-powered cranes, generators, and <br />compressors would likely be used during construction. In order to estimate emissions from the <br />heavy equipment, it is assumed that a crane uses approximately 25 gallons of fuel per hour and a <br />diesel generator uses approximately 20 gallons of fuel per hour when operated continuously <br />(Woodward-Clyde 1992b). Emissions of criteria pollutants from heavy machinery operation <br />during construction would create short-term impacts that would not interfere with attainment or <br />maintenance of long-term air quality standards. <br />Fugitive dust emissions generated from project construction can be estimated using the U.S. EPA <br />standard emission factor for construction of 1.2 tons of total suspended particulates per acre per <br />month. Estimating the PMIO fraction based on this value results in conservatively high estimates. <br />In addition, the emission factor assumes that construction occurs 30 days per month, which also <br />likely overestimates actual emissions. <br />Based on this conservative estimate, construction activities at the project site could produce <br />approximately 1.2 tons of airborne particulates per month, or approximately 8 to 10 pounds per <br />hour, depending on the length of the construction day. Activities required later in the <br />construction process, such as framing and interior construction, would not produce significant <br />Final. EIS 90 New Federal Courthouse <br />