Submitted to: American Association for Aerosol Research
Publication Type: Abstract Only
Publication Acceptance Date: 4/25/2005
Publication Date: 10/17/2005
Citation: Purdy, C.W., Straus, D.C. 2005. Laser strategic aerosol data collected in feedyards of the High Plains [abstract]. In: Abstracts of 24th Annual American Association for Aerosol Research (AAAR) Conference, October 17-21, 2005, Austin, Texas. p. 53:1PH3.
Technical Abstract: Aerosolized particulates caused by farming, including concentrated animal feeding operations (CAFO’s), have come under increasing regulatory scrutiny. The concentration, size, and chemical composition of the dust particles need to be determined in open feedyards. Concentrations of aerosolized particulates that are 10 µm (PM10) or less in diameter are mandated not to exceed 150µg/m3 of air/24 hours, or exceed 50µg/m3 annually; the PM2.5 standard is not to exceed 65 µg/m3 in 24 hours or 15 µg/m3 annually. Recently the PM2.5 standard was modified by the Environmental Protection Agency (EPA) to include determining a temporal three-year and spatial averaging of concentrations. Four feedyards were examined using two Laser Strategic Aerosol monitors (SAM), one upwind and one downwind, over 8 days in the winter and summer. The SAM monitors sampled the air every 3 minutes at 1 m height and had a flow rate of 15L/min, and dust was weighed electro-optically. Particle size in µm was separated into nine classes (1.25, 3.00, 4.25, 6.00, 8.50, 12, 17, 24, and > 24). The overall statistical model statement showed a significant difference (P = 0.0001) between dust concentration downwind, 339 (±26) µg/m3 and upwind, 143 (±10) µg/m3. There was a significant difference in the mean overall emission data (µg/m3) for seasons [P = 0.0001; summer 428 (±47) and winter 234 (±25)], and feedyards (FY) [P >/= 0.001; FY1 192 (±25), FY2 460 (±53), FY3 341 (±48), and FY5 372 (±97)]. Highest dust concentrations occurred between 1800 and 2300 hours. The four feedyards exceeded the EPA PM10 standard.