Analytical methods for monitoring the volatile organic compound (VOC) emissions, for defining atmospheric transport coefficients, and for monitoring solution phase chemistry have been developed to define processes regulating emission of malodorous and other VOCs from a high odor swine production facility. Of the 40 organic compounds identified in liquid and outdoor air samples from the swine production facility, 27 VOCs were confirmed to contribute to decreased air quality in the vicinity of the facility. Specifically, C2 through C9 organic acids demonstrated the greatest potential for decreased air quality, since these compounds exhibited the highest transport coefficients and highest airborne concentrations. Flux measurements suggested that the total rate of nonmethane VOC emissions from the deep basin swine waste storage system was 500‐ to 5700‐fold greater than established nonmethane VOC fluxes from nonanthropogenic sources. The volatilization rate of malodorous and other VOCs from the stored swine waste was positively correlated with wind velocity between 0.2 and 9.4 m s−1, and a maximum concentration of VOCs present in the air was observed to occur at a wind velocity of 3.6 m s−1. Experimental Henry's law coefficients adequately predicted the transport efficiency observed for some of the VOC emissions measured from air samples taken at 0, 25, and 100 m from the swine waste storage basin; however, results indicated that laboratory‐based extraction procedures, currently used to estimate malodor potential for swine slurry samples, provide an inaccurate representation of malodorous and other airborne VOCs actually present in the air near swine production facilities.

CWEX demonstrates the importance of collecting field measurements within a wind farm to facilitate basic understanding of the three-way interactions among wind energy, meteorology, and crop agriculture.

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The distribution and dissipation of alachlor [2-chloro-2′,6′-diethyl-N-(methoxymethyl) acetanilide], atrazine (2-chloro-4-ethylamino-6-isopropylamino-1,3,5 triazine), and metribuzin [4-amino-6-(1,1-dimethylethyl)-3-(methylthio)-1,2,4-triazin-5(4H)-one] in soil were studied in 1990, 1991, and 1992. Crop management practices included four tillage methods-chisel plow, moldboard plow, no-till, and ridge-till-and two crop rotations-continuous corn (Zea mays L.) and a corn-soybean [Glycine max (L.) Merr.] rotation. All herbicides were broadcast-spray applied with no incorporation. No-till plots had the smallest amounts of alachlor and metribuzin, whereas ridge-till plots had the smallest amounts of atrazine. Moldboard-plow plots usually contained the highest amounts of all three herbicides, although ridge-till plots had the highest metribuzin levels in 1992. These differences were seldom significant at the 0.05 level of probability, however. Throughout the growing season, 50 to 84% of the alachlor and metribuzin were retained in the top 10-cm layer of soil, and at least 68% of the atrazine was retained in the top 20 cm. From 84 to 98% of the herbicide applied was lost each year, probably by microbial degradation and, for alachlor, by volatilization after application. First-order half-lives were 36 d for alachlor, 55 d for atrazine, and 32 d for metribuzin. A two-compartment model better fitting the alachlor data returned a half-life of 24 d for that herbicide.

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