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Ammonia (NH3) emission from a grow‐finish swine (Sus scrofa) building with an underfloor manure storage pit was evaluated during warm weather from 26 June to 25 September. Average daily mean (ADM, covering all measurement days) outdoor temperature was 21.8°C. Ammonia concentrations, ventilation rates, and temperatures were continuously measured or recorded and 88 d of reliable data were obtained. Air samples were taken at wall and pit exhaust fans and in the pit headspace. The NH3 concentrations were monitored on‐site with a chemiluminescence NH3 analyzer. Ventilation rates were calculated based on operation of five wall fans, four pit fans, and the fan static pressure. The NH3 emission rates were calculated by multiplying simultaneously measured NH3 concentrations and ventilation rates of wall and pit exhaust fans. The ADM of building NH3 concentration (mean concentration of all sampling locations) was 3.9 mg m−1. The ADM building NH, emission (sum of the emissions from all ventilation fans) was 11.2 kg d−1, equivalent to 145 g d−1 per AU (animal unit = 500 kg animal weight). The ADM emission per AU was higher than other reported values, probably due to warmer temperatures and higher ventilation rates. The building NH3 concentrations were inversely proportional to the indoor temperatures (r = −0.66) and ventilation rates (r = −0.59) and correlated well to total pig weight (r = 0.49). The building NH3 emission rates were correlated to total pig weights (r = 0.52) and ventilation rates (r = 0.41) and were not well correlated to indoor temperatures (r = 0.12).

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Our purpose in conducting these studies was to examine photolysis as a destructive process for polychlorobiphenyls (PCBs) extracted from soils with surfactant solutions. Surfactants have shown promise as agents for removing free phase and sorbed contaminants from soils, yet information on ultimate disposal options and recycle/recovery strategies for the surfactants is generally lacking. For arylhalides, photodechlorination may result in decontamination, eliminating the need to physically separate these contaminants from the washing solution. Photochemical reactions of the PCB congener mixture, Aroclor 1254, and the specific congener, 2,3,4,5-tetrachlorobiphenyl (2,3,4,5-TeCB), were investigated in aqueous solutions containing surfactant micelles with UV light at 253.7 nm. Photoreduction through photodechlorination was shown to be the main decay pathway in which lesser chlorinated congeners were formed as intermediates. In experiments with 2,3,4,5-TeCB, final noncarbon-containing products included Cland H + , both produced nearly stoichiometrically from the starting materials. The quantum yield for decay of 0.1 µM 2,3,4,5-TeCB in 0.5 mM Brij 58 micellar solutions was over six times greater than in water alone. Sequential extraction from a soil and photoreduction of 2,3,4,5-tetrachlorobiphenyl by Brij 58 solutions proved to be limited by surfactant loss to the soil.

Hydrogen sulfide (H 2 S) is an odorous gas produced from animal manure. It is toxic to humans and animals at high concentrations. There is little understanding about its release behavior from stored liquid swine manure. This paper documents burst releases of H 2 S recorded with a state-of-the-art field measurement system in two commercial swine buildings over a six-month period. The 1,000-head grow-finish buildings had 2.4 m deep manure collection and storage pits under fully slatted floors. They were mechanically ventilated with pit chimney fans and end wall exhaust fans. Pit chimney ventilation rates were continuously measured with full-size fan-impeller anemometers. End wall fan ventilation rates were calculated from continuously recorded fan operation times and differential static pressures. Concentrations of H 2 S in the sampled air streams were measured with an H 2 S converter and an SO 2 analyzer for each building. Sample air was continuously pumped from three locations: pit fans, wall fans and pit headspaces. Hydrogen sulfide concentrations at each location were acquired for 10 or 15 minutes during each 60 or 90 minute sampling period, respectively.A burst release of H 2 S was defined as a sudden increase (100% or greater) of H 2 S release rate measured during any period compared to previous periods, under relatively constant ventilation rates and indoor room temperatures. A total of 83 burst releases were identified in the data of 219 days with reliable measurements. Releases of ammonia (NH 3 ), which were simultaneously and continually measured, were verified to confirm that the burst H 2 S releases were unique. Typical burst H 2 S releases were presented graphically. Time distributions of the bursts were studied. The burst H 2 S releases were not related to any factors known to affect NH 3 releases from liquid manure. Further research is needed to explain the causes of the burst releases documented in this paper.