Dr. Bryan L. Woodbury is an Agricultural Engineer examining cost-effective and sustainable solutions that reduce negative environmental effects from beef cattle feedlots. These effects can be realized in air, soil, surface and groundwater contamination.  Air quality research includes evaluating the nitrogen and total reduced sulfur emissions from feedlot soils.  Additionally, portable sampling equipment and electromagnetic sensing techniques were developed to facilitate mapping the spatial variability of gaseous emissions (i.e. nitrous oxide, carbon dioxide, ammonia, total reduced sulfur etc.) from feedlot surfaces.  Understanding this spatial variability will aid in developing targeted practices for control. Soil quality research is investigating the management of cover crops for nutrient retention of land applied animal manure.  Cover crops (wheat or rye) planted after crop removal have been shown to retain nutrients but can reduce crop yields.  Late fall or early spring destruction of the cover crop may retain nutrients and minimize crop yield reductions.  Runoff from feedlots can potentially contaminate surface and groundwater.  Traditional runoff control systems store liquid in holding ponds for later application to crop land.  These storage ponds are expensive to build and  maintain, as well as being unsightly and a potential seepage source for groundwater contamination.  Research on alternative runoff control systems that feature short-term liquid storage for solids removal  and a vegetative hay field for nutrient and water utilization, with no long term liquid storage, have been demonstrated to effectively control feedlot runoff.  Research is on-going on these systems to determine their long-term performance and sustainability.