Early Results from a Study of Ammonium Ion Deposition in the Shenandoah Valley of Virginia

The Shenandoah Valley of Virginia has many poultry houses thought to be the cause of increased ammonium deposition. Rain gauges were placed at four sites in the valley and the precipitation was tested for nitrate, sulfate and ammonium ions. The first year of the study found that the valley in general has a higher than national average ammonium level in rainfall, there is a strong seasonal increase in ammonium concentration during the spring, and that close proximity to these poultry houses shows even more impact. Data also indicates that ammonium ion concentrations are higher in lower rainfall events. The study is in its early stages, with limited statistical evaluation, and expects more complete results over the next 5 years.*

*This project is funded by the EPA’s Chesapeake Bay Program