ARSENIC RUNOFF FROM POULTRY FACTORIES. “Runoff measurements indicated that annual arsenic losses from these fields could range from 0.004 kilograms per hectare to 19 kilograms per hectare. Runoff with the largest arsenic loads was recorded in a ditch closest to a main point source of the contaminant — a shed where litter was stored.”
http://www.sciencedaily.com/releases/2010/08/100816095623.htm