ODOR AND HYDROGEN SULFIDE EMISSION FROM A DAIRY MANURE STORAGE

Ambient H2S air concentrations were measured continuously for a period of approximately 30days around a manure storage basin at a 700-dairy cow operation in Minnesota. Manure wasagitated and pumped from the basin during the first week of monitoring. Odor samples were takenon two different occasions during the monitoring period using a wind tunnel placed just above themanure basin surface. Odor plume measurements were also made, but on a single day only. Barn emissions did not seem to contribute much to hydrogen sulfide concentrations measuredaround the manure storage. This was verified by sorting the H2S measurements obtained whenwind was blowing from the barn toward the manure storage for the two monitors located at thesouth side of the basin. Mean H2S concentrations downwind of the barn were between 0.02 and5.7 ppb, while mean H2S concentrations around the storage varied between 0.9 and 20 ppb. A limited number of odor samples taken during the monitoring period suggested that the manurestorage contributed significantly to odor emission as compared to the barn. Emission from thestorage was between 7 and 10 OU/m2-s, while emission from the barn was between 2 and 3OU/m2-s. Odor plume measurements taken at 60 and 120 m downwind from the barn indicated adecrease of 10 OU per 60 m.