HR: 1340h
AN: H43B-0375 [Abstracts]
TI: Transport of microorganisms in the presence and absence of manure suspensions
AU: * Bradford, S A
EM: sbradford@ussl.ars.usda.gov
AF: USDA-ARS, Salinity Laboratory, 450 W. Big Springs Road, Riverside, CA 92507-4617
United States
AU: Tadassa, Y
EM: ytadassa@ussl.ars.usda.gov
AF: USDA-ARS, Salinity Laboratory, 450 W. Big Springs Road, Riverside, CA 92507-4617
United States
AU: Bettahar, M
EM: Mehdi.Bettahar@parsons.com
AF: Parsons, 100 West Walnut Street, Pasadena, CA 91124
United States
AB:
Wash water and storm water runoff from Concentrated Animal Feeding Operations (CAFOs) frequently contain manure and a variety
of viral, bacterial, and protozoan parasite pathogens. Column experiments were conducted to elucidate the transport
behavior of representative microbes (coliphage, Escherichia coli O157:H7, and Giardia cysts) through several aquifer sands in
the presence and absence of manure suspensions. Specific factors that were considered include the soil grain size
distribution, the presence and absence of manure suspensions, and manure size distribution. Effluent concentration curves
and the final spatial distributions of microorganisms and manure particles were measured. Increasing the microbe size and
decreasing the median grain size of the sand resulted in low effluent concentrations and increased retention of the microbes,
especially in the sand near the column inlet. Similar transport trends were observed for the manure suspensions in these
sands. The spatial distributions of retained microbes and manure were generally not consistent with predictions from
conventional attachment, detachment, and blocking models; but rather with straining. The transport potential of the microbes
was sometimes enhanced in the presence of manure suspensions. This observation, as well transport and retention data for
manure suspensions, suggest that manure components filled straining sites and inhibited microbe retention. Differences in
the surface charge properties of clean and manure equilibrated microbes (presumably due to adsorption of organic components
from the suspension) may also influence transport behavior.
DE: 1831 Groundwater quality
DE: 1832 Groundwater transport
SC: Hydrology [H]
MN: 2004 AGU Fall Meeting