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Toxic Substances Hydrology Program

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Research Projects - Emerging Contaminants
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Transport Through the Unsaturated Zone

Soil collection and equipment used for lab-column experiments

Soil collection and equipment used for lab-column experiments

Soil collection and equipment used for lab-column experiments

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View to base of soil column showing set-up used for collection of effluent that has traveled through the soil column. Sensor inserted into column on right side monitors temperature of effluent before it enters collection bottle
View to base of soil column showing set-up used for collection of effluent that has traveled through the soil column. Sensor inserted into column on right side monitors temperature of effluent before it enters collection bottle

(click on image for larger version)

Lab-column study. Soil samples were collected by the USGS in proximity of swine operations in Iowa, North Carolina, and Missouri that are being used in lab-column experiments being collaboratively conducted by Dr. Craig Adams (University of Missouri - Rolla). The results will help understand the chemical processes that affected the transport of antibiotics through the unsaturated zone. Initial experimental work focused on developing column techniques to allow a high level of reproducibility between and within column runs. Breakthrough curves for tylosin, sulfadimethoxine, sulfamethoxazole, sulfadichloropyridazine, sulfamethazine, sulfamerazine, sulfthiozole, sulfamethazole, carbadox, chlorotetracycline and oxytetracycline have been conducted. Initial results have shown that the sulfanomides are highly mobile. In contrast, carbodox and tylosin were found to have greater amounts retardation in transport. A mathematical model will be developed to predict transport through the unsaturated zone.

Soil-column study. A proof-of-concept experiment was devised in collaboration with the U.S. Department of Agriculture, Water Conservation Laboratory to determine if emerging contaminants, as well as pathogens, found in treated effluent could be transported through a 2.4 m soil column and, thus, potentially reach ground water under recharge conditions similar to those in arid or semiarid climates. Samples were analyzed for 131 emerging contaminans including veterinary and human antibiotics, other prescription and nonprescription drugs, widely used household and industrial chemicals, steroids and reproductive hormones. After percolating through the soil column, 18 fewer compounds were detected in the effluent than the influent samples and the total concentration decreased by more than 70%. These compounds may have been subject to transformation (biotic and abiotic), adsorption, and (or) volatilization in the storage tank and during travel through the soil column. Eight compounds—carbamazapine; sulfamethoxazole; benzophenone; 5-methyl–1Hbenzotriazole; N, N-diethyltoluamide; tributylphosphate; tri(2-chloroethyl) phosphate; and cholesterol—were detected in both influent and effluent samples indicating they have the potential to reach ground water under recharge conditions similar to those in the soil column.

Available Publications

Cordy, G., Duran, N., Bower, H., Rice, R., Kolpin, D.W., Furlong, E.T., Zaugg, S.D., Meyer, M.T., and Barber, L.B., 2004, Do pharmaceuticals, pathogens, and other organic waste water compounds persist when waste water is used for recharge?: Ground Water Monitoring and Remediation, v. 24, no. 2, p. 58-69.

Related Headlines

More Information

  • Project contact: Mike Meyer (lab-column study)
  • Project Contact: Gail Cordy (soil-column study).

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