Fate and Transport of 17 B-Estradiol in Karst Aquifers of the Ozark PlateauEPA Grant Number: U915754
Title: Fate and Transport of 17 B-Estradiol in Karst Aquifers of the Ozark Plateau
Investigators: Peterson, Eric W.
Institution: University of Missouri - St Louis
EPA Project Officer: Boddie, Georgette
Project Period: August 1, 2000 through August 1, 2003
Project Amount: $77,754
RFA: STAR Graduate Fellowships (2000) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Ecological Indicators/Assessment/Restoration , Fellowship - Earth Sciences
The objective of this research project is to assess the transport and fate of 17 B-estradiol (E2) through karst systems, focusing on the following pathways: (1) movement into and out of the rock matrix, (2) movement through the sediment pile, (3) degradation, or (4) movement through the conduits until discharged at the springs.
A numerical model will be created that includes the E2 pathways and the associated fluxes. The numerical model will focus on the pathways listed in the objectives/hypothesis section. For transport in the conduit/rock matrix, a numerical model simulating contaminant transport through fractured rock will be applied. MODFLOW will be used to simulate the transport of E2 through the sediment piles. The transport through the conduit system will be modeled using the EPA's stormwater management model (SWMM). Although designed for storm sewers, similarities exist between storm sewers and karst systems. Preliminary work (Peterson and Wicks, 2000) has shown that SWMM can be applied to branchwork conduit systems. Degradation of E2 in both the water and the sediment will be performed in the laboratory setting. For both mediums, two subsets will be created. One subset will be treated with mercuric chloride to effectively kill the biological activity within the sample. This subset will serve as the control. The second subset will be untreated water or sediment from a karst system. The samples will be analyzed for E2 every 3 to 5 days for a period of 30 days. The concentration of E2 in water will be determined using ELISA (enzyme-linked immunosorbent assay) kits. The ELISA kits operate on the basis of competition between an enzyme conjugate and the E2 in the sample for a limited number of binding sites on the antibody coated plate. Quantitative test results are obtained by measuring the absorbance of the samples and standards with a microplate reader at the 650 mm wavelength.
This research will contribute to a better understanding of E2 transport within the karst aquifer setting. This information will help further the overall understanding of fluid and contaminant movement within karst aquifers. The data also will indicate whether acute and chronic dosages of E2 are delivered to aquatic species. These results should provide a basis for future biological work to assess the impact that E2 exposure has had on aquatic species in the environment.