|Lerch, Robert - Bob|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/18/2000
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Urbanization and agricultural land-use activities represent potential threats to the water quality and ecosystem integrity of Devils Icebox and Hunters Caves in Boone County. Both cave systems drain karst basins with surface and internally drained sources of water. Land use within the Devils Icebox watershed is primarily agricultural and urban, while Hunters Cave is spredominantly agricultural and forested. Since these cave systems have ver similar geologic and hydrologic settings, the impact of different land-use on water quality can be compared. Year-round monitoring was initiated in April 1999 to characterize the current water quality status of the main cave streams relative to nutrient, herbicide, and coliform bacterial contamination. Also, hydrogeologic parameters, including dissolved O2, pH, temperature, specific conductance, and turbidity are being continuously monitored. Water sampling for contaminants entails grab samples under baseflow at regular intervals and runoff event sampling using automated sampling equipment. Bacterial coliform analyses included quantitation of total and fecal coliforms on a quarterly basis. Total nitrogen (N) and phosphorus (P) concentrations, from April-July 1999, were generally low at both locations, but median total N and P concentrations were consistently higher at the Devils Icebox. Herbicide contamination was also low at both sites, with significant levels of atrazine briefly present from late April through May 1999. Fecal coliform concentrations were consistently higher at the Devils Icebox with levels ranging from 166 to 21,920 cfu/100 mL. The very high fecal coliform level at the Devils Icebox occurred in June 1999 following a runoff event. To date, contaminant data indicate that water quality impairment is greater for Devils Icebox than for Hunters Cave.