MARGARET WHITE SPRINGS RECHARGE STUDY, BUFFALO NATIONAL RIVER, NORTH-CENTRAL ARKANSAS, USA

Determination of recharge areas to Margaret White Springs is critical for protecting water quality along the middle reaches of the Buffalo National River and understanding the interaction of groundwater and surface water in the Springfield Plateau karst region of northern Arkansas. Margaret White Springs are poorly characterized despite considerable contribution to stream flow. Groundwater movement in the Springfield Plateau aquifer is complex, and flow paths often cross surface divides. Spring discharge temperatures at Margaret White Springs are colder than the river upstream. The spring recharge area and connectivity with the St. Joe Fault were evaluated using dye tracing techniques. Reactive charcoal samplers (bugs) were deployed in Margaret White Springs and several other springs in the area to identify dye movement. Three fluorescent dyes (Fluorescein, Rhodamine WT, and Eosine) were injected north of the Margaret White Springs emergence, outside the watershed boundary, during a large storm event. The dye-injection locations included two sinkholes and within Mill Creek. The bugs deployed at Margaret White Springs and other local springs did not detect dye from the initial dye injection. Results to date exclude the Mill Creek/St. Joe fault area to the northeast as a likely recharge zone and suggest groundwater movement is not northeast to southwest during recharge events.