CRF Finds New Karst Connection in Mineral King Valley Scientists of the Cave Research Foundation (CRF) with the cooperation of the National Park Service recently conducted a groundwater trace in a tributary to Mineral King Valley using two tracing agents during late August and early September. Both tracers were detected at dilute concentrations at Tufa Spring, but dye did not appear at Eagle Creek. White Chief Creek enters closed depressions in lower White Chief valley, then apparently follows the trend of the marble bedrock northward beneath Tioga stage glacial deposits for a distance of 1.8 miles under the ridge that separates White Chief basin from Eagle Creek basin. The tracers emerge in about 3.5 days at Tufa Spring. The trace unifies and doubles the extent of the karst system located along the western flank of Mineral King valley. The results suggest geomorphic and hydrologic continuity of the marble bedrock. A fault mapped by others as offsetting the marble is thus questionable. Published maps of the geology of the western margin of Mineral King valley require minor revision to depict the new cave system correctly. A caver connection remains to be demonstrated. This karst system was identified during the past two decades. In 1978, B.W. Rogers and J.C. Tinsley of the San Francisco Bay Chapter, NSS, used fluorescein dye to trace water from Eagle Creek Sink to Tufa Spring. This experiment established that the Eagle Valley drains via an unexplored karst system from south to north, and follows the marble bedrock along the western flank of Mineral King valley. In 1996, L. Schultz of CRF, wished to fulfill independent study requirements for W.B. White's ground water hydrology summer course at Westerm Kentucky University, and to complete a senior thesis at Sonoma State University. Tinsley and J. Despain, Cave Management Specialist at Sequoia and Kings Canyon National Parks, suggested that studying the White Chief karst would be ideal. CRF had recently initiated a mapping and inventory project for Mineral King caves. Schultz, Tinsley and Despain successfully repeated the 1978 Eagle Valley-Tufa Spring trace, and Schultz established baseline hydrochemistry, linkage, and travel times for ground water within the karst of White Chief Valley proper. Tinsley had mapped a linear array of small sinkholes that extended from lower White Chief Valley across an intervening ridge nearly one mile northward to Eagle Creek and Eagle Sink. This train of sinkholes suggested that a much more extensive alpine karst system lay hidden under late Pleistocene morainal deposits. By this time, snow was imminent at the elevation of nearly 10,000 feet. A late-season, rather desperate dye trace from White Chief Basin to Tufa Spring failed, presumably owing to insufficient dye, adsorptive losses in the soil in White Chief Basin, relatively high volumes of storage in the karst aquifer, and dilution of the signal owing to the large flow from Eagle Creek. In 1998, armed with 20/20 hindsight, Tinsley, B.F. Lyles, A. Wilson, Schultz, and S. Toprak used 8 pounds of fluorescein, charcoal, 10 pounds of sodium chloride, and a Campbell 21-X data logger, an electrical conductivity probe, and a thermistor to repeat the 1996 experiment when the entire discharge of White Chief Creek was flowing into the input sink. Although diluted, the salt pulse raised the conductivity measurably in Tufa Spring; Nick Crawford's laboratory in Bowling Green, KY, confirmed fluorescein at 800 parts per trillion. The salt pulse's transit time was 3.5 days. Bugs from Eagle Creek placed below Eagle Sink were negative at the late summer levels of discharge.
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