Test-drilling, water-chemistry data, and isotopic data indicate that the water at Oak Spring originates as recharge from precipitation onto the Oak Spring area west of The Basin--the principal tourist area in the park--and possibly onto the fractured igneous rocks of the western Basin. Tritium activity of Oak Spring water indicates that the average age of the water is less than 14 years. Test drilling in the vicinity of Oak Spring has shown that Oak Spring issues from bedrock, the aquifer being a sand bed 5-feet thick. Test drilling near two sewage lagoons in The Basin area has shown that the alluvium and colluvium, on which the lagoons are located, is not saturated at and near the lagoons. Previous hypotheses suggested that seepage from the lagoons might pollute shallow ground water moving westward toward Window Pouroff, the only surface outlet of The Basin, in the direction of Oak Spring, Oak Spring, almost 2 miles downgradient of the lagoons, is the sole source of water for The Basin. The test borings completed in bedrock below the alluvium and colluvium are dry, which indicates that no substandal leakage from the lagoons is occurring and no contaminant plume is identifiable.
Additional publication details
USGS Numbered Series
Hydrogeology, geochemistry, and quality of water of The Basin and Oak Spring areas of the Chisos Mountains, Big Bend National Park, Texas
Water-Resources Investigations Report
U.S. Geological Survey ;
ESIC, Open-File Reports Section [distributor],