New Mexico Geological Society Annual Spring Meeting — Abstracts

Data has been compiled by TSWCD staff from a well sampling program analyzed by the New Mexico Bureau of Geology and Mineral Resources, and including information from the NM Environment Department and tests run by private companies for Subdivision reviews for Taos County. Contoured maps were prepared for 19 selected constituents. Anomalous concentrations are noted in a number of areas, including most of the known "hot springs" in Taos County. These anomalous concentrations, above background levels, are probably due to hot waters rising along deep seated faults and mixing with shallow groundwater. Analyses of perennial streams in the Taos Valley shows surprisingly high TDS, that is tapped by the acequia system in the south Taos valley. A specific example of these results is best exemplified by the fluoride map. The highest concentrations, exceeding EPA drinking standards, are at the Ponce de Leon Hot Springs, located along the eastern fault bordering the Miranda Canyon graben. Wells drilled for domestic water supply in the same area also produce warm waters, with elevated levels of fluoride. Other high concentrations of fluoride (and arsenic, chloride, etc.) are mapped along other faults in the valley. High concentrations of several ions have been tested in groundwater wells near the Pecos-Picuris system of faults south of the Rio Pueblo and north of the Picuris mountains. This developing area around the Taos Country Club golf course and UNM-Taos Klauer campus is where faults buried by Quaternary fan and valley alluvium connect from the surface-mapped four plus PecosPicuris system of the Picuris Mountains to the four plus Los Cordovas faults north of the Rio Pueblo.

Additional studies of water geochemistry and water level monitoring are being planned by the New Mexico Bureau of Geology and Mineral Resources and the Taos Soil and Water Conservation District.