[en] The data contained herein are a compilation of hydrogeochemical information collected by the US Geological Survey and Sandia National Laboratories in support of the proposed WIPP facility. These data have been collected as a result of field operations ongoing since 1976 and are a result of extensive observations made at 24 locations. Hydraulic testing, chemical analysis, and geophysical logging have been performed in the water-bearing zones of the Rustler and Bell Canyon Formations. Transmissivities in these zones vary within nine orders of magnitude, and total dissolved solids range from a few thousand to 400,000 mg/L throughout the study area. The hydraulic data, for the most part, represent confined water-bearing horizons that range from stratigraphic contacts to 30 ft in thickness. Due to the low productivity, these zones would not be classified as aquifers anywhere else in the world. Wells within a 2-mi radius of the site and in the general SE direction of flow of the dominant aquifer in the Rustler (the Culebra Dolomite) yield no more than 0.2 gal/min over an extended period of pumping