Locating Salinity Sources In West Texas With Airborne And Ground-Based Geophysical Methods And Gis

Salinization of soil, surface water, and ground water is a chronic environmental and<br>agricultural concern in the southwestern U.S. In this study of a 91 km2 area near Ballinger in<br>Runnels County, Texas, we used a geographic information system (GIS) to integrate results from<br>airborne and ground-based geophysical surveys, water and soil sampling, and chemical analyses<br>to locate areas of brine concentration and determine their origin. Potential salinity sources in this<br>area are (a) subsurface brine moving upward along natural conduits (faults, fractures, joints, and<br>permeable stratigraphic units), (b) brine migrating downward from surface disposal pits,<br>(c) leaking oil and gas wells, and (d) evaporating shallow ground water as a result of agricultural<br>landscaping. A prime goal of the study was to determine the effectiveness of the method in<br>distinguishing potentially leaking wells from other salinity sources.