Increasing drilling and hydraulic fracturing (with associated water demand) in the Eagle Ford Shale is occurring during a time of drought, adding to concerns with this added demand for water.  In this work, two alternatives to the use of fresh water in hydraulic fracturing operations will be investigated.  First, the feasibility of using desalination concentrate (from brackish groundwater and flowback water treatment) as hydraulic fracturing fluid will be assessed by performing geochemical modeling analysis.  Second, the feasibility of using nanoparticle-stabilized CO2 foam as a fracturing fluid will be investigated.  In this effort the feasibility assessment will focus on 1) generating a stable CO2 foam using brackish groundwater desalination concentrate and nanoscale silica particles, 2) evaluating the rheological properties of the CO2 foam as an alternative hydraulic fracturing fluid, and 3) development of a preliminary hydraulic fracturing treatment process using nanoparticle-stabilized  CO2 foam, including determination of proppant and foam schedules.