Environmental risks associated with flowback and produced waters in shale gas projects

Forecasting concentrations of organic chemicals in the vadose zone caused by spills of hydraulic fracturing wastewater

“…However, information from existing exploitations can serve as guides. Here we estimated the expected concentrations of pollutants in the storage tank on the basis of: the forecasting volume of return water, calculated using the values coming from an experimental database [Hayes, 2009] adjusting according an empirical expression [Ma, 2018]; and the contaminant concentration in this water, calculated by a predictive model which assess their evolution that has been adjusted from experimental data [Ma et al, 2018]. This information is very useful in the first management phases of the return waters, and will serve as a basis for further design of safety plans that include the monitoring and development of mitigation measures.…”

“…Based on the experimental data of volumes (Table 1 at 1, 5, 14 and 90 days) from the horizontal wells [Hayes, 2009], an empirical expression for modelling the evolution of the volume of return water is given in Eq. (3) [Ma, 2018]…”