U.S. EPA has made available a draft discussion text from the Science Advisory Board’s (SAB) review of EPA’s Draft Hydraulic Fracturing Study Plan. The SAB report, while still a discussion draft, makes clear that in the SAB’s view, the major risks to drinking water resources posed by hydraulic fracturing are from flowback water and produced water, and that these need to be more carefully defined and studied.

Flowback waters are those that come back up the wellbore during well construction. Produced waters are those that come back up the wellbore when the well is producing.

The SAB also highlights the difficulties of creating a national regulatory structure when actual practices and their results will be determined by differences in local geology, and the local availability of water and wastewater disposal facilities.

The SAB report supports EPA’s plan to analyze fracking fluid constituents by using existing databases of these constituents, rather than engaging in additional toxicity analyses.  The report takes approving note of the newly established FracFocus Chemical Disclosure Registry website (see separate blog entry). The SAB report urges EPA to consider not only the likely constituents present in the fracking fluids and formation waters, but also disinfection byproducts from drinking water treatment systems.