The US Environmental Protection Agency said it has analyzed water samples from four shale plays across the country, but released no test results or preliminary conclusions Friday when it issued a progress report on its investigation of the effects of hydraulic fracturing on drinking water.
Commissioned by a Democratically-controlled Congress in 2010, EPA's investigation is studying the impacts of fracking on drinking water through the entire "life-cycle" of water use in shale oil and shale gas extraction, from its acquisition and withdrawal through injection via fracking to its disposal.
Friday's progress report outlined the 18 separate research projects -- including five local studies -- that EPA is conducting with regards to fracking and drinking water but gave no indication as to what its investigation may have found thus far.
"Information presented as part of this report cannot be used to draw conclusions about the potential impacts to drinking water resources from hydraulic fracturing," the EPA said.
The EPA did note two major modifications to the study from its original design. The first is the inclusion of data from FracFocus, the voluntary fracturing database set up by the Groundwater Protection Council, the Interstate Oil & Gas Commission and the oil and gas industry. EPA said that in many cases FracFocus' data is more accurate geographically and more up-to-date on the chemicals being used.
The EPA also decided not to investigate the phenomena of naturally occurring radioactive materials being unearthed by high pressure fracking and traveling to the surface. That activity is already being investigated by the US Department of Energy and several universities, EPA said, and the agency will rely on those studies to reach any conclusions.
EPA noted in its progress report that it had completed two rounds of water sampling and was preparing to undertake a third in the coming year before it issues a final report in 2014.
In addition to the sampling, EPA said it was running computer simulations of how rock fractures to determine if fracking can contaminate shallow aquifers or open lines of communication between the deeper well bores and shallower water aquifers.
Four of the five locations for water sampling are in shale plays: Dunn County, North Dakota (Bakken); Wise County, Texas (Barnett), and Bradford and Washington Counties, Pennsylvania (Marcellus).
All four were chosen because the location saw a well blowout that leaked fracking fluids or because of homeowner complaints that the quality of the water from their drinking water wells had declined.
A fifth location, Colorado's Las Animas and Huerfano counties, is in the Raton Basin coalbed methane play.
