Weeks after the release of a peer-reviewed study that found methane is “ubiquitous” in the groundwater of Susquehanna County, Pa., a new U.S. Geological Survey (USGS) review shows this phenomenon isn’t limited to just one Pennsylvania county. In fact, the USGS examination lends further scientific credence to the fact that methane in the Commonwealth’s groundwater is a fairly widespread occurrence – even in areas without any Marcellus Shale gas wells.
The USGS study sampled 20 water wells in Sullivan County in an area that hasn’t seen any shale development. Their results were both alarming and enlightening. For those unfamiliar, Sullivan County is due south of Bradford County, which is the most heavily drilled county that sits atop the Marcellus Shale.
Specifically, 30 percent of the samples contained detectable levels of methane, and ten percent had levels above one milligram per liter (mg/L). In fact, measurements ranged as high as 51.1 mg/L. What’s more? The USGS researchers also conducted isotopic testing on the samples with the highest recorded methane levels, concluding that “the isotopic ratio values fell in the range for thermogenic (natural gas) source.” Such a finding appears to contradict Duke University’s previous research on methane in Pennsylvania groundwater which surmised that methane in groundwater was attributable to Marcellus Shale development. The Duke study alleged that the thermogenic origin of the methane suggested a link to gas wells – and yet the latest USGS findings showed thermogenic methane in pre-drill testing!
The USGS analysis also found the wells registering high levels of methane also had the highest concentrations of arsenic, boron, bromide, chloride, fluoride, lithium, molybendum, and sodium. If these contaminants sound familiar, they should. They, in addition to thermogenic methane, have been touted by anti-fracking activists as examples of “contamination” from shale development in nearby Susquehanna and Bradford counties. Is it possible that critics of hydraulic fracturing are peddling phony science?
Nor were those the only contaminants the USGS researchers found. The testing also uncovered concentrations of gross-alpha radiation and radon-220 that exceeded maximum contaminant levels (MCL) set by the U.S. Environmental Protection Agency. One sample tested for gross-alpha radiation at twice the level of EPA’s primary threshold, and 17 of the 20 wells sampled contained levels of radon-220 above EPA’s proposed MCL of 300 pCi/L.
As if methane, radiation and a host of other contaminants weren’t enough, the researchers also found that 20 percent of the samples exceeded EPA’s secondary MCL of 300 ug/L for iron. Manganese concentrations also exceeded EPA’s secondary MCL of 50 ug/L in 35 percent of the samples.
In sum: groundwater in Sullivan County, like so many counties in northeastern Pennsylvania, naturally contains methane, radon and a whole host of contaminants that have nothing do with Marcellus Shale development.