Drilling the Marcellus

There has been a great deal of misunderstanding about the potential for drilling gas wells in the Marcellus Shale, and the alleged dangers presented by produced fluids that are brought up out of the wells and have to be disposed or reused. I won't claim to be a geologist, but I understand that the Marcellus, like lots of shales, is rather tight, meaning gas doesn't travel far in it. To develop it properly, it's necessary to drill horizontally in the formation and fracture (frac) it, in this case by forcing in water and chemicals under pressure, so gas can move in the tiny fracture lines toward the well bore. Fracturing the Marellus usually takes lots of water, which can become contaminated with chlorides and other substances.

In Pennsylvania the DEP has allowed disposal (after treatment) of some of these frac fluids and produced fluids into state streams, causing high levels of total dissolved solids in streams like the Monongahela. WV, on the other hand, does not currently allow discharge of produced fluids into state streams. All produced fluids in WV are reused, land applied, or put into the subsurface beneath drinking water sources through UIC (underground injection control) wells. In other words, they aren't going to state streams. The City of Morgantown, among other political entities, is trying to impose more regulation on Marcellus Shale gas drillers to reduce TDS in the Monongahela River, even though gas drillers aren't contributing TDS to that or any other WV rivers.

The WV DEP is acting to protect water supplies from excessive withdrawals by drillers to use in the Marcellus wells, and is also watching where the produced fluids go when they're pulled out of the wells. A copy of the DEP's recent guidance to the industry is found here. If you want a different take on the story, Ken Ward's blog can be found here.