Thursday, 20 June 2013 00:00
I read with interest about the panel discussion on the pros and cons of so-called “hydrofracking.” The debate as framed makes good points, however, it also misses a few key points.
When I was an exploration and development geologist for a Fortune 100 oil and gas company, for all the majors I worked with the preferred industry standard practice for both oil and gas well completions was called an “acid frac,” or an “acid job.” Based on my understanding, this is still the preferred method for non-horizontal wells, not hydrofracking.
The acids pumped into these wells, such as hydrofluoric and hydrochloric acid, are highly concentrated to “clean out” or dissolve rock and natural cements to produce preferential flow paths for oil and gas. These old practices involve hundreds of thousands of U.S. wells—more than are typically hydrofracked. These practices are unregulated, as are the drilling muds.
“Mud” is a misleading term. These muds are laden with polymers, chemicals, and heavy metals formulated to bring to the surface crushed rock, coat the borehole, and prevent blowouts. My company experienced a “blowout” in Oklahoma that blew the entire drill string out of the hole when it encountered an over-pressured gas zone and the mud was not thick enough to counter the massive pressure. Muds are excluded from reporting, regulation or oversight.
The key to a successful well is the completion method: the type of mud used and how the well casing is cemented into place. The blow-out of BP’s Deep Water Horizon Anaconda well in the Gulf is a recent case of questionable cementing practices. There was also a major blowout several years prior in Ohio.
Well-drilling and completions are not regulated, left up to what is termed “best professional practice.” Yet large areas and groundwater zones in many old producing areas in the U.S. are contaminated from prior practices. This calls for a broad-based effort by citizens and government to reduce deaths and injuries. Despite best practices, accidents do happen.