Did you know that if you own property in the Rocky Mountain region, chances are your ownership stops just under the top layer of dust? And God help you if Chevron thinks there is oil or gas under that dust. In Colorado most subsurface mineral rights are federally owned and it is unlikely you will be able to stop anyone from fracking under you to get them.
In 1916, Congress passed the Stock Raising Homestead Act by which the federal government retained the mineral rights under huge tracts of western lands. They figured that settlers, farmers and ranchers didn’t need them and mineral exploration was beginning to escalate.
Fast-forwarding a century finds us with horizontal drilling and hydraulic fracturing and a nation of new concerns.
Fracking wells are drilled vertically a mile or so deep, well below the water table, then they turn 90 degrees and continue horizontally for thousands more feet. Several radial arms are drilled horizontally from the one main vertical shaft. These radial arms are lined with steel pipes, then explosive charges are sent down to blow holes along the length of all the horizontal piping. Once the pipes are perforated, an average of 3 million gallons of water is pumped down the bore. If you have trouble visualizing that amount of water, think of a line of 200 tanker trucks.
This water is pumped down the well by huge, semi-trailer-sized hydraulic pumps exerting pressures around 7,500 pounds per square inch, cracking and pulverizing the rock shelves and ledges deep underground. Sand is injected to keep the cracks from closing, allowing oil or more often, natural gas to seep through the cracks where it is extracted.
About half the water that is pumped down these wells is recaptured; no one can say with certainty what happens to the other half. The recaptured water is contaminated with acids, formaldehyde and a brew of miscellaneous hydrocarbons. This “backflow” water is either pumped into settling ponds and allowed to evaporate or pumped back down nearby dry wells. Natural gas is a relatively clean energy source but the extraction process is certainly the dirtiest and possibly the most dangerous that the world has ever experienced.
Proponents say fracking is perfectly safe, after all it’s been around since 194. That’s quite true but the last nine years have been markedly different. Technological advances in oil extraction have ushered in horizontal drilling and incredibly new depths and reaches. So there really isn’t a lot of history to judge by but there is growing concern about the safety of the process.
The US Geological Survey researched earthquake rates in the hard-fracked area around Oklahoma City. From 1975 to 2008 there were one to three 3.0 magnitude earthquakes per year. From 2009 through 2013 the average grew to 40 per year including a swarm of earthquakes in 2011 that was capped by a damaging 5.6 magnitude event. They concluded that the increase was related to wastewater disposal from gas and oil activities. See http://www.usgs.gov/newsroom/article.asp?ID=3710.
Earthquakes have also increased dramatically in the eastern and central US. The past four years saw nearly 450 seismic events of magnitude 3.0 and larger compared to an average of 20 per year from 1970 to 2000. USGS scientists found that the increase in seismicity coincides with the injection of wastewater in deep disposal wells.
Pulverizing the earth beneath our feet and then lubricating it with fracking fluids may be allowing settlement of natural voids and causing rock shelves and underground ledges to crumble and slide past each other, revealing this subsidence as earthquakes at the surface.
Moneyed interests and oil lobbyists are spending lavishly to assure us that fracking is safe but only time will tell.