Injection rejection: How disposal drilling could backfire

As science catches up to oil and gas drilling, a disturbing picture is emerging

Photo by Joel Dyer

When it comes to the nation’s current natural gas boom, a couple of different strategies have emerged. The oil and gas industry strategy is to drill as many wells as quickly as possible, before oil and gas regulations become more strict and local governments figure out how to stop some drilling activities altogether. On the other hand, for anti-drilling and anti-fracking adherents, the game plan is to stall this tidal wave of rigs until the science regarding oil and gas extraction’s impact on human health and the environment has a chance to catch up to the drillers.

Some of the research that has been done recently reveals that injecting liquids into deep disposal wells at high pressure can and does cause earthquakes. Such disposal wells are used, in theory, for the permanent storage of many toxic liquids, from nerve gas to fracking fluid. And when combined with the results of other studies, this earthquake research paints a picture of a coming environmental and human health calamity that, if unchecked, could threaten our nation’s drinking water supplies within a century.

Many citizens opposed to fracking have been claiming that the process causes earthquakes. The industry continues to deny this claim, but the research on the earthquake issue shows that, without question, fracking can and does cause very small quakes. But in truth, many of the activists are a bit misinformed. Most of the larger earthquakes that are being felt and even causing damage in gas country are not the result of fracking but rather the industry’s use of disposal wells to get rid of its produced water and recovered fracking fluid containing on average 632 chemicals, including many that are carcinogenic.

When oil or gas is produced, the wells generate far more water than hydrocarbons, at least five times as much, on average. This “produced” water as it’s known is very salty, often radioactive and contains other contaminants such as hydrocarbons and fracking fluid. Depending on the water’s makeup, which varies area to area, the water can be toxic to aquatic animals if dumped into streams and can kill crops and destroy farmland for years if used for irrigation. Some farmland irrigated with this “produced water,” as it’s called, has been rendered effectively dead, unable to even grow grass for years after the tainted water is applied.

While it is possible to treat and then release produced water, the industry considers this expensive and usually opts to inject contaminated water into deep formations underground, claiming that the contamination is trapped forever, causing no harm. And it’s not just the oil and gas industry that uses the inner earth as a dump.

Chemical companies, manufacturers and other polluting industries have been injecting their contaminated liquids into disposal wells for decades. In fact, it was our government’s decision in the 1960s to use injection wells to get rid of the U.S. military’s deadly waste, including nerve gas at Denver’s Rocky Mountain Arsenal (RMA), which served as the original model for industry to start injecting its contamination underground as well.

As a result, according to a recent ProPublica investigation, more than 30 trillion gallons of the most toxic waste known to man has been injected into the inner Earth in the last 40 years or so.

While the RMA injection well served as the beginning of disposal well use by polluters, it also sparked the original research that proved that injecting liquids into deep rock formations at high pressure causes earthquakes. At one point, the arsenal’s disposal well was causing hundreds of quakes a year, some large enough to knock down walls 30 miles away and be felt as far away as Laramie, Wyo.

The federal government studied the RMA well for several years, intentionally causing quakes before finally shutting down the operation after pulling back liquids to relieve the pressure about 12,000 feet below the surface. The government then began to study the injection well/earthquake connection at another site.

Like the arsenal well, other deep disposal wells, including one on Colorado’s Western Slope, located 110 miles southwest of Grand Junction and known as the Paradox Valley Unit (PVU), have now been studied by the federal government for more than 25 years for their ability to trigger earthquakes. The PVU has triggered more than 4,000 quakes since 1990, and scientists can, to at least some degree, control the quakes’ size and frequency, or eliminate them altogether by adjusting the liquid injection rate and pressure. But the real breakthrough is in understanding how the injection wells cause earthquakes.

Scientists believe that injection wells cause earthquakes by forcing apart and lubricating already existing faults in the underground rock formation being injected. It has been described as something similar to an air hockey table, where the puck doesn’t slide until the air creates a space between the table’s surface and the puck. The only way for an injection well to cause an earthquake is for it to be located in close proximity to a fault.

For this reason, many states, including Colorado, require that disposal wells not be located near faults. Yet, despite this rule, there are hundreds of earthquakes happening around these wells, from Texas to Colorado to North Dakota to New York and Pennsylvania. It’s not that the law is being disregarded. The truth is that the rock formations that we have been pumping our contamination into are not the perfect barriers we have been led to believe.

The main threat exposed by the existence of these man-made quakes is not the tremors themselves but rather that unmapped, unknown faults and fissures exist in the very rock formations that we are counting on to protect us forever from some of the 30 trillion gallons of toxic waste we have pumped into the ground to save money on our contamination problems. The truth is, we have no idea when we drill a disposal well whether the rock could one day release those toxins upward towards the surface.

While it’s true that companies conduct pressure tests as a precaution, to find faults, it is not a perfect science and faulting problems may not be discovered for years or ever, for that matter. New high-pressure injections force the older contamination farther out into the formation, where natural escape routes like faults may exist relatively far from the location of the original pressure test.

A U.S. Geological Survey report says that the area east of the Rocky Mountains “is laced with known faults, but numerous smaller or deeply buried faults remain undetected. Even most of the known faults are poorly located at earthquake depths. Accordingly, few earthquakes east of the Rockies can be linked to named faults. … In most areas east of the Rockies, the best guide to earthquake hazards is the earthquakes themselves.”

Translation: The best geologists in the world can’t know that a fault exists thousands of feet below the surface until there is an earthquake that tips them off. So if contamination is escaping through a fault or crack without exerting enough pressure to cause a quake, we might never know it.

This potential for unknown and unmapped faults and fractures in rock formations also helps to explain the findings of the two new studies in the Marcellus shale of Pennsylvania, which discovered that salty brine water suspected of originating from the Marcellus shale formation at 15,000 feet is making its way upward and into groundwater aquifers. This is happening even in areas where there has been no gas drilling, which indicates that the liquid is finding naturally occurring pathways from which to make its escape from the deep rock that, theoretically, according to the toxic waste disposal industry and the EPA, should have been inescapable. The researchers who conducted the Marcellus study can’t say how long this upward migration of liquid takes, but they guess it could be anywhere from a few years to more than a century.

So the research on earthquakes from injection wells confirms that the inner earth is riddled with unknown faults, fissures and cracks that we can’t detect from the surface. And the findings of the research on the Marcellus shale study proves that liquids, even those from very deep formations, if given enough time, can eventually find an upward route through such geologic weaknesses and reach groundwater.

When taken together, this research means that, given enough time, the toxic waste being injected into deep rock formations for permanent storage could well find its way into our drinking water supply someday. And this is only one of the ways that contamination can escape from injections wells. The EPA, which is charged with inspecting injection wells, has found that thousands leak or are inadequately cased or cemented to the degree that the contamination can migrate to nearby oil and gas wells and escape or simply come up the outside of the disposal wells casing and enter groundwater formations that way.

Mario Salazar, an engineer who worked for the EPA for 25 years helping the agency monitor the nation’s 680,000 disposal wells, says the EPA’s underground injection program does not have enough funding to provide enough oversight and enforcement. He adds that even if contamination is detected, it’s difficult to assign blame and determine what caused the leak.

“There are very few people looking, and even if they were looking, it’s almost impossible to, first, find a contamination plume and, second, to attribute that contamination plume to a very specific resource,” he says. “A company can fight that forever, because there’s no way to determine if that [contamination] came directly from them or it came from somebody else, or it was present in the natural groundwater to start with. … When you’re about to lose maybe a billion dollars because you did something wrong, you’re going to fight it, especially now that corporations are people. … Injection wells could be significant in possibly destroying a lot of potable water, or contaminating a lot of potable water.”

Salazar says he believes that within a generation or two, most of our groundwater will be contaminated and that quite a few people will suffer. It’s a dire warning from a man in a position to know what he’s talking about.

There are other ways to deal with our nation’s toxic pollution than injecting it into the earth, but they are more expensive. Perhaps it’s time to pay up before its too late for all of us, our children and grandchildren.


Parts of this article originally appeared in Boulder Weekly. Jefferson Dodge contributed to this story.