Waste injection wells: The Earth’s invisible dump, With more than 30 trillion gallons of toxic waste having been injected into the inner earth, what happens if our belief that what goes down can’t come up is wrong? by Jefferson Dodge and Joel Dyer, September 20, 2012, Boulder Weekly
April 10, 1967, was no ordinary day in Boulder County. What started out like any other spring morning quickly became anything but, as buildings began to shake and the sound of broken glass filled the air. Firsthand accounts describe how people poured from buildings onto the streets looking bewildered by what they had just felt. Children were sent home from area schools because brick walls had cracked and were feared unstable. Many suspected there had been some type of explosion, but in reality, Boulder and the rest of the Denver metro area had been hit by an even rarer event, an earthquake measuring 5.0 on the Richter scale. Earthquakes are an oddity in Boulder, but the tremor would turn out to be the least bizarre part of the story. The real kicker, which would not come to light until years later, was that the whole affair was self-inflicted. The shaking of the Front Range had been the result of a man-made, or at least man-caused, earthquake with implications that are profound for all of us today and future generations as well.
Like previous decades, the 1960s were a nightmare for the environment. Toxic waste from chemical, pharmaceutical and other dirty manufacturing processes were still, for the most part, being dumped directly onto the land or into our waterways with both impunity and disastrous consequences. … The bottom line from the decade of free love is that Americans woke up and got fed up with the toxic dumping that was taking place in full sight of anyone willing to look, and as a result of the backlash of this new movement, industry after industry started to get the message that “the times they were a-changin’.”
But what were polluters to do with all of that toxic waste? One part of the answer was obvious; it had to be gotten out of sight and thereby out of mind. The rest of the equation proved to be a little trickier to solve.
But in 1961, the federal government, by way of the U.S. Army, found a way to make its toxic waste seemingly vanish from the landscape and the public’s scrutiny. Many industries would subsequently follow the government’s lead. The Army decided to borrow a technique that the oil industry had been using since the 1930s to get rid of the excess water it produced as a byproduct of oil and gas extraction. It decided to inject the worst of its toxic chemical waste being stored at the Rocky Mountain Arsenal in Commerce City deep into the Earth as a means of permanent storage. The Army drilled a 12,045-footdeep well and started pumping its waste liquids into the permeable rock layer at that depth. The toxic brew, which consisted of everything from pesticides to nerve gas to rocket fuel, was being injected into the new disposal well under great pressure. Most folks think of rock as solid and impenetrable, but sandstones, shales and limestones are actually porous and contain fractures that allow for the entrapment and even the flow of liquids. With enough pressure behind it, that flow can be increased so that millions of gallons of liquid waste can be forced into such formations. In March of 1962 the Army started injecting toxic waste into the well. What happened next was unexpected. On April 24, 1962, at the Cecil H. Green Geophysical Observatory at Bergen Park, an earthquake measuring 1.5 on the Richter scale was recorded with an epicenter in the area of the arsenal, where such events were unheard of previously, and it wouldn’t be the last such mysterious shaking in that area. By the end of that year, 190 earthquakes centered under or around the arsenal had been recorded. All of the quakes were very small until Dec. 4, 1962, when a moderate quake hit, causing structural damage to homes in Irondale, a small enclave located on the northwest edge of the arsenal. By the time it was all said and done, more than 1,300 quakes would rock the area between 1963 and 1967, three large enough to cause damage to buildings. The 5.0 earthquake that rocked Boulder in 1967 was followed a few weeks later by what is still the largest quake to ever hit the Front Range since at least the late 1800s, a 5.3 shaker that was felt from Goodland, Kan., all the way to Laramie, Wyo.
While most people, even those at the U.S. Geological Survey, were puzzled by these earthquake phenomena, the Army was not. They had been tracking and studying the earthquakes in association with their waste disposal well, particularly the pressure and volumes being injected. The Army wasn’t sure how exactly it was causing the quakes, but it did understand that its disposal well was the source of the tremors. As a result, it stopped using the well for disposal to bring an end to the quakes. But while the earthquake activity slowed, it didn’t completely subside until the Army actually reduced the pressure in the well by pumping out some of its waste. The Rocky Mountain Arsenal disposal well experiment laid the groundwork for how polluting corporations could get rid of their toxic waste going forward, and uncovered one of the problems that could eventually spell disaster for U.S. drinking water supplies. And it’s not the potential for earthquakes that poses the biggest risk for future water contamination. The tremors are only a symptom of a much larger problem: The rock formations that we are counting on to hold our most dangerous toxic waste forever are actually full of faults and fractures that have never been mapped and that could allow some of that waste to escape upward into our underground aquifers.
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 of the well. 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.
It has been assumed for decades that all of the deadly toxic waste that has been and continues to be injected into deep formations will never be able to migrate back up to the shallower groundwater aquifers that provide us with most of our drinking water. It has been assumed by everyone from polluting-industry representatives to the Environmental Protection Agency (EPA) that the layer of rock being injected with waste and those layers above the injection zone form a perfect barrier that will always prevent upward migration into groundwater aquifers. But as is often the case when humans do things with the expectation of “always and forever,” new information has a nasty habit of changing the equation. And using the inner earth as a giant toxic dump is starting to look like no exception to the rule, as new research is beginning to cast doubt on our long-held assumption that what goes down can’t come back up. This is bad news, considering the tens of trillions of gallons of deadly toxins that are already swimming around beneath our feet. [Emphasis added]
[Refer also to: Halcyon hot springs vanish after B.C. quake ]