When EPA’s long-awaited draft assessment on fracking and drinking water supplies was released, the oil and gas industry triumphantly focused on a headline-making sentence: “We did not find evidence of widespread, systemic impacts on drinking water resources in the United States.”

But for fracking’s backers, a sense of victory may prove to be fleeting.

EPA’s draft assessment made one thing clear: fracking has repeatedly contaminated drinking water supplies (a fact that the industry has long aggressively denied).

Indeed, the federal government’s recognition that fracking can contaminate drinking water supplies may prove to have opened the floodgates, especially since EPA called attention to major gaps in the official record, due in part to gag orders for landowners who settle contamination claims and in part because there simply hasn’t been enough testing to know how widespread problems have become.

And although it’s been less than a month since EPA’s draft assessment was released, the evidence on fracking’s impacts has continued to roll in.

A study in Texas’ Barnett shale found high levels of pollutants – volatile organic compounds, heavy metals, and known carcinogens – in many people’s drinking water, based on testing from over 500 water wells. The contaminants found were associated with the shale drilling industry, but the researchers cautioned it was too soon to say whether the industry actually caused the contamination.

But the association was strong, the researchers said. “In the counties where there is more unconventional oil and gas development, the chemicals are worse,” lead researcher Zachariah Hildenbrand told Inside Climate News. “They’re in water in higher concentrations and more prevalent among the wells. As you get away from the drilling, water quality gets better. There’s no doubt about it.”

Those who might have hoped that EPA’s national study would help resolve questions swirling around fracking were largely disappointed, saying that EPA’s new draft assessment is largely a review of the current literature. EPA also heavily relied on data that was self-reported by drillers to FracFocus or to various states, leaving open questions about whether the accident rates they found are in fact under-stated.

Historically, the executive summary from EPA’s assessments on the oil and gas industry has provided a much rosier picture than the details included in the body of the report. And a close look at EPA’s new draft assessment reveals some striking results that haven’t made headlines.

EPA couldn’t say with certainty how many fracked wells there are in the US, nor could it say how much wastewater was produced from fracking. They could say that overall, the oil and gas industry is producing billions of gallons of wastewater a day – hundreds of billions of gallons per year – but couldn’t say how much of that was tied to fracking.

Roughly a third of America’s newly fracked wells that EPA could find were drilled in densely populated areas – either metropolitan areas or what the EPA calls “micropolitan” centers, where over ten thousand people live close together (p. 109).

Wells have been fracked as little as 0.01 miles away from a public drinking water supply, which supplies homes that do not use well water (p. 111) But despite how close fracking is to people’s homes and public drinking water supplies, the EPA admitted it knows shockingly little about how risky the chemicals used are to human health (p. 38).

Meanwhile, accidents keep on happening, both above-ground and under, by the hundreds or thousands. One in a dozen spills by drillers wasn’t contained before it hit drinking water sources – and the spills that hit water supplies tended to be much larger spills than those that didn’t (p. 38). Although gas wells are generally depicted as having numerous layers of concrete and steel casings to prevent the gas, wastewater and chemicals inside the well from interacting with the environment outside it, two thirds of wells had no cement along some portions of their bores (p. 275), an EPA review found. And conditions underground, which can leave wells under high pressure, high temperatures or in “corrosive environments” sometimes caused well casings to have “life expectancies” that run out in under a decade (p. 281) – but the oil and gas industry has told investors that shale wells are expected to keep pumping for 30 years or more.

Here’s a look at more of the evidence that’s buried in the fine print on the EPA’s study.

First and foremost, fracked wells can contaminate underground drinking water supplies and there are multiple documented cases where that has occurred. The EPA’s assessment, for example, concluded that in Pennsylvania, “in some cases, the methane [found in drinking water wells] appears to have originated from deeper layers such as those where the Marcellus Shale is found.” The agency also cited cases of water contamination tied to the Vermejo coalbeds in Colorado’s Raton basin. (See p. 284-5 of the report). 

In fact, at the five sites EPA selected for its retrospective studies, they found problems everywhere and most of the time, the only available explanation was fracking. An aquifer was contaminated with wastewater and tert-butyl alcohol in North Dakota and EPA concluded that the only possible cause was a blow-out during fracking; in Northeastern PA, where gas is often naturally found in water supplies, 9 out of the 36 wells EPA analyzed were newly contaminated due to fracking activities (25%); salty groundwater contamination in Southwestern PA likely came from a fracking wastewater pit; in two of the drinking wells EPA studied in Wise County, TX, the only explanation consistent with the EPA found contamination was brines from fracked rock layers and a third drinking well may have also been similarly polluted; and in Raton Basin, CO, EPA found pollution but couldn’t “definitively” link it to the coalbed fracking done in the area.

The agency also cited examples of lesser-known problems elsewhere in the US. For example, “[i]n Bainbridge, Ohio, inadequately cemented casing in a hydraulically fractured well contributed to the buildup of natural gas and high pressures along the outside of a production well,” EPA said (p. 40-41). “This ultimately resulted in movement of natural gas into local drinking water aquifers.”

At least 12.2 million people live or drink water from within a mile of a fracked well, but that is almost certainly an under-count because EPA couldn’t locate all the wells that were fracked. (p. 31-32; 116) Tens of thousands of new wells are drilled and fracked every year, EPA found, and half of the states in the country have now been fracked. So even if problems occur a small percent of the time, vast numbers of individual people could be impacted.

And companies have been allowed to frack using over a thousand different chemicals nationwide even though scientists have a very poor understanding of the ways that they affect people (p. 176). Little is known about the human health effects for the vast majority of the chemicals used in fracking, a problem that EPA labeled “a significant data gap for hazard identification.” The risks of long-term exposure were not know for 92% of the chemicals used during fracking (p. 38). Much also remains unknown about the health risks associated with 38-48 percent of the naturally-occurring materials that get mixed in with injected fluids underground, though more is known about these than the chemicals deliberately used by drillers.

The few chemicals whose health risks have been studied can have severe impacts on people’s bodies, causing cancer, kidney, brain and liver problems, and pose harm to developing fetuses and babies (though EPA cautioned that so little is known about the more commonly used chemicals that it wasn’t clear what risks an average well might pose) (p. 39).

This means that people whose health is harmed could have a hard time tying their ailments to fracking in court, because the science has lagged so far behind. It also makes it hard for regulators to know what chemicals are riskier or how best to prevent people from getting sick.

Although the oil and gas industry often focuses on “best practices” in describing how the modern shale rush has used emerging technology, even basic precautions are not routinely taken. Roughly 3 percent of fracked wells in one part of North Dakota – in other words, hundreds of wells per year – were deliberately built short on the well casings that are designed to protect drinking water supplies. And without enough casing, the risk of contamination spikes 1,000- fold, EPA noted (p. 39).

Much has been made of the long distances that fracking chemicals would have to travel to move from shale layers buried sometimes thousands of feet below the surface to the depths that people’s drinking water wells reach. But it turns out that twenty percent of fracked wells are considered “shallow,” which means that fracking happens much closer to drinking water supplies, EPA found (p. 41).

And, in a practice that has gotten very little attention, drilling companies are sometimes deliberately fracking directly into drinking water supplies. “The practice of injecting fracturing fluids into a formation that also contains a drinking water resource directly affects the quality of that water, since some of the fluid likely remains in the formation following hydraulic fracturing,” EPA wrote. “Hydraulic fracturing in a drinking water resource is a concern in the short-term (should there be people currently using these zones as a drinking water supply) and the long-term (if drought or other conditions necessitate the future use of these zones for drinking water” (p. 41).

Of course, it’s not just problems underground that cause contamination.

No one knows how much wastewater from fracking is produced nationwide, EPA reported, because states don’t consistently track the industry’s waste. This means there is no reliable way of knowing what percentage of wastewater winds up injected, dumped, spilled, deliberately evaporated in evaporation ponds, sent to treatment plants, sprayed on roads, or otherwise handled or mishandled. The amount of wastewater from a given well can be millions of gallons – sometimes even more than companies pumped in, or sometimes up to 90 percent of what’s inject remains below ground, EPA said.

Sewage treatment plants cannot handle fracking wastewater, and there is no evidence proving that commercial wastewater treatment plants can handle it either (p. 46).

Hundreds or thousands of chemical or wastewater spills can be expected annually, and an average spill is over 400 gallons (picture eight 50-gallon drums), EPA found, despite limited reporting. About one in ten spills reached surface waters, and nearly two thirds soaked into the ground. “These spills tended to be of greater volume than spills that did not reach a water body,” EPA noted (p.45).

Unlined wastewater storage pits can create “plumes” in underground water supplies, when fluids seep down through the soil into aquifers, and those plumes can create problems for a very long time and even reach nearby lakes, rivers or streams, EPA reported (p. 45).

And as droughts extend across much of the U.S., the sheer amount of water consumed by fracking – often permanently removed from the water cycle – also impacts America’s drinking water supplies. In some counties, fracking consumes more than half of all the water that is used annually, based on the industry’s own self-reporting, EPA noted (p. 35).
Problems underground have also dogged the fracking industry, and evidence is growing despite the complex and expensive technical problems that confront investigators into specific incidents.

Modern fracking techniques, where 10 or more wells are drilled from the same pad, may increase the risks of groundwater contamination, EPA found. In some parts of Oklahoma, fractures from two different wells accidentally crossed each other nearly half of the time. When this happens, fluids pumped down into one well can erupt out of a different well, causing fracking-fluid spills at ground-level (p. 42).

These risks are especially high if one of the over 1 million wells that were drilled and abandoned “prior to a formal regulatory structure” turns out to have been nearby (but that’s hard to anticipate because “the status and location of many of these wells are unknown” (p. 42).

About 1,380 wells over a decade old were fracked in 2009 and 2010, despite concerns that older wells were not tested to withstand modern fracking techniques. “The EPA estimated that 6% of 23,000 oil and gas production wells were drilled more than 10 years before being hydraulically fractured in 2009 or 2010. Although new wells can be designed to withstand the stresses associated with hydraulic fracturing operations, older wells may not have been built or tested to the same specifications and their reuse for this purpose could be of concern. Moreover, aging and use of the well can contribute to casing degradation, which can be accelerated by exposure to corrosive chemicals, such as hydrogen sulfide, carbonic acid, and brines.” (p. 41)

While all of this shows EPA‘s baseline for talking about fracking’s impacts, there are many reasons to believe that the agency’s numbers represent just the tip of the iceberg. In its executive summary, EPA acknowledged that its numbers “may be an underestimate as a result of several factors,” citing a lack of available data (p. 50).

EPA‘s study also took a narrow approach and left out many issues related to fracking, including problems that emerge during drilling or constructing well pads (even at sites where fracking is necessary to get the well to begin producing oil and gas), the impacts of mining of sand used as proppant, and what happens to wells once they stop producing oil and gas and are abandoned. Early plans to study air emissions and other effects were also dropped.

And of course, since the assessment is only a draft, it is still open for public comment. Public meetings and teleconferences to discuss EPA‘s findings are scheduled for this fall.

Photo Credit: Paper, Stack, Paperwork, via Shutterstock.