WASHINGTON — For almost as long as there have been oil wells in Texas, drillers have pumped the vast quantities of brackish wastewater that surfaces with the oil into underground wells thousands of feet beneath the earth’s surface.

But with concern growing that the underlying geology in the Permian Basin and other shale plays are reaching capacity for disposal wells, the Trump administration is examining whether to adjust decades-old federal clean water regulations to allow drillers to discharge wastewater directly into rivers and streams from which communities draw their water supplies.

Technically speaking, drillers are allowed to do this in limited circumstances under federal law, but the process of cleaning salt-, heavy metal- and chemical-laden wastewater to the point it would meet state or federal water standards is so costly that it’s rarely done, experts say.

“Technology is changing. At some point, if your disposal options are limited or it becomes so expensive you’re having to truck water to be disposed of several hundred miles away, companies will do it,” said Jared Craighead, legal counsel to Texas Railroad Commissioner Ryan Sitton. “It might not make sense today but maybe in a year or two.”

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The Environmental Protection Agency is consulting with experts and conducting public meetings around the country toward making a decision next summer, said Lee Forsgren, deputy assistant administrator at EPA’s Office of Water, Tuesday in Washington. “We’re very much in a listening mode now,” he said.

The primary question facing the EPA is whether water standards can be adjusted so oil and gas companies can economically treat wastewater to be pumped into the water supply without contaminating drinking water supplies or killing off local wildlife.

In 2016, the EPA banned municipal sewage plants from accepting wastewater associated with hydraulic fracturing after it was discovered that in Pennsylvania, water was sent to plants not equipped to properly clean it. Amid that state’s fracking boom, residents along the Monongahela River in western Pennsylvania were advised to use bottled drinking water.

“It would be so difficult to (treat the wastewater) because there’s so much we don’t know,” said Nichole Saunders, an attorney with the Environmental Defense Fund in Austin. “There’s only a handful of research papers. We don’t have approved testing methods. The complicating factor here is there’s not really the science and data to inform EPA.”

In Washington, lobbyists for the oil and wastewater industries are pushing hard to loosen regulations they say go too far. Their primary case to the EPA is that the treated wastewater could provide a valuable resource for drought-ravaged water supplies in the western United States, with potential uses for agriculture and industry, and even drinking water supplies.

“It’s an opportunity that could have some really good benefits, particularly in areas that need water,” said Lee Fuller, executive vice president of the Independent Petroleum Association of America. “At this point all that water is just going back in the ground.”

A Texas-sized problem

The Texas oil industry also faces a looming crisis. As the shale drilling boom has grown, so has the problem of what to do with the huge volumes of wastewater. A rule of thumb is that for every barrel of oil, four or five barrels of wastewater are produced.

In earlier times, drillers would pump the water right back into the same field. But they have struggled to do so in shale fields, which have tighter geology than conventional oil fields, forcing operators to send their water to off-site disposal wells, Fuller said.

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As drilling activity in the Permian Basin has intensified in recent years, officials at the Texas Railroad Commission — which regulates the state’s oil and gas industry — have begun to hear concerns in Upton and Reagan counties in West Texas about pressure in disposal wells building to high levels from overuse. At the same time, a series of small earthquakes in the area has raised concerns that West Texas could succumb to the same earthquake problems that have plagued oil fields in Oklahoma and North Texas, which scientists have linked to underground wastewater disposal.

“Because of over-pressurization and concerns about seismicity, we are limited where we can permit injection wells,” in the Permian Basin, said Craighead, the Railroad Commission official.

Treating wastewater and then pumping it into rivers or selling it to farmers to irrigate fields would provide a much needed alternative. For now, the technology still can’t treat drilling wastewater economically —but that could change soon. In El Paso, for example, the city’s water utility is running a desalinization plant to treat brackish water with a salt content similar to oil wastewater to produce up to 27.5 million gallons of fresh water daily.

“What will really reduce the timeline is if (the EPA) actually comes up with discharge standards and gives people an incentive to develop these technologies,” said Leonard Levine, technical director at Gulf Coast Authority, an agency that operates wastewater treatment plants around Houston and West Texas. “Never underestimate the ability of the oil and gas industry to develop technology quickly.”

An eye on Horizon

Over the next six months, oil companies will push to make their case to an EPA that under President Donald Trump has proved friendly to the oil and gas sector. Last month, the EPA proposed loosening Obama-era regulations around methane leaks from pipelines and drilling sites. The Department of Interior is also in the process of rewriting safety standards for offshore drilling put in place following the 2010 explosion of the Deepwater Horizon drilling rig in the Gulf of Mexico.

“If this study is not done correctly and they don’t put the proper treatments in place, it would be a major step backward,” said Andrew Grinberg, special projects manager with the environmental group Clean Water Action. “The concern (is) that it is window dressing that will give them cover to weaken the rules.”

At the Railroad Commission, staff are looking into applying to the federal government for authority to administer wastewater discharge permits, something now done by the EPA. It would entail developing testing protocols and hiring more staff, something likely to catch the attention of budget hawks in Austin, but doing so would allow the state government to control the flow of water permits, taking the EPA out of the loop.

“We’re still in the very early stages, but this could be a good alternative,” Craighead said. “Almost every Permian operator has gotten more interested in this.”

james.osborne@chron.com

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