Down a dirt road in northwest Oklahoma, only a few hundred yards from where the city of Enid draws its drinking water, a company injects the toxic byproduct of oil production deep underground.

That close proximity violates a state rule meant to protect public groundwater supplies from oil field wastewater, which can be saltier than the sea and laden with toxic metals. Injection operations are banned within a half-mile of public water wells unless regulators hold a hearing to ensure that such activity will not pollute the water.

But in 2018, without a hearing, state regulators approved this injection well, an apparatus that applies pressure to dispose of wastewater down a steel tube. And in the years since, the well, named the Flying Monkey, has repeatedly failed structural integrity tests, signaling a potential leak.

The Frontier and ProPublica mapped every injection well in the state to determine how close they are to public water wells. We identified at least 114 injection wells in communities across Oklahoma — including the Flying Monkey and two others in Enid — that are located within a half-mile of a public water supply well. More than 300,000 Oklahomans live in communities that rely on these water wells, according to our analysis.

Does your Oklahoma water system have oil field wastewater wells near public drinking water wells?

Search for your address, ZIP code or water system name to see how many oil field disposal wells are within a half-mile of a drinking water well.

Examples: 120 W Maine St, Enid, OK 73701, Seminole, 73160

Your location is not within a water system that has disposal wells near public water wells.

These public water districts have oil field disposal wells near drinking water wells.

Sources: Oklahoma Corporation Commission, Oklahoma Department of Environmental Quality, Oklahoma Water Resources Board

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