Southeast Ohio Injection Wells Are Unlikely to Contaminate Aquifers, but Continuing High-Pressure Injection into Relatively Shallow and Often Fractured Devonian Shale and the Local Presence of Orphan and Abandoned Wells Can’t Rule It Out

     We know from examples from Texas that injected wastewater can pressure up, making it more likely to move horizontally out in the formation. It could also move upward if there was a route to do so, such as uncased or inadequately cased abandoned wells, or an extensive vertical fracture system. The Devonian Lower Huron Shale in Washington County, Ohio, is relatively shallow at 1900 to 2700 ft below sea level. That puts it at depths from the surface from about 2500 to about 3800 ft below the surface. That puts it about half a mile below freshwater aquifers on average. The Lower Huron Member of the Devonian Ohio Shale is the injection zone for several oil & gas wastewater injection wells in Western Washington County, which have migrated horizontally through the shale in a downdip direction, a few miles and up to 5 miles eastward. That migration is significantly further than modeling, which suggests migration of less than a mile over a longer time period. Higher injection pressures and higher volumes of water injected will increase the rate and distance of migration. 

     Below is a structure contour map from ODNR of the top of the Lower Huron member of the Ohio Shale in Washington County, Ohio, showing depth below sea level. 

     While the Devonian Shale is known to have a vertical natural fracture system, often known as a joint system, those joints are typically sealed with minerals and do not conduct fluids upward or downward. At a certain pressure, those vertical joints could potentially be reactivated, resulting in fluid migrating upward. However, I'm not sure there is any evidence of that having occurred, but there may be, as a 2020 ODNR investigation did say that there was evidence of migration out of the intended injection zone. There is evidence, however, of pressurized fluid leaking up an abandoned well in Veto Lake when it “blew out” in 2021. The well is less than a mile from the Redbird #4 injection well. That fluid was tagged chemically, so it is known that the injection wells are definitely the source. According to a local gas producer of Lower Huron wells, the injection wells flooded his wells, causing them to pressure up and produce water instead of the gas that was previously produced. If this can be proven, which I believe it can, I believe the well owner is entitled to compensation from the company injecting the wastewater. The local gas producer said that the pressure on his wells has continued to increase since 2019, when it was determined that injection water moved horizontally five miles to invade his gas-producing reservoir.

     The following statements are attributed to David Jeffery, a professor at Marietta College.

“The problem with these formations in southern Ohio is that they have very low porosity and permeability, especially these deep formations that are down below.”

“Some of the fractures are letting the toxic fluids travel upwards.”

“You’re trying to push more fluids into an area that is already under high pressure and already has non-compressible fluids in it,” Jeffery said.

“The problem is that there’s no room for the fluids down in that layer. This stuff is coming up through these fractures because that’s the easiest way out.”

     The Redbird #4 injection well was correctly identified by the ODNR investigation as the source of the brine flooding the gas producer’s wells. According to Bob Wilson, whose gas wells have been affected, he lost production in 50 of his wells at a rate of several per week. ODNR initially suspended injections at 6 of the 7 injection wells near the area of concern.   

     According to Buckeye Environmental Network, there are 17 injection wells in the county, and 8 have had serious issues. ODNR spokesperson Andy Chow noted:

“At the request of the ODNR Division of Oil and Gas Resources Management, operations have stopped at four class II disposal injection wells in Washington County,” Chow said.

“On July 1 and 2, the owners of the wells agreed to voluntarily cease operations after the division notified them that their class II disposal injection wells were suspected to be causing impacts to other nearby wells that produce oil and gas. … While the class II disposal injection wells are voluntarily shut down, the well owners and the division will work towards a plan to address the issues.”

“The division already applies consistent pressure monitoring and reporting standards to these wells,” Chow said. “The division is working on a contract to have a third-party consultant conduct a study of the private water wells near the impacted production wells in Washington County.”

     Thus, I would say ODNR is addressing the issue, and the wells should remain shut down. I think that other injection wells injecting into the Devonian Ohio Shale should also be scrutinized more heavily and shut down if deemed necessary. While I don’t believe aquifers such as those in Marrietta, which I believe are alluvial aquifers below the Ohio River, are in danger like others believe, I do think injections into the Devonian need to stop in the area due to the verified concerns. Wilson has said that his wells continue to increase in pressure and have accelerated that pressure increase since 2023. The reason for the acceleration is not clear, as theoretically they should have been dropping pressure since injection stopped. Is there brine from other injection wells migrating? Is there a barrier near his wells causing them to have continuing rising pressure? In any case, if there is no injection occurring that can migrate, there should be no issues in the future with other gas wells further away or with potential aquifer contamination. Clearly, the injection zone reservoir in the Lower Huron Shale in the area is not suited to long-term high-pressure fluid injection.

     As I noted in a 2023 post on the same issue, SE Ohio injection well wastewater migration, the ODNR stated:

“an Ohio shale injection zone poses a substantial risk” for migration.”

    

 

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‘The precipice of an emergency.’ Marietta residents worry drinking water could become contaminated. Megan Henry. Ohio Capital Journal. July 14, 2026. 'The precipice of an emergency.' Marietta residents worry drinking water could become contaminated. • Ohio Capital Journal