Opponents of the Dakota Access Pipeline warned this would happen. They probably didn't expect it to come so soon, however.

The newly completed conduit, which cuts across a reservoir relied on by members of the Standing Rock Sioux Tribe, leaked 84 gallons of crude oil in South Dakota in early April, recent media reports indicate.

Members of the tribe, who fought hard to block part of the pipeline's construction, said the relatively small spill bolsters their argument that Dakota Access threatens their water supplies and livelihoods.

SEE ALSO: Dakota Access Pipeline protest movement now focuses on the money

The April 4 leak was cleaned up but not widely publicized at the time. However, it is only one in a string of mishaps facing the pipeline's builder, Energy Transfer Partners.

The Texas-based developer has racked up multiple air and water pollution violations throughout Ohio while building a major natural gas pipeline, the state's environmental regulators said.

The Ohio Environmental Protection Agency (OEPA) this week issued a $431,000 fine against the company, citing 18 incidents since late March that involved mud spills from drilling, stormwater pollution, and open burning.

OEPA pics of crews cleaning up spill that blanketed 6.5 acres of a protected wetland in NE Ohio with several million gallons of bentonite: pic.twitter.com/xNrMGt7dPU — Marion Renault (@MarionRenault) May 10, 2017

On Wednesday, federal officials ordered Energy Transfer to halt new drilling activity along the Rover pipeline until the company complies with new measures and receives authorization.

One spill affected a village's public water system. In April, a pipeline crew dumped around 2 million gallons of bentonite mud, which is used as a drilling lubricant, into two Ohio wetlands. Earlier this week, a 200-gallon mud spill created haphazard conditions in Harrison County.

"All told, our frustration is really high. We don’t think they're taking Ohio seriously," Craig Butler, the OEPA's director, told the Columbus Dispatch.

"Normally when we have ... a series of events like this, companies respond with a whole lot of contrition and whole lot of commitment," he said. "We haven’t seen that. It's pretty shocking."

A spokeswoman for Energy Transfer said the "small number of inadvertent releases of 'drilling mud'" aren't unusual during drilling operations.

"We do not believe that there will be any impact to the environment," she told the Dispatch.

Image: Ohio environmental protection agency

The $4.2 billion Rover pipeline to Michigan will carry natural gas from West Virginia, western Pennsylvania, and eastern Ohio.

Meanwhile, in South Dakota, tribal attorneys are pressing for further environmental studies of the $3.8 billion Dakota Access pipeline. The 1,170-mile conduit will carry oil from North Dakota through South Dakota and Iowa to a distribution point in Illinois.

Activists near the Standing Rock Sioux Reservation try to halt construction of the Dakota Access Pipeline outside Cannon Ball, North Dakota, on Dec. 6, 2016. Image: scott olson/Getty Images

Under the Obama administration, the U.S. Army Corps of Engineers had planned an additional environmental study before ruling on the project. But the Corps abandoned the idea after President Donald Trump pushed it to approve the pipeline shortly after taking office.

The pipeline is not yet fully operational but is expected to come online soon.