EPA gives up hope of filling Oronogo pit

ORONOGO, Mo. — Four years ago, officials with the Environmental Protection Agency didn't think they'd have any problem filling the Oronogo Circle.

The goal was to take mine waste from the region and deposit it into the 12-acre mine pit that decades earlier had filled with water, and then cap it, leaving behind an open, grass field.

It's what happened to the much smaller water-filled mine pit known as Sucker Flats in Webb City’s King Jack Park. It took more than two years and 2 million cubic yards of rock, dirt, chat and other mining waste, but fill it did. Mark Doolan, the remedial project manager for the EPA supervising the cleanup of the Oronogo-Duenweg Mining Belt Superfund site, said they capped it with clay and topsoil and the end result is 20 acres of new parkland.

That's not been the case in Oronogo.

The pit, known variously over the years as Oronogo Circle, Big Blue and Blue Hole, was closed in 1948. Over the years it developed into a lake with depths at least 200 feet in some places.

Doolan said in 2012 that he didn't think they'd have any trouble filling the pit, estimating then that it would hold 4 million cubic yards of mine waste.

“We have 7 million cubic yards of waste across the county that needs to be hauled somewhere,’’ he said in 2012. “There is more than enough waste to completely fill the pit.’’

But after years of dumping mine waste into it — 2.5 million cubic yards so far, Doolan said — the mine pit shows no sign of filling.

Doolan said truckload after truckload of mine waste dumped into the pit have had no visual effect.

“You can’t even tell if we’ve put anything in it,” he said.

The EPA is using mine openings as repositories for the waste rock, known as chat. The waste is contaminated with heavy metals — lead, zinc and cadmium — that can be hazardous to human health and the environment. Once cleared, the scarred land can then be used, but there are restrictions, such as prohibitions on sinking shallow wells.

Doolan thinks that one reason the pit is not filling as expected is because of the presence of a number of long, deep tunnels at its bottom. The extreme depth of the hole also could play a role in the pit not filling as expected.

Although Doolan noted that the EPA has not put a boat into the lake to test its depth, he said hopes of being able to ever fill it with mine waste have dropped.

More mine waste, he said, "is not going to make a difference.”

With just one more piece of property on the north side of Oronogo to be cleared, Doolan said the EPA’s dumping of waste into the pit is just about complete.

He said cleanup efforts continue in other areas of the historic mining belt, but it wouldn’t make financial sense to haul mine waste back to the Oronogo pit.

What happens to property after the EPA is finished with it, Doolan said, will be up to John and Regina Mueller, who own land on which the Oronogo Circle is located.

For more than 30 years the couple operated a recreation park and scuba dive shop known called Captain John’s Sports and Scuba at the pit.

Under the Muellers' ownership the pit was renamed the Blue Water Recreation Park and Scuba School and became a local place for divers to train, because the pit had visibility of up to 50 feet. The Muellers added a 12-foot indoor pool, sunken platforms and several underwater features for divers to explore.

As part of the agreement with the EPA, the former mining company that originally owned the pit, also reached a financial settlement with the Muellers for the loss of their business.

Now that the EPA is close to returning the mine pit to the couple, John Mueller said he and his wife have no interest in restarting their business.

“I’m 70 years old,” he said. “I’m not planning on doing anything with it.”

Mueller said that in order to reopen his business he would have to try to contact former customers who likely have found other dive spots to use and try to convince them to return to Oronogo.

“It would be like starting a brand-new business,” he said.

Mueller also said that while he and his wife did receive a financial settlement for the loss of their business, they feel they weren’t completely compensated for true value of the company.

“They took out a 36-year business,” he added.

Mueller also said the he knew that, given the depth of the lake and the type of material that was going into it, the EPA would have trouble filling the pit.

“It wasn’t going to happen,” he said. “And now it just sits there.”

Mueller said once the EPA turns the mine pit back over to them that they will likely look to sell the property.

Quality question

The question of whether it was environmentally safe to put millions of cubic yards of mining waste into water-filled pit was explored by earlier tests near Waco.

In 2006, the Environmental Protection Agency, in cooperation with the Missouri Department of Natural Resources, placed 58,500 cubic yards of mine waste into a mine pit near Waco, then covered it with a soil and clay cap. Three monitoring wells were drilled around the pit to check for changes in groundwater quality.

According to Mark Doolan, project manager for the EPA supervising the cleanup of the Oronogo-Duenweg Mining Belt Superfund site, the test caused a short-term release of zinc into the groundwater. After 30 to 60 days, the release had diminished to a negligible amount. Doolan also said the removal of the mining waste from the surface eliminates contaminated runoff into local streams and rivers.