DNR lets cattle producer use manure tank in karst terrain

The Iowa Department of Natural Resources has decided to let a cattle producer continue to use an underground manure tank built in karst terrain without a permit, despite concerns a future leak could quickly contaminate groundwater in the Cedar River watershed.

Tim and Joe Johnson, owners of Johnson Brothers, a feeder calf operation in Mitchell County in north-central Iowa, have paid a $10,000 fine and recently provided the DNR with results of a January study of the tank and its surroundings, said Sheila Bly, an environmental specialist in the DNR’s Mason City field office.

The study by Matt Reisdorfer of Chosen Valley Testing showed the basin does not meet the standards for a concrete tank built in potential karst terrain for a facility with more than 500 animals — which Johnson Brothers had when they installed the tank.

However, borings near the tank did not show groundwater pooling, which indicates the tank likely wasn’t built below the groundwater table, Bly said.

The DNR cited the Johnsons in 2016 for applying manure on frozen ground and not having a manure management plan.

The producers put in the tank to have a place to store manure during the winter, but did not know they needed a permit, Tim Johnson told The Gazette in November.

A 2020 DNR consent order levying the $10,000 fine said the agency sent the Johnsons a letter in 2016 telling them they would need a permit for a new basin.

Johnson Bros Consent Order ... by Gazetteonline

Since the investigation started in 2019, the Johnsons have reduced the size of their operation to less than 500 animals, which is considered a small operation not subject to state regulation.

“At this time, the facility operates as a small animal-feeding operation,” Bly said in an email this week. “There is no evidence of a current or of a past discharge from the storage structure, nor is there any indication that the storage structure is leaking.”

Bly said the DNR will continue to monitor the facility, but because it’s a small operation, it is not on a regular inspection schedule.

“So it won’t necessarily be something we visit every year or every three years,” she said. “We’ll continue to check in periodically and will certainly respond to any allegations of a leak or any issue with that tank.”

The Sierra Club’s Iowa Chapter and other environmental groups have spoken about their concerns about animal confinements in karst terrain.

“Leakage from the structure into the soil and then into karst terrain may cause pollution of the shallow aquifer and wells that draw from the aquifer,” Steve Veysey, an Ames water quality advocate collaborating with the Sierra Club, told The Gazette in November.

“More and more shallow wells in northeast Iowa routinely measure high in nitrate (above the 10 parts per million limit) and often show levels of E. coli, which is very disturbing.”

Wally Taylor, who serves on the executive committee of the Sierra Club’s Iowa chapter, said he’s glad the DNR pursued enforcement action and a fine in the Johnson case.

Comments: (319) 339-3157; erin.jordan@thegazette.com