HOUSTON COUNTY, Minn. (WKBT) -

The Minnesota Department of Natural Resources has shut down the smallest silica sand mine in Houston County.

The DNR told the owners of the Erickson Mine they are operating within a mile of a trout stream, Ferndale Brook, which means they need a permit they don't currently have. But the county said the mine doesn't need the permit.

A 2013 Minnesota state statute says mines operating within a mile of a trout stream need to have a permit referred to as a trout stream setback permit. The statute also says, however, any mine that has been operational before May 2013 is grandfathered in.

The Erickson Mine has been operational since 1992, so Houston County officials said the mine doesn't need this permit.

"Back in April we sent Mr. Erickson a letter saying there is a new law, looks like you're within a mile of a trout stream, you need a permit," Minnesota DNR Water Regulation Unit Supervisor Tom Hovey said.

Houston County officials said the mine has held a conditional use permit for 22 years. That permit is reviewed every five years.

"We have done that since 1992 up to even the present," Houston County Environmental Services Director Rick Frank said.

County officials said the Erickson Mine has never been late to renew its permit. But this time the DNR said the county took too long to give the mine the OK, and the permit expired.

"This one happened [due] to, in our opinion, the conditional use permit had lapsed, in our opinion. So they did not have a valid permit on April 30, 2013," Hovey said.

Houston County officials argue, though, the permit was still active while the county board was looking into the new law.

"We looked at the trout stream setback legislation that was passed by the legislators in '13, and we had that reviewed legally by an attorney that is hired by the county, and when we took everything into consideration, the County Board and the Planning Commission passed it," Frank said.

Houston County Board of Commissioners Chair Teresa Walters said the DNR has the wrong information.

"We have his findings that his permit did not expire. It is not a new permit, so it does not need -- it is grandfathered in under the old, the conditional use permit for a construction sand mine," Walters said.

The DNR said the law is new and there are things that still need to be sorted out, but they feel that the mine's permit was not in effect when the new law went in place, so it is considered a new mine.

"Mr. Erickson did ask for it in a timely manner. I mean, he did ask for it before it expired, but the county didn't act on it until over a year later," Hovey said.

"The conditional use permit did not expire because they renewed it on time and we did not act on it until after legal advice," Walters said.

The Erickson Mine is being labeled as a frac-sand mine. However, it is not a frac-sand mine; it only deals with silica sand.

Houston County currently has a moratorium in place against any frac-sand mining that runs through March 2015.

The DNR, the mine owners and Houston County are all in contact right now, trying to work through the process.