Kinnickinnic Township Chair Jerry Olson said he was taken aback this week by a murmur about the possible encroachment of frac sand mining. The six-mile-square township north of River Falls is a guardian of one of the most prized trout streams in the Upper Midwest -- the Kinnickinnic River -- and the town board has never been formally approached by any company wanting to mine silica sand for sale to the oil and gas industry.

But at a Town Board meeting Sept. 3, Brian O'Connor of Preferred Sands of Minnesota said a delay by the township in developing a frac sand mining ordinance would prevent his company from starting to mine in the area as early as the spring of 2014, Olson said.

"It was very strange," said Olson, who noted that the company had not previously come forward with any plans. "It made me a little more worried about not having an ordinance in place."

A call left for O'Connor at the Preferred Sands mine and processing site in Woodbury, Minn., was not immediately returned.The Pennsylvania-based company also operates a frac sand mine in Blair, Wisc., that has been cited by the DNR for unsanctioned discharges of sediment into the surrounding watershed.

At the Sept. 3 meeting of the Kinnickinnic board, members approved a six-month extension to a frac sand moratorium that was set to expire soon. Olson said the extension was needed to finish the ordinance. As township chairman, he wants an ordinance that will protect the property rights of people who might want to mine sand without "trampling" the Kinnickinnic River and the rights of others in the county who cherish the area's rural ambiance.

"We're pretty sensitive about what gets washed into the Kinnickinnic," Olson said.