The Buffalo County Board voted 9-3 last night to extend by six months its moratorium against new applications for frac sand facilities. The Wisconsin county that borders the Mississippi River across from Winona put its moratorium in place almost seven months ago. It was set to expire Oct. 31.

The county's highest health official, Jen Rombalski, had been urging an extension over concerns that sand mining operations could increase particulates in the air, including silica dust that has been linked to silicosis and other negative health effects.

"There is no proof that air quality is not negatively impacted by industrial sand mining operations," Rombalski wrote in a county memo last month.

Buffalo County has approved six frac sand mines since July 14, 2011. The moratorium doesn't stop the county from acting on applications that were filed before the moratorium.

County Board Photo Courtesy Buffalo County