Environmental concerns are motivating much of the opposition to A.F. Gelhar Co.’s proposed sand mine in the town of Union.
Among the concerns are the mine’s potential impact on air quality due to dust from the operation and its impact on local groundwater due to a high-capacity well, and a nearby stream due to stormwater runoff from the mine.
The Sierra Club urged the Union Town Board to vote against the proposal, due in part to the mine’s potential impact on local water resources.
“The installation of a high-capacity well could also threaten water quantity in an area where resources are limited and facing substantial pressure from other types of development,” the Sierra Club noted in a Sept, 18 press release.
Before any sand mine opens in Wisconsin, it must receive several permits from the county, state and federal level.
In this, the second of a series on the sand mine proposal, the County Post will examine the proposed mine’s high-capacity well.
Sand mine water usage compared
to ag irrigation
Gelhar plans to install a high-capacity well that will draw 500,000 gallons per day, according to Steven Sorenson, an attorney and spokesman for A.F. Gelhar.
“We probably won’t get close to that,” Sorenson said.
The water is used to wash the sand after it has been extracted from the ground.
Mike Koles, with the University of Wisconsin Extension office in Waupaca County, compared the amount of water that Gelhar plans to draw to the amount drawn by area farmers who use high-capacity wells to irrigate their crops.
The Wisconsin Department of Natural Resources has issued 20 permits for high-capacity well for farms in Waupaca County. Those farms are permitted to use over 9 million gallons per day under normal conditions with a maximum usage of 18.3 million gallons per day.
A single farm in the town of Dayton can draw between 1.44 million and 2.88 million gallons per day.
“It seems like a lot of water, but it’s not when you compare it to agriculture,” Koles said, regarding Gelhar’s high-capacity well permit.
Thomas Woletz is a senior manager with the state DNR who oversees the permitting process for sand mines.
Prior to the DNR issuing a permit for a high-capacity well, hydrologists review the permeability of the local soil and the depth of the groundwater. From this information, they construct a “cone of depression” model that shows how groundwater levels will be affected in the area.
Depending on the projected impact, the DNR may set more stringent conditions regarding the well’s location, its capacity and construction.
Woletz also compared the amount of water used in agriculture to what would be used in the sand mine.
“The amount of water used by ag high-capacity wells absolutely dwarfs what is used by a sand mine,” Woletz said.
He also noted that sand mines return more water to the aquifer than irrigated farms.
“There is some loss through evaporation from the washing ponds and some loss through the drying process, but about 80 percent of the water used by a sand mine will be returned to the water shed,” Woletz said.
“We’ve made a pledge to the town that if we interfered with anybody’s well we would replace it,” Sorenson said.
In an Aug. 27 memorandum regarding wells, Gelhar has agreed to maintain a well recovery and replacement program for any existing well within 2,000 feet of the mine site.
The agreement entails that Gelhar pay for an independent contractor to test the production and draw down of the wells in order to set a base line. If any private wells that experience a significant decline in water production, Gelhar would be responsible for repairing or replacing the well system.
Changes to the memorandum are among the conditions the Union town Board has sent to the Waupaca County Zoning Committee regarding the mine.
The town is seeking to expand the radius for well testing from 2,000 to 3,000 feet.
“If problems occur with water tests in the mine, then Gelhar must retest surrounding wells within a 5,000-foot radius of the mine quarry,” the town’s proposed conditions state.
Koles said the zoning committee, should it decide to grant Gelhar a conditional use permit for the sand mine, may want to include a pump test to determine the local cone of depression.
“You can’t really know the specific, local situation until you take the pump test,” Koles said. “It will measure the water level when the high-capacity well is actually running.”
He said cones of depression are a normal occurrence around the high-capacity wells used to provide municipal water. As an example, Koles described how aquifer levels drop rapidly in the morning as a large number of people get ready for work, take showers, make coffee, all at about the same time. The effect, however, is temporary.
The next article in the series will examine the chemicals used in the sand mining process and how they may impact local water resources.