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EOG Resources plans to increase stormwater management for Cooks Valley sand mine

By LeAnn R. Ralph

CHIPPEWA FALLS — EOG Resources has filed an application to amend the non-metallic mining reclamation plan for the Dennis Schindler frac sand mine in Cooks Valley to add approximately 37 acres for stormwater management facilities.

A public informational meeting was held on the proposed permit modification June 3 at the Chippewa County Courthouse.

Following persistent problems with local runoff from the mine reported by neighbors last summer, a torrential rain on September 3, 2014, resulted in 18 Mile Creek through Colfax being polluted by colloidal clay runoff.

The sediment in the creek through Colfax became visible September 5, and 18 Mile Creek remained a thick caramel color for more than a week.

Jim Devlin, a wastewater specialist from the Baldwin office of the Wisconsin Department of Natural Resources, said he had walked through marshland to trace the sediment back to the Dennis Schindler mine operated by EOG Resources.

The DS sand mine is about five miles northeast of Colfax.

Retention ponds

Dan Masterpole of the Chippewa County land conservation office said the stormwater retention ponds at the sand mines are designed to start out dry, to fill up when it rains, to infiltrate into the ground before the next rain and then to fill up again.

The problem last year, Masterpole said, was that with the high amount of rainfall, the water did not have a chance to infiltrate into the ground from the stormwater retention ponds before the next rainfall occurred.

Clay in the runoff from the sand mines also eventually accumulates in the bottom of the retention ponds, sealing them off so they cannot drain.

From the DNR’s perspective, another part of the problem is that the general stormwater runoff permit available for DNR personnel to issue to the sand mines was intended for smaller sand and gravel operations and not for industrial frac sand mines.

Last year, many of the sand mines in Chippewa County experienced problems with colloidal clay runoff.

Chippewa County has about  3,000 acres permitted for sand mine reclamation.

All together, Wisconsin has more than 100 permitted or operational frac sand mines and processing facilities to produce sand for hydraulic fracturing used to extract oil and natural gas.

Johnson site

According to the proposed permit modification from EOG Resources, the 37 acres at what is known as the Johnson Site directly south of the DS mine will be used to provide additional stormwater management facilities to deal with runoff from the mine site.

According to the application, “the purpose of the proposed stormwater management facilities is to provide the operator with the ability to treat stormwater prior to discharging off the site to the local drainage ways and the waters of the state. The proposed amendment will provide additional capacity to treat and detain stormwater at the site to enable the operator to best perform stormwater Best Management Practices identified in the Storm Water Pollution Prevention Plan.”

Landowners within 660 feet of the Johnson Site include LA Property Acquisitions (Bloomer); David Wogernese (Eau Claire); Dennis Schindler (Bloomer); Paul and Vicki Freeberg (Colfax); Mark and Virginia Berge (Colfax).

The permit application notes that drainage from the Johnson Site is a tributary to an intermittent stream to the south. Running Valley Creek is classified by the Wisconsin Department of Natural Resources as a Class II trout stream, which flows into 18 Mile Creek, which discharges into the Red Cedar River at Colfax.

No wetlands were identified on the western part of the Johnson Site, and the proposed project will not have any wetland impacts. Hydrology will be maintained to identified wetlands through pond discharges and stormwater diversions, according to the permit modification application.


The post-mining land use at the Johnson Site will primarily be conservation land/wildlife habitat planted to establish a passively-managed native prairie and to preserve wetland wildlife habitat, according to the application.

The existing house and driveway at the site will remain during the mining operation and into post-mining.

Final reclamation at the Johnson Site will take place when the final reclamation has been completed at the DS mine site.

Critical areas, located within 75 feet of wetlands and streams or slopes, ditches and swales that drain directly to a wetland, river or stream will be fertilized with a phosphorus-free fertilizer, according to the application.

Phosphorus-free fertilizer is important for the Red Cedar Watershed to help reduce the amount of phosphorus runoff reaching Tainter Lake and Lake Menomin.

Phosphorus is one of the nutrients implicated in toxic blue-green algae blooms that occur in the lakes every summer.

The proposed permit modification from EOG Resources is intended to comply with the statewide non-metallic mining reclamation standards established by NR 135, Chippewa County non-metallic mine reclamation standards, and the Town of Cooks Valley non-metallic mining ordinance.