The Sierra Club, Hoosier Environmental Council and Conservation Law Center say the Vigo Sunna operation about 30 miles northeast of Evansville will threaten about 10 miles of streams near Patoka River National Wildlife Refuge.

Vigo is waiting for the US Army Corps of Engineers to issue its Section 303 Clean Water Act permit.

Sierra Club said the permit included dredging or filling 98,000 feet of streams, 28 acres of open water and seven acres of wetlands in Pike County.

Additionally, the groups have argued, the planned surface mine would neighbor the refuge, which was created to provide resting, feeding and nesting habitat for migratory birds, protect bottomland hardwood wetlands on the river and improve the river’s water quality.

“From toxic water contamination to the loss of local headwater streams, this coal mine could threaten wildlife, harm waterways and damage other natural resources both locally and downstream,” Sierra Club Indiana Beyond Coal campaign representative Jodi Perras said.

“It will be impossible to replace the natural streams, waterways, and wetlands that would be destroyed by this project.”

Hoosier Environmental Council senior policy director Tim Maloney said the proposed 1500-acre Vigo Sunna operation had the potential to harm water quality and put outdoor recreation activities in and near Patoka River at risk.

“It is essential that Vigo Sunna's application for a Clean Water Act permit provide sufficient information for a comprehensive study of the mine's likely impacts, and fully evaluates alternatives that would cause less environmental damage,” he said.

Vigo has not released public comment on the groups’ concerns.

The southeast Illinois and southwest Indiana-focused miner has six active operations, including Liberty, Friendsville, Red Brush West, Chili Pepper, Red Brush and Cypress Creek.