After seven years of debate and delays, the Scott County Board denied a permit to a contentious gravel mine project on Tuesday, citing worries that it could lead to groundwater pollution.

“The primary focus was their concern about the long-term impacts on the water supply, on the aquifer,” said Gary Shelton, county administrator.

City staff also noted that the county’s comprehensive plan says projects must have adequate road access or a plan to create such access — and that the mine’s developer didn’t do so, despite the prediction of 110 daily truck trips.

The mine was proposed for a rural, 85-acre site in Sand Creek Township that lies on a flood plain and is near several wells.

A vocal and organized group of residents has rallied against the project for years and saw the decision as an environmental victory. Residents feared that as the gravel mine grew deeper it would fill with floodwater laced with agricultural runoff, and that water would seep into the aquifer that supplies drinking water.

Nearby Sand Creek often floods, the group says, and the Minnesota Pollution Control Agency (MPCA) says it’s an “impaired” waterway.

“I’m greatly relieved,” said Peggy Jo Dunnette, a township resident. “I’m happy the board thought about the permanent nature of this hole in the ground.”

Steve Hentges owns Jordan Gravel, the company that wanted to develop the site.

“Obviously he’s disappointed,” said Matt Duffy, Hentges’ attorney. “We have been working with the county for seven years to address the county’s questions.”

Shelton said the process was stalled by time extensions made at Hentges’ request.

Duffy said it took time and money to complete an environmental impact statement and get an MPCA permit — both County Board requirements. He added that it was unorthodox to require an MPCA permit before the county had approved the project.

The mine got the permit in April, and it appeared the project would go forward.

“We don’t believe that groundwater is going to be impacted due to floodwaters,” said Jeff Udd, a MPCA water quality supervisor. He said that gravel mines are relatively low-risk threats, and a network of wells would be checked for contamination every few months.

Nonetheless, four county commissioners voted against the project. Just one — Mike Beard — voted for it.

“This thing about the polluted water troubles me, the way this conversation has gone,” Beard said.

He said that despite claims that the proposed mine would be unique in the state, several gravel mines operate in the Minnesota River Valley that are in a flood plain and mine under the water table.

All human activity impacts the environment, and the “impaired” status of Sand Creek is just a label and doesn’t mean it is dangerous to the public, he said.