AUBURN — Efforts to lower Christian Hill and improve airplane approaches to the Auburn-Lewiston Municipal Airport may hinge on a new water quality permit.

K&K Excavation of Turner, which has operated a gravel mining operation at Christian Hill since 2000, is applying to the Maine Department of Environmental Protection to dig into southern Auburn’s groundwater table.

“We are right there at the groundwater table on one side of the quarry, even though we are on top of the hill,” planning consultant Mike Gotto said. “We are filing a permit to allow the operations to continue and to complete the project up there.”

Much of the land is owned by the airport and the cities of Lewiston and Auburn. Christian Hill is south of the airport between Foster Road and Route 122 and the hill has been an obstruction since it opened in 1935.

K&K has a contract with the airport to remove the top 50 feet of the hill, making the approach to the airport’s Runway 4 safer.

“The ultimate height varies as it goes across the mountain,” Gotto said. “It’s a glide slope across and we have to go something like another 20 or 30 feet on the lowest part. But there’s another large acreage that we still have 40 or 50 feet that need to be removed.”

Gotto said the water table rises as it goes up the hill.

“And it drops as the hill drops as well,” Gotto said. “So we are taking off the crown of the hill, and I don’t think there should be impact on anybody. But we are lowering the water table.”

Gotto and K&K hosted a public information session for neighbors on April 23. Many get their water supply from wells and neighbor Leo J. Binnette, 90, of 333 Foster Road, said his water quality has declined drastically this year.

“I have a deep well, 100 feet deep or so,” he said. His pump was set at 80 feet and he’s had dirty water since Christmas. “So I had them reset my pump and raise it to 40 feet but I still have dirt coming out,” he said.

Gotto said K&K will be testing neighborhood wells for quality.

“We’re going to address all the concerns we can, as we do this,” Gotto said.

He said he hopes to submit the permit application Monday.

Mark Stebbins, mining coordinator for the DEP, said the state will take about four months to evaluate the permit.

In the meantime, Gotto said K&K is avoiding the area near the water table.

“We are still excavating this year,” he said. “There is still quite a bit of area where we can excavate and we can avoid the area where the water table is.”

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