The drinking water treatment plant in McCook has been on-line for nearly two years, but the process to dispose of the waste from the plant wasn't resolved until April 8.

That's when the Nebraska Department of Environmental Quality approved the permit for McCook to operate a Class I non-hazardous waste injection well at the sewer treatment plant.

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The injection well operates by pumping the waste nearly 2,000 feet underground.

Waste from the water treatment plant is currently being diverted to the sewer.

David Miesback of the NDEQ told the McCook City Council Monday night that the process is a relatively new way to get rid of waste considered to be non-hazardous -- there's only one other site in Nebraska, in Crawford, that uses the method -- but geological conditions make McCook an ideal location.

The local underground source for drinking water is primarily shallow, Miesback said, at the most at 100 feet. Waste from the water treatment plant, containing nitrates, uranium and arsenic, will be pumped underground and dispersed from 1,826 to 1,880 feet, into a porous sandstone level called the Cedar Hills Formation.

The well is not much different than those used by the oil industry, he said, when water that is pumped up with oil is injected back underground.

Miesback told Councilman Lonnie Anderson that the well should last as long as the water treatment plant is operating.

"It's like your car -- if you maintain it, it should last a long time," he said, adding that the one in Crawford is going on 18 years old.

The injection well will begin to operate some time in mid to late summer, said Jesse Dutcher, McCook Utilities Director.

Bids for a small shed to enclose the injection well still have to be approved, along with computer controls that connect it to the water treatment plant, said Greg Wolford of W Design, who, with JHC Joint Venture completed and submitted the injection well permit application.

The injection well will be monitored daily through computerized controls in addition to an annual, week-long assessment when it will be shut down to be completely evaluated.

The well is equipped with various forms of safety features, Meisback said, including concrete to stainless steel casings to prevent any leakage, Additionally, a containment pond is nearby at the sewer treatment plant for the waste if the well ever needs to be shut down.

Waste from the water treatment plant that has been diverted to the sewer has caused problems with testing at the sewer treatment plant because of the high salt content, Dutcher said.

In order for the wastewater from the sewer to be considered safe to be released into the Republican River, it has to meet certain standards to ensure that the treated water is not harmful to animals, fish, insects or the environment, Dutcher said.

"Wet" tests, or whole-effluent toxicity tests, measure various aspects in water, with one phase recording how well water fleas live and reproduce. When the microscopic flea is placed into a sample of treated waste water from McCook, it survives but does not reproduce at an acceptable rate, Dutcher said, because the fleas are very sensitve to the chlorides found in the waste from the water treatment plant.

Although Texas has thousands of non-hazardous injection wells and Kansas several hundred, the concept is still new in Nebraska, Miesback said. As a result, McCook may lead the way for others who are considering the process.

"You're famous now, so everybody who wants one will be calling here," he joked.