Kootenai County has awarded a $4.7 million contract to Sommer Construction Inc., of Nampa, Idaho, to expand its Kootenai County Farm Landfill operation by 14 acres.

Roger Saterfiel, director of the county's solid waste department, says a highly competitive bidding environment resulted in savings for the work, which the county had estimated would cost about $5.3 million. In about two years, the county plans a second expansion, another about $5 million project that would prepare another 11 acres to function as part of the facility, giving it enough capacity until the year 2039, Saterfiel says.

The current project is expected to begin soon and to be completed by mid-October. During it, the contractor will get 14 acres ready to operate in addition to the 35-acre lined landfill. Kootenai County owns a total of about 600 acres at the site, which is located about 13 miles south of Coeur d'Alene on U.S. 95, he says.

The work will entail excavating about half a million cubic yards of soil there and laying a high-density thermoplastic liner where solid waste will be stored. The contractor also will add a leachate collection system for the new waste cell that will consist of a drainage layer of sand and piping above the liner. The system will collect liquid that leaches down through the landfill and will transport it to nearby lined ponds, where it will evaporate. A new 3.5 million gallon leachate pond will be developed in the project, Saterfiel says.

Additionally, the contractor will install piping to connect to the landfill's methane gas collection system. Saterfiel says methane from the landfill, which currently is produced at a rate of 750 cubic feet per minute, is used to aid in evaporating the leachate.

The rest of the methane gas is burned off in two smoke stacks, but Saterfiel says the county has been approached by several individuals about purchasing its excess methane for methane gas-to-energy projects. He says he's looking into such a project for the future.