Douglas County commissioners Wednesday unanimously approved language that encourages agricultural industry businesses that locate near the Lawrence Municipal Airport to preserve the soil there.

They approved a slight change to the county’s major-planning document, Horizon 2020. Commissioner Nancy Thellman had asked commissioners to revisit the language when she took office in January. The issue has been a hot topic since 2007 when an industrial development proposal near the airport surfaced.

Neighbors and other opponents of the development plan had sought stricter language.

Thellman said Wednesday night that adding the soil conservation reference to the planning language represents a “baby step toward trying to point us in the direction of saving soil.” The county and city will still consider changes to the environmental chapter of the planning document.

City commissioners would still have to approve the changes for them to take effect.