ST. CLAIRSVILLE - A longwall mining operation under Airport Road outside St. Clairsville has resulted in some road irregularities. According to the county engineer's office, the result will be a drop of three-to-four feet during a span of three-to-four days. The miner was run a distance of 800 feet. The width is about 10 feet. Because the longwall mine passed beneath a road, there are buckles in the pavement as a result.