A bucket connected with a hose to mower exhaust, cover the mound and start the mower. Pump the mound full of carbon monoxide.
Use flexible electric metal conduit and fittings. The threads are the same as the muffler hole threads on the mower.
FYI- they work as a pack/herd in coordination when many are crawling on their prey. When one decides to attack it sends out a theramone scent and that tells them all to bite at the same time.