Brainerd officials are trying to figure out what's causing a hole in the ice of North Long Lake. The hole is about than 21 hundred feet long and 400 feet wide. It was first discovered last February and reappeared again this year when the rest of the lake froze over. Dick Beeson is president of the Thirty Lakes Watershed district. He says the district is sending divers into the hole later this week to conduct tests. He says the hole could have been caused by a minor earthquake that opened up a hot spot more than a mile below the water's surface: