(Radio Iowa) – A large sinkhole south of Knoxville is growing. The sinkhole is in an area where coal was mined decades ago. Marion County officials closed a gravel road on Friday after being alerted to the hole, which was 30 feet in diameter and about 20 feet deep. County officials say the hole has grown wider, up to 40 feet in diameter.

Representatives from various county and state agencies met Wednesday to come up with a plan to determine what has caused the collapse and how to mitigate the damage.