The Coast Guard says it is continuing its response to the grounded towing vessel 'Kimberly Selvick' in Lake Michigan off of Burnahm Park.The vessel remains partially submerged, while the two barges that broke free from the tug Monday afternoon have been removed and towed to Calumet Harbor Fleeting. The vessel began taking on water and became partially submerged while trying to retrieve the two barges. Four people aboard the tug were evacuated by a rescue crew from the Chicago Fire Department Marine Unit. No injuries were reported. An overflight of the area revealed a 10-foot by 100-foot sheen near the vessel. Initial inspections indicated that the sheen was caused by small quantities of residual oil waste from the tug’s bilge and not from fuel onboard.