I work on the Mississippi river on the M/V Frank Rader. Ever so often the company schedules us for a dry dock. We are currently going in for the next month. We are replacing our wheels. The boat is 50ft wide by 160ft long and 50ft high so it's kinda neat to watch anyway. We usually clean out our slop tanks filled with used oil and grease. They need to get in our fuel tank also. I believe there is a good job here if you would like to know more I'd be more the glad to ive you full details. Thanks!!!