Sandi, do as ddrueckh says. It isn't as big of a job to remove the valve. Be sure you have a big enough container. Just slowly remove those bolts. Raise your trailer safely and as high as possible to make it easier. You might have to empty the container a few times. Let us know what made the valve stick. If the seal was stuck it still would open to a certain extend. A dry/wet vacuum would probably work to take most of it out the tank.
Tugboat95; seems cutting this and that is poor advise
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