From the keel? That is, in the hold where the locking bolt is?
Or is your leak in the rear holds where the volcano is located?
If the leak is in the front and it's the bolt itself, a coating of grease will most likely take care of it. If it's the strap, the bolt screws into then you will most likely have grind away the glass holding the strap then make the decision to replace or remove the strap. Many have removed the strap altogether, that will be up to you.
However your leak is in the rear it's most likely the bottom gudgeon, either needs tightening or resealed.