IF you've had one gasket affected by the fuel you'd be well advised to go through the rest of the system and verify there are no more. If someone's specified or supplied one gasket in the wrong material there may well be more.
If it does prove disintegration and no sign of dissolving I'd have no hesitation in using the fuel once it has been suitably filtered as there is no reason not to; standard aircraft-spec fuel filters are more than able to achieve that.
As said above, you'll need a suitably clean vessel large enough to hold it all while the tank and system is cleaned out. Eight or nine of those metal framed metre-cube iso-tanks is just the thing and can't be too costly - probably good as a throw-away afterwards solution. You'll need a transfer system with an inline filter to get it all back into your main tank afterwards of course, and a decent spillage on deck would probably cost you more in harbour clean-up fees that just scrapping the lot.
Frankly by the time you'd set all this up it might just be cheaper and quicker to scrap the fuel and pay the disposal costs. I imagine an operation like yours can easily afford that.
Last edited by noflynomore; 10th Nov 2016 at 17:01.