To get into fuel storage you have to travel back to the cargo bay and enter the G.U.T.S. and there will be a door that is not locked. There was a fire phantom and a few mimics. Once you repair the power, Brittany LaValley is on the floor right there and has the key card for the fuel bay, you’ll be able to access the storage room. Good loot 3 neuromods as well as other stuff.
The last treasure hunt number is right at the top of the grav shaft on the wall.
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