Sci-fi Plutonium storage

Concept design of plutonium storage for upcoming Sci fi browser game. Client left me freedom in design process, and put in info only that prop will be for storing plutonium, and that it needs to be futuristic (sci fi) oriented, since game will take place 150 years from now in future, and it will be set on different planet - alien planet with hostile environment very much resembling planet Mars from our Solar system.

Since this building/prop is for storing PLUTONIUM, and since it is very radioactive and dangerous chemical element, I've put additional protection from radiation. Because of that storage has 2 doors, one very heavy horizontal (square one), and other smaller round one (round hatch), plutonium is stored under ground, for additional protection...

If you like this design, be welcome to check my other design from same project.