A questions for any structural engineers

[Fishward]

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I don't really see how, being that it is actually resting on the retaining wall in the middle of the room, that there could be any movement at all really.
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I trust the retaining wall, what i dont trust is 2 2x10s at a 6 ft span holding up 3000lbs.

http://www.awc.org/calculators/span/...rcalcstyle.asp

at 100 psf (pounds per square foor) this calc says your max span is 10ft. you've got 4 times that....