Nice job on the base. I would suggest that you differentiate the surfaces more clearly so they don't blend into one another visually. On the figure, I really like what you've done with the checkerboard pattern on the shinguard.
Nice work, I think it could have done with some browny dirty shades in the grey concrete walls/floor maybe even a bit of green like GW Anthonian Camoshade on the walls to tie it into the green of the marine. The reinforcing metal coming out of the walls is really cool, but there could maybe have been a few bits of it twisted and protruding from the floor. Overall its a good first attempt with cork as it doesn't obviously look like cork. Good job!