First off, I'm completely fascinated by the Mariana Trench, so I think it's great you wrote this. That said, it could use some work.
For example, there were some spelling and grammar errors. For one, don't refer to the Foundation as just "SCP" - call it "the Foundation" or "the SCP Foundation." Also, the name of the location is the "Challenger Deep," not the "Challengers Deep." There were also some minor errors, such as "may enter SCP-xxxx container," rather than "may enter SCP-xxxx's container," as well as questions of grammar which I personally would have changed:
"It stated it was a human male and that it hailed from Britain. The specimen has alleged to have been part of the original HMS Challenger which took sail in 1872. The subject then states[…]"
I would've written all that in the past sense, like so:
"It stated it was a human male and that it hailed from Britain. The specimen then alleged to have been part of the original HMS Challenger which took sail in 1872. The subject then stated[…]"
Et cetera. These are all nitpickings, of course - my major problem with your article is this: "Any interference with the project by SCP-xxxx will result in five minutes of direct light into its visor." Why? That's terrible. Remember the cold, not cruel rule. Obviously, SCP-xxxx has not exhibited any sign of the suit being dangerous, so why would they want to remove it? They've already contained SCP-xxxx. Of course they might want to remove the suit for research purposes; not, however, so much that they'd torture what has shown all signs of being a living, thinking being if they were denied.
That said, I think this is a solid concept which has a lot of potential. Of course, that might just be my fascination with the deeps speaking, but I'd love to see this hammered out into a high-quality SCP and posted on the site proper. Good work.