My sump is completely sealed (covered and caulked.) I believe it was probably done as part of a Radon remediation system installed by a previous owner.

Right now, as we speak, the crazy northeastern storm has the water level about 4" from the top of the sump hole; to my knowledge, my sump pump had never even turned on before this past weekend. It's fighting gamely to keep up, having run continuously for the last four days, and it just might squeak through, but it has me very nervous.

What's most bothersome is that the sealed sump:

(a) makes it impossible to toss in a secondary pump just in an emergency situation, like now. I bought a little submersible pump at HD that I was going to throw in just to give the sump pump a little help if the water levels got any higher, but I'd have to cut a ton of caulk to get in there, and wouldn't be confident I could do the whole thing without disturbing the existing pump, and right now that is the last thing I'd want to do.

(b) If my pump fails, it's going to be hard to effect any sort of quick repair. I mean, it's possible obviously, but it's going to be a lot harder than I would like.

Is there a reasonable way to deal with a totally sealed sump hole? Should I get the cover removed and replaced with something less draconian? In a Radon-remediated basement, is it hopeless to ever really have easy access to the sump pump? Should I just install a back-up pump, re-install the cover, and hope that's good enough?

I'm trying to figure out a reasonable approach here; even if I make it through this particular storm intact, I'd like to be in a better position to deal with future situations. Any input would be appreciated.