Water Level in Deep Well?

I had a deep well drilled years ago. I think the driller told me they went down 270 feet to an aquifer. It has a submersible pump. Where I live hurricanes are not uncommon and occasionally we've been without power for days, so I have a generator to power the pump during those times. I've been thinking about what to do if my generator failed and am wondering if I could hook up a manual pump (I think they're called pitcher pumps) to the well in that case. But I know they can't pull water from large depths (I think 30 feet is max). So my questions:

Am I correct to assume that the water level in my well is around 270 feet? Or does the water from an aquifer typically rise in the well to some other level, such as the level of the water table? If the level is too deep for a hand pump, any suggestions on how to manually retrieve water from the well?

Thanks!

With a 270' deep well, the water level could be at 260', or at 2'. That water level will make a big difference when figuring a hand pump.