how do i get rid of this masive elephant grass

I've not heard of elephant grass.
Do you have a picture ?

You'll need a wide-angle lens ! It reminds me of that French car advert....Takes my breath away....
Seriously though It sounds like one big problem, what was it grown for in the first place? If it's near your house/shed it could be a fire risk>

Miscanthus usually gets up to 10 feet high rather than 6 feet. I'm afraid you'll have to dig it out. I know that won't be easy, as it not only forms a large clump, but tends to put out runners, but either wait for the topgrowth to die back down, or chop it down, then get digging. Try to remove every piece of root, any you miss will probably grow again.
PS - re the height, you might have Miscanthus sinensis which does only get about 6 feet. Not much fun to dig out, but possible.

You aren't talking about CHONDROPETALUM elephantinum, although the 'miscanthus is commonly known as Elephant grass

Sounds horrendous....whatever it is.(: