Hardware and Fasteners - Removing / Cutting Bolts from Concrete

I'm removing a diving board from a concrete deck. There are four bolts set in the concrete, with nuts that are approximately 1 inch in diameter, that hold the base of the diving board. I've tried to remove the nuts by using a 12" pipe wrench and hitting it with a hammer, but they don't budge. There's a little bit of rust (I'm in AZ), and over the last few days - I've tried liquid wrench and pb blaster (saturated the bolts and tapped with a hammer) - still not moving at all. I'm guessing that the board has been there for about 20 years or so. I don't need to save the nuts or bolts, and I planned on cutting the bolts flush with the concrete once I removed the nuts, but there's no space to cut below the nut. I've looked for a nut splitter, but the largest I could find was 3/4". Does anyone have any advice on how to remove the nuts?

The 3/4 figure probably refers to the bolts size it will work on not the diameter of the nut itself or what size wrench it uses.These are two different things.

Measure the diameter of the bolt itself within the nut for actual diameter.I suspect it is not larger than 3/4.Check the splitter,if it says it's for a 3/4 inch bolt or less that means bolt diameter not nut diameter.

Thanks for the reply. I double-checked, the splitters that I've seen reference a 3/4" outside hex size.

You'll probably have to rent or borrow an angle grinder and cut the nuts off then.

OK. I'll do that then. I just wanted to make sure I wasn't missing a more simple alternative. Thanks for your assistance!