Is time an issue? If not, here's a thought. One of my neighbors has two dozers, each about equivalent to a Cat D4. One has a blade on front and short rippers on back. He uses the other to pull what he calls a "Carry All". This isn't the "carry all" we all usually refer to. It's a scraper-carrier like the ones they used in the old days before the paddle wheels were added to modern scrapers. It's slower and it has a capacity of only 5 cubic yards, but it surely works very well. He can fill the thing in less than a minute. Six years ago I had him move around 3000 yd. for me with it. He moved about 60 yd3/hr @ $65/hr. He only moved the soil about 450 ft. on average though. Once the soil is scooped, the transport is a bit slow. As Eddie mentioned, the distance is important. The paddle wheelers move a lot faster in transit than this thing does, and dump trucks even faster. I don't know whether or not you might be able to find a used one to purchase, tow it with your dozer, then resell it when done, but that might be worth a little checking into. You'd still need something else to pre-rip prior to each pass; you wouldn't want to keep changing back and forth on your dozer from rippers to carry-all. As to the slowness, maybe you could build one pad and while construction begins on that structure you could be building the second pad, doing them in sequence rather than concurrently. You could keep a smaller crew occupied for some time building one structure after another.
I realize there is a low probability this is what you'll wind up doing, but thought it worth mentioning just so you know about the possibility. Good luck whatever you decide to do.
