I'm no expert but I've been around a lot of concrete pours. NO WAY I would put a loaded truck across that dam and I wouldn't think a sober driver would either. 150yrds is about the max on a big inline pump I believe. Plus your slump is gonna suck to push it at that distance. You really don't have good options if you are set on that site. I'm not sure I would trust the dam widened with dirt alone. It would make me too nervous to even try. You may need to piggy back 2 pumps to keep a good slump. Set one up one the truck side and another one the house build sight. This would keep the pressure up on the pumps. Another feasible option might be to use and inline pump to get the mix across the dam to a backhoe bucket. This would be more efficient than using GA buggies. I have poured many hard to reach places with a backhoe. Just some ideas that I didn't see mentioned. Keep us posted if you start this project this will be interesting. Good luck

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