This version of the story has some photos. Pretty nasty crack, and certainly cause for alarm but not "feet" wide - feet tall maybe, and several inches wide...
That looks like the kind of material that would definitely be unacceptable organics. It's going to rot away and leave voids in the soil leading to settlement.
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Reading between the lines, I would bet it was a larger pour of the main foundation or other elements, and OP was hoping there was enough left over for the hot tub slab and ran a little short.
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Ask whoever is telling you that, how does the 4" topping loam magically increase the infiltration rate of the underlying soil that receives the water?
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I think your original version is closer to the "standard of care" required for engineers, assuming the "consultants" you are contracting are for other engineering services. The 2nd version has more superlatives, like "high quality" and "best industry practices" that seem to exceed the usual...
Could it be the arc length of the bend they want? A 60 degree bend, but not bent so tightly so it has a larger radius and that's the arc length of the bend, perhaps.
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So, even if that were true, what about if the wind blows during construction before it's chilled ... or if the freezer is taken offline for repairs/renovation. Would you be ok with the roof lifting off then with your stamp on the design?
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Just when I thought this thread might finally die, it comes limping back to life. On the positive side, if BA keeps going even I (a lowly site civil) might be able to design a building by the end of this!
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