Hello again, your last idea is the best. Talk to the contractor doing the house nearby about the engineering and permit issues he faced.
The city is not going to want to accept any verbal descriptions from you the owner, they will rely on your own simple (to scale) pencil sketches for simple work, such as $1,000 worth of plumbing in some cases, but will require an engineered drawing for this kind of extremely heavy foundation work.
If there is a problem and they are found to not be strictly enforcing the building code, the people involved could loose their job... so these can be quite cautious.
A structural/ civil engineering firm will have no trouble figuring it out...but it could easily result in a project that is not cost effective... one of the reasons for that, is that a structural engineer by some reports, and in some states, can be sued even after he dies and his estate made to cover the damages, which can be in the millions of dollars if anyone is killed.
Stay in touch, I will be interested in how this situation unfolds.
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