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> Details of the 35.3-mile system, which emerged recently in a 505-page draft environmental assessment, reveals a design that fails to meet several key national safety standards. The underground system appears to lack sufficient emergency exits, ignore the latest engineering practices and proposes passenger escape ladders that one fire safety professor calls “the definition of insanity.”
I see. Use new tech to build a tunnel a new way and suddenly it must be bad because it not designed the same way as the old systems.

I hope your vacuum tubes don't burn out in your computer.

You really want to go in an underground tunnel miles long without emergency escapes.....?
Boring Co uses old tech to build a tunnel the same way its been built for decades...but smaller...
That is the future of tunneling. If we had tech that could dig tunnels the size of a big tube this would be quite a big advancement. Shrinking the equipment seems to be one way forward for tunnel digging.
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Big tunnels are more expensive because more dirt needs moving, the tunnel walls need to be thicker, and the tunnelling machine needs to be bigger and more powerful.
I'm not sure if this comment is supposed to be satire or not?

Boring Co is using a second-hand sewer tunnel boring machine. This isn't the future of tunneling, it's quite literally the distant past.

Modern mass transit uses bigger tunnels because bigger tunnels means more throughput. It's generally cheaper to dig two (parallel) big tunnels than a dozen smaller ones, since the fixed costs are such a large part of the expense.

This is the part that Elon doesn't understand: it's not all about opex. Capex matters to, and for infrastructure projects, capex dominates opex. (For example, if he hadn't wasted a billion on the dreadnought, i.e., capex, Tesla wouldn't be in the doldrums right now unable to fund its basic operating activities, i.e., opex.)

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This concept is not new at all, From what I understand the tunnel sizes proposed are barely bigger than the London Underground "tube" tunnels. (Glasgow's subway has even smaller tunnels too). Now, don't get me wrong, it worked quite well for London, but it's not exactly innovative.
Civil engineering has different, higher, standards for quality than software or even electrical engineering.
Quote is a criticism of a different bid, that they didn't get. Perhaps they've addressed some of these issues, and hence got the money?
That's a quote about an entirely different project that hasn't been approved yet. This 1 mile tunnel is much much less ambitious and probably is more about TBC building up expertise than actually deploying any fantastic new tech.
IIRC TBC never announced any "fantastic new tech", in spite of the marketing effort. It seems they have COTS tunneling equipment, a knack for ignoring basic establish practices, and a enthusiastic PR team.
Also, the whirling blades that move randomly up and down the length of the tunnel seem downright unnecessary.
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it's just an underground tram. it has 3 stops in a mile. there is no way (and no benefit) that the tunnel is evacuated, hyperloop-style, at those short distances.

which makes sense given the cost. which even at $50MM I very much doubt they can do it that cheap. the stations or other parts of it must be paid for in another budget.