Re: But PHall says a tunnel bypass is impossible, the ground too mentally unstable
Date: 12-01-2019 - 13:33
And, what's your source...? "Impossible I say, I say it's impossible by gosh and by golly...."
This isn't going to be easy. And, it will be very expensive. And, yes, there is unstable sedimentary geology all over this area, with lots of underground water permeating some of these formations, or "flowing" through it. There are plenty of places where the underlying "mudstone" still has not achieved the "stone" part. Why, do you think the bluffs are so unstable in this area?
Of course, we humans have actually done many tunnels here in the US, and around the world that have overcome unstable soil conditions and ground water issues quite successfully. a As, I liked to tell some of my clients, we have the technology to build almost anything you want, if you have enough money to throw at it. But, my job was to try to figure out if it would be worth it, or not...
That being said, I'll leave it to the numerous experts who are doing the alternatives studies to see what the problems are, and how much of an obstacle they present. I'll also leave it to the wealthy Nimby's down in Del Mar (like my wealthy Nimby "Freeway Fighters" in South Pasadena), and their lawyers, will also hire "experts' who, no matter what route, will be able to "prove" it is "impossible", once they are paid enough too... It's the world we live in...for better, and/or worse....
So, with your two cents worth of unsubstantiated "headline" claims of tunnel "impossibility", may I ask just how many geotechnical reports on rail or road project tunneling conditions you've had to read?