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ANF gives approval to rail tunnel
The California High-Speed Rail Authority has asked the U.S. Forest Service to study the feasibility of running its proposed bullet train through the Angeles National Forest or the San Gabriel Mountains in a tunnel....."We have not made any decision on alignments at this point,” Alley{HSR authority} said. “This is just one of the many things that we do to gather information from an environmental perspective to look at the different and unique areas in possible alignments.”...

The forest service decision is at
I conclude that....(ii) The proposed use will be in the public interest. It will yield groundwater data that will help determine the feasibility of a high-speed rail under the ANF..

The next step to construct smaller "vertical" tunnels, of up to 2500ft and left in place forever, looks to be the NEPA process..."...Before being issued a use permit,  the Proponent will have to determine , through the NEPA process, and to the satisfaction of the Authorizing officer, that the proposed activities are harmonious with other Forest resources...."...before the big tunnels come in for the legal multi-use of the forest as directed by Congress according to the decision.

In other news, a federal rail administration ruled against a high speed rail through a national forest in Texas. In that case, HSR was proposed along an existing interstate highway that goes through NFS tunneling or carving up the forest. They havent reviewed the california rail segment south of Bakersfield yet....

Hey, AW, thanks for posting this and keeping us informed.

I'm not sure from this who will pay for the feasibility study, the HSRA or the Forest? If the forest is on the hook, it seems like yet one more item to drain funds from the recreational part of the "multiple-use" equation. It seems next to impossible to even manage graffiti removal and trash pickup from picnic areas as it is, and most people could tell you without drilling any holes that a tunnel under the San Gabriel Mountains is probably darn near infeasible.

I see they're taking comments if one is so inclined:

The Forest Service is collecting public comments on the rail authority’s application until Oct. 23, according to a press release issued Thursday.

“At this point in the application process, we are seeking comments only on the feasibility study, not the selection or construction of any route under the forest,” the release says.

The release adds that, “Approval of this application for the study does not constitute Forest Service approval or endorsement of any future high-speed rail alignment.”

Comments may be sent by mail to Angeles National Forest and San Gabriel Mountains National Monument, Attn. George Farra, 701 N. Santa Anita Ave., Arcadia, CA 91006.

Email comments can be sent to with the subject line “HSRA GI.”

walker wrote:
and most people could tell you without drilling any holes that a tunnel under the San Gabriel Mountains is probably darn near infeasible

Unless "most people" are geologists or civil engineers, I wouldn't put much weight into their thoughts on the matter

walker wrote:
It seems next to impossible to even manage graffiti removal and trash pickup from picnic areas as it is

The sad thing is, when you learn the actual recreation budget on the Angeles you will be amazed that they do what they do. The entire budget for the Recreation unit on San Gabriel River Ranger District, one of the most heavily used districts in the country, is less than the budget for office supplies in my department of 11 people.

Almost all of the money in the Forest Service goes to fire. Those guys have a blank check, and they act like it. Every cent they spend is a cent not spent on recreation.

Back in 1990, the SGRRD had 20+ full-time recreation employees. Today they have two.

dima wrote:
walker wrote:
and most people could tell you without drilling any holes that a tunnel under the San Gabriel Mountains is probably darn near infeasible

Unless "most people" are geologists or civil engineers, I wouldn't put much weight into their thoughts on the matter

They've already approved it.....being a facade for a few select groups who accomplished a land grab. I dont know what the comments are for....its been called an "unusual" process. Thats a kind word to call this proposal  that was received by the FS Sept 8.  It was then approved Sept 8. Thats all you need to know how feasible it is. They had worldwide experts already testifying that its feasible. This proposal is saying..'Look, unless we hit gold or diamonds which is worth more than what we can take from you via taxes...'. The standard for feasibility is really low. Lets not forget, the road to nowhere was deemed legit and feasible by the FS. And that had a plan of a bridge over Iron Fork 1000ft off the ground.


LA Times article on rail which infers the FS approval goes all the way.

...The bullet train will require about 20 miles of tunnels under the San Gabriel Mountains between Burbank and Palmdale, involving either a single tunnel of 13.8 miles or a series of shorter tunnels.

As many as 16 additional miles of tunnels would stretch under the Tehachapi Mountains from Palmdale to Bakersfield.

The state will probably opt for twin bores — one for each of two parallel tracks. That means as many as 72 miles of tunneling before 2022.

Can it meet that schedule?

"No way," said Leon Silver, a Caltech geologist and a leading expert on the San Gabriel Mountains. "The range is far more complex than anything those people know."

Herbert Einstein, an MIT civil engineer and another of the nation's top tunneling experts, said, "I don't think it is possible."

"Having looked at a number of these long tunnels, [the California] plan is aggressive," said Einstein, who has consulted on a 35-mile-long tunnel under the Swiss Alps. "From a civil engineering perspective it is very, very ambitious — to put it mildly."

Thomas O'Rourke, a Cornell University tunnel expert, also has doubts.

"My first gut reaction is that it is doable, but given the complex geology it is optimistically biased," O'Rourke said. "There are a lot of unknowns. It is going to depend on the complexity of the geology and the ground conditions."

Monsees, who retired in 2013 from Parsons Brinckerhoff as its senior vice president for tunneling, added, "They are behind and need to get off their rear end and move."

The rail authority declined to make any of its tunneling engineers available for interviews....

Silver, the Caltech geologist, said the San Gabriels' oldest rocks formed 1.7 billion years ago, 200 miles to the south. They became highly fractured as they were shoved north by movements of the Earth's crust.

Tunnelers will find that rock types change frequently, creating conditions that are among the most challenging for tunneling.

"If it were one single mass of granite, it would be easy to drill through and provide structural support," said Silver, who trained the Apollo astronauts in lunar geology and pioneered the dating of the San Gabriel Mountains. "But everything in the arc has been bent, shoved, stretched, compressed and metamorphosed."

The mountain range lies in a giant crescent between two major faults, the San Gabriel and the San Andreas, which separates the Mojave Desert on the North American tectonic plate from the Los Angeles Basin on the Pacific plate.

Between the two major faults are many secondary faults. Some are vertical strike-slip faults that move laterally, and some are thrust faults that move vertically. Some are horizontal, traveling through the ground at various depths.

"Every one is going to slow things down tremendously," said Monsees, the former Parsons Brinckerhoff tunnel expert.

A 2012 report by Parsons Brinckerhoff, obtained by The Times, warned the rail authority that the "seismotectonic complexity ... may be unprecedented" and that the rail route would be crossing faults classified as "hazardous."

The faults, changes in rock types and shattered rock cause many headaches, sometimes requiring changes in cutter heads. Doing so means stopping the machines while technicians crawl to the front to manually swap out as many as 40 to 60 cutter heads. A full swap of cutter heads can take an eight-hour shift, the engineers said.

Shattered rock causes additional problems in supporting the overhead formations, requiring workers to bore 10-foot-long holes into the ceiling and insert rock bolts that knit together blocks that weigh tons.

Morales, the rail agency chief executive, said he did not know what rates of advance will be possible. He said that will be determined by the contractors the state hires.

In good rock, such as limestone or chalk, TBMs can advance 100 to 200 feet a day. But in fractured mixed rock through fault zones, the advance rates can slow to 10 to 20 feet a day, Einstein of MIT said.

Einstein's estimate is endorsed by other engineers, including one who has worked closely on the bullet train project and told The Times that 10 feet a day is the likely rate of advance.

The schedule will depend in part on the number of TBMs and other smaller tunneling machines the state uses, with each machine and its crews adding to costs. The 36 miles of tunnels include a mix of short and long segments, dug by different methods.

The longest possible tunnel, described as one alternative in state documents, would stretch 13.8 miles under the Angeles National Forest. Assuming TBMs started at both ends and advanced at 20 feet a day for 261 days a year, the tunnel would take seven years to complete — finishing in 2026. At an advance rate of 10 feet a day, the time would double to 14 years.

The state is considering a different route under the national forest that would instead require a tunnel of just 7 miles. It would take 31/2 to seven years to dig, based on the same advance rates. But that route faces significant political opposition.

Only after the tunnels are dug can the next phase begin: installing track and other equipment in the 36 underground miles. By way of comparison, the Swiss are taking more than four years after tunneling to install track and equipment in the 35.4-mile-long Gotthard Base Tunnel through the Alps, a project spokesman said. Contractors will take an additional nine months to test the systems.

The route through the Tehachapi Mountains from Palmdale to Bakersfield, crossing several major faults, is at an even earlier level of planning.

The last formal analysis was issued more than three years ago. It said that as many as 16 miles of tunnels and as many as a dozen viaducts would be required. The possible routes were later found to be problematic because they are steep and would conflict with a massive wind farm. The agency is working on a new analysis....

I was wrong on the previous detail because its been clarified that the earlier approval was just an approval that the drilling could be considered.

Now the FS has given the final approval on the special use they can get started.

Kind of like in the 1950s when they wanted to have a tunnel with big fans to suck out the smog. Yea, I'm old.

Semi-official announcement confirming the rumors that HSR is cancelling plans to go to SoCal first.
HSR may or may not be back to test the waters later on. A huge win for opponents of HSR through the mountains!

"It is obviously a great victory for Silicon Valley, and it reflects on our solidarity in support of the project," said Rod Diridon Sr., whom that station is named after. Diridon, past chairman of the High-Speed Rail Authority, is director emeritus at the Mineta Transportation Institute at San Jose State.

He said "L.A. lost" because there was too much opposition in the San Fernando Valley and north Los Angeles County "by a very small group of horse and cattle owners in the area."

"Eventually it will go through, undoubtedly because it's really necessary, and L.A. County and city will not stand for them being left out." Forum Index -> General Discussion
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