IIRC, all of this was studied a few years ago, and UP and Amtrak came to an agreement on double tracking the Cima Hill part of this run (Kelso to Cima, which is 2.2% grade), which would prevent Amtrak from having to follow freights struggling up the hill.

About that time, the enviros went into warp drive about what the construction work to add the second track would do to the habitat of the endangered desert tortise and began filing complaints and suits to stop it or delay it endlessly. Also about that same time, Amtrak ran out of money for such projects, and various studies showed the market just wasn't there in the first place.

Again, this is all IIRC, and could be wrong in some or all parts.

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