Union Pacific will spend more than $1 billion to upgrade 600 of its old diesel locomotives over the next three years and make them more efficient, but.
Union Pacific will spend more than $1 billion to upgrade 600 of its old diesel locomotives over the next three years and make them more efficient, but regulators still want it to do more to cut pollution from its engines. The move will accelerate the pace of upgrades UP already planned to make and help…