At sunset in Martinez, CA, a couple of teenagers using the Santa Fe right of way to get home seem oblivious to the danger coming up fast behind them. The engineer of 7412 West, a 199 train, is leaning to the right in his seat in hopes of spotting where exactly the two young men are. Battling the 1.0 percent grade of Vine Hill, in a few moments the train will enter tunnel 1.