While I was prowling around, looking at the CP Rail line demolition in Pleasant Prairie, WI [id=336874057], this Amtrak train flew by. In looking more closely at the photograph, I noticed it was Locomotive 821, a 1993-vintage loco which was retired, refurbished, and placed back into service in 2010.

You can see the tracks in the grass on the right (western) side of the tracks which were left by the line demolition crew. The line itself is on the east side, but is not truck-accessible.

You can read more about it here: http://www.4rr.com/800/821_001.htm .

Excerpt: This is the first of fifteen 1993-vintage locomotives to be brought back from retirement in 2010 at Amtrak. Engine #821 was put out of service in 2005 due to being run-out and deemed beyond recovery. She has now re-entered service in February, 2010, after being rebuilt under the George Bush economic stimulus package of 2008.

The P40 was a new cab unit unitbody design developed at Amtrak's request on short notice. It became known at the P40 Genesis AMD-103 series. They were geared to run up to 103 mph, but Amtrak never regularly used them any faster than 79 mph. Amtrak purchased 44 of these, road number 800 through 843. The locomotives were delivered to Amtrak in 1993 and stayed in the original paint until the "northeastern" marketing scheme came along about five years later. All but 819 were given that livery. Along the way the two strobe lights and the clearance light over the top of the cab windows were removed. The newer 2001 style of bluenose paint has been applied to #821, and a whole bunch of new stickers applied. Another distinguishing factor for the rebuilt P40's, besides their road numbers, is the reinforced windshield frame, which do not yet appear on any of Amtrak's newer P42's. Windshields have a tendency to leak, and it may be the stiffer frames were required for that reason. Otherwise, we don't know why this change was made.

The P40 designation at GE and Amtrak was due to the original horsepower rating of the 7FDL power plant employed in them. The total 4000 horse output is not all available to run traction motors though, since all passenger locomotives now have a headend power generator which converts some of the engine output into electricity to power, heat, and cool, the rest of the train. The P40 and P42, in addition to being of unitbody construction, have the 16 cylinder version of the 7FDL power plant. Over the years, Amtrak updated the P40s to P42 standards, and also made several cosmetic changes. Amtrak accepted this GE design over a competing EMD locomotive partly because of the fuel efficiency. A computer controlled system and a redesigned fuel delivery system helped to make it more efficient. It also offered a vertical clearance advantage, which Amtrak needed at the time, because of limited clearances in tunnels along the eastern seaboard.