Central Paving Products Pit ships pit-run gravel from its pit on the Palmer Branchline 35 miles north of Anchorage.  Although the loading process appears simple, it is actually an elegant ballet between the engineer, brakeman and tipple operator. From Frank Dewey's story, The Gravel Train:

The brakeman climbs up in the tipple with the tipple operator and the "dance" begins for the next 2+ hours. The engineer, in response to radio signals, creeps back at about .345 mph, the material comes off the belt at a rate of one ton per second. 100 tons, 100 seconds. If everything works right, when about 85 tons 20 feet of car is left, the brakeman tells the engineer "20 feet, next car" the engineer pulls back on the throttle raising the speed to about 1 mph, filling the rest of the car before the belt automatically shuts off at 100 tons. As the end of the next car begins to pass beneath the tipple the Brakeman says "10 feet", then "Loading'' as the chute gets completely over the hopper's slope sheet. This is very important timing as too early, it may dump between the cars possibly derail, at the least making a mess that has to be cleaned up later. Or too late the heavy material hitting the hopper doors directly popping them open (a real mess) or bending the doors over time. So it goes until all cars are filled.

Scoop to extract gravel from pit.	Lake where gravel is extracted.	Gravel travels under highway...	...across the yard...
...starting up the conveyor...	...almost to the top...	...and over the top into the pile.	Another view of yard conveyor.
Let's head to the loading zone.	A train pulls in to load.	Tipple operator radios engineer..	...and starts the conveyor...
...which brings gravel up...	...over the top...	...and into the hopper railcar.	Stop conveyor, start train.
Each car holds 100 tons max.	Precise speed for even loading.	Panoramic view.	Please tip your tour guide!

Click here for an aerial view of gravel loading or here for the entire gravel pit