The company said this week in its July performance report that it loaded 952 coal trains last month in the Southern Powder River Basin. That is a 16% increase over June’s total of 820.

However, it did not quite beat the July 2011 result of 1036 total loadings.

Shipments from UP’s other main service area, the Colorado-Utah region, was up to 243 trains in July compared to 214 last year. The result is the highest monthly total so far this year, and is up notably from June’s result of 225 loadings.

Union Pacific, like several of its fellow coal rail contemporaries, has suffered a couple of derailments over the past few weeks.

One of those occurred July 27, when 27 cars left the tracks near Brookville, Kansas, halting loaded and empty coal train traffic moving east from Colorado and Utah.

That incident, which occurred one month to the day after one of its trains from Colorado derailed in Junction City, Kansas, was cleared quickly and the track was back in service one day later.

A second incident occurred just after the first of the month, when eight cars derailed August 4 in Richmond, Nevada. The line from Utah to Nevada and California was blocked until the crews completed cleanup and repair.

No official causes have been released for any of the events.

UP’s operation area encompasses 23 states in the western two-thirds of the US.

Burlington Northern Santa Fe and UP are the two largest shippers for the western coalfields.