There is usually 1 GRS locomotive, a high-nose GP35 (#380 or #381) on "permanent" lease to the CPRS. Its there to work off horsepower hours incurred when Guilford uses the CP Rail power on trains EDMO/MOED (or currently called MOPO/POMO) that run to East Deerfield.
Since 3 SD40-2s exceed the Horsepower total of 1 GP35 you can be sure someone runs at a deficit.
The occasional additional GRS unit will show up on NS empty coal trains to also make-up horsepower hours for the NS power that goes east on the Bow, NH coal trains. But its not always the case. There are also instances where the NS or CPRS power has had problems while departing Guilford so a GRS unit is tacked on to get the train over the road.
With the exception of the "leased" GP35s and the ex-GRS units now owned by the CPRS there generally is no "run-through" GRS power.
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