It is the GC policy to have no surface disturbance on GL. The exception to that is where they don't own the mineral and gas rights for the land the GL rest on (about 75% in the Marcellus gas play area.)
Pipelines, unknown how many there are, and I would think a gas line would be more beneficial to wildlife. I also don't know the official policy on how the GC looks upon them. I do know that in the past they have resisted gas lines over game lands. they have also insisted on alternative routing when they had to allow them.
I would contact the GC HQ in Harrisburg and ask your question.
The reason I asked is because Sprectra Eneryg has announced a new pipeline for gas that will run from the compressor station below Bedford to the Md line. From the map I saw, it looks like it could be on sgl 48 most of the way. With the Game commission lands now now becoming a major supplier of gas, it would seem logical to me that they would use this sgl for the pipeline particularly since since they think the lines make could food plots without and access points without much of a negative after the initial construction.