Complex sentence: It was also reasonably close to Boulder (about 80 km, 49.3 mi), which made it easy to staff and manage, but much farther away from the mountains, which made it a better choice for broadcasting an omnidirectional signal.
Split into simpler sentences: It was also reasonably close to Boulder (about 80 km, 49.3 mi), which made it easy to staff and manage; but much farther away from the mountains. The increased distance from the mountains made it a better choice for broadcasting an omnidirectional signal.