Answer: Section 2.7.1.6 of AC 150/5300-18b states, “If obstacles that are required in the primary area or first 10,000 feet of an approach area are located within 100 feet of each other, the lower obstacle may be omitted.”

This specification does not apply to obstacles within the Vertically Guided Protection Surface (VGPS), which extends 6,000 feet from the Runway End. Report all obstacles within the VGPS.