How to Earth a Gas Wellhead Monitoring System

Hi every body,

well we have justed finished our SCADA installation which comprises of Honeywell PTs, Kobold TT, AB RTU, and sollatec Solar panel. It's basically a gas well head monitering systemand we have got an issue regarding the Pipe line mounted instruments i.e. PTand TT grounding.will you please help me out, as how that can be accomplished? thanks