TESTER VALVE BELOW A PRODUCTION PACKER

A downhole tester valve disposed below an isolation member in a test string may facilitate a shut-in drill stem test procedure. The positioning of the tester valve allows the tester valve to remain in a static location when the test string above the isolation member expands or contracts. The volume of a wellbore interval below the isolation member may remain constant and pressure readings over the duration of a shut-in DST test period may effectively be monitored. The tester valve is operatively associated with a communication unit that permits selective activation of the tester valve from across the isolation member, and in some example embodiments, an actuator for operating the tester valve is also is also operable to set the isolation member in the wellbore.