E145 FLT CREW DEPART THEIR ACFT WITH THE RIGHT ENGINE STILL RUNNING.

Narrative

WE HAD JUST PULLED INTO THE GATE. WITH THE CURRENT FUEL SAVINGS INITIATIVES IN MIND WE CHOOSE NOT TO START THE APU. WE EXPECTED TO RECEIVE GND PWR VERY SHORTLY AFTER ARR. UNTIL SUCH TIME WE DECIDED TO LEAVE ENG #2 RUNNING IN ORDER TO KEEP THE AIRPLANE PWRED WHILE THE PAX DEPLANED. WE COMPLETED THE SHUTDOWN CHKLIST TO THE POINT OF THE #2 ENG SHUTDOWN HAVING PREVIOUSLY DECIDED TO LEAVE IT RUNNING. AFTER DEPLANING MY FO LEFT THE FLT DECK TO CONDUCT THE POSTFLT INSPECTION. I KNEW THAT THE AIRPLANE HAD A RELATIVELY SHORT TURN TIME AND THERE WOULD BE NECESSARY CREW SWAP. IN ORDER TO EXPEDITE MATTERS I DECIDED I SHOULD START THE APU AND SHUT DOWN THE ENG. HOWEVER DUE TO DISTR AT THE TIME I NEVER DID THIS. I MADE AN ERROR IN THINKING THIS HAD BEEN DONE AND LEFT THE FLT DECK WITH THE ACFT IN GND SAFE MODE. THE NEXT CREW ARRIVED WITHIN MINS; DISCOVERED THE ENG; AND SHUT IT DOWN WITHOUT FURTHER EVENT. MY CREW AND I PASSED THE NEW CREW IN THE TERMINAL ON THEIR WAY TO THE AIRPLANE. ONCE THEY ARRIVED AT THE AIRPLANE THE NEW CAPT DISCOVERED THE ENG RUNNING AND SHUT IT DOWN. HE LATER CALLED ME AND TOLD ME. SUPPLEMENTAL INFO FROM ACN 795308: ALSO; FROM NOW ON; THE SHUTDOWN CHKLIST SHOULD NOT BE COMPLETED TILL BOTH ENGS ARE ACTUALLY FULLY SHUTDOWN.