TEXAS EASTERN TRANSMISSION, LP (SPECTRA ENERGY PARTNERS, LP)

Incident Narrative

ORIGINAL REPORT: 48 HR NRC REPORT 1243693 AT APPROXIMATELY 1:04 PM EDT ON APRIL 23, 2019, AN EMERGENCY SHUTDOWN (ESD) SYSTEM WAS ACTIVATED AT ACCIDENT COMPRESSOR STATION ON THE TEXAS EASTERN TRANSMISSION (TETLP) SYSTEM IN GARRETT COUNTY, MARYLAND. TETLP COMPLETED THE REPORT TO THE NATIONAL RESPONSE CENTER AT APPROXIMATELY 4:23 EDT ONCE IT WAS DETERMINED THE GAS LOSS VOLUME EXCEEDED 3 MMSCF. THE ESD OCCURRED WHILE RETURNING A SALT BATH HEATER (SBH) BACK TO NORMAL OPERATIONS. THIS PROCESS INVOLVES USING GAS FIRED AUXILIARY BURNERS TO HEAT THE SALT TO A LIQUID STATE AND USING THE MAIN BURNERS TO KEEP THE SALT AT A LIQUID STATE AFTER THE GAS FIRED AUXILIARY BURNER IS DEACTIVATED. THIS PROCESS WAS BEING PERFORMED IN ACCORDANCE WITH THE MANUFACTURER'S RECOMMENDED PROCEDURE. THE ESD WAS TRIGGERED BY THE FIRE DETECTOR NEAR THE GAS FIRED AUXILIARY HEATER THAT DETECTED THE FLAME SIGNATURE. TETLP'S INVESTIGATION DETERMINED THAT BOTH THE AUXILIARY HEATER AND THE FIRE DETECTOR WERE FUNCTIONING AS DESIGNED AT THE TIME OF THE ESD. AS PART OF THE MITIGATIVE PLAN, THE TEMPERATURE OF THE GAS POWERED AUXILIARY BURNER WAS LOWERED DURING STARTUP. SUPPLEMENTAL REPORT 10/14/19: CAUSE HAS BEEN UPDATED TO INCORRECT OPERATION.