WBI ENERGY TRANSMISSION, INC.

Incident Narrative

A 2"" VENT LINE RELEASED NATURAL GAS AS A RESULT OF A PARTIAL FREEZE OFF OF THE SUPPLY GAS TO THE EMERGENCY SHUT DOWN SYSTEM. FREEZING OF THE SUPPLY GAS LINE RESULTED IN THE STATION NOT ISOLATING AND OPENING ONE BLOW DOWN VALVE RELEASING GAS THROUGH THE 2"" VENT LINE. SINCE THE FREEZE OFF PREVENTED THE STATION FROM ISOLATING, THE 2"" VENT LINE BLEW GAS UNTIL PERSONNEL WERE ABLE TO REACH THE SITE AND RESTORE OPERATION. THIS INCIDENT OCCURRED IN A RURAL LOCATION AT A COMPRESSOR STATION APPROXIMATELY 17 MILES NORTH OF GILLETTE, WY. THE SUPPLEMENTAL REPORT WAS SUBMITTED RESULTING FROM A RECOMMENDATION FROM PHMSA TO CHANGE THE CAUSE OF THE INCIDENT FROM 'G8 ' OTHER INCIDENT CAUSE' TO 'G2 ' NATURAL FORCE DAMAGE.' A SECOND SUPPLEMENTAL REPORT WAS SUBMITTED RESULTING FROM A RECOMMENDATION FROM PHMSA TO UNCHECK THE BOX ""INVESTIGATION IDENTIFIED NO CONTROL ROOM ISSUES"" IN PART E QUESTION 8. THE BOX WAS UNCHECKED SINCE WBI IDENTIFIED AND ADDED USEFUL SCADA POINTS TO HELP CONTROL ROOM OPERATORS IDENTIFY ABNORMAL CONDITIONS. APPENDED PART E5F TO TRANSMISSION SYSTEM PER DOT EMAIL REQUEST FROM BLAINE KEENER ON 3/4/13.