PEOPLES NATURAL GAS COMPANY LLC

Incident Narrative

ON 1/23/2013 AT 1:03 AM PNG GAS CONTROL RECEIVED AN OVER PRESSURE ALARM FORM SYSTEM 217, 60TH STREET DISTRICT REGULATOR STATION (LS 1723) IN ALTOONA, PA. AT 1:10 AM A GAS MEASUREMENT AND REGULATION TECHNICIAN WAS DISPATCHED AND ARRIVED ON SITE AT 1:50 AM. AFTER ACCESSING THE SITUATION, THE TECHNICIAN MANUALLY THROTTLED BACK INLET VALVES AND HAD THE SYSTEM BACK TO 150# MAOP BY 2:13 AM. POST INCIDENT EVALUATION OF REGULATOR REVEALED A BOOT FAILURE IN THE SYSTEM AND RELIEFS THAT DID NOT RESPOND TO TESTED SET POINT. FOLLOW UP ACTIONS TAKEN INCLUDE LEAK SURVEY OF ALL MAINS AND SERVICES WITHIN OVER PRESSURED SYSTEM BY 9:00 PM ON 1/23/2013. GAS MEASUREMENT AND REGULATOR TECHNICIANS CONTINUOUSLY MONITORED SYSTEM AND ON 1/24/2013, A WORKER-MONITOR SYSTEM WITH RELIEF WAS INSTALLED TO REPLACE EXISTING WORKER-RELIEF SET UP. ALL DOWNSTREAM REGULATING EQUIPMENT ON SYSTEM 217 WAS INSPECTED ON 1/25/2013. A SECOND FOLLOW UP LEAK SURVEY WAS CONDUCTED OF ALL MAINS AND SERVICES OF SYSTEM 217 ON 2/1/2013. A STANDBY REGULATOR RUN, LOCKED OUT OF SERVICE FROM TIME OF INCIDENT, WAS ALSO REVISED ON 8/19/2013 FROM WORKER/RELIEF TO WORKER/MONITOR PLUS RELIEF ON 8/21/2013, AND PLACED BACK INTO OPERATION. A FIELD TEST OF SYSTEM RELIEF VALVES WAS CONDUCTED ON 9/5/2013, CONFIRMING OVERPROTECTION CAPABILITIES UNDER LOAD.