DCP MIDSTREAM

Incident Narrative

ON 8/9 AT APPROXIMATELY 13:30 AN NGL TECHNICIAN COMPLETED AN INTERNAL LEAK REPORT ON RED BLUFF LATERAL AT THE PECOS RIVER, BASED ON A SUSPECTED LEAK FOUND BY AERIAL PATROL USING A FLIR CAMERA. THE NGL TECHNICIAN IMMEDIATELY CALLED THE HOUSTON CONTROL CENTER TO SHUT DOWN THE RED BLUFF LATERAL AND THE OPERATIONS TEAM WAS ALSO NOTIFIED. NOTIFICATIONS WERE MADE TO THE NRC AND TXRRC. THE OPERATION TEAM THEN TRIED TO DETERMINE THE EXACT LOCATION OF THE LEAK. AFTER THOROUGHLY INVESTIGATING, THE LEAK WAS IDENTIFIED. BOOMS WERE LATER DEPLOYED AND WATER SAMPLES WERE ALSO TAKEN AS THE TEAM BEGAN EFFORTS TO REPLACE THE LEAKING PIPELINE AND MITIGATE THE AFFECTED AREA. THE BORE SECTION OF THE PECOS RIVER WAS REMOVED, REPLACED WITH A NEW BORE SECTION AND A TOTAL OF APPROXIMATELY 3232 FEET WAS HYDROSATICALLY TESTED INCLUDING THE NEW BORE. A SAMPLE OF THE REMOVED PIPE WAS SENT TO A 3RD PARTY ENGINEERING FIRM TO DETERMINE ROOT CAUSE. WHILE WAITING FOR THE REPORT DCP HAS INITIATED ADDITIONAL CORROSION MITIGATION EFFORTS. THE DRAFT REPORT RECEIVED FROM THE THIRD PARTY ENGINEERING FIRM INDICATED THE ROOT CAUSE OF FAILURE WAS DUE TO STRAY CURRENT CORROSION (AC AND DC INDUCED CORROSION). LOCATIONS WERE IDENTIFIED ALONG THE PIPELINE SEGMENT THAT POTENTIALLY HAD SIMILAR CONDITIONS TO THE PECOS RIVER CROSSING, FOCUSING ON FOREIGN LINE CROSSINGS, ROAD AND RIVER/STREAM CROSSINGS AND AC POWER CORRIDORS AS AREAS OF POTENTIAL CONCERN. DCP MIDSTREAM COMPLETED A TOTAL OF 31 EXCAVATIONS, NONE OF WHICH REVEALED ANY PRESSURE REDUCING ANOMALIES. FIELD INVESTIGATION OF THE ANOMALIES INDICATED THAT ONLY RECOATING WAS REQUIRED, HOWEVER, DCP MIDSTREAM DID DECIDE TO UTILIZE A COMPOSITE WRAP ON ONE (1) OF THE ANOMALIES. DCP RETURNED TO PIPELINE TO SERVICE ON 8/26/2016 AT A 20% PRESSURE REDUCTION WHILE ADDITIONAL MITIGATIVE MEASURES WERE TAKEN. DCP MIDSTREAM IMPLEMENTED THE FOLLOWING MEASURES WHICH INCLUDE THE INSTALLATION OF A NEW GROUND BED NEAR THE PECOS RIVER, BONDS WITH SELECT ADJACENT PIPELINES AS WELL AS THE INSTALLATION OF ZINC RIBBONS AND DECOUPLERS IN AREAS DEEMED AT HIGHER RISK FROM AC STRAY CURRENT. ADDITIONAL MEASURES TO BE IMPLEMENTED INCLUDE CONDUCTING A FULL PIPELINE CLOSE INTERVAL AND DCVG SURVEY AND THE INSTALLATION OF ONE NEW REMOTE MONITORING TEST STATION FOR ONCE PER WEEK READINGS (AC/DC) NEAR THE PECOS RIVER. DCP RAN A HIGH-RESOLUTION MFL ILI TOOL TO VERIFY AND VALIDATE THE INTEGRITY OF THE PIPELINE. THE PRELIMINARY RESULTS DETERMINED THERE WERE NO ANOMALIES SATISFYING THE ""IMMEDIATE CONDITION"" CRITERIA OUTLINED IN 49 CFR 195.452(H). THE SIX (6) DEEPEST METAL LOSS ANOMALIES WERE PROVIDED BY THE ILI VENDOR. DCP SELECTED THE SIX (6) WORST ANOMALIES TO BE EXCAVATED TO VALIDATE THE TOOL RUN BUT THE SAFE PRESSURE CALCULATIONS ON THE IDENTIFIED ANOMALIES WERE WELL ABOVE MOP. ONE OF THE EXCAVATED ANOMALIES WAS FOUND TO HAVE A PINHOLE LEAK AFTER EXCAVATION. STOPPLES WERE INSTALLED AND THE ANOMALY WAS CUT OUT. TWO OTHER ANOMALIES WERE REPAIRED WITH TYPE B SLEEVES, ONE ANOMALY WAS REPAIRED WITH A COMPOSITE WRAP, AND THE OTHER ANOMALIES WERE RECOATED. THE PIPELINE WAS RETURNED TO FULL SERVICE ON 10/12/2016