MARKWEST OKLAHOMA GAS COMPANY, L.L.C.

Incident Narrative

8:21 AM DANNY MCPHETRIDGE RECEIVED A CALL FROM THE CALL CENTER A LANDOWNER REPORTED A LEAK 8:30 AM JIMMY RECEIVES THE CALL FROM DANNY AND CALLS DONNIE 8:33 AM DONNIE CONTACTED MITCHEL TO GET A LOCATE DONE AT THE LEAK SITE 9:00 AM LOCATE COMPLETED BUT NOT CONFIRMED IT WAS OUR LEAK OR LEAKING ON THE 6"" 9:08 AM DANNY LARKEY WAS CALLED OF OIL LEAKING ON CRUDE LINE 1-0-6 6"" LINE. MITCHEL BIEREN CHECKED IT OUT AND CALLED THE LOCATOR TO VERIFY IT WAS MPLX LINE. 9:10 AM LINE WAS SHUT DOWN AND ISOLATED 9:15 AM CONFIRMED IT WAS A MARKWEST PIPELINE 9:24 AM DANNY CALLED KD PIPELINE CONSTRUCTION - INITIAL CALL RECEIVED FROM REGION MANAGER REGARDING OIL SPILL IN THE STACK AREA. 9:30 AM CALLED 811 FOR AN EMERGENCY LINE LOCATE TO FIND THE LEAK TO CONTROL THE SOURCE AND BEGIN REPAIRS. 10:17 AM LINE LOCATE WAS MADE AND TRACKHOES WERE IN ROUTE TO THE NW 1/4 SECTION OF 36 17N 9W. THE LEAK IS LOCATED IN A HCA. RELATED WAS CALLED FOR ENVIRONMENTAL CLEANUP. 10:19 AM TALKED THROUGH EVENT/NECESSARY NOTIFICATIONS WITH T. MINUTILLO 10:47 AM MAPLINE CALL TO DISCUSS EVENT. 11:00 AM LUGREG WAS ON SITE TO START SUCKING UP THE SPILL IN THE BOTTOM DRAW. 11:30 AM JEREMY C. AND K. YOUNGS BOTH IN ROUTE TO SPILL SITE. KD'S OPERATOR SHOWED UP, MADE HOT WORK PERMIT AND HAD KD SIGN JSA. 12:00 PM RELATED ENVIRONMENTAL ON SITE TO ASSESS SPILL. SOIL SAMPLES COLLECTED. WILL BE TRANSPORTED TO LAB BY RELATED ENV. RELATED WILL COORDINATE SOIL REMEDIATION EFFORTS. 12:39 PM DUG SUMP HOLE FOR LUGREG. 1:15 PM JEREMY CANTRELL-(ENV SUPERVISOR ON SITE). 2:00 PM HENRY'S CONTRACTING SHOWED UP WITH A DUMP TRUCK AND KD BROUGHT A SECOND TRACKHOE ON SITE. 2:15 PM BEGAN DIGGING BELL HOLE AND HAULING DIRT UP THE HILL AT 2:15 PM AND PUTTING DIRT ON PLASTIC. 3:14 PM K.YOUNGS CONTACTED BASIN ENV RESPONSE LINE, AND THE TEAM WAS ALREADY DEPLOYED, SO A SUB-CONTRACTOR (ACME ENV) OUT OF OKC INITIATED THEIR RESPONSE TEAM TO THE SITE. 4:40 PM SPOTTED THE LINE AND BEGAN STRIPPING. MUD MATS WERE BROUGHT IN AS A SAFETY PRECAUTION. 5:10 PM ODEQ CONTACTED BY K. YOUNGS AS A COURTESY TO ENSURE THIS FELL TO OCC'S JURISDICTION. K. YOUNGS WAS INFORMED THAT SO LONG AS THE OIL DIDN'T GO INTO DRINKABLE WATER, JURISDICTION REMAINS WITH OCC. 5:27 PM THE ANOMALY WAS LOCATED ON THE BOTTOM 6 O'CLOCK POSITION OF THE PIPE. 5:30 PM PLANS WERE MADE TO BEGIN SKIMMING OIL FROM POND FIRST THING ON 12/27. 5:40 PM CLAMP WAS TIGHTENED ONTO THE LINE AND THE LEAK WAS STOPPED. PLANS BEING MADE TO DE-INVENTORY PIPELINE AS WELL AS A METHOD OF REPAIR. A METALLURGICAL FAILURE ANALYSIS WAS PERFORMED BY DNV-GL ON A CUT-OUT SECTION OF THE 6"" PIPE AT THE FAILURE LOCATION. CONCLUSIONS OF THE REPORT ARE AS FOLLOWS: - THE PIPE LEAKED DUE TO AN INTERNAL CORROSION PIT, LOCATED AT THE 6 O'CLOCK ORIENTATION. - EVIDENCE POINTS TO MICROBIOLOGICALLY INFLUENCED CORROSION (MIC) AS THE LIKELY MECHANISM. - THE TENSILE STRENGTH AND CHEMISTRY MEET THE REQUIREMENT FOR API 5LX GRADE X52. - MICROSTRUCTURE OF THE PIPE SECTION IS CONSISTENT WITH THE GRADE OF STEEL. IMMEDIATE ACTIONS TAKEN ALTHOUGH THE LINE SECTION WAS PREVIOUSLY TREATED WITH A BIOCIDE AND MONITORING RESULTS DID NOT INDICATE HIGH LEVELS OF CORROSIVE BACTERIA, THE BIOCIDE TREATMENT PROGRAM HAS BEEN ENHANCED. BIOCIDE SLUGS IN THE LINE SEGMENT WERE INCREASED FROM 1X PER MONTH TO 2X PER MONTH IN CONJUNCTION WITH MAINTENANCE PIGGING. THE BIOCIDE SLUG NOW ALSO INCLUDES A CORROSION INHIBITOR COMPONENT TO PROTECT EXISTING PITS FROM FURTHER CORROSION MECHANISMS. PIGS WERE CHANGED TO A MORE AGGRESSIVE CLEANING DESIGN. LONGER TERM PROJECTS PLANNED LABORATORY TESTING OF BIOCIDES TO ENSURE OPTIMUM TYPE, DOSAGE, AND FREQUENCY FOR THIS APPLICATION. WE ARE REEVALUATING THE CURRENT CORROSION MONITORING PROGRAM, TO DETERMINE OPTIMUM CORROSION COUPON LOCATIONS AND EVALUATE USE OF PROBES, SESSILE BACTERIA DEVICES, AND UT SENSORS TO IMPROVE MONITORING CAPABILITY.