ASCEND PERFORMANCE MATERIALS TEXAS INC

Incident Narrative

CONTINUATION: ASCEND ENGAGED A PIPELINE INTEGRITY MANAGEMENT SERVICES COMPANY WITH EXPERTISE IN DIRECT ASSESSMENTS, CATHODIC PROTECTION, CORROSION ENGINEERING, AND METALLURGICAL ANALYSIS TO HELP INVESTIGATE THE ROOT CAUSE OF THE SUBSURFACE PIPELINE LEAK. ASCEND ALSO UTILIZED A LEADING MATERIALS TESTING LABORATORY TO PERFORM METALLOGRAPHIC AND FRACTOGRAPHIC EXAMINATIONS AND CHEMICAL ANALYSES OF THE PIPELINE SEGMENT. THE SEGMENT WAS INSPECTED IN THE FIELD, EXCISED FOR OFF-SITE EXAMINATION AT THE MATERIALS TESTING LABORATORY, AND THOROUGHLY ANALYZED AT THE LAB. ADDITIONAL POST-INCIDENT FIELD WORK, INCLUDING A CLOSE-INTERVAL SURVEY, WAS ALSO CONDUCTED IN SUPPORT OF THE ROOT CAUSE ANALYSIS. BASED ON THE VARIOUS FIELD AND LABORATORY ANALYSES, THE ROOT CAUSE OF THE SUBSURFACE PIPELINE LEAK WAS DETERMINED TO BE ACCELERATED, LOCALIZED, STRAY DIRECT CURRENT-INDUCED CORROSION CAUSED BY CATHODIC PROTECTION (CP) SYSTEM INTERFERENCE (CP INTERFERENCE) ON THE PIPELINE. THE PIPELINE HAS A CP SYSTEM DESIGNED TO PROTECT THE PIPELINE FROM CORROSION; HOWEVER, A NEARBY, PRIVATE THIRD-PARTY (NON-DOT / RRC JURISDICTION) INSTALLATION WAS FOUND TO HAVE BEEN CONSTRUCTED IN THE AREA AND THAT INCLUDED A CP SYSTEM FOR ITS OWN PROTECTION. A MISSING / BROKEN CONNECTION WAS FOUND ON THE THIRD-PARTY CP SYSTEM. THE CONNECTION FAILURE RESULTED IN EXCESS CATHODIC POTENTIAL FOR THE CONNECTED PORTION OF THE THIRD-PARTY INSTALLATION, AND THE EXCESS CP INTERFERED WITH THE PIPELINE CP SYSTEM.