AMERICAN MIDSTREAM (ALATENN), LLC — Gas transmission and gathering — incident on 2017-02-27

Gas transmission and gathering incident in Not Within a Municipality, COLBERT COUNTY County, AL. Reported cause: OTHER OUTSIDE FORCE DAMAGE. Reported consequences: 0 fatalities, 0 injuries, 549 NATURAL GAS released, $56,000 reported property damage. Operator-reported incident data submitted to PHMSA, generally within 30 days. Records may be supplemented or corrected and do not represent final agency causal findings.

Report number: 20170032.

Operator ID: 189.

Reported incident date: 2/27/2017 15:51.

Location detail: STATION #832

Cause detail: OTHER OUTSIDE FORCE DAMAGE

Cause detail: OPERATIONS PERSONNEL AND CONTRACTORS FOUND A SMALL LEAK ON A DRIP LEG OFF THE MAINLINE. EXCAVATION OF THE LEAK IDENTIFIED APPARENT FAILURE AT A WELDMENT ON THE SMALL BORE DRIP PIPING. ADDITIONAL METALLURGICAL ANALYSIS BY STRESS ENGINEERING IN HOUSTON, TX FOUND THE FOLLOWING CONCLUSIONS: 1) THE PIPE ADJACENT TO THE SOCKOLET WELD FRACTURED. THE FRACTURE ORIGINATED AT THE OUTSIDE SURFACE FROM AN OVERLOAD DUE TO UNDETERMINED EXTERNAL FORCES. THE FRACTURE SURFACE PREDOMINANTLY EXHIBITED DUCTILE DIMPLES AND 45 DEGREE SHEAR LIPS. A FLAT REGION ON THE FRACTURE SURFACE EXHIBITED A BRITTLE-CLEAVAGE TYPE FRACTURE. SUMMARY OF OTHER CONCLUSIONS: 2) THERE WAS SOME INTERNAL CORROSION PITS AND EROSION NOTED IN THE SAMPLE. 3) METALLOGRAPHY THE PIPE AND SHOWED ELONGATED GRAINS AT THE FRACTURE ON BOTH OUTSIDE AND INSIDE SURFACES. THE PIPE AND SOCKOLET HAD A FERRITE-PEARLITE STRUCTURE, TYPICAL OF CARBON STEELS. 4) THE PIPE HAD AN AVG. HARDNESS OF 93 HRB, WITH MECHANICAL AND CHEMICAL PROPERTIES TO ASTM A106 GRADE B. TWO NRC REPORTS WERE FILED FOR THIS INCIDENT: 1) INITIAL NRC REPORT 1174017 MADE 3/25/2017 AT 14:22 CST WHEN COST OF REPAIRS DISCOVERED TO EXCEED $50,000. 2) SUPPLEMENTAL NRC REPORT 117064 MADE 3/25/3027 AT 12:15 CST TO UPDATE RELEASE QUANTITY OF GAS TO 2,125MCF. THE FINAL VOLUME CALCULATIONS SHOW A TOTAL OF 1831MCF WAS RELEASED, 549MCF UNINTENTIONALLY AS A RESULT OF THE LEAK AND 1242 MCF TO BLOW THE LINE DOWN FOR REPAIR & 40 MCF TO PURGE IT TO PUT IT BACK INTO SERVICE. SUPPLEMENTAL 30 DAY REPORT TO CORRECT GPS COORDINATES: LATITUDE: 34.727073, LONGITUDE: -87.85006. MAY 9 2018: REPORT CLOSED AS FINAL, NO UPDATE REQUIRED.

PHMSA trend classification: not significant, not serious.

PHMSA standardized cause: OTHER OUTSIDE FORCE DAMAGE — OTHER OUTSIDE FORCE DAMAGE.

PHMSA indexed costs: $67,119 reported total cost, $35,167.225 in 1984 dollars, $80,603.981 in current-year dollars.

PHMSA trend flags, standardized causes, and indexed costs are analytical fields added to operator-reported incident data. They do not represent final agency causal findings.