NTSB Safety Recommendation P-78-005

NTSB safety recommendation P-78-005.

INVESTIGATE THE FEASIBILITY OF DETECTING PIPELINE LEAKS BY THE USE OF ELECTRONIC IN/OUT FLOW MONITORS OR OTHER LEAK DETECTION DEVICES, AND INSTALL ONE CAPABLE OF DETECTING BOTH SMALL AND LARGE LEAKS.

Priority: CLASS III

Overall Status: Closed - Acceptable Action

Issued Date: 1978-02-08

Adopted Date: 1978-01-12

Overall Date Closed: 1987-03-10

Synopsis: ON JULY 20, 1977, A 12-INCH PROPANE PIPELINE, OWNED BY THE CONSOLIDATED GAS SUPPLY CORPORATION, RUPTURED NEAR THE TOWN OF RUFF CREEK, PENNSYLVANIA. THE LIQUID ESCAPED FROM THE PIPELINE, VAPORIZED, AND PROPANE VAPORS SETTLED LIKE A FOG OVER THE BOTTOM OF A VALLEY. TWO MEN IN A PICKUP TRUCK ENTERED THE PROPANE CLOUD; THE TRUCK STALLED AND THE PROPANE GAS IGNITED WHEN AN ATTEMPT WAS MADE TO RESTART THE TRUCK. THE 2 PERSONS IN THE TRUCK WERE KILLED.

Ntsbnumber: DCA77MP027

Report Number: PAR-78-01

Addressee Name: Consolidated Gas Transmission Corporation

Addressee Status: Closed - Acceptable Action

Addressee Date Closed: 1987-03-10

Addressee Organization Type: P-Private Industry

Communication Date: 1978-07-17

Communication Type: Official Correspondence

Communication Contents: CONSOLIDATED GAS SUPPLY CORP. LTR: AN ACOUSTIC PIPELINE MONITORING SYSTEM WAS INSTALLED ON LINE G-136 IN JANUARY 1978, AND BECAME OPERATIONAL ON MARCH 7, 1978. THE SYSTEM, MANUFACTURED BY BETHANY INTERNATIONAL, INC., MONITORS FROM BOTH ENDS OF THE SYSTEM ALONG WITH A DISTANCE CALCULATOR TO ALLOW FOR CALCULATING THE DISTANCE FROM HASTINGS TO THE LEAK, LINE BREAK OR OTHER MALFUNCTION. THE SYSTEM IS CONSIDERED EXPERIMENTAL ON LIQUIDS LINES AND WILL BE OBSERVED CLOSELY FOR A PERIOD OF TIME. ADDITIONAL TESTS AND OPERATING TIME ARE REQUIRED IN ORDER TO EVALUATE THE SYSTEM. 1/23/79 CONSOLIDATED GAS SUPPLY CORP. LTR: THE EVALUATION OF THE BETHANY INTERNATIONAL ACOUSTIC MONITORING SYSTEM IS STILL IN PROGRESS. SENSITIVITY SETTINGS ARE NOW BEING DETERMINED. THE SYSTEM IS STILL CONSIDERED EXPERIMENTAL. EVALUATION WILL CONTINUE WITH THE OBJECT OF GETTING THE SYSTEM FINE TUNED TO THE EXTENT THAT IT WILL MEET THE REQUIREMENTS OF A POSITIVE LEAK DETECTION DEVICE.

Addressee Organization Type: P-Private Industry

Communication Date: 1986-08-21

Communication Type: Official Correspondence

Communication Contents: THIS IS ACTUALLY A FOLLOWUP AND THE FOLLOWING IS A HISTORY OF PAST CORRESPONDENCE. CONSOLIDATED GAS LETTER OF JULY 17, 1978. NTSB LETTER OF SEPTEMBER 9, 1978. CONSOLIDATED FUR THER RESPONSE OF JANUARY 23, 1979. NTSB LETTER OF MARCH 14, 1979. CONSOLIDATED GAS LETTER OF MARCH 30, 1979. NTSB LET TER OF APRIL 30, 1979.

Addressee Organization Type: P-Private Industry

Communication Date: 1986-12-30

Communication Type: Official Correspondence

Communication Contents: SINCE THE INSTALLATION OF THE BETHANY PIPELINE ACOUSTIC MONITORING SYSTEM (AMS) ON G-136, ONLY ONE OF THE 26 LEAKS THAT WERE IDENTIFIED ON THE 12" PIPEING AND REPAIRED WAS SENSED BY THE AMS. OF THE REMAINING 25 LEAKS, MOST WERE DISCOVERED DURING PERIODIC LINE PATROL AND SOME WERE REPORT ED BY THIRD PARTIES. THE INE ALARM BY THE AMS DID NOT DE TECT THE LEAK BUT SENSED THE CLOSING OF AN AUTOMATIC VALVE WHEN THE LEAK WAS OF A MAGNITUDE TO INITIATE CLOSURE. OVER THE PAST NINE YEARS, NUMEROUS FALSE ALARMS HAVE OCCURED BE CAUSED THE SENSITIVITY OF THE EQUIPMENT IS SUCH THAT PRACTI CALLY ANY VIBRATION SOURCE LIKE PUMP PULSATION OR OTHER OR DINARY LINE NOISE CAN TRIGGER AN ALARM WHILE A LEAK PROBABLY WILL NOT. THESE HAVE HAD TO BE TRIGGER AN ALARM WHILE A LEAK PROBABLY WILL NOT. THESE HAVE HAD TO BE INVESTIGATED BY CREWS AT CONSIDERABLE EXPENSE WITHOUT FINDING LEAKS. THE EFFECTIVENESS OF THE AMS IS QUESTIONABLE. THE DISTANCE CAL CULATOR HAS PROVEN TO BE EFFECTIVE THROUGH SIMULATED TESTS. FOR ININSTANCE, A 1/2 VALVE OPENED AT ONE OF THE LINE JUNC TIONS WAS CALUCATED TO BE 19. 34 MILES. THE ACTUAL DISTANCE WAS 19.27 MILES OR WITHIN 369 FEET. ADDITIONALLY, THE EQUIPMENT HAS BEEN DAMAGED BY LIGHTING ON AT LEAST ONE OC CASION. THE PRESENT EQUIPMENT IS NO LONGER MANUFACTURED AND WE DO NOT HAVE AN INVENTORY OF SPARE PARTS NOR CAN WE OBTAIN ANY. NEVEDA-BENTLY HAD ONCE CONSIDERED ACQUIRING THIS PRO DUCT LINE BUT DETERMINED IT WAS NOT AVIABLE VENTURE. TO OUR KNOWLEDGE, NO ONE ELSE OFFERS SIMILAR EQUIPMENT. SINCE THE JULY, 1977, INCIDENT ALL OF THE 12" BARE PIPING HAS BEEN REPLACED WITH 6" COATED AND WRAPPED PIPE AND PROPER CATHODIC PROTECTION SYSTEM IS INSTALLED ON THE FACILITIES. THERE FORE, BASED ON THE ABOVE, CONSOLIDATED WILL BE REMOVING THE AMS FROM OPERATION IN THE NEAR FUTURE.

Addressee Organization Type: P-Private Industry

Communication Date: 1979-03-14

Communication Type: Official Correspondence

Addressee Organization Type: P-Private Industry

Communication Date: 1986-08-21

Communication Type: Official Correspondence

Addressee Organization Type: P-Private Industry

Communication Date: 1987-03-10

Communication Type: Official Correspondence