A gas company’s failure to heed “ample warning signs”—including several fatal explosions—about its century-old mains led to a catastrophic 2011 blast that killed two families in Allentown, PA, state investigators have concluded.
In a scathing Formal Complaint filed Monday (June 11), the Pennsylvania Public Utility Commission’s Bureau of Investigation and Enforcement cited UGI Energy for 179 safety violations and fined the utility $386,000—the maximum possible—for the blast.
|It took the utility five hours to cut the gas flow to the fire, due to a lack of shutoff valves, investigators said.|
The complaint and report followed a 15-month investigation into the disaster that claimed five lives in two homes and destroyed several other homes on the freezing night of Feb. 9, 2011. The site was a half-mile from a school.
The complaint accuses UGI of ignoring well-known, decades-old problems in its cast-iron main network, which was installed in the late 1800s and early 1900s.
The origin of the 2011 blast was traced to a 12-inch circumferential crack in a pipe that had been installed in 1928.
The system had experienced more than one “reportable incident” per year since 1970, the PUC said.
Two of those “incidents” were fatal explosions. In August 1976, a gas explosion in the cast-iron system one-half mile from the 2011 site killed two firefighters, injured 14 people and destroyed four buildings.
In August 1990, an explosion in the system about one mile from the 2011 accident killed one person and injured nine, including two firefighters.
After the 1990 deaths, the National Transportation Safety Board found such severe graphitic corrosion in the main that it called a failure “inevitable,” even before water eroded the line’s soil foundation.
The NTSB “went on to warn UGI that numerous factors, individually or synergistically, have contributed to the integrity reduction and failure” of Allentown’s gas and water mains, the PUC noted.
The PUC cited a work authorization report from December 1979 that noted that the pipe had sustained four breaks in five years and recommended replacing it with steel pipe. That was the last repair note for the pipe until it exploded in 2011.
Replacement Not Necessary
Although UGI performed “numerous excavations” over the decades near the pipe that failed, the utility never deemed the pipe in need of replacement, the PUC said.
That may be because UGI’s pipeline replacement program does not factor in the size of the main, any changing environment variables such as soil stability and water encroachment, or the impact of excavation activity near the pipe, regulators said.
|Beatrice and William Hall perished in the explosion that blew apart their Allentown, PA, home in February 2011. Three other residents next door also died, and several homes were destroyed.|
Nor did a visibly sinking curb or fatigue cracking in the pavement near the failed pipe set off any replacement alarms, the PUC said.
In summary, the commission said:
“UGI failed to furnish and maintain adequate, efficient, safe and reasonable service and facilities, in that the company did not adequately and timely respond to ample warning signs regarding the integrity of its cast-iron mains in the Allentown area, including several catastrophic explosions resulting from corroded/graphitized mains, as well as a Class II Priority Action recommendation from the NTSB in 1992 following a fatal explosion, recommending replacing cast-iron mains on which graphitization was found in a planned and timely manner.”
Lack of Odorants, Testing Cited
The complaint cited other problems as well. It noted, for example, that it took UGI five hours after the explosion to turn down the flow of gas because of the system’s lack of shutoff valves.
The commission also found lapses in UGI’s odorant testing on the system. Residents reported no gas smell before the blast. Natural gas is odorless, and odorants are added as a safety feature. The PUC said UGI did not adequately test to ensure sufficient concentrations of odorant in the system and violated its own procedures in the process.
The PUC ruled that UGI must:
• Modify its safety testing procedures;
• Replace its cast-iron pipes within the next 10 years; and
• Replace any bare steel lines within 13 years.
The cost of those projects may not be added to customer rates, the commission said.
‘Not Just an Issue for Allentown’
Allentown Mayor Ed Pawlowski said the complaint should serve as a wake-up call to the utility.
“What is important is that UGI takes the alleged violations and the requests made in the formal complaint to heart and initiates steps to do everything possible to reduce the risk of another natural gas explosion,” Pawlowski told wfmz.com.
|Severe graphitic corrosion in a UGI cast-iron gas main caused a fatal explosion in 1979 just a mile from the area that ruptured in 2011. Investigators said the corrosion made the 1979 failure “inevitable” and urged that the line be replaced. It wasn’t.|
“As I have said all along, UGI needs to accelerate its plans to replace aging cast-iron piping. This is not just an issue for Allentown, but one that affects other municipalities across the region.”
In a statement Monday, UGI said it would formally respond to the commission within the required 20 days.
Meanwhile, UGI said its gas was “properly pre-odorized” with a substance called Mercaptan, which has a smell like rotten eggs. It said that the odorant had been checked and was detectable two days before the explosion.
“UGI also regularly checks its system to ensure safe operation and system integrity,” the utility said.
UGI said it had been “diligently working” on the investigation and remediation process since the disaster and had “cooperated fully” with the PUC investigation. The company said it had accelerated replacement of its cast-iron systems and would complete that work “over the next 20 years.”
“UGI knows that it is the company’s responsibility to safely deliver natural gas to our customers,” the company said. ”We take our responsibility seriously.”