PST’s Data Manager James Eager walks us through one state’s pipeline safety track record each month. Click on the “State of Safety” tag at the bottom of the post to see all of James’s entries to date.
This analysis considers all incidents which occurred in Pennsylvania over the 2010-2022 time period, regardless if they fall under state or federal jurisdiction.
From 2010 to 2022, Pennsylvanian pipelines caused:
- 177 total reported incidents, including:
- 71 Hazardous Liquid incidents
- 49 Gas Transmission incidents
- 50 Gas Distribution incidents
- 4 Gas Gathering incidents
- 3 Underground Natural Gas Storage incidents
- 102 significant incidents
- 19 incidents ending in injury and/or fatality causing:
- 30 hospitalizations
- 11 fatalities
- 39 incidents resulting in fire and/or explosion
- 1,488 evacuations
- Incidents have released:
- 544,152 gallons of hazardous liquids
- 1,561,077 thousand cubic feet (mscf) of gas
Pennsylvania’s incident rate trends below the national incident rate and closely to the average of its neighbors (Plot 1). This trend holds among significant incidents alone (Plot 2).
The highest-cost incident was a gas transmission spill, as presented in Plot 3. Rounding out the five highest-cost incidents are another transmission spill, a hazardous liquid spill, an underground natural gas storage incident and a gas gathering incident. Both transmission incidents were caused by internal corrosion failure, the liquids incident was caused by incorrect installation of equipment, and the gathering incident was caused by natural force damage. The most expensive incident occurred on December 12, 2016 on a compressor station well part of Transcontinental Gas Pipeline Co.’s transmission system. A subsidiary of Williams Pipeline, Transcontinental realized damages totaling over $74 Million, adjusted for inflation.
Of the 146 unique pipeline operator IDs in Pennsylvania, 32 have been responsible for at least one incident since 2010. Seven of these 32 operate integrity management programs under a different primary operator. For example, Transcontinental Gas Pipeline Company operates integrity management under Williams Pipeline, suggesting that Williams is their primary operator.
The table below presents the three operators with the most incidents for each system in the state of Pennsylvania over the 2010 – 2022 period. The trend column displays their annual incident rate from 2010 to 2022, with a green point at their maximum and an orange point at their minimum. The row labeled “Other” is an average of the other parent operators for each given system in Pennsylvania – including those without any incidents during this period. Significant incidents are presented as a percent of total incidents, and incident rates are given as incidents per 1,000 miles. Finally, releases are reported in thousand standard cubic feet (mscf) for gas incidents and gallons (Gal.) for hazardous liquids.
|Parent Operator||2022 Mileage||Total||Percent Significant||per 1K Miles||Trend||Total||per Incident||Total||per Incident|
|ENERGY TRANSFER (HL)||1,261.43||32.0||56%||25.37||13,572||424||120,508||3,766|
|15 Others (HL, avg.)||29.00||0.5||14%||14.69||151||58||10,396||4,163|
|COLUMBIA GAS OF PENNSYLVANIA||13,368.99||9.0||78%||0.67||1,642||182||21,554||2,395|
|UGI UTILITIES, INC||15,847.39||9.0||67%||0.57||6,213||690||23,558||2,618|
|37 Others (GD, avg.)||1,149.59||0.5||10%||0.06||124||31||1,268||588|
|KINDER MORGAN (GT)||993.37||6.0||50%||6.47||1,151||192||123,730||20,622|
|98 Others (GT, avg.)||75.92||0.4||12%||18.37||126||102||4,313||2,200|
To offer a holistic view of the relative responsibility of operators in Pennsylvania, this table can be referenced in conjunction with Plot 4, which looks at each operator’s incident causes. This matrix presents a concerning suggestion: some large operators see a majority or plurality of their incidents caused by equipment failure. This cause is more easily addressed by operators and suggests significant room for improvement for a couple of major pipeline operators in PA. By comparison, nationwide, only about 36% of incidents are caused by equipment failure.
Plot 5 sheds some more light on which operators are responsible for some of the state’s worst incidents during this period. Using a grouped z-score of incident releases, we can identify which release sizes were well above average per system in the state during this period – as a z-score of 0 denotes the mean release size per system. The largest relative incident in the state was on a Tallgrass hazardous liquids line, spilling 420,378 gallons of crude oil – the sixth largest oil spill in the U.S. since 2010. This 2017 spill was caused by the equipment failure of a tank terminal installed in 2014. Other labeled incidents include those more than three times the average release size for their systems and those deemed serious per the Pipeline and Hazardous Materials Safety Administration’s (PHMSA) definition. According to PHMSA, serious incidents are those which require hospitalization of an injury or result in a fatality. The labeled serious incidents resulted in multiple fatalities.