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.
In a full audit report published June 12, the Colorado Office of the State Auditor discovered a plethora of major issues with Colorado’s Gas Pipeline Safety Program. Upon extensive review, the auditor found the Program failed to meet state and federal standards; including lack of proper training for its inspectors, refusal to enforce safety requirements, and failure to assess financial penalties for egregious violations of safety standards.
Because of this, we thought it pertinent to take a closer look at the state of Colorado’s pipeline incident history.
This analysis considers all incidents which occurred in Colorado over the 2010-2022 time period, regardless of jurisdiction. As such, it is not a reflection on Colorado’s Gas Pipeline Safety Program alone.
From 2010 to 2022, Coloradan pipelines caused:
- 115 total reported incidents, including:
- 56 Hazardous Liquid incidents
- 29 Gas Transmission incidents
- 28 Gas Distribution incidents
- 1 Gas Gathering incident
- 1 Underground Natural Gas Storage incident
- 55 significant incidents
- 10 incidents ending in injury and/or fatality causing:
- 13 hospitalizations
- 2 fatalities
- 25 incidents resulting in fire and/or explosion
- 3,302 evacuations
- Incidents have released:
- 1,019,588 gallons of hazardous liquids
- 853,625 thousand cubic feet (mscf) of gas
Colorado’s incident rate trends below the national incident rate and the average of its neighbors (Plot 1). Colorado is flanked by a couple of the highest incident rate states in the country; Texas, Oklahoma, New Mexico, and Kansas each have an incident rate in the top 10 over the time period analyzed. This trend holds among significant incidents alone (Plot 2), similarly highlighting Colorado’s neighbors above-average incident rates.
The highest-cost incident was a gas transmission spill, as presented in Plot 3. Rounding out the five highest-cost incidents are an underground natural gas storage incident and three hazardous liquid spills. Both gas incidents were caused by equipment failure while two of the three liquids incidents were caused by corrosion. The most expensive incident occurred on December 12, 2010 on an aboveground storage well that was part of Colorado Interstate Gas Co.’s transmission system. A subsidiary of El Paso Corporation – acquired by Kinder Morgan in 2012 – Colorado Interstate Gas Co realized damages totaling over $3.2 Million, adjusted for inflation.
Of the 104 unique pipeline operator IDs in Colorado, 29 have been responsible for at least one incident since 2010. Ten of these 29 operate integrity management programs under a different primary operator. For example, TransColorado Gas Transmission Company operates integrity management under Kinder Morgan, suggesting that Kinder Morgan is its primary operator.
The table below presents the three operators with the most incidents for each system in the state of Colorado 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 Colorado – 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.
|Primary Operator||Total||Percent Significant||per 1K Miles||Trend||Total||per Incident||Total||per Incident|
|38 Others (HL, avg.)||0.5||9%||9.82||55||46||5,583||2,884|
|XCEL ENERGY (GD)||17.0||82%||0.45||6,436||379||30,149||1,773|
|BLACK HILLS (GD)||5.0||80%||0.54||1,130||226||13,510||2,702|
|17 Others (GD, avg.)||0.4||9%||2.34||55||28||477||239|
|KINDER MORGAN (GT)||6.5||48%||8.52||2,216||236||262,302||29,671|
|XCEL ENERGY (GT)||6.0||50%||11.17||1,633||272||263,836||43,973|
|40 Others (GT, avg.)||0.3||4%||12.13||36||19||2,252||1,248|
To offer a holistic view of the relative responsibility of operators in Colorado, this table can be referenced in conjunction with Plot 4, which looks at each operator’s incident causes. This matrix presents a concerning suggestion: many large operators see a majority or plurality of their incidents caused by equipment failure and incorrect operation. These are a couple of causes that are more easily addressed by operators, so to see them cause such a high proportion of incidents is reason for concern. By comparison, nationwide, only about 36% of incidents are caused by equipment failure and just under 12% by incorrect operation.
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 twice 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.