This will be a posting that will take awhile to finish. This is the first draft.
This twin pipeline rupture in Kentucky had a major impact on pipeline corrosion control in the USA.
The major impact was a realization of the limitations of cathodic protection due to shielding issues that existed as a cause in both ruptures. Beaumont rupture was due to a highway casing shielding cathodic protection current. This caused government regulators to demand that the pipeline operator run smart pigs in Kentucky to verify the intregity of the pipeline as this was the only method of verifying that other cased pipeline crossings didn't have serious corrosion damage. This caused the start of the transfer of pipeline integrity budgets from CIS (Close Interval Survey) to upgrading of pipelines to run smart pigs and the running of smart pigs. Cathodic protection staff tended to considered the smart pigs to be experimental devices of questionable value, but government regulatory staff viewed smart pigs as the future of pipeline integrity and some pipeline operators who has experimented with smart pigs agreed. Smart pigs at that time were low resolution and not as accurate at sizing corrosion pitting as present day tools. The lack of accuracy in sizing corrosion pitting and claims that CIS was sufficient was the argument used by pipeline operators who were not impressed with smart pigs prior to the Beaumont incident.
Lancaster pipeline rupture occurred about a year later and resulted in more government regulations related to smart pigging since this rupture should not have happened. Once again the corrosion damage that caused the pipeline rupture was due to shielding of cathodic protection, but this time it was a rock in contact with the bottom of the pipe. A smart pig had found the significant corrosion damage and the pipe was incompletely inspected because of the rock. Two pipe inspectors couldn't agree on the seriousness of the corrosion damage due to the rock the pipe was in contact and no attempt was made to expose sufficient pipe to raise the pipe off the rock so that a complete inspection could be made. the pipe was recoated as best as possible with a rock in contact with the pipe and buried. Later the pipeline ruptured and the pipeline operator had to explain how corrosion damage not detected by CIS but found by a smart pig and incompletely inspected had failed. Operator error, improper training of pipe inspection personnel, and sloppy pipeline integrity procedures was blamed as the cause of the rupture but smart pigs proved to be accurate in finding serious corrosion damage that previous CIS had failed to find due to a rock shielding Cathodic protection current.
Both incidents proved the value of smart pigs and the limitations of CIS. In the NTSB report which covered both failures, CIS was clearly documented to be detective in finding serious corrosion damage if shielding issues existed. Smart pigging was promoted as a solution to the limitations of CIS. In addition NTSB did a survey of Kentucky pipeline operators as to how common natural gas pipeline ruptures due to external corrosion occurred. All natural pipeline operators reported that ruptures due to external corrosion damage were rare.
The tendency of cathodic protection companies is to assume that a major news making event such as a natural gas pipeline rupture due to external corrosion will result in more business for them. Typically the news story on a natural gas failure is that the pipeline operator had not upgraded the pipeline for the running of smart pigs and if the operator had run a smart pig the failure should not have happened. Typically cathodic protection budgets are not increased for the doing of CIS after a major pipeline failure due to external corrosion; but smart pig budgets are increased for the modification of pipelines to run smart pigs. The recent West Virginia natural gas rupture due to external corrosion is yet another example of if the pipeline operator had only upgraded the pipeline for running a smart pigs this could have been prevented. If the salespersons marketing CIS have not noted the news stories on the recent external corrosion rupture that sound like all newspapers are marketing smart pigs without a sales commission; they are in a state of denial of reality.
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