The National Transportation Safety Board has released their final report on the June 10, 1999 Bellingham, Washington pipeline accident. It can be downloaded from: www.NTSB.gov/Publictn/P_Acc.htm. This accident has been a major factor in the subsequent Pipeline Integrity Management rulemakings for liquid pipelines. The NTSB’s executive summary states: The Safety Board determines that the probable cause of the June 10, 1999, rupture of the Olympic pipeline in Bellingham, Washington, was (1) damage done to the pipe by IMCO General Construction, Inc., during the 1994 Dakin-Yew water treatment plant modification project and Olympic Pipe Line Company’s inadequate inspection of IMCO’s work during the project; (2) Olympic Pipe Line Company’s inaccurate evaluation of in-line pipeline inspection results, which led to the company’s decision not to excavate and examine the damaged section of pipe; (3) Olympic Pipe Line Company’s failure to test, under approximate operating conditions, all safety devices associated with the Bayview products facility before activating the facility; (4) Olympic Pipe Line Company’s failure to investigate and correct the conditions leading to the repeated unintended closing of the Bayview inlet block valve; and (5) Olympic Pipe Line Company’s practice of performing database development work on the supervisory control and data acquisition system while the system was being used to operate the pipeline, which led to the system’s becoming non-responsive at a critical time during pipeline operations.
The major safety issues identified during this investigation are as follows:
- Excavations performed by IMCO General Construction, Inc., in the vicinity of Olympic’s pipeline during a major construction project and the adequacy of Olympic Pipe Line Company’s inspections thereof;
- The adequacy of Olympic Pipe Line Company’s interpretation of the results of in-line inspections of its pipeline and its evaluation of all pipeline data available to it to effectively manage system integrity;
- The adequacy of Olympic Pipe Line Company’s management of the construction and commissioning of the Bayview products terminal;
- The performance and security of Olympic Pipe Line Company’s supervisory control and data acquisition system; and
- The adequacy of Federal regulations regarding the testing of relief valves used in the protection of pipeline systems.