An internal company report on the Longford, Vic., gas processing plant disaster, by Exxon Corp. has found that a detailed hazard operability study might have identified the hazard associated with low-temperature liquids in the bottom of the plant.
Employees of Exxon unit and plant operator Esso Australia Ltd. recently testified at a Royal Commission review of the accident, which cut gas and oil supplies from Australia's Bass Strait last September, saying that a heat exchanger ruptured after becoming frosted over with ice (OGJ, Jan. 25, 1998, Newsletter). The commission review has been extended and is now expected to last until midyear.
Internal reportDuring the commission hearings, a subpoenaed internal company report concluded that Esso did not conduct a detailed hazard study on the section of the plant that exploded and caught fire and cited this as a possible reason for the disaster. The report was written by visiting Exxon specialists and referred to by the company as an "interim" report and just one of a number of reports that will be tabled at the inquiry.
The report authors said that a detailed plant hazard operability study would most likely have identified the potential hazard. They also concluded that an automatic protective system for low temperatures in the plant may have prevented the incident, but industry practice during the 1960s, when the plant was built, did not require such devices.
The report also said that staffing and maintenance levels were checked to gauge their effects on the incident, but neither was identified as a contributory factor. It found overall procedures and training at Longford were effective. The report noted that Esso identified and assessed 390 risk scenarios for its offshore and onshore operations in the area.
In other recent submissions to the commission, Esso has mounted a counterattack by saying that the Victorian government should be investigated over whether it failed to provide alternative gas supplies to the state.
Meanwhile, oil production from the Bass Strait fields, shut in for more than 2 months immediately after the incident, has now returned to more than 200,000 b/d.
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