News Release September 14, 2001
FOR IMMEDIATE RELEASE
EUB INVESTIGATION REPORT - KEYSPAN STRACHAN GAS PLANT FLARING INCIDENT
Calgary, Alberta (September 14, 2001) The Alberta Energy and Utilities Board (EUB) has completed its investigation into two gas plant flaring incidents in the Rocky Mountain House region of west central Alberta. The two flaring events occurred at the KeySpan Strachan Gas Plant, approximately 20 kilometres southwest of Rocky Mountain House on January 23 and 25, 2001. The first event on January 23 was caused when a backhoe operator working on another property accidentally cut the main power line to the plant. This required an emergency plant shutdown and subsequent start-up. This resulted in approximately 90 thousand cubic metres (three million cubic feet) of gas being flared, with a hydrogen sulphide (H2S) concentration averaging 17.3 per cent. The second event occurred January 25 when a gas sweetening process pump failed. This resulted in just over one million cubic metres (37 million cubic feet) of gas with a maximum H2S concentration of 0.01 per cent being flared until the plant restored its capability to process gas to sales specifications of zero H2S content.
As a result of this investigation, the EUB believes that KeySpan responded to both incidents in a timely and professional manner. However, for the January 23 event, KeySpan cut fuel gas to the flare system while the acid gas meter was still showing a flow rate. This resulted in a noncompliance with EUB requirements. The EUB expects that fuel gas to a flare system will be controlled so that a heating value of 12 megajoules per cubic metre of flared gas is met and ambient air quality guidelines at ground level are not exceeded.
The EUB investigation found that emissions monitoring during the January 23 event showed two one-hour exceedances of 12 parts of H2S per billion parts of air recorded at a Keyspan stationary air monitoring trailer located 4 kilometres northeast of the plant. These exceedances were likely due to not adding sufficient fuel gas for the entire period that gas was flared. The Alberta Ambient Air Quality Guidelines limit is 10 parts of H2S per billion. The EUB regards the failure to add sufficient fuel gas to the acid gas flare as a major level-2 noncompliance event.
KeySpan was directed to develop written operating procedures for plant staff to follow in the event of similar events at the Strachan gas plant or other associated facilities. These procedures have been developed and reviewed with KeySpan's operating staff. Copies of the procedures were submitted to the EUB and have addressed the EUB's concerns. The EUB will audit future flaring events at the Strachan plant to ensure that the commitments made by KeySpan are adhered to. There were no contraventions associated with the second flaring event, which occurred on January 25.
This news release and a copy of The Keyspan Strachan Flaring Incident Report is available on the EUB Web site at http://www.ercb.ca
Greg Gilbertson, Senior Advisor
EUB Communications
Tel. (403) 297-3648
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NR 2001-35
