LNG expert says vapor model used inaccurately

A chemical engineering professor last week commented that the draft environmental impact statement for a proposed liquefied natural gas receiving terminal has inaccurate calculations for how far a vapor cloud could travel.

NorthernStar Natural Gas is planning to build a terminal at Bradwood, Ore., to receive shiploads of LNG. The plant would regassify the LNG and send it into pipelines. Critics have said an accident in the operation could create clouds of flammable gas that could endanger people as far away as Cathlamet.

In public meetings last week in Longview and Astoria, Dr. Jerry Havens of the University of Arkansas said that the Federal Energy Regulatory Commission (FERC) and NorthernStar Natural Gas have misused models he devised to calculate how far a vapor cloud would travel if LNG were spilled, the Longview Daily News reported last week.

Havens said that the data which FERC used assumes a relatively small spill, which skews projects for how far vapor rising off leading LNG could spread.

On pages 4-416 to 4-420 of the draft EIS, FERC predicted that the radiation from a fire would be largely confined to the site. In its prediction of vapor dispersion, FERC predicted that a vapor trail could reach the navigation channel in the Columbia, but there would be no prohibited land uses.

Haven said that the size of the projected spill in NorthernStar's data is smaller than spills projected in other terminal applications

While LNG spills are "highly unlikely," if an LNG fire engulfed the LNG tanker itself, there's a chance the fire could break open other containments on the ship and cause "cascading failures" in which case more LNG would be released, and "the whole thing would burn," The Daily Astorian quoted Havens as saying, citing a recent report from the Government Accountability Office (GAO). Havens made the statement while addressing Astoria city and county leaders at the Astoria City Hall on November 8.

NorthernStar said its LNG tanks will be double-lined and that the risk of a spill is minimal.

NorthernStar spokesman Joe Desmond called Havens a "professional opponent" and said the professor has given similar testimony on the applications of 14 different LNG terminals. In each case, Desmond said, Havens' arguments were rebuffed.

Environmental group Columbia Riverkeeper paid Havens' expenses to travel to Astoria, but Havens said he is not employed by the environmental group.