A complete shutdown of Dakota Gasification Co. near Beulah stretches into its third week with no start-up date yet announced.

The behemoth synthetic natural gas plant was shutdown Dec. 19, when workers discovered a crack in a major vessel containing phenolsolven, a dangerous chemical.

The plant normally manufactures around 150 million cubic feet daily of the gas and each day of lost revenue is in the range of $1 million.

Plant spokesman Daryl Hill said the cracked portion of the phenolsolven vessel was cut away and has been shipped to a metallurgical laboratory for study.

The lab specialists should be able to say why the vessel failed and how to fix it, Hill said.

A date for restarting the plant will depend on what the fix requires, he said.

This is the first unplanned complete shutdown of the plant in its 20-year history.

The synthetic gas is produced on two separate production trains and normally one can run if the other develops problems and needs to be shut down for repairs.

In this case, the phenolsolven vessel and storage area is common to both production trains.

DGC was completely shutdown three years ago, when it went on "black plant" status in order to conduct top to bottom maintenance.

Hill said the plant's 600-plus employees are doing other maintenance work during the shutdown, and it's not expected that any employees' shifts will be curtailed in the meantime.