scope:

Description of Driving Event:

On July 13, 1988, hydrazine was being transferred from partially filled drums into LT-44. There were seven drums for a total of 343 gallons. Adding the 134 gallons in LT-44 resulted in 477 gallons - well within the tank's 500 gallon capacity. As the hydrazine was being transferred from the last drum, a mechanic saw liquid spray from the vent hose and immediately closed the vent and fill valves. After securing the area, mechanics reported that all the flags at the top half of the LLI indicated the tanker was full. This suggested the magnetic liquid level gauge's reliability is questionable due to erratic operations.