On July 18th, a petroleum carrier was making a fuel delivery to the Gwinnett County Airport – Briscoe Field. During the delivery, a 10,000-gallon capacity jet fuel above ground storage tank (AST) began releasing fuel from the overflow value on the top of the tank. The fuel left containment and traveled 20 feet overland through a storm drain culvert to an underground municipal storm water system for approximate 1 ½ miles. The fuel left the storm drainage system and impacted approximately ½ mile of Cedar Creek and ½ mile of the Alcovy River. At this time, the facility is estimating that between 800 and 1000 gallons of fuel was spilled.