Foam Averts Spill Disaster
A disaster was averted when an 8000-gallon tank truck spilled 2700 gallons of high-test gasoline on the grounds of a large suburban shopping center in Wayne, Pa.
The Gateway Shopping Center is at the intersection of Route 252 and Route 202 Bypass. The center is typical, with numerous stores, a movie theater, a restaurant and a large grocery store. It is bordered on the south by Route 202 Bypass and on the west by Route 252.
Route 202 Bypass is a four-lane, limited access highway, and at 9 p.m. last June 19, a Saturday, it was heavily traveled by both cars and trucks. The center had a large number of patrons because of the theater and restaurant. The weather was clear, with a light breeze from the west. The store in the center nearest the spill was 500 feet away, and the theater and restaurant were about 1000 feet distant.
The tank truck was parked on the shoulder of the Route 252 exit at the southwest corner of the center. A new tractor had just been connected to the trailer and, after pulling away about 100 feet, the trailer became disconnected from the fifth wheel and fell on it. This caused a large split in the underside of the first of three compartments. The entire 2700 gallons of gasoline in that compartment spilled out. Fortunately, the other two compartments remained intact.
The Berwyn Fire Company responded to a report of a gas spill with Chief Frank Kelly in charge. The spill was in a ditch 3 by 150 feet, along the southwest edge of the shopping center, and the breeze carried the fumes toward the east end of the center, which included the theater and restaurant. Kelly recognized that this problem was two-fold—avoidance of fire and removal of the hazard.
All highway approaches to the spill area were closed. Berwyn’s 1000-gallon pumper stretched a 2 1/2-inch line from the spill area to a hydrant 500 feet away. The Radnor Fire Company responded with a 1000-gallon pumper and the Paoli Fire Company with a rescue truck.
Two types of foam used
The initial approach was with protein foam. The spill area and the tank truck were covered with a 2-inch blanket of protein foam. Then the spill area was covered with an additional 2 to 3 feet of high expansion foam. The breeze had no effect on this blanket of foam.
When this application of foam was completed, two tow trucks were brought in to lift the front end of the trailer to permit the tractor to reconnect securely. Three charged lines, one 2 1/2-inch and two 1 1/2-inch, stood by at this time.
After the tractor was reconnected to the trailer and driven away, an additional 1 foot of high expansion foam was spread over the entire spill area. A total of 70 gallons of 3 percent protein foam and 15 gallons of high expansion foam were used in this operation.
An examination of the area the next morning showed traces of high expansion foam still in place and only a heavy residue left from the gasoline.