UNDERSTANDING AND CONTROLLING LANDFILL FIRES

Extinguishment Methods

Excavate and Overhaul:

Each excavator worked with a spotter throughout the fire fight.  Besides playing an important safety function, the spotter also used an infra-red temperature sensor to screen each bucket load placed in the truck (see Photo 10).  If all material placed in the truck was below 55ºC (122°F) the load was sent directly to the cold storage area.   If temperatures of one or more bucket loads were measured above 55ºC (122°F) then the load was directed to the hot pad for extinguishment.  Screening of excavated material reduced the amount of product needing extinguishment by approximately 45%.

 

Hot loads were transported to two large “hot pads” that were constructed on industrial properties north of the landfill where the burning material was spread out and foamed.  The hot pads, each approximately 75 x 100 m in area, were constructed using a 20 mil PVC membrane liner on top of a 300 mm sand cushion layer to prevent loss of leachate and contamination of the private properties temporarily expropriated during the fire fight.  A second 450 mm sand cushion layer was placed over the PVC to provide protection from above.  Lined ditches were constructed around the pad perimeter to collect leachate and convey it to a central sump.  Water collected in the sump was recirculated back into the fire hoses, thereby minimizing the amount of leachate needing discharge and effectively re-using the Class A foam additives.

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