MORE than 400 firefighters spent five days containing an underground fire near Neerabup Lake.
The peat fire started after lightning struck the area on Saturday, October 18.
The fire burned underground until flames broke through the surface about noon on October 21.
Wanneroo chief bush fire control officer Phil Hay said conditions were ‘very dangerous, extremely physically demanding and very tiring’.
‘Some spots are 1.7m of peat deep, under that is a clay soil that has acid in it, acid |sulphate, so it’s very acidic and produces a rotten egg smell ” it’s quite toxic,’ Mr Hay said.
‘We’ve got people who are falling into holes over a metre deep; it’s really uneven ground, the peat burns away and leaves the holes.’
Peat can smoulder for months and is known to be hard to put out.
‘We’re flooding the area with water and kill-fire, a biodegradable agent that penetrates the soil and peat, it smothers and suffocates it,’ Mr Hay said.
More than 5.4 million litres of water was used to contain the fire to a 3ha area.
All firefighters who attended were volunteers from brigades as far as Serpentine, Mundaring, Gosnells, Chittering and Kalamunda, with up to 60 on shift at a time.
Wanneroo, East Swan, Muchea and Quinns Rocks brigades also lent a hand.
‘I can’t speak highly enough of them and the huge effort they have put in; it’s the only reason we’ve stopped this,’ Mr Hay said.
‘We’ve had crews climbing in through bush and swamp, snakes going everywhere, falling into holes; they’ve just done a massive job.’
A police helicopter will continue to conduct patrols using infrared cameras to detect hot spots in the ground.
Firefighters will monitor the area three times per day over the next four weeks to ensure there are no flare ups.