City will burn Hurricane Sandy debris — because it’s better for the environment!

The city will torch debris left behind by Hurricane Sandy instead of turning it into mulch because burning the lumber is more environmentally sound, officials decided on Tuesday.

The Department of Environmental Protection approved a variance this week to install as many as four air curtain burners at the greenspace that can light up toppled trees, allowing for the 24-hour, high-tech incineration of unwanted lumber from now until April 17 — despite concerns from neighbors and activists who fear the fire will damage air quality and hurt their lungs.

Environmental activists including the New York Public Interest Research Group, the Sierra Club, and the American Lung Association argued the fallen hardwoods would be better off sold as mulch, but authorities said turning the trees into ash creates less pollution than them into compost.

The reason why? Bugs.

To keep the ravenous Asian Longhorned Beetle — an invasive hard-shell pest known to attack maple, elm, willow, birch, poplar, and ash trees — from potentially compromising roughly half of the city’s five million trees, the lumber must be chipped or incinerated.

But in order to shred the wood in a way sure to eradicate any pesky insects, the city must feed wood through its chippers twice — each time creating harmful emissions from the machines themselves, the “fugitive dust created by the shredding process,” and the trucks that will haul the mulch to its final destination, according to a variance memorandum sent from Department of Environmental Protection commissioner Carter Strickland to a contractor.

A November test-run led the city to conclude that burning unchipped wood in the shipping-container-sized furnaces for 24 hours per day, seven days per week “would not have a significant impact on air quality in surrounding communities at ground level,” according to the report.

A diagram included in the city’s memorandum showed low levels of pollutants reaching the Marine Park Golf Course, Mill Basin, and the Toys ‘R’ Us on Flatbush Avenue, and slightly higher levels at the Aviator Sports and Recreation complex.

But New York Public Interest Research Group senior environmental associate Laura Haight says the city is grossly underestimating the amount of emissions created by burning the wood — and claims the practical applications of chipped wood more than make up for the added cost of eradicating the Asian Longhorned Beetle.

“Much like burning coal, this variance is going to allow for increased air pollution which can make people sick and send them to the hospital,” said Haight, who fears the incineration may bring an affliction called “Rockaway cough” to some of Brooklyn’s Hurricane Sandy-battered neighborhoods. “We’re talking about concentrating more pollutants in areas that are already suffering from mold and dust.”

And she says the city wouldn’t struggle to find buyers for the double-chopped wood.

“There’s a very robust market for wood chips,” she said. “From the get-go the city has been heavily leaning towards these burners.”

Reach reporter Colin MIxson at [email protected] or by calling (718) 260-4514.