• Editor’s Note: This editorial was changed on Aug. 11 to correct the cause of the fire in Ashland. It was not an explosion; the fire began in a chip grinder. It was the writer’s error.

 It could be coincidence, but it seems unlikely. The destruction of two rural Maine wood pellet manufacturing plants in less than five months should raise concerns about safety as this industry expands.

This past weekend, an explosion thundered through the new pellet mill in Strong, blowing apart its interior and sending, according to witnesses, a 200-foot ball of fire into the air. A neighbor told the Morning Sentinel the blast knocked an air conditioner out of his window.

In April, a pellet-making plant in Ashland burned from a fire in a chip grinder. Northeast Pellets was the state’s oldest pellet producer, dating back to 2005. 

Pellets are a growth industry for Maine. Gov. John Baldacci, just last month, toasted the announcement by International WoodFuels to build a $20 million pellet plant in Burnham, where the company has pledged to create 35 new jobs.

This trade is eyed as the perfect transitional industry for a rural state whose traditional resource-based economies, such as pulp and paper, has suffered. Not only does pellet-making require the same raw materials and skills as paper, but its purpose — heating fuel — has a strong market right here at home.

Proponents of pellets see them as an excellent opportunity for Maine to prosper economically, while also helping diversify the state’s home heating sources away from its petroleum dependence.

Plus, the infrastructure is ready for re-use. The pellet plant in Strong, for example, made toothpicks until its closure about five years ago. The one in Burnham is planned alongside a golf-tee plant.

These mills use materials unsuitable for other uses, though. They’re packed full of sawdust, piles of wood waste and heavy machinery — the perfect recipe for combustion, without even counting the high temperatures necessary for drying wood to make pellets.

In short, pellet mills require a great deal of energy to produce their product, in an environment where combustible materials are abundant. Other explosions in other pellet mills in this country and abroad have been largely attributed to combustible dust; a first thought in Strong was the same.

Dust explosions in pellet mills are all too common, according to the Combustible Dust Policy Institute (yes, there really is one). Its director wrote on an industry blog last year that 10 percent of Pellet Fuels Institute members on the East Coast had experienced a dust-related fire during just one three-month period in 2008.

As this industry grows in Maine, there should be confidence all safety regulations are understood, being followed, and every precaution is being taken. The explosion blew a 90,000-pound wood chip dryer off its foundation in Strong. It was lucky no one was hurt.

If that’s not cause for concern, then nothing is.

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