By JOSEPH B. NADEAU

WOONSOCKET — For the last few weeks, a crane and several large excavators have been slowly chewing away the old brick mill buildings off Hamlet Avenue and Florence Drive that were once part of the Layfayette Worsted Mill complex.

The pace of that demolition shifted into a higher gear as David Evans of New Jersey arrived at the site early Friday morning, bringing along his own techniques for clearing away the old to help make way for the city’s new $80 million middle school complex.
Evans is an explosives demolition expert who was hired by Gilbane Construction to take care of two large and troublesome features of the old mill still rising tall from the site in the early morning sunshine.
Evans’ task: raze the masonry smokestacks that were remnants of the large mills constructed almost a century ago. The bulk of the buildings had already been taken down by Gilbane’s demolition contractor, A.A. Wrecking of Johnston, and a mill fire there several years ago.
A.A. Wrecking considered pushing the stacks over with one of its pieces of heavy equipment, but opted for Evans’ talent as a better way to level them.
“It brings it down and it brings it down in a way where it doesn’t hurt anyone or anything,” Evans said of his work. “That’s the goal we try to achieve.
One of the stacks Evans was contracted to remove, a brick structure with the words Lafayette Mill inlaid on its top section, rose 150 feet above the property and the other, a terra cotta structure, rose 175 feet.
Trying to drop either of those structures with an excavator or crane could have been very dangerous to the equipment operator, he said.
 “If you tried to pull that down with a backhoe you would be going to a funeral,” Evans said.
Using explosives, the contractors could topple the structures with everyone a safe distance away, finishing the job in a jumble of bricks when it was all over just after 1 p.m.
 “The main thing is the perimeter,” Evans said while pointing to the effort coordinated among city police, fire and engineering departments to secure a proper buffer zone around the construction site for the two blasts.
Police closed off Villa Nova Street on one side of the site, all of Florence and a section of  Hamlet Avenue just before the explosives were fired.
Evans and his crew of about a half dozen technicians had spent the morning filling holes drilled in the bottom of the stacks with sticks of dynamite, then connecting the wiring that would set them off in separate blasts for each structure. The same techniques could not be applied to the mills themselves because of all the wooden beams used in their construction, Evans said.
“You use explosives on a wood structure and you get a fire,” he said.
After the charges had all been set Friday and a protective barrier was installed around the base of the stacks, Evans and fire and police officials held a final meeting to ensure the buffer zone had been cleared and everyone was ready.
 After getting the go-ahead, Evans set the blast time and began his countdown.
A premonitory siren blast signaled five minutes until boom time. followed a longer siren warning sounded just before the shot.
The brick Lafayette stack went first with a burst of fire and brown smoke erupting like a halo around its base. The structure then sagged and collapsed straight downward as it disintegrated into the individual bricks left when the smoke cleared.
The second blast at the base of the newer looking terra cotta stack felled it whole like a tree, falling over to one side initially, then also disintegrating into rubble before hitting the ground.
Acting State Fire Marshal Leroy Rose, watching the demolition with Deputy State Fire Marshals Richard James, said Evans had delivered on the blasting plan he had submitted to state and local officials.
“It was done safely and professionally,” he said as Gilbane’s excavators began removing the two piles of brick from the site.
Gilbane’s project managers, Jeff Wolstencroft and Aleita Hall, said the quick removal of the smokestacks would allow the company to finish clearing the site by June 1 as planned under the construction schedule. That would in turn set the stage for environmental clean-up on the former mill property, to be followed by footing and foundation work for the planned 880-student schools.
“I’m just anxious to get started on the construction phase,” Hall said. That work, the erection of steel, should be starting around September if all goes well, she said.