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As the fire progressed, firefighters and first responders also came from Hadley, Belchertown, Northampton, Leverett, Shutesbury, Sunderland, Pelham, South Hadley, South Deerfield, and Granby. Some communities sent tanker trucks and helped in a next-day task force watering down the fire. Preparedness is part of the job for any firefighter, but the reality the Amherst Fire Department encountered on Friday was daunting, said assistant fire chief Steven Chandler on Monday in his office at the downtown station. (The two assistant chiefs are sometimes called “the Steves.”) He was hoarse from shouting over fire engines in the rain, and from the cold he came down with over the weekend. The fire ultimately led to the total destruction of two adjacent structures — one, on a construction site at 47 Olympia Drive; the other, an occupied residential building at 57 Olympia Drive — that are privately owned by Archipelago Investments LLC and located across the street from UMass Amherst. The blaze was first called in to 911 at 8:19 p.m. Friday, and “the initial crews reported that they could see fire from the fire station,” said Chandler. By the time they pulled up to 47 Olympia, the site of the new construction, it was consumed by flames and collapsing. Meanwhile, the fire had begun to spread to the occupied building, forcing an evacuation. “We had two building fires at the same time, which is a challenge — both with personnel deployment and with water,“ said Gaughan. On Saturday, the town of Amherst declared a state of emergency, and the fire chief determined demolition was the only way to control the fire. Many questions linger. “We don’t know the ‘how,’” said Chandler, noting the cause of the fire is under investigation. “What I can tell you is: The occupied residential building was sprinklered, and if a fire had started in a room in that building, it’s likely that a single sprinkler head would have activated and kept that fire in check,” he said. “But when you have a construction site next door that doesn’t have fire protection, doesn’t have a sprinkler system yet, doesn’t have any of that stuff — it’s just basically a lumberyard that gets going ... and is letting off that much radiant and convected heat — it overwhelmed the sprinkler systems and our efforts in the building that was right next to it.” It also triggered multiple explosions believed to be from fuel tanks on the construction site and one crane collapse. High winds and low water pressure foiled the firefighters’ efforts to stop the flames from spreading, but no one was injured. The crews also went back and rescued three cats, said Chandler, noting they later found out other pets were also in the building and likely died in the blaze. After the first alarm, a second and third one were sounded for mutual aid. Among the helpers: student firefighters from the University of Massachusetts Amherst Student Force. Students helped hook up hoses to fire hydrants but didn’t run into the burning building. “The magnitude of this fire was significant, and it does reach a point where they are kids, right? They’re college kids, they’re 18, 19 years old,” said Gaughan. “Some of our deployment is based on that. Many people in here have never seen a fire of this magnitude and this much destruction and as much fire — the volume of fire was very significant. “It was obviously eye-opening for these students,” he said, emphasizing how hard they worked over the weekend. The site of the former Olympia Place complex was reduced to rubble and charred remains. Chandler’s business card stuck to the wet pavement near a group of firefighters spraying down possible hotspots on Monday. “Your safety is our business,” it read. “I actually got quite a bit of time to talk to residents,” said Chandler. “Everyone has been remarkably understanding. You know, a lot of these students lost everything that they own, and yet they come up and they say, ‘Thank you for all your efforts, and we’re just glad nobody got hurt,’ which is our opinion as well. “It’s easy to say it’s just stuff, but it’s their stuff. It’s all of their stuff,“ he said. “The inability to get them back in to clear their rooms is something that we all regret, but unfortunately, it wasn’t safe enough for us to be in there to fight fire.”