NEW YORK (CBSNewYork/AP)— While regulators fell short, three construction company supervisors are the ones to blame for two firefighters’ deaths in a condemned ground zero tower, prosecutors told jurors Wednesday.

By turning a blind eye to a break in an essential firefighting water pipe, “they did the thing that killed those firefighters,” Manhattan Assistant District Attorney Joel Seidemann said in a closing argument at the manslaughter trial stemming from the August 2007 fire at the former Deutsche Bank building.

“The evidence … woven together, paints a mosaic of overwhelming guilt — that but for these wholly reckless acts, these firefighters would be alive today,” Seidemann said.

Jeffrey Melofchik, Salvatore DePaola, Mitchel Alvo and the John Galt Corp. are charged in the only criminal case resulting from the fire. Alvo and DePaola worked for Galt.

Defense lawyers have said the men didn’t realize the pipe’s significance and are being scapegoated for government agencies’ and companies’ mistakes in overseeing the complicated project of dismantling the building. It had been damaged and coated with toxic debris in the Sept. 11 terror attacks.

“Nobody foresaw this perfect storm of terrible circumstances,” defense lawyer Edward J.M. Little said in a closing argument Tuesday.

After the blaze roared through nine stories of the tower and killed firefighters Joseph P. Graffagnino, 33, and Robert Beddia, 53, it emerged that the Fire Department hadn’t conducted required inspections for more than a year. A crucial firefighting water pipe, called a standpipe, had been broken for about eight months. With the standpipe hobbled, it took firefighters about an hour to get water on the spreading flames and choking smoke.

Meanwhile, building, environmental and labor inspectors hadn’t realized that some measures meant to contain toxins could thwart firefighting. Stairwell barriers slowed firefighters’ progress, and a fan system concentrated smoke.

The city and Melofchik’s employer, general contractor Bovis Lend Lease, acknowledged errors. In response, the Fire Department created dozens of inspection and auditing jobs, and Bovis agreed to finance a $10 million memorial fund for slain firefighters’ families, among other responses.

“I’m not going to get up here and argue that the regulation was great, the supervision was wonderful,” Seidemann told jurors. But, he said, the crucial failing came when workers, struggling to clean asbestos off braces that held the standpipe to the basement ceiling, took the supports down at Alvo’s and DePaola’s direction in November 2006. Alvo was Galt’s toxin-cleanup director, and DePaola a foreman.

Under pressure to speed up cleaning the contaminated building as expensive overruns loomed, “these defendants — all three of them — consciously disregarded the risks they were taking in an effort to get this job going,” Seidemann said.

After a segment of the standpipe clattered to the floor, Melofchik — the project’s site safety manager — came to the basement, prosecutors said. The three decided to get rid of some 42 feet of broken or precariously hanging standpipe and did nothing to fix it or point it out, though Melofchik kept signing daily reports saying the building’s fire-suppression system was working, prosecutors said.

Defense lawyers have said the men didn’t distinguish the standpipe in a web of pipes that ran through the basement, but Seidemann noted that workers have testified that the standpipe’s important role was known. Plus, Seidemann noted, the three men have decades of construction experience among them.

“They touted their experience level before this happened, and now that it happened, they know nothing,” he said.

If convicted, Melofchik, 49, DePaola, 56, and Alvo, 59, could face up to 15 years in prison. The Galt company could face a $10,000 fine.

After hearing about 10 weeks of testimony, the jury could start deliberating as soon as Thursday on the charges against DePaola and Melofchik. Alvo and the company have elected to have a judge decide their cases. She is expected to hear their lawyers’ closing arguments, plus more from prosecutors, next week.

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