Their concern was not the eyesore at the base of the Platt Memorial Bridge that has vexed the city since President Lyndon B. Johnson's motorcade paraded by from the airport in the 1960s, but the sound and vibrations.
And so, it was kids vs. car crusher as about a dozen children formed the focal part of the four dozen protesters, whose rallying cry is "Stop the Boom" (#stoptheboom on Twitter).
"The home shakes, you just feel it," said Natalie Calabrese, 10, whose propped-up wooden sign read "Honk to Stop the Booms."
The adults say the problem seems to have escalated recently, and that the company - which predates the arrival of families and developments near FDR Park - has yet to adapt.
"The area has outgrown them," said resident Andrew Rosser. "It's truly at the level of an earthquake."
Nan Feyler, chief of staff for the Department of Public Health, said inspectors conducted overnight surveillance outside the plant this week and issued four noise violations.
She said the company's permit would not be renewed unless the violations are resolved and the company puts procedures in place to end noise violations.
The neighbors, along with City Councilman Kenyatta Johnson and State Rep. Maria Donatucci, became alarmed when the company requested a renewal of its air management permit, set to expire this July. They said they had believed, based on past statements by company president Joseph Balzano, that the company had been planning to move all its operations to Camden, where it has headquarters.
An earlier plan, backed by then-Gov. Ed Rendell, to consolidate the company's operations on a new pier in Eddystone, Delaware County, fell through when his successor, Gov. Corbett, withdrew $31 million in financing.
Balzano said Wednesday that the Camden plan was never going to be a full consolidation like Eddystone. He said he was upset that he spent millions on the Eddystone plan only to have it fall through.
Now, he said, he is working on a new, quieter shredder to be installed in Camden. He had projected it to be completed by now, but set a new goal for May or June.
He said the result of moving more of the operation to Camden will be a quieter operation in Philadelphia, but added that competitive concerns will keep at least some operations here.
Balzano said he had arranged a meeting with neighbors for Feb. 24 and was puzzled that the protest and complaints boiled over this week.
The noise standards have always been there, but until about eight years ago, nobody was around to complain. Donatucci said she thought the explosions were from propane tanks or gas left in cars that are brought to the plant, which could be solved by going through the cars first.
Balzano said he was trying to stay within the code, but feels blamed for "every sound in South Philadelphia."
"I know it's not a pretty business, but it's a necessary business," he said, noting that his company employs nearly 400 workers, Teamsters with health benefits and union wages. "We've been there for 35 years and never had these issues. People build houses all around you, and now it's become this issue."
Contact Amy S. Rosenberg at 215-854-2681 or firstname.lastname@example.org. Follow on Twitter @amysrosenberg.