A contractor has resumed clean-up work at the former Sequens pharmaceutical plant in Newburyport, Massachuetts, officials said Tuesday afternoon.
The project is being supervised by local, state and federal authorities.
"There are two large vats of chemicals that need to be drained, and several more barrels that need to be removed. The two chemicals in the larger storage containers cannot come into contact with one another, so the process continues at a careful, methodical pace," Newburyport Fire Chief Stephen Bradbury said in a press release.
Last week's explosion at the Seqens plant tore the roof off the building and sprayed debris as far as 800 feet from the facility. One worker was killed and four others injured in the blast. The person who died was identified as Jack O’Keefe, 62, of Methuen, according to the Essex County District Attorney’s office.
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Work was temporarily halted at the Sequens site as a precaution on Monday after high winds caused the metal building's walls to shift.
What remains of the building is being supported by a large crane. During a meeting between fire, hazmat and building officials on Tuesday morning it was decided that conditions were safe enough for work to resume.
Demolition of the building is now expected to begin on Wednesday, officials said.
The explosion happened around 1 a.m. on May 1, officials said. Video showed most of the roof torn off a building, marking at least the third safety problem at the plant since 2020.
Smoke from the fire blew into a largely unpopulated area, according to the state Department of Environmental Protection, and air quality monitoring near the site has so far detected no hazards. Area waterways are also being monitored.
The plant lies a little more than 30 miles north of Boston and has had a string of problems over the years - prompting U.S. Sens. Edward Markey and Elizabeth Warren of Massachusetts and U.S. Rep. Seth Moulton — in whose district the facility is located — to write a letter to the company late Thursday demanding a full accounting of what happened.
“This explosion is only the latest avoidable disaster at this facility, following years of serious safety violations, multiple fines, and other explosions,” the lawmakers said in the letter. “We write seeking the explanation as to why this latest incident occurred and how, after years of fines and regulatory enforcement actions, Seqens could have allowed unsafe conditions to persist.”
Thursday’s explosion makes it “painfully apparent that your company has failed to create any meaningful or effective safety culture,” the letter said.
Sequens said in a statement last week that it is focused on employee safety. "We strive to follow best practices and regulatory guidelines, and have implemented safety protocols and procedures to prevent incidents like this from occurring."
A chemical fire in the building in June 2021 sent smoke pouring out of roof vents and prompted a hazardous materials team to respond, according to a fire department statement at the time.
In 2020, authorities said a chemical reaction caused a series of explosions at the plant. That happened a year after the Occupational Safety and Health Administration found “serious” violations in how the company managed highly hazardous chemicals, according to online agency records.
The factory has also been cited by OSHA for workplace safety violations and in 2019 paid a penalty of more than $50,000 to settle Environmental Protection Agency charges that it violated hazardous waste laws.
The Associated Press contributed to this report.