Feds release documents in investigation

For nearly a year, the National Transportation Safety Board has been investigating a March explosion at a West Reading chocolate factory that killed seven workers.

On Thursday, the agency shared with the public what it has found out so far about the deadly blast at the R.M. Palmer Co. plant.

The NTSB made public its docket of investigatory material, sharing it on the agency’s website. The docket includes 151 entries, ranging from interviews with public and Palmer officials to lists of chemicals that were in the building to fire drill records to maintenance reports.

The cache includes hundreds of pages of documents and dozens of photographs.

A social media post from the NTSB announcing the release of the docket said the investigation is ongoing.

The Palmer plant on South Second Avenue exploded just before 5 p.m. on March 24, leveling the building and rocking the borough. Emergency responders spent days sifting through the rubble, finding the bodies of seven workers who were killed in the blast, and one miraculous survivor.

In July, the agency released an updated preliminary report that a leak in a fitting on an out-of-use natural gas service line appears to be the cause of fatal explosion.

The preliminary report — the second the NTSB has so far issued — blames a fitting known as a service tee for causing a leak that led to the fatal explosion.

The service tee, which is a fitting used to make lateral connections, was installed in 1982 and retired by UGI Utilities in 2021 when the building’s natural gas meter was relocated from the building’s basement to a spot on its exterior, according to the report.

However, the tee remained connected to the natural gas system at full pressure and appears to have developed cracks that were leaking natural gas, according to the report.

The NTSB investigation doesn’t specify what is believed to have ignited the gas leak, but does offer some possibilities. It says the leaking 1982 service tee was located near a steam line, a condensate line and several heated chocolate pipelines.

The NTSB has not indicated when it will release a final report on its investigation.

To view the public docket visit data.ntsb.gov/Docket/?NTSBNumber=PLD23LR002.