Three bolts had no glue, Reilly says

Three of the bolts that were supposed to hold up the three-ton concrete panel that fell and killed a 38-year-old Jamaica Plain woman on Monday night have been found to have no epoxy on them, Attorney General Thomas F. Reilly said in an interview yesterday.

Reilly's investigation is focusing on whether the epoxy used in the tunnel failed , or if construction workers who installed the bolts misused or omitted the epoxy .

The epoxy, a high-strength glue, was used to bond the load-carrying bolts to the concrete roof in drilled holes.

``This is the most important evidence in terms of the investigation right now," said Reilly, who spent much of yesterday at the tunnel site after attending a memorial service for Melina Del Valle, who was killed in the ceiling collapse.

Reilly said that so far, investigators have found 19 of the 20 bolts that were supposed to have attached the concrete panel to the roof. He said the investigators are using the recovered evidence to ``recreate the positioning" of the panel in an area near the tunnel.

While some of the bolts appear to have no epoxy on them, others showed an uneven distribution of epoxy , Reilly said. Some of the bolts are bent, he said.

Reilly said last week as the investigation unfolded that the bolts that once anchored the panels slipped out cleanly, as the panels plummeted.

This suggested that the epoxy used had not bonded properly. His comments yesterday gave the most details yet concerning evidence that may illuminate the cause of the fatal incident.

After the accident, much of the construction debris was hauled out of the roadway, along with the car in which Del Valle was a passenger.

Del Valle's husband survived and climbed out of the vehicle. Reilly quickly opened a criminal investigation into Del Valle's death and since Tuesday has overseen the gathering of evidence.

Reilly said that while the epoxy is one focus of the investigation, the probe is much broader in scope and includes an examination of the design of the ceiling panel system.

Sean Murphy can be reached at smurphy@globe.com.