Officials from the U.S. Chemical Safety Board were allowed yesterday onto the explosion site off Water Street after being denied access for four days. At a morning meeting in the U.S. attorney's office in Boston, an agreement was struck between the state fire marshal, state police fire investigators, the Bureau of Alcohol, Tobacco, Firearms and Explosives, the Danvers Fire Department and the Chemical Safety Board.

"All parties have agreed to cooperate in executing their different missions," said a joint statement issued after the meeting.

State Fire Marshal Stephen Coan said Monday the Chemical Safety Board was barred from the site because it was still a possible crime scene. Yesterday's agreement permits the board's investigation to coincide with the criminal one.

"The CSB and ATF will coordinate to ensure the integrity of the ongoing civil and criminal investigations during the access to the site," the statement said.

Coan said a final determination about whether the explosion was a crime or an accident could come as early as today.

"We're very pleased that our authority and jurisdiction has been recognized," said Daniel Horowitz, spokesman for the Chemical Safety Board.

The Chemical Safety Board is a Washington, D.C.-based federal agency that investigates chemical accidents and makes recommendations to prevent their recurrence. Its authority is derived from the federal Clean Air Act.

Horowitz said six investigators will be on the scene today identifying and documenting evidence, and two more will arrive by tomorrow. "We're sorry for the delay, but we're happy to be there. We'll see what the conditions are."

Coan said the board's expertise will be a valuable asset. "The Chemical Safety Board has an important role to play in a successful outcome to this investigation."

A week after a massive explosion rocked Danversport, Coan said his investigators could wrap up work at the scene today. "The investigators had another good day," he said yesterday. "They made good progress."

Two more families moved back home yesterday, bringing the total up to 14 since Sunday. Town Manager Wayne Marquis said another four or five families remain "a step away" from going home.

About 50 families remain displaced from homes in the area of Bates and Riverside streets, the section of the neighborhood closest to the chemical plant.

Homeowners yesterday continued their slow trek back to normal life. Many have accepted that it could be months before they can return home.

"I'd be optimistic to say it's a few weeks off," said Amy Goodnow, while standing outside her home at 16 Riverside St. She's weighing whether it makes more financial sense to repair her house or tear it down and rebuild.

"I think I'm going to save it, but I guess I can't be sure right now," she said.

Janet Lettich of 12 Riverside St. expects she won't be back into her home until spring. Until then, her family will stay in an apartment in downtown Danvers.

Plywood still covers the doors and windows of the homes along Bates and Riverside streets. In a resilient recognition of the holiday season, one resident hung a wreath on the piece of plywood doubling as her front door.

Since the explosion, outside traffic has been directed away from Danversport. The kids who used to fill the neighborhood are gone. Their basketball hoops are now used to string yellow police tape, their bicycles abandoned on front porches.

The bustle of everyday life has been replaced by a steady stream of contractors, insurance adjusters and building inspectors. At night, the floodlights positioned throughout the neighborhood light it up like a movie set. Police patrol the streets and guard against the threat of looting.

Marquis said the town has rented a trailer that will be stationed in the neighborhood for at least three months to help expedite the permitting process.

So far, he said, Danvers has spent more than $250,000 to respond to the disaster. Marquis is hopeful that cost could be covered by insurance or a special act of the state Legislature.

"People have pulled together, and I'm just very pleased and proud of the way (town) employees and volunteers have responded," Marquis said.

Up in his office, Marquis has a poster of Danversport that shows all the affected homes. He closes each day by putting a green thumbtack on those homes in which people have returned. Yesterday, he let Building Inspector Richard Maloney do the honors.

"That's kind of the highlight of the day," Marquis said.