In response to a construction worker’s death at a Berkeley middle school, a California agency for worker safety is investigating the circumstances surrounding the incident.

Last Tuesday, Oscar Marquez was killed by a big rig while laying asphalt on the new track and field at Martin Luther King Jr. Middle School in North Berkeley. He was pronounced dead on site about 12:45 p.m.

The California Occupational Safety and Health Administration’s investigation of Marquez’s death could last up to six months, said Cal-OSHA spokesperson Peter Melton. Marquez had worked for Robert A. Bothman Construction Inc. for about 25 years.

“Inspections and investigations are very thorough, so they need time to make sure they get everything right,” Melton said.

He said the big rig that crushed Marquez may have been located on a slope, but the exact details of the case are still under investigation.

If found responsible for the accident, the company may be issued citations and forced to pay penalties.

Rosa Marquez, Marquez’s granddaughter, feels that closure will help her family move forward.

“I don’t want anyone to get blamed for it or anything — just to find out what happened,” she said.

During an investigation, Cal-OSHA safety inspectors look at records, go to the scene and interview employers, employees and eyewitnesses, Melton said. They also may inspect any machinery, such as the big rig that was involved in the incident.

Citing the ongoing investigation, the Berkeley Unified School District and the construction company declined to comment.

At the time of the incident, many people were on campus because a “Welcome Fair” was under way, said Christine Staples, the school’s PTA president.

“We’ve been so excited about having our new track,” Staples said. “It’s heartbreaking to have somebody lose his life in building it for us.”

Rosa Marquez remembered her grandfather as a religious, caring man and a loving father to his two children.

“(And now) I see how much people cared for him,” she said. “He was a really good person.”

Kristina Dodsworth-Heath, a mother of a sixth-grader at the middle school, said she hoped Marquez will be remembered. As a former construction worker, she empathized with manual laborers and called them the “backbone” of the community.

“I just know that the people on the campus are really sad for the family,” Dodsworth-Heath said. “I would want the family to know how aware the community is at the loss of his life.”

The construction company has established a fund for the Marquez family. A memorial service will be held at 2 p.m. on Saturday at Kingdom Hall of Jehovah’s Witnesses in Livermore.