The federal investigation into the deadly collapse of a Florida beachfront condominium building is entering a new phase that involves cutting and drilling into concrete and steel to determine what role they played in the disaster, officials said Wednesday.

The National Institute of Standards and Technology said in a news release that what’s known as invasive testing will begin soon as investigators seek samples from materials collected at the collapsed Champlain Towers South site.

“This is an important step in the investigation, one we are able to take only after months of careful investigation and preparation,” said Glenn Bell, co-leader of the investigation.

The tests will help investigators find potential flaws in structural elements of the 12-story building by looking into things such as density of the materials, how porous they were and if there was corrosion, NIST said.

The building in Surfside, Florida, collapsed without warning early on June 24, 2021, leaving 98 people dead. Legal settlements of more than $1 billion have been reached for families of victims and owners of the 136 units, with a key court hearing on approval set next Thursday in Miami.

The concrete, steel and other material from the collapse has been stored in a warehouse in Miami-Dade County, where it has been catalogued and used to create a 3-D model of the building, according to NIST. The materials will be moved out of the warehouse to an undisclosed location for the next phase of tests.

“The process of preparing the materials for the move and then securing them in their new location is expected to take several weeks,” NIST said in the release, noting that includes air sampling to detect harmful asbestos fibers.

Champlain South had a long history of maintenance problems and questions have been raised about the quality of its original construction and inspections in the early 1980s. Other possible factors include sea level rise caused by climate change and damage caused by salt water intrusion.

Florida will require statewide recertification of condominiums more than three stories tall under new legislation Republican Gov. Ron DeSantis signed into law last month in response to the disaster.

NIST also said investigators have developed a questionnaire for interviews of anyone who may have information about the collapse. This will be used in development of “failure hypotheses” the agency intends to analyze for possible causes.

Anyone with potentially relevant information, including photos and videos, can submit them through a NIST site. The agency has said it could take years to complete its investigation into the collapse.

(AP)