Transportation and Infrastructure Minister Glen Murray said he couldn't talk about the expert panel's report Tuesday because it's being reviewed by government lawyers and engineers.
"I gave a very strong assurance that before anybody ever uses any of this infrastructure — tunnels, roads or bridges — they will be safe," he said.
"They will be up to our standards and they will be signed off by the chief engineer of the province."
The report, which the government received Monday, will be posted online Wednesday morning, said Murray's spokesman Patrick Searle. Murray will be able to answer questions afterwards.
The minister ordered a stop to the installation of the girders in July and hired a group of experts the following month to conduct an investigation after questions were raised about whether the girders met the Canadian standards.
The government also closed a bridge in south Windsor on Aug. 29 based on information found during the review.
The girders will be removed if their safety and durability can't be assured and compliance concerns can't be addressed, the ministry said at the time.
In July, the ministry said about 560 girders were manufactured in a way that didn't meet the requirements of the federal bridge code. They were produced using tack welding, which isn't permitted under the code unless approved by the ministry.
Tack welding can be used to hold reinforcing steel in place while the girder is being manufactured and can weaken the reinforcing steel if not done properly, the ministry said at the time.
Of the 560 girders, about 320 were installed at two tunnels, the ministry said. One tunnel and three bridges that were already open to traffic were built with girders that met code requirements, they added.
The ministry became aware that the girders didn't meet federal code requirements in late 2012 and worked with Infrastructure Ontario to gather information and come up with a solution, officials said.
They said they first briefed Murray about the problem in June, four months after he was sworn in as minister.
Infrastructure critic Percy Hatfield, the newly elected New Democrat representing Windsor-Tecumseh, said he has a lot of questions about why it took so long for the government to halt construction once it knew there was a problem.
"This is the largest road-building project in Ontario's history," he said. "Where were the provincial inspectors during the construction period?"
If the girders need to be removed or replaced, taxpayers shouldn't have to foot the bill, he said.
A spokesman for Windsor Essex Mobility Group, which installed the girders, said it will review the panel's findings.
"We remain committed to resolving all outstanding questions and issues and ensuring that everyone can have confidence in the safety and durability of this infrastructure," said Joe Pickerill of Strategy Corp.
"We stand by our work and our workers unequivocally. We all want to get back to work."