ST. PAUL, Minn. — A legislator wants a chunk of the collapsed interstate bridge to remind him of the dangers of neglected infrastructure. Survivors have sought the crumpled steel as mementos of that deadly day in Minneapolis six years ago on Thursday. Civil engineering instructors and historians see value in the wreckage, too.

In a few weeks, Minnesota Department of Transportation officials will begin parceling out tons of steel from the Interstate 35W bridge, which collapsed during rush hour on Aug. 1, 2007, killing 13 people and injuring 145 others.

Some nine million pounds of rusting, lime-green steel are spread across two storage facilities, and it will be distributed under a law approved this spring. Whatever isn't claimed by Thanksgiving will be sold for scrap, potentially netting more than $500,000.

It's a closing chapter in a saga that began when the busy eight-lane bridge suddenly buckled on a muggy evening, sending dozens of vehicles crashing into the Mississippi River and each other, and stirring ripples of worry about the nation's aging infrastructure. Investigators blamed a design flaw that was exacerbated by extra weight from a resurfacing project.

"Anybody who was on that bridge when it fell or had family on that bridge when it fell will get some steel if they want," MnDOT spokesman Kevin Gutknecht said.

State Bridge Engineer Nancy Daubenberger wrote to collapse survivors and victims' families in May to inquire about interest in obtaining salvaged bridge parts. She said Wednesday that 30 to 40 people have stepped forward so far to ask to reserve about 75 pieces.

When distribution starts in late August or early September, people can choose among bolts the size of a pen or opt for larger hunks, including some a couple feet long that weigh as much as 100 pounds. They will get them free of charge, but they must retrieve them and sign a liability waiver given sharp edges and lead-based paint.

One collapse survivor, Brent Olson, first approached state officials years ago about letting those affected by the tragedy have a chance to claim bridge parts. He was told he'd have to wait for the lawsuits to conclude because the old bridge was considered evidence in a possible trial.

Since then, he rounded up almost 20 requests from people wanting small keepsakes or larger sections to use in personal memorials in their yards.

"With or without a piece of the bridge, it's going to be with us the rest of our lives," Olson said. "I can think about it and not get emotional. Is the piece of the bridge going to maybe expand that feeling? I don't know."

Olson was headed across the bridge that August evening on the way to a Minnesota Twins baseball game with his wife to celebrate their 38th anniversary. They escaped serious injury, but Olson thinks about it often. He intends to display his steel piece on his fireplace mantle or in a shadow box near other tributes in his home.

Parts will also go to the Minnesota Historical Society, the National Transportation Safety Board and college civil engineering institutes that want pieces as teaching tools.

Democratic state Rep. Ryan Winkler also hopes to secure a piece of steel for his office. An attorney, he helped fashion a state settlement fund the year after the collapse and sponsored the law that will guide the steel distribution.

"It's something that we need to remember," said Winkler, of Golden Valley in suburban Minneapolis. "Having a piece of the steel will be a reminder to public officials of the need to take care of public safety."

Similar sentiments are behind a request from outgoing Minneapolis Mayor R.T. Rybak's office for a piece of the wreckage. The city itself is also in line for steel.

"It was absolutely a defining point for the mayor professionally and personally," said Rybak spokesman John Stiles. "He went to every funeral. He sat for hundreds of hours with survivors. It was very personally meaningful."

MnDOT also will keep pieces. Some will be at the agency's bridge office to remind engineers of their important role. Other parts could be on display in an atrium at the Transportation Department's headquarters next to the Capitol, said Daubenberger, the state bridge engineer.

Beyond a few groups of recipients spelled out it the law, the agency has discretion about who can have a remnant. Daubenberger said some survivors have asked the department to closely adhere to that limitation.

"They have expressed to me that they do want to make sure that the distribution of this steel is kept to those directly affected," she said.

There will be tough calls for officials to make.

The Lake Region Pioneer Thresherman's Association has asked for a giant roller bearing part from the bridge to display alongside its old tractors, steam locomotives, log school building, saw mill and other past-century features on land in Dalton, Minn.

The nonprofit association's president, Richard Akerman, said it would give the thousands of visitors who come by annually a chance to see the part up close and better understand how older bridges function.

"We would certainly not be sensationalizing in any way the tragedy there," Akerman said. "That's not what we're about. We're about preserving the past for future generations. That's our goal."