Mark Harvey does not skimp on the details when describing the three trailers that have now become, almost, legend within his office at the Archives of Michigan.

Residing in knotted grass behind a machinist shop in Trenton, the trailers were leaning at all the wrong angles. Holes were ripped through the sheet metal. Because of mold and the raccoons that had nudged their way inside — leaving fecal matter and destruction in their wake — Tyvek suits and respirators were required to enter.

In short, it was sort of a disaster. Especially when considering the contents: thousands of documents, artifacts and detailed drawings that went into the construction of Detroit's iconic Michigan Central Station. Documents that were removed from the station by employees when the depot shut down in 1988, and then, over the course of nearly three decades, bounced around metro Detroit, swapping hands and locations as various guardians recognized they were holding onto something valuable, but just didn't know what to do with it.

"Mary, my colleague has said this," Harvey said with a laugh, recalling the mixed emotions they felt as they stood with the most recent caretaker — the one who called in 2014 — outside of the three lopsided trailers that the documents had been in for over a decade.

"She said she felt bad for him and was angry at him at the same time. Because she could tell he knew he had botched this. Right. So she felt bad for him. But then as an archivist, she was thinking, 'What an idiot! I can’t believe he didn’t call us sooner.' "

"It’s funny in hindsight. If you don’t laugh then you cry," Harvey continued, before pausing and backtracking a bit.

"Out of respect to him," he continued, "he did call us."

From an archivist's perspective, the finding of these documents — of which Harvey and his colleague Mary Zimmeth were able to keep about 10 percent — has been remarkable. Working drawings, the documents serve as blueprints detailing not just the design of the station, but the specifics of how the building was put together.

In recent months, as Ford begins its multiyear process of rehabbing the celebrated building, however, the now saved documents could have increased value. They can serve as a road map for the recovery.

"What makes these different is that they’re the 'as-built' drawings, they’re the shop drawings, if you will, detailing things like the light fixtures or the architectural details," Harvey said, explaining that while presentation drawings already exist at the Burton Historical Collection at the Detroit Public Library, the working drawings are one of kind, detailing everything from the installation of the light fixtures to the construction of the marble facade.

"It actually has the numbering system for how to put the marble back up in the pediment. So it’s super detailed. It’s the order in which the pieces were installed," said Harvey, explaining the significance of the drawings with the current rehab project.

"It’s not just, ‘Hey, we found these old drawings of that old depot, isn’t that swell.’ It’s reading about, the Ford Land Company who are saying, ‘Hey, one of our priorities is restoring the lighting inside the depot that was vandalized.’ And these drawings are the detailed drawings of the lighting fixtures," he said.

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The documents are so important, he said, that his team, a part of Michigan's Department of Natural Resources, reached out to both Ford Land and Quinn Evans, the architectural firm Ford has hired to help with the rehab.

"They expressed interest. They definitely acknowledged that these are documents that are going to make their lives much easier," Harvey, said explaining that the companies are still knee deep in Phase One of the rehab — stabilization. "It’s our hope that they come back and work with us."

How these valuable documents came to end up in a machinist's yard in Trenton is not exactly an easy story.

From an archivist's perspective, there is a lot of frustration — if only they had just called earlier! There also is a clear understanding that those who held onto the records clearly cared.

According to Harvey, the documents were originally removed from the station by employees. He does not know their identity. But sometime around Jan. 5, 1988 — the date the last train rolled out of the depot — thousands of documents were removed from the building.

"These were the things that the railroad company did not transfer and just left there," Harvey said, explaining that the documents were likely abandoned because of their volume and because they were working drawings — the type you don't remove during operation. "You don’t move those. If you’re still operating the building, your facilities staff relies on those."

The documents were originally brought, according to Harvey, to a storage building in metro Detroit.

"It was in a storage facility that was in good condition. This is sort of the tragic part of the story — it was in good storage, the intention was to open up a museum by these private individuals so that people could research the materials," he said.

When the person leading the charge passed away, however, the documents were movedby his widowto a Quanset Hut storage unit. When she passed away, they moved to the possession of the gentleman who eventually called Harvey — a friend of the family who cared about the preservation of the records but also didn't know what to do with them.

"He was saddled with this responsibility because they had no heirs, and fearing that they were just going to get destroyed because they had to get moved out of this other storage facility because of rent payments, he had them moved into the three trailers," Harvey said.

For years, the documents remained in the trailers. But in 2014, the trailers were flagged as a code violation by the City of Trenton. They had to be moved. But after years of just sitting in a muddy backyard, they were, according to Harvey, immobile.

That's when he got the call.

"He gave me no specifics. He just gave me the information, which is probably good. Because if he just said, ‘Hey, there are three raccoon-infested trailers with maybe some stuff in it,’ we may not have done that," said Harvey.

Luckily, they did go to the site. And after a save-and-dump at the location, they brought back thousands of documents — 10 percent of what was in the trailers — to the headquarters of the Archives of Michigan, which is part of the Michigan History Center in Lansing.

"It’s probably how a battlefield surgeon feels. Did you do a good job? Yeah, you did the best you could. It’s heartbreaking to be in that position," Harvey said of the donor explaining that his discovery of the now invaluable drawings was almost by chance.

"Really, the way I found the drawings, in the back of Trailer One, was there was just a big mound of stuff. I climbed up on the mound and took my two hands and dug down into it, and I started to see rolls of drawings," he said, noting that as he looked into the corner of one of the sheets he was somewhat amazed. "After that, we just sort of did an archaeological dig in the back of the trailer to find anything that was a real drawing, and we’re still going through it."

It's been almost four years since the discovery in the trailers and Harvey and his team are still going through the documents. One of the most difficult aspects of the preservation boils down to the condition of the documents.

"They’re really dirty. I mean if I touch them my hands are black," said Leslie Edwards, the lead archivist on the project, explaining that when she started at the department six months ago and was introducedto the project, her eyes "popped" out of her head.

"I kind of sat there and looked at it and thought, ‘Oh my God, where do I even start?’ Because there were these big rolls and pallets. Some were wrapped in plastic and some were just thrown on top. You could just see the dirt. It was a little daunting," Edwards said.

While Quinn Evans requested the documents be digitized, the state-funded department is struggling with the costs. Just bringing a preservation specialist out from Boston to assess what needs to be done would cost an estimated $7,000. Actually preserving and digitizing the documents could cost roughly a couple hundred thousand dollars.

"We’re not digitizing yet, because they’re not in any condition to be digitized yet," said Edwards. "We need to have a conservator come to assess the drawings and what conservation efforts need to happen and make recommendations for a treatment plan."

In December, the organization created a GoFundMe account to try to offset the costs.

While the future of the documents hangs in the balance, there is relief in knowing they are now, at the very least, in a safe, air-controlled, clean location. History has been maintained.

"This is a whole story of what was happening in Detroit at the time," Edwards said of the documents, and how they, in many ways, pay tribute to the hundreds who helped make the magnificent building possible. While the building was designed in the early 1900s by Warren & Wetmore of New York and Reed & Stem of St. Paul, Minnesota, the documents that were preserved point to the true team effort that went into its creation.

"We always talk about the architects. But we forget about the hundreds of other people who helped to build that building. I like that part. I like to illuminate the sort of forgotten people. The craftsmen," Edwards said. "You see these drawings and you think, ‘Oh, my God. These people are amazing. That they made these things.' "

Allie Gross focuses on development, housing affordability, and income inequality. Contact Allie Gross at AEGross@freepress.com. Connect with her on Twitter @Allie_Elisabeth.