Conserving the Stories They Tell

How conservators at the 9/11 Memorial Museum care for the artifacts of trauma.

By Hillary Mohaupt | September 8, 2017
9/11 memorial column

9/11 Memorial Museum Assistant Conservator Maureen Merrigan working on the last column.

9/11 Memorial Museum/photo by Jin S. Lee

ID badges. An elevator motor. A woman’s shoe. Bicycles still locked to a bike rack.

Every artifact in a museum’s collection has a story to tell: that story could be about a decades-long tradition, or it could be about the day everything changed. The National September 11 Memorial & Museum is full of objects that tell the story of one day that changed the course of American history and the lives of countless people, in New York and around the world.

Ensuring that these objects can continue to tell that story is the responsibility of Lisa Conte, the museum’s head of conservation; Maureen Merrigan, the museum’s assistant conservator; and the rest of the conservation team. They don’t work in a vacuum: there are ongoing conversations with the professional conservation community, the museum’s internal curatorial and exhibition teams, and the families who have donated artifacts.

The 9/11 Memorial Museum is the steward of more than 15,000 physical objects, plus tens of thousands of digital assets—which makes the staff members, as Conte says, “pioneers of stewardship of a very specific type of collection.” Their task is unique in part because the collection is composed of modern items made of relatively new materials. Caring for these artifacts and conserving them is exciting but also a little “terrifying,” Conte says, because there is no comparable precedent.

How do you preserve something like duct tape, which was never meant to have a bond that lasts forever? What will happen to the different plastic components in a burn mask? To understand and anticipate how these materials may age, Conte and Merrigan must gather as much information as possible about the components in each object.

The museum staff collects this information from studies like the one conducted by the National Institute of Standards and Technology on the collapses of three World Trade Center buildings, from the objects themselves and the environment around them, and from the artists who create fine-art tributes to victims. They conduct materials analyses, looking closely at objects through a microscope in order to understand what comprises them. They monitor the temperature and relative humidity of exhibition and storage spaces, and they monitor light levels with hand-held light meters. Spikes in any of these environmental readings indicate strain on the objects.

Conte, who has a background in fine-art conservation and is a paper conservation expert, often finds herself asking how things are made and how they work. Merrigan, who was trained in marine archaeology conservation and returned to New York City to assist the museum after Hurricane Sandy flooded the site, aims to understand objects by thinking of them in their constituent parts.

Today, most of the museum’s artifacts are not old enough to require much more than preventive intervention, but these insights help the conservators plan for future decision makers, including their successors, curators, and other museum staff.

A key decision conservators make early on in any project is which moment in the object’s story they want to preserve. This determines the baseline from which conservators can evaluate future changes and identify areas of concern for each object. At the 9/11 Memorial Museum that critical moment in some instances is “the moment of recovery,” or “immediately after the collapse of the towers,” Merrigan says.

Choosing to focus on the aftermath of the collapse means the trauma of 9/11 is apparent in each artifact. The elevator motor will never again function the way its manufacturers intended; the fire truck will never speed down another crowded street. Instead, these objects and others like them now have another job: to tell the story of one day in September 2001.

Paper ephemera exhibit tears and burns that must be stabilized. The steel-beam cross from Ground Zero still bears the written evidence of first responders. Though the readability of the writing has diminished, it will not be as vulnerable to damage as when it was outside on “the pile,” because the cross now lives in a stable environment.

Some of the objects already demonstrate the “inherent vice” of modern materials, like the burn mask made of several different plastics and adhesives degrading at different speeds. The differences in materials relatively unknown to museum staff will require thoughtful decision making, and the conservators have suggested that some documentation (like photos, video, and other notes) become part of the object’s story even as the object’s materials continue to change.

Ordinarily, conservators in museums restore an object to its original function, putting it in the context of its original use and value. But for most of the objects in the care of the 9/11 Memorial Museum, the value of the object has changed and so has its use. Take, for example, the elevator motor currently on view, which was damaged in the collapse of the World Trade Center towers, its warped appendages and mangled wires a testament to the destruction of the day. “So we didn’t remove . . . the signs of damage and trauma,” says Conte. As with some other objects, the museum “may allow it to continue to decay because it’s part of the story it has to tell.”

Likewise, the fire truck from Ladder Company 3, which sits nearby, was “never going to be whole again,” Merrigan says. The doors were removed during recovery and were later returned during exhibition planning, but the museum team elected not to reattach them—it comes back to that crucial baseline moment—so now the doors are shown next to the truck, in the same display.

The conservators have not actively intervened to preserve the truck, except to evaluate its materials and their integrity. The placement of the mounts minimizes the force exerted on the tires, reflecting the fact that the rubber in the tires will continue to age and will eventually be the first part of the truck to break down.

Many of the items at the 9/11 Memorial Museum spent time at Hangar 17 at JFK Airport, which served as storage and as a critical space for conservation assessment between removal and museum construction. Now the museum’s conservators aspire to monitor their collection at the object level.

Lady Liberty, for example, is a memorial composed of many different materials, including both natural and fake flowers, as well as construction paper that was readily available to mourners. The memorial stood outside for an extended period and endured the impact of the elements. Parts of the memorial are now oxidizing, and there is photolytic damage on the construction paper. Mostly, conservation for this object is about stabilization.

In the dim quiet at the end of the Historical Exhibition sits a bike rack with six bicycles chained to it. The bikes are twisted, and the lighting above their platform suggests they are still blanketed with the dust of the day the buildings fell. Authorities once hoped the bike owners would return to Ground Zero to claim them. But now the rack and the bikes reflect a moment in time, when a regular morning was no longer normal. The bikes were cleaned and transferred to Hangar 17 at JFK, where conservators intervened to stabilize the damage. Conservators will have to make future decisions beginning, as with the fire truck, with the disintegrating tires.

When visitors arrive at the 9/11 Memorial Museum, they make their way down to the bedrock level, into the bowels of what was once the site of the World Trade Center. They follow a ramp reminiscent of the one used to ferry out the debris, and they pause at the slurry wall that once held back the Hudson River. Below this overlook stands the Last Column.

The Last Column is made of steel and concrete; it’s covered with rust, mill scale, paint, photographs, and the handwriting of the grieving. The last item removed from Ground Zero in May 2002, the 58-ton box beam from the South Tower became a spontaneous memorial for the recovery workers and first responders. It stood outside for nine months before being transferred to the JFK hangar, where the initial conservation treatment was completed. Later, the beam was one of the first artifacts moved into the new museum and was permanently installed in the museum’s Foundation Hall in August 2009, which means it can no longer be rotated or removed from view to protect it over time.

To the average visitor, the Last Column appears to be one solitary, evocative object, but to the museum staff it is actually made up of one base column and nearly 150 pieces of ephemera. Merrigan says that the conservation process respects the fact that this was a spontaneous memorial: people used materials on hand, slipping photos printed on ink-jet printers into plastic sandwich bags for makeshift lamination, and duct-taped these mementos to the column.

The Last Column alone, fixed in the bedrock floor forever, is breathtaking; the hours of painstaking work involved in its conservation is another thing entirely. To care for this complex object, conservators embarked on a complicated intervention beginning with consolidation. Instead of cleaning off the rust and mill scale, which was the product of exposure but also the surface on which people had affixed images and painted other remembrances, conservators injected polyvinyl butyral resin into the column’s substrate to keep the surface from cleaving from the steel. They also sought to preserve the legibility of the images taped to the column in makeshift plastic bags. Some of the images are faded—because of the limitations of early-21st-century ink technology as well as a period of exposure to the elements at Ground Zero. Other images are no longer originals (which remain in collection storage) but facsimiles that allow the museum, as Conte says, to “preserve the original state in which [the column] came into the collection.” This keeps the light-sensitive original material from deteriorating further.

Each item has to remain legible and to tell its story. Between the affixed images and the column, there is now a buffer layer to mitigate potential damage caused by the interaction between the materials, which also allows the conservators to monitor each ephemeral piece. Because the adhesives may eventually degrade, each piece is attached to the column with magnets so they can easily be removed for examination or treatment.  This process also allowed the museum to document each of the ephemeral pieces and the column—to record the condition and stories of each piece.

Conte and Merrigan say that technology is on its way to catching up with the future needs of the museum’s modern collection and the requirements of preserving each artifact’s story. Some museums are exploring 3D printing as a conservation tool; other museums may deploy exhibit copies—like the facsimiles on the Last Column—as a means of preservation.

Faced with the unknown, it becomes even more important to collect as much information as possible. So conservators record not only the decisions made about preservation and conservation today but also the thought process behind them. Humans change over time, too, “so that information is part of your toolbox,” Conte says. “You do the best you can with the information you have at the time. Approaches will evolve, just as we all evolve.”