Now you see it, now you don’t. That’s the problem with the Internet, it’s so impermanent. One day a website exists and the next day it’s gone. For reporters doing research online, this can be infuriating.

When PITTSBURGH TRIBUNE-REVIEW reporter Carl Prine was researching emergency preparedness plans at sites containing large amounts of hazardous chemicals, he kept hitting the same wall. After 9/11, reports that were once accessible online to the public were suddenly erased from cyberspace. Almost. Using an Internet archive site called the Wayback Machine — the investigative reporter’s virtual time machine — he was able to retrieve several reports from the EPA and other agencies that were no longer available on the sites at which they were originally posted.

Internet archives like the Wayback Machine take “cyber-snapshots” of websites periodically and store the data in a virtual library.

When Prine was researching the potential impact a chemical spill could have on surrounding neighborhoods, he went to a site called, which stores information about chemical companies and environmental pollution. He knew of a map that showed vulnerable zones near DuPont facilities in several states. But when he went to the map’s URL in 2002, it was gone. Check it out: … Nothing, right?

Then Prine searched the same URL in the Wayback Machine and selected a screenshot from before 9/11. Problem solved. See for yourself:

Prine also used the Wayback Machine to fish out a CDC report on possible chemical vulnerabilities and EPA “worst case scenario” data that showed people living near chemical plants how they might be harmed in the event of an unintentional release.

“It should be noted that all these documents were denied to me by FOIA, but accessed on the computer,” Prine wrote in a follow-up e-mail to the Blog. “Ghosts in the machine, they live on.”

“While these documents are denied by FOIA officers today, they obviously are freely available to terrorists who are savvy enough to know what the Wayback Machine is,” Prine points out. “Which leads me to ask why the information was taken away? Is it to deny to terrorists essential targeting information? Or is it to deny to Americans the realization of these vulnerabilities? Perhaps both. Perhaps neither. We’ll never know.”

Carrie Ching

Carrie Ching is an award-winning, independent multimedia journalist and producer based in the San Francisco Bay Area. For six years, she led digital storytelling projects at the Center for Investigative Reporting as senior multimedia producer. Her multimedia reports have been featured by, The Huffington Post, Rolling Stone, Grist,, Fast Company, the Los Angeles Times, The Washington Post, KQED, PBS NewsHour,, Mother Jones, Public Radio International, Poynter, Columbia Journalism Review and many other publications. Her specialty is crafting digital narratives and exploring ways to use video, audio, photography, animation and interactive graphics to push the boundaries of storytelling on the Web, tablets and mobile. Her work has been honored with awards from the Society of Professional Journalists, Investigative Reporters and Editors, Best of the West, the Online News Association, Scripps Howard, The Gracies, and was part of the entry in a Pulitzer-finalist project. Prior to her time at CIR she was a magazine and book editor, video journalist, newspaper reporter and TV comedy scriptwriter. She was on the 2010 Eddie Adams Workshop faculty as a multimedia producer working with MediaStorm to teach digital storytelling techniques to photojournalists. She completed a master’s degree in journalism at UC Berkeley in 2005.