One of former Vice President Al Gore's three daughters is among those whose Social Security numbers were on the drive. Other information includes logs of events, social gatherings and political records.
The FBI is conducting a criminal investigation of the matter, according to Rep. Edolphus Towns, D-N.Y., chairman of the House Oversight and Government Reform Committee, and senior committee Republican Darrell Issa of California.
The lawmakers said they learned of the loss from the inspector general of the National Archives and Records Administration. The drive is missing from the Archives facility in College Park, Md., a Washington suburb. The drive was lost between October 2008 and March 2009 and contained 1 terabyte of data - enough material to fill millions of books.
Towns said he would have the FBI and inspector general brief committee members so they can "begin to understand the magnitude of the security breach and all of the steps being taken to recover the lost information.
"The committee will do everything possible to prevent compromising the integrity of the FBI's criminal investigation while we fulfill our constitutional duty to investigate the compromised security protocols," he said.
Issa called for the Archives acting director, Adrienne Thomas, to appear before a committee panel Thursday to "explain how such an outrageous breach of security happened."
"This egregious breach raises significant questions regarding the effectiveness of the security protocols that are in place at the National Archives and Records Administration," he said.
Issa said the hard drive was moved from a "secure" storage area to a workspace while it was in use. The inspector general explained that at least 100 badge-holders had access to the area where the hard drive was left unsecured.
Besides those with official access to sensitive material, the inspector general said janitors, visitors, interns and others passed through the area, according to Issa. Further, the workspace is in an area that Archives workers pass through on their way to the bathroom and the door often is left open for ventilation.
"The IG is investigating the situation as a crime with the assistance of the Department of Justice and the Secret Service but they have not yet determined if the loss was the result of theft or accidental loss," Issa said.