SYSTEM OF SECRECY IS LABELED `ABSURD' Knight-Ridder News Service WASHINGTON - A file designated WCD-9944-X-1 lies under lock and key on the sixth floor of the National Archives. Inside the file, faded and frail with age, is the oldest classified document in the United States. Subject: Troop movements in Europe. Date: April 15, 1917 - nine days after the United States entered World War I. Classification: Confidential. The document stays secret because the US Army says releasing it would damage national security. Archives are opening and secret documents are being released behind the Iron Curtain. Lies are being erased and blank spaces are being filled with official histories. Yet in Washington, millions of documents remain classified for no clear reason, according to historians, researchers and government officials. The secrecy that keeps the seal on file WCD-9944-X-1 "signifies the level of absurdity that he classification system has reached," said Steven Aftergood of the Federation of American Scientists, who discovered the document's existence last month. No one knows how many classified documents there are in the United States. "A mountain...tens of millions, or hundreds of millions or billions," said Steven Garfinkle, whose job as head of the federal Information Security Oversight Office is to track the government's secrecy system. No one knows how to go about reading, declassifying and releasing all of those documents. "We've got to do something, or that mountain's going to build up more," Garfinkle said. "What are we going to do? Wave a magic wand and declassify it? Burn it?" No one knows how much of the hidden record of the nation's history will stay secret forever. File WCD-9944-X-1 is one of "several documents that date back to the World War I era that remain classified," Garfinkle said. "Obviously, it seems absurd on the surface." Michael Knapp, an archivist at the military-reference branch of the National Archives, is one of the few people to have seen the document since 1917. He said he uncovered it in response to Aftergood's Freedom of Information Act request for "the oldest military document that we have that is still classified." Knapp said the document discusses "troop movements in Europe" during the first days of World War I. He said he could not discuss its tittle, its length or its language, because it is classified "confidential." That secrecy classification remained in place after the Army last reviewed the document in December 1976. Under a 1981 presidential order tightening security strictures, a document may be classified "confidential" if its disclosure would damage national security. Since the document remains secret, it's hard to know how the information in it would harm the nation 73 years after Word War I ended.