By Gabriel Debenedetti
WASHINGTON (Reuters) - At an undisclosed location 10 miles from Washington, Senate employees in protective garb go envelope by envelope through millions of letters destined for the Capitol to thwart mail-borne bioterrorism threats like the recent ricin scare.
With suspect James Everett Dutschke facing a hearing Thursday on charges of attempting to use the poison as a weapon, the laborious, largely secret process used to screen mail to Washington officials is getting attention.
Authorities say the procedures used to inspect mail for the Senate, the House of Representatives and the White House have thwarted hundreds of potential threats. The ricin letters were intercepted before reaching their intended recipients, President Barack Obama and Senator Roger Wicker of Mississippi.
Each letter passing through the Senate's Landover, Maryland, facility is "slit open, shaken or turned" before being screened for suspicious substances, said Senate Sergeant at Arms Terrance Gainer, whose office supervises the inspections.
The whole process takes at least 48 hours per letter.
Gainer said that of 18 million pieces of mail screened in 2011, about 400 suspicious letters and packages addressed to Senate officers were intercepted. At that point, Capitol Police is notified for further analysis.
However, most suspicious mail discovered on Capitol Hill has arrived outside the normal delivery process, such as any piece hand-carried into the building, Gainer said.
Capitol Police on Monday sent a hazmat team to the office of U.S. Representative Gregory Meeks after an aide to the New York congressman discovered powder in a letter. The powder was cleared as not dangerous, and Meeks' staff returned to work after a few hours.
Screening procedures used at the House of Representatives are so closely guarded that a spokesman for House Chief Administrative Officer Daniel Strodel declined to comment.
Gainer, who said the House process resembles the one used by the Senate, would not disclose the location of the Senate's off-site facility. But it was identified in a Senate resolution sponsored by Wicker, praising workers who discovered the ricin.
A few details also emerge during congressional hearings, when officials seek additional funds.
Strodel said in a recent hearing that his office intends to help members see the contents of constituent letters faster by scanning letters and sending them electronically while the physical inspections occur.
The Secret Service screens more than 1 million pieces of White House mail each year at its facility in Washington that opened in 2010, said the Secret Service's Edwin Donovan.
Congress approved construction of a new center as fears mounted about bioterrorism aimed at the White House. Then-Secret Service Director Mark Sullivan asked a House subcommittee for $2.9 million for equipment at the screening center in 2010.
Gainer's office said it spent $329,000 in fiscal year 2012 on the screening process. Once a letter is slit open and shaken, Gainer said, "it sits for 24 hours while various air samples are taken. If they're clear, it goes to the next process, where individuals who are properly suited in protective gear open each one of the letters in a protected hooded environment."
The mail sits for yet another 24 hours for another round of air samples, then it is delivered to the Capitol.
(Editing by Marilyn W. Thompson and Doina Chiacu)