Senate offices get final anthrax cleaning

WASHINGTON -- Workers wearing protective suits and air tanks pumped poisonous gas into a Senate building contaminated with anthrax in a cleanup Saturday intended to make it possible to reopen shuttered offices.

"We've taken great pains to have a plan that we think is effective," said Lt. Dan Nichols, a Capitol Police spokesman.

The fumigation with chlorine dioxide gas was delayed for seven hours because of complications in reaching the high humidity level needed to most effectively kill the remaining anthrax spores in the Hart Senate Office Building.

Technicians for the Environmental Protection Agency, which is in charge of the first anthrax decontamination in the United States using the gas, began pumping the gas into the building at 2 a.m. Saturday.

Richard Rupert, the EPA's on-site coordinator, said the fumigation might extend a bit beyond the planned 12 hours in order to "get an extra measure of confidence."

The initial hitch required rerouting steam from the building's heating system to raise the humidity. It also took workers longer than expected to put up testing strips to check later if the fumigation was successful.

"Everything's rolling along and it's running remarkably smoothly," Rupert said as crews monitored for any leaks of the gas from the building. "There's been nothing detected outside."

The gas is mixed in a vessel outside the building, then routed through chemically resistant plastic pipes into Senate Majority Leader Tom Daschle's office suite, which was been sealed off with duct tape, plastic sheets and plywood with foam.

Breaking down gas

The next phase in the operation, to start later Saturday, involved inserting the chemical sodium bisulfite into the offices to break down the gas. That was expected to last about six hours, Rupert said.

The intent was to kill anthrax bacteria that escaped Oct. 15 when an aide to Daschle, D-S.D., opened an anthrax-tainted letter.

The rest of the office building was not similarly sealed, although the adjacent Dirksen Senate Office Building, connected by hallways with Hart, and the Hart underground garage were closed as a precaution. Half the Senate's 100 members have offices in Hart.

Some liquid chlorine dioxide was used in Daschle's suite beforehand. Rugs and some artwork were left in place to be gassed. Other senators' suites in the Hart building also need to be cleaned up, although officials so far do not believe the gas will be necessary in those areas.

Cleanups using liquid or foam decontaminants have begun in some of 13 other senators' offices where traces of anthrax were found.

Streets blocked off

Around the building, police blocked off streets. One of the EPA's $1 million laboratory buses circled the building every 15 minutes to monitor the air for gas leaks.

Dr. Jeffrey Koplan, director of the federal Centers for Disease Control and Prevention in Atlanta, said before the operation that it was unlikely that workers could remove every anthrax spore.

"There's no intention to open the building until everyone feels very comfortable that people working in there or visiting in there will be safe," he said. "This is new territory for both the EPA and certainly for us. We haven't had this experience before as a country in how do you clean up a building like this."