Denver — "Broken arrow" is the Pentagon's code word for a serious accident involving a nuclear weapon. Although not a hazard most people think about, it is something the Department of Defense now takes extremely seriously. Evidence of this is the $2.2 million exercise called NUWAX-81 conducted last week in the Nevada desert 100 miles northwest of Las Vegas.
In order to test the government's response to this type of accident, military officers and federal officials staged a hypothical "crash" between a private aircraft and an Army helicopter carrying three (make-believe) nuclear bombs. The accident was contrived near a mock-up of a rural town, called Wahmonie, Calif., in the middle of the 1,300-square-mile Nevada Test Site.
Since 1950 the Pentagon has acknowledged 32 "broken arrows." The most recent was the explosion of a Titan intercontinental ballistic missile in its silo near Damascus, Ark., last September. The nuclear warhead was blown clear by the blast. Although the warhead was damaged, its conventional high explosive charge did not detonate and no radioactive material was released, according to the Pentagon.
The Damascus incident was the first "broken arrow" in 12 years. From 1950 to 1968, however, serious accidents involving nuclear weapons were averaging almost two a year. This included the notorious disaster at Polomares, Spain, in 1966 --while refueling. As a result, an intact hydrogen bomb parachuted into the ocean and two bombs ruptured, contaminating a large area of Spanish countryside.
The number of nuclear weapons shipped around the country and overseas is classified, but appears to be fairly high.
"We wouldn't be conducting this exercise if we didn't think this could happen ," says David Jackson of the Department of Energy (DOE), which supplies technical assistance to the military in these cases.
The current drill is the second of its type. The first, NUWAX-79, took place two years ago. It simulated an accident in an unpopulated area.
A future test is planned that will probably simulate an accident in a more densely populated area, says David Cobb of the Federal Emergency Management Agency (FEMA) which is participating in this year's test.
"NUWAX is like a fire drill on a ship. You assume everything goes wrong at once. Then, if you can handle this incredible situation, you should be able to handle a credible one," Mr. Jackson explains.
To make the situation as bad as possible, they put three nuclear bombs on one helicopter. They assumed that the high explosive in one bomb exploded, a second ruptured, and the third retained its integrity and was thrown clear. They also scripted it so that four of Wahmonie's 40 imagined citizens were killed in the explosion following the crash.
In a situation like this, forces from the nearest military base move in as quickly as possible and cordon off the area. The local commander declares the site a National Defense Area, an action that puts the land around the site under federal jurisdiction during the emergency.
Next, specially trained personnel from the military branch which owns the nuclear weapons involved fly in and take charge. For the current test, this was the US Army. Also, technical experts from DOE, FEMA, the Environmental Protection Agency, and the National Oceanic and Atmospheric Administration arrive on the scene to monitor radiation levels, treat the injured and exposed, keep track of the weather, and perform other needed functions. Some 1,100 people were involved in the test.
For added realism, the radioactivity of the plutonium debris was mimicked by trace amounts of radioactive radium and mercury. Actually, plutonium is only mildly radioactive. How ever, it is highly flammable and extremely poisonous.