A note on a map of the Marshall Islands yesterday should have made it clear that the former U.S. trust territory became independent in 1986. (Published 2/25/94)

After nuclear tests over the Marshall Islands in 1954, U.S. analysts concluded that the radiation fallout was limited. Only 287 persons and three key islands faced significant risk, federal officials said in the initial study. Although widely disputed, the assessment has prevailed over the years.

In fact, the post-explosion cloud of radioactive materials spread hundreds of miles beyond the limited area earlier described in the vast range of Pacific islands, according to federal documents recently discovered by congressional and academic researchers.

The fallout also probably exposed thousands of Marshallese and some U.S. troops to radiation, the documents suggest. The doses apparently were heavy in some cases. A new medical study shows that high rates of radiation-linked thyroid cancer are occurring in residents of the island of Ebeye, far outside of the region of radiation danger initially pinpointed.

The documents, culled from federal archives, reopen one of the darkest chapters of U.S. Cold War history. Beginning with the Bikini test in 1946, the United States held 66 nuclear tests in the Marshall region in the 1940s and 1950s. In an attempt to keep abreast of Soviet hydrogen bomb advances, they staged the biggest series of tests in a six-week period, starting with the Bravo test on March 1, 1954. The Marshall Islands were pounded with six bombs that some critics say had the combined force of 3,000 times what was dropped on Hiroshima.

Yet, U.S. officials decided that there would be only limited precautionary steps to protect U.S. personnel and none to shield the Marshellese, who numbered about 20,000 at the time.

Rep. George Miller (D-Calif.), chairman of the House Natural Resources Committee, has called a special hearing today to review the newly uncovered material and make appropriate recommendations.

"We have clearly done a great deal of damage to the Marshall Islands and the people who live there," Miller said in an interview. "The U.S. government owes those people first of all full disclosure of what happened and what the fallout was. We have never given them that. But we also owe them compensation for their suffering."

The documents were taken from files at the Energy Department and its forerunner, the Atomic Energy Commission, and released by committee staff to help publicize the hearings. They make several new revelations:

* While publicized reports suggested that the only inhabited islands seriously affected by the fallout were Rongelap, Rongerik Utirik and Ailuk, all in the northern part of the islands chain, unpublicized follow-up studies showed that distant islands and atolls also had received significant doses.

A 1973 DOE report said that fallout from Bravo, the first and biggest explosion, possibly affected 13 atolls, including Ailaninae, Kwajalein, Wotho and Wotje. Subsequent explosions may have hit some of the same areas, the report said. A subsequent Defense Department report, released in 1982, made similar conclusions.

"While we have focused so far on the effect of the Bravo test," said David Weiman, an environmental lobbyist who is to testify at today's hearing, "we should be measuring the accumulated effect of radiation from all of the tests, including fallout in things like rainwater, that the locals drank."

Weiman, who studied many of the files, feels they clearly indicated that the heavy radioactive cloud drifted over some of the southern atolls.

* A three-year study by Thomas Hamilton for the Marshallese government in the mid-1980s showed that there was fallout in far southern atolls. Hamilton also concluded that the control group used to monitor radiation on other islands was on islands that also had been irradiated and thus probably was invalidated. DOE officials discounted Hamilton's study.

* U.S. military personnel, who have never been briefed about the tests, were stationed on some of the atolls.

In addition to the documents, Japanese and English doctors commissioned by the Marshallese government recently released a study showing that residents of the atoll of Ebeye are experiencing thyroid cancer at 100 times the level expected in a typical population. Researchers examined 1,368 residents of the atoll, and Peter Oliver, a senior Marshallese official, reported the results to Miller last September.

Beyond the material suggesting a wider radiation fallout, the congressional panel will examine reports that U.S. officials knew before the tests were conducted that the explosions could irradiate populated islands.

Until now, official follow-up reports of the tests suggest that the radioactive debris was supposed to go north to northeast, where there are no atolls. However, an official weather report before the Bravo test indicates that the winds probably would send debris in a southern direction.

Although there were some attempts to move U.S. military personnel, there were evacuations of Marshallese only after the tests.

"We have deliberately kept that information from the Marshallese," Miller said. "That clearly constitutes a coverup."

"One of the biggest crimes here is that the government seemed to clearly know the extent of the fallout coming, but made no attempt to protect people from it," said Jonathan Weisgall. A Washington-based attorney, Weisgall represents Bikini island and is soon publishing "Operation CrossRoads," a book about the 1946 tests held on the island.