The Bush administration conducted a flawed study of radioactive contamination at a former nuclear testing site near Los Angeles and adopted a cleanup standard that would expose future residents to elevated risks of cancer, a federal judge ruled Wednesday.

US District Judge Samuel Conti ordered the Department of Energy to conduct a full environmental review of plans to remove hazardous substances from the Santa Susana Field Laboratory in Simi Valley, a Ventura County site that overlooks the northwest San Fernando Valley. It was used for federally funded nuclear and other energy research from the mid-1950s until 1996 and was the site of at least nine nuclear accidents, including a partial reactor meltdown in 1959, Conti said.

The Department of Energy has begun cleanup work based on a study that relied on a contamination survey by the Boeing Corp.'s Rocketdyne division, which owns the land. After the cleanup, the company will be free to use the land for residential development or any other purpose.

The study and the department's conclusion - that the cleanup and its aftermath would have no significant environmental impact - have been criticized by the U.S. Environmental Protection Agency, the state of California, Sens. Dianne Feinstein and Barbara Boxer, and the plaintiffs in the 2004 lawsuit, two environmental groups and the city of Los Angeles.

Conti joined the critics Wednesday. Among other things, he said, the department overlooked groundwater contamination, disregarded the combined effects of chemical and radioactive contamination, and set a radiation standard that would give each exposed person a 3-in-10,000 chance of getting cancer, far above EPA safety levels.

The standard "improperly placed future residents of the site at an increased cancer risk many times higher than CERCLA (the federal toxic cleanup law) allows,'' Conti said.

He noted that the contaminated land is only miles away from one of the world's largest population centers, and that federal law is supposed to assure public awareness of the potential environmental effects of government actions.

"It is difficult to imagine a situation where the need for such an assurance could be greater,'' Conti said. Finding that the department committed a "clear error in judgment'' by deciding against a full environmental review, he prohibited transfer of the leased land to Boeing until a complete review is conducted.

Attempts to reach the Department of Energy for comment were unsuccessful.

Feinstein, who has been pressing for stringent cleanup standards for the site for many years, said in a statement that the ruling was "an indictment of the Department of Energy's cleanup plan'' and was good news for nearby residents and the environment.

Dan Hirsch, president of the Committee to Bridge the Gap, one of the plaintiff organizations, called the ruling "a significant blow against efforts by the Department of Energy to walk away from contamination at a nuclear meltdown site.''

Hirsch said the federal government promised during the 1990s to clean up the site according to the safety standards set by the toxics law. But he said the Bush administration withdrew that promise and has embarked on a cleanup that would remove just over 1 percent of the contaminated soil.

The ruling guarantees that the cleanup will not be completed by the time President Bush leaves office, enabling the next administration to take a fresh look, Hirsch said.

E-mail Bob Egelko at begelko@sfchronicle.com

Follow this link to the actual lawsuit in PDF form: http://a4nr.org/library/failures/2007.05.02-santasusanalawsuit/view

http://sfgate.com/cgi-bin/article.cgi?f=/c/a/2007/05/02/MNGH6PJSE56.DTL