Staff Sgt. Kevin Rivera, Air Force Radiation Assessment Team, checks a servicemember's radiation levels in Fukushima Prefecture on March 29, 2011. The U.S. military collected radiation and toxin samples at hundreds of places throughout Japan after the March 11 earthquake and tsunami knocked the Fukushima Dai-ichi nuclear plant off line.

A U.S. federal judge has ruled that a class-action lawsuit filed by about 200 Navy sailors and Marines can proceed against Japanese utility TEPCO and other defendants who they blame for a variety of ailments from radiation exposure following a nuclear reactor meltdown 3½ years ago.

In a decision released Tuesday, Southern District of California Judge Janis Sammartino ruled that the suit can be amended to add the builders of the Fukushima Dai-ichi Nuclear Power Plant reactors — General Electric, EBASCO, Toshiba and Hitachi — as defendants.

Sammartino also denied a change of venue to Japan and dismissed several minor aspects of the suit. The plaintiffs’ lawyers have until Nov. 18 to make changes to their filings.

“It is not over, but we have won the major battle,” lawyer Charles Bonner wrote in an email to his clients that was provided to Stars and Stripes.

“THANK GOD!!!!!” responded Lindsay Cooper, the first USS Ronald Reagan sailor to come forward and report an illness.

Sammartino’s ruling was a bit of a surprise. The Defense Department, including Assistant Secretary of Defense for Health Affairs Dr. Jonathan Woodson, have concluded that the illnesses are not a result of the servicemembers’ work in Operation Tomodachi, in which a massive earthquake on March 11, 2011, spawned a tsunami that swamped the nuclear plant.

The suit was first filed in 2012 by a small group of sailors off the USS Ronald Reagan, who alleged that TEPCO’s misinformation coaxed U.S. forces closer to the affected areas and made them sick. More ailing servicemembers came forward citing exposure-related ailments such as unexplained cancers, excessive bleeding and thyroid issues.

The suit has been refiled a number of times, adding plaintiffs and, more recently, additional defendants.

TEPCO tried to have the case dismissed. Oral arguments were presented Aug. 25.

Bonner and fellow attorney for the sailors, Paul Garner, said additional plaintiffs are continuing to come forward with “serious ailments from radiation,” according to a statement released by the legal team.

burke.matt@stripes.com