US Nuclear Emergency Response Marines Being Sent to Japan

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The ongoing nuclear crisis in Japan has prompted the U.S. military to send a marine unit specializing in nuclear emergency response to be on hand if needed, ABC News has learned.

Trained in personnel decontamination and monitoring of radiation levels, the team would not be involved in the efforts to stabilize the reactors at the troubled Fukushima Daiichi nuclear plant.

Approximately 155 Marines from the Marines' Chemical Biological Incident Response Force (CBIRF) received their deployment orders for Japan earlier today and are scheduled to arrive on Friday.

The team is being sent as what a Defense Department official calls "an initial response force" because they are only a portion of the much larger CBIRF unit.

Based at the Indian Head Naval Surface Warfare Center in Maryland, CBIRF is a Marine unit specially trained to counter the effects of a chemical, biological, radiological, nuclear or high-yield explosive (CBRNE) incident. Usually, that entails being available to assist local, state and federal agencies with domestic emergency responses to CBRNE incidents.

The unit's deployment to Japan "will provide the U.S. on-scene commander a rapid response capability and, if requested, [allow the commander to] assist Japanese authorities by providing advice and expertise in the areas of agent detection and identification, casualty search, rescue, personnel decontamination and emergency medical care," a defense official said.

The deployment of the initial response force is not of an emergency nature, but more as a precautionary move in case they are needed, another defense official said.

The U.S. military has barred its personnel in Japan from entering a 50-mile radius of the Fukushima Daiichi nuclear plant, though exceptions are made for certain relief missions.

The new Marine unit will not be allowed within that 50-mile exclusion area and, if needed, will provide personnel decontamination and monitoring support from Yokota Air Base outside of Tokyo, a defense official said.

The unit's deployment was telegraphed on March 17 when U.S. Pacific Command's Adm. Robert Willard told Pentagon reporters that he sent a military assessment team to Japan to look at the situation around the Fukushima Daiichi plant and determine whether a larger force might be needed.

At the time, Willard said he had "requested a force of about 450 radiological and consequence-management experts to be available to us" on a prepare-to-deploy order and that the assessment team would determine whether they needed to be sent to Japan.

The deployment of the 155 Marines was requested by U.S. Pacific Command and the newly-established Joint Support Force that oversees the overall U.S. military quake and tsunami relief effort in Japan. Adm. Patrick Walsh, who heads the U.S. Pacific Fleet, was named just this week to head the Joint Support Force.