HANFORD SITE, Wash. - UPDATE 7:36 p.m.

According to the DOE, the alert and "take cover" orders have been lifted as of 6:39 p.m. and the leak has been isolated and closed off.

No employees were injured and all workers are accounted for.

The leak was initially reported at 4:17 p.m. at a Waste Treatment and Immobilization Plant (WTP) holding tank. Hanford says ammonia is used to reduce nitrogen oxides in the upcoming waste vitrification process.

Said system is not currently in operation. A 100-foot isolation boundary was established around the leak area and more actions will be considered in the morning as it's monitored overnight.

For more information, visit the Hanford Site website.

ORIGINAL COVERAGE 5:44 p.m.

The U.S. Department of Energy activated the Hanford Emergency Operations Center Friday evening following the detection of an ammonia leak within the Hanford Site.

The alert was activated at 5:25 p.m. immediately following the leak's detection at a holding tank near the Waste Treatment Plant.

The DOE notes that an alert is the lowest level of emergency classification. No impacts from the emergency are expected to go past the facility boundary.

Emergency personnel from Hanford are responding to the leak. Workers within the 200 East area of the site are under a shelter-in-place order with directions to close all doors, windows and ventilation.

All other site personnel have been told to stay away from the 200 East area and remain in their work locations.

The 200 East area is located about seven miles from the Columbia River and 22 miles north of Richland.

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