Two U.S. Fish and Wildlife Service employees requested to be evacuated from Kasatochi Island in the Aleutian Chain after seismic activity in the area, according to the U.S. Coast Guard.

The island, about 50 miles east of Adak, was reportedly experiencing tremors and volcanic uncertainty, which prompted the Alaska Volcano Observatory to issue an advisory in the area.

The Coast Guard was poised to deploy a helicopter out of Adak late Wednesday and was expecting to pick the workers up at about 10:30 p.m., said Petty Officer 1st Class Jeremy Dawkins. Officials got the call at about 7:40 p.m., he said.

The Alaska Volcano Observatory also issued a yellow aviation color code in the area as a result of the volcanic activity.

According to the observatory, Kasatochi is a stratocone volcano that forms a small island between Adak and Atka islands. Its summit was destroyed during an explosive eruption likely within the past several hundred years that exposed its interior.

Fish and Wildlife personnel stationed on the island have observed evidence of degassing through a lake near its top -- testimony of the volcano's youth, according to the observatory.