The Northern Marianas Emergency Management Office is assessing whether to lift a disaster emergency regulation on Anatahan island.
The regulation has been in place for the past six years after the Anatahan volcano erupted, but it expired last week.
It bans human habitation and travels to the once inhabited 31 square kilometres island except for scientific expeditions.
The office's seismic technician, Juan Camacho, says it has asked for a 30-day extension of the emergency regulation to decide if it's needed in the future.
"The volcano appears to have entered a quiet period. But it's still possible for more active activity that's including gas or ash emissions. We're doing a close observation of the volcano. If it's still the same, we might lift the declaration of emergency."