Hundreds of residents on Hawaii’s Big Island are living in peril as fissures on the Kilauea volcano continue to erupt with lava.

Lava has destroyed about 35 structures and has burned land equivalent to more than 75 football fields.

Although Kilauea has been burning for two weeks, scientists have yet to determine when eruptions will come to an end – it could be days, months, or even years. Scientists are studying earthquakes and the makeup of gas coming out of cracks in the ground to determine if the eruption will strengthen.

Bill Chadwick, a volcanologist at the National Oceanic and Atmospheric Administration, said, “We can’t really peer through the ground and see it exactly in all its details and intricacies. It could last days, weeks, years. All that’s possible. It’s hard to say, unfortunately.”

According to Hawaii’s civil defense, there are at least 12 fissures around Leilani Estates, a luxuriant residential area, where at least 1,700 people were forced to evacuate. The most recent fissure, the 17th one, formed Sunday in the southeast corner of the Big Island, west of state Highway 132. Residents along Halekamahina Road were forced to evacuate their homes.

As to why lava tears the ground, Denison University volcanologist Erik Klemetti said, “It’s like a leaky pipe or a burst pipe, where the magma is moving down the conduit system and it just reaches a point where the pressure builds enough that you start cracking the surface above.”

Because there is such ambivalence surrounding the fate of the eruption, the future for residents of Leilani Estates could be in jeopardy. “When a house today might look like it’s perfectly safe, it might get taken out by a lava flow five years from now if the eruption keeps on going,” Klemetti said.

On Friday, President Trump declared the Big Island a disaster area, which will allow federal financial assistance for state and local governments to repair damaged infrastructure.

The island of Hawaii has a population of about 190,000 200 miles southeast of Oahu, the most-populous island of Honolulu, the state capital. The eruption has not affected Oahu.