Authorities in Hawaii were scrambling to firm up contingency plans Tuesday as hot, powerful lava flowing from Hawaii's erupting Kilauea volcano slowly encroached on a Big Island power plant.

The lava flow entered the 800-acre property of the Puna Geothermal Venture Plant on Monday and had stalled at a swale about 300 yards from the nearest underground well. On Tuesday, the lava was advancing.

"Fissure 6 reactivated last night and has been erupting since around midnight," Hawaii County civil defense officials said in a statement. "The flows from Fissure 6 are slowly flowing closer to PGV property."

If lava breaches wells, authorities fear it could release hydrogen sulfide, a toxic and flammable gas. Most of the wells have been capped with a thick, steel plate.

Thomas Travis, an administrator of the Hawaii Emergency Management Agency, has warned that the intense heat could diminish the strength of the metal.

“That’s why having lava flow across the well causes some uncertainties that have to be dealt with," he said. "To our knowledge, no one has faced this before."

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https://www.usatoday.com/story/news/nation/2018/05/22/hawaii-volcano-lava-kilauea-power-plant/632294002/