Eruptions threaten Hawaii power plant
Geothermal site’s underground wells are square in the path of lava flow
Authorities were scrambling to firm up contingency plans Tuesday as lava pouring from Hawaii’s Kilauea volcano slowly encroached on a power plant on the Big Island.
The lava flow entered the 800-acre property of the Puna Geothermal Venture Plant (PGV) 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, flammable gas. Most of the wells have been capped with thick steel plates.
Thomas Travis, an administrator of the Hawaii Emergency Management Agency, has warned that the intense heat could weaken 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.”
The plant has been shut down, and tens of thousands of gallons of flammable gas stored at the site have been removed.
County, state and federal authorities are monitoring the flow and working with the power plant “to ensure the safety of the surrounding communities,” the county civil defense agency said in a statement. It added that nearby residents should be prepared to leave the area with little notice because of gas or lava inundation.
“This situation will be closely monitored,” it said. “There is no immediate threat to any of the wells.”
PGV is a geothermal energy conversion plant that extracts steam and hot liquid from underground wells. The liquid, or brine, is not used for electricity, but the steam is directed to a turbine generator that produces electricity. Even the exhaust steam from the turbine is used to heat fluid to drive a second turbine, generating more power.
The electricity generated by PGV is sold to Hawaii Electric Light.
Authorities also are contending with another threat as molten rock finds its way to the ocean: laze. Laze forms when 2,000-degree lava hits the cooler seawater. A hydrochloric acid steam cloud billows into the air, along with fine particles of glass.
The acid in the plume is about as corrosive as diluted battery acid, scientists said. Laze can cause irritations of the skin, eyes and lungs, and people who have asthma or emphysema may be particularly vulnerable.