The pentane at Puna Geothermal Venture has been removed, but Civil Defense officials remain concerned about another hidden hazard.
Talmadge Magno, county Civil Defense administrator, said state and county officials are talking with well experts in California about how to seal the power plant’s geothermal wells to prevent the release of hydrogen sulfide if well caps are compromised by the ongoing lower Puna volcanic eruption.
“We’re looking at basically filling the wells with water,” he said, to prevent an unabated gas release.
But, to accomplish that, equipment needs to be flown from the mainland. Magno said that could take days, but not weeks.
“I don’t know how much time we have so we’re acting on it,” he said.
PGV, a 38-megawatt geothermal power plant, is located in Pohoiki on Kilauea’s East Rift Zone near Leilani Estates and Lanipuna Gardens, the site of the eruption. Its wells are between 6,000 and 8,000 feet deep.
Jim Kauahikaua, a geophysicist with the Hawaiian Volcano Observatory, said ground cracks have been observed at PGV since the eruption started.
In response to community concerns, Gov. David Ige issued an emergency declaration for the immediate removal of pentane, a highly volatile material, at the plant. The 60,000 gallons of pentane was relocated to Shipman Business Park in Keaau.
Asked if hydrogen sulfide could be released from wells if the plant is inundated with lava, Mike Kaleikini, senior director of Hawaiian affairs for PGV, said, “That’s one scenario in our emergency response plan.” But he wouldn’t say if or how it could be contained. A hydrogen sulfide release would compound health hazards for residents potentially beyond the evacuation area, depending on wind direction.
PGV has shut down operations since the eruption started May 3. It had moved pentane to higher ground before relocating the chemicals. Before the declaration was issued, Kaleikini said Monday that PGV was trying to remove the pentane in a matter of weeks.
It’s unclear how much hydrogen sulfide could potentially be released or how long a release would occur.
Email Tom Callis at tcallis@hawaiitribune-herald.com.