While Tropical Storm Iselle apparently didn’t cause any serious injuries, some lower Puna residents think the same cannot be said for the steam release that occurred at Puna Geothermal Venture while they were hunkering down for Iselle’s arrival.
The release, which included hydrogen sulfide, occurred the evening of Aug. 7 when the 38-megawatt plant was cut off from transmission lines and shut down.
PGV said the release was necessary to relieve pressure in the system, but it also occurred while nearby residents were effectively trapped in their homes as fallen trees blocked roadways in and out of neighborhoods.
Blocked roadways also prevented the Fire Department’s hazardous materials team from reaching the site to take hydrogen sulfide readings and stationary monitors were offline because of the power outage.
PGV said its staff took readings as high as 39 parts per billion with hand-held monitors at the site and 25 ppb along the fence line. Its air permit limits the fence line readings at 25 ppb on an average hourly basis.
The gas becomes immediately dangerous to health at 100 parts per million (100,000 ppb), according to the Occupational Safety and Health Administration.
Lower levels can irritate eyes and lungs, and OSHA limits workplace exposure to 20 ppm (20,000 ppb).
Mike Kaleikini, PGV senior director of Hawaiian affairs, said the seven staff members present at the plant during the incident didn’t report experiencing health impacts as a result of the release.
But several neighbors reported experiencing health effects during and after the incident, including scratchy throats, rashes, headaches and even falling unconscious, according to Puna Pono Alliance, which is collecting video testimony from those who say they were impacted.
Tom Travis, vice president of the group, said about 15 have provided testimony so far.
One of those, Michael Hale, said he experienced each of the reported symptoms and smelled a strong rotten egg odor associated with hydrogen sulfide.
“Immediately upon smelling it, we started getting scratchy throats and headaches,” he said.
Hale said he and his girlfriend tried to leave after feeling ill but were unable to because of blocked roadways. After they returned to their Leilani Estates home, within a mile of the plant, he said he “passed out” for nearly 12 hours. Attempts by his girlfriend to wake him were unsuccessful, Hale said.
“She said I looked dead that night,” he said. “My eyes were puffy and red, and I wasn’t waking up.”
It’s not clear yet how much hydrogen sulfide was released.
Kaleikini said the plant was calculating that figure for the state Department of Health. He said he thought it was less than a similar incident that occurred at the plant in March 2013.
When such releases occur, the plant uses abatement measures that reduce the level of hydrogen sulfide by between 95 and 99 percent, he said.
“The steam release facility is designed specifically to respond to a situation such as this,” Kaleikini said. “Our guys responded per all our procedures and did a tremendous job responding, especially given the weather conditions.”
In addition to the controlled release, a smaller 6-inch pressure release valve that is not abated also released steam and got stuck open for about one hour and 45 minutes, he said.
The state Department of Health couldn’t be reached for comment Wednesday, but Hawaii County Civil Defense Administrator Darryl Oliveira said the agency has someone on the island to monitor the plant as it restarts.
Kaleikini said the plant began to ramp up production Monday.
With the concentration unclear, Oliveira said it was difficult to say if unsafe conditions were generated, despite the testimony from neighbors.
“We can’t say how far any release spread,” he said.
Wind speeds were in excess of 40 mph in the area at the time, Oliveira said.
Hale said he has seen a doctor several times since the release. He said tests have come up negative for other potential causes and the tests are not designed to assess hydrogen sulfide exposure.
“There’s no way to test specifically for this poisoning,” he said he was told. “They can only verify these are the symptoms related to (gas exposure).”
In response to the incident, Oliveira said he has requested PGV speak with Hawaii Electric Light Co. about coordinating a plant shutdown prior to the arrival of another strong storm. Civil Defense provided the plant with generators to keep monitors running during power outages, he said.
Civil Defense also is in the process of adding more monitors to the area and providing hand-held devices for a couple of neighbors to use. Additionally, the county is planning to conduct a geothermal health study to assess impacts from the plant.
Travis, a retired naval officer, was also part of a geothermal study group that recommended a health assessment occur.
He said the Puna Pono Alliance, which has been critical of geothermal development, is hoping the video testimony will lead to more action to address the community’s safety concerns.
“Our effort from the very beginning has been to educate people, to try to improve the regulatory structure and get a health study,” Travis said. “Our documentation is going to be used to strengthen both of those efforts.”
Email Tom Callis at email@example.com.