Drilling nearly finished

By TOM CALLIS

Tribune-Herald staff writer

Drilling at Puna Geothermal Venture is almost done.

“We anticipate being done at the end of May,” Plant Manager Mike Kaleikini said Tuesday.

That should come as a relief to the geothermal power plant’s neighbors.

Drilling has occurred nonstop since March 1.

Noise readings reached 60 decibels Tuesday afternoon, according to PGV’s website.

Kaleikini said the plant is zoned for agriculture, which allows noise levels of up to 70 decibels.

“We do acknowledge that there is additional noise generated,” he said. “We do appreciate our neighbors for putting up with us and hope to get this done completely on schedule.”

PGV is drilling the 6,500-foot well to ramp up production to 38 megawatts at its geothermal power plant in Pahoa.

The drill has reached 5,700 feet.

Kaleikini said the plant is averaging 34 megawatts with its five existing production wells.

“We hope to be able to be at 38 at a regular basis,” he said.

The drill can descend 40 to 50 feet an hour through soft rock.

It can also work as slowly as a few feet an hour when it hits more dense rock.

The well will be about a foot across at the top. The wells narrow as they descend.

PGV has another four wells used to inject steam back into the Earth.

Kaleikini said it will take about two additional months to connect the well with the plant. That work will occur during the day.

Valves prevent steam and gas from being released during and after drilling, he said.

The plant also has over 30 air quality sensors, and employees use hand-held monitors, Kaleikini said.

PGV had a well blowout in 1991.

“Since then we have been required to implement additional safety measures,” he said.

The plant has operated since 1993.

Drilling was scheduled to begin in January and finish mid-April.

“We kicked around the date a few times,” Kaleikini said, adding that the company had to schedule around the availability of contractors.

Email Tom Callis at tcallis@hawaiitribune-herald.com.