UPDATE: 10:15 a.m.

Trace ashfall over the Kau district from Kilauea volcano is still possible today.

“Web cams, observers and radar data indicate that occasional small bursts of volcanic ash continue to emanate from Halemaumau Crater,” said weather officials in a National Weather Service bulletin. The communities of Pahala, Wood Valley and Naalehu are most likely to be affected.

9:10 a.m.

Two CH-53E Super Stallion helicopters have been deployed to Hilo by the U.S. Marine Corps in support of Joint Task Force 5-0, the military force assisting Hawaii County with the current Kilauea eruption.

Each CH-53E can carry more than 50 passengers at a time. “The additional helicopter support from USPACOM and MARFORPAC provides the County of Hawaii and Hawaii’s Joint Task Force-50 tremendous capability,” said JTF 5-0 commander, Brig. Gen. Kenneth Hara. “We now have the capacity to evacuate all of the estimated population of lower Puna south of the lava flow within a few hours.”

9 a.m.

Hawaiian Volcano Observatory scientists say the eruption of lava in the Leilani Estates and Lanipuna Gardens subdivision continues today with the middle portion of the fissure system, near Pohoiki Road, producing “the most robust eruptive activity in the Lower East Rift Zone.”

They said several fissures between Luana and Kaupili streets, reactivated and are spattering.

At Kilauea volcano’s summit, small ash emissions from the Overlook crater continued overnight, with ash emissions reaching 6,000-feet elevation “during the most energetic explosions … but dispersed quickly,” an HVO morning update said. “Moderate trade winds were blowing to the southwest and light ashfall likely occurred in downwind locations.”

6 a.m.

Lava continues to erupt from fissures in Leilani Estates and Lanipuna Gardens subdivisions, but has not advanced further onto Puna Geothermal Venture property.

County, state and federal crews continue to monitor the area around PGV for sulfur dioxide and hydrogen sulfide gas, but have not detected any of the latter.

The middle of the fissure system continues to produce the most “robust” eruptive activity in the Lower East Rift Zone, according to the Hawaiian Volcano Observatory.

The lava fountains from fissure 22 feed a single lava channel that enters the coast just north of MacKenzie State Park. Fountains are also erupting from fissures 5, 6, 13 and 19 and continue to feed a lava flow advancing to the south along the west side of fissure 22 flows that reached the ocean late Wednesday afternoon.

Volcanic gas emissions remain very high from the fissure eruptions.

WEDNESDAY, MAY 23

6 p.m.

A new lava flow is expected to enter the ocean east of MacKenzie State Park tonight, the Hawaiian Volcano Observatory geologists report.

HVO scientists say that eruption activity continues in the Lower East Rift Zone, with flows and ground cracking continuing in Leilani Estates and Lanipuna Gardens.

Officials said the lava situation near the shuttered Puna Geothermal Venture plant remains stable, and that county, state and federal crews are monitoring the area for sulfur dioxide and hydrogen sulfide.

Free masks for ash protection are still being distributed as ash emissions continue at Kilauea’s summit:

>> Distribution runs tonight through Friday from 3:30 p.m. to 7:30 p.m., and Saturday from 9 a.m. to 1 p.m.

>> Masks will be distributed at the Ocean View, Naalehu, and Pahala community centers, the Cooper Center, and Shipman Gym in Keaau.

>> Each person may receive up to three masks.

>> Officials warb that masks do not protect against gases and vapors, but provide filtering for ash.

PREVIOUS COVERAGE

An air evacuation of the portions of Lower Puna that are threatened by the Kilauea volcano eruption could be accomplished within four hours if that becomes necessary because of damage to ground transportation routes, according to Hawaii Army National Guard commander Brig. Gen. Kenneth Hara.

In a briefing this morning at Hawaii County Civil Defense headquarters, Hara told state, county and federal officials that he has arranged for two Sikorsky CH-53 Sea Stallion helicopters to be available for evacuation missions now that lava from the Lower East Rift Zone has flowed to the sea and severed Highway 137 along the coast.

The movement of that river of the lava means there is only one ground evacuation route available left for an estimated 1,000 residents who are still in homes scattered across on thousands of acres of rural land in the Kalapana area, including Opihikao, Black Sand Beach subdivision, Kalapana Seaview Estates, Puna Beach Palisades and Kahena.

Janet Snyder, spokeswoman for Hawaii Island Mayor Harry Kim, said the Sea Stallions can ferry up to 43 people out of the area at a time. One of the helicopters is already on Hawaii island, and the other is expected to arrive today, she said.

“They can basically evacuate a whole subdivision of 500 people within two hours,” Snyder said.

Hara has been appointed head of a “dual-status command Joint Task Force 5-0” in response to the eruption, an arrangement gives him authority to command both National Guard and active military forces to carry out operations in response to the emergency in Puna.

Hara reported that he can also call on Sikorsky UH-60 Black Hawk helicopters from the 25th Combat Aviation Brigade at Wheeler Army Air Force Base on Oahu if they are needed.

An air evacuation is emerging as a real possibility because scientists know that lava has been passing beneath Highway 130 along the East Rift Zone and surfacing in areas in and around Leilani Estates since the latest eruption began on May 3.

That suggests it is possible new fissures could open west of Leilani that would cut Highway 130, leaving a large area from MacKenzie State Recreation Area to Kalapana without a ground evacuation route.

Hawaii Civil Defense Agency Administrator Talmadge Magno said Tuesday the cracks in Highway 130 that closed the route for a time earlier this month have not been widening. The highway reopened after crews dropped steel plates across the cracks to provide safe access for traffic.

“Our state highways folks and our public works folks say they can try to keep it open as long as possible,” he said. “Right now, they’ve got the steel plates on it. Whether it is dumping out huge quantities of material just to fill cracks and so forth, they’ll do it.”

“We’re looking at some alternate routes, but everything’s going to have to cross that East Rift, so we’re limited on alternatives, but part of our messaging all the time has been to let these people know that this is coming down, that possibly they’re going to get isolated, so they need to make that decision,” Magno said. “If you need to be in Hilo or another place for work, you need to start considering moving out.”

The one road that could direct traffic away from the East Rift eruption area is Chain of Craters Road. State and federal officials have been planning to reopen that route, which extends from Kalapana to the Hawaii Volcanoes National Park, but construction has not yet begun on that project.

Chain of Craters was reopened by the county as an emergency access route when another lava flow threatened Pahoa in 2014 and 2015, but lava from Kilauea has once again blocked the route. The flow that caused the latest blockage ceased last year.

Gov. David Ige told reporters Tuesday that “we are evaluating reopening Chain of Craters Road, but it’s a very dangerous road, it hasn’t been used for a long time, so we do have county and highway people really looking at it and trying to prepare it should it be necessary.”

Ige said transportation officials are “also looking at other alternative routes and trying to decide what would make the most sense in terms of providing safe passage. We do know that we need to keep roads open so that residents can get around, and we’re committed to doing that in the best and safest way that we can.”

In other volcano-related developments today:

>> County, state and federal partners are working together to monitor the situation at Puna Geothermal Venture, according to the Hawaii County Civil Defense. State and county departments working with PGV continue to work to install mechanical plugs into the shafts of 10 geothermal wells to further secure them.

>> The middle portion of the fissure system continues to produce the most robust eruptive activity in the Lower East Rift Zone, according to the Hawaiian Volcano Observatory. Although a faint glow was seen from fissure 9, no flows or methane was observed burning in road cracks overnight. The ocean entry remains active, producing occasional small explosions. And the raised lava pond has reached 36 feet above ground level, according to observers. Volcanic gas emissions remain “very high” from the fissure eruptions, the HVO said.

>> The Leilani Estates subdivision continues to see ground cracking and the eruption of lava, with the potential for new lava outbreaks in the area, according to the Hawaiian Volcano Observatory. The most active fissures Tuesday were 22, 19, 6, 5 and 23, HVO officials said. Meanwhile, activity at fissure 17, at the northeastern end of the fissure system, has eased up. Magma continues to be supplied to the lower East Rift Zone, and fissure 6 is feeding a flow to the south, roughly parallel to the western flow from fissure 22. Although there were only a few earthquakes Tuesday in the rift zone, overall earthquake activity remains elevated.

>> Volcanic gas emissions at the summit remain high, and “additional explosive events that could produce minor amounts of ashfall downwind are possible at any time,” according to the HVO.

>> RELATED VIDEO: An enormous lava lake, threatening conditions at the Puna Geothermal Venture and high levels of sulfur dioxide and hydrogen sulfide billowing in the air prompted Hawaii County officials and the Hawaii National Guard to cancel all media tours into the areas affected by the lava from Kilauea Volcano that is advancing towards the geothermal power plant wells. (Video courtesy State of Hawaii, Dept. of Defense; mobile app users, click here)

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