MANILA, Philippines — The Philippine Institute of Volcanology and Seismology (Phivolcs) yesterday warned that based on the steam release and number of quakes of Mount Bulusan, more phreatic eruptions are possible in the next days or weeks.
Phivolcs director Renato Solidum Jr. said steaming or continuing hydrothermal activity at Mount Bulusan indicates the possibility of another phreatic eruption, as the volcano is considered to be still in a “very active” state.
The phreatic eruption episode can be seen in multiple explosions and can be “days or weeks in between.”
“In terms of volume expelled, the steam might be greater because of the six vents where it came out. The record of earthquakes that we have would show that the activity on June 12 was more energetic than last June 5,” Solidum said over CNN Philippines’ “The Source.”
Solidum said ash from Mount Bulusan also reached Naga, about 70 kilometers away, because the wind was stronger during the June 12 phreatic eruption. Asked if a magmatic eruption is possible, he noted that there are no indications so far, but Phivolcs will check if there is magma involved by examining the ash that was released.
According to him, the last Bulusan magmatic eruption happened some 200 years ago, which also doesn’t really mean that another one may be imminent.
Phivolcs said 106 volcanic earthquakes, including 48 volcanic tremors lasting for 20 minutes, have been monitored from Sunday to Monday. On June 12, Bulusan’s sulfur dioxide (SO2) emission rose to 4,627 tons from the previous emission of 615 tons, and its plume scalded up to 500 meters tall from the previous 150 meters.
Phivolcs Sorsogon said that fluctuating parameters were indications that Bulusan’s abnormal condition is sustained.
Under Alert Level 1, entry into the four-kilometer radius Permanent Danger Zone (PDZ) and entry without vigilance into the two-kilometer Extended Danger Zone (EDZ) is still prohibited, while flying any aircraft close to the volcano is not allowed.
More residents evacuate
Fearing a stronger ash explosion in the coming days, more residents in the ashfall-hit areas have been asking disaster management officials in Sorsogon to be evacuated to safer ground.
Sorsogon Provincial Disaster Risk Reduction and Management Office (PDRRMO) chief Radeen Dimaano said that until 2 p.m. yesterday, at least 475 persons in Juban had already moved to the designated evacuation centers.
He said they were expecting more evacuees as some residents signified their intention to move to safer areas for fear of stronger explosions in the coming days.
Meanwhile, some 60 families living within the four-kilometer PDZ will not have to be relocated as concerned local government units (LGUs) are already working on a resettlement program, according to National Disaster Risk Reduction and Management Council (NDRRMC) spokesman Mark Timbal.
According to him, despite another Bulusan phreatic eruption, no damage to infrastructure is expected since the only problem was the ashfall that briefly caused zero visibility at the height of the eruption.
Timbal also warned the public against fake donation drives for the benefit of affected families but eventually end up for the personal use of unscrupulous individuals or groups.
For his part, outgoing Sorsogon Gov. Francis Escudero disputed yesterday the national government’s P20-million damage to agriculture assessment in the province due to Mt. Bulusan’s phreatic explosion.
Escudero said the P20-million assessment is way higher than the estimate of their agricultural officer, which is at P1.6 million. “I don’t know where that came from, that was reported by the NDRRMC,” Escudero said over ANC.
Escudero added only two of the 541 barangays have experienced heavy ashfall and that clearing operations are ongoing to clear chapels, schools, roads and other areas. “We expect the cleanup to be finished in a day or two,” he said.
Rescheduled flights
The Manila International Airport Authority Media Affairs Division said eight incoming and outgoing international flights were rescheduled last Sunday due to the volcanic activity of Mt. Bulusan.
As a precautionary measure against the danger posed by Mt. Bulusan’s ash to aircraft engines, the following international flights were rescheduled: Jetstar Asia flights 3K 1765 and 1766 from Singapore to Manila-Singapore, Korean Airlines flights KE 623D and KE 624D from Incheon-Manila Incheon, Asiana Airlines flights OZ 7031 and OZ 7041 from Incheon-Manila-Incheon and Jeju Air flights 7C2305 and 7C 2306 from Incheon-Manila-Incheon.
Last Sunday, 10 domestic flights from Cebu Pacific (CEB) and its sister company Cebgo, and PAL Express were canceled. Phivolcs earlier advised civil aviation authorities to avoid flying close to the volcano’s summit. – Rudy Santos, Cet Dematera, Michael Punongbayan, Emmanuel Tupas