State volcanologists on Tuesday lowered Mayon Volcano’s alert level from four to three after nearly six weeks.

In an advisory, the Philippine Institute of Volcanology and Seismology (Phivolcs) said Alert Level 3 means there is decreased tendency towards hazardous explosive eruption but should not be interpreted that unrest has ceased.

"Mayon Volcano’s condition in the past week has been characterized by a general decline in unrest reflected by moderate seismicity and degassing, deflation of the edifice and a decrease in eruptive activity at the summit crater," it said.

The agency added volcanic earthquakes, magmatic gas output and weak surface processes such as sporadic degassing and lava effusion events, steam-driven explosions, rockfall and PDCs ( pyroclastic density currents) can still be expected.

Phivolcs reminded the public that at Alert Level 3, sudden explosions, lava collapses, PDCs and ashfall can still occur and threaten areas in the upper to middle slopes of Mayon.

It said that if "the potential for hazardous explosive eruption be forewarned by an uptrend or pronounced change in monitoring parameters, the Alert Level may be raised back to Alert Level 4."

"Conversely, should there be a persistent downtrend in monitoring parameters, then the Alert Level will be further lowered to Alert Level 2." Phivolcs added.

Phivolcs recommended that entry into the six-kilometer danger zone and a precautionary seven kilometer-radius extended danger zone in the south-southwest to east-northeast sector, from Anoling, Camalig to Sta. Misericordia, Sto. Domingo, should still be prohibited.

The regional Office of Civil Defense said decampment of thousands of evacuees living in the 7 to 8-kilometer extended danger zone radius will officially start tomorrow.

In a TV interview, Albay Governor Al Francis Bichara said around 16,000 families were allowed to go home, while more or less 3,000 famillies would remain in evacuation centers until Phivolcs lowers the alert level to 2.

"We have advised mayors they can start decamping evacuation centers. Some have gone home, some are scheduled to go home," Bichara said.

He added Albay received P100 million worth of donations.

"So many generous donors provided relief goods. The evacuees have enough, but they want to go home," he said.

Albay Public Safety and Emergency Management Office chief Cedric Daep said crop damage because of ash fall from the volcano reached P86 million pesos. Ella Dionisio/DMS