Despite the lower alert level of Taal Volcano, State volcanologists yesterday advised local officials that entry into the seven-kilometer danger zone around the volcano island and lakeshore communities should remain strictly prohibited as hazards can still occur.
The Philippine Institute of Volcanology and Seismology reminded the public that sudden steam-driven and even weak phreatomagmatic explosions, volcanic quakes, ashfall, and lethal volcanic gas expulsions can still occur and threaten areas within and near Taal Volcano island.
Phivolcs on Sunday lowered the alert level of Taal Volcano from four to three, two weeks after its eruption, which forced thousands of families to evacuate due to thick ashfall that blanketed nearby towns.
Authorities had earlier said the tendency towards a hazardous eruption had decreased, noting that Taal’s condition in the past two weeks generally declined into “less frequent volcanic activity, decelerated ground deformation of the Taal Volcano caldera and Taal Volcano island, edifice, and weak steam gas emissions from the main crater.”
Phivolcs yesterday observed weak to moderate emission of white steam-laden plumes that reached 50 to 800 meters high that drifted northeast.
There was lower sulfur dioxide level at 87 ton per day, while volcanic quakes recorded by the Taal Volcano Network also decreased, with 170 tremors plotted, including four low-frequency earthquakes.
Phivolcs advised local government units to “assess areas outside the seven-kilometer radius for damages and road accessibilities and to strengthen preparedness, contingency, and communication measures in case of renewed unrest.”
Residents were also advised to observe precautions due to ground displacement across fissures, frequent ashfall, and minor earthquakes.
Communities beside active river channels, particularly where ash from the main eruption phase has been thickly deposited, should increase vigilance when there is heavy and prolonged rainfall as ash can be washed away and form lahars along the channels, Phivolcs added. (Alexandria San Juan)
