Alert Level 2 is maintained over Taal Volcano, the Philippine Institute of Volcanology and Seismology (Phivolcs) said Sunday.
In its 8 a.m. bulletin, Phivolcs reported weak emission of steam-laden plumes rising 50 to 100 meters high before drifting northeast.
State volcanologists also recorded 22 volcanic earthquakes that are associated with rock fracturing processes beneath and around the volcano.
The earthquakes included one low frequency event associated with magmatic fluids.
"At Alert Level 2, sudden steam-driven or phreatic explosions, volcanic earthquakes, ashfall and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within Taal Volcano Island (TVI) and along its coast," Phivolcs said.
Phivolcs recommended that entry into TVI, Taal’s Permanent Danger Zone, must be strictly prohibited, and advised local government units to assess previously evacuated areas within the seven-kilometer radius for damages and road accessibilities and to strengthen preparedness, contingency and communication measures in case of renewed unrest.
It also advised residents 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 since the ash can be washed away and form lahars along the channels," Phivolcs said.
Since airborne ash and ballistic fragments from sudden explosions and wind-remobilized ash may pose hazards to aircraft, Phivolcs stressed that civil aviation authorities must advise pilots to avoid flying close to the volcano.
Source: Philippines News Agency