MANILA (3rd UPDATE) - Taal Volcano's status was lowered to alert level 3 on Sunday morning as state seismologists monitored a decreased tendency towards hazardous eruption, Phivolcs officer-in-charge Renato Solidum said.
"Ang pagbaba sa alert level 3 base sa mga parametrong binabanatayan ay nagpapakita ng pagbaba ng tendency towards towards hazardous eruption," Solidum told DZMM.
"Pero ito po ay hindi nangangahulugan na ang aktibidad ng Taal Volcano ay tumigil na, o di kaya'y ang banta ng mapanganib na eruption ay nawala na po. Nandyan pa po," he added.
On Jan. 12, Phivolcs raised the alert level over Taal from Level 1 to 4 due to magmatic unrest, prompting mandatory evacuation of residents in areas within its 14-kilometer radius. Alert level 4 warns of a hazardous explosive eruption possibly within hours to days.
In its 8 a.m. bulletin on Sunday, Phivolcs said "Taal Volcano's condition in the two weeks following the 12-13 January 2020 phreatomagmatic eruption (main eruptive phase) has generally declined into less frequent volcanic earthquake activity, decelerated ground deformation of the Taal Caldera and Taal Volcano Island edifices and weak steam/gas emissions at the Main Crater."
Solidum urged residents to stay away from the volcano's 7-kilometer radius as it lowered the alert level.
He advised local officials to assess damages and roads in areas outside the prohibited area following the occurrence of fissures, which indicated the flow of magma underground.
"'Yung aktibidad na nakikita natin sa main crater ay humina pagkatapos po ng mga pagsabog. Mga usok na lang ang lumalabas," he told reporters.
"'Yung bagong magma ay nandun lang at nagde-degas at mukhang nandun muna siya sa kasalukuyan."
Residents of all towns under lockdown except Agoncillo and Laurel, which are within the 7-kilometer radius, may return to their respective residences or places of work, Batangas Gov. Hermilando Mandanas told reporters.
"It is still possible that Taal Volcano may still erupt. Therefore, all returning residents must be constantly alert, vigilant and ready to evacuate within one hour," he said.
In an advisory, Mandanas identified the following as areas where residents have the option to return: Alitagtag, Balete, Cuenca, Lemery, Lipa City, Malvar, Mataas na Kahoy, San Nicolas, Sta. Teresita, Taal, Talisay, and Tanauan City.
The volcano island remains on permanent lockdown.
Taal Volcano continued to emit white steam-laden plumes on Sunday morning after it spewed an increased amount of steam and sulfur dioxide that reached 100 to 800 meters high on Saturday.
The release of steam and ash, however, was not accompanied with volcanic earthquakes, according to Solidum.
"Ang importante ang mga tao na nasa paligid ng taal volcano ay dapat mabilis ang mga aksyon, dapat handa sa kanilang gagawin, maayos ang kanilang contingency measure," Solidum said.
Residents warned against lahar
Solidum also warned those residing near rivers of the occurrence of lahar following heavy rainfall.
"Lalo na yung sa western side, sa baba ng Tagaytay ridge, kung may abo po sila, baka maibaba yung abong yun. Delikado po sa lahar," he said.
"Ang reminder namin ay dapat handang-handa ang mga tao at komunidad in case na mag-escalate ulit."
Taal's alert level may be further downgraded to level 2 (which indicates probable magmatic intrusion, that could eventually lead to an eruption; but may also lead to level 1 if there is further decline in the trend) if the volcano's activity continues to decrease in 2 weeks, Solidum said.
Level 1 means there is magmatic, tectonic or hydrothermal disturbance but eruption is not imminent. At the highest level of 5, meanwhile, a hazardous eruption is already in progress.
Earthquakes recorded across the Taal region by the Philippine Seismic Network (PSN) declined from 959 to 27 events per day, ranging between magnitude 2.1 to 4.1, from Jan. 12 to Jan. 24, Phivolcs said in its bulletin.
The Taal Volcano Network, which can record small earthquakes undetectable by the PSN, also recorded a decrease in activity to 420 events per day from 944 between Jan. 17 and 24, it added.
Taal's unrest has displaced more than 376,000 people from Batangas, Cavite, Laguna and Quezon, according to the National Disaster Risk Reduction and Management Council.
-- With reports from Bianca Dava, ABS-CBN News