Sorsogon, Philippines - April 28, 2025 BULUSAN VOLCANO BULLETIN This serves as a notice for raising the alert status of Bulusan Volcano from Alert Level 0 (Normal) to Alert Level 1 (Low-level Unrest). A phreatic eruption occurred from the summit crater of Bulusan Volcano at 04:36 AM today, 28 April 2025, and lasted 24 minutes based on seismic and infrasound records. The event produced a bent plume that rose 4,500 meters above the crater before drifting west to southwest. Ashfall was reported in Brgys. Cogon and Bolos, Irosin and Brgys. Puting Sapa, Guruyan, Buraburan and Tulatula Sur, Juban. A pyroclastic density current (PDC) or “uson” descended the southwestern slopes and travelled within three (3) kilometers from the summit vent. Prior to the eruption, a total of fifty-three (53) volcanic earthquakes were recorded over the 24-hour period yesterday. Rumbling sounds were reported by local government officials approximately 15 minutes before the eruption and were recorded by infrasound sensors. In view of the above, DOST-PHIVOLCS is now raising the alert status of Bulusan from Alert Level 0 to Alert Level 1, which means that the volcano is currently in a state of low-level unrest with chances of phreatic eruptions succeeding this morning’s event. Local government units and the public are reminded that entry into the 4-kilometer radius Permanent Danger Zone (PDZ) must be strictly prohibited and that vigilance in the 2-kilometer Extended Danger Zone (EDZ) on the southeast sector must be exercised due to the possible impacts of volcanic hazards such as PDCs, ballistic projectiles, rockfall, avalanches and ashfall on these danger areas. Communities that experience ashfall must take all necessary precautions and use protective masks or wet cloth to prevent ash inhalation. Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from any sudden phreatic eruption can be hazardous to aircraft. Furthermore, people living within valleys and along river/stream channels especially on the southeast, southwest and northwest sector of the edifice should be vigilant against sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall should phreatic eruption occur. DOST-PHIVOLCS is closely monitoring Bulusan Volcano’s condition and any new development will be relayed to all concerned.