MVO reported that seismic levels from Soufrière Hills were relatively low during 1-8 August. Sulfur dioxide emissions (tons per day) were significantly higher than emissions prior to the partial lava-dome collapse on 28 July. Unconfirmed reports indicated the presence of an ash plume on 3 August. A small ash cloud was seen on 7 August.
Further investigation of the 28 July event revealed that the total amount of material that collapsed from the dome was about 200,000-300,000 cubic meters. Satellite radar images indicated that the vent above Gages wall was enlarged by the explosion to about 150 x 60 meters, elongated E-W. Precautionary access restrictions for areas in and around Belham valley were lifted because evidence suggested that the dome had not been destabilized due to the event.
A new Hazard Level System, designed by MVO and Disaster Management Coordination Agency (DMCA) in consultation with the Government of Montserrat and community groups, was implemented on 8 August. The system divides the southern two-thirds of the island into six zones, and includes two Maritime Exclusion Zones. The Hazard Level ranges from 1-5 and is set by the National Disaster Preparedness, Response, and Advisory Committee (NDPRAC) with advice from MVO. The Hazard Level restricts access into each of the zones depending on the number assigned and is unrelated to the Alert Level. The current Hazard Level was 3.
Source: Montserrat Volcano Observatory (MVO) – “Reports provided courtesy of the Smithsonian’s Global Volcanism Program and the US Geological Survey’s Volcano Hazards Program.”