Turrialba has been restless since Thursday, and emergency commission members say they are delivering water to those communities nearest the mountain. The ash from the eruptions has polluted the water sources.
In addition schools are being closed as a safety precaution. They are in El Volcán, La Reunión, Sitio Las Abras, Las Virtudes and La Pastora.
The commission, the Comisión Nacional de Prevención de Riesgos y Atención de Emergencias has established a prohibited zone five kilometers around the crater of the volcano.
Scientists also are keeping a close watch. The crater is watched by a series of cameras 24 hours a day.
The volcano has acted up in the past, and there is a good chance the mountain will resume its nap in a few weeks.
Vegetation in the area, which contains many truck farms, has been damaged. Farmers are spraying plants to eliminate the caustic and abrasive ash.
The national park continues to be off-limits, and the commission urged tourists to find other attractions.
The mountain has been emitting primarily ash, gases and water vapor. Some of the eruption columns went 1,000 meters into the sky over the weekend. The ash is being deposited within an area two miles from the crater, the commission said.