Increased activity at Volcán Turrialba has caused the national emergency commission to take additional measures around the mountain.
The volcano has been having small eruptions up to an average of once an hour.
Officials and scientists fear that something larger is likely.
Most of the livestock from farms and ranches near the volcano are being relocated. One school in the community of El Centro is being closed. Students from a second school are being transferred to an institution further away.
Animal health officials said that there were 279 cows within two kilometers of the volcano. Most are milk cows.
This is not a bad development for the animals because the pastures in the vicinity of the mountain are covered with volcanic ash. Farmers with crops in the field have had to spray the plants each day to wash off damaging ash.
Some of the trees and bushes near the volcano have suffered considerably from the acidic vapor generated by the rain and the volcano.
The Comisión Nacional de Prevención de Riesgos y Atención de Emergencias has established a second ring with a five-kilometer radius around the mountain. Inside this ring residents are being instructed on emergency procedures and local emergency committees have been formed. The
commission gave a summary Monday of its efforts to date.
The Ministerio de Obras Públicas y Transportes reported that it has invested more than $1 million in improving the roads around the volcano so that they are suitable for a hasty evacuation.
The mountain continues to be under heavy surveillance, and every microquake beneath the volcano is logged and studied.
There is a probability that the volcano will simply return to sleep, although volcano scientists are predicting at least a small eruption. The major damage in the past has been the grounding of aircraft at Juan Santamaría airport due to deposits of ash.