After the decisions to select the Centiri Area for Semi-Detailed Explorations made by the Working Committee of the Central Sumatera Coal Explorations Project on June 6, and by the exclutive Council on June 8, 1987, the field work was commented on March 9, 1988.
the directorat general of mines ,and the directorate general of geolgy and mineral resources of the departement of mines and energy of the republic of indonesia ,and new energy Develovement Organization ,japan,Concluded the agreement On Central sumatera Coal exploration Project ,CTA-156,On October 9 ,1986 at jakarta.