As part of a national development program at the end of 1980s local governments from Southern Costa Rica (Golfito and Osa) signed an agreement with Stone Forestal Company a subsidiary of the US-based company Stone Container. The agreement consisted to plant 24 million of gmelina arborea or "Melina trees" ( raw material for paper production) across 24, 000 ha of rented farmland along the Southern Pacific Coast. It also included the permission for the building of a shipyard and a seaport to manufacture and export the material to the United States of America. According to Stone Forestal, around 6000,000 tonnes of splinters would be cut and exported where they would be turned into film paper, newsprints, toilet paper or boxes.
At that time, the Costa Rican environmental justice organization the Asociación Ecologista Costarricense (AECO) was concerned on the one side about the renting of the farmland for tree plantations preventing the growing of foodcrops, but also on the other side about the environmental impacts that both tree plantations, the construction of a shipyard and the seaport would have in a very biodiverse and unique ecosystem such as Golfo Dulce. In early 1990s AECO in hand with local communities and scientists began to gather data about the possible environmental impacts of the project and in 1993 launched the campaign "Salvemos el Golfo Dulce" which attired the attention of international supporters such as Greenpeace and Rainforest Action Network. In 1994 the Greenpeace´s ship visited the Golfo Dulce and the campaign became more popular.
When the incoming president (José María Figueres) arrived in 1994, the Sala Constitutional declared illegal the permissions given to Stone Forestal and denied the building of the seaport and the shipyard which made the plantation itself nonprofitable for the company. In 1995, only 13,000 ha from the 24.000 planned were planted.
After the environmental justice victory, on December 6th, 1994 three environmental leaders: María del Mar Cordero, Jaime Bustamante and Oscar Fallas from AECO died in a fire in their home. The causes of the fire are still unknown and it was declared by the Costa Rican institutions as "an accident". However, environmentalists, claim that it was provoked and that their dead it is related to their environmental struggle against Stone Forestal. After this episode, another environmental leader from AECO (David Maradiaga) was found dead in a park, the causes of his death are also unknown.
The struggle against Stone Forestal in Southern Costa Rica represented a landmark victory for the Costa Rican environmental justice movement but also a debt of the CostaRican institutions for not been able to give clear and accurate data about the death (or murder) of four environmental defenders.