Presenting Dr Irdika Mansur who is a mining reclamation expert from IPB University, SEAMEO BIOTROP held its 1st Quarterly Public Seminar (QPS) 2019 focusing on the development of mining reclamation technology in Indonesia. The seminar aimed to increase participants' knowledge and understanding on mine reclamation, and became a forum for disseminating information related to the topic. This activity was conducted on 20 February at the Centre’s campus in Bogor, attended by 106 participants coming from various universities, research institutions, government institutions and companies across Indonesia.

At the beginning of his lecture, Dr Irdika conveyed that disruption to the environment cannot be avoided in mining businesses. Interference toward this environment is temporary and must be controlled so that it does not cause a broad and detrimental impact. The ex-mining land must be restored to its function in accordance with its designation, so that the land remains a productive part of the landscape. Dr Irdika said that nowadays various technologies continue to be developed to restore the productivity of ex-mining land and control contamination of mine wastewater. This seminar presented the results of collaboration between BIOTROP and mining companies, and research results conducted by the Centre and himself on the mining reclamation efforts.

Dr Irdika explained that the restoration of ex-mining land includes land arrangement using overburden, spreading soil material, erosion-sedimentation control, revegetation, and plant treatment to ensure that the plants will grow well. The effort is strengthened by regulation and supervision from the government which encourage the mining players to more active in reclamation activity. The establishment of Mine-Environmental Management Forum (FRHLBT and FKPLPI) also supports the acceleration of the deployment of post-mining land reclamation technology. Dr Irdika emphasized that all the process has to be planned and prepared properly, thus, the reclamation process will be successful.

Currently, the mining companies have already been provided with a good system to fulfill all necessaries used for doing reclamation in their ex-mining lands, for instance, seed collection bank, plant nursery, composting site, etc. The plant seeds may be obtained from surrounding forest, nearest research institution, company, and local community. The Multipurpose Tree Species prefers to be planted, such as seasonal fruit plants and woody plants, so that the harvest can be utilized. Dr Irdika also suggested to plant endangered local plants such as agarwood, ebony, Shorea, and merbau, in order toboth restore the land and conserve the species. However, before the land is planted, its infertile soil has to be treated first using organic material to increase the nutrients and the binding capacity of the soil. This will also help in buffering the pH and increasing the number of beneficial soil flora and fauna.

“Each type of mining has different challenges in restoring the land, which needs different handling either. For example, gold mine which produces waste rock dump coated by soil materials with certain thickness, needs trees with roots that widen at the ground such teak, while coal mine uses trees that are acid resistant and can hold inundation such Eucalyptus due to acidic soil and bad drainage resulted from the mining process,” said Dr Irdika.

The planting methods depend on the type of the land. Dr Irdika said that for the flat land, the planting can be done manually using seedlings or seeds with high viability. Meanwhile, hydroseeding and ‘templok’ methods are used for planting the plants in sloping land.

The mining activity sometimes also produces pits which can be filled by water if it is not covered by the soil. To be able to be used, the water has to be treated first using calcium or artificial swamp considering that it may contain high levels of pH and heavy metals. The neutral void is used by the community to cultivate the fish and as a source for drinking water, or it is just thrown away to the public waters.

“To date, mining reclamation technology and innovation in Indonesia continues to be developed in order to reduce the reclamation cost and to increase the quality of the reclamation results. This reclamation efforts are also to restore ecological, economic and social functions. Of course, the synergize among experts, government, mining company, and community is needed to succeed the whole mining management”, concluded Dr Irdika.

Dr Irdika Mansur is a researcher and lecturer at the Silviculture Department of the Faculty of Forestry of IPB University who has conducted research for more than 20 years on reclamation of ex-mining land using a silvicultural approach to manage mine wastewater in Indonesia. Dr Irdika has also served as BIOTROP’s Director since 2015, and continued to establish both study and collaboration in mining reclamation technology.