In the last few years, the concerns on mercury pollutant of Kapuas River awareness have grown from the environmentalist groups as well as the whole stakeholders. The sources of mercury pollutant are from small scale gold mining which is considered as illegal.
So far, the efforts to prevent water pollution and environmental destruction are in failure as a result, the damage is continuous with no promising solution.
Kapuas River, which criss-crosses west Kalimantan province, has long been recognized supporting either conventional or non-conventional activities. Mostly, it has been utilized for domestic use and industry.
However, in 1998, since the economic crisis hit Indonesia along with the claims of reformation era, have made the local people considered that the gold mining activity in Kapuas River as the most promising sector to support their economy. As a result in the last ten years, the illegal gold mining has been dramatically bloomed.
In the gold mining process, mercury is used as the chemical agent to perform amalgam, which facilitates the separation of gold from the unwanted materials. Hence, Kapuas River is undergoing environmental and social problems due to poor mining practices and lack of economic alternatives.
Kapuas River is found crisscrossed the West Kalimantan and constructed from many tributaries, some of them, Embaloh, Manday, and Kapuas Hulu are located in Kapuas Hulu. Kapuas Hulu is the regency whereby the upstream of Kapuas River is located, while the downstream regencies of Kapuas River are represented with Sanggau regency and the city of Pontianak.
Hence, most of the mercury assessments were designed to cover such regions. According to the research of Mardan Adijaya (Centre for Freshwater and Coastal Studies, Tanjungpura University, West Kalimantan) and Takao Yamashita, based on data from the time periods from 1995 to 2003, the monthly discharge of Kapuas River ranges between 1964-9432 m3/s. It is seen that the flow is dropped during May, June and July, and its highest ranges appear on November and December.
This trend is crucial not only to plan mercury content monitoring periods but also to generate a reliable assessment of pollution load.Small scale gold mining by the indigenous mineral exploitation of the rivers is known as the common practices in developing countries. Bugnosen (1998) suggested that the small scale gold mining is mostly labour intensive which engages a large number of men and women, over six million world-wide.
It has been believed as a safety net in the current economic crisis. Most of small scale mining is unregulated and illegal. It is called PETI (Penambangan Emas Tanpa Izin) in Indonesian.The mercury pollution from gold mining and processing plants causes the contamination of aquatic and terrestrial resources by inhalation and uptakes.
The mercury is used in the amalgamation of gold. The contamination is come from the amalgamation process wastes and from the evaporation of the roasting process. No proper protection and care is adopted to guard against poisonous mercury.
Commonly, the mercury pollution of gold mining is viewed as the emission halo. The survey on the parties contributed in illegal gold mining which is conducted in 2001 reported that there are more than 449 labours and 100 investors involved in Kapuas Hulu.
The mining took place in Bunut Hulu river; Banut river, Nanga Suruk Village, Bunut Hulu sub-district; Tebaung river, Nanga Sebilit, Bunut Hulu sub-district, Mentebah river, Selaub, Bunut Hulu sub-district, Embau river, Mentawit Village, Hulu Gurung sub-district; and Embau river, Mentawai Village, Hulu Gurung sub-district.
