Pengelolaan air asam tambang kegiatan pertambangan batubara terbuka dan kemungkinan dampak pada kesehatan kulit masyarakat pemanfaat sungai (Suatu kajian di PT. X, Kabupaten Murung Raya, Provinsi Kalimantan Tengah) = Acid mine drainage management of open pit coal mining activities and possibility impact on skin health of river water-users community (A study in PT. X, Murung Raya District ,Central Kalimantan Province)