The bioleachings of chalcopyrite ore were compared after inoculating different cultures enriched from the original acid mine drainage sample. The results showed that the higher bioleaching performance was achieved for inoculation with the enrichment D (0.5 % S, 2 % iron and 1 % chalcopyrite) compared to other enrichment systems. The generated ferric precipitation during bioleaching had a key in...

Five acidophilic protozoa (three flagellates, one ciliate and one amoeba) were isolated from acid mine water and a coal biotreatment plant, and grown in mixed cultures with acidophilic bacteria. Cultures were routinely maintained in ferrous sulphate media: in media containing pyrite or pyritic coal, protozoa grew in cultures containing coarse-grain (61-200 pm) but not fine-grain (c 61 pm) miner...

The Richmond Mine at Iron Mountain, Shasta County, California, USA provides an excellent opportunity to study the chemical and biological controls on acid mine drainage ~AMD! generation in situ, and to identify key factors controlling solution chemistry. Here we integrate four years of field-based geochemical data with 16S rRNA gene clone libraries and rRNA probe-based studies of microbial popu...

We evaluated the depth-dependent geochemistry and microbiology of sediments that have developed via the microbially-mediated oxidation of Fe(II) dissolved in acid mine drainage (AMD), giving rise to a 8-10 cm deep "iron mound" that is composed primarily of Fe(III) (hydr)oxide phases. Chemical analyses of iron mound sediments indicated a zone of maximal Fe(III) reducing bacterial activity at a d...

P r e v i o u s s t u d i e s of t h e o x i d a t i o n of i r o n p y r i t e and t h e subsequent r e l e a s e of a c i d i t y i n t o mine d r a i n a g e w a t e r s have provided no c o n c l u s i v e r e su l t s i n a s c e r t a i n i n g which of t h e s t e p s i n t h e o v e r a l l r e a c t i o n i s r a t e d e t e r m i n i n g . Although microorganisms have f r e q u e n t ...