Despite the extremely
harsh conditions present in the pit lake, there are a small number of organisms
present that are surviving, if not thriving, in the waters. In 1998,
Grant Mitman, at Montana Tech of the University of Montana in Butte, proposed
a study to examine the diversity of life in Berkeley Pit Lake in order to
establish a baseline community structure. Mitman
hypothesized that the lake’s extreme conditions may accommodate several
undiscovered species among its extremophiles, and that some of the species
present may be ideal for beginning the remediation process of the lake.
Algae are primary producers, and as such can potentially have several positive
effects on the conditions in the lake. As a result of their metabolism,
algae produce HCO3-, which can raise the pH of surrounding water.
Also, the leakage of algal photosynthate can provide a source of organic
C for other microbial organisms. Photoauxotrophs can also oxygenate
water as a result of photosynthesis. Algae may also sorb metals from
water by ion exchange, complexation, or physisorption, or may conduct biotransformation
or enzyme-catalyzed conversion of metals to less toxic compounds3.
Among the organisms that can at present be cultured
from the pit lake are twenty species of fungus (19 molds and 1 yeast), and
numerous bacteria, including several species of cyanobacteria.
A few protists were cultured, although these were assumed to exist only
as cysts/spores in the actual lake. Five species of algae (and possibly
a sixth) were found in the waters. Chromulina freiburgensis Dofl. was
found to be the dominant phytoplankton, and Euglena mutabilis Schmitz was
the major benthic algae. Also present are Chlorella vulgaris Beijerinck,
Chlorella ellipsoidea Gernek, and Chlamydomonas acidophila Negoro4,5,6.
Attempts to identify and culture sulfate-reducing bacteria in the lake for
phytoremediation purposes have to date been fruitless7.
