10 April 2010
The Pit of Life AND Death
Must outside Butte, Montana lies a pit of greenish poison a mile and a half wide and over a third of a mile deep. It hasn't always been so - it was once a thriving copper mine appropriately dubbed "The Richest Hill in the World".
Over a billion tons of copper ore, silver, gold and other metals were extracted from the rock of southwestern Montana, making the mining town of Butte one of the richest communities in the country.
When running underground mines became too costly in the 1950's, the drastic but effective methods of "mountaintop removal" and open pit mining were introduced.
As more and more rock was excavated, groundwater-began ot seep into the pit, and pumps had to be installed to keep it from slowly flooding.
By 1983, the hill s so exhausted that the mining company was no longer able to extract minerals in profitable amounts. The Mine was abandoned, the mining company moving to more lucrative scraps of Earth. without the pumps, rain water and ground water gradually began to collect in the pit, leaching out the metals and minerals in the surrounding rock. The water became as acidic as lemon juice, creating a toxic brew of heavy metal poisons including arsenic, lead and zinc. No fish live there, and no plants line the shores. There aren't even any insects buzzing about. The Berkeley Pit had become on e oft he deadliest places on earth,too toxic even for microorganisms.... or so it was thought.
In 1995, an analytic chemist named William Chatham saw something unusual in the allegedly lifeless lake: a small clump of green floating on the water's surface. After examining the slime under a microscope, the researchers identified it as Euglena Mutabilis, a protozoan which has the remarkable ability of being able to survive in the toxic watersof the Berkeley Pit by altering its local environment to something more hospitable. Through photosynthesis, it increases the oxygen level in the water, which causes dissolved metals to oxidize and precipitate out. In addition, it pulls iron out of the water and sequesters it inside of itself. This makes it a classic example of an extremeophile. Extremophiles are organisms that can tolerate and even thrive in environments that will destroy most other living things. Some can even repair their own damaged DNA, a trait which makes them extremely interesting to cancer researchers.
The research team collected water samples, isolated microorganisms, and cultured them. The team eventually identified over 160 different microorganisms.. thus leading to the discovery of a number of promising chemicals. Three of these, berkeleydione, berkeleytrione and Berkeley acid.
the next step was to see what effect these chemicals had, if any, on other living cells. To their delight, five of the chemicals showed anti-cancer properties. Further tests revealed that berkeleydione helped slow the growth of a type of lung cancer cell, and Berkeley acid went after ovarian cancer cells. All five were passed along to the National Cancer Institute for further study.
Other researchers are looking into the Pit as well - not for cancer fighters or other drugs, but simply for ways to help clean the place up. In 1995 flock of migrating snow geese stopped at the massive pond for a rest, and at least 342 of them died there. Authorities now use firecrackers and loudspeakers to scare away migrating waterfowl, but there have been a few smaller die-offs.
The water level is rising at a rate of several inches a month, and if unchecked it will spill over into the areas groundwater in twenty years. That danger has earned the area the dubious distinction of being one of the EPAs largest Superfund sites.
Normally such water is treated by adding lime to the water to reduce the acidity and remove much of the metal, however the Berkeley Pit is so saturated with undesirables that this process would produce tons of toxic sludge every day. Currently the EPAs plan is to focus on containment.
Grant Mitman believes that the best way to clean up the Pit is to use the algae that already lives there. E. Mutabilis, for one, tends to grow in clumps. These clumps clean up their neighborhoods enough for other extremophiles to move in. These organisms would collect the metals within their own cells, and upon dying they would sink to the bottom and drag the metals with them. To Mitman, its all a matter of finding the right mix of extremophiles for a self sustaining algal colony.
With metals concentrated at the bottom, and cleaner water at the top, the Pit could conceivably be reopened. The bottom sludge could be collected and processed for its ever
-more-valuable metal content, and the water could be used for industry or agriculture. While it might not be safe to drink, the water could still be worth a quarter million dollars a year in a water hungry West. In the meantime, the Pit has become a popular tourist attraction.