UMass team to study bioremediation of acid, heavy metals from collapsed mind
Work funded with $1.59 million from the National Science Foundation
AMHERST, Mass. -- Highly acidic drainage from an abandoned sulfide mine in Rowe is slowly cleaning itself over time, and an interdisciplinary research team from the University of Massachusetts Amherst is studying why. The group brings together experts from the fields of microbiology, geology, engineering, and science education, to determine the extent and rate of bioremediation. Researchers say their findings may enable quicker natural cleanups not just at this mine, but at others throughout the country and the world. The interdisciplinary project has received a $1.59-million grant from the "Biocomplexity in the Environment" program of the National Science Foundation. This highly competitive program has funded only 10 projects this year nationwide.
"The mine collapsed in 1911 and filled with groundwater," explained Klaus Nüsslein, assistant professor of microbiology. "The overflowing groundwater drains out of the old mine shafts, and flows down the stream channel." The drainage waters are more acidic than vinegar, with pH values around 2, and carry large loads of metals, including copper, zinc, and iron, Nüsslein said. "In other areas of the country, similar acid-mine drainage from former coal or gold mines can mobilize additional undesirable contaminants." Researchers stress, however, that there is no threat to the local environment or the area's water supply, because the iron sulfide in the Davis Mine contains few hazardous impurities. This makes the site an ideal subject for examining the natural processes that are contained in the drainage. Rowe is located in western Massachusetts, near the Vermont border.
The other UMass researchers involved in the project are Richard Yuretich of geosciences, who is the principal investigator of the project; Sarina Ergas and David Ahlfeld of civil and environmental engineering; and Allan Feldman of the School of Education. Jonathan Lloyd of the University of Manchester, England, is also collaborating, studying a similar abandoned mine in Wales. The group will combine field work, computer modeling, and laboratory research to study the issue over the next five years. In the end, this interdisciplinary group will demonstrate the global importance of using bacteria to clean up the environment.
Nüsslein, a microbiologist, will try to determine which particular microorganisms are oxidizing the acids and heavy metals, providing a natural source of bioremediation. "Obviously these microorganisms are very successful at remediating the site. We want to know which microorganisms are there, which ones are thriving, or just making do, and what their actual function is," he said. Yuretich, a geologist who has brought classes to the site for more than 20 years, will study what role geology is playing in the natural clean-up: "The acid and the heavy metals react with bedrock and other glacial deposits and are neutralized. It's similar to a person with an upset stomach taking an antacid; the acid level drops," said Yuretich.
There are also hydrology issues at work, researchers say. Engineers will study the way the groundwater and surface water are flowing. "There are a series of complex biochemical processes going on in order to enable the bioremediation to take place, and we need hard data to understand those processes," said Ergas. "We need to know the direction of groundwater flow, the amount of water movement, and its chemical composition." added Ahlfeld.
Feldman notes that a strong science education component has been built into the research project. Twelve high-school and middle-school teachers, who are pursuing master's degrees in science education, will work as researchers for spring, summer, and fall, taking what they learn for use in their classroom teaching. "Participation in active research projects is often cited as the best way to learn science and the ways in which scientists think," Feldman said. Surveys and interviews of the teacher-scholars will be used to evaluate their perceptions of the nature of science, engineering, and scientific research. Their K-12 classes will be observed to determine whether their experiences have changed the way in which they understand and teach science, and the effects on their students' learning.