What is the Fate of Heavy Metals At the Bottom of Lake Coeur d'Alene Under Anoxic Conditions?
Faculty Mentor Information
Dr. James Moberly and Dr. Andrew Child are both mentors. I, Kasey Peach, am a student.
Presentation Date
7-2017
Abstract
Lake Coeur d’Alene sediments harbor massive amounts of heavy metals due to mining waste upstream in the Coeur d’Alene River. If the lake becomes anoxic, a flux of metals into the water could be observed. Consequently, the lake water could become contaminated with heavy metals. The fate of the metals depends on the competing roles of two anaerobic microbial groups. Sulfur reducing bacteria (SRB) are responsible for sequestering metals in the sediment while iron reducing bacteria (IRB) mobilize metals from the sediment into the water. This project aims to examine how IRB interact with the sequestered metals when SRB are selectively inhibited. To inhibit SRB, various concentrations of molybdate were injected into the systems. Temporal water samples were collected to measure byproducts of microbial activity. The information provided by the study will guide future studies and regional stakeholders in understanding the fate of heavy metals in Lake Coeur d’Alene.
What is the Fate of Heavy Metals At the Bottom of Lake Coeur d'Alene Under Anoxic Conditions?
Lake Coeur d’Alene sediments harbor massive amounts of heavy metals due to mining waste upstream in the Coeur d’Alene River. If the lake becomes anoxic, a flux of metals into the water could be observed. Consequently, the lake water could become contaminated with heavy metals. The fate of the metals depends on the competing roles of two anaerobic microbial groups. Sulfur reducing bacteria (SRB) are responsible for sequestering metals in the sediment while iron reducing bacteria (IRB) mobilize metals from the sediment into the water. This project aims to examine how IRB interact with the sequestered metals when SRB are selectively inhibited. To inhibit SRB, various concentrations of molybdate were injected into the systems. Temporal water samples were collected to measure byproducts of microbial activity. The information provided by the study will guide future studies and regional stakeholders in understanding the fate of heavy metals in Lake Coeur d’Alene.