Members of the Institute for Advanced Learning and Research’s (IALR) Applied Research team met with Altavista’s town council in October to go over a proposal that would remediate contaminants in the town’s overflow pond. The proposal was approved on November 11 for the amount of $36,000.
Under the proposal, scientists at IALR would use an “in situ” approach to treat PCBs (polychlorinated biphenyls) by planting switchgrass in the soil and inoculating the plants with beneficial bacteria that can break down the PCBs. The expectation is that the switchgrass roots would secrete sugars to keep the bacteria alive, which inoculates the soil, as well as spread the bacteria as the roots grow, thus fighting PCBs with two techniques.
“It might not work but we won’t know until we try,” IALR’s Director of Applied Research, Michael Duncan said.
IALR scientists Chuansheng Mei, Ph.D. and Scott Lowman, Ph.D. have eight years of experience researching switchgrass and bacteria and have strong confidence in this process. Their research on switchgrass has already led to multiple publications in scientific journals.
According to Lowman, “switchgrass was selected because it is perennial with an extensive root system that penetrates the soil completely and can do well in flooding.”
For many years prior to 1977, PCBs were unknowingly deposited into the town’s 6.1 acre overflow pond adjacent to the waste water treatment plant from nearby industries. The use of PCBs was outlawed that same year.
In 2002, the town entered the Department of Environmental Quality’s voluntary remediation plan to reduce the PCB levels. Lowman, who was involved in another remediation project in Lynchburg, followed the town’s involvement in the program and wanted to help.
The project will begin immediately with field and lab research on the proposed method. IALR will also review reports on experiments already done on the pond, as well as create a risk mitigation report, which is a set of guidelines to follow at the pond to reduce risks, such as people covering their shoes so PCBs aren’t transported outside of the area.
The proposed experiment is expected to last 18 months. Scientists will set up four groups with various combinations of switchgrass and bacteria, as well as controls. Each group will have 15 pots with the same soil and PCB mixture, totaling 60 pots. The pots will be set adjacent to the pond in the winter with the grass planted in the pots in the spring.
Samples will be taken in July, the following winter and then July 2016, ending the first phase of the study. If the results are favorable, a phase two may be initiated on a larger scale.
“This is a worldwide problem,” Lowman said. “If this project is successful, it would not only benefit the town of Altavista but many other localities as well. It also represents IALR’s commitment to the health and prosperity of the region.”