Water Resources Research Act Program

Details for Project ID 2010ME228B

Microorganisms that can alter groundwater chemistry in an arsenic enriched aquifer

Institute: Maine
Year Established: 2010 Start Date: 2010-05-01 End Date: 2010-10-31
Total Federal Funds: $4,999 Total Non-Federal Funds: $2,264

Principal Investigators: John Peckenham

Project Summary: An aquifer in Northport, Maine has naturally occurring elevated levels of arsenic. Microorganisms may release arsenic in groundwater by reducing bedrock surface coatings or by altering arsenic speciation, thus affecting the sorption of arsenic. Currently there is competing evidence whether microbially mediated iron or arsenic reduction is more important for arsenic release. This work will determine the relative importance of iron and arsenic reduction within the Northport aquifer. Clone libraries for two sampling dates are being constructed to examine changes in the composition of the microbial communities between low arsenic recharge wells and high arsenic discharge wells to assess the impact microorganisms may have on the groundwater chemistry of the aquifer. Since little is known about the long term stability of microbial community structure in a groundwater environment this work will examine the temporal shifts in the microbial communities within the Northport aquifer. The importance of microbial arsenate reduction and arsenite oxidation is will be examined using quantitative PCR and culturing techniques.