Deep sulfidic groundwater, Olkiluoto, Finland Metagenome

Olkiluoto, an island off the west-coast of Finland, will host a deep underground repositoryfor the storage of high level nuclear waste. Sulfide production is relatively high in some drillholes at Olkiluoto, which has the potential to compromise the long-term integrity of storednuclear waste. To understand the microbial processes that drive sulfide production, wehave sampled groundwater from three drill holes with high, intermediate and low levels ofsulfide. Combining extensive geochemical data with 16S rRNA and metagenomicsequencing, comparative analyses of these three distinct groundwaters should give aninsight into the key players driving sulfate reduction and the electron donors fueling theprocess. This information will be used to strengthen the safety of the nuclear wasterepository. In addition, metagenomic analyses will be used to reveal the metabolic potentialof poorly characterised and uncultivated microbial phyla detected in this deep terrestrialsubsurface environment. PI Rizlan Bernier-Latmani, Ecole Polytechnique Federale de Lausanne