1. Ka Jerker Jarsjö, Josefin Thorslund and Jan Pietron Dept. of Physical Geography and Quatenary Geology, Stockholm University e-mail: jerker.jarsjo@natgeo.su.sejerker.jarsjo@natgeo.su.se Quantifying water-borne spreading of elements in the Lake Baikal Basin

2. Stockholm University Department of Physical Geography and Quaternary Geology:  One of the major departments within the Faculty of Science at Stockholm University  Has approximately 120 employees and educates approximately 1500 students annually  Main research disciplines are Climatology, Ecological Geography, Geographical Data Processing, Geomorphology, Glaciology, Hydrology, Remote Sensing, Tropical Geography, and Quaternary Geology,  Education is oriented towards geography and geosciences, including hydrology and environmental protection. Hydrology group: 1 professor (hydrology, hydrogeology and water resources), 3 assistant professors, 5 post-docs/researchers, 16 PhD students

3. Collaboration Field campaigns, joint modeling and analysis work: Moscow State University, Faculty of Geography, Dep. Hydrology, Mongolian Academy of Sciences, Geography Institute Laboratory and field measurements of hydroclimatic, geochemical and geomorphological parameters Statistical analyses of hydro(geo)logical and environmental data Development of basin-scale, predictive hydrological models: -distributed (GIS-based) modelling -sediment transport models (HEC-RAS) Methods

4. Background: Russia Permafrost area, ultimately drains into the Arctic Sea Essentially unregulated Unique ecosystems in Lake Baikal and the Selenga River delta Pollution and sediment transport in the Selenga river Basin -Heavy metals from mining -Nutrients from agriculture

5. Objectives Confront multi-method field investigations in Baikal Basin with multi-model quantification approaches to investigate fundamental research questions on the transport of substances through large drainage basins and impacts of human activities.

6. How much will contaminant sources 1 & 2 contribute to coastal pollution… … if degradation occurs at the same rate in both cases? Surface water divide Coastline Coastal water Diffuse SGD into the sea River basin Contaminant Source 1 Stream network Streamflow into the sea Contaminant Source 2 From source to recipient: Example flowpaths and transport times Slow flow through groundwater Fast flow through stream

7. Method: Destouni, G., Persson, K., Prieto, C. and Jarsjö, J., 2010. General quantification of catchment-scale nutrient and pollutant transport through the subsurface to surface and coastal waters. Environmental Science & Technology, 44(6), 2048–2055 Application: Khadka, S., 2010. Catchment-scale transport through groundwater to surface waters of the Lake Baikal drainage basin, MSc thesis, Stockholm Univ. Mass delivery fraction: The fraction of mass released at a location that reaches the recipient......for a given flow field and degradation rate,. Mass delivery fraction:

8. Heavy metals spread in dissolved form and with sediments  Estimate total mass flows – and its variance – along the river network (+erosion,deposition/accumulation)

9. Heavy metal loads (Zaamar): Tuul – Orkhon - Selenga ’Placer mining’ – alluvial sediments (river bank) Increases sediment and pollutant transport Measurement locations for C and Q Zaamar Goldfields: Placer mining along Tuul river

10. Estimated mass flows of heavy metals From: Thorslund, J., Jarsjö, J., Chalov, S.R., and Belozerova, E.V., 2012. Gold mining impact on riverine heavy metal transport in a sparsely monitored region: the upper Lake Baikal Basin case. Journal of Environmental Monitoring, 14, 2780–2792

11. Main findings Mining increases natural transport of dissolved heavy metals by an order of magnitude. Transport in suspended phase much higher than the dissolved one The suspended phase transport increased by 1-2 orders of magnitude during a single rainfall event  Mass flows may be underestimated if sampling is infrequent Hypothesis: High pollution transport in suspension and lower downstream pH can contribute downstream dissolution, explaining why dissolved concentrations are higher farther away from the mining site than on it Critical question: How long distances can sediments from the mining site be transported?

12. Increased sediment discharge where channel slopes are steep (as in the Zaamar Goldfield) Modelled sediment discharge Sediment discharge (tons/day) Distance along river (km) After: Pietron, J., 2012. Modeling sediment transport in the downstream Tuul River, Mongolia, MSc thesis NKA 61, Stockholm Univ.

13. Modelled sediment discharge Sediment deposition (fine particles) just downstream of the Zaamar Goldfield Sediment discharge (tons/day) Distance along river (km) After: Pietron, J., 2012. Modeling sediment transport in the downstream Tuul River, Mongolia, MSc thesis NKA 61, Stockholm Univ.

14. Main findings Under normal hydrologic conditions, most of the material released by mines is deposited within the first kilometres downstream of the mining area During peak flow events, the contaminated sediment may be transported further downstream the reach. Consequently, the mining waste sediment can contribute to sediment loads leaving the Tuul River system. Higlights the importance of extreme events on overall transport

15. Future work, plans and possibilities Local transport processes: hydrochemical conditions in different connected water systems: waste ponds, groundwater, channels, river water, suspended material, river sediments Phase transformation processes: equilibrium and/or non-equilibrium Presense of geochemical gradients on different scales (local-regional)? Implications of local processes for large-scale transport? Projected future chages: Impact of land use change, water use change and climate change (e.g., methods from parallel work in the Aral Sea basin): average conditions, peak flows, contaminant transport

16. Publications Chalov SR, Zavadsky AS, Belozerova EV, Bulacheva MP, Jarsjö J, Thorslund J, Yamkhin J., 2012. Suspended and dissolved matter fluxes in the upper Selenga river basin. Geography Environment Sustainability 5(2): 78-94 Thorslund J, Jarsjö J, Chalov SR, Belozerova EV, 2012. Gold mining impact on riverine heavy metal transport in a sparsely monitored region: the upper Lake Baikal Basin case. Journal of Environmental Monitoring, doi: 10.1039/c2em30643c Pietron, J., 2012. Modeling sediment transport in the downstream Tuul River, Mongolia, MSc thesis NKA 61, Stockholm Univ Khadka, S., 2010. Catchment-scale transport through groundwater to surface waters of the Lake Baikal drainage basin, MSc thesis, Stockholm Univ. Jarsjö, J., Asokan, S.M., Prieto, C., Bring, A. and Destouni, G., 2012. Hydrological responses to climate change conditioned by historic alterations of land-use and water- use. Hydrology and Earth System Sciences, 16, 1335–1347. Destouni, G., Persson, K., Prieto, C. and Jarsjö, J., 2010. General quantification of catchment-scale nutrient and pollutant transport through the subsurface to surface and coastal waters. Environmental Science & Technology, 44(6), 2048–2055 Internat. Journal papers (Selenga -Baikal) MSc theses (Selenga -Baikal) Internat. Journal papers (Analysis methods)