Geochemistry of shoreline sites impacted by submarine groundwater discharge in Hel, Puck Bay, Poland, southern Baltic Sea 2009 and 2010

Pore waters were retrived from coastal sands of the southern coastline off Hel Island, Puck Bay, southern Baltic Sea. Multiport-porewater lances equipped with syringes were used to obtained vertical profiles in areas impacted by fresh submarine groundwater discharge and less impacted 'reference sites'. Samples were taken during 11 campaigns between September 2009 and October 2010. Pore waters were analyzed on-site for salinity and pH, and for major and trace elements, water isotopes (H,O) and the C isotope composition of dissolved inorganc carbon in the laboratory (via ICP-OES and gas mass spectrometry). Selected methane samples were analyzed via GCirmMS for the C and H isotope composition. It was the aim to investigate the fluxes and fresh water composition of submarine groundwater discharge and the seasonal dynamics.