Assessment of Heavy Metals Accumulation Hazard in Estuarine Ecosystems During Polymetallic Ore Mining on Arctic Islands

The condition of river mouths of Vaygach Island (Nenets Autonomous Area), in particular the Krasnaya River, where in the first half of the last century lead-zinc ores were mined without observing nature protection measures and reclamation after the mine conservation. It was revealed that in the mouth of this river there is an accumulation of heavy metals in bottom sediments and aquatic vegetation. Lead content in algae was found to be 4.8 times higher than the sanitary norm. It is recommended that wastewater from mines should be discharged to deep sea areas with salinity over 20 ‰ or discharged into drainless thermokarst lakes, which have no ichthyofauna and freeze to the bottom in winter.