Salt can also be obtained by solar evaporation, in which seawater (or briny lake water) is pumped into a series of large, shallow ponds and left to evaporate naturally. The process is very slow—it can take years—but it requires very little fossil-fuel input. With large-scale operations, wildlife issues may come into play, while ponds can provide sanctuary for certain wetland species, like flamingos and other birds. The liquid that remains after the solar evaporation process—known as bitterns— in large, concentrated amounts can be harmful to fish and other aquatic organisms. Washing and refining can be as energy-intensive as vacuum pan refining. But most gourmet sea salts are harvested from the evaporation ponds—sometimes with hand tools—and then treated very minimally before they’re packaged and sold. Friend of the Sea has developed Sustainable Sea Salt standards and it is in the process of developing standards for Sustainable Salt from solution mining.