The Baltic-one of the most polluted waters on Earth is in fact a treasure trove of easy-to -retrieve minerals, metals and composting material. If you remove the sediment that contains the legacy of hundreds of years of latrine and chemical farming you restore the waters and get pristine raw materials.
The restauration of the Baltic would be a gigantic win for the circular economy. It might require a shift. Either we pay little for our food and sewage and a lot (via taxes) for restoration or we pay more for food and sewage and much less to restore our nature.