On January 28, sewage plant operator Nagano Prefecture Suwa Construction Office announced that approximately 1.9 kilograms (4.2 lbs) of gold can be mined from each ton of molten fly ash generated when incinerating sludge at its facility in the town of Suwa.
Located in central Nagano prefecture, the Suwa Basin is home to numerous precision machining companies, metal plating facilities and hot springs, which may explain the high concentration of gold in the wastewater sludge.
From the Upcoming ueue, submitted by shadowfirebird.
Geez...
Not a bad haul per tonne, but still, I think I'll stick to skipdiving thanks.