Biochar filters for soil and river cleanup
A friend of mine has a biochar system under his Sustainable People's Project which won some accolades some years back. He basically put a series of biochar filters across the river which fed into his farm and village from a mining district to filter out toxins and oils which were leached out. He used hesian sacks sewn into tubes filled with vast amounts of biochar and strung them across the top of the water ways. I think the toxins were somehow floating on top, trapped in the oil or something but it did a lot of good to the river health.
He's since experimented with removable biochar filter in swales to filter toxins being leached across soils.
Has anyone else tried biochar methods like this? Any success?