Well purity grinding

[Procne]

When you plant a field near a well then every piece of humus or fertilizer you use on the field adds to the well's alchemical composition. The humus / fertilizer gets absorbed into soil and then reaches groundwater. With fertilizer normal diminishing returns are applied.

When you plant a tree near a well then during its growth it takes away from well's alchemical composition. Tree's roots absorb elements from the soil.

So if you plant a field and use salt humus / fertilizer then well's water will be more salty. If you plant salt tree then well's water is less salty. Effect is balanced in such a way that both fields and trees contribute to the half of well's alchemical composition.
So if you want 100% salty water then you will need to use (100,0,0,0) humus / fertilizer on fields and plant (0,33,33,33) trees.

Effect is limited to the 4 nearest fields and 8 nearest trees.