Filtering out excess Nitrogen with Biochar

In many areas, you can't drink your well water, because they've been adding synthetic nitrogen fertilizers, that aren't mostly soaked up by the lack of organic material.  It goes into the water table.  This paper talks about a method to make biochar with iron to filter it out:
John S
PDX OR

https://link.springer.com/epdf/10.1007/s42773-025-00516-5?sharing_token=WgulsZOnS7w33XLPZwigqPe4RwlQNchNByi7wbcMAY6r2grbVa9pygSUhu5QRBxumO76vymTJcFJjVoj0yaVOUlRpQOYAlnlzmXk6-bjY-fu0w5ZUkzjMYgtz0E7TzbTV_GOoPTClLMvU7BR1UZ2paKHIen6NOPGN8tWPOg0U_k%3D

I'm hoping this could help folks in Eastern OR who have this problem, its bad in certain areas over there, lots of tainted wells.  

I remember going through Central California's valleys.  Forest Service people told me not to drink the tap water 35 years ago, because so much of the synthetic fertilizers and pesticides had permeated the water table. They all drank bottled water then.  Yes, there were tons of plastic bottles strewn about that county.

John S
PDX OR

Encouraging, but the process looks like it requires inputs that most of us don't have. Enhanced biochars are a fascinating topic and I have a low-tech method of making magnetic biochar by treating feedstock with rust and oxalic acid. Hopefully I can get it tested soon to see how it performs (lab work is $$).