My neighbors on 2 sides are monoculture/toxic

hello, newbie forumer here.

i just bought a 5 acre property that will be turned to a permie demo farm in the philippines. my neighbors on two sides (plus one across the road) are monoculture banana farmers who use chemical farming techniques. i need advice on how to lessen toxic contamination on my side, and prevent the inevitable pest plagues from coming over to my side of the land. is this a big problem? i hope i can still make a go of being a permie there. i didn't consider my neighbor's properties before i bought. otherwise i just blew a huge part of my seedcorn. the one above me particularly bothers me as they are upslope of us and we're in a mountain slope. any water i get from runoff most likely will be contaminated. so retention ponds might be out of the question.

my ideas (don't know if advisable): build high hugelkultur beds as barriers, plant lots of high shrubbery and leafy trees to block off chemical sprays, put lots of chemical eating mycela/mushrooms in strategic places, etc.

thanks for any advice or personal experiences!!

mauiboi