Olive mill waste water has both a high Biological Oxygen Demand (BOD) and a high Chemical Oxygen Demand (COD). These factors, along with the presence of phytochemical ingredients of the waste will, as ststed earlier, cause a reduction in the microflora of the surroundings.

My small press produces a small amount of such waste, and it kills the grass where it is discharged.

There is plentry of info about the composition and treatment of mill waste waters, Google is your friend in these things. use "OMWW", "Olive waste water", "olive waste treatment" as seeds for the search.

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