Silageproduction has been increasing to cover the demand from intensivelivestock production. Volume of silage used has risen (over 6tons/cow/year) and the period of use of silage feed is now longer(silage can be used all year round).
Silagejuice accompanying silage production is a very dangerous waste. Acidicwaste (pH 4.2-4.9), large content of organic compounds (85-90% in drymass), large contamination load, and high toxicity of silage juices arethe main problems. BOD5, biochemical oxygen demand (theamount of dissolved oxygen needed by aerobic biological organisms in abody of water to break down organic material present in a given water orwaste sample at certain temperature over a specific time period, in thepresence of viable bacteria and extracellular enzymes) of silage juicescan be as high as 90,000 mg O2/L. For comparison, BOD5 of pig excreta is 35,000, cattle slurry - 15,000, and household waste - 0.500O2/L.High concentration of livestock production carries the risk of surfaceand ground water contamination, and the resulting contamination of waterwells which cannot be used for consumption, or even for technologicalpurposes. Water contamination with silage juice can result in fishdie-off, and increased mortality and morbidity rates among younganimals, etc.
Themagnitude of risk from silage juice depends on the volume of silagejuice produced (it is the highest in the case of wet silage),leak-tightness of the fermentation process (silage preparation directlyon land, without pipe drains and leak-proof waste collection is theworst case scenario) and dilution (increased water consumption). It isestimated that professional silage tanks (silos) are present in onlyabout 10% of agricultural holdings in the Miedwie Lake catchment area (Zachodniopomorskie Province).