Assessing the changes in soil properties and possible ground water pollution with application of primary treated distillery spentwash

To assess the ground water pollution with varied amounts of primary treated distillery spentwash (DSW) application, locally prepared piezometer were installed in the field at various depths (0.5, 1.0 and 1.5 m) and the collected leachate was characterized. Leachate was collected in piezometers upto 0.5 m depth with lower levels of DSW application (<750 m³ha⁻¹) and upto 1.0 m depth with >750 m³ha⁻¹ after 30 days of DSW application and indicated that increasing quantities of DSW application increased the pH, EC, COD, NO₃⁻, HCO₃⁻, Cl⁻, Ca²⁺, Mg²⁺ and Na⁺ contents in leachate. Leachate collected in piezometers after 60 days of DSW application showed increased leaching of NO₃⁻, HCO₃⁻, Cl⁻and Na⁺ with increasing depth, while leaching of Ca²⁺and Mg²⁺ decreased with depth. Chemical oxygen demand of percolating water decreased with increasing depth of soil column. However, application of DSW @ 1500 m³ha⁻¹ increased all the parameters in leachate indicating its possible contamination over the period to underground water. Further, the effect of percolating DSW on soil was studied by opening the soil vertical profile upto 120 cm depth. The soil reaction and soluble salt content increased with soil depth upto 90 cm and with increased rate of DSW application. Organic carbon, Available primary nutrients viz., N, P₂O₅, K₂O, Exchangeable Ca, Mg and Na and DTPA micronutrient content (Fe, Zn, Mn and Cu) increased in surface soil (upto 30 cm) with increased rate of DSW application and while sub surface soil (60–120 cm) content showed insignificant variation. organic carbon in soil surface increased with increasing quantity of DSW application. The spentwash application at the rate below 750 m³ha⁻¹ increased soil nutrient content with lower percolating leachate indicating its beneficial use for agriculturepurpose. However, theapplication rateof1500 m³ha⁻¹ maycausedetrimentaleffecton surfacesoilelectrochemical properties and percolating leachate may cause contamination of underground water under higher water table condition.