FTIR was carried out in control soil, polluted soil and remediated soil with plant material-L. leucocephala biomass. A comparison done between the spectral reflectance of the control soil, dye contaminated soil, and remediated soil showed the following results. A peak was observed at 3394–3363 cm−1 corresponding to amines (N–H) in the control soil and remediated soil but absent in polluted soil. Similarly the presence of carboxylic acid at a peak of 2515–2430 cm−1 was missing in the polluted soil and present in the control and remediated soils.