This report consists of lab scale experiments and amendment studies of biosolids from Mangere Wastewater Treatment Plant, Auckland New Zealand. The physiochemical parameters of interest in this study were lipids, proteins, carbohydrates, total carbon (TC), inorganic carbon (IC), pH and dry solid contents.In the first stage, this study was carried out to develop protocols for the accurate assessment of the selected physiochemical parameter in biosolids then; this study was further extended by planning various sets of experimental runs to study the temporal trends in biosolids. In one set of experiments, biosolid amendment was carried out with different concentrations of lime. In other set of experiments biosolid was amended with fixed amount of lime and different concentration of fly ash. Both of the amendments were made on the basis of percentage of the dry weight of the biosolid. In this study, the data for the selected physiochemical parameters was recorded at Day-1, Day-8 and Day-56. The results were plotted independently for tested parameters showing temporal changes with different incubation time in microcosms studies.