Simulation model for feasibility studies on bioremediation of uranium mill tailings using hyper accumulator Chrysopogon zizanioides

Abstract

Contamination of environment by uranium is expected in places where mining of uranium ore and processing, nuclear testing and reactor operations when the control measures are not effective. The daughter radionuclides of the ores, chemical additives and residual uranium are the maincomponents of processed waste from uranium industries. The bioremediation of contaminated areas using plant species or group of the plant may offer a cheap, renewable and promising approach to ensure long-term protection to the environment. In view of this, experiments were carried out to study the uranium immobilization potential of vetiver grass (Chrysopogon zizanioides (L.) Nash) under simulated conditions using the complex tailings. The vetiver plants were planted in simulation tanks at Health Physics Unit (HPU), Jaduguda, Jharkhand, India and periodic samplings were carried out to investigate the extent of uranium uptake. The acid aliquot of ashed plant samples, soil and tailings were subjected to solvent extraction followed by UV-Fluorimeter for estimation of uranium. The studies indicated that the plant species could bioremediate up to 49% of the uranium at 90th day of the experiment and the uranium remediation efficiency of vetiver increased with time and uranium was predominantly localized in the roots of the plant.