This study proposed a two-phase mechanism of phenol degradation in wastewater by vetiver grass. Phase I is phytopolymerization and phytooxidation assisted by root- produced H2O2 and POD, while Phase II is a combination of Phase I with enhanced rhizomicrobial degradation. This study also evaluated the feasibility of phenol degradation on a laboratory scale using vetiver grass in a floating platform and PRVRB. Phenol was degraded at rate constants of 9.7x10-3 h-1for vetiver grass in a floating platform (100 plants per 35 L of wastewater) and 10x10-3 h-1for the PRVRB (20 plants over a length and width of 40 and 20 cm, respectively). Although these phenol degradation rates are around 10 times slower than those achieved with advanced engineering techniques, such as ultrasound (phenol degradation rate =111 x 10-3 h-1), the phytoremediation of phenol and other hazardous substances at Nong-Nea village by vetiver grass is much more suitable when considering the practicality of the technique and the widespread nature of the contamination. Advanced engineering techniques are suitable for source zone treatment, but are mostly economically unpractical for widespread contaminants.