This research explores the chemical characteristics of residual pesticides present in HDPE containers and develops an optimized treatment method for their safe disposal. Organophosphate pesticide residues were analyzed using GC-MS and FTIR techniques. Adsorption and desorption mechanisms on polymer surfaces were studied using Langmuir isotherms. Alkaline hydrolysis combined with Fenton oxidation was evaluated for degradation efficiency, and kinetic parameters were determined. Results demonstrate that this combined treatment reduces pesticide residues up to 96%, allowing environmentally safe recycling of HDPE containers.