Engineering Solutions for Environmental Remediation, Techniques for Heavy Metal and Organic Pollutants

Abstract

Environmental contamination by heavy metals and organic pollutants represents a persistent and complex challenge for engineers due to their toxicity, mobility, and long-term ecological impacts. Industrial discharge, mining activities, agricultural runoff, and improper waste disposal have led to widespread soil and water pollution that threatens human health and environmental sustainability. This review critically examines engineering-based remediation strategies developed to address heavy metal and organic pollutant contamination across terrestrial and aquatic systems. Emphasis is placed on physicochemical remediation technologies, engineered biological systems, hybrid treatment processes, and emerging remediation frameworks designed for field-scale deployment. Techniques such as soil washing, chemical stabilization, electrokinetic remediation, permeable reactive barriers, advanced oxidation processes, and engineered bioreactors are discussed with respect to design principles, efficiency, and limitations. The paper also evaluates recent advances in nanotechnology-assisted remediation and integrated remediation systems. Challenges related to cost, scalability, site heterogeneity, and regulatory compliance are analyzed. The review concludes by identifying future research directions necessary for developing resilient, adaptive, and sustainable remediation systems capable of addressing complex contaminant mixtures.