Hydrocarbonsoil

Hydrocarbonsoil is soil containing notable concentrations of hydrocarbon compounds, typically petroleum-derived. It may form from natural hydrocarbon seeps or from human activities such as oil extraction, refining, storage, transportation, and industrial use. The term covers a broad range of contamination levels from trace residues to heavily polluted zones.

Chemical composition varies but commonly includes aliphatic and aromatic hydrocarbons, including total petroleum hydrocarbons (TPH) and polycyclic aromatic hydrocarbons (PAHs). Hydrocarbons tend to sorb to soil organic matter, are often hydrophobic, and can reduce soil porosity and aeration, affecting microbial activity and plant growth. Volatile fractions may dissipate over time, while heavier fractions persist for years.

Occurrence and impact: Hydrocarbonsoil is found near oil fields, refineries, pipelines, tanker routes, landfills receiving oily wastes, and in spill sites. Persistent contamination poses risks to groundwater through leaching, affects soil biota, and can accumulate in crops. Risk depends on hydrocarbon type, concentration, depth, and soil properties.

Assessment: Evaluation involves sampling soil at depth, laboratory analysis by GC-MS or GC-FID to quantify TPH and PAHs, and risk assessment using concentration-based benchmarks and fate-transport models.

Remediation: Approaches include natural attenuation for low-load areas, bioremediation using hydrocarbon-degrading bacteria, biostimulation and bioaugmentation, phytoremediation, and physical methods such as soil excavation, washing, and thermal desorption or in-situ oxidation. Choice depends on contamination level, depth, and land use.

Regulatory frameworks: Standards for hydrocarbonsoil are set by environmental agencies and vary by jurisdiction, with common metrics including TPH, PAHs, benzene, toluene, ethylbenzene, and xylene limits. Monitoring and cleanup goals aim to protect soil function and water quality.