Introduction

This page gives an indication of the pollution groups present in the modern regulations of the SIKB and a description of every group. Soil pollution as part of land degradation is caused by the presence of human-made chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals or improper disposal of waste. The most common chemicals involved are petroleum hydrocarbons, polynuclear aromatic hydrocarbons, solvents, pesticides, lead, and other heavy metals. Contamination is correlated with the degree of industrialization and intensity of chemical substance. The concern over soil contamination stems primarily from health risks, from direct contact with the contaminated soil, vapors from the contaminants, or from secondary contamination of water supplies within and underlying the soil.[1]

The defined pollution groups are the following: phenols, heavy metals, oil, PAK's, radiation, fibres, volatile hydrocarbons, volatile chloridehydrocarbons and germs.

Phenols

In organic chemistry, phenols, sometimes phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (—OH) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, C₆H₅OH. Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the molecule. Chemical structure of salicylic acid, the active metabolite of aspirin. Phenols are both synthesized industrially and produced by plants and microorganisms.

Metals

Chromium, Mercury, Arsenic, Lead, Nickel, Cadmium, Copper, Zinc, Manganese, Selenium, Silver, Tin, Thallium Cobalt and Vanadium are the heavy metals that can be present in the subsurface. These heavy metals are very dangerous for the environment and most of them can be transported via the groundwater. The amount of these metals in the subsoil shouldn't transcend the local geochemical baseline concentrations. (GBCs)

Heavy metals can degrade air, water, and soil quality, and subsequently cause health issues in plants, animals, and people, when they become concentrated as a result of industrial activities. Common sources of heavy metals in this context include mining and industrial wastes; vehicle emissions; lead-acid batteries; fertilizers; paints; and treated timber; aging water supply infrastructure; and microplastics floating in the world's oceans.

Oils

There are three types of polluting oil that can be present in the subsoil. All types and their description can be found below.

Refined oil

Refined oil can consist of several flows. Refined oil is mineral or synthetic lubricating oil, industrial oil or is mixture of those which has become unfit for usage. Refined oil is defined as halogen containing if the amount of halogen present is greater than 1000 mg/kg.

Drilling and oil platforms

Drilling and oil platforms are dismantled on land after the operational phase. The entire drilling and oil platform is considered to be hazardous waste, due to the presence of oil, asbestos and other hazardous substances. Only on land the hazardous waste materials can be safely disposed of.

Mineral oils

Mineral oil is in general oil that is made from petroleum in contrary to oil with an animal- or plant-based origin. For the production of different types of mineral oil, petroleum is distilled and produces fractions consisting of different mixtures of hydrocarbons with different boiling points. As a rule a distinction is made between the following fractions:

1. Gasoline (gasoline)
2. Diesel / fuel oil
3. Heavier fuel oil
4. Crude oil

Soil polluted with mineral oil (>1000 mg/kg) is considered as dangerous waste when the amount of benzene present in the oil is greater than 0.1 mass percentage or when it is fuel oil. (>1000 mg/kg) Only when speaking of diesel there is a limit of 10.000 mg/kg.

PAH

Polycyclic aromatic hydrocarbons (PAHs) are substances created when organic materials such as wood, food, tobacco and fossil fuels are not burned completely. There are hundreds of different PAHs, with different properties. Plants can absorb some PAHs from the soil; thus, through food crops, they can end up in our bodies. Other PAHs are not absorbed by plants, and enter the body only when soil particles are eaten

All the different types of PAHs need to be considered differently and they have different exceedance values. PAHs are found in the ambient air in gas-phase and as sorbet to aerosols. Atmospheric partitioning of PAH compounds between the particulate and the gaseous phases strongly influences their fate and transport in the atmosphere and the way they enter into the human body. The removal of PAHs from the atmosphere by dry and wet deposition processes are strongly influenced by their gas/particle partitioning. Atmospheric deposition is a major source for PAHs in soil. [3]

Radioactive material/radiation

Fibers/Asbestos

Asbestos has a presence limit of 0.1%.(1000 mg/kg)

Volatile hydrocarbons (VOCL)

Germs (Anthrax etc)

References

• Risk Assessment Guidance for Superfund, Human Health Evaluation Manual, Office of Emergency and Remedial Response, U.S. Environmental Protection Agency, Washington D.C.
• Jiang, HH., Cai, LM., Wen, HH. et al. Characterizing pollution and source identification of heavy metals in soils using geochemical baseline and PMF approach. Sci Rep 10, 6460 (2020).
• Hussein I. Abdel-Shafy, Mona S.M. Mansour, A review on polycyclic aromatic hydrocarbons: Source, environmental impact, effect on human health and remediation, Egyptian Journal of Petroleum, Volume 25, Issue 1, 2016,Pages 107-123.