Investigations for Soil Contamination with Hydrocarbon Compounds near Oil Stations

Field companies are subject to many standards to preserve the environment. Oil companies are considered among the companies that cause the most environmental pollution for two reasons: the first is the extraction of large quantities of crude oil, and the second is their violation of the controls imposed on them. In this research the investigations on the nearby and around a Rumaila oil station area were abducted scientifically through a real tested sample. In this research, investigations in an area near and around the Rumaila Oil Station were conducted scientifically through real laboratory samples. An analysis was made to determine the total petroleum hydrocarbons (TPH), where 22 samples were collected, as well as 5 laboratory samples of soil from an unpolluted area, and crude oil was added to it in known proportions to determine the spectral signature. The ASD Field spec 3 device was used to record the spectral signatures of each sample. Areas sensitive to hydrocarbons 17050 and 1350 appeared. The results show a variation in the concentrations of hydrocarbon in the samples from (2 ppm) at the minimum and reach (197 ppm) at other locations around the station.


Introduction
Soil is exposed to many pollutants as a result of natural conditions and fluctuations during the seasons, climate changes and earthquakes.This increases compounds and elements and sometimes poses a threat to the lives of living organisms by increasing toxic substances.It is necessary to have continuous examination to follow up on natural changes to avoid danger.As for soil pollutants that occur due to human influence Due to daily activities or factory waste without the supervision of competent authorities, controls must be put in place to work with, with penalties and fines for violators.[1][2][3][4][5] In the context of this study, we examine hydrocarbon pollution, which is considered one of the most dangerous pollutants and has the most impact on people's lives, because they are in daily contact with it and are used in fuel for transportation, electricity, and other supplies.Economic and life aspects.[6][7][8][9][10] , Because TMREES-2023 Journal of Physics: Conference Series 2754 (2024) 012025 IOP Publishing doi:10.1088/1742-6596/2754/1/012025 2 the marshes are one of the most important natural and heritage landmarks in the world, the soil of the marshes is affected by seasonal drying and continuous sedimentation processes, as its content is high in organic materials from plant and animal wastes and microorganisms, and due to the climatic effects of the region, compounds rich in the elements hydrogen, phosphorus, oxygen, carbon, and others are excreted in the soil, but due to the factors of erosion and drought.To which you are exposed, the values of mineral substances decrease and pollutants increase.[11][12][13][14][15] Hydrocarbon pollution is a major environmental concern that can have serious consequences for human health and the ecosystem.Hydrocarbons are organic compounds that are composed of hydrogen and carbon atoms.They are found in crude oil, gasoline, diesel fuel, and other petroleum products.[16][17][18][19] The fusel fuel is one of the most important sources of energy.It is necessary to monitor and treat cases of pollution that occur due to natural causes, such as changing the shape of the land, such as continental drift, the movement of rocks, and earthquakes.Which lead to natural oil leaks, spills and explosions in oil pipelines and tankers, and oil production plants also constitute the most dangerous causes of hydrocarbon pollution.[20][21][22][23][24][25] Hyperspectral imaging is a powerful tool for detecting and mapping hydrocarbon pollution.The detection strategy depends on the type of oil, light or heavy, recently or formerly spilled, and on the substrate, various processing methods can be used to detect hydrocarbon-bearing materials, such as spectral index calculations, anomaly detection, and spectral unmixing 1. Anomaly detection methods are interesting for detecting hydrocarbons whose spectral signatures have no or poorly detectable specific spectral characteristics.However, they can also be used in combination with spectral index calculation to reduce the number of false alarms.[26][27][28][29][30] To detect hydrocarbon contamination using spectral fingerprinting, which is infrared spectroscopy.It can be used to identify and measure amount of hydrocarbons in a sample.This technique works by measuring the infrared absorption of hydrocarbons in the sample.You can use a technique called gas chromatography-mass spectrometry.GC is a powerful analytical technique that can detect and identify hydrocarbons in complex mixtures.It is a two-step process that involves separating hydrocarbons using gas chromatography and then identifying them using mass spectrometry.[31][32][33][34][35] The most important method used to detect hydrocarbon pollution is spectroscopic analysis, because when hydrocarbons are present in soil or water, they give distinctive spectral fingerprint.[36][37][38][39][40] Spectral imaging, which constitutes hyperspectral remote sensing techniques (HRS), can be used to detect the spectral absorption and reflection features of contaminated samples due to the chemical and physical properties of the materials.The use of these methods in studies has given excellent results in demonstrating and determining the percentage of hydrocarbon contamination [41][42][43][44][45] The reason for the occurrence of natural oil leaks and the damage to living organisms was that it was necessary to use methods that help detect pollution.Two sets of samples were used in Brazil by Scafutto et.al.[46].The first set was the contaminant sample and mineral substrates.The Field Spec 3 Hi Res device was used to take spectral predictions of the samples that was measured.The reflectivity properties of near and short infrared rays have proven the ability to distinguish absorption features, type and density of hydrocarbons and are considered a reliable source for monitoring fuel and oil leaks.Due to the large presence of pollutants in the soil of Diyala Governorate in Iraq and their risks to environmental life and living organisms, Muhammad et.al.[47] have the lead to take 5 soil samples at the studied area.The researchers were managing the samples through compressed, sorted and prepared to calculate the concentration of heavy elements through spectroscopy using an X-ray EDX device.The results have proven effective in detecting the heavy elements present in each sample.[48] Basra, in southern Iraq, is exposed to many pollutants in soil components and heavy metals.12 samples were taken in the Al-Zubair area for chemical analysis.QGIS and ENVI programs were also used for their effectiveness in determining the presence of polluting compounds and their concentrations.[49] Due to the seriousness of petroleum pollutants and their effects on living organisms, field samples were taken in Israel to detect total hydrocarbon pollution (TPH) through spectroscopic analysis of five types of soil using near and short infrared (400-2500 nm) due to its effectiveness and high accuracy.[50] Spectral analysis was used using the Field spec 3 device, the ISG program for spectral geology, and ASTER satellite data to collect 45 soil samples from 20 sites in the Maroun, Mansouri, and Kohistan oil fields.The results of hydrocarbon pollution indicated that it is linked to certain metals.

Study area
Pollution increases in areas close to the sources of pollution due to the exposure of the donkey marsh to hydrocarbon pollution as a result of the accumulation of pollutants from nearby oil fields, where the North Rumaila field is located at the coordinates from 47° 16 '

Materials and Methods
The application of remote sensing techniques and spectral signatures has gained great interest in identifying soil pollutants, especially hydrocarbon pollution, to characterize the reflected spectrum.

Soil Sample Preparation
Field work was carried out on 10/24/2023 in the study area in the North Rumaila field in Basra Governorate, Iraq.The soil in this area is sandy and contains fluvial deposits from swamps.It is also part of the alluvial plain, as it consists of organic materials, salts, carbonates, and many others.Among the chemical components, the presence of an oil field in the area adds a serious impact on the soil and increases the percentage of pollutants.Therefore, soil samples were taken in different areas over an area of 126 square kilometers, and 22 samples of soil contaminated with hydrocarbons were collected in the locations shown in (Table 1).To determine the location, use Google Earth.

Spectroscopy Reflection
Use the ASD Field spec 3 device, model 2010, which is a full-range radiation spectrometer and gives the fastest and most accurate measurements in the portable spectral field in the field to obtain reflection spectra for each sample in visible-near infrared VNIR and short wave infrared SWIR reflection spectral, within the spectral range of 400 Nanometer to 2500 nanometer, and it consists of the main device, and connected to it is a small hand-held device that contains a light source to assist in taking the spectral fingerprint and is in contact with the sample.Technicians use a stone with it to zero or equalize the device before taking the spectral fingerprint for each sample, as it is connected to a computer to display Results: A special program,View spec Pro, is used for this.The samples were placed in boxes and their spectral fingerprint was taken for each soil sample to determine the reflectivity in the presence of hydrocarbons.

Gas Chromatography-Mass (GC-MS)
Shimadzu Model 2010 Gas Chromatography Gas chromatography-mass spectrometry (GC-MS) is a technique for the separation and detection of molecules.It is a method used in various industries such as environmental analysis and petrochemicals to detect organic molecules or gases.
Only, as it consists of three parts: 1-The oven with the coulomb inside it 2-Injector 3-Detector 4-The device contains three analysis programs for the convection oven, a thermal program for the injector, and a thermal program for the detector.5-In addition, the gas samples contain bottles or a gas generator.

Results and Discussion
The reflectivity value of hydrocarbons appears in the spectral range 17050 and 1350, which is sensitive to hydrocarbons in soil samples obtained from spectroscopic analysis of field specifications 3 There is a high percentage of crude oil coordination with the percentage according to the World Health Organization WHO, which is 10 micrometers per liter.
The work was divided into two groups, the first of which includes 22 samples from oil soil adjacent to North Rumaila oil and well oil production plants, while the second category includes laboratoryprepared samples of crude oil and sandy soil free of oil and linked to certain known proportions.
The areas that show sensitivity to hydrocarbons are 17050 and 1350, while the soil that is not contaminated with blue does not show any spectral sensitivity because it is free of hydrocarbons.The places that show dips in the chart, which are considered general in all soil spectrograms, are 1400, 1900, and 2200, which represent water absorption sites or areas of moisture.
Other than that, they are direct spectral indicators where the soil is mixed with crude oil, and the difference in concentrations is perfectly clear through the difference in reflectance between 0.25-0.05microns as shown in the figure 7. The sample in reflectivity in blue at the bottom was taken from an area near an oil pond and the soil sample has black color.Because of this, it has high absorption and lower reflectivity,While the reflectivity of the sample in black at the top is pure soil free of crude oil and it is from an unpolluted area.The rest of the samples show different reflectivities depending on the presence of hydrocarbons that affect the near and short infrared region in the spectral range 1700 to 2300 nanometers.As shown in the figure 8 .The results obtained from the GC device are the concentrations of hydrocarbon compounds for each sample, and the location and concentration of each sample are indicated in the table 3 The results showed a discrepancy in the presence of compounds, and this discrepancy results from the extent of contamination of the surface soil near the Rumaila field due to waste or due to wells in the area near the Hamar marsh.Likewise, in samples F17 and F22 from the same location near an oil pool, F17 was yellow in color and had a hydrocarbon percentage of (146.8524128ppm), while F22 was black with a hydrocarbon percentage of (34.33922597 ppm).While the highest percentage of hydrocarbons (332.5407125ppm) was recorded at site F3, which had clay soil.As for the result of the sample on the edge of the Al-Hammar Marsh, adjacent to the Ironing Bridge -F21 Bridge, the percentage was (197.7750901ppm), which is a very high percentage of hydrocarbons, as the area was abandoned.

Conclusion
One of the most important techniques used in detecting hydrocarbon pollution is spectroscopy using an ASD Field Spec 3 device and gas chromatography GC.The absorption regions of hydrocarbon compounds in the range of 1750 to 1350 nanometres were displayed using an ASD Field Spec 3 spectrometer, and the results were displayed in the View Spec Pro program to produce High-accuracy charts for analysing samples and exploring hydrocarbon reflection areas, as it is considered one of the most important remote sensing techniques in detecting pollutants.The accuracy of the results is ensured by chemical analysis, extracting the percentage of hydrocarbons in each sample, and clarifying the contaminated areas.A mount of hydrocarbons in samples F9, F12, F14, F17, and F21 recorded the highest rates of contamination.
23.271"E, 30° 42' 45.769"N to 47° 21' 55.343"E, 30° 35' 10.267"N (which is located in the southern part of Iraq, north of Basra Governorate).It contains many finds and discoveries.Undiscovered oil wells It is considered the third largest oil field in the world and soil contamination must be monitored.Worldview satellite image dated 02/18/2019 was used.With cloud cover 0% at a resolution of 60 cm and displayed using the ArcGIS program as shown in the figure1

Figure 4 . 6 Figure 5 .
Figure 4. Samples that prepared at laboratory with different contaminated percentage by oil

Figure 7 .
Figure 7. Spectral reflectivity of crude oil in soil using ASD field spec3 for the prepared laboratory samples with oil amount (5, 10, 15, 20) ml.

Figure 8 .
Figure 8. Spectral reflectivity of field samples using ASD field spec3

Table 1 .
Locations of Samples of soil with coordinates Figure 3. Site field work for collecting the samples 3.2.Laboratory sample This stage of work was carried out on five samples.The experiment was conducted in the laboratories of the Environmental Research Center, where sand was used from an area close to the study area at 30 38 47 North, 47 30 48 East, and different amounts of crude oil were added to each.500grams of soil according to Table2.

Table 2 .
Prepared the Laboratory Sample with different percentage of oil

Table 3 .
Hydrocarbon Concentration (ppm) in sampleIt was found through the concentration of hydrocarbons that the concentrations of hydrocarbons are different, as in the sample F 4 and F 5 from the same location, but the results are different, as the percentage of hydrocarbons in F4 (2.02686736 ppm) while in F5 (20.33465417 ppm) and the soil was moist in this area and close to oil pipelines.