Underground Fuel Storage Tanks Research Articles

Formation potential of disinfection byproducts during chlorination of petroleum hydrocarbon-contaminated drinking water

Recent leaks of underground fuel storage tanks in the Pearl Harbor region have led to direct release of un-weathered petroleum hydrocarbons (PHCs) into drinking water sources, which then directly underwent chlorination disinfection treatment. Since the control of disinfection byproducts (DBPs) traditionally focuses natural organic matters (NOM) from source water and little is known about the interactions between free chlorine and un-weathered PHCs, laboratory chlorination experiments in batch reactors were conducted to determine the formation potential of DBPs during chlorination of PHC-contaminated drinking water. Quantitative analysis of regulated DBPs showed that significant quantities of THM4 (average 3,498 μg/L) and HAA5 (average 355.4 μg/L) compounds were formed as the result of chlorination of un-weathered PHCs. Amongst the regulated DBPs, THM4, which were comprised primarily of chloroform and bromodichloromethane, were more abundant than HAA5. Numerous unregulated DBPs and a large diversity of unidentified potentially halogenated organic compounds were also produced, with the most abundant being 1,1-dichloroacetone, 1,2-dibromo-3-chloropropane, chloropicrin, dichloroacetonitrile, and trichloracetonitrile. Together, the results demonstrated the DBP formation potential when PHC-contaminated water undergoes chlorination treatment. Further studies are needed to confirm the regulated DBP production and health risks under field relevant conditions.

Environmental Assessment of Soil and Groundwater Pollution by BTEX Leaching in Valencia Region (Spain)

The impact of hydrocarbon spills in the unsaturated zone is a significant environmental concern, particularly in locations where contamination arises from leaks in underground fuel storage tanks (USTs). This paper presents the outcomes achieved through the utilization of VLEACH, a finite-difference numerical model, to assess the concentrations of organic contaminants in the solid, liquid, and gas phases within the vadose zone. Additionally, it evaluates the mass transfer of pollutants to the aquifer as part of an environmental assessment for the placement of a forthcoming service station. The study encompasses an analysis of 18 scenarios under realistic conditions based on actual field data. These scenarios were constructed, taking into account various factors, including the nature of the leak (one-time or permanent), the depth of the phreatic level, and the soil conditions and properties. The results highlight the potential environmental consequences of a permanent leak as compared to those resulting from a specific accident. The findings further emphasize the substantial influence of soil moisture on transport phenomena within the vadose zone. Variations in soil moisture significantly alter hydraulic conductivity, impact magnitudes, transport velocities, and even the predominant transport mechanism. Consequently, precise delineation of soil moisture becomes a crucial parameter in such simulations. Additionally, it has been observed that each component of BTEX (benzene, toluene, ethylbenzene, and xylene) experiences varying transport velocities through the vadose zone. Benzene, having a greater propensity to concentrate in the liquid and gas phases, exhibits the swiftest movement through the vadose zone. The detection of benzene in aquifers can serve as an indicator of the potential future arrival of the remaining BTEX compounds.

Adsorptive Removal of Emulsified Automobile Fuel from Aqueous Solution

The development of cost-effective technologies for the treatment of water contaminated by petrochemicals is an environmental priority. This issue is of paramount importance for countries like Saudi Arabia owing to its scarce water resources. Of particular concern are automobile fuels, such as gasoline and diesel, that can contaminate water aquifers from leaking underground fuel storage tanks. Owing to the cost-effectiveness of adsorption-based technologies, low-cost high surface-area commercial activated carbon was used for the adsorptive removal of contaminants from the emulsified fuel-contaminated water. Batch equilibrium experiments showed a high efficacy of the adsorbent. Even with small amounts of the adsorbent, a removal efficiency of more than 97% was obtained for both gasoline as well as diesel. Three different well-known batch adsorption isotherm models, namely the Langmuir, Freundlich, and Temkin, were used for describing the experimental data. The best results were obtained using the Freundlich isotherm followed by the Langmuir model. The maximum capacity was found to be 8.3 g gasoline and 9.3 g diesel per gram of the adsorbent at ambient conditions for a neutral contaminated aqueous solution.

In situ thermal remediation application in South Africa: a case study incorporating sustainable remediation principles

This paper presents a case study of the first instance in South Africa where in situ thermal remediation (ISTR) was undertaken. The project, completed during 2020 and 2021, is located in Cape Town. The ‘site’ is a former printing facility located in a multistorey building adjacent to an upgradient service station. Petroleum hydrocarbon impacts, identified in subsurface soil and groundwater, originated from leaking underground fuel storage tanks at this service station. Following a sustainability-based options appraisal, ISTR with steam used as the heating source was selected as the most appropriate remedial technology. Based on Environmental Resources Management's (ERM's) international and local expertise, this solution was implemented after due consideration of the site's geological characteristics, the properties of the contaminants of concern and the client's goals of rapidly achieving a risk-based remediation solution. This solution was enhanced by the identification and incorporation, where feasible, of sustainable management practices (SMPs) in the system design and operational phases. Particular focus was placed on resource consumption and the use of alternative power sources, such as reduction of water and energy and the use of biofuel. Other SMPs incorporated into the system's operational phase included temperature tracking to optimize steam usage, which has been successfully applied by ERM at previously completed ISTR sites in other countries. Key lessons learnt from the ISTR application at this site were that the energy source and use, combined with the optimization of water consumption, could be more widely applied to improve the sustainability of ISTR, not only in South Africa but also in other sites worldwide. Supplementary material: Details of sustainable remediation assessments are available at https://doi.org/10.6084/m9.figshare.c.5965339 . Thematic collection: This article is part of the Sustainability in Engineering Geology & Hydrogeology collection available at: https://www.lyellcollection.org/cc/sustainability-in-engineering-geology-and-hydrogeology

Synthesis and chemical resistance of aluminum oxide and silicon carbide (1:1) filled Bi-Directional woven E- glass fiber reinforcement epoxy polymer composites

Fiber-reinforced polymer (FRP) composite materials have better corrosion, chemical and wear resistance, reduced weight of structure etc. due to their properties. It’s application fields include the manufacture of storage tanks for chemicals, pickling and plating tanks, underground fuel storage tanks, chimney stacks and stack liners, pulp washer drums and up-flow tubes, oil and gas carrying pipe line systems, apparatus and process equipment in power generation plants. This research work describes the development of a new set of polymer composites consisting of different weight percentages of aluminum oxide/silicon carbide (1:1) (0 wt%, 2 wt%, 4 wt%, and 6 wt%) and E-glass fiber used as a reinforced material, epoxy resin (LY 556) used as a PMC material, and epoxy resin (LY 556) and hardener (HY951) mixed in 10:1 at room temperature. The study involved four sets of composites that were fabricated using the hand layup technique. Chemical reagent (solvents and acids) absorption increased in composites with the presence of voids and an increase in the weight percentage of aluminum oxide/silicon carbide (1:1).Chemical resistant of 2 wt% composites for one day against acids (HCl, HNO3, CH3COOH), solvents (NaOH, Na2CO3), and alkalis (benzene, toluene, CCl4) gives better results and shows it can be applied in the making of storage tanks for chemicals successfully.

Fuzzy-Probabilistic Model for a Risk Assessment of Groundwater Contamination: Application to an Urban Zone in the City of Belém, Pará, Brazil

This study proposes a fuzzy-probabilistic modelling approach for groundwater contamination risk assessment (FPM-risks) regarding underground fuel storage tanks (UFST). Considering the subjective measures of hydrogeological parameters, a fuzzy inference system is proposed to assess the intrinsic vulnerability of aquifers (Y). Measurement of the UFST hazard degree (H) and natural groundwater quality (Q) is considered as a pattern framing issue, such that they were quantified by fuzzy-analytic hierarchy process (AHP) of the recognizing patterns model. Though the association among Q and the probability of using groundwater reserves (G), estimated by the Monte Carlo method, the consequences of contamination (C) were measured. Associating Y, H, and C, the basic and value-weighted risk assessment of groundwater contamination was performed in the urban zone of Belém city, Pará state, Brazil. The results showed that the majority of UFSTs concentrated in the more urbanized zone were classified by FPM-risks as high basic risk and very high value-weighted risk of groundwater contamination. Although the risk assessment should be updated regularly because of the dynamic characteristics of hazards from the USFTs, the FPM-risks was shown as a tool to be considered for managing groundwater resources, as these models overcome subjectivities and address uncertainties, thereby providing a higher level of accuracy than usual risk methods and possibly become a decision-making way.

Assessment of soil contamination caused by underground fuel leakage from selected gas stations in Riyadh, Saudi Arabia

ABSTRACTSpills and leakage from underground fuel storage tanks (UFSTs) can potentially contaminate soil and groundwater and pose harmful effects to public health and the environment. This study evaluated the feasibility of using volatile organic compounds (VOCs), total petroleum hydrocarbons (TPHs), electrical conductivity (EC), and pH to examine the contamination caused by leaking UFSTs. Screening water assessments for VOCs and general water quality parameters were conducted on the premises of 53 gas stations in Riyadh, Saudi Arabia, to identify potentially contaminated sites, and 25 ground bores were drilled for the quantification of TPH concentrations, EC, and pH values in 407 soil samples. The experimental approach followed in this study included geochemical analyses based on borehole drilling at five targeted gas stations, analyses of water samples from underground storage reservoirs, and analyses of soil core samples obtained from different depths to determine the degree of TPH contamination. Thirty-five VOCs were identified in the water samples collected from gas stations. Methylene chloride, tribromomethane, toluene, chlorobenzene, dibromochloromethane, and benzene were frequently encountered in most of the water samples. Some of these samples exceeded the World Health Organization and Saudi Arabian guidelines for acceptable levels of pH, total dissolved solids, chloride, nitrate, sulfate, calcium, and total hardness. The measured TPH levels were clearly indicative of subsoil contamination and subsequent accumulation in soil over time, particularly at depths of 1–6 m; there was not a noticeable dependence or impact on pH.

Effect of benzene and ethylbenzene on the transcription of methyl-tert-butyl ether degradation genes of Methylibium petroleiphilum PM1.

Methyl-tert-butyl ether (MTBE) and its degradation by-product, tert-butyl alcohol (TBA), are widespread contaminants detected frequently in groundwater in California. Since MTBE was used as a fuel oxygenate for almost two decades, leaking underground fuel storage tanks are an important source of contamination. Gasoline components such as BTEX (benzene, toluene, ethylbenzene and xylenes) are often present in mixtures with MTBE and TBA. Investigations of interactions between BTEX and MTBE degradation have not yielded consistent trends, and the molecular mechanisms of BTEX compounds' impact on MTBE degradation are not well understood. We investigated trends in transcription of biodegradation genes in the MTBE-degrading bacterium, Methylibium petroleiphilum PM1 upon exposure to MTBE, TBA, ethylbenzene and benzene as individual compounds or in mixtures. We designed real-time quantitative PCR assays to target functional genes of strain PM1 and provide evidence for induction of genes mdpA (MTBE monooxygenase), mdpJ (TBA hydroxylase) and bmoA (benzene monooxygenase) in response to MTBE, TBA and benzene, respectively. Delayed induction of mdpA and mdpJ transcription occurred with mixtures of benzene and MTBE or TBA, respectively. bmoA transcription was similar in the presence of MTBE or TBA with benzene as in their absence. Our results also indicate that ethylbenzene, previously proposed as an inhibitor of MTBE degradation in some bacteria, inhibits transcription of mdpA, mdpJ and bmoAgenes in strain PM1.

Investigation of gasoline distributions within petrol stations: spatial and seasonal concentrations, sources, mitigation measures, and occupationally exposed symptoms.

We measured levels of VOCs and determined the distributions of benzene concentrations over the area of two petrol stations in all three seasons. Using the concentrations and sampling positions, we created isoconcentration contour maps. The average concentrations ranged 18-1288 μg m(-3) for benzene and 12-81 μg m(-3) for toluene. The contour maps indicate that high-level contours of benzene were found not only at the fuel dispenser areas but also at the storage tank refilling points, open drainage areas where gasoline-polluted wastewater was flowing, and the auto service center located within the station area. An assessment of the benzene to toluene ratio contour plots implicates that airborne benzene and toluene near the fuel dispenser area were attributed to gasoline evaporation although one of the studied stations may be influenced by other VOC sources besides gasoline evaporation. Additionally, during the routine refilling of the underground fuel storage tanks by a tank truck, the ambient levels of benzene and toluene increased tremendously. The implementation of source control by replacing old dispensers with new fuel dispensers that have an efficient cutoff feature and increased delivery speed can reduce spatial benzene concentrations by 77%. Furthermore, a questionnaire survey among 63 service attendants in ten stations revealed that headache was the most reported health complaint with a response rate of 32%, followed by fatigue with 20%. These prominent symptoms could be related to an exposure to high benzene concentrations.

Applying pattern classification techniques to the early detection of fuel leaks in petrol stations

Abstract Leaks below the surface are one of the most serious problems in service stations with underground fuel storage tanks. These leaks result in pools of fuel, which flows into both the ground and the aquifers, polluting ecosystems and damaging them severely. In this paper, pattern classification techniques are used to carry out the early detection of fuel leaks in petrol stations. Early detection is crucial from an environmental point of view. The use of these classification methods requires properly selecting those variables that suitably represent the objects to classify, which in this case are the days when the petrol station is operative. In our study we use actual data provided by Repsol (a Spanish energy company) to construct these objects, which are then classified into two possible categories: “day without leaks” or “day with leaks”, applying both supervised and unsupervised classifiers. Finally, three different combinations of “classifier + feature group” are proposed as possible solutions for the problem of the early detection of fuel leaks in service stations.

Remediation of Site Contamination

The effect of industrial contaminants on human health came to world scientific prominence in the 1950s when human exposure to mercury (Hg) in Japan led to poisoning of thousands of local people (i.e. Minamata disease). Since that time, the effects of other contaminants such as arsenic, selenium, and asbestos has been reported in many countries. The race for economic growth inmost countries has seen a dramatic increase in industrial activities which in turn has led to an exponential rise in the production of toxic wastes, many of which were disposed of into land and water bodies. These activities coupled with underground fuel storage tanks, mining, and military activities have resulted in millions of potentially contaminated sites worldwide (Table 1) which are largely located in densely populated areas. At a conservative estimate, there are more than 5,000,000 potentially contaminated sites worldwide. These represent both a lost economic opportunity and a real threat to the health and wellbeing of humans and the natural environment. With half of the population now living in cities, the demand for residential properties has forced local councils, planners, and regulators to consider new ways to manage contaminated sites. However, these sites represent a growing challenge given the nature of contaminants and the presence of complex chemical mixtures in most sites. These mixtures result in major differences in the fate and behaviour of the contaminants in both the soil and ground water environment and so, make remediation extremely challenging. Although site contamination was recognised some 60 years ago, efforts to remediate have been hampered by the complex and challenging nature of contamination, lack of regulatory policies enforcing polluters to remediate, or lack of adequate financial support.

Investigation of Soil Aggressiveness towards Underground Fuel Storage Tanks and Water Pipelines in Parts of Bayelsa State, Southern Nigeria

Structural failure of buried cast/ductile iron water mains and tanks due to corrosion attacks manifests in leaks and is common in most cities throughout Nigeria. The appropriate corrective action, which aims to restore pipe/tank integrity is usually based on proper understanding of the degree of corrosiveness of the soil. In an attempt to determine the potential corrosiveness of the soil to buried metallic structures in Bayelsa State, surface geoelectrical sounding was carried out. Twenty-five Schlumberger Vertical Electrical Soundings (VES) was carried out in the freshwater and meander belt geomorphic zone and the salt water mangrove swamp and estuary complex of the state using a maximum current electrode separation ranging from 200 - 400 m. The data obtained was interpreted by computer iterative modeling using a 1D inversion technique software (1X1D, Interpex, USA). The results show a high degree of heterogeneity, both laterally and vertically, which is typical of a complex depositional environment. Generally, the sub-soil condition within the expected depth of installation of water mains and storage tanks (0 - 10 m) is slightly or moderately aggressive (effective aggressivity) in the freshwater and meander belt geomorphic zone but is very strongly aggressive in the salt water mangrove swamp and estuary complex. Corrosion cells which may lead to significant corrosion failures may occur in the vicinities of strongly aggressive stations. This poses a significant corrosion risk to metallic water pipes and storage tanks. Current day design should therefore either mandate the use of a non-metallic piping product (water mains) or cathodic protection system. Prediction of potential corrosiveness of a soil and thus the application of proper corrosion control measures will not only protect the environment from spillages but will also avert cost of repair, clean-up and replacement.

Evaluating and managing potential groundwater pollution from leaking USTs at a coastal city in saudi arabia

Leaking underground fuel storage tanks (USTs) are the main source of petroleum hydrocarbon contamination of soil and groundwater. The distribution and fl ow of the leaked hydrocarbon is infl uenced by capillary and gravity forces. Depending on the leaked volume and the soil properties, the hydrocarbon could exist as a residual phase completely held in the soil above the water table or as both free phase product and residual. Various components of gasoline will affect the groundwater quality and each will spread according to its own characteristics. The pollution processes are studied through the development of a combination of two models: a compositional and a potential fl ow model. The former was developed using the mass balance principle and is capable of using the organic compound and the subsurface properties to predict the concentration of the various components of benzene, toluene and xylene (BTX) mixture in a leachate from a site contaminated by a residual mixture. Potential fl ow theory was utilized to model the advective transport of contaminants towards municipal wells. Capture zones were defi ned and travel times for different municipal wells were estimated for a sample study area at a coastal city in eastern Saudi Arabia. Modeling and fi eld survey indicated the high potential for groundwater pollution and concluding that more effort should be directed to promote leak prevention through management strategies that include developing proper design regulations and installation requirements like monitoring wells for new and existing service stations.

Preliminary Results on the Effect of Methanol-Based Fuels on the Tensile Properties of Frp Micro-Specimens

This paper reports a simple experimental technique developed to measure strains in fibre-reinforced plastic (FRP) tensile micro-specimens (nominal thickness: 254 μm) before and after these were exposed to a 50–50 volumetric mixture of methanol and ASTM Fuel C. Micro-specimens were used to reduce the time required for the fuel mixture to diffuse into the FRP. The developed technique is then used to study the effect of the methanol-based fuel on the tensile properties of the micro-specimens. In particular, the stress of the specimens at a strain of 1.5% is seen to be significantly lower when the specimens are tested immediately after exposure to the fuel for 3 day and 7 day periods as compared to the stress for specimens not exposed to the fuel. The loss in stress is found to be significantly recoverable when the exposed specimens are tested after allowing them to dry for an equal length of time, i.e. 3 days and 7 days. These results point to two possibilities: 1. Design of FRP structures exposed to alcohol-based fuels, e.g. underground fuel storage tanks, may have to account for noticeable mechanical property changes of the FRP during the service period, 2. Any property changes may be partially reversed by allowing the structures to “dry” over an appropriate period of time.

MTBE in Southern California water

Motorized recreational watercraft were the predominant mode of contamination in reservoirs.Methyl tertiary butyl ether (MTBE) is a common fuel oxygenate used in motor vehicle fuels to control emissions and boost octane. It is more water‐soluble than other fuel constituents and does not adsorb well to substrates such as soil. It can contaminate groundwater supplies through leaking underground fuel storage tanks and pipelines, and through spills, urban storm runoff, and precipitation. It can also contaminate open water reservoirs through exhaust from motorized watercraft. The Metropolitan Water District of Southern California surveyed six reservoirs that supply drinking water in Southern California. Recreation on these reservoirs ranged from none at all to high activity with personal watercraft. It was found that motorized watercraft can contribute a significant amount of MTBE to the water supply.

Review of internal corrosion of underground fuel storage tanks

Leaking underground fuel storage tanks are a major environmental hazard in the U.S. Several studies have dealt with leaking tanks caused by external corrosion of the steel tanks. This review documents reports of tank leakage caused by internal corrosion and offers recommendations for preventing internal corrosion in underground tanks.

Innovative in situ treatment technologies for cleanup of contaminated sites

In situ treatment of waste and soil at contaminated sites offers an alternative to the traditional approach to site remediation involving excavation and redisposal or onsite isolation. The in situ “Detoxifier” is an innovative technology/equipment potentially capable of implementing a range of in situ treatment methods (e.g., air/steam stripping, neutralization, solidification/stabilization, oxidation, etc.). It is an adaptation of the drilling technology providing capabilities for in situ delivery of treatment agents in dry, liquid, slurry, or gaseous form to the soil and thorough mixing and homogenization of a vertical column of soil. The recent field demonstration of the mobile system in a full-scale site remediation application at a site in Southern California was documented. The soil at the site was contaminated with hydrocarbons from leaking underground fuel storage tanks. Steam and hot air were used to strip hydrocarbons from the soil; the off gas was processed in a treatment train and recycled to the soil. By adjusting treatment conditions, the total petroleum hydrocarbons concentration in the soil could be reduced from an initial level of 5,000 ppm or higher to less than 100 ppm. Based on field demonstration results, the equipment vendor is developing designs for a more powerful and compact Detoxifier with enhanced off gas treatment capabilities.

Organic Vapors at Underground Gasoline Tank Removal Sites

Abstract Leaking underground fuel storage tanks are a major public health concern of the 1980s. The discovery of these leaking tanks and the potential for groundwater contamination prompted legislation which requires monitoring of existing tanks and removal of those tanks found leaking. In San Diego County, the removal of an underground storage tank is witnessed by a Hazardous Materials Specialist (HMS). The HMS and the tank contractor (TC) who actually conducts the tank removal are both subject to exposure to organic vapors during this work activity. To investigate the organic vapors at gasoline tank removal sites, breathing zone and general air samples are collected on large (400/200 mg) charcoal tubes. Breathing zone samples were collected for both HMSs and TCs. General air samples were collected upwind and downwind from the site, three meters deep in the excavation and directly above the excavation at grade. Five gasoline tank removal sites were sampled. The samples were analyzed for pentane, n-hexane...

Precast Prestressed Underground Fuel Storage Tanks in Adak, Alaska

T paper describes the design and some construction aspects of three 55,000 barrel underground fuel storage tanks using plant cast, prestressed, segmental wall panels, The walls are post-tensioned circumferentially with the stressing tendons installed in ducts which are subsequently grouted. The use of concrete for the construction of storage tanks, particulary underground tanks, has several attractive features, including durability, good resistance to lateral forces, and protection from fire and other external hazards. The use of precast prestressed concrete has the added advantages of better quality control and lower on-site labor cost than cast-in-place concrete, particularly at a remote site such as Adak (see map, Fig. 1). Western Division, Naval Facilities Engineering Command (WESTNAVFACENGCOM), is responsible for the design and construction of shore