Underground Storage Leaks: Water Pollution's Hidden Threat

Underground storage tanks (USTs) are effective methods of storing substances for commercial, agricultural, and private use. However, they can pose a significant threat to the environment and public health if not properly maintained. USTs often store harmful substances such as petroleum and hazardous waste, and when they leak, these substances can contaminate soil and groundwater, leading to water pollution. This contamination can have detrimental effects on human health, causing issues such as cancer, organ damage, and developmental problems in children. As a result, understanding and preventing UST leaks are crucial to protect the environment and ensure safe drinking water for communities that rely on groundwater sources.

Corrosion, faulty installation, and inadequate maintenance can cause USTs to leak

Underground storage tanks (USTs) are used to store large quantities of gases or liquids. They are effective methods of storing substances for commercial, agricultural, and private applications. However, if not properly constructed and maintained, they can become massive liabilities. Corrosion, faulty installation, and inadequate maintenance can cause USTs to leak.

Corrosion is a common issue with USTs, especially those made of steel. Steel is a common material for USTs, especially in older tanks constructed before 1980. Depending on the soil conditions, some steel tanks can last for decades without corrosion, while others may start to corrode within 10 years. Newer tanks often employ cathodic protection systems to prevent oxidation (rust), which can help extend their lifespan. However, if the corrosion protection is not properly maintained, it may not be effective in preventing leaks.

Faulty installation is another cause of UST leaks. Subpar installation can lead to small leaks in fittings or pipes. Once the pipes are concreted in place, fixing these leaks can be costly and time-consuming. In some cases, the concrete may even temporarily hide the leak, allowing it to contaminate the environment for months before it is detected. It is important to ensure that installers have the knowledge and expertise to properly install USTs and that the tanks are compatible with the substances they are intended to store.

Inadequate maintenance can also contribute to UST leaks. Routine inspections, leak detection systems, and spill and overfill protection are crucial for preventing leaks. Owners and operators of USTs are required to follow certain regulations and standards, such as the Code of Federal Regulations, 40 CFR Part 280, which outlines technical standards and corrective action requirements. Regular maintenance and testing of USTs can help identify potential issues before they become leaks, reducing the risk to the environment and public health.

Leaking USTs contaminate soil and groundwater

Underground storage tanks (USTs) are large tanks that store substances like petroleum and hazardous materials for commercial, agricultural, and private use. They are often made from materials such as fiberglass, carbon fiber, and steel or aluminum. While they are effective storage solutions, USTs can pose significant environmental and health risks if they are not properly constructed and maintained.

Leaking USTs, also known as LUSTs, contaminate soil and groundwater. LUSTs are one of the primary sources of groundwater contamination, according to the National Water Quality Inventory report submitted to Congress by the EPA. In the EPA's 2000 report, 39 states reported LUSTs as a major contributor to groundwater contamination. This is due to the harmful substances stored within, such as petroleum products, motor oil, waste oils, and hazardous chemicals like lead, benzene, MTBE, and cadmium. When these substances leak, they seep into the surrounding soil and groundwater, leading to environmental and health issues.

The impact of LUSTs on groundwater is particularly concerning as nearly 50% of the US population and 99% of the rural population depend on groundwater as their primary source of drinking water. Contaminated drinking water can cause adverse health effects, including cancer, organ damage, and developmental problems in children. Benzene, for example, can cause dizziness, rapid or irregular heartbeat, and confusion when inhaled at high levels. Other contaminants released from LUSTs, such as toluene, xylene, and ethylbenzene, have not yet been identified as human carcinogens but can lead to symptoms like tiredness, weakness, memory loss, nausea, and skin and eye irritation.

To prevent and mitigate the risks associated with LUSTs, the EPA has implemented strict regulations and procedures. These include requiring tank owners and operators to take financial responsibility for leaks and promoting proper maintenance and operation of UST equipment. Additionally, prevention efforts have been strengthened, with a focus on understanding the causes of leaks, such as corrosion, and implementing routine inspections and maintenance programs to address potential issues proactively.

USTs store hazardous substances like petroleum and motor oil

Underground storage tanks (USTs) are used to store hazardous substances, including petroleum, motor oil, and other fuels and chemicals. These tanks are often located underground at gas stations for convenient storage. However, if these tanks leak or spill, they can cause soil contamination and groundwater pollution.

USTs that contain fuels and hazardous substances pose a significant threat to groundwater quality. Leaks from these tanks can contaminate not only the soil but also the groundwater, and even hydrologically connected surface water. This is a serious issue, especially in populated areas where public and domestic water supplies are concentrated. The cleanup process for such contamination can be challenging and costly, particularly if it involves a public source of drinking water.

Petroleum, motor oil, and other hazardous substances stored in USTs can have harmful effects on the environment and human health if they leak. These substances can contain volatile organic compounds (VOCs) and other pollutants, such as benzene, toluene, ethylbenzene, and xylenes (BTEX). Exposure to these contaminants has been linked to various health risks, including carcinogenic and teratogenic effects. Inhalation of benzene, for example, can cause dizziness, confusion, and rapid or irregular heartbeat.

To address the risks associated with USTs, federal and state leaking underground storage tank (LUST) programs have been implemented in the United States. These programs have overseen the cleanup of hundreds of thousands of leaking tank sites. Additionally, release prevention and leak-detection requirements have been established, and improved design and installation standards have been implemented to minimize the threat of new releases.

While advancements in UST technology have been made, leaks and spills can still occur due to various factors. Steel tanks, which are commonly used for USTs, can corrode and rust, leading to leaks. To mitigate this, modern steel tanks are required to be rust-proof and can be coated with composite materials. Fiberglass tanks, which are corrosion-resistant, have also gained popularity. Interstitial monitoring, which checks the space between tank walls, is recommended as a preferred method for leak detection.

Benzene, a contaminant released from USTs, is carcinogenic

Underground storage tanks (USTs) are tanks or piping networks that have at least 10% of their volume underground. They often store substances such as petroleum that can be harmful to the environment if released. Many USTs are leaking, which may increase the risk of exposure to contaminants that pose health problems for nearby communities.

One of the contaminants released from leaking USTs is benzene, which is a known carcinogen. Benzene can be released directly into the atmosphere, and it can also move through soils and into nearby buildings, contaminating indoor air in a process called vapour intrusion. When inhaled at high levels, benzene can cause confusion, dizziness, rapid or irregular heartbeat, and loss of consciousness.

The US Environmental Protection Agency (EPA) has identified benzene as one of several contaminants of concern from USTs, along with methyl tert-butyl ether (MTBE), toluene, ethylbenzene, and xylenes (BTEX). MTBE is a particular concern as it readily evaporates into the air and soil, and the EPA is studying its potential health effects and occurrence.

The EPA's federal UST regulations have helped reduce soil and groundwater contamination by MTBE and other fuel components from USTs. However, not all UST systems are regulated, and equipment failures and installation mistakes can still result in fuel releases into the environment.

In addition to benzene, other contaminants released from USTs, such as toluene and xylene, have been identified as human carcinogens. The health effects of exposure to these contaminants include tiredness, confusion, weakness, drunken-type actions, memory loss, nausea, loss of appetite, hearing loss, colour vision loss, and irritation of the skin, eyes, nose, and throat.

The EPA has strict regulations for UST leaks

Underground storage tanks (USTs) often contain hazardous substances such as petroleum, which can be extremely harmful to the environment if they leak. As a result, the US Environmental Protection Agency (EPA) has implemented strict regulations to prevent and manage leaks.

The EPA's UST regulations aim to ensure that UST systems are properly designed, constructed, installed, and maintained. For example, UST systems must be designed and constructed to prevent corrosion, a common issue with older tanks that can lead to leaks. The EPA also requires the use of industry codes and standards to ensure the safe management of UST systems, including their upgrading, repairing, and closing.

To address the risks associated with leaking USTs, the EPA has established financial responsibility requirements for UST owners and operators. This includes covering the costs of corrective actions and compensating third parties for any injuries or property damage caused by leaking tanks. The EPA has also directed the creation of a Leaking Underground Storage Tank (LUST) Trust Fund to oversee and enforce cleanups, including at sites where the responsible party is unknown or unwilling to act.

In addition to these measures, the EPA has implemented several other initiatives to prevent and mitigate the impacts of UST leaks. For instance, the agency has developed resources to help UST owners and operators prepare for and reduce the environmental harm caused by natural disasters. The EPA also works in partnership with states, territories, tribes, and industry to protect human health and the environment from potential releases.

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