Hydraulic Fracturing: Water Pollution And Its Causes

Hydraulic fracturing, or fracking, is a multi-step fossil fuel extraction process that has expanded oil and gas development and water resource risks. The process involves drilling vertically and horizontally into rock formations, detonating charges to blast fissures open, and injecting a mix of water, chemicals, and proppants into the underground rock layers to further fracture the rock. While fracking has made fossil fuels big business in the United States, there are concerns about its impact on water supplies and the environment. EPA studies have found scientific evidence that hydraulic fracturing activities can impact drinking water resources under certain conditions, and there is mounting evidence that it poses serious threats to health, the environment, and our climate future.

Chemicals in fracking fluid can contaminate groundwater

The US Environmental Protection Agency (EPA) has identified several ways in which chemicals in fracking fluid can contaminate groundwater. Firstly, during the "water acquisition" stage, water withdrawals for hydraulic fracturing can occur in times or areas of low water availability, particularly in regions with limited or declining groundwater resources. This can strain local water resources and increase the risk of pollution.

Secondly, spills during the handling, management, and transportation of hydraulic fracturing fluids, chemicals, or produced water can result in large volumes or high concentrations of chemicals reaching groundwater resources. For example, if a well is improperly installed, or if chemicals are spilled from trucks or tanks, contaminants can leak into groundwater supplies.

Thirdly, the injection of hydraulic fracturing fluids into wells with inadequate mechanical integrity can allow gases or liquids to migrate into groundwater resources. Additionally, the direct injection of hydraulic fracturing fluids into groundwater resources can result in contamination.

Lastly, the discharge of inadequately treated hydraulic fracturing wastewater into surface water resources and the disposal or storage of this wastewater in unlined pits can also contaminate groundwater. The EPA's report highlights that data gaps and uncertainties limited their ability to fully assess the potential impacts on drinking water resources, both locally and nationally. However, the available evidence suggests that the chemicals used in fracking have the potential to affect both groundwater and surface water quality, posing risks to human health and the environment.

Poorly constructed wells can cause shallow aquifer pollution

Poorly constructed wells are a significant concern when it comes to hydraulic fracturing and water pollution. The process of hydraulic fracturing, or fracking, involves injecting a mix of water, chemicals, and proppants (like sand) at high pressure into underground rock layers to extract oil and natural gas. This process can lead to water pollution in several ways, especially when wells are improperly installed or maintained.

One issue with poorly constructed wells is the potential for shallow aquifer pollution. After the well is fracked and starts producing oil and gas, some of the fracking fluid remains underground. If the wells are not properly constructed, the fracking fluid can contaminate groundwater if fractures connect to aquifer systems. This can result in the pollution of shallow aquifers with chemicals and methane. Improper well construction can also lead to “communication” between production wells and drinking water wells, further increasing the risk of contamination.

In addition to construction issues, improperly installed or maintained wells can also lead to water pollution. This includes spills of chemicals or produced water during the fracking process, which can reach groundwater resources. Inadequate mechanical integrity of wells can allow gases or liquids from fracking fluids to migrate into groundwater. Furthermore, the discharge of inadequately treated fracking wastewater into surface water can contaminate water sources.

The impact of well construction on water pollution is a serious concern, as highlighted by studies such as the one conducted in the Permian Basin region of West Texas. Between 2011 and 2016, water use for fracking in this region increased significantly, and the amount of wastewater generated during the first year of production surged by up to 1,440%. This intensification of fracking activities exacerbates the risk of water pollution, especially when wells are not properly constructed or maintained.

To address these concerns, regulations and proper well construction and maintenance practices are crucial. While the US EPA has found scientific evidence that hydraulic fracturing activities can impact drinking water resources, there are still data gaps and uncertainties that hinder a full understanding of the severity and frequency of these impacts. Therefore, continued research, monitoring, and targeted programs are necessary to protect water resources and human health from the potential dangers of hydraulic fracturing.

Flowback and wastewater can pollute water sources

Hydraulic fracturing, or fracking, is a multi-step oil and natural gas extraction process. Once the well is drilled, a charge is detonated to blast fissures open, and then a mix of water, chemicals, and proppants are injected into the underground rock layers at high pressure to further fracture the rock. Once the production well is fully open, some "produced" wastewater flows back to the surface, and finally, the oil and natural gas are extracted. This process is vital to fracking and requires millions of gallons of fracking fluid for each well.

The amount of water used per fracking job has increased over time, exacerbating the impact on water supplies. For example, a study found that water use for fracking in the already drought-ridden Permian Basin region of West Texas increased by up to 770% between 2011 and 2016. The amount of wastewater generated during a well's first year of production in the same period increased by up to 1,440%.

The wastewater is often pumped into holding ponds, from where it can leak and settle into the surrounding groundwater, impacting wildlife and drinking water wells. There is evidence that shallow aquifers have been polluted by methane due to poorly constructed production wells or "communication" between production wells and drinking water wells. The contamination of watersheds that provide drinking water for millions of people in cities far from any natural gas drilling sites poses a significant threat.

The discharge of oil and gas wastewater impacts water and sediment quality on a larger scale than previously thought. Large quantities of oil and gas wastewater with high loads of chloride, barium, strontium, radium, and organic compounds leave high concentrations in the sediments and pore water. Two important types of organic contaminants found in the wastewater are endocrine-disrupting chemicals (nonylphenol ethoxylates) and carcinogens (polycyclic aromatic hydrocarbons).

Water withdrawals for fracking can strain water resources

The amount of water used for fracking varies depending on factors such as the type of well and rock formation. On average, a single fracking operation in the United States can use between 1.5 million and 9.7 million gallons of water, according to the USGS. However, this number can be much higher in certain cases, such as the fracking operation in the Horn River Basin in Canada, which used almost 16 million gallons of water.

The water used for fracking is typically freshwater taken from groundwater and surface water resources. While there are efforts to use non-potable water, some of these sources also supply drinking water, which puts them at risk of contamination. In regions with limited water resources, such as Texas, Colorado, and other arid states, the competition for water between fracking operations, agriculture, and residential use is becoming increasingly intense.

The impact of water withdrawals for fracking is exacerbated by the fact that a significant portion of the injected water returns to the surface as wastewater or flowback. This wastewater can contain chemicals and other pollutants, further straining water treatment and disposal systems.

The strain on water resources due to fracking is a significant concern, and it has led to increased scrutiny and regulation of the practice. Understanding the dynamics of water usage and the potential impact on water resources is crucial for landowners and policymakers to make informed decisions about the balance between resource extraction and environmental protection.

Air pollution from fracking can indirectly impact water quality

Compressor stations used in fracking have been linked to air, water, and soil pollution, as well as noise pollution. A case in Dish, Texas, where residents experienced health issues after 11 compressor stations were built, illustrates this. An air quality study revealed high levels of carcinogens and neurotoxins, including benzene, which can have long-term health risks.

In addition, fracking releases airborne contaminants, such as volatile organic compounds and nitrogen oxides, which contribute to smog formation. This can have detrimental effects on human health. Areas with gas production have reported increased ozone levels, which are linked to respiratory issues and potentially dangerous changes in the heart.

Furthermore, fracking emits sulfur dioxide (SO2), which can react with other chemicals to form particulate pollution during well construction or from diesel exhaust. Sulfur dioxide can have negative impacts on respiratory and cardiovascular health.

The release of methane, a potent greenhouse gas, during fracking operations is also a concern. Methane can contribute to global climate change and has a higher potential to trap heat than carbon dioxide. While the direct impact of methane on water quality may be indirect, the indirect effects on water resources cannot be overlooked.

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