GAO Report Finds Problems with EPA Groundwater Protection Program

The U.S. Environmental Protection Agency (EPA) is not adequately monitoring more than 172,000 wells used to enhance oil and gas drilling and dispose of drilling wastewater, according to a July 28 report by the Government Accountability Office (GAO). The report, based on two years of research, identified several significant problems with EPA's program to protect groundwater from drilling chemicals and wastes. Since millions get their drinking water from groundwater, these problems raise significant questions about how effectively and consistently we are protecting public drinking water.

EPA's Groundwater Protection Program

The Safe Drinking Water Act gives EPA authority to regulate underground injections of hazardous and non-hazardous fluids in order to protect drinking water from contamination. EPA's Underground Injection Control (UIC) class II program, as it is formally known, sets standards for fluid wells, covering well construction, operation, monitoring and testing, completion, and more. Thirty-nine states manage their own programs that incorporate EPA-required safeguards, while EPA regional offices oversee wells in the remaining states.

Class II wells include three types of wells – enhanced recovery wells, where drilling fluids are pumped into existing wells in order to increase production; disposal wells, where drilling waste is disposed of through underground injection; and storage wells, which contain liquid petroleum products. Of these, enhanced recovery wells are the most common and make up around 80 percent of all class II wells.

Hydraulic fracturing (fracking) wells are excluded from the program, despite the rapid expansion of the drilling method and the serious groundwater contamination risks it poses. This is due to a provision in the Energy Policy Act of 2005 – known as the "Halliburton Loophole" – that exempts fracking fluid injection and wells from EPA oversight under the Safe Drinking Water Act (except when diesel fuel is used). However, when additional fluids are injected into a well to enhance natural gas/oil recovery, or when fracking waste fluids are disposed of by injecting them underground, those activities are covered by the UIC program.

The GAO Report

Roughly half of the U.S. population relies on groundwater for drinking water, and in rural areas, this figure rises to nearly 100 percent. Over two billion gallons of drilling fluids are pumped into class II wells each day, posing a direct threat to the drinking water so many Americans rely upon. With these risks in mind, the Government Accountability Office (GAO) examined the UIC program to determine whether it is adequately protecting this vital resource.

The GAO report reviewed well monitoring in eight states, six of which manage their own EPA-approved programs and two that are overseen by EPA regional offices. The report reviewed safeguards, agency evaluations, and the reliability of reported data. The investigation revealed the efforts these programs are taking toward protecting groundwater but also shed light on areas in need of improvement.

Safeguards do not address emerging risks

Each of the eight states has safeguards designed to prevent drilling fluids from contaminating groundwater, which include pre-construction reviews of well sites, instructions for well casing, and periodic well testing. According to state programs and EPA officials, these safeguards have proven successful and have resulted in few incidents of contamination. However, most state programs do not require groundwater testing, so it is difficult to verify whether these standards are truly effective in preventing contamination. GAO did not provide any recommendations on such testing, even though it could provide valuable data on the effectiveness of current safeguards.

Moreover, EPA has not reviewed such policies since the 1990s, meaning they do not address emerging risks associated with the increase in fracking wastewater disposal. For instance, there is evidence that wastewater injection may pose a risk for increased seismic activity. Earthquakes can compromise well integrity, cracking them and increasing the risk that toxic fluids could contaminate drinking water sources.

Another emerging hazard can be caused by "overpressurization" of a well, in which high-pressure injections can force drilling fluids back to the surface. Wastewater spilled on the surface can be absorbed into the ground and may find its way into nearby aquifers and contaminate groundwater.

While EPA is investigating the risk of increased seismic activity, the agency plans to address overpressurization on an individual state basis. GAO concludes that without a national survey of risks associated with overpressurization, EPA's program lacks the information it needs to protect groundwater. GAO advises EPA to address overpressurization in a national report in order to provide valuable information to all states on this risk.

EPA is not fulfilling two enforcement requirements

EPA is tasked with monitoring and evaluating state programs in order to determine whether their requirements are protecting groundwater. Moreover, EPA policies require that the agency incorporate state requirements into federal regulations through a rulemaking process. However, GAO notes that the agency has fallen behind in incorporating state requirements and therefore may be unable to enforce many of them. When pressed on this issue, EPA responded that the rulemaking process is costly and burdensome. While this may be true, the importance of protecting the public’s drinking water would seem to outweigh any such administrative burden.  GAO suggests that EPA issue a single rulemaking to incorporate state regulations and then investigate whether there are more efficient ways of achieving this.

EPA must also conduct additional oversight activities, including reviewing state program reporting and conducting annual, on-site evaluations. The agency is fulfilling the review requirements but in many cases is not conducting annual visits, citing the costliness of such trips. Moreover, EPA has not updated its guidance for oversight since the 1980s, meaning the agency is unable to determine whether current oversight procedures are still effective. GAO recommends that EPA update its guidance policies to determine the most effective oversight activities given the agency's resource constraints and to follow through with on-site evaluations that ensure state programs are protecting groundwater.

Reported data is inconsistent and therefore difficult to use

Well operators, as well as state programs and EPA regional offices, are required to submit forms to EPA documenting injection activities, monitoring data, and compliance evaluation. These data are essential for evaluating the effectiveness of the groundwater protection programs. However, GAO notes certain inconsistencies in reporting, including differing interpretations by states and the lack of reporting reviews to check for completeness.

Because of these issues, it is difficult to compare data among states when they interpret forms differently or leave out essential information. Moreover, many forms are submitted on paper, creating processing delays and making it more difficult for the public to access records.

EPA is currently working to create a national UIC database with electronic reporting requirements that should address these problems, but the tool will not be complete for another two to three years. In the meantime, GAO urges EPA to improve reporting by making it more consistent and by checking for data quality. This will allow data to be more useful to the public while the national UIC database is being finalized.


The GAO report reinforces the importance of well monitoring and the need for improvements to EPA's program to protect groundwater from contamination. It also illustrates that many of the problems with EPA's oversight of the program are related to limited agency resources and funding, which have grown more constrained in the current era of misguided federal budget austerity.

In spite of these limitations, GAO asserts that EPA can do much to better ensure the effectiveness of the UIC groundwater protection program. It is imperative that EPA follow the GAO's constructive recommendations and take appropriate steps to ensure that injection wells are not poisoning the drinking water of millions of Americans.

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