DOD has two types of public water systems that provide drinking water to people that live and work on military installations. The first type provides drinking water that has been treated by DOD. The second type provides water treated by a private company or a local utility, which we refer to as “non-DOD-treated” drinking water. Drinking water systems vary by size and other factors, but they most typically include a supply source, treatment facility, and distribution system. A water system’s supply source may be a reservoir, aquifer, well, or a combination of these sources. The treatment process for surface water generally uses sedimentation, filtration, and other processes to remove impurities and harmful agents, and disinfection processes such as chlorination to eliminate biological contaminants. Distribution systems are comprised of water towers, piping grids, pumps, and other components to deliver treated water from treatment systems to consumers. EPA regulates drinking water contaminants under the Safe Drinking Water Act by issuing legally enforceable standards, known as National Primary Drinking Water Regulations, which generally limit the levels of these contaminants in public water systems. EPA has issued such regulations for approximately 90 drinking water contaminants. In accordance with the Safe Drinking Water Act, EPA may authorize a state to have primary enforcement responsibility for drinking water regulations, as long as the state has, among other things, drinking water regulations that are no less stringent than the National Primary Drinking Water Regulations. The Safe Drinking Water Act also authorizes EPA to take emergency actions necessary to protect public health when informed that a contaminant is present in or is likely to enter a public water system or an underground source of drinking water that may present an imminent and substantial endangerment. For example, EPA may issue administrative orders, which generally include actions to be taken, such as remediating contaminated sources of drinking water or requiring the provision of alternative water supplies. State regulators may also issue orders to public water systems to address contaminated drinking water. Public water systems, including the DOD public water systems that provide drinking water to about 3 million people living and working on military installations, are required to comply with EPA and state drinking water regulations. EPA divides violations of drinking water regulations into two types: (1) health-based violations and (2) other types of violations that include violations of monitoring, reporting, and public notification requirements. Under the Safe Drinking Water Act, EPA also is required to identify unregulated contaminants that present the greatest health concern, establish a program to monitor drinking water for unregulated contaminants, and decide whether or not to regulate at least five such contaminants every 5 years. EPA has not regulated any new contaminants using this process since 1996. DOD’s environmental compliance policy states that ASD (EI&E) is responsible for providing guidance, oversight, advocacy, and representation for environmental compliance programs—to include overseeing the military departments’ compliance with health-based drinking water regulations at DOD public water systems. The policy directs the military departments to annually report to ASD (EI&E) the total population receiving water from both “regulated” and “other” DOD public water systems—referred to in this report as DOD public water systems that provide DOD- and non-DOD-treated drinking water, respectively— that did and did not attain all Safe Drinking Water Act health-based drinking water standards. The policy also requires the military departments to report information regarding each instance health-based drinking water standards were not attained during the reporting period, to include the name and location of the military installation; the nature of the issue (e.g., the contaminant type); the DOD population affected; the duration of the issue; the corrective actions taken or planned (e.g., flushing the system, resampling the water, or implementing system upgrades); and the estimated date for achieving the standard. In addition to issuing drinking water regulations, EPA may also publish drinking water health advisories. In contrast to drinking water regulations, health advisories are nonenforceable. Drinking water health advisories provide technical guidance on health effects, analytical methodologies, and treatment technologies. These advisories recommend the amount of these contaminants that can be present in drinking water—”health advisory levels”—at which adverse health effects are not anticipated to occur over specific exposure durations, to include 1 day, 10 days, several years, or over a lifetime. EPA issues provisional health advisories to provide information in response to an urgent or rapidly developing situation. DOD’s list of emerging contaminants includes 11 contaminants, including PFOS, PFOA, and perchlorate, for which EPA has issued a drinking water health advisory. Specifically, PFOS. PFOS is part of a larger group of fluorinated organic chemicals that have been incorporated into an array of consumer products (i.e., to make some more resistant to stains, grease, and water) and also in firefighting foam used by DOD and civilian airports. According to EPA, the major manufacturer of PFOS in the United States voluntarily agreed to phase out production of the chemical in 2002. According to EPA’s health advisory, exposure to PFOS may remain possible due to legacy uses, existing and legacy use in imported goods, and the chemical’s “extremely high persistence” in the environment. According to the EPA, exposure to PFOS may result in adverse health effects, such as fetal developmental effects during pregnancy or to breastfed infants, cancer, liver damage, immune effects, thyroid effects, and other effects. See table 1 for details of the EPA provisional health advisory that was issued in 2009 and the lifetime health advisory that was issued in 2016, which superseded the provisional health advisory. PFOA. PFOA is a fluorinated organic chemical that has been used in generally the same products as PFOS, including firefighting foam used by DOD and civilian airports. According to EPA, PFOA was voluntarily phased out by eight major companies in the manufacturing of their products at the end of 2015. According to the EPA, adverse health effects from exposure to PFOA are similar to those for PFOS. See table 1 for details of the EPA provisional health advisory that was issued in 2009 and the lifetime health advisory that was issued in 2016, which superseded the provisional health advisory. Perchlorate. Perchlorate is commonly used in solid propellants, fireworks, matches, signal flares, and some fertilizers, and has been used by DOD for rocket fuel and ammunition. EPA published an interim health advisory for perchlorate in 2008; the interim health advisory level was set at 15 parts per billion. According to the health advisory, perchlorate can disrupt the functions of the thyroid gland. In 2009, DOD issued a policy on the identification, assessment, and risk management of emerging contaminants that have the potential to impact DOD. According to that policy, chemicals and materials used or planned for use by DOD that meet the definition of an emerging contaminant should be identified as early as possible. The policy further states that DOD is to assess and, when appropriate, take action to reduce risks posed by its emerging contaminants to people; the environment; and DOD missions, programs, and resources. Where necessary, DOD is to perform sampling, conduct site-specific risk assessments, and take response actions for emerging contaminants released from DOD facilities, in accordance with relevant statutes. According to the DOD policy on emerging contaminants, ASD (EI&E) is to develop and maintain a list of emerging contaminants with potential or probable high risk to the department’s personnel and functions. As of April 2017, DOD’s list of emerging contaminants comprised 49 chemicals or substances. According to our analysis of EPA documents, DOD’s list includes 21 contaminants that can be found in drinking water. Of these 21 contaminants, 10 contaminants have been regulated by EPA under the Safe Drinking Water Act, and 11 contaminants are currently unregulated but have an EPA-issued drinking water health advisory. The other 28 DOD-identified emerging contaminants do not have EPA drinking water regulations or health advisories. Appendix II provides more information on the drinking water regulatory status of DOD-identified emerging contaminants. For the years we reviewed—fiscal years 2013 through 2015—the military departments annually reported information internally to ASD (EI&E) on compliance with EPA and state health-based drinking water regulations, which indicate that drinking water quality at DOD public water systems was similar to other systems in the United States. However, not all violations of health-based regulations were reported to ASD (EI&E) during this time frame, as is required by DOD policy. The military departments reported that a total of 77 military installations had at least one violation at some point from fiscal year 2013 through fiscal year 2015, but we found that at least 16 additional installations had violations that were reported to EPA but were not internally reported to ASD (EI&E). DOD also has not used available compliance data to identify why DOD public water systems that provide DOD-treated drinking water appear to have more violations of health-based regulations than DOD systems that provide non-DOD- treated drinking water. For the years we reviewed—fiscal years 2013 through 2015—the military departments annually reported information to ASD (EI&E) on compliance with and violations of EPA and state health-based drinking water regulations at the DOD public water systems that provide drinking water to military installations. The military departments’ data for fiscal years 2013 through 2015 indicate that about 92 percent of people who received drinking water from DOD public water systems were served by a system that complied with EPA and state health-based regulations. This is similar to the percentage of people in the United States—also about 92 percent, according to EPA—who received drinking water during that time frame from a community public water system with no health-based violations. The data for that time period also indicate that about 8 percent of people were provided drinking water from a DOD public water system that had at least one violation of a health-based regulation. Health-based violations can be for any length of time during a fiscal year—for example, a violation lasting 1 day is counted the same as a violation lasting for 1 month. Across the 3 fiscal years, the military departments reported that a total of 77 military installations had at least one violation at some point during that time period: 35 in fiscal year 2013, 25 in fiscal year 2014, and 17 in fiscal year 2015. The most common types of contaminants for which the military departments reported violations were coliform and two disinfection byproducts—trihalomethanes and haloacetic acids—which, according to EPA, are among the most common types of contaminants for which health-based drinking water violations occur across the United States. However, we found that the military departments have not always reported all violations to ASD (EI&E), as required by DOD policy. Based on our review of data in EPA’s Safe Drinking Water Information System for fiscal years 2013 through 2015, we found that the military departments did not report violations to ASD (EI&E) for at least 16 installations—9 Air Force installations, 5 Navy installations, and 2 Army installations. According to EPA’s database, the total population served by DOD public water systems at these installations is approximately 180,000 people, and most of the violations that went unreported involved coliform and disinfection byproduct contaminants. However, the actual population number affected by these violations and the contaminants involved— along with other information such as the duration of the contamination and the corrective actions planned or taken—were not included in the military departments’ annual reports to ASD (EI&E). These violations were recorded in EPA’s system, which indicates that the installations reported the violations to the appropriate state regulatory agencies, who then reported them to EPA’s database. However, the violations were not reported to ASD (EI&E), as required by DOD policy. According to military department officials, violations of health-based drinking water regulations went unreported to ASD (EI&E) due to a lack of clarity in DOD’s reporting requirements and misunderstandings of the requirements on the part of installations and the military departments. We found that violations were either not reported by the military installations where the violations occurred or that they were not reported by the installations’ chains of command. Navy officials cited turnover of installation personnel as the reason some violations went unreported, as well as misinterpretations by installation personnel of DOD’s reporting requirements. Air Force officials also told us that most of their unreported violations were not reported to ASD (EI&E) because the Air Force did not interpret them as health-based violations, although DOD policy requires these types of violations to be reported. Army officials told us that, based on their interpretation of DOD’s policy, the policy did not require them to report violations at installations where formal, written notification was not received from the state regulatory agency. However, ASD (EI&E) officials stated that all violations of health-based regulations should be reported, whether or not the state provides formal, written notification of the violation. Navy officials also told us that they have not reported violations at some of the Navy’s smaller systems that purchase drinking water from non-DOD public water systems, due in part to misinterpretation of DOD’s internal reporting requirements. However, Navy officials told us that ASD (EI&E) had instructed them to begin reporting these types of violations in fiscal year 2016, and the Navy is working with ASD (EI&E) and the other military departments to determine whether these types of systems should regularly report health-based violations. Currently, ASD (EI&E) does not have complete data in accordance with DOD’s policy, limiting its ability to conduct oversight and analyze how many people at military installations receive drinking water with health- based violations, what contaminants were involved, the duration of the contamination, or what corrective actions the military departments have planned or taken to address the violation. Standards for Internal Control in the Federal Government states that quality information is needed to achieve an organization’s objectives. Those standards also indicate that actions such as improved communication to and additional training for personnel are helpful for an organization to meet its objectives. According to DOD officials, a committee comprised of ASD (EI&E) and military department officials began a review in 2016 of DOD’s internal reporting requirements for drinking water compliance data. While such a committee could be in a position to make recommendations on clarifying the annual reporting requirements, no documentation on the committee’s efforts was yet available at the time of our review as the committee’s work was still in progress. In addition, at present, there are no firm dates for when its work will be completed or when any potential changes would be implemented. Absent actions by ASD (EI&E) to identify and implement any necessary changes to clarify annual reporting requirements in its environmental compliance policy, and absent actions by the military departments to increase understanding at their installations and commands about the requirements, adherence to DOD’s environmental compliance policy will remain limited and DOD will lack complete data to conduct oversight of regulatory compliance at its public water systems. DOD has not used available data to assess why DOD public water systems providing DOD-treated drinking water appear to have more violations of health-based drinking water regulations than systems providing non-DOD-treated drinking water. Although we found that not all violations were reported by the military departments to ASD (EI&E), the data that were reported during fiscal years 2013 through 2015 indicated that about 99 percent of the people who received non-DOD-treated drinking water were served by systems with no violations, while about 89 percent of the people who received DOD-treated drinking water were served by systems with no violations. When we asked ASD (EI&E) and military department officials why these differences may exist, they were unable to provide an explanation because they had not used the reported water quality data to identify the reasons why DOD public water systems providing DOD-treated water appear to have more violations than systems providing non-DOD-treated water. Although some officials offered ideas on the reasons for differences in compliance—including the relative expertise of utilities and private companies, versus DOD, in providing drinking water—DOD officials acknowledged that the agency has not evaluated the data to identify specific reasons for why the differences may exist. All public water systems, including DOD public water systems, are required to comply with applicable EPA and state drinking water regulations. According to Standards for Internal Control in the Federal Government, management should establish and operate activities to monitor the internal control system and evaluate the results. Such monitoring should assess the quality of performance over time and promptly resolve any findings. Without reviewing the data reported by the military departments to identify why there appear to be differences in violations between DOD’s two types of public water systems and without identifying and implementing any actions to address any differences, ASD (EI&E) and the military departments may not be able to improve overall compliance with health-based drinking water regulations. DOD is taking steps to address health and environmental concerns with its use of firefighting foam that contains PFCs—including PFOS and PFOA—to include restricting the use of foam at its installations and funding research into the development of a PFC-free foam that can meet DOD performance requirements. DOD also has responded to EPA and state orders and initiated additional actions to address elevated levels of PFOS, PFOA, and perchlorate. DOD is taking steps to address PFOS- and PFOA-related health and environmental concerns with its use of firefighting foam that contains PFCs. Firefighting foam is used by DOD to put fires out quickly while also ensuring that they do not reignite. This is critical if, for example, there is a fire from a fighter jet on the deck of an aircraft carrier. DOD has outlined performance requirements in its military specification for firefighting foam, which was authored by the Navy’s Naval Sea Systems Command but is approved for use in all of DOD. For example, the military specification states how long it should take for firefighting foam to extinguish a fire—based on the size of the fire and the amount of foam used—and how long the foam should prevent the extinguished fire from reigniting. DOD’s military specification also requires that firefighting foam purchased and used by the department must contain PFCs. DOD’s steps to address concerns with the use of firefighting foam include restricting the use of existing foams that contain PFCs; testing its current foams to identify the amount of PFCs they contain; and funding research into the future development of PFC-free foam that can meet DOD’s performance and compatibility requirements (see table 2). Some of these steps, such as limiting the use of firefighting foam containing PFCs, are in place. Others, such as determining the specific amount of PFCs in existing firefighting foams or researching potential PFC-free firefighting foams, are in progress with targets, in some cases, but no firm completion dates. Navy officials stated that they are planning to revise the military specification after they have completed their testing—to be completed in late 2017 or 2018—on the amounts of PFOS, PFOA, and other PFCs found in the firefighting foam currently used by DOD. That revision, according to Navy officials, is intended to set limits for the amount of PFCs that are allowed in firefighting foam. According to DOD, at present there is no PFC-free firefighting foam that meets DOD’s performance and compatibility requirements. As a result, the Navy has no plans to remove the requirement for firefighting foam to contain PFCs at this time. However, if a PFC-free foam is developed in the future that can meet DOD performance and compatibility requirements, Navy officials said that any necessary revisions to the military specification would be made at that time—a process that could take months to complete. DOD has taken steps to respond to four administrative orders directing the department to address PFOS and PFOA levels that exceeded EPA’s health advisory levels for drinking water. One order was issued by the Ohio Environmental Protection Agency at Wright-Patterson Air Force Base in Ohio, and three orders were issued by the EPA directed at: the former Pease Air Force Base in New Hampshire; Horsham Air Guard Station in Pennsylvania; and the former Naval Air Warfare Center Warminster in Pennsylvania. Under Section 1431 of the Safe Drinking Water Act, EPA may issue orders necessary to protect human health where a contaminant in a public water system presents an imminent and substantial endangerment. EPA may do so if appropriate state and local authorities have not acted to protect human health. These orders may require, among other things, carrying out cleanup studies, providing alternate water supplies, notifying the public of the emergency, and halting disposal of the contaminants threatening human health. The Ohio Environmental Protection Agency has similar authority. According to information provided by officials from the Ohio Environmental Protection Agency, EPA, and DOD, DOD has taken steps to respond to the administrative orders. Table 3 provides further details on each order and examples of actions by DOD to address the orders. In addition to actions specific to these four installations, DOD has initiated other actions to test for, investigate, and mitigate elevated levels of PFOS and PFOA at or near installations across the military departments. Following the release of EPA’s lifetime health advisory for PFOS and PFOA in May 2016, each of the military departments issued guidance directing installations to, among other things, test for PFOS and PFOA in their drinking water and take steps to address drinking water that contained amounts of PFOS and PFOA above the EPA’s lifetime health advisory level. The military departments also directed their installations to identify locations with a known or suspected prior release of PFOS and PFOA and to address any releases that pose a risk to human health— which can include people living outside DOD installations. As a result of these efforts, DOD has initiated actions to address PFOS and PFOA in drinking water both on military installations and outside military installations. As of March 2017, DOD data indicated that the department was taking steps to address levels of PFOS and PFOA above the EPA’s lifetime health advisory level in drinking water on 11 military installations in the United States, 2 of which we visited during the course of this review (see fig. 1). According to DOD data, these installations took various corrective actions to mitigate the presence of PFOS and PFOA in the drinking water, including shutting down drinking water wells, providing alternative drinking water, and installing treatment systems. For example, at Eielson Air Force Base in Alaska, the Air Force reported shutting down three of the installation’s six drinking water wells and installing a treatment system to remove PFOS and PFOA from the drinking water. At Marine Corps Base Camp Pendleton in California, the Navy reported that a well contaminated with PFOS and PFOA was taken out of service and that the affected reservoir was drained and replaced with water from another source; follow-on testing showed that the presence of PFOS and PFOA were returned to below the EPA’s lifetime health advisory level. At Fort Leavenworth in Kansas, the Army reported that the private company that operates the installation’s drinking water system had shut down two wells contaminated with PFOS and PFOA and plans to install a treatment system before returning those wells to service. Additionally, according to DOD data as of December 2016 the military departments had identified 391 active and closed installations with known or suspected releases of PFOS and PFOA, and had reported spending almost $200 million on environmental investigations and mitigation actions at or near 263 (or about 67 percent) of those installations. In particular, DOD had initiated mitigation actions, which include installing treatment systems or supplying bottled water, to address PFOS and PFOA in drinking water for people living outside 19 installations—5 of which we visited during the course of this review (see fig. 2). The following cost data provided by DOD were current as of December 2016, and are supplemented by additional information we obtained during our installation visits. The Air Force identified 203 installations with known or suspected releases of PFOS and PFOA, spent about $120 million on environmental investigations at those installations, and spent about $33 million on mitigation actions at or near 14 of the 203 installations. For example, the Air Force reported spending over $5 million on environmental investigations and mitigation actions at Peterson Air Force Base in Colorado. During our visit to that installation, officials showed us the sites they are investigating—to include the current (see fig. 3 below) and former fire training areas—to determine the extent to which their prior use of firefighting foam may have contributed to the discovery of PFOS and PFOA in the drinking water of three nearby communities. Additionally, the Air Force has awarded a contract for, among other things, installing treatment systems in those communities. In another example, the Air Force reported spending about $800,000 on environmental investigations at Joint Base Langley-Eustis in Virginia, but nothing yet on mitigation actions. During our visit to this installation, officials told us that they had not taken any mitigation actions because they do not use the installation’s groundwater as a drinking water source; the utility that serves the installation, as well as the nearby city of Newport News, obtains its drinking water primarily from a surface water source, which officials said was approximately 20 miles from the installation. The Navy identified 127 installations with known or suspected releases of PFOS and PFOA, spent about $20.5 million on environmental investigations at 47 of those installations, and spent about $24 million on mitigation actions at or near 5 of those installations. For example, the Navy reported spending about $15 million on environmental investigations and mitigation actions at the former Naval Air Station Joint Reserve Base Willow Grove in Pennsylvania. During our visit to this installation, officials told us that the Navy is investigating the extent to which PFOS and PFOA on the installation may have contaminated a nearby town’s drinking water. The Navy has agreed to fund installation of treatment systems and connections of private well owners to the town’s drinking water system, among other things. In another example, the Navy reported spending nearly $3 million on environmental investigations and mitigation actions at Naval Auxiliary Landing Field Fentress in Virginia. During our visit to this installation, officials told us that the Navy is providing bottled water to the approximately 20 to 30 personnel who work there and plans to install a treatment system to treat for PFOS and PFOA. The Army identified 61 installations with known or suspected releases of PFOS and PFOA, spent about $1.6 million on environmental investigations at 13 of those installations, and has not yet begun any mitigation actions at or near the identified installations. For example, the Army reported spending about $26,000 on environmental investigations at Fort Carson in Colorado, but nothing yet on mitigation actions. During our visit to this installation, officials told us that they had found PFOS and PFOA in groundwater near their previous fire training area but that the installation does not use that groundwater as a drinking water source, and state officials told us that it is unlikely that PFOS and PFOA from Fort Carson had affected any nearby drinking water sources. According to DOD, it may take several years for the department to determine how much it will cost to cleanup PFOS and PFOA contamination at or near its military installations. In January 2017, we reported that DOD had not notified Congress that the costs for environmental cleanup at closed installations will significantly increase due to the high cost of remediating emerging contaminants—including PFOS and PFOA. We also reported that DOD officials had not determined the total costs for cleaning up emerging contaminants at closed installations. We recommended that DOD include in future annual reports to Congress best estimates of the environmental cleanup costs for emerging contaminants as additional information becomes available, and DOD concurred with the recommendation and stated its commitment to do so. DOD previously directed installations to test for perchlorate in drinking water. Following the EPA’s issuance of an interim drinking water health advisory for perchlorate in 2008, DOD issued policy in April 2009—which superseded similar policy that was issued in January 2006—directing DOD-owned drinking water systems that were testing for inorganic substances to also test for perchlorate. Installations that found perchlorate in their drinking water were to consult with their leadership on appropriate actions to take and to continue testing on a quarterly basis until they determined that perchlorate levels were likely to remain below EPA’s health advisory level, or any applicable federal or state regulation. Citing congressional and regulatory agency concerns related to perchlorate, DOD developed a database for storing the results of perchlorate testing. According to ASD (EI&E), the database was last updated in 2009 and is no longer being used by the department. ASD (EI&E) officials stated that they are no longer regularly testing drinking water for perchlorate unless there is a state requirement to do so; previous testing indicated that DOD was not a primary source of perchlorate in drinking water and that known releases of perchlorate did not currently pose a threat to drinking water. According to EPA, the agency expects to issue a final drinking water regulation for perchlorate by the end of 2019. ASD (EI&E) officials told us that, once EPA has issued a final regulation, DOD is committed to complying with it. During the period we reviewed, DOD data indicate that DOD public water systems complied with EPA and state health-based drinking water regulations at a level comparable with other systems in the United States. However, we found that the military departments did not report all violations of these regulations to ASD (EI&E) during that period, which illustrates that DOD’s internal reporting requirements for drinking water data are either not clear in DOD regulations or are not clearly understood by those implementing them. Unless ASD (EI&E) and the military departments act to make any necessary clarifications to and increase understanding of DOD’s annual reporting requirements, ASD (EI&E) may not have complete data to effectively oversee the military departments’ compliance with drinking water regulations. Further, the data indicated that systems providing DOD-treated drinking water had more reported health-based violations than DOD systems providing non-DOD-treated drinking water. However, DOD has not used these data to identify the reasons that these differences may exist. Without using available data to identify why differences in violations appear to exist between DOD’s two types of public water systems, DOD will likely be hampered in its ability to identify what actions, if any, could be taken to address any differences and improve overall compliance with health-based drinking water regulations. We are making a total of five recommendations to DOD. The Assistant Secretary of Defense for Energy, Installations, and Environment, in consultation with the Secretaries of the military departments, should identify and implement any necessary changes to DOD’s environmental compliance policy to clarify DOD’s reporting requirements for violations of health-based drinking water regulations. (Recommendation 1) The Secretary of the Army should identify and implement actions to increase understanding at Army installations and commands about DOD’s reporting requirements for violations of health-based drinking water regulations. These actions may include improved communication to or additional training for personnel. (Recommendation 2) The Secretary of the Navy should identify and implement actions to increase understanding at Navy installations and commands about DOD’s reporting requirements for violations of health-based drinking water regulations. These actions may include improved communication to or additional training for personnel. (Recommendation 3) The Secretary of the Air Force should identify and implement actions to increase understanding at Air Force installations and commands about DOD’s reporting requirements for violations of health-based drinking water regulations. These actions may include improved communication to or additional training for personnel. (Recommendation 4) The Assistant Secretary of Defense for Energy, Installations, and Environment, in consultation with the Secretaries of the military departments, should (a) review reported compliance data to identify the reasons for any differences in the number of violations of health-based drinking water regulations between DOD’s two types of public water systems and (b) identify and implement any actions needed to address the causes of any differences in the number of violations between DOD’s two types of public water systems. (Recommendation 5) We provided a draft of this report to DOD and EPA for review and comment. In its written comments, reproduced in appendix III, DOD concurred with our recommendations. DOD and EPA also provided technical comments, which we incorporated as appropriate. Based on technical comments from DOD, we revised the title of the report to more clearly specify the actions DOD should take to address the findings in our report. We are sending copies of this report to the appropriate congressional committees; the Secretary of Defense; the Assistant Secretary of Defense for Energy, Installations, and Environment; the Secretaries of the Army, the Navy, and the Air Force; and the Administrator of EPA. In addition, the report is available at no charge on the GAO website at http://www.gao.gov. If you or your staff have any questions about this report, please contact us at J. Alfredo Gómez, (202) 512-3841 or gomezj@gao.gov, or Brian J. Lepore, (202) 512-4523 or leporeb@gao.gov. Contact points for our Offices of Congressional Relations and Public Affairs may be found on the last page of this report. GAO staff who made key contributions to this report are listed in appendix IV. Senate Report 114-255 accompanying a bill for the national defense authorization for fiscal year 2017 included a provision for us to review the Department of Defense’s (DOD) efforts to manage contaminants in drinking water. This report examines the extent to which DOD has (1) internally reported data on compliance with health-based drinking water regulations at military installations and used those data to assess compliance at its two types of public water systems and (2) taken actions to address concerns with its firefighting foam containing perfluorinated chemicals (PFCs) and to address elevated levels of perfluorooctanesulfonic acid (PFOS), perfluorooctanoic acid (PFOA), and perchlorate in drinking water at or near military installations. For objective one, we reviewed DOD’s policy on environmental compliance in the United States, which directs the military departments to annually report data to the Assistant Secretary of Defense for Energy, Installations, and Environment (ASD (EI&E)) on compliance with and violations of Environmental Protection Agency (EPA) and state health- based drinking water regulations at military installations. We analyzed data reported by the military departments to ASD (EI&E) on compliance with and violations of health-based drinking water regulations at DOD public water systems located at military installations in the United States for fiscal years 2013 through 2015, the most recent data available at the time of our review. We analyzed the data to identify (1) the number of people served by DOD public water systems that complied with applicable EPA and state health-based drinking water regulations during the fiscal year and (2) the number of people served by DOD public water systems that violated at least one of these regulations sometime during the fiscal year. We performed this analysis for both types of DOD public water systems—those that provide DOD-treated drinking water, and those that provide non-DOD-treated drinking water. We also used the data to identify the military installations where the reported violations occurred; the nature of the violation (including the contaminant involved); and the number of people affected. Next, we collected data from EPA’s Safe Drinking Water Information System for all public water systems in the United States. We used DOD-provided public water system identification numbers to identify in the EPA system any violations for health-based drinking water regulations at those DOD systems for fiscal years 2013 through 2015. We then compared the violations found in EPA’s data to the data reported by the military departments to ASD (EI&E) to determine the extent to which the military departments were reporting all violations of health-based drinking water regulations to ASD (EI&E). We also analyzed DOD’s data to identify any differences in violations between DOD- and non-DOD-treated drinking water. We evaluated the military departments’ reported data and DOD’s use of these data to determine compliance with DOD’s reporting requirements in the department’s environmental compliance instruction and Standards for Internal Control in the Federal Government. According to these standards, quality information is needed to achieve an organization’s objectives, management is to monitor performance over time and promptly resolve any findings, and actions such as improved communication to and additional training for personnel are helpful for an organization to meet its objectives. We also discussed our analysis with ASD (EI&E) and military department officials, and discussed possible reasons for why any violations went unreported to ASD (EI&E) and why there may be differences in violations between DOD- and non-DOD- treated drinking water. We assessed the reliability of the DOD and EPA data on violations of health-based drinking water regulations by reviewing relevant documentation, testing the data for obvious errors, and interviewing knowledgeable officials. As we have previously found, EPA’s data system may not contain all public water violations as states have under-reported the violations. During this review, we found that some public water system identification numbers for DOD installations could not be matched with EPA’s system and, therefore, were excluded from our analysis. As a result, some DOD installation violations may be missing from the data, and we may not have comprehensive violations data for health-based drinking water regulations at DOD installations. Nonetheless, we determined that DOD and EPA data were sufficiently reliable for the purpose of identifying whether any drinking water violations were recorded in EPA’s system but not internally reported within DOD, and to indicate possible differences in drinking water violations, as reported by the military departments, between DOD’s two types of public water systems. For objective two, we reviewed policies issued by the military departments on the use of firefighting foam that contains PFCs. We also reviewed DOD documents related to research into PFC-free firefighting foams that can meet the department’s performance and compatibility requirements, as well as DOD’s military specification document that outlines those requirements. We met with officials from ASD (EI&E) and the military departments to discuss their policies on the use of firefighting foam and actions taken to address concerns with the use of firefighting foam containing PFCs, including the future use of firefighting foam. Additionally, we met with Navy officials responsible for testing existing firefighting foam products and setting the military specifications for firefighting foam use in DOD. Additionally, we obtained and reviewed four regulatory administrative orders—three from EPA and one from the Ohio Environmental Protection Agency—directing DOD to address elevated levels of PFOS and PFOA contamination in drinking water at or near four active and closed military installations, and reviewed documentation related to DOD’s efforts to address these administrative orders. We also met with officials from Ohio and the EPA regions that issued the orders—EPA Regions 1 and 3—as well as DOD officials who responded to the orders, to discuss DOD’s response to the orders. We reviewed drinking water guidance issued by ASD (EI&E) and the military departments on testing installation drinking water for PFOS and PFOA and responding to known or suspected releases of PFOS and PFOA. We analyzed DOD-provided data on the installations where DOD-conducted testing showed the presence of PFOS and PFOA in drinking water above the EPA’s health advisory level for those contaminants (as of March 2017) and on the costs and actions taken to investigate and mitigate PFOS and PFOA at or near military installations (as of December 2016). We assessed the reliability of the data by examining the data for obvious errors and inconsistencies, comparing the data, where applicable, with other information collected, and by interviewing knowledgeable officials; we found the data to be sufficiently reliable for our purposes of describing what DOD has reported on its actions and costs for responding to PFOS and PFOA. Additionally, we reviewed DOD policy and our prior work on testing for and responding to perchlorate at military installations. We met with ASD (EI&E) and military department officials to discuss DOD actions to address PFOS, PFOA, and perchlorate. To obtain additional information on DOD actions to address emerging contaminants in drinking water, we conducted site visits to a nongeneralizable sample of seven current and former military installations—at least two installations per military department—that were selected because they were investigating or responding to unregulated DOD-identified emerging contaminants in drinking water; these installations are listed below. We also met with EPA and state regulatory officials to better understand how DOD was responding to administrative orders and addressing PFOS, PFOA, and perchlorate at or near DOD installations. Specifically, we met with officials from selected EPA regions and state regulatory offices that had issued an administrative order for PFOS and PFOA or whose region or state included the installations we visited; those EPA regions and states are listed below. We also compared DOD’s list of emerging contaminants with EPA documentation to determine how many DOD-identified emerging contaminants (1) have been regulated by EPA under the Safe Drinking Water Act or (2) are currently unregulated but have an EPA-issued drinking water health advisory. We visited or contacted the following offices and locations during our review. Unless otherwise specified, these organizations are located in or near Washington, D.C. Office of the Secretary of Defense Office of the Assistant Secretary of Defense for Energy, Installations, Office of the Deputy Assistant Secretary of Defense for Environment, Safety, and Occupational Health Office of the Assistant Chief of Staff of the Army for Installation U.S. Army Installations Management Command, Fort Sam Houston, U.S. Army Environmental Command, Fort Sam Houston, Texas Fort Carson, Colorado Fort Jackson, South Carolina Office of the Assistant Secretary of the Navy for Energy, Installations, Office of the Chief of Naval Operations, Energy and Environmental Commander, Navy Installations Command Marine Corps Installations Command Naval Facilities Engineering Command Naval Sea Systems Command Former Naval Air Station Joint Reserve Base Willow Grove, Naval Auxiliary Landing Field Fentress, Virginia Department of the Air Force Office of the Assistant Secretary of the Air Force for Installations, Air Force Civil Engineer Center, Joint Base San Antonio, Texas Former Pease Air Force Base, New Hampshire Joint Base Langley-Eustis, Virginia Peterson Air Force Base, Colorado Wright-Patterson Air Force Base, Ohio Office of Research and Development Office of Land and Emergency Management Office of Enforcement and Compliance Assurance EPA Region 1, Boston, Massachusetts EPA Region 3, Philadelphia, Pennsylvania EPA Region 4, Atlanta, Georgia EPA Region 5, Chicago, Illinois EPA Region 8, Denver, Colorado EPA Region 9, San Francisco, California Colorado Department of Public Health and Environment Ohio Environmental Protection Agency Pennsylvania Department of Environmental Protection South Carolina Department of Health and Environmental Control We conducted this performance audit from June 2016 to October 2017 in accordance with generally accepted government auditing standards. Those standards require that we plan and perform the audit to obtain sufficient, appropriate evidence to provide a reasonable basis for our findings and conclusions based on our audit objectives. We believe that the evidence obtained provides a reasonable basis for our findings and conclusions based on our audit objectives. The Department of Defense’s (DOD) list of emerging contaminants includes 21 contaminants that can be found in drinking water: 10 that have been regulated by the Environmental Protection Agency (EPA) under the Safe Drinking Water Act and 11 that are currently unregulated but have an EPA-issued drinking water health advisory. Table 4 shows the regulatory status for each of the 21 contaminants. In addition to the contacts named above, Maria Storts (Assistant Director), Diane B. Raynes (Assistant Director), Kazue Chinen, Michele Fejfar, Jennifer Gould, Karen Howard, Richard P. Johnson, Mae Jones, Daniel Kuhn, Summer Lingard-Smith, Daniel Longo, Felicia Lopez, Geoffrey Peck, Ophelia Robinson, Jerry Sandau, and Sara Sullivan made key contributions to this report.

Summary: According to DOD, about 3 million people in the United States receive drinking water from DOD public water systems, which are to comply with EPA and state health-based regulations. EPA and DOD have detected elevated levels of two unregulated, DOD-identified emerging contaminants found in firefighting foam—PFOS and PFOA—in drinking water at or near installations. Perchlorate, an unregulated chemical used by DOD in rocket fuel, can also be found in drinking water. The Senate Report accompanying a bill for national defense authorization for fiscal year 2017 included a provision for GAO to review DOD management of drinking water contaminants. This report examines the extent to which DOD has (1) internally reported data on compliance with health-based drinking water regulations at military installations and used those data to assess compliance at its two types of public water systems, and (2) taken actions to address concerns with its firefighting foam and elevated levels of PFOS, PFOA, and perchlorate in drinking water at or near military installations. GAO reviewed DOD guidance and EPA drinking water regulations, advisories, and orders; analyzed DOD and EPA drinking water data; and visited seven installations from among those addressing emerging contaminants in drinking water. The Department of Defense (DOD) has not internally reported all data on compliance with health-based drinking water regulations or used available data to assess compliance. DOD data for fiscal years 2013-2015 indicate that DOD public water systems complied with Environmental Protection Agency (EPA) and state health-based drinking water regulations at levels comparable with other systems in the United States. However, the military departments did not report all violations to DOD, i.e., while 77 installations reported violations to DOD, GAO found that at least 16 additional installations did not. Until DOD takes steps to increase the clarity and understanding of its internal reporting requirements, it may not have the data it needs to fully oversee compliance. DOD also has not used its data to determine why its two types of systems—one that provides DOD-treated water and another that provides non-DOD-treated water—have different compliance rates. Specifically, DOD's data indicate that about 99 percent of the people who received non-DOD-treated drinking water were served by systems with no violations, while about 89 percent of the people who received DOD-treated drinking water were served by systems with no violations. Absent further analysis of its data, DOD may not be able to improve overall compliance. DOD has initiated actions to address concerns with both its firefighting foam and also with elevated levels in drinking water of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and perchlorate, which are DOD-identified emerging contaminants. PFOS and PFOA can be found in DOD's firefighting foam. DOD has restricted its use of this foam and is funding efforts to develop a new foam that meets DOD performance requirements. Additionally, at 11 military installations (see fig.), DOD has shut down wells, provided alternate water sources, or installed water treatment systems to respond to elevated levels of PFOS and PFOA, at times in response to EPA and state orders. GAO is making five recommendations to improve DOD's reporting and use of data on compliance with health-based drinking water regulations. DOD concurred with the recommendations.