According to our analysis of EPA documents, DOD’s list  includes 21 contaminants that can be found in drinking water. The other 28  DOD-identified emerging contaminants do not have EPA drinking water  regulations or health advisories. DOD Has Not Internally Reported All Data on Compliance with Drinking Water Regulations or Used Available Data to Evaluate Differences between Its Drinking Water Systems

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. DOD Has Not Used Available Data to Assess Why DOD-Treated Water Appears to Have More Health-Based Violations Than Non-DOD-Treated Drinking Water

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. DOD Has Initiated Actions to Address Concerns with Its Firefighting Foam as Well as Elevated Levels of PFOS, PFOA, and Perchlorate in Drinking Water

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. Conclusions

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. Recommendations for Executive Action

We are making a total of five recommendations to DOD. In its written comments, reproduced in appendix III, DOD  concurred with our recommendations. Appendix I: Objectives, Scope, and Methodology

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. We also analyzed DOD’s data to identify any differences in violations  between DOD- and non-DOD-treated drinking water. 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.
Why GAO Did This Study

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.

What GAO Found

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.

What GAO Recommends

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.