Perchlorate: Occurrence Is Widespread but at Varying Levels; Federal Agencies Have Taken Some Actions to Respond to and Lessen Releases
Published: 2010-08-12T00:00:00

Fast Facts:

Highlights:
section_title: Why GAO Did This Study
paragraphs: Perchlorate is both a man-made and naturally occurring chemical. It is used in rocket fuel, explosives, fireworks, and other products. Naturally occurring perchlorate is produced through atmospheric processes and then settles on surface water or land. Perchlorate can disrupt the uptake of iodide in the thyroid, potentially interfering with thyroid function and negatively affecting fetal and infant brain development and growth. As of June 2010, there is no federal regulatory standard for perchlorate in drinking water, and the Environmental Protection Agency (EPA), which has the authority to regulate contaminants in public drinking water systems, had not determined whether to establish one. The Department of Defense (DOD), the National Aeronautics and Space Administration (NASA), and the Department of Energy (DOE) are the primary federal users of perchlorate. GAO was asked to examine (1) what is known about the extent to which perchlorate occurs in the nation's water and food supply and its likely sources; (2) what actions DOD, NASA, and DOE have taken to respond to or lessen perchlorate releases; and (3) what actions states, such as California and Massachusetts, have taken to regulate perchlorate. To address these questions, GAO analyzed data from EPA, DOD, NASA, and DOE, reviewed agency documents, and interviewed federal and state officials, researchers, and others.
section_title: What GAO Found
paragraphs: Perchlorate has been found in water and other media at varying levels in 45 states, as well as in the food supply, and comes from a variety of sources. EPA conducted one nationwide perchlorate sampling, between 2001 and 2005, and detected perchlorate at or above 4 parts per billion in 160 of the 3,865 public water systems tested (about 4.1 percent). In 31 of these 160 systems, perchlorate was found above 15 parts per billion, EPA's current interim health advisory level. Sampling by DOD, NASA, and DOE detected perchlorate in drinking water, groundwater, surface water, soil, and sediment at some facilities. For example, GAO's analysis of DOD data showed that perchlorate was detected at almost 70 percent of the 407 installations sampled from fiscal years 1997 through 2009, with detections ranging from less than 1 part per billion to 2.6 million parts per billion. A 2006 Food and Drug Administration study found perchlorate in 74 percent of 285 food items tested, with certain foods, such as tomatoes and spinach, having higher perchlorate levels than others. According to researchers, concentrations of perchlorate at or above 100 parts per billion generally result from activities involving man-made perchlorate, such as the use of perchlorate as a rocket propellant. Lower concentrations can result from the use of man-made perchlorate, atmospheric processes, or the use of fertilizer containing naturally occurring perchlorate. According to DOD, NASA, and DOE officials, the agencies have sampled, monitored and, at several sites, begun cleaning up perchlorate. When DOD detects perchlorate at or above threshold levels--currently 15 parts per billion for water--DOD is to investigate further and may take additional actions. DOD has taken actions beyond initial sampling at 48 of the 53 installations with perchlorate detections above 15 parts per billion. NASA is in the midst of a cleanup at the Jet Propulsion Laboratory in California and is monitoring the level of perchlorate in groundwater at three other facilities. In addition, DOE is cleaning up perchlorate at two facilities involved in high explosives research, development, and testing and is monitoring the level of perchlorate in groundwater at two other facilities. According to DOD, NASA, and DOE officials, the perchlorate detected at their facilities is largely the result of past disposal practices. Officials at these agencies told us that by complying with current federal and state waste disposal laws and regulations, they have lessened their perchlorate releases. In addition, DOD is developing perchlorate substitutes for use in weapons simulators, flares, and rockets. In the absence of a federal regulatory standard for perchlorate in drinking water, California and Massachusetts have adopted their own standards. California adopted a drinking water standard of 6 parts per billion in 2007, and Massachusetts set a drinking water standard of 2 parts per billion in 2006. The key benefits of a regulatory standard cited by state officials include protecting public health and facilitating cleanup enforcement. However, limited information exists on the actual costs of regulating perchlorate in these states. Also, at least 10 other states have established guidance levels for perchlorate in drinking water (ranging from 1 to 18 parts per billion) or in groundwater. This report contains no recommendations.

section_title: Letter
paragraphs: Perchlorate is both a man-made and naturally occurring chemical. It is  manufactured for use as an oxidizer in solid rocket fuel, munitions,  explosives, fireworks, road flares, and other products. It also occurs  naturally and is found in certain fertilizers. Perchlorate can disrupt the  uptake of iodide in the thyroid, potentially interfering with thyroid  function and negatively affecting fetal and infant brain development and  growth. Because of concerns over these and other potential health  impacts, some states, water utilities, and Members of Congress have urged  the U.S. Environmental Protection Agency (EPA) to set a federal drinking  water standard for perchlorate. The Department of Defense (DOD), the  National Aeronautics and Space Administration (NASA), and the  Department of Energy (DOE) are the primary federal users of perchlorate.
In response to your request for information on perchlorate, this report  examines (1) what is known about the extent to which perchlorate occurs  in the nation’s water and food supply and its likely sources; (2) what  actions DOD, NASA, and DOE have taken to respond to or lessen  perchlorate releases; and (3) what actions states, such as California and  Massachusetts, have taken to regulate perchlorate. To determine what is  known about the extent of perchlorate occurrence in the nation’s water  and food supply and its likely sources, we analyzed perchlorate  occurrence data provided by EPA, DOD, NASA, and DOE and interviewed  federal and state agency officials, researchers, industry representatives,  and others. To determine what actions DOD, NASA, and DOE have taken  to respond to or lessen perchlorate releases, we analyzed agency data,  reviewed agency documents, and interviewed agency officials and federal  and state environmental officials. We visited selected DOD and NASA  facilities to discuss and observe their activities related to perchlorate  cleanup, including Edwards Air Force Base (DOD), Redstone Army  Arsenal (DOD), the Jet Propulsion Laboratory (NASA), and the Marshall  Space Flight Center (NASA). We selected sites identified by EPA, DOD,  and NASA officials as illustrative of their perchlorate response actions. To  determine what actions California and Massachusetts have taken to  regulate perchlorate, we reviewed state documents and interviewed state  officials. In addition, we reviewed documents and interviewed officials in  states that have set advisory levels and public health goals for perchlorate.  We also interviewed EPA regional officials about state actions related to  perchlorate.
We assessed the reliability of the DOD data that we used by electronically  testing for obvious errors in accuracy and completeness, reviewing  information about the data and the systems that produced them, and  interviewing agency officials knowledgeable about the data. When we  found inconsistencies in the data, we worked with DOD officials to clarify  them before conducting our analyses. We also assessed the procedure  used to collect the EPA data we used. We determined that both the DOD  and EPA data were sufficiently reliable for the purposes of this report. We  conducted our work from July 2009 to August 2010 in accordance with all  sections of GAO’s Quality Assurance Framework that are relevant to our  objectives. The framework requires that we plan and perform the  engagement to obtain sufficient and appropriate evidence to meet our  stated objectives and to discuss any limitations in our work. We believe  that the information and data obtained, and the analysis conducted,  provide a reasonable basis for any findings and conclusions in this  product. See appendix I for a more detailed description of our objectives,  scope, and methodology.
subsections: section_title: Background
paragraphs: Man-made perchlorate is primarily produced as ammonium perchlorate  for use as an oxidizer in solid rocket fuels, fireworks, explosives, and road  flares. Perchlorate can also be present as an ingredient or as an impurity in  such items as matches, lubricating oils, aluminum refining, rubber  manufacturing, paint and enamel manufacturing, and leather tanning and  as an ingredient in bleaching powder used for paper and pulp processing.  Further, perchlorate can develop as a by-product of sodium hypochlorite  (i.e., bleach) solutions used as disinfectant in water and wastewater  treatment plants when these solutions are stored for a long period of time.  Naturally occurring perchlorate is produced through atmospheric  processes and then settles on surface water or land as precipitation or dry  deposits. Perchlorate also exists as a natural impurity in nitrate salts from  Chile, which are imported and used to produce nitrate fertilizers and other  products.
EPA has the authority to regulate contaminants, such as perchlorate, in  public drinking water systems. Under the Safe Drinking Water Act, as  amended, when EPA decides to regulate a contaminant, its determination  must be based on findings that (1) the contaminant may have an adverse  health effect, (2) the contaminant is known to occur or there is substantial  likelihood that the contaminant will occur in public water systems with a  frequency and at levels of public health concern, and (3) in the sole  judgment of the Administrator, regulation of the contaminant presents a  meaningful opportunity for reducing health risks for persons served by  public water systems.
subsections: section_title: History of EPA’s Investigation and Study of Perchlorate
paragraphs: Perchlorate was initially identified by EPA as a potential contaminant in  1985, when it was found in wells at hazardous waste sites in California. In  1992, EPA issued a provisional reference dose for perchlorate equivalent  to a concentration of 4 parts per billion in drinking water and, in 1995,  issued a revised provisional reference dose with a drinking water  equivalent ranging from 4 to 18 parts per billion. These reference doses  were considered provisional by EPA because they had not undergone  internal or external peer review. However, EPA and state regulators could  use them to establish guidance levels for cleaning up contaminated  groundwater. A more sensitive perchlorate detection method became  available in 1997, and more states began detecting perchlorate in drinking  water, groundwater, and surface water.
In 1998, EPA published its first draft assessment of perchlorate exposure  health risks and placed perchlorate on its Contaminant Candidate List—a  list of contaminants that may require regulation under the Safe Drinking  Water Act. In 1999, under Unregulated Contaminant Monitoring Rule 1  (UCMR 1), EPA required all public drinking water systems serving more  than 10,000 people and 800 representative public water systems serving  10,000 or fewer people to monitor their drinking water systems for  perchlorate over a 12-month period and to report the results. Also, in  1999, an external panel of independent scientists reviewed EPA’s draft risk  assessment and recommended additional studies and analyses to provide  more data on perchlorate and its health effects. DOD and industry  researchers conducted such studies and submitted them to EPA. Based on  an analysis of these studies, EPA revised its draft perchlorate risk  assessment and released it for peer review and public comment in January  2002. The revised draft risk assessment included a proposed reference  dose equivalent to a concentration of 1 part per billion in drinking water.  DOD, industry, and some members of the scientific community disagreed  with EPA’s draft risk assessment and its conclusions, including the  proposed reference dose. The scientific controversy involved, among  other things, the adequacy and relevance of available human data for  assessing health risks, the quality and validity of some animal data, the  definition of adverse health effect, and the application of uncertainty  factors.
After a second peer review, and in light of the criticisms from some  scientists surrounding the concentration at which perchlorate presents a  human health risk, DOD, NASA, DOE, and EPA asked the National  Academy of Sciences, in 2003, to review the available science and EPA’s  draft health risk assessment. In January 2005, the Academy’s National  Research Council (NRC) recommended a reference dose for perchlorate  exposure of 0.0007 milligrams per kilogram of body weight per day. EPA  calculated the drinking water equivalent of this dose to be 24.5 parts per  billion. EPA adopted the reference dose and, in January 2006, directed its  regional offices to use 24.5 parts per billion as a preliminary remediation  goal when assessing sites for cleanup under the Comprehensive  Environmental Response, Compensation, and Liability Act (CERCLA) of  1980 and the National Oil and Hazardous Substances Pollution  Contingency Plan, the regulation that implements CERCLA.
In October 2008, EPA issued a preliminary determination not to regulate  perchlorate and requested public comment on its findings that perchlorate  occurs infrequently at levels of health concern in public water systems and  that there was not a “meaningful opportunity for health risk reduction”  through a national drinking water regulation. In response to stakeholder  comments that provided additional scientific evaluation of the information  EPA used to make its preliminary determination, EPA announced, in  January 2009, that it planned to seek additional input from NRC on  assumptions regarding the possible effects of perchlorate on infants and  young children. Around the same time, EPA’s Office of Water published an  interim health advisory for perchlorate that includes a health advisory  level of 15 parts per billion. This interim health advisory level takes into  account exposure from food, as well as drinking water, for pregnant  women and their fetuses (the most sensitive life stage identified by NRC).  The advisory provides informal technical guidance to assist state and local  officials in protecting public health where perchlorate contamination of  drinking water has occurred, while EPA evaluates the opportunity to  reduce risks through a national drinking water standard. Following the  establishment of the interim health advisory, EPA’s Office of Solid Waste  and Emergency Response withdrew its preliminary remediation goal for  perchlorate of 24.5 parts per billion. In its place, EPA recommended the  interim health advisory level of 15 parts per billion be used as the  preliminary remediation goal when assessing sites for cleanup under  CERCLA.
In August 2009, EPA published a notice that it would not seek additional  input from NRC and instead was seeking public comment on additional  approaches for interpreting the available data on the level of health  concern, the frequency of occurrence of perchlorate in drinking water, and  the opportunity for health risk reduction through a national drinking water  standard. In April 2010, EPA’s Office of Inspector General released a  report that reviewed and critiqued the risk assessment process and  procedures used by EPA to develop and derive the perchlorate reference  dose. As of July 2010, EPA had not yet made a final decision whether to  establish a regulatory standard for perchlorate in drinking water.
section_title: Requirements for Federal Agencies Related to Perchlorate
paragraphs: Several federal laws impose requirements on federal agencies related to  monitoring, reporting, and cleanup of hazardous substances, pollutants,  and contaminants such as perchlorate.
CERCLA, as amended, better known as Superfund, requires responsible  federal agencies to identify and assess releases of hazardous substances  such as perchlorate and to follow CERCLA requirements in their cleanup,  among other things. The CERCLA process typically follows a series of  steps, which may include investigations, human health risk assessments  and ecological risk assessments, evaluation and selection of cleanup  approaches, and implementation of the cleanup, known as a remedial  action.
CERCLA itself does not establish cleanup standards. Rather, the remedial  action chosen by a federal agency must meet applicable or relevant and  appropriate requirements based on standards for contaminants set under  state or federal laws or regulations and in consideration of other  guidance. If there is no such requirement for a given contaminant, the  agency must still achieve a degree of cleanup, which, at a minimum,  assures protection of human health and the environment. Both existing  and potential sources of drinking water are generally to be considered in  assessing risk and in selecting a remedy.
In general, EPA is the lead regulator for all sites on EPA’s list of some of  the most contaminated sites in the country—the National Priorities List— which are commonly referred to as Superfund sites. State environmental  agencies may be the lead regulator at other sites.
Executive Order 12580 delegated certain CERCLA response authorities to  federal agencies. In particular, DOD and DOE each have lead response  agency authority for properties under their respective jurisdictions, which  they are to exercise consistent with CERCLA section 120 governing  federal facilities.
The Superfund Amendments and Reauthorization Act established the  Defense Environmental Restoration Program in 1986 and directs DOD to  clean up releases of hazardous substances, such as perchlorate, at active  DOD installations and formerly used defense sites in accordance with  CERCLA.
The Resource Conservation and Recovery Act (RCRA), as amended,  requires federal agencies generating, treating, or disposing of hazardous  wastes, including hazardous wastes containing perchlorate, to obtain  permits and/or to comply with regulations applicable to the management  of such wastes.
Pursuant to its responsibilities under the Safe Drinking Water Act, in 1999,  EPA promulgated the UCMR 1, which required entities, including federal  agencies, operating large and selected small public water supplies to  monitor their drinking water systems for perchlorate and other  contaminants over a 1-year period and to report the results.
The Clean Water Act requires federal agencies discharging pollutants into  surface waters—such as from a wastewater treatment facility—to obtain a  National Pollutant Discharge Elimination System permit from EPA and  comply with its discharge limitations.
Pursuant to RCRA and the Safe Drinking Water Act, EPA can issue  perchlorate abatement orders to federal facilities where there is an  imminent and substantial endangerment to health and other conditions are  met.
Since 2002, DOD has issued a series of perchlorate policies. Most recently,  in April 2009, DOD issued a policy on perchlorate release management that  directs the military services to, among other things, address perchlorate in  the same manner that the services address other contaminants of concern.  The policy adopts EPA’s preliminary remediation goal for perchlorate of  15 parts per billion in water where (1) there is an actual or potential  drinking water exposure pathway and (2) no legally applicable or  relevant and appropriate requirements exist under federal or state laws.  NASA and DOE have issued no policies that focus exclusively on  perchlorate, according to agency officials.
section_title: Perchlorate Occurs Nationwide at Varying Levels, and the Sources Are Sometimes Difficult to Determine
paragraphs: The full extent of perchlorate occurrence is unknown because there is no  national system to track detections. However, perchlorate has been found  at varying levels across the nation in water and the food supply and is  known to come from a variety of sources. While the sources of perchlorate  at or above 100 parts per billion in the environment are generally the result  of defense-related or manufacturing activities, sources of concentrations  below that level can be difficult to determine.
subsections: section_title: Although the Full Extent of Perchlorate Occurrence Is Unknown, It Has Been Detected at Varying Levels in Drinking Water and Other Media in 45 States
paragraphs: There is no national system to track perchlorate detections, so the full  extent of perchlorate occurrence nationwide is unknown. In 2005, we  recommended that EPA establish a formal structure to centrally track and  monitor perchlorate detections. EPA officials disagreed with our  recommendation, saying that the agency already had sufficient  information on perchlorate concentrations in various environmental media  that indicated the extent of contamination nationally and that if EPA were  to implement a tracking system, the agency would require additional  resources. However, as our report noted, without a formal system to track  and monitor perchlorate findings and cleanup activities, EPA and the  states do not have the most current and complete accounting of  perchlorate as an emerging contaminant of concern, including the extent  of perchlorate found and the extent or effectiveness of cleanup projects.
Although there has been no nationwide sampling for perchlorate recently,  nationwide sampling under EPA’s UCMR 1, which occurred between 2001  and 2005, detected perchlorate at or above 4 parts per billion in at least  one sample in approximately 4.1 percent of the public drinking water  systems tested. According to EPA data, perchlorate was reported in 160 of  3,865 public drinking water systems, with detections ranging from 4 to 420  parts per billion. Thirty-one of the 160 systems, or about a fifth, had  detections above 15 parts per billion—EPA’s current interim drinking  water health advisory level. Figure 1 shows the number of public water  systems with perchlorate detections and the maximum concentration  detected, according to EPA’s data.
EPA and U.S. Geological Survey officials and other researchers told us  that technology is now available to detect perchlorate at levels below 1  part per billion, while the analytical method used under UCMR 1 had a  minimum detection level of 4 parts per billion.
Sampling conducted at various times by federal agencies, including DOD,  NASA, DOE, and EPA, has detected perchlorate in drinking water,  groundwater, surface water, soil, and sediment. Specifically,    DOD reported perchlorate detections at 284 of its installations, or almost  70 percent of the 407 installations sampled from fiscal years 1997 through  2009, with detections ranging from less than 1 part per billion to 2.6 million  parts per billion. Maximum detection in parts per billion included 30 in  drinking water, 230 in sediment, 6,600 in surface water, 786,000 in soil, and  2,600,000 in groundwater. Fifty-three of the 284 installations, or about 20  percent, reported perchlorate concentrations above 15 parts per billion,  DOD’s current screening threshold for initiating additional site  investigation when perchlorate is detected in water. According to DOD,  the agency generally uses perchlorate in munitions and missiles, and its  releases of perchlorate occurred primarily at maintenance facilities, rocket  testing sites, and waste disposal areas.
NASA found perchlorate at four of the seven facilities where it sampled for  the chemical from fiscal years 1997 through 2009. According to NASA, the  agency began to look for perchlorate at its facilities across the country  after a more sensitive method of perchlorate detection became available in  the late 1990s and in response to requests from federal and state  regulators. NASA reported the highest detection of 13,300 parts per billion  in groundwater in 2002 at the Jet Propulsion Laboratory in California. At  the Marshall Space Flight Center in Alabama, perchlorate detections from  2000 through 2008 fell at or below 4.4 parts per billion in groundwater.  According to NASA, at the Stennis Space Center in Mississippi, in 2003, the  agency detected perchlorate concentrations ranging from 3.7 to 12,639  parts per billion in groundwater. At the White Sands Test Facility in New  Mexico, perchlorate detections from 2006 through 2009 fell at or below 2.6  parts per billion in groundwater. At the Jet Propulsion Laboratory, NASA  attributed perchlorate contamination to the disposal of perchlorate waste  in underground pits during the 1940s and 1950s. According to NASA,  perchlorate contamination at Stennis is associated with munitions testing.
DOE detected perchlorate at the five facilities where it sampled for the  chemical in fiscal years 1998 through 2009—Lawrence Livermore National  Laboratory Site 300 in California, Los Alamos National Laboratory in New  Mexico, the Pantex Plant in Texas, Sandia National Laboratories in New  Mexico, and the Energy Technology Engineering Center at the Santa  Susana Field Laboratory in California. Detections occurred in  groundwater or soil and ranged from less than 1 part per billon to 3,090  parts per billion. DOE reported the highest concentrations (3,090 parts per  billion) in perched groundwater at the Pantex Plant. According to DOE,  perchlorate contamination resulted from historical waste management  practices and testing of high explosives.
As of June 2010, EPA reported perchlorate detections at 40 sites on the  National Priorities List. In addition to 25 sites maintained by DOD, NASA,  DOE, and the U.S. Department of the Interior, there were 15 private sites.  At private sites, the highest perchlorate levels ranged from 13 to 682,000  parts per billion in groundwater. See appendix II for a list of National  Priorities List sites where perchlorate has been identified as a contaminant  of concern.
Overall, considering detections reported by EPA and DOD, as shown in  figure 2, perchlorate has been detected in 45 states, the District of  Columbia, and three U.S. territories.
Two states, California and Massachusetts, mandate that public water  systems sample for perchlorate to ensure that public drinking water  supplies in their states comply with state drinking water standards (6 parts  per billion in California and 2 parts per billion in Massachusetts). Although  initial testing of drinking water systems found some levels of perchlorate  contamination, testing undertaken in fiscal year 2009 found no drinking  water systems that violated the standard in either state, according to state  officials. In California, according to state officials, they also track  perchlorate in groundwater because 40 percent of the state’s drinking  water supply comes from groundwater. California officials told us that  perchlorate occurrence is widespread in the state, with Southern  California having more detections at higher levels in groundwater than  other parts of the state. According to California officials, this perchlorate  came from a variety of sources including defense activities and Chilean  fertilizer. In Massachusetts, perchlorate levels at or above 2 parts per  billion have been found in only a few locations in groundwater and in one  surface water supply, according to state officials. However, many other  groundwater supplies have detected perchlorate at levels that are less than  2 parts per billion.
Additionally, research conducted in Arizona and northwest Texas detected  relatively low levels of perchlorate. In a 2004 report, the Arizona  Department of Environmental Quality, among others, assessed the extent  of perchlorate occurrence in the state’s water sources, including the  Colorado River, which is known to be contaminated with perchlorate from  a chemical plant near Henderson, Nevada. The study found that, while  perchlorate is present in certain areas of the state, the concentrations in  bodies of water not associated with industrial sites were generally at levels  well below 14 parts per billion, which was Arizona’s health-based guidance  level for perchlorate at the time. Also in 2004, Texas Tech University  reported on the source and distribution of perchlorate in northwest Texas  groundwater. The study found widespread perchlorate occurrences at  very low concentrations and concluded that they were likely the result of  natural processes and not caused by human activities.
From 2005 to 2007, the U.S. Geological Survey published several studies in  collaboration with other researchers investigating naturally occurring  perchlorate in groundwater, surface water, and soils in the United States.  In addition, a 2009 U.S. Geological Survey study found perchlorate from  Chilean fertilizer in Long Island, New York, and concluded that other areas  in the United States that used Chilean fertilizer in the late nineteenth  century through the twentieth century may also contain perchlorate. In  addition to the key studies cited above, smaller-scale studies have also  been conducted.
section_title: Food and Drug Administration and Other Researchers Have Found Perchlorate in a Variety of Foods at Low Concentrations
paragraphs: In addition to finding perchlorate in water and soil, Food and Drug  Administration (FDA) and other researchers have found perchlorate in a  variety of foods. Existing research suggests several ways that perchlorate  may enter the food supply, such as the use of perchlorate contaminated  water in agriculture. The most comprehensive study of perchlorate in  food—FDA’s 2006 Total Diet Study—found perchlorate in 74 percent of  the 285 food items tested across the country. These food items represent  the major components of the American diet, such as dairy, meat, fruits,  and vegetables. Certain foods, such as tomatoes and spinach, had higher  perchlorate levels than others. Using the analytical results for the food  samples collected, FDA researchers calculated and reported the estimated  average perchlorate intake from food for the total U.S. population and 14  age and gender subgroups. Estimated average perchlorate intake from  each food item varied by age and gender, but the average total  consumption of perchlorate for all groups was below the 2005 NRC- recommended reference dose for perchlorate exposure of 0.0007  milligrams per kilogram of body weight per day. The highest level of  average perchlorate consumption was reported for children 2 years of age,  with an estimated consumption ranging from 0.00035 to 0.00039 milligrams  per kilogram of body weight per day. According to the study, the average  level of perchlorate consumption for these children was higher because  they consume more food per their body weight, and they have different  food consumption patterns—with over half of their perchlorate intake  coming from dairy foods. According to an FDA official, in 2008, FDA  conducted another round of Total Diet Study sampling and is in the  process of compiling the data, though the FDA official we spoke with does  not expect results to be published until later in 2010 or 2011.
Other studies and researchers have found that certain foods are more  likely than others to contain perchlorate. For example, a 2009 study by  researchers at the Centers for Disease Control and Prevention found  perchlorate in all types of powdered infant formula, with higher  concentrations in milk-based formula. Similarly, a 2008 study on foods  produced in the lower Colorado River region reported perchlorate in milk  and various fruits and vegetables, including lettuce, but researchers  concluded that few individuals would be exposed to perchlorate levels  exceeding EPA’s reference dose. According to researchers we contacted,  only one study has attempted to quantify the contribution of various  sources of perchlorate to the food supply. A 2006 study concluded that  Chilean fertilizer and man-made perchlorate are the main and comparable  contributors to the perchlorate found in the food supply, while naturally  occurring perchlorate is a lesser source. Finally, researchers we spoke  with said that more studies are needed to better understand the extent to  which perchlorate exists in the food supply.
section_title: While the Likely Sources of Some Perchlorate Detections Are Known, Sources of Others Can Be Difficult to Determine
paragraphs: According to the perchlorate researchers we spoke with, concentrations  of perchlorate at or above 100 parts per billion are generally the result of  activities involving man-made perchlorate, such as the use of perchlorate  in manufacturing or as a solid rocket propellant. Researchers we  contacted told us that perchlorate detected at levels above 100 parts per  billion is generally man-made and is limited to a specific area. Further,  EPA, DOD, California, and Massachusetts officials told us they have  generally been able to determine the likely sources of localized high  concentrations of perchlorate, such as those detected at certain Superfund  sites.
Concentrations of perchlorate below 100 parts per billion can result from  the use of man-made perchlorate, natural processes, or the use of fertilizer  containing naturally occurring perchlorate. Researchers we spoke with  said that naturally occurring perchlorate formed atmospherically is  typically found in water or soil at 1 part per billion or less, while  perchlorate found in water or soil due to Chilean fertilizer can vary in  concentration ranges but generally is not found at levels greater than 30  parts per billion. Levels of perchlorate below 100 parts per billion can also  be attributed to various activities, including localized uses, such as  fireworks and road flares, which release perchlorate that is typically  diluted over a short time period, researchers said.
The sources of concentrations of perchlorate below 100 parts per billion  found around the country are often difficult to determine when there are  no records of historic use or when there is more than one potential source.  According to researchers we spoke with, current technology can often  differentiate between man-made and naturally occurring perchlorate, but  it cannot yet differentiate among different sources of man-made  perchlorate. DOD has funded the development of this technology, which  identifies the isotopic signature or fingerprint of a perchlorate sample and  compares the signature with known sources of perchlorate. According to  researchers we contacted, because man-made perchlorate and naturally  occurring perchlorate have different isotopic signatures, researchers can  distinguish between them. However, the technology is not widely used to  identify sources of perchlorate because it is expensive, and there is no  EPA- or state-certified identification method available. Therefore, federal  and state officials told us that they rely mainly on historical records to  identify sources of perchlorate. For example, officials identify sites where  they believe perchlorate was used and gather site-specific documentation  to ascertain perchlorate sources.
In the case of CERCLA sites, EPA officials said that they do not focus on  identifying perchlorate sources. Rather, they attempt to identify the  potentially responsible party for responding to the contamination, such as  current or former owners and operators of a site. CERCLA explicitly  identifies four types of parties that can be held responsible, including (1)  owners or operators of a site; (2) former owners or operators of the site at  the time hazardous substances were disposed of; (3) those who arranged  for disposal or treatment of hazardous substances (often called  generators); and (4) transporters of hazardous waste. According to EPA,  the agency identifies responsible parties by, among other actions,  reviewing documentation related to the site; conducting interviews with  government officials or other knowledgeable parties; performing historical  research on the site, such as searching for previous owners of the  property; sampling soil or groundwater at the site; and requesting  additional information from relevant parties.
section_title: DOD, NASA, and DOE Have Sampled for Perchlorate, Begun Cleanup Actions at Some Sites, and Taken Steps to Lessen Releases
paragraphs: DOD, NASA, and DOE have sampled for perchlorate at a number of their  facilities and have begun cleanup actions at some sites. According to DOD,  DOE, and NASA officials, by complying with current federal and state  waste disposal laws and regulations, they have lessened perchlorate  releases. Further, DOD and DOE have taken additional actions to lessen  perchlorate releases such as DOD’s development of perchlorate  substitutes.
subsections: section_title: DOD, NASA, and DOE Have Sampled for and, at Some Sites, Cleaned Up Perchlorate
paragraphs: DOD officials told us that the military services are to sample for  perchlorate at their installations wherever there is a release or suspected  release and follow the same CERCLA procedures as for other  contaminants. In general, to determine whether to sample for perchlorate  at an installation, DOD installations rely on historical records and  knowledge of perchlorate use, DOD officials said. According to our  analysis of DOD data from fiscal year 1997 through fiscal year 2009, DOD  sampled for perchlorate at 407 installations. Of the 361 installations that  reported not sampling, the primary reason cited for not sampling was that  there was no history, record, or indication of perchlorate use, according to  our analysis of DOD data. In addition, beginning in 2005, DOD began  requiring the military services to identify and evaluate the extent to which  the use of military munitions on operational ranges has resulted in the  potential for munitions constituents, including perchlorate, to migrate off- range and create unacceptable risk to human health and the  environment. In 2004, DOD collaborated with the state of California and  finalized a procedure for prioritizing perchlorate sampling at DOD  facilities in California, known as the California Prioritization Protocol.  Through this procedure, DOD and California screened 924 DOD sites  had the potential for perchlorate releases and concluded that the majo that  rity  of potential perchlorate releases associated with DOD sites had already  been identified through existing environmental programs and were being  addressed. Additionally, DOD and California officials agreed that, based  on the results of the prioritization, the current regulatory standards for  perchlorate, sampling results to date, as well as actions taken by DOD to  manage new releases and remediate known perchlorate releases, it  appears that DOD’s installations and formerly used defense sites are not  significantly impacting California public drinking water wells.
According to DOD’s current perchlorate policy, when detections in water  equal or exceed an identified threshold level—currently EPA’s health  advisory level of 15 parts per billion or a stricter state standard if identified  by DOD—DOD is to conduct further investigations to determine whether  additional action is warranted. Decisions as to whether to take further  action are generally made at the military service’s installation level.  According to Army, Air Force, and Navy officials, the actions taken at  installations may include conducting additional sampling, identifying the  contaminated media, characterizing the extent of contamination, and  adding perchlorate to the installation’s list of contaminants of concern.
Our analysis of data from DOD’s perchlorate database showed that  military service officials had decided to take action beyond initial  sampling at 48 of the 53 installations with perchlorate detections above 15  parts per billion. (See app. III.) Redstone Arsenal in Alabama and Edwards  Air Force Base in California illustrate some of the actions taken by the  Army and the Air Force beyond sampling to address perchlorate.
Redstone Arsenal. In 2000, the Army found perchlorate in groundwater  and soil at sites associated with rocket motor production. Between 2005  and 2009, the Army conducted an investigation of groundwater to  characterize the nature of the contamination and examined potential  treatment options, including ion exchange. According to DOD officials,  the Army has identified and planned a number of actions to remove  contaminated soils that serve as an on-going source of perchlorate to  groundwater. The Army is drafting a memorandum of understanding with  the city of Huntsville whereby the city will consult with the Army before  approving any well installation requests for areas with the potential for  perchlorate contamination. However, according to EPA officials, because  DOD has not signed an interagency agreement for Redstone, EPA has no  legal mechanism to ensure that the Army formally coordinates with  adjacent government entities to limit exposure to off-site wells that may be  contaminated. Finally, according to DOD officials, the Army is in the  process of obtaining regulatory approval from EPA for further site  investigation on some perchlorate contaminated areas, which could  determine the need for and feasibility of remedial action.
Edwards Air Force Base. In 1997 and 1998, the Air Force found  perchlorate in groundwater at two locations associated with solid rocket  propellant testing, including the North Base and the Air Force Research  Laboratory. The Air Force attributes contamination at North Base to past  NASA Jet Propulsion Laboratory activities at the site. However, as site  owner, the Air Force has taken responsibility for responding to the  release. According to Air Force officials, at North Base, the groundwater  plume has stayed on the base and has not contaminated drinking water  supplies. In 2003, the Air Force began operating an ion exchange system to  treat perchlorate in groundwater. By 2009, the Air Force had reduced the  level detected from 30,700 to 3,700 parts per billion. The Air Force also  removed 50 pounds of perchlorate from the soil and reduced the level  detected from 110,000 to 300 parts per billion in 2007. At the Air Force  Research Laboratory sites, according to Air Force officials, the Air Force  found it impractical to take remedial action because the perchlorate- contaminated groundwater was trapped in bedrock from 20 to over 200  feet below the earth’s surface and would be extremely costly to remove.  Furthermore, according to Air Force officials, it would take over 1,000  years to remediate perchlorate at the sites. EPA officials we spoke with  agreed that no solution existed to clean up this perchlorate. According to  Air Force officials, EPA and state regulators have agreed with the Air  Force’s decision not to clean up the sites. In addition, to treat perchlorate  in soil, the Air Force has removed 10 cubic yards of contaminated soil and  rock at one research laboratory site and has contracted for the removal of  an additional 40 cubic yards of contaminated soil.
EPA and state regulatory officials told us that the actions DOD takes to  respond to perchlorate contamination vary, depending on the military  service, installation, and personnel involved. For example, EPA officials  told us that staff at Edwards Air Force Base proactively took steps to  address perchlorate contamination at the base. According to Air Force  officials, personnel at Edwards began investigating perchlorate  occurrence in 1997. At the time, DOD had no perchlorate policy. In  addition, according to EPA officials, DOD had not approved funding to  treat perchlorate at Edwards, so personnel at Edwards convinced DOD to  fund research on perchlorate treatment technologies at Edwards that were  eventually used to remediate perchlorate at the base. In contrast,  according to a New Mexico state official, for several years, the Air Force  had not taken steps to remediate perchlorate at Kirtland Air Force Base  despite requirements to do so under state law implementing RCRA.  According to DOD officials, there is disagreement over whether further  actions at Kirtland should be conducted under CERCLA pursuant to  DOD’s perchlorate policy or under the state’s RCRA authority. According  to state and DOD officials, the Air Force submitted a site investigation  work plan in 2010 to address perchlorate releases, and Air Force officials  told us that they have begun investigating the site.
In addition to sampling for and, in some cases, cleaning up perchlorate,  DOD has provided funding for research and development of perchlorate  treatment technologies. This work, among other things, is funded mainly  through two programs—the Strategic Environmental Research and  Development Program and the Environmental Security Technology  Certification Program. From fiscal years 1998 through 2009, DOD spent  at least $84 million researching and developing perchlorate treatment  technologies, according to a DOD official. According to DOD, the  development and use of innovative environmental technologies support  the long-term sustainability of DOD’s training and testing ranges, as well as  significantly reduce current and future environmental liabilities. The  programs help DOD identify better ways to treat contaminants, including  perchlorate, a DOD official said. For example, several DOD installations  with perchlorate detections obtained funds for pilot treatment projects  from DOD and used the systems they developed to clean up perchlorate.
According to NASA officials, the agency has detected perchlorate at four  of the seven facilities where sampling occurred based on the historical use  of perchlorate. NASA has undertaken a major perchlorate cleanup effort at  one facility—the Jet Propulsion Laboratory in Pasadena, California, where  NASA detected a groundwater plume that had contaminated local drinking  water supplies. To respond to the release, NASA took several actions. To  clean up perchlorate in groundwater at the Jet Propulsion Laboratory,  NASA installed a biological fluidized bed reactor—a system that uses  bacteria to treat perchlorate. To clean up perchlorate in groundwater in  Altadena, California, a neighboring community, NASA installed an ion  exchange system, which began operating in 2004. In addition, NASA is  currently working with the city of Pasadena to construct a groundwater  treatment system. According to NASA officials, all the groundwater  treatment systems will need to operate for at least 18 years to clean up the  perchlorate plume and, as of 2009, the systems had been operational for 5  years. As of 2010, perchlorate groundwater detections are about 150 parts  per billion in the source area of contamination, compared with 13,300  parts per billion detected in 2002, according to NASA officials.
NASA is monitoring perchlorate at the other three facilities where it has  found perchlorate in groundwater—the Marshall Space Flight Center in  Alabama, the Stennis Space Center in Mississippi, and the White Sands  Test Facility in New Mexico. From 2003 to 2008, perchlorate detections at  Marshall ranged up to 4.4 parts per billion at the monitoring well with the  highest detections. NASA is determining what actions may be needed at  Stennis, where perchlorate detections ranged up to 40,700 parts per billion  at the monitoring well with the highest detections in 2005. According to  NASA officials, perchlorate contamination at Stennis is associated with  past DOD activities, such as munitions tests conducted more than 30 years  ago. Both NASA and DOD officials told us that they are currently  discussing the agency responsibilities for responding to perchlorate  releases. According to a NASA official, the agency is monitoring  perchlorate at White Sands as directed by the state of New Mexico and  generally detections fall below 1 part per billion. In addition to monitoring  at Marshall, Stennis, and White Sands, NASA officials said, for the past 25  years, the agency has conducted environmental monitoring after space  launches at the Kennedy Space Center in Florida, but it has detected no  perchlorate.
Finally, according to DOE officials, the agency has sampled and detected  perchlorate at all five facilities where there was a potential for  contamination based on the use of the chemical in high explosives  research, development, and testing. DOE has taken a variety of actions at  these five facilities.
At the Pantex Plant in Texas, in 1999, DOE detected perchlorate at 408  parts per billion in perched groundwater that sits above the regional  drinking water aquifer and, in 2007, after installing additional monitoring  wells, the agency detected perchlorate in the perched groundwater at  concentrations up to 1,070 parts per billion, DOE officials said. In June  2009, DOE detected perchlorate as high as 3,090 parts per billion in the  perched groundwater, DOE officials told us. With the approval of EPA  and the state of Texas, DOE is using bioremediation to clean up  perchlorate in the perched groundwater to 26 parts per billion and has put  restrictions in place to prevent the use of perched groundwater without  treatment.
At Lawrence Livermore National Laboratory Site 300 in California, DOE  first detected perchlorate in groundwater in 1998. The highest historical  detection was 92 parts per billion in 2008. DOE agreed with EPA and the  state of California in 2008 to clean up perchlorate to 6 parts per billion, the  state’s drinking water standard. DOE is treating perchlorate using ion  exchange and had reduced the highest level detected to 69 parts per billion  in 2009, according to agency officials. Further, DOE is planning to study  whether bioremediation can also be used to clean up the perchlorate- contaminated groundwater.
At Los Alamos National Laboratory in New Mexico, DOE detected  perchlorate in groundwater wells in the late 1990s. According to DOE  officials, in general, current perchlorate concentrations in groundwater  are less than 10 parts per billion, but detections range from 80 to 130 parts  per billion in a group of deep wells that monitor a perched groundwater  zone above the water supply aquifer. DOE is continuing to monitor the  levels of perchlorate in groundwater, according to agency officials.
At Sandia National Laboratories, also in New Mexico, between 2000 and  2009, DOE sampled for perchlorate in groundwater. Detections were at  levels less than 15 parts per billion except in one well, where the highest  detection in 2006 was 1,260 parts per billion. However, according to DOE  officials, the Air Force sampled the well recently and detected perchlorate  at only 2.7 parts per billion. In 2001, DOE detected perchlorate in soil  ranging from 16.7 to 1,040 parts per billion. According to DOE officials, the  state of New Mexico is currently requiring DOE to continue to monitor the  levels of perchlorate in groundwater at Sandia and evaluate the need for  further action.
At the Energy Technology Engineering Center at the Santa Susanna Field  Laboratory in California, in 2000, DOE detected perchlorate in  groundwater at 18 parts per billion, in soil at 3,600 parts per billion, and in  sediment at 6 parts per billion, DOE officials said. According to DOE  officials, the agency is planning additional sampling at new sites.
section_title: Improved Waste Disposal Practices and Research May Lessen Perchlorate Releases
paragraphs: DOD, DOE, and NASA officials we contacted agreed that perchlorate  contamination at their facilities was generally caused by waste disposal  practices that were commonly used before the enactment of key  environmental laws, such as RCRA. Historically, these practices included,  among others, disposing of perchlorate waste in open pits, open burning  and detonation of perchlorate, and using water to remove perchlorate  residue from rocket engines, which contributed to contamination in  groundwater. DOD, DOE, and NASA officials told us that their current  practices for perchlorate use and disposal follow current federal and state  environmental laws and regulations and, by doing so, lessen perchlorate  releases. For example, DOD officials told us that whereas historically  certain munitions were burned or detonated in open sites, they are now  handled in contained areas and burned on steel pads subject to  requirements for the management and disposal of the waste. Furthermore,  according to Air Force officials, perchlorate is now removed using a dry  process that seals the perchlorate before it is burned rather than a wet  process that allowed it to contact the ground and potentially contaminate  groundwater. In addition, at DOE’s Lawrence Livermore National Lab Site  300, to reduce the amount of contaminants in general, including  ammonium perchlorate, all but one of the outside firing tables—areas  outside the laboratory used to test high explosives—that could release  contaminants to the environment have been closed, according to DOE  officials. According to NASA officials, NASA believes that there is no  contamination caused by current perchlorate use during space shuttle  launches, because rapid combustion consumes virtually all of the  perchlorate during the first two minutes of flight and sampling around  rocket launch complexes, such as the Kennedy Space Flight Center, has  detected no perchlorate.
In addition to lessening perchlorate releases, from fiscal years 1999  through 2009, DOD spent at least $26 million developing perchlorate  substitutes, according to a DOD official. For example, in 1999, DOD’s  Army Research, Development and Engineering Command began  developing perchlorate substitutes for use in weapons simulators, flares,  and rockets, according to DOD officials. Regarding weapons simulators,  DOD researchers have developed perchlorate substitutes for training  simulator hand grenades and artillery shells for use on Army training  ranges, and DOD officials estimated that production of these simulators  will begin in early 2011. DOD officials estimated that the use of the new  weapons simulators should reduce potential perchlorate use on Army  training ranges by 35 to 70 percent. Additionally, DOD is conducting  research on ways to recycle perchlorate removed from discontinued  military munitions.
section_title: In the Absence of a Federal Standard, Some States Have Set Drinking Water Standards and Guidance Levels for Perchlorate
paragraphs: In the absence of a federal regulatory standard for perchlorate in drinking  water, California and Massachusetts have adopted their own standards. In  addition, at least 10 other states have established guidance levels for  perchlorate in various media.
subsections: section_title: California’s and Massachusetts’ Actions to Set Regulatory Standards for Perchlorate and Information on the Associated Benefits and Costs
paragraphs: California and Massachusetts have taken a variety of actions leading to  establishing state regulatory standards for perchlorate. California  promulgated its drinking water standard for perchlorate of 6 parts per  billion in 2007, and Massachusetts set a drinking water standard of 2 parts  per billion in 2006. Each state has also identified some of the benefits and  costs of setting these standards.
subsections: section_title: California’s Actions
paragraphs: California first identified perchlorate as an unregulated contaminant  requiring monitoring in January 1997 after the chemical was found in  drinking water wells near Aerojet, a rocket manufacturer in Sacramento  County that had used ammonium perchlorate as a solid rocket propellant.  Subsequent monitoring that year by the California Department of Public  Health found perchlorate in dozens of drinking water wells near Aerojet  and in southern California, principally in the counties of Los Angeles,  Riverside, and San Bernardino. State level testing also found perchlorate  in Colorado River water, an important source of drinking water and  agricultural irrigation water for southern California.
In 1997, in response to the detections of perchlorate in drinking water, the  California Department of Public Health set an action level of 18 parts per  billion based on the high end of EPA’s 1995 provisional reference dose  range, which had a drinking water equivalent of 4 to 18 parts per billion. In  1999, the department added perchlorate to the list of unregulated  contaminants that public water systems were required to monitor. In  January 2002, when EPA released a revised draft reference dose for  perchlorate that corresponded to 1 part per billion in drinking water, the  California Department of Public Health lowered its action level to 4 parts  per billion, the lower end of EPA’s 1995 provisional reference dose range  of values, and the lowest level that the analytical method in use at the time  could reliably measure. Also in 2002, California enacted a law requiring  the Office of Environmental Health Hazard Assessment (OEHHA) to  establish a public health goal and the Department of Public Health to  establish a state drinking water standard for perchlorate.
Under state law, before the Department of Public Health establishes a  standard, OEHHA must assess the contaminant’s risks to public health.  OEHHA’s risk assessment is required to contain “an estimate of the level  of the contaminant in drinking water that is not anticipated to cause or  contribute to adverse health effects, or that does not pose any significant  risk to health.” This level is called a public health goal. To calculate the  public health goal, OEHHA used data from the 2002 Greer study on the  effects of perchlorate on healthy adults, the same study used by the NRC  in its 2005 report, applied an uncertainty factor of 10 to protect pregnant  women and infants, and assumed that 60 percent of perchlorate exposure  comes from water to arrive at a proposed public health goal of 6 parts per  billion. According to OEHHA, the draft public health goal for perchlorate  was more extensively reviewed than any of the other public health goals  that OEHHA has developed. The draft technical support document for the  proposed public health goal was reviewed twice by University of  California scientists. EPA also peer reviewed the document. In addition,  OEHHA held two public comment periods and a public workshop on the  draft document. In March 2004, OEHHA established a public health goal  for perchlorate in drinking water of 6 parts per billion. In its technical  support document, OEHHA made a commitment to review the NRC report  assessing the potential adverse health effects of perchlorate upon its  completion and, if necessary, revise the public health goal. When NRC  released its report in January 2005, OEHHA reviewed the report and  determined that the findings were consistent with and supported the  approach that OEHHA used to develop its public health goal.
By law, the California Department of Public Health is required to set a  drinking water standard as close to the public health goal as is  economically and technologically feasible. To determine whether the  standard for perchlorate should be proposed at the public health goal level  of 6 parts per billion, the Department of Public Health evaluated the  feasibility of standards at different levels in terms of available analytical  methods for detecting perchlorate, monitoring costs, available treatment  technologies for removal to the proposed maximum contaminant level,  and the estimated fiscal impact on California drinking water utilities to  comply with the proposed standard. The department estimated that the  total annual costs to public water systems of a drinking water standard at  6 parts per billion would be about $23.9 million a year and that the total  population avoiding exposure would be 518,600, whereas the total annual  cost at 10 parts per billion would be an estimated $8.7 million with about  188,360 people avoiding exposure. The department noted that while the  cost impacts of a standard above 10 parts per billion would be minimal,  very little public health benefit would be achieved. To further evaluate the  feasibility, the department estimated that the annual costs for larger  systems that exceeded the drinking water standard would be $18 per  customer, while annual costs for smaller systems would be $300 to $1,580  per customer. Because of this difference, the department proposed to  provide variances for smaller systems based on affordability criteria.  Based on that analysis, the department promulgated a regulatory drinking  water standard for perchlorate of 6 parts per billion, which became  effective in October 2007. Now that a standard has been established,  California public drinking water systems must monitor to ensure that the  drinking water they distribute complies with this standard. Should a  system exceed the standard, it must notify the Department of Public  Health and the public and take steps to immediately come back into  compliance. Systems in noncompliance may face fines or permit  suspension or revocation, among other possible enforcement measures.  California Department of Health officials told us that public water systems  that exceed the standard generally treat the contaminated water or turn  off the contaminated well.
In addition to setting a regulatory standard for drinking water, California  adopted best management practice regulations for handling materials,  products, and waste that contain perchlorate. For example, those who  manufacture, package, distribute, receive, or generate certain materials  containing perchlorate must ensure they are properly contained in water- resistant packaging and labeled, and nonhazardous perchlorate waste  must be disposed of in a hazardous waste landfill or a composite-lined  portion of a nonhazardous landfill. These regulations, which were  adopted in December 2005, and became effective in July 2006, apply to any  person or business that manages—such as by using, processing,  generating, transporting, storing, or disposing—perchlorate materials or  waste, with certain exceptions.
section_title: Massachusetts’ Actions
paragraphs: In 2001, perchlorate was detected in groundwater at the Massachusetts  Military Reservation at 600 parts per billion and, in 2002, in monitoring  wells upstream from drinking water wells in the adjacent town of Bourne  at concentrations less than 1 part per billion. The Bourne Water District  shut three municipal wells when perchlorate was detected at levels less  than 1 part per billion and, in March 2002 formally requested guidance  from the Massachusetts Department of Environmental Protection on the  health significance of perchlorate in drinking water. Based on a review of  available information on the toxicity of perchlorate, including EPA’s 2002  draft health assessment for perchlorate and draft reference dose with a  drinking water limit equivalent to 1 part per billion, the department  recommended that the water district notify sensitive subgroups, such as  pregnant women, should perchlorate concentrations exceed 1 part per  billion and advise them to avoid consuming the water.
In 2003, the Massachusetts Department of Environmental Protection  convened an external science advisory committee to evaluate the peer- reviewed studies on perchlorate. Given the limited number of such studies  on perchlorate and its effect on sensitive populations, in February 2004,  the department established a drinking water health advisory level for  perchlorate of 1 part per billion consistent with EPA’s January 2002 draft  perchlorate health assessment. According to state environmental officials,  Massachusetts adopted an advisory level at 1 part per billion to protect  sensitive populations, specifically, pregnant women and their fetuses,  infants, children up to 12 years of age, and people with thyroid conditions.  In March 2004, Massachusetts initiated the process for setting a drinking  water standard by issuing emergency regulations requiring most public  water supply systems to test for perchlorate. Perchlorate was found in 9 of  600 systems tested, with perchlorate detections ranging from just below 1  part per billion to 1,300 parts per billion. Next, to assess the health risks  of perchlorate exposure, department toxicologists and an external science  advisory committee reviewed scientific studies, including the 2005 NRC  perchlorate study, as well as other information that had recently become  available, such as a 2005 study on perchlorate in breast milk and data  made available by FDA on perchlorate in food. To calculate a reference  dose for perchlorate, Massachusetts used the lowest-observed-adverse- effect level from the Greer study as the point of departure. Given the  limited sample size of the study (i.e., 37 subjects), Massachusetts used a  larger uncertainty factor (100) than applied by the NRC (10) to be more  protective of infants and pregnant women and their fetuses, and to allow  for data gaps. The department also assumed a 20 percent exposure from  drinking water to take into account the various other potential sources  and exposure pathways of perchlorate (i.e., food), especially for infants  and pregnant women, which resulted in a reference dose for perchlorate  with a drinking water equivalent level less than 1 part per billion.
To arrive at a drinking water standard, the department considered  information on the availability and feasibility of testing and treatment  technologies, as well as data that demonstrated that perchlorate can enter  drinking water as a by-product of hypochlorite (e.g., bleach) solutions  used as disinfectants in water treatment plants. The department chose to  set the standard at a level that does not create any disincentive for public  water systems to disinfect their water supplies. The department  determined that a maximum contaminant level of 2 parts per billion would  provide the best overall protection of public health, considering the  benefits of disinfection, while retaining a margin of safety to account for  uncertainties in the available data. In July 2006, Massachusetts became the  first state to set a drinking water standard for perchlorate. At the same  time, Massachusetts set cleanup standards for perchlorate, including a 2  parts per billion cleanup standard for groundwater that could be classified  for drinking water.
In addition to setting a regulatory standard for perchlorate, Massachusetts  has also taken action to minimize potential problems associated with  perchlorate by issuing best management practices guidance for blasting  operations and for fireworks displays. Also, Massachusetts officials  reported that they are working with EPA to develop guidance for the use  of hypochlorite solutions in water treatment plants.
section_title: Information on the Benefits and Costs of Setting a Regulatory Standard for Perchlorate in California and Massachusetts
paragraphs: While California and Massachusetts estimated the costs and benefits of  setting standards for perchlorate as part of their regulatory processes,  neither state has conducted a comprehensive analysis of the actual costs  and benefits of their perchlorate regulations. However, according to  California officials, setting a regulatory standard for perchlorate has  benefited public health. Massachusetts officials also cited protecting  public health, particularly children’s health, as a key benefit, and added  that cleaning up water supplies can also decrease the levels of perchlorate  in food. However, while both states estimated the benefits in terms of the  reduction in the number of people who would be exposed to perchlorate,  they did not attempt to quantify the dollar value of these benefits. In  addition, officials from both states told us that having a regulatory  standard allows the state and public water utilities to identify polluters  and hold them accountable for remediation. In particular, California  officials told us that adopting a perchlorate regulation ended DOD’s  reluctance to take action in response to perchlorate releases.  Massachusetts officials reported that adopting a standard provided the  impetus for the military to conduct perchlorate cleanup. Further,  Massachusetts officials said that having a standard provides a simple and  less costly means for determining whether remediation is necessary, as  well as when no further remedial response action is necessary.
Officials from both states said that their regulatory programs had costs to  the state. While California officials acknowledged that there were  administrative costs associated with developing its drinking water  standard, they did not have data on those costs. EPA regional officials also  cited the loss of water resources when contaminated wells were taken out  of service as a cost to the state and noted that additional costs may be  incurred to clean up the water should the state have to put some of these  wells back into service because of drought conditions. Massachusetts  reported that the process used to establish a drinking water standard cost  the state approximately $1.35 million, or the equivalent of about 9 staff  years. However, additional costs for monitoring and cleanup have been  minimal because the number of public water systems with perchlorate  detections above the level of concern has been small.
Officials from both states said that their perchlorate regulation also had  costs to public water systems, including initial and ongoing monitoring  costs, capital and construction costs to install treatment facilities, and  operations and maintenance costs.
Initial and ongoing monitoring costs. California state officials estimated  that to sample for perchlorate costs an average of $88 per sample, while  Massachusetts state officials estimated an average of $125 per sample. The  number of samples taken will vary by public water system and whether  sampling shows that the system is out of compliance with the state’s  drinking water standard. While each state estimated that monitoring costs  would be higher initially because all public systems would be required to  sample for perchlorate, officials from each state reported that most public  water systems are compliant and now only need to conduct annual  monitoring.
Capital and construction costs to install treatment facilities. In general,  determining the capital cost of a treatment facility, such as a blending  station, an ion exchange facility, or a biological fluidized bed reactor, will  depend on the individual site, according to California officials. Some of the  factors that can play a role in the cost include the concentration of  perchlorate, evidence of other contaminants, the need to purchase  additional land, and construction costs. According to officials from each  state, ion exchange is the technology generally used for treating  perchlorate in drinking water, although California has also identified  biological fluidized bed reactors as a cost-effective technology. Ion  exchange systems have relatively low capital costs and are simpler to  operate compared with biological fluidized bed reactors, which have  higher capital costs and take up more space, according to officials at  Aerojet.
Operations and maintenance costs. Operations and maintenance costs  will vary by type of treatment facility, water quality, and system flow rate.  California officials noted that an ion exchange system is more expensive  to operate than a fluidized bed reactor because of the cost of replacing the  resin to which perchlorate molecules adhere as water passes through the  system. When the resin becomes saturated with perchlorate, it must be  replaced and disposed of as waste. In comparison, a fluidized bed reactor  creates no waste disposal problem. Treatment costs for an ion exchange  system can run about $165 to $185 per acre foot of water, whereas  treatment costs for a fluidized bed reactor can run about $35 to $65 per  acre foot, according to officials at Aerojet. California officials told us that  the high operating costs of ion exchange can cause financial problems for  small water systems. For this reason, California allows a water system  serving less than 10,000 persons to apply to the department for a variance  from the perchlorate drinking water standard if water system officials can  demonstrate that the estimated annualized cost per household for  treatment to comply exceeds 1 percent of the median household income in  the community within which the customers served by the water system  reside.
section_title: Several States Have Issued Guidance Levels for Perchlorate
paragraphs: In addition to the regulatory standards set by California and  Massachusetts, at least 10 states have established for various purposes  guidance levels for perchlorate ranging from 1 part per billion to 18 parts  per billion for drinking water and from 1 part per billion to 72 parts per  billion for groundwater. Depending on the state, a particular level may  trigger public notice, serve as a screening tool for further action, or guide  cleanup action, among other things.
Table 1 provides a listing of state guidance levels for perchlorate in  drinking water.
Table 2 provides a listing of state guidance levels for perchlorate in  groundwater.
In addition, two states—Illinois and Wisconsin—have proposed regulatory  standards for perchlorate in groundwater. Finally, New Jersey proposed a  drinking water standard of 5 parts per billion in 2009, but the state’s newly  appointed Commissioner of the Department of Environmental Protection  decided in March 2010 to delay adopting a standard until EPA made its  regulatory determination, and New Jersey’s proposed rule has lapsed.
section_title: Agency Comments and Our Evaluation
paragraphs: We provided a draft copy of this report to DOD, DOE, EPA, and NASA for  review and comment. We received a written response from the Assistant  Deputy Under Secretary of Defense (Installations and Environment). DOD  believes that the report omitted a number of important facts and  conclusions, including the major conclusions of the California  Prioritization Protocol, the sources of perchlorate in Massachusetts, the  amount of perchlorate imported primarily for fireworks compared with  the amount of perchlorate used by DOD, information on the health risks of  perchlorate, and the conclusions of the EPA Office of Inspector General’s  report regarding perchlorate health risks. We do not agree. We believe the  report contains the most important facts relevant to our objectives.  Nonetheless, in response to DOD’s comments, we did modify the report to  provide some additional details on the results of the California  Prioritization Protocol. However, we made no changes regarding the  sources of perchlorate contamination in Massachusetts because this  information was already included in our description of Massachusetts’  actions to regulate perchlorate. We did not include information on the  amount of perchlorate imported into the United States, the health risks of  perchlorate, and the conclusions of the EPA Office of Inspector General’s  report, because these issues were beyond the scope of our report. For  example, we were asked to report on what is known about the likely  sources of perchlorate in the nation’s water and food supply, not on the  amount of perchlorate used for different purposes. Although an  organization may use a significant amount of perchlorate for a specific  purpose, the quantity used is not necessarily indicative of the amount of  perchlorate released into the environment. Similarly, we were not asked to  assess the public health risks of perchlorate exposure, so we did not  address it in this report. Moreover, the scientific community is still  debating health risk and, as we mentioned in the report, EPA has not yet  made a final decision whether to set a regulatory standard for perchlorate  in drinking water. DOD also provided technical comments, which we  incorporated into the report as appropriate. DOD’s comments and our  detailed responses are presented in appendix IV of this report.
DOE and EPA did not provide formal comments. However, they provided  technical comments by e-mail, which we incorporated as appropriate.  NASA had no comments on the report.
As agreed with your office, unless you publicly announce the contents of  this report earlier, we plan no further distribution until 30 days from the  report date. At that time, we will send copies of this report to the  appropriate congressional committees, Secretaries of Defense and Energy,  Administrators of the Environmental Protection Agency and National  Aeronautics and Space Administration, and other interested parties. In  addition, the report will be available at no charge on the GAO Web site at  http://www.gao.gov.
If you or your staff members have any questions about this report, please  contact me at (202) 512-3841 or stephensonj@gao.gov. Contact points for  our Offices of Congressional Relations and Public Affairs may be found on  the last page of this report. Key contributors to this report are listed in  appendix V.
section_title: Appendix I: Objectives, Scope, and Methodology
paragraphs: This report examines (1) what is known about the extent to which  perchlorate occurs in the nation’s water and food supply and its likely  sources; (2) what actions the Department of Defense (DOD), the National  Aeronautics and Space Administration (NASA), and the Department of  Energy (DOE) have taken to respond to or lessen perchlorate releases;  and (3) the actions states, such as California and Massachusetts, have  taken to regulate perchlorate.
To determine what is known about the extent to which perchlorate occurs  in the nation’s water and food supply and its likely sources, we took a  variety of actions.
To determine what is known about the extent of perchlorate occurrence in  the nation’s public drinking water systems, we obtained and analyzed  sampling data collected from 2001 through 2005 under EPA’s Unregulated  Contaminant Monitoring Rule 1. We assessed the procedure EPA used to  collect the data by reviewing the statistical design, sample selection, and  quality control methods used, and determined that the procedure was  sufficiently reliable for the purposes of this report.
To determine what is known about the extent of perchlorate occurrence in  water and other media at DOD, NASA, and DOE installations and facilities,  we obtained data on perchlorate occurrence at facilities owned or  managed by these agencies. Specifically, at DOD, we obtained and  analyzed data from their Perchlorate Survey Database for fiscal years 1997  through 2009. We assessed the reliability of the data for relevant variables  by electronically testing for obvious errors in accuracy and completeness.  We also reviewed information about the data and the systems that  produced them and interviewed officials knowledgeable about the data.  When we found inconsistencies in the data, we worked with the officials  responsible for the data to clarify these inconsistencies before conducting  our analyses. We determined that the data were sufficiently reliable for the  purposes of reporting on perchlorate sampling and detections at the  installations tracked by the database. We reviewed data provided by NASA  and DOE on perchlorate detections reported by their facilities. We also  interviewed officials from DOD, NASA, and DOE to determine that all data  were reported.
To determine what additional information existed on the extent of  perchlorate occurrence in water, we obtained data from EPA on  perchlorate occurrence at facilities on the National Priorities List—known  as Superfund sites. We also reviewed perchlorate occurrence data  provided by state environmental agencies in California, Massachusetts,  Arizona, and Texas.
To determine what is known about the extent of perchlorate occurrence in  the nation’s food supply, we performed a literature search to identify  research on perchlorate occurrence in food. We reviewed the results of  research conducted by the Food and Drug Administration (FDA), the U.S.  Department of Agriculture, the Centers for Disease Control and  Prevention, and academic researchers. We also interviewed officials from  FDA, the U.S. Department of Agriculture, and EPA, as well as researchers  at academic and private institutions, to identify what is known about the  extent of perchlorate in the food supply, the relative source contributions,  and any gaps in knowledge.
To determine what is known about the likely sources of perchlorate, we  reviewed research literature examining the different sources of man-made  perchlorate and its uses, as well as the conditions under which perchlorate  occurs naturally. We also interviewed EPA, U.S. Geological Survey, and  state officials; researchers from a consortium of public, private, and  academic entities developing an analytical method to determine the  sources of perchlorate; and other stakeholders to obtain information on  the history of perchlorate use, as well as developments in technology to  determine the sources of known perchlorate occurrences.
To determine the actions DOD, NASA, and DOE have taken to respond to  perchlorate releases, we reviewed and analyzed DOD data on perchlorate  occurrence from DOD’s Perchlorate Survey Database, DOD state  summaries, NASA and DOE perchlorate occurrence data, EPA data on  perchlorate occurrence at facilities on the National Priorities List, and  state regulatory agency reports. We also obtained and reviewed  documentation from federal and state agencies on the actions these three  agencies have taken to respond to perchlorate releases and the status of  these actions. We also interviewed agency officials and officials from state  and other federal agencies to obtain information and their views on (1) the  actions DOD, NASA, and DOE have taken to respond to perchlorate  releases; (2) the status of these actions; and (3) whether these actions  have lessened perchlorate releases. We visited the following DOD and  NASA facilities to discuss and observe their activities related to  perchlorate cleanup: Edwards Air Force Base (DOD), Redstone Army  Arsenal (DOD), the Jet Propulsion Laboratory (NASA), and the Marshall  Space Flight Center (NASA). We selected sites to visit that were identified  by EPA, DOD, and NASA officials as illustrative of their perchlorate  response actions. To determine the actions DOD, NASA, and DOE have  taken to lessen perchlorate releases, we reviewed documents from agency  officials and discussed current policies and practices they follow to lessen  perchlorate releases. We also visited Aerojet, a private facility that  manufactures and tests rocket engines for the space and defense  industries, to discuss and observe the operation of two types of  perchlorate treatment facilities that are also being used by federal  agencies.
To determine the actions California and Massachusetts have taken to  regulate perchlorate, we reviewed state documents, such as perchlorate  occurrence reports, risk assessments, and cost benefit analyses, and  interviewed state officials. To determine the actions of other states to  regulate perchlorate, we interviewed EPA regional officials and obtained  information from the Association of State Drinking Water Administrators  and identified states that have set advisory levels and cleanup goals for  perchlorate. We interviewed environmental and public health officials  from these states and obtained and reviewed documents related to  perchlorate guidance for drinking water and groundwater.
section_title: Appendix II: National Priorities List Sites Where Perchlorate Has Been Identified as a Contaminant of Concern
paragraphs: Appendix II: National Priorities List Sites  Where Perchlorate Has Been Identified as a  Contaminant of Concern  Redstone Arsenal (Army/NASA)
Phoenix Goodyear Airport Area, Unidynamics  Aerojet General Corp.
Edwards Air Force Base, Air Force Research Laboratory  Edwards Air Force Base, Jet Propulsion Laboratory   El Toro Marine Corps Air Station  Lawrence Livermore National Laboratory Site 300  Mather Air Force Base (former)
McClellan Air Force Base (former)
San Fernando Valley, Area 2-Glendale   San Gabriel Valley, Area 1-El Monte  San Gabriel Valley, Area 2-Baldwin Park  San Gabriel Valley, Area 4-Puente Valley  Sangamo Electric Dump/Crab Orchard National Wildlife Refuge  Fort Devens, South Post Impact Area  Naval Surface Warfare Center–Indian Head  Ordnance Products, Inc.
Lake City Army Ammunition Plant  Chemtronics (aka Amcel Propulsion Inc.)
Marine Corps Air Station Cherry Point  Marine Corps Base Camp Lejeune  Nebraska Ordnance Plant (former)
Radiation Technology, Inc.
Shieldalloy Corp.
Allegheny Ballistics Laboratory, Alliant Techsystems, Inc.
According to EPA, additional National Priorities List sites may have perchlorate at some level.  However, EPA does not currently have enough information to determine whether perchlorate is a  contaminant of concern at those sites.
section_title: Appendix III: Actions Taken by DOD at Installations with Perchlorate Detections above 15 Parts per Billion
subsections: section_title: Service
section_title: Appendix IV: Comments from the Department of Defense
paragraphs: The following are GAO’s comments on the Department of Defense’s letter  dated July 26, 2010, and provided by the Assistant Under Secretary of  Defense (Installations and Environment).
subsections: section_title: GAO Comments
paragraphs: 1.  We revised the text to provide some additional detail about the  California Prioritization Protocol. 2.  We disagree with DOD’s comment that, while the report mentions the  results of perchlorate sampling in Massachusetts, it fails to mention  that none of these detections were related to military sources and to  describe the perchlorate sources that were determined by the state.  This information appears on page 31 in the section of the report  describing Massachusetts’ actions to regulate perchlorate. 3.  Information on the amount of perchlorate imported primarily for  fireworks compared with the amount of perchlorate used by DOD is  beyond the scope of this report, which focuses on the extent and likely  sources of perchlorate occurrence, and federal agency actions to  respond to and lessen releases. Although an organization may use a  significant amount of perchlorate for a specific purpose, the quantity  used is not necessarily indicative of the amount of perchlorate  released into the environment. 4.  A discussion of the public health risks of perchlorate is beyond the  scope of this report. The scientific community is still debating health  risks associated with perchlorate. 5.  Appendix III describes the actions DOD has taken to respond to  perchlorate releases and notes when DOD’s assessment concluded  that no further action is required.  6.  We revised appendix III to note that DOD does not apply the 15 parts  per billion screening level to soil. 7.  A discussion of the public health risks of perchlorate is beyond the  scope of this report. 8.  This report draws no conclusions regarding the human health threat  that DOD releases of perchlorate currently pose to public drinking  water supplies because it is beyond the scope of our work.  9.  A discussion of DOD’s efforts to verify the conclusions from its  sampling program with state and federal regulators is beyond the  scope of our report. 10. A discussion of the public health risks of perchlorate is beyond the  scope of this report.  11. Because a discussion of the public health risks of perchlorate is  beyond the scope of this report, we did not evaluate or report on the  conclusions of the Inspector General’s report in this regard.  12. We disagree with DOD’s comment that our title is misleading. DOD is  only one of three federal agencies whose actions we describe in the  report and, therefore, we believe that the title is appropriate. 13. The report does not characterize the significance of detections. Rather,  we note the range of detections at DOD installations and the number  of installations with detections above 15 parts per billion—DOD’s  current threshold level for conducting further investigation when  perchlorate is detected in water to determine whether additional  action is warranted. 14. The report mentions that sodium hypochlorite solutions used as a  disinfectant in water and water treatment plants is a source of  perchlorate. See pages 2 and 32. 15. We revised the text to clarify the DOD sampling information presented  in the report, which includes the results of GAO’s analysis of data that  exists only in narrative format. 16. We revised the text to include the Army’s description of actions taken  at Redstone Arsenal. 17. We revised the text to clarify the Air Force’s position on the status of  actions being taken to respond to perchlorate at Kirtland Air Force  Base.  18. We revised appendix II to show that Mather and McClellan Air Force  Bases are closed. 19. We revised appendix III to attribute Camp Edwards/Massachusetts  Military Reservation to both the Air Force and the Army. 20. In appendix III, we revised the action column for McAlester  Ammunition Plant, China Lake Naval Air Weapons Station, El Centro  Naval Air Facility, NOLF San Nicolas Island, and NWS Seal Beach  Detachment Fallbrook to reflect the information provided by DOD.
section_title: Appendix V: GAO Contact and Staff Acknowledgments
paragraphs: John B. Stephenson, (202) 512-3841, or stephensonj@gao.gov.
subsections: section_title: Staff Acknowledgments
paragraphs: In addition to the individual named above, Stephen Secrist, Assistant  Director; Elizabeth Beardsley; Mark Braza; N’Kenge Gibson; Mitchell  Karpman; Susan Malone; Madhav Panwar; Jeremy Sebest; Ben Shouse;  Matthew Tabbert; and Kiki Theodoropoulos made key contributions to  this report.