Since the advent of modern warfare, the presence of mines and minefields has hampered the freedom of movement of military forces. The origins of mine warfare may be traced back to crude explosive devices used during the Civil War. Since that time, the use of land mines has increased to a point where there are now over 750 types of land mines, ranging in sophistication from simple pressure-triggered explosives to more sophisticated devices that use advanced sensors. It is estimated that there are about 127 million land mines buried in 55 countries. Land mines are considered to be a valuable military asset since, by slowing, channeling, and possibly killing opponents, they multiply the combat impact of defending forces. Their attractiveness to smaller military and paramilitary organizations, such as those in the Third World, is further enhanced because they do not require complex logistics support and are readily available and inexpensive. Virtually every combatant can make effective mines, and they will continue to be a viable weapon for the future. U.S. forces must be prepared to operate in a mined environment across the spectrum of military operations, from peacetime activities to large-scale combat operations. Detection is a key component of countermine efforts. In combat operations, the countermine mission revolves around speed and mobility. Mines hinder maneuver commanders’ ability to accomplish their missions because unit commanders need to know where mines are located so they can avoid or neutralize them. In peacekeeping operations, mines are used against U.S. forces to slow or stop daily operations. This gives insurgents a way to control traffic flow of defense forces and affect the morale of both the military and civilian population. Since World War II, the U.S. military’s primary land mine detection tool has been the hand-held metal detector used in conjunction with a manual probe. This method is slow, labor intensive, and dangerous because the operator is in close proximity to the explosive. The Army has also recently acquired a small number of vehicle-based metal detectors from South Africa to be used in route clearing operations and to be issued to units, as needed, on a contingency basis. Metal detectors are also sensitive to trace metal elements and debris, which are found in most soils. This limitation leads to a high level of false alarms since operators often cannot distinguish between a metal fragment and a mine. False alarms translate into increased workload and time because each detection must be treated as if it were an explosive. The wide use of mines with little to no metal content also presents a significant problem for metal detectors. For example, according to DOD intelligence reports, about 75 percent of the land mines in Bosnia are low-metallic and some former Yugoslav mines containing no metal were known to have been manufactured. In fact, the Army has stated that the inability to effectively detect low metal and non-metallic mines remains a major operational deficiency for U.S. forces. Given the limitations of the metal detector, DOD has been conducting research and development since World War II to improve its land mine detection capability. For example, during the 1940s the United States began research to develop a detector capable of finding nonmetallic mines. Since then, DOD has embarked on a number of unsuccessful efforts to develop a nonmetallic detector and to field a vehicle-based land mine detector. DOD now has new programs to develop a vehicle-based detector and an improved hand-held detector. DOD expects to field these new systems, both with nonmetallic capability, within the next 3 years. Airborne detectors are also being developed by both the Army and the Marine Corps for reconnaissance missions to locate minefields. Countermine research and development, which includes land mine detection, is funded by a number of DOD organizations and coordinated through a newly established Unexploded Ordnance Center of Excellence. The Army is designated as the lead agency for DOD’s countermine research, with most of its detection research funding being managed by the Night Vision and Electronic Sensors Directorate (NVESD) and the Project Manager for Mines, Countermine and Demolitions. The Marine Corps and the Navy are also supporting a limited number of land mine detection research efforts. Additionally, the Defense Advanced Research Projects Agency (DARPA) has been involved with a number of land mine detection programs throughout the years. In fiscal years 1998 through 2000, DOD funded over $360 million in countermine-related research and development projects, of which approximately $160 million was aimed specifically toward land mine detection. DOD sponsored an additional $47 million in research during this period for unexploded ordnance detection (which includes land mines) in support of other DOD missions such as humanitarian demining and environmental cleanup. Because of the basic nature of detection, these other efforts indirectly supported the countermine mission. Overall, DOD funding levels for countermine research have been sporadic over the years. Major countermine research initiatives and fieldings of new detectors have coincided with U.S. military actions, such as the Korean War, the Vietnam War, Operation Desert Storm, and the recent peacekeeping operations in the Balkans. Following each influx of countermine research funding has been a corresponding lull in activity. A countermine program assessment conducted for the Army in 1993 concluded that whereas mine developments have benefited from the infusion of leap ahead technologies, countermine tools have been essentially product improved counterparts of World War II ideas. However, according to DOD, countermine development is a slow process because of the technological challenges inherent to land mine detection. Not only must a detector be able to find mines quickly and safely through large variety of soils and at varying depths in battlefield conditions with clutter and even countermeasures, but it must also be able to discriminate between mines (which vary considerably in size, shape, and component materials) and other buried objects. DOD’s ability to develop meaningful land mine detection solutions is limited by the absence of an effective strategy to guide its research and development program. DOD maintains frequent contact with the external research community to constantly learn about new detection approaches and technologies. However, it has not developed a comprehensive set of mission needs to guide its research programs and does not systematically evaluate the broad range of potential technologies that could address those mission needs. In addition, its resources for conducting critical basic research for addressing fundamental science-based questions are threatened. Lastly, because DOD’s testing plans do not require adequate testing of land mine detectors in development, the extent of performance limitations in the variety of operating conditions under which they are expected to be used will not be fully understood. DOD has not developed a comprehensive and specific set of mission-based criteria that reflect the needs of U.S. forces, upon which to base its investments in new technologies in land mine detection. Although DOD’s overall acquisition process sets out a needs-based framework to conduct research and development, DOD has not developed a complete statement of needs at the early stages of research when technologies are first investigated and selected. The process calls for an evolutionary definition of needs, meaning that statements of needs start in very general terms and become increasingly specific as programs mature. Early stages of research are generated from and guided by general statements of needs supplemented through collaboration between the combat users and the research communities. In the case of land mine detection, the Army stated a general need of having its forces be able to operate freely in a mined environment. This need has received a broad definition, as “capabilities for rapid, remote or standoff surveillance, reconnaissance, detection, and neutralization of mines.” Further specification of the need is left to representatives of the user community and researchers to determine. It is only with respect to specific systems at later stages of the acquisition cycle that more formalized and specific requirements were established to guide decisions about further funding. Although we found that a comprehesive set of specific measurable criteria representing mission needs had not been developed, we did find some specific criteria in use to guide research efforts, such as rates of advance and standoff distances. However, a number of these criteria were established by DOD to reflect incremental improvements over the current capabilities of technologies rather than to reflect the optimal needs of combat engineers. For example, the Army was using performance goals to guide its forward looking mine detection sensors program. The objective of this program was to investigate and develop mine detection technologies to increase standoff and speed for route clearance missions beyond current capabilities. Performance goals included developing a system with a standoff of greater than 20 meters with a rate of advance of 20 kilometers per hour. However, these goals were primarily driven by the capabilities and limitations of the systems being considered. According to an Army researcher, they were based on what existing technologies could achieve in a limited time period (3 years) and not on what the combat engineers would ultimately need. During our assessment of technologies, which is described in the next section of this report, we found that the standoff desired by combat engineers was almost 50 meters for route clearance missions with a rate of advance of 40 kilometers per hour. One barrier to DOD’s developing a comprehensive set of mission needs is large gaps in information about target signature characteristics and environmental conditions. For example, significant information gaps exist about the rate at which land mines leak explosive vapors and the environmental pathways that the vapors take once they are released. Also, knowledge gaps about soil characteristics in future battlefields limit DOD’s ability to fully specify mission needs and knowledgeably select among competing technologies. They also reduce the pace of technological innovation by hampering researchers from predicting how their devices will function. DOD is currently funding research to answer several important questions in these areas. But, as discussed below, continued DOD funding is threatened. Just as DOD has failed to adequately specify countermine mission needs for assessing promising technologies, we found that it had not systematically assessed the strengths and the limitations of underlying technologies to meet mission needs. DOD employs a number of mechanisms to obtain ideas for promising land mine detection solutions.