76 © The Containment of Underground Nuclear Explosions Figure 4-12--Standby Milk Surveillance Network All major milksheds west of the Mississippi River are part of the standby milk surveillance network. Samples are collected and analyzed annually. SOURCE. Modified from Environmental Protection Agency. essentially no possibility that a significant release of radioactive material from an underground nuclear test could go undetected. Similarly, there is essentially no chance that radioactive material could reach a pathway to humans and not be discovered by the Environmental Protection Agency. Allegations that a release of radioactive material could escape from the test site undetected are based on partial studies that only looked at a small portion of the total monitoring system. '® Such criticisms are invalid when assessed in terms of the total monitoring system, The radiation monitoring system continues to improve as new measurement systems and techniques become available and as health risks from radiation become better understood. Assuming that the monitoring effort will continue to evolve, and that such issues as the migration of radioactve material in groundwater will continue to be aggressively addressed, there appear to be no valid cnncisms associated with the containment of underground nuclear explosions. This is not to say that future improvement will not be made as experience increases, but only that essentially all relevant suggestions made to date that increase the safety margin have been implemented. Public confidence in the monitoring system suffers from a general lack of confidence in the Department of Energy that emanates from the enivronmental problems at nuclear weapons production facilities and from the radiation hazards associated with past atmospheric tests. In the case of the '6See for example. *‘ A review of off-site environmental monitoring of the Nevada Test Site.’” Bernd Franke, Health Effects of Underground Nuclear Tests, Oversight Hearing before the Subcommittee on Energy and the Environment of the Committee on Interior and Insular Affairs, House of Representauves, Sept. 25, 1987. Serial No. 100-35, pp. 120-144.