Transport and Fate of Nutrients and Indicator Microorganisms at a Dairy Lagoon Water Application Site: AN ASSESSMENT OF NUTRIENT MANAGEMENT PLANS - EPA600-R10-116

Environmental Protection Agency, it has not been subjected to Agency review and therefore does not necessarily reflect the views of the Agency, and no official endorsement should be inferred. iii The U.S. Environmental Protection Agency (EPA) is charged by Congress with protecting the Nation's land, air, and water resources. Under a mandate of national environmental laws, the Agency strives to formulate and implement actions leading to a compatible balance between human activities and the ability of natural systems to support and nurture life. To meet this mandate, EPA's research program is providing data and technical support for solving environmental problems today and building a science knowledge base necessary to manage our ecological resources wisely, understand how pollutants affect our health, and prevent or reduce environmental risks in the future. The National Risk Management Research Laboratory (NRMRL) is the Agency's center for investigation of technological and management approaches for preventing and reducing risks from pollution that threatens human health and the environment. The focus of the Laboratory's research program is on methods and their cost-effectiveness for prevention and control of pollution to air, land, water, and subsurface resources; protection of water quality in public water systems; remediation of contaminated sites, sediments and ground water; prevention and control of indoor air pollution; and restoration of ecosystems. NRMRL collaborates with both public and private sector partners to foster technologies that reduce the cost of compliance and to anticipate emerging problems. NRMRL's research provides solutions to environmental problems by: developing and promoting technologies that protect and improve the environment; advancing scientific and engineering information to support regulatory and policy decisions; and providing the technical support and information transfer to ensure implementation of environmental regulations and strategies at the national, state, and community levels. EPA currently requires that application of concentrated animal feeding operation wastes to agricultural fields follows a Nutrient Management Plan (NMP). The tacit assumption is that a well-designed and executed NMP ensures that all lagoon water contaminants (nutrients and pathogens) are retained or taken up in the root zone so that ground water is inherently protected. This research was designed to test the assumption that appropriate NMPs are protective of ground water and to address potential weaknesses in the land-application design and operation processes. A well-designed and managed NMP was implemented on two 6-by-6-meter plots at a dairy farm in San Jacinto, California, for several years using different forage and application patterns. …