The National Agricultural Pesticide Risk Analysis (NAPRA), is one of two official NRCS methods for evaluating the complex environmental risks of pesticide use. It was developed jointly by NRCS and the University of Massachusetts. NAPRA uses the USDA Agricultural Research Service's GLEAMS Model (Groundwater Loading Effect of Agricultural Management Systems). NAPRA is the second and third tier of NRCS's three tiered method for assessing water quality related pesticide risks. NRCS uses the Soil/Pesticide Interaction Screening Procedure (SPISP) as a first tier pesticide screening tool. We are currently developing a Windows(tm) version of SPISP (WIN-PST), which will be enhanced with climate, management and pesticide toxicity considerations, supported with NAPRA analysis of typical pesticide use scenarios.NAPRA evaluates the potential loss of pesticides to ground and surface waters by modeling pesticide movement, toxicity and crop management techniques under specific climatolgical and soil conditions. NAPRA implementation within states has been supported by EPA with money from Section 319 of the Clean Water Act. In Indiana, NAPRA is being used to implement their EPA mandated State Management Plan for pesticides. In Idaho and Texas, NAPRA it is being considered as a means to help farmers meet EPA's Total Maximum Daily Loads for pesticides. In New York, NAPRA is being implemented in several test counties to evaluate its use in IPM recommendations.
NRCS also uses SPISP and NAPRA technology at the national strategic planning level. "An Information Aid for Assessing Possible NRCS Involvement in the State Management Plan Process for Regulation of Pesticides," (http://www.nhq.nrcs.usda.gov/land/pubs/pestsmp.html) was developed to show where NRCS needs to be prepared to assist farmers and State water quality agencies in reducing the loss of pesticides from farm fields. The analysis was conducted by the Resource Assessment and Strategic Planning Division (RASP) and the National Water and Climate Center - National Agricultural Pesticide Risk Analysis (NAPRA) Team. Its principle purpose is to show which watersheds have the greatest potential for pesticide loss at concentrations exceeding drinking water standards, and where EPA mandated State Management Plans (SMP's) could have the greatest impact on NRCS activities. The document addresses pesticide risk for both groundwater and surface water, although SMP's currently apply only to groundwater. While the document was written to address proposed pesticide regulation, it applies equally well to: 1) priority area designation for voluntary programs and 2) targeting technical assistance to meet water quality goals for watershed protection. Although the document only addresses the five herbicides that require SMP's, we currently have data for 133 pesticides.
Once a watershed has been targeted for preventative actions, more detailed field level models such as NAPRA can be used to determine where the most critical areas are within the watershed, and what kinds of alternative management strategies would be required to meet water quality goals. The NAPRA process has been specifically designed to approximate environmental risks of alternative management strategies. NAPRA results estimate relative environmental risks with pesticide toxicity exceedence probabilities and loadings over many years of simulation. NAPRA includes the impacts of climate, water management, soil management, crop management, pesticide management and pesticide toxicity to non-target species. The limits of the evaluation are bottom of root zone and edge of field.
Water quality goals for a watershed will be determined by state and local governments. To achieve these water quality goals, the relatively simple field-by-field approach currently being implemented by NRCS must be expanded to assess the effects of alternative practices on a watershed basis. NAPRA can be used with the Natural Resources Inventory (NRI) or other land use and soils data to identify areas within a watershed that need special emphasis pest management planning. Field office staff in these areas can then consult with producers and crop consultants to ascertain existing practices, and to promulgate economically feasible alternatives. NAPRA can be used again to test the alternatives to determine if they are adequate to meet water quality goals for the watershed. Using NAPRA to target technical assistance to high risk areas within high risk watersheds, is the only practical way to substantially improve water quality with limited resources.
NAPRA implementation has two phases: 1) development of NAPRA Pesticide Loss Databases by national and state level specialists, and 2) NAPRA reports generated from these data that quantify the relative environmental risks associated with each conservation alternative. NAPRA implementation requires a team effort. NRCS seldom has all the expertise necessary to fully parameterize the model, so it is imperative to partner with other agencies, private industry, the agricultural community, and the environmental community.
The ultimate goal is to help farmers choose pesticide management alternatives that reduce hazardous pesticide losses in environmentally sensitive areas. Traditionally, agricultural producers have made pesticide management decisions based on efficacy and economics. It is now essential to factor environmental risk into the decision making process. Adoption of practices such as reductions in pesticide use, improved efficacy of pesticide applications through integrated pest management, matching pesticide and management practice selection to site conditions, and the use of pesticides that are less toxic to the environment will be necessary. Using models to estimate the environmental benefits of these practices can help agricultural producers make more informed decisions that help meet the environmental goals of natural resource conservation.
About the Author:
Mr. Joseph K. Bagdon
Address:
USDA - Natural Resources Conservation Service
National Water and Climate Center
451 West Street
Amherst, MA 01002Phone: (413) 253-4376
Fax: (413) 253-4374
E-Mail: jbagdon@ma.nrcs.usda.govMr. Bagdon is the National Pest Management Specialist and NAPRA Team Leader at the National Water and Climate Center - Water Science and Technology Team at the USDA-Natural Resource Conservation Service in Massachusetts. He received his BS in 1980 from the University of Massachusetts in Plant and Soil Sciences. He was a Vegetable, Tobacco and Dairy Farmer, a Soil Conservation Technician with the USDA Soil Conservation Service, a County Executive Director with USDA Agricultural Stabilization and Conservation Service, Soil Conservationist with USDA Soil Conservation Service, Founder and Project Leader for NAPRA: National Agricultural Pesticide Risk Analysis, Resource Conservationist - Natural Resources Conservation Service and Pest Management Specialist for the Natural Resources Conservation ServiceIn his current position, he is responsible for pest management related technology and technical policy within the agency. His main interest is pesticide environmental risk. He serves on several national interagency technical committees, including the FIFRA Exposure Modeling Work Group and USDA's 75% IPM by the Year 2000 Subcommittee. He recently represented USDA at the International Organization for Economic Cooperation and Development Workshop on Pesticide Risk Indicators, in Copenhagen, Denmark. His primary focus over the next several years will be to partner with the Conservation Technology Information Center, to nationally promote pest management as one of the "Core 4" practices that all farmers need to implement to help conserve our Nation's natural resources.