**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** SUMMARY:IN NEBRASKA, THE EXCESSIVE USE OF SYNTHETIC FERTILIZERS IS CONTINUOUSLY LEADING TO HIGHER NITRATE LEVELS IN GROUNDWATER. MANY COMMUNITIES ARE CURRENTLY IMPACTED OR WILL LIKELY BE IMPACTED IN THE FUTURE. CURRENTLY, 117 OF THE NEARLY 550 GROUNDWATER-BASED COMMUNITY PUBLIC WATER SYSTEMS MUST PERFORM QUARTERLY SAMPLING DUE TO HIGHER NITRATE-N LEVELS. TEN WATER SYSTEMS CURRENTLY HAVE TREATMENT SYSTEMS IN PLACE. FOR EXAMPLE, IN HASTINGS, NEB., $46 MILLION WAS INVESTED IN AN AQUIFER STORAGE AND RESTORATION PROJECT TO MITIGATE DRINKING WATER NITRATE CONCERNS (DEPARTMENT OF ENVIRONMENTAL QUALITY, N.D.). IN THE BAZILE GROUNDWATER MANAGEMENT AREA (BGMA) THAT ENCOMPASSES TWENTY-ONE TOWNSHIPS OR 756 SQUARE MILES IN NORTHEAST NE, THE NITRATE CONCENTRATION IN DRINKING WATER WELLS HAS SHARPLY INCREASED RECENTLY, REQUIRING THE COMMUNITY PUBLIC WATER SYSTEM TO BUILD A REVERSE OSMOSIS PLANT TO TREAT FOR NITRATES. IF THIS TREND CONTINUES, MANY SMALL COMMUNITIES IN NE WILL NEED TO CONTINUE TO INSTALL COSTLY WATER TREATMENT FACILITIES TO MAINTAIN POTABLE DRINKING WATER. THIS SERIOUS PUBLIC HEALTH ISSUE IS NOT CONFINED TO NEBRASKA AS 37 STATES ARE ESTIMATED TO HAVE GROUNDWATER NITRATE CONCENTRATIONS GREATER THAN 5 MG/L, WITH MORE THAN 20% OF THE POPULATION IMPACTED IN 17 STATES (EPA, N.D.). CONSEQUENTLY, THERE IS AN URGENT AND CRITICAL NEED TO EVALUATE AND MOTIVATE IMPLEMENTATION OF BEST MANAGEMENT PRACTICES (BMPS) THAT CAN REDUCE NITROGEN LOSSES BELOW THE ROOT ZONE TO MAINTAIN ADEQUATE SUPPLIES OF SAFE DRINKING WATER.A FEW APPROACHES HAVE BEEN DEVELOPED TO IMPROVE NITROGEN MANAGEMENT AND NITROGEN USE EFFICIENCY AND REDUCE NITRATE LEACHING IN SEASON AND OFF SEASON. FOR EXAMPLE, DURING THE GROWING SEASON, COMPLEMENTARY USE OF MANURE AND COMMERCIAL FERTILIZERS HAVE BEEN RECOGNIZED TO REDUCE THE INPUT OF COMMERCIAL INORGANIC FERTILIZERS BUT STILL INCREASE CROP YIELD AND PROFITABILITY AND IMPROVE SOIL PROPERTIES WHILE DECREASING NITRATE LOADS TO GROUNDWATER. GROWING COVER CROPS DURING OFF-SEASON WINTER PERIOD PROVIDES ANOTHER OPPORTUNITY FOR REDUCING NITRATE LEACHING DURING WINTER AND SPRING SEASON. CARBON INJECTION BELOW-GROUND IS A NEW APPROACH FOR INTERCEPTING THE NITRATE BELOW THE CROP ROOTZONE. SO, AN INTEGRATED USE OF THESE IN-SEASON AND OFF-SEASON SEASON NUTRIENT MANAGEMENT PRACTICES CAN IMPROVE NITROGEN MANAGEMENT, CROP PRODUCTION AND FARM PROFITABILITY WHILE REDUCING NITRATE LOAD TO GROUNDWATER. SO, HERE WE PROPOSE RESEARCH DEMONSTRATION AND ADAPTATION OF COMPLEMENTARY USE OF COMMERCIAL INORGANIC FERTILIZERS AND MANURE, ALONG WITH CARBON INJECTION, AND COVER CROP TO REDUCE THE NITRATE LOAD TO GROUNDWATER.THE OVERALL GOAL OF THIS PROJECT IS TO IMPROVE PUBLIC KNOWLEDGE AND MOTIVATE ADOPTION OF RESEARCH-BASED INTEGRATED NUTRIENT MANAGEMENT PRACTICES THAT CAN PROTECT DRINKING GROUNDWATER QUALITY. AN ON-FARM RESEARCH DEMONSTRATION WILL BE USED TO DETERMINE THE IMPACT OF INTEGRATED IN-SEASON AND OFF-SEASON NUTRIENT MANAGEMENT PRACTICES. THE RESULTS OF THIS PROJECT WILL IMPROVE DRINKING GROUNDWATER QUALITY WHILE OPTIMIZING CROP YIELD AND PROFITS. TO ACCOMPLISH GOALS, WE PROPOSE THE FOLLOWING OBJECTIVES.RESEARCH OBJECTIVE 1: DEMONSTRATE IMPACTS ON CROP PRODUCTIVITY AND NITROGEN MANAGEMENT EFFICIENCY OF COMPLEMENTARY USE OF MANURE AND COMMERCIAL FERTILIZERS, CARBON SOIL AMENDMENTS, AND COVER CROPS. THIS WILL BE ACCOMPLISHED VIA AN ON-FARM TRIAL OVER A THREE-YEAR PERIOD.RESEARCH OBJECTIVE 2: EVALUATE AND DEMONSTRATE THE RETURN ON INVESTMENT AND SHORT-TERM ENVIRONMENTAL IMPACTS OF COMPLEMENTARY USE OF MANURE AND COMMERCIAL FERTILIZER, CARBON SOIL AMENDMENTS, AND COVER CROPS. CROP YIELD, BIOMASS, N UPTAKE, SOIL PROPERTIES, AND NITRATE LEACHING DATA WILL BE UTILIZED TO QUANTIFY NITROGEN USE EFFICIENCY, PERFORM A PARTIAL BUDGET ANALYSIS, AND ASSESS ENVIRONMENTAL IMPACT.EXTENSION OBJECTIVE 1: MOTIVATE ADOPTION AMONG FARMERS AND STAKEHOLDERS WITHIN THE STUDY AREA OF BMPS DEMONSTRATION TO IMPROVE NITROGEN MANAGEMENT EFFICIENCY AND MITIGATE NITRATE LEACHING TO GROUNDWATER WHILE MAINTAINING OR IMPROVING RETURN ON INVESTMENT. ESTABLISHED, SUCCESSFUL WORKING RELATIONSHIPS AMONG THE RESEARCH TEAM, NEBRASKA NATURAL RESOURCE DISTRICTS (NRDS), THE NATURAL RESOURCES CONSERVATION SERVICE (NRCS), AND COOPERATING FARMERS WILL SUPPORT ENGAGEMENT OF FARMERS AND THEIR ADVISORS IN PEER-TO-PEER EXCHANGE OF KNOWLEDGE, PERCEPTIONS, AND PRACTICES TO IMPROVE NITROGEN MANAGEMENT EFFICIENCY.EXTENSION OBJECTIVE 2: QUANTIFY THE IMPACTS OF INTEGRATED RESEARCH, DEMONSTRATION AND ENGAGEMENT EFFORTS ON CHANGES IN KNOWLEDGE, PERCEPTIONS, AND BEHAVIORS AMONG PARTICIPATING CROP FARMERS AND THEIR ADVISORS ON BMPS FOR IMPROVED NITROGEN MANAGEMENT EFFICIENCY.THE BROAD AND VARIED DISSEMINATION MECHANISMS CHOSEN WILL ENSURE THAT FARMERS, AGRONOMISTS, ACADEMICS, GOVERNMENT WORKERS, POLICY MAKERS, AND THE NRCS CAN BENEFIT FROM THE RESULTS OF THIS STUDY. THIS PROJECT IS SIGNIFICANT BECAUSE REDUCING GROUNDWATER NITRATE CONCENTRATIONS IS A CRITICAL CHALLENGE IN NEBRASKA THAT REQUIRES AGGRESSIVE ACTIONS AND NEW APPROACHES. DEMONSTRATING AND PROMOTING A HOLISTIC APPROACH TO CROP NUTRIENT MANAGEMENT THROUGH INTEGRATED, COMMUNITY-BASED PROGRAMMING IS EXPECTED TO IMPROVE FARMER RECOGNITION AND APPRECIATION FOR THE VALUE OF INTEGRATED NUTRIENT MANAGEMENT TO GROUNDWATER QUALITY, PRODUCER RETURN ON INVESTMENT, AND COMMUNITY HEALTH.