** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** THE GOALOF THIS PROJECTIS TO STUDYHOW THE USE OF BIOSOLIDSMAY CONTRIBUTE TO THE DEGRADATION OFWATER QUALITY IN AGROECOSYSTEMS. BIOSOLIDS, DERIVED FROM THE SOLID ORGANIC WASTE REMOVED AT WATER TREATMENT PLANTS,ARE A VERY VALUABLE SOIL AMENDMENT, HOWEVER, THEY CAN BE CONTAMINATED WITHPFAS (PER- AND POLYFLUOROALKYL SUBSTANCES), A CLASS OF EMERGING CONTAMINANTS THAT CAN BE HARMFUL TO HUMANS AND THE ENVIRONMENT. THEREFORE, THEIR USE IN FARMSCAN RESULT IN THE CONTAMINATION OF SOILS,WATER AND FOOD. OVER THE NEXT THREE YEARS, WE WILL STUDY THE TRANSPORT AND TRANSFORMATION OF BIOSOLID-DERIVED PFAS IN SOILS AND RIVERS USINGACOMBINATION OF LABORATORY AND FIELD EXPERIMENTS. WE WILL ATTEMPT TO ANSWER THEFOLLOWING SPECIFIC QUESTIONS: Q1. WHAT ARE TEMPORAL DYNAMICS DRIVING CONCENTRATION AND FLUXES OF PFAS IN BIOSOLID-TREATED SOILS AND THE AGRO-FLUVIAL SYSTEMS DRAINING THEM?, Q2. HOW ARE PFAS DYNAMICS IN FLUVIAL SYSTEMS RELATED TO ORGANIC MATTER CONCENTRATION AND CHEMICAL CHARACTER?, AND Q3. HOW DO TEMPERATURE REGIMES AFFECT THE EXPORT OF PFAS FROM BIOSOLID-TREATED SOILS TO THE HYDROLOGIC NETWORK?OUR PROPOSED RESEARCH HAS BROAD RELEVANCE TO AGRICULTURAL PRODUCERS AND REGULATORS; OUTCOMES OF OUR WORK WILL INFORM BEST MANAGEMENT PRACTICE DEVELOPMENT TO MINIMIZE RISKS TO AGROECOSYSTEM HEALTH AND PRODUCTIVITY. EFFECTIVELY AND SAFELY MANAGING BIOSOLIDS AS A SOIL AMENDMENT IS VITAL TO ENSURING SUSTAINABLE AGRICULTURAL ECONOMIES.