**AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** PESTICIDES, INCLUDING HERBICIDES, INSECTICIDES, AND FUNGICIDES, ARE TOXIC CHEMICALS THAT ARE USED TO CONTROL PESTS DURING CROP PRODUCTION. ACCORDING TO THE UNITED STATES GEOLOGICAL SURVEY, A HALF MILLION TONS OF PESTICIDES HAVE BEEN APPLIED TO CROPS ANNUALLY IN THE UNITED STATES. RATHER THAN STAYING IN THE FIELDS, THE APPLIED PESTICIDES CAN BE WASHED INTOSURROUNDING WATER SYSTEMS VIA AGRICULTURAL RUNOFF FORMED BY RAIN, IRRIGATION, AND MELTING SNOW. PARTICULARLY, THE PESTICIDE LOADS IN AGRICULTURAL RUNOFF CAN INCREASE SUBSTANTIALLY DURING EXTREME RAINFALL EVENTS THAT ARE OCCURRING MORE AND MORE FREQUENTLY BECAUSE OF THE CHANGING CLIMATE. SUCH AGRICULTURAL RUNOFF FROM THE OVER 300-MILLION-ACRE AGRICULTURAL LAND IN THE UNITED STATES IS, ARGUABLY, THE BIGGEST NON-POINT POLLUTION SOURCE FOR LAKES, RIVERS, AND GROUNDWATER, WHICH THREATENS THE SAFETY OF AQUATIC ECOSYSTEMS AND HUMAN HEALTH, AND THE SUSTAINABILITY OF AGRICULTURAL PRODUCTION. UNFORTUNATELY, WE HAVE LITTLE KNOWLEDGE ABOUT THIS NON-POINT POLLUTION BECAUSE THE CURRENT METHODS FOR QUANTIFYING PESTICIDES IN AGRICULTURAL RUNOFF ARE VERY EXPENSIVE AND TIME-CONSUMING.IN THIS PROPOSED RESEARCH PROJECT, WE AIM TO DEVELOP AN INEXPENSIVE SENSING PLATFORM FOR REAL-TIME ANALYSIS OF PESTICIDES IN AGRICULTURAL RUNOFF. AS CONTAMINATED WATER FLOWS THROUGH THE SENSING CHAMBER, PESTICIDES IN WATER WILL BE CAPTURED BY THE GOLD NANOPARTICLES RESTRAINED IN A BACTERIAL CELLULOSE SCAFFOLD, WHICH GENERATES FINGERPRINTING RAMAN SPECTRA FOR PESTICIDE IDENTIFICATION AND QUANTIFICATION. TO FURTHER IMPROVE THE QUANTITATIVE PERFORMANCE OF THE SENSOR, WE WILL USE LIGHT AS AN INTERNAL STANDARD TO REDUCE THE VARIATION OF RAMAN INTENSITIES ACROSS THE SENSOR SURFACE AS A RESULT OF THE UNEVEN DISTRIBUTION OF GOLD NANOPARTICLES. THE PERFORMANCE OF THIS PROPOSED REAL-TIME SENSING PLATFORM WILL BE TESTED AND OPTIMIZED USING ARTIFICIAL AGRICULTURAL RUNOFF SPIKED WITH THE FIVE MOST USED PESTICIDES AND THEIR MAJOR METABOLITES, AND FINALLY VALIDATED USING REAL AGRICULTURAL RUNOFF COLLECTED FROM THE CENTRAL SANDS REGION IN WISCONSIN. ANALYSIS OF PESTICIDES BY THEPROPOSED SENSING PLATFORM IS MUCH CHEAPER AND FASTER THAN THE CURRENT METHODS BASED ON SOLID-PHASE EXTRACTION AND LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY. THE PROPOSED TECHNOLOGY WILL ALLOW PEOPLE TO CAPTURE THE TEMPORAL AND SPATIAL VARIATION OF PESTICIDE LOADS IN AGRICULTURAL RUNOFF, WHICH ENABLES THE STAKEHOLDERS TO MAKE DATA-DRIVEN ACTION PLANS FOR MINIMIZING THE ADVERSE IMPACTS OF PESTICIDES ON AGROECOSYSTEMS.