** AWARDS ISSUED PRIOR TO JANUARY 20, 2025, WERE FUNDED UNDER PREVIOUS ADMINISTRATIONS AND MAY NOT REFLECT THE PRIORITIES AND POLICIES OF THE CURRENT ADMINISTRATION.** TREATED SEWAGE SLUDGE OR BIOSOLIDS ARE AN ABUNDANT BYPRODUCT OF MUNICIPAL WASTEWATER TREATMENT. AS THESE BIOSOLIDS ARE RICH IN NUTRIENTS AND ORGANIC CARBON THEY ARE COMMONLY LAND APPLIED AS INEXPENSIVE FERTILIZER IF THEY MEET REQUIREMENTS FOR PATHOGEN REDUCTION AND TOXIC METAL LIMITS. HOWEVER, MANY ORGANIC CONTAMINANTS OF CONCERN (COCS), INCLUDING VARIOUS BIOACCUMULATIVE, TOXIC, AND/OR PERSISTENT CHEMICALS SUCH AS PHARMACEUTICAL AND PERSONAL CARE PRODUCTS (PPCP), POLYFLUORINATED ALKYL SUBSTANCES (PFAS), BROMINATED FLAME RETARDANTS (BFR), AND ANTIMICROBIALS, AMONG OTHERS CAN CONCENTRATE ON BIOSOLIDS DURING THE WASTEWATER TREATMENT PROCESS. THE PRESENCE OF COCS IN BIOSOLIDS MAY ALTER, BOTH POSITIVELY AND NEGATIVELY, SOIL MICROBE CARBON AND NITROGEN CYCLING ACTIVITY AND SOIL RESPIRATION (I.E., RELEASE OR UPTAKE OF GREENHOUSE GASES), THUS AFFECTING SOIL HEALTH.TO UNDERSTAND BIOSOLID COCS EFFECT ON SOIL HEALTH, THE PROJECT WILL INCLUDE AGRICULTURAL FIELD STUDIES AND GREENHOUSE STUDIES. SPECIFICALLY, OVER THE THREE-YEAR PROJECT MULTIPLE AGRICULTURAL FIELDS WHERE BIOSOLIDS HAVE BEEN HISTORICALLY APPLIED AND FIELD WHERE BIOSOLIDS ARE NEWLY APPLIED WILL BE SAMPLED FOR COCS AND SOIL MICROBIAL HEALTH AND ACTIVITY PARAMETERS. THESE FIELD RESULTS WILL BE COMPARED TO CONTROL SITES, WHERE NO BIOSOLIDS ARE APPLIED. FURTHER, TO EVALUATE A GREATER RANGE OF COCS IN BIOSOLIDS AND THEIR EFFECT ON SOIL HEALTH, CONTROLLED GREENHOUSE STUDIES WILL BE CONDUCTED. IN BOTH THE FIELD SETTINGS AND IN THE GREENHOUSE STUDIES THE PROJECT WILL EVALUATE SPATIOTEMPORAL COC CONCENTRATIONS AND SOIL HEALTH PARAMETERS INCLUDING CARBON AND NITROGEN CYCLING, TOTAL BACTERIAL AND FUNGAL NUMBERS, GREENHOUSE GAS RELEASE AND SEQUESTRATION, AND PLANT ROOT ZONE INTERACTION WITH SOIL MICROBES.THE PROPOSED PROJECT WILL IMPROVE THE UNDERSTANDING OF SOIL MICROBIAL HEALTH AND THE RESILIENCE AND SUSTAINABILITY OF AGRICULTURAL PRODUCTION SYSTEMS BY ELUCIDATING SOIL CARBON AND NITROGEN CYCLING IMPACTED BY COCS IN LAND APPLIED BIOSOLIDS USED FOR FORAGE CROP PRODUCTION. THE WORK WILL HIGHLIGHT WHEN AND HOW BIOSOLIDS CONTAINING COCS COULD BE UTILIZED AS INEXPENSIVE FERTILIZER WITHOUT HARMING SOIL HEALTH.