GROUNDWATER GEOCHEMICAL RESPONSE TO CHANGES IN MANAGEMENT PRACTICES AT EAST TENNESSEE AGRESEARCH AND EDUCATION CENTER-LITTLE RIVER UNIT

The UT Dairy facility at ETREC Little River Unit is revising its waste management system to improve the separation of solids and liquids that are recycled back as land application for growing crops onsite. To more effectively manage these waste streams, a proprietary polyacrylamide blend flocculant has been added prior to storage and land application. The initial phase of the study has focused on providing updated background geochemistry and hydrogeologic properties for ~10 wells (depending on water level) and evaluating how the updated data differs from historical data collected after the wells were installed ~10 years ago. For most of the parameters tested, the current management practices (no flocculant) have not had a negative impact on the groundwater quality, suggesting that the nutrients from land-applied waste are being stored within soils and/or have been taken up by crops. The recent expansion of the dairy, and subsequent increased volumes of waste, required a revision to the waste streams to improve liquid and solid separation, including flocculant addition when needed. The second part of this study describes initial monitoring for any changes in groundwater chemistry after the first application of flocculant-treated waste. This work will also provide a workflow to ensure the flocculant continues to be a safe treatment without other unintended environmental impacts. These results will be instrumental in identifying the best management practices, particularly in terms of land application of processed effluent before and after the revision to the facility's waste treatment protocols.