356-4 A Multi-Contaminant Assessment of Private Well Water Quality Along the Texas Gulf Coast

Abstract:

Approximately 15% of the U.S. population relies on groundwater as a source of drinking water; however, comprehensive assessments of both conventional and emerging contaminants in private wells remain limited. This study evaluates private well water quality across five counties along the Texas Gulf Coast spanning an urbanization gradient, from the highly urbanized Houston metropolitan area to less developed coastal regions of central Texas. The study also includes wells located near industrial facilities and Superfund sites. Preliminary results indicate that total coliform was the most frequently detected contaminant exceeding drinking water guidelines. Elevated aluminum concentrations were likely associated with local geological conditions, while exceedances of EPA secondary drinking water standards, particularly for total dissolved solids and sulfate, were more common in wells located near the coastline. Initial nano- and microplastics analyses detected PVC and PET, indicating the presence of microplastics in well water and suggesting that well plumbing materials may contribute to their occurrence. PCB and PAH concentrations were below applicable drinking water guidelines in all wells analyzed, while ongoing PFAS analyses will further evaluate the occurrence of emerging contaminants, particularly in wells near industrial and Superfund sites. This comprehensive assessment will improve understanding of groundwater quality across the Gulf Coast and provide information to support private well owners, local agencies, and groundwater management strategies.

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