The impact of geogenic organic compounds leached from low-rank coals in groundwater has gained little attention outside a small group of researchers. Low rank coals contain many organic compound classes that may be potentially toxic. Ground water percolating through low-rank coal beds or through aquifers that are in communication with lignite beds extract a wide range of organic compounds from these chemically active and immature coals. One example of a low rank coal bearing aquifer is Carrizo Wilcox aquifer that extends from south Texas to Arkansas and Louisiana, providing groundwater to sixty counties. Preliminary investigation on groundwater quality in coal bearing Carrizo-Wilcox aquifer in northwest Louisiana and east Texas showed the presence of organic compounds such as polycyclic aromatic hydrocarbons, aromatics, phenols, terpenoids, and aliphatic hydrocarbons. The objective of this study is to understand the impact of leaching of low rank coals on water quality of Carrizo-Wilcox aquifer in east Texas. The hypotheses to be tested are 1) Low-rank coal samples collected from active coal mines along the aquifer trend will exhibit structural characteristics and organic functionalities similar to organic compounds in groundwater samples from wells. 2) Domestic wells intersected by low rank coal will have greater number and higher concentration of organic compounds compared to wells that are not in communication with low rank coal. Results from this study will identify and quantify organic compounds in the Texas aquifer and determine if there is any similarity of these compounds to the organic compounds that can be leached from coals.