The Division of Materials and Waste Management (DMWM) Geologist Group provides support for geologic and ground water issues related to the permitting, ground water monitoring, and, as necessary, assessment and corrective measures for solid waste landfills and construction & demolition debris (C&DD) facilities. Ohio’s regulations governing solid waste and C&DD landfills are designed to protect ground water resources. Modern-day landfills must meet siting criteria that consider groundwater resources, drinking water wells, and other potential receptors. Landfills are also engineered with composite liner systems, leachate collection systems, and other controls that are protective of human health, safety, and the environment. Landfill operators are required to install a groundwater monitoring network designed to detect any early stage of groundwater impact caused by the landfill. The groundwater monitoring network is frequently sampled during the operating life of the landfill and during the post-closure care period. The DMWM Geologist Group reviews hydrogeologic investigation reports, groundwater monitoring data, and other information to determine facility compliance and provide recommendations that address groundwater impact through assessment monitoring and corrective measures.