A fish consumption advisory impairs all of Indiana's Lake Michigan shoreline. The pollutants most frequently identified in Indiana waters include PCBs, bacteria, priority organic compounds, oxygen-depleting wastes, pesticides, and metals. The sources of these pollutants include combined sewer overflows, resource extraction, and land disposal.
Many sources are unknown.
High concentrations of PCBs and mercury were most common in sediment samples and in fish tissue samples. Ground Water Quality a A subset of Indiana's designated uses appear in this figure. The major sources of ground water contamination in Indiana are commercial fertilizer application, confined animal feeding operations, underground storage tanks, surface impoundments, landfills constructed prior to 1989, septic systems, shallow injection wells, industrial facilities, materials spills, and salt storage and road salting. Contaminants from these sources include nitrate, salts, pesticides, petroleum compounds, metals, radionuclides, and bacteria. Ground water protection programs are being implemented through the efforts of five state agencies.