An active mine site is where geologic materials are currently being extracted from the earth. An inactive or abandoned mine site is not currently in operation and may not have an identifiable owner or operator. A phosphate mine is a site where phosphate ore is extracted from the earth. Active, inactive, and abandoned mines can contribute to ground water and surface water contamination. Precipitation can leach soluble minerals from the mine wastes into ground water or cause contaminated runoff into surface water. These wastes often contain metals, acid, and minerals. On-site storage of fuels or lubricants may also pose a risk to ground water or surface water sources if proper handling and storage procedures are not followed.