Chapman Creek, a tributary to the Mad River, passes within about 500 feet of a landfill near Tremont City, in Clark County, west-central Ohio. In autumn 2000, the ground-water/surface-water relation was investigated by use of piezometers, seepage meters, temperature monitors, and a gain-loss study. Four piezometers were installed in the streambed along about a 1-mile reach, inclusive of the landfill. Four seepage-meter tests were done at locations near two of the piezometers. Four temperature-monitoring stations were established along a reach of about 700 feet near the landfill. A fifth temperature station was located near a piezometer about 3,000 feet downstream from the landfill. A streamflow gain-loss study was done over a 3-mile reach that included the reaches studied with the other methods. The data from the piezometers, seepage meters, and temperature monitors indicated an apparent change from losing to gaining and back again several times over fairly short distances. The gain-loss data indicated that the creek was consistently a gaining stream over the 3-mile reach. Investigation of streambed conditions and local geology revealed that the streambed consists of sand and gravel overlying a finegrained till layer. The stream water readily moves in and out of the coarse streambed such that the piezometers, seepage meters, and temperature monitors measured the local flow in the streambed; therefore, these data did not reflect the true relation between the creek and ground water. On the other hand, the gain-loss study, less affected by the movement of water in the streambed, showed that Chapman Creek probably is a gaining stream throughout the 3-mile reach.
