As part of the offsite monitoring program, drinking water samples are collected for radiological analysis at Atomic City, Craters of the Moon, Howe, Idaho Falls, Mud Lake, Shoshone, Minidoka, and at the public rest stop on Highway 20/26.. The samples are analyzed for gross alpha and beta activities and for tritium.
Surface water is sampled at three springs located downgradient of the INL Site: Alpheus Springs near Twin Falls; Clear Springs near Buhl; and a trout farm near Hagerman. The samples are analyzed for gross alpha and beta activities and for tritium.
The ESER Program also collects surface water samples from the Big Lost River. The Big Lost River is an intermittent, ephemeral body of water that flows only during periods of high spring runoff and releases from the Mackay Dam, which impounds the river upstream of the INL Site. When sufficient water is flowing through the INL portion of the Big Lost River, samples are collected and analyzed for gross alpha and beta activities, and for tritium, and for specific gamma radionuclides. When samples are collected from the Big Lost River, Birch Creek is also sampled for comparison.
Geological Survey has monitored ground and surface water at the INL since 1949. The USGS also conducts
special studies of the groundwater of the Snake River Plain.
A summary of these studies is provided in the
Annual Site Environmental Report for the INL.