UMTRA Project water sampling and analysis plan, Gunnison, Colorado. Revision 2

Surface remedial action at the Gunnison Uranium Mill Tailings Remedial Action Project site began in 1992; completion is expected in 1995. Ground water and surface water will be sampled semiannually at the Gunnison processing site (GUN-01) and disposal site (GUN-08). Results of previous water sampling at the Gunnison processing site indicate that ground water in the alluvium is contaminated by the former uranium processing activities. Background ground water conditions have been established in the uppermost aquifer (Tertiary gravels) at the Gunnison disposal site. Semiannual water sampling is scheduled for the spring and fall. Water quality sampling is conducted at the processing site (1) to ensure protection of human health and the environment, (2) for ground water compliance monitoring during remedial action construction, and (3) to define the extent of contamination. At the processing site, the frequency and duration of sampling will be dependent upon the nature and extent of residual contamination and the compliance strategy chosen. The monitor well locations provide a representative distribution of sampling points to characterize ground water quality and ground water flow conditions in the vicinity of the sites. The list of analytes has been modified with time to reflect constituents that are related to uranium processing activities and the parameters needed for geochemical evaluation