104B State Water Resources Research Institute Scope 4: Sediment fingerprinting and biogeochemical erosional model of the Otter Creek Basin, Fort Kox Army Post, Kentucky

Otter Creek, which runs south to north along the west side of the Fort Knox Army Post, drains military lands that are often exposed to catchment disturbance resulting from loss of vegetative cover and collapsed pore structure of the soil. The Post has been the primary location for recurring training maneuvers ranging from light dismounted infantry and mechanized forces to munitions detonation and heavy (tracked) and wheeled vehicle training. Consequently, infiltration has been reduced and runoff increased, leading to episodic erosional events, siltation of adjoining streams, and decrease in wildlife habitat. The objectives of this study are to (1) characterize the extent of erosion within the Otter Creek drainage area and spatially determine sources of sediment inputs to the creek, (2) assess the impact of subsequent restoration efforts from training areas using stable C and N isotopes and the C/N atomic ratio to investigate the spatial erosional processes within the sub-watershed of Otter Creek, and (3) utilize a multivariate unmixing model to identify the inherited geochemical composition of the sediment sources.