Laboratory Rock Testing and Hydrologic Calculations to Support the Underground Technology Program

Abstract : This report presents the results of laboratory testing and analysis conducted to support the Defense Nuclear Agency Underground Technology Program (UTP). The primary emphasis is on the UTP test site in the Rodgers Hollow area at Fort Knox, Kentucky. An extensive series of laboratory tests was performed on carbonate rock specimens prepared from cores retrieved from two deep drilled holes at the Fort Knox test site, including density/porosity characterization, ultrasonic wavespeeds, unconfined and triaxial compression, hydrostatic compression, and uniaxial strain loading. The testing and data analysis will support definition of the mechanical properties of the rock as functions of porosity, as well as assignment of porosity values for the various in situ layers, from which the layer properties can be assigned. Laboratory tests were also performed on rock from two shallow core holes in the Ul6a tunnel at Nevada Test Site, the site of the Dipole Hale test. The objective of these tests was to evaluate the air content in this porous tuff, which was partially saturated with water. This was done using both undrained uniaxial strain tests and standard mass/volume determinations. This report also presents the results of a detailed hydrologic study of the moderate to high permeability aquifer in the Louisville formation at the Fort Knox test site. The study integrated all hydrologic data from the site and included both analytical and two-dimensional numerical simulations.