Interpretation of hydraulic tests conducted in the waste-handling shaft at the Waste Isolation Pilot Plant (WIPP) site

A series of sub-horizontal boreholes from 8- to 41-feet deep were drilled from four depth levels in the waste-handling shaft at the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico. The boreholes were drilled at the 782- and 805-foot depth levels in a mudstone and a claystone of the unnamed lower member of the upper Rustler Formation; at the 850-foot depth level in bedded halite in the upper Salado Formation; and at the 1350-foot depth level in halite, anhydrite, and polyhalite of the Salado Formation. Examination of the cores recovered from one borehole at each level indicated no direct evidence of construction-induced fracturing. Pulse-injection test were conducted in packer-isolated intervals in six of the boreholes to estimate the formations's hydraulic conductivity and apparent formation pressure, and to determine whether or not there was evidence of construction-enhanced permeability up to one shaft diameter from the shaft wall. 12 ref., 67 figs., 19 tabs.