Characterization of the State of In Situ Stress By Hydraulic Fracturing For a Nuclear Waste Repository In Basalt

Hydraulic fracturing tests designed to characterize the state of in situ stress were conducted in four deep boreholes. These tests are part of a site investigation program to assess the feasibility of constructing a nuclear waste repository in a basalt formation underneath the Hanford Site in southeastern Washington State. The results of these tests are examined in light of stress indicator data, which include core disking, borehole wall spalling, and fault plane solution data obtained at the site.