Hole History, Rotary Hole DC-7, Hanford, Washington

摘要

The purpose of hole DC-7 was to drill through the Umtanum basalt flow to provide a borehole for hydrological testing, seismic shear and pressure wave velocity studies, and geophysical-electrical logging measurements of the strata penetrated for the Basalt Waste Isolation Program. The drilling of hole DC-7 commenced October 19, 1977 and was completed December 2, 1977. The original target depth of 3,900 feet was exceeded by 199 feet to a total depth of 4,099 feet under the direction of Rockwell Hanford Operations. The open hole diameter is 8 exp 5 / sub 8 inches. The open hole interval is 1,319 feet and extends from the longstring casing depth of 2,780 feet to the total depth of 4,099 feet. Hole DC-7 was completed successfully and capped. Hydrological testing and various logging measurements will be performed at a later date. (ERA citation 04:012637)