The name Bertha, after Seattle's first female mayor, , was chosen by a panel (that included the Governor and Transportation Secretary) from 150 submissions from kindergarten through 12th graders, who were asked to submit female names with Washington state heritage. The winning entry, which was submitted by two elementary schools in and , was selected in December 2012.
[pdf] Drill stems must be designed to transfer drilling torque for combined lengths that often exceed several miles down into the , and also must be able to resist pressure differentials between inside and outside (or vice versa), and have sufficient strength to suspend the total weight of deeper components. For deep wells this requires tempered steel tubes that are expensive, and owners spend considerable efforts to reuse them after finishing a well.
[pdf] A soil sample core drill rig is specialized for retrieving core samples, providing detailed information about soil composition and structure. Core sample drilling involves using equipment to extract cylindrical samples of soil or rock, which are crucial for studying subsurface conditions.
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