PBO Strainmeter Installation Update: A Whole New Frontier! (5)

Overview

November 16, 2004

Hurray - it’s done! Crews completed the drilling for the first of eight strainmeter boreholes in the PNW.

Yesterday, with the cementing finished, a 6-inch hammer bit was inserted into the casing to drill out the float shoe. Unfortunately, progress was slowed when crews noticed that the bit was not firing properly. After a thorough inspection, the drill rig operators found the problem: a broken piston inside the hammer bit. Although normally used to drill through softer materials, the drillers attached the tri-cone bit and were able to make it through another 20 feet, reaching a total depth of 575 feet.

As the crews mobilize to start the drilling of the second strainmeter borehole, the first was capped and awaits coring by DOSECC. Coring will tell the crews exactly what type of rock is at the bottom of the hole and the ideal target location for the strainmeter installation. Coring will begin at the end of November - keep tuned for updates!