August 23 to September 2, 2004
Blakely Bore Site

Due to the instability of the hillside at our south end terminal site on Blakely Island, we needed to "bore" through the hillside 140' to 160' feet deep. Two 10" steel ducts were installed using an air compressor to drive a steel bit followed by the pipes into the earth.

The 10' pipe sections were drilled in about 1 1/2', and then they would pause and blow the tailings out of the pipe and proceed to drill again. At the end of each 10' section they would weld on the next pipe and drill again until they arrived at the base of the hill at the shoreline, which they had calculated to a tee!

Armadillo Underground, Inc. of Salem, OR performed the work. One pipe will accommodate the new submarine cable that was installed in October and the other will be for a future installation.

Click on a photo to view a larger and more detailed version

Clockwise from left:
  1. A crane loads a piece of the steel pipe into the bore pit. In the background is the portable air compressor that drives the bore machine.
  2. OPALCO Project Manager Terry Turner and Armadillo Underground Inc. Crew Foreman Kurt Leonhardt go over specifications for the bore.
  3. A.U.I truck
  4. The Blakely Bore site from the hill above the submarine cable terminal
  5. The truckload of steel pipe for the ducts and fuel storage for the compressors

Below: Steel pipe section being drilled into the hillside

Below-Right: The tailings being blown out

Below-Left: Placing the next pipe in line

Below: Welding two pipe sections together

Clockwise from left:
  1. The unstable cliff at Blakely South
  2. Looking down the cliff from the Blakely South Submarine cable terminal (and bore) site to the beach
  3. Finished bore, right on target
  4. The completed duct mounted in the vault.
  5. (L-R) OPALCO Project Manager Terry Turner, General Manager Randy Cornelius and Manager of Engineering Mark Tilstra survey the bore site.