June 8, 1998
Section of Tolt Pipeline tested
by Woodinville Weekly staff
No, they're not drilling for oil in Kingsgate. The drill rig off of 124th Avenue N.E. is actually part of a corrosion prevention test on the Tolt River Pipeline. Norton Corrosion of Woodinville is conducting cathodic testing on a 3,500-foot section of the pipeline for Seattle Public Utilities.
They're doing it by drilling up to 100 feet below the pipeline and then driving low voltage DC current into the soil, according to Randall Goodlund of Norton Corrosion. It's a high school physics experiment on a large scale. Anodes bond on the pipeline, a cathode, and in the process prevent corrosion.
"The idea is to stop corrosion on the pipeline to extend its lifetime," Goodlund said. If test results show the pipeline is protected, the rest may be similarly done. But results won't be known until this fall, he said. Tests on sections of the pipeline on both sides of 124th will continue through next week. A portion of pipeline trail has been closed until that time.