This is job No. 1. It doesn’t matter how regular you are about maintenance if the person handling the tools doesn’t know what he’s doing. Says Caho: “You need someone who’s actually trained to do it.” From w.
[pdf] This regulation provides guidance for investigation, maintenance, and remediation drilling in and near embankment dams and levees and/or their earth and rock foundations. including investigation planning, site preparation, borehole advancement, subsurface testing, instrumentation installation, piezometer and well rehabilitation, grouting, and borehole completion.
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