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Old July 13th 07, 07:22 PM posted to rec.radio.amateur.antenna
Jim Lux Jim Lux is offline
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First recorded activity by RadioBanter: Mar 2007
Posts: 801
Default But we're built on a ledge! (was "Question on grounding rods")

Rick (W-A-one-R-K-T) wrote:
OK, per the thread on "Question on grounding rods", I'm supposed to use
8-foot grounding rods rather than twice as many 4-foot rods. I can see
that.

But, we're built on a ledge, one big wide rock that stretches from the
seacoast to the Vermont state line (that's why they call New Hampshire the
"Granite State"). I can get three feet depth at best before running into
solid rock. An electrician friend of mine says I can drive the ground rod
in at a 45-degree angle, but that would still run an 8-foot ground rod to
a depth of more than 5.5 feet below the surface.

Can't be done.

So, what do I do next?

I assume you're subject to the National Electrical Code in some version
or another?

What do you do? You use a Concrete Encased Grounding Electrode

Dig trench, lay wire, fill with concrete, done.

(The NEC also allows you to dig trench, lay your 8 foot rod sideways in
the trench, and then backfill.. but the CEGE is a better ground)