
01-15-2005, 10:46 AM
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Senior Club Cobra Member
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Join Date: Dec 2001
Location: Shasta Lake,
CA
Cobra Make, Engine:
Posts: 26,615
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Not Ranked
Mike,
It must be at least 4 feet down in the ground on all edges to prevent illegals from tunneling in. Then vibration survellance sensors planted ever 50 feet to detect any attempt at digging.
Ron 
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