[time-nuts] USGS Benchmark accuracy...?

[Michael Baker]

Hello, Timenutters--

There is a USGS survey benchmark on the side of the road
just a half-mile from my house.

Any guess as to how accurate these are?

I parked my pickup truck over the benchmark with the LH
box and antenna ( a 10 year-old Trimble surveyors antenna).
I only let LH run for an hour-- I am not sure how I could
leave a LH box out there for a long survey period without
running the risk of theft.  The survey marker is about 20 feet
off the side of the road in a grassy area and marked only by a
4-foot-tall plastic USGS geodetic pole next to the buried
concrete post.

The head of the marker post with the brass plate on the top
is flush with the surface, but covered with grass.  I had to
scratch around to find it.   There is also a second concrete post
in the ground about 30-40 feet away--  apparently you line up
the two concrete markers to give you a true cardinal direction.

Mike Baker
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