stake are often inscribed with data relevant to the point that the stake is marking. A stake that marks a
bench mark, for instance, is inscribed with the symbol that identifies the bench mark and the elevation.
A stake that marks a station on a traverse is inscribed with the symbol of the particular station, such as 2
+ 45.06. A grade stake is inscribed with the number of vertical feet of cut (material to be excavated) or
fill (material to be filled in) required to bring the elevation of the surface to the specified grade
elevation. Figure 5-24 shows typical dimensions for an average-sized hub and stake. These dimensions,
however, may be modified as situations arise, such as material limitations.
Figure 5-24. Hubs and stakes
(3) Permanent Markers. Permanent markers are used to mark points that are to be used for a
long period of time. All permanent markers should be referenced so that they can be replaced if
disturbed. Horizontal and vertical control stations are generally marked with permanent markers. These
markers could be in the following forms:
(a) Surveyors Tacks, Spikes, and Nails. They are often driven into growing trees,
bituminous, or other semisolid surfaces as permanent markers. A nail will be more conspicuous if it is
driven through a bottle cap, a washer, a plastic tape, or a "shiner." A shiner is a thin metal disk much like
the top or bottom of a frozen fruit-juice can.
(b) Spad. It is a nail equipped with a hook for suspending a plumb bob. It is driven into
an overhead surface, such as the top of a tunnel. The suspended plumb bob indicates the point on the
floor that is vertically below the spad.
5-21
EN0591
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