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Supplies:

1) Rod SET - the instrument - Design includes, the SET, pins, an insert collar and carrying case.

2) Shallow SET platform - Custom built aluminum platform with 4 legs.

4) 3" Aluminum pipe - 4 pieces per platform, length will depend on the depth of installation. Usually 12-24".

5) Stainless Steel Self tapping screws - 3/4" hex head.

6) Marker Horizon - We use Feldspar or sand. Need a mask for feldspar!

7) ½" fiberglass or pvc pipe- for marking the boundaries of the feldspar plots.

8) Cordless drill and saw.

Installation:

The general procedure for installing Shallow benchmarks is the following:

A) Build a platform.
B) Install the 4 legs of the shallow benchmark.
C) Secure platform and attach the Collar (if necessary).
D) Take your baseline SET reading.
E) Lay out your Marker Horizons (optional).


A) Step 1 - Build the sampling platform:

Click here for a details on platform construction


B) Step 2 - Installing the Shallow benchmark:

1) Determine how deep the 4 legs need to go into the ground. We have typically installed them from 12-24".

2) Cut the 4 legs out of the 3" aluminum pipe. You will need excess length for installing the legs. For example, say you want the legs to go into the ground 35 cm. The Shallow SET platform needs to be off of the ground about 20-30 cm (We try to keep it above high water). You will also need some extra to grab onto while installing, so for this example, we would end up cutting the pipes about 90-100 cm in length (~3 feet).

In addition, we drill a 5/8"-3/4" hole in the top of each aluminum pipe. Into the hole we slide a 9/16" stainless steel rod (~18" long). This is used as a handle to drive and twist the pipe into the ground. It makes installation a lot easier than just grabbing the pipe. We will also sharpen the leading edge of the pipe with a file to ease installation.

3) Lay the Shallow Platform on the marsh surface. It will serve as a guide for properly placing the legs.

Shallow SET
Lay on marsh surface
Shallow SET Shallow SET

4) Install the 4 legs through the supports on the Shallow Platform. Push them into the ground the specified distance. Mark the aluminum pipe with a line to show how deep to install it.

5) Slide the platform up to a suitable height. Try to level the platform as much as possible. The SET will level so don't worry if you can't get shallow benchmark perfectly level.

Raise the platform and level
Slide up platform and try to level

C) Step 3 - Secure the platform

6) Secure the supports on the Shallow Platform to the 4 legs. We use a cordless drill and stainless steel self-tapping screws (hex head). Once the platform is secured in place, you can cut the excess pipe from the platform (this is optional).

Shallow Platform


Shallow benchmark ready to screw to legs Screwing in legs (hard to see!)
Shallow SET Shallow SET

7) You are finished.

D) Step 4 - Take your baseline SET reading.

Click here for details on how to take the first readings.


E) Step 5 - Lay out your Marker Horizon (optional)

Click here for instructions on how to establish the marker horizons.