Here it is sitting idle, shortly after it has started the trenching process:
The PRB is constructed using a mixture of coarse sand and zero-valent iron pellets. Here the coarse sand is being dumped into the hopper of the mix truck. The truck then mixes the sand with the iron pellets that are in a separate hopper and the mixture is pumped into the bucket of the John Deere end loader at right:
The end loader has a full bucket and it backs away to take its load to the trenching machine. The crane is getting ready to hoist the large white bag of iron pellets, which are dumped into a separate hopper in the mix truck.
The one-pass trenching machine is shown here in full operation as it digs a 32 foot deep trench and fills it with the mixture of coarse sand and iron pellets. The soil from the trench is deposited near the machine's tracks and then is swept away by the bucket of the power shovel. The trencher moves slowly backwards while it digs the trench and is capable of making a 200 foot long trench in a single work day. Note how slowly the trencher is moving by using the top of the fence post as a stationary reference point against the crawler tracks in the background.
ORIGINAL POST:
The trenching machine that Dewind will use to create the Permeable Reactive Barrier (PRB) in one pass has arrived. It is so large that it had to be shipped by truck in multiple pieces and then re-assembled on-site.
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The re-assembly
process began early on the 14th when the cat tracks were placed on the
ground in their proper spacing (right side of above photo).
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Six hours later, much of the trenching machine had been re-assembled.
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