The dewatering system is such a significant element of the Union Station project that it seems to deserve more explanation. So, as promised, here is a little more thorough report on the new process.

As a reminder, ground water is being pumped from 10 wells that were dug several months ago around the perimeter of what has become the bus box hole. Here is an overview of the process.  (Refer to the photo below.)

  1. Water is pumped through the three, blue and white, cylindrical containers (in the foreground of the photo) where the iron is oxidized.
  2. The water is then pumped to the six, large, blue and yellow, box-car-like containers to the left.  The iron settles to the bottom.
  3. Next, the water goes through 32 bag filters (16 are visible on a wooden platform behind the three blue and white containers). The bags in these filters must be changed every three hours throughout the day and night.
  4. From the bag filters, water is then pumped to the original, four, round green filters that are next to the dirt pile.
  5. Finally, clean water to pumped to the South Platte River.

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Two more of the large, blue and yellow tanks arrived Thursday afternoon. Since they have not yet been integrated into the system, it appears that they are being held in reserve for additional capacity or to replace a failed unit.