These pictures were taken in the spring of 2007 in preparation for repairing the large tank. The plan was to bring the small tank online during the repair process. At the last moment we realized that we did not have a good plan for maintaining the required CT.

The small tank was drained, cleaned, and sanitized.

The small tank prior to draining:

The small tank was surprisingly clean. The water was clear with only a slight collection of dust on the surface. There is some sediment visible in the top left corner of the picture. Mark should be there Wednesday at 9 or 10 to finish draining it, then start cleaning. He wondered if it might have been partially refilled. We will know tomorrow for sure. I don't see how we could partially fill it without overflowing.


The big tank, looking down at a patch on patch on patch:
  (click on any image to super size it)
This shot was taken while standing on the lid, prior to lowering the level. The electrodes used to control the pumps are dangling on the wires. The hardware holding the breather pipe on the contact culvert is corroded, or has iron deposits.

     
Here are 3 or 4 different materials used in attempted patches. The wider area epoxy was probably the last attempt, but it does not appear to overlap the earlier one. The black rubbery stuff pulled off very easily exposing bare concrete. The epoxy pulled off in small pieces and felt soft, but seemed to be on top of slime, not concrete. The four pictures above are a crude panoramic. The one on the far right has a fine vertical crack that we should consider grinding out for an inch or so.


Iron deposits on ladder hardware.


Epoxy delaminating.



below the vertical crack in the panoramic shot. This is why we have rebar. This is harmless.




The valve pit with the 2" drain marked. The 6" drain may be controlled by one of the 3 buried valves just behind the photographer.

     
 
This shows the 2" drain hole in the distance, just below the lid, and the electrical conduit that floods the plant when the tank overflows. Sorry for the different perspectives.

Sandy