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Thursday 5.14 we spent nearly the entire day at the plant. Dan was testing out his turbidity and data-logging equipment, John and Wil were trying out wooden covers to seal off ports in the canal that lead to the sed tanks, and Antonio took advantage of the day to clean the plant with the plant operators.
The The idea of sealing the square ports with wooden covers did not work well. Even with a gasket made from an old rolled-up inner tube, the wood covers did not seal well at all. The concrete sockets appear to be too rough and uneven to make a good seal. We weren't even able to accumulate 2 inches of water in the channel before water started quickly leaking through into the sed tank we were trying to seal off. Because we see very little possibility of the covers working, we are exploring other possibilities. We are thinking of returning to PVC pipe fittings. Rather than making the entire chimney from PVC pipe, we could just set a short PVC socket into the top of the chimney and seal off that socket with a short nipple of PVC pipe. We plant to attempt these changes during the dry season when the plant can be bypassed for a week or so. In the meantime, when the operators clean the sed tanks they will clean both at once.
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