clemsnwill, did you look down in the stand pipe before you filled it with concrete to see if water was coming through the valve or flowing down the pipe through a rust hole? If you filled with concrete with water flowing, the current probably washed a small tunnel through while it cured. I have poured sawdust by the 50 gallon drum down around leaky valves before to stop small leaks. If you are still able to pour concrete down the stand pipe, you can by a pipe plug from aquacenter.com that has a rubber bladder that is expanded like a boat plug to stop the flow wile you fill the whole pipe with concrete.

-HH

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