I dont see how they can fail you for overdilution. When I was in the Army most of the time I couldn't go and would have to drink lots of coffee and water. When I was finally able to go the sample would look nearly white. Do you think they'd call you for a retest or just assume you're guilty because the sample is diluted? Sounds like total BS. I think that the pee test is unconstitutional because we're basically told to hand over evidence that could incriminate us.