I just looked at my billing log and when I needed to find/develop the same information for a pond in Garfield County, CO, I spend over 500 hours on the pre-work prior to starting facility design. It is very complex and a huge amount of "engineering judgement" needs to go into hundreds of decisions.
The liners (yes you have to have two) must be selected for their specific performance in contact with the fluids you are evaporating, and the design of the leak-detection system between the liners is a week's work.
Design of inlet facilities is another couple of weeks.
Finally, you have to work out your strategy for mucking the solids from the pond (not a trivial task, do you shut down the facility while removing the accumulated solids, or do you build your pond with sections to allow it to stay in service while solids are removed and liners replaced?)
I'm working on permitting a pond in New Mexico, and the first step in the permitting process (the regs allow 60 days) is now in its 10th month.
Oh, by the way, if your "impoundment" has over a certain number of acre-ft of water and/or if your largest wall is over a certain height then the pond suddenly must be permitted both by the state and by the Corps of Engineers. Have you thought about how to keep migrating birds off the pond?
I have a rule of thumb for your--hire someone who know what they're doing before you get into deep trouble.
David Simpson, PE
MuleShoe Engineering
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.
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