I've not heard of a Pan-American Underwater Games. The traditional Pan-Am games is scheduled for Guadalajara Mexico in 2011 but that is the 28 official Olympic sports plus this time Rugby and Racquetball.

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An aquifer is a water bearing layer of rock or soil. Aquifers are separated by impermeable layers of rock or clay called an aquitard. Aquitard, however may sound a bit offensive to some, and therefore we will be changing the name to Aquachallenge.