I have a place on Sandlin and have never had a concern over water quality. The plant pumps water in from Monticello and dumps the heated water back into Monticello. They will pump water out of Sandlin and into Monticello to keep the water lever up on Monticello.
Water is generally pretty clear unless there is a bad rain storm and the creeks that feed into Sandlin bring in dirty water.
Where on Sandlin are you looking? I would not want to be real close to the plant only because even when it is not running at full capacity, it's pretty noisy. It's also all lit up at night (all night).