Complex sentence: Porter noted that the dam has generated hundreds of millions of dollars in profits for operators since it started in 1970, but the Seneca have not received any of that money, although they lost 10,000 acres from their reservation, nearly a third of their total property.
Split into simpler sentences: Porter noted that the dam has generated hundreds of millions of dollars in profits for operators since it started in 1970, but the Seneca have not received any of that money. The dam caused huge losses for the tribe, taking 10,000 acres of their reservation, nearly a third of their total property.