You ask some good questions. I don't think they have been operational for some years , but they keep it open doing the minimum activity (not producing cement, perhaps using the quarry) required to keep permits.
The furnace stack is very low and high levels of mercury have been found in the fish at and near the area. Most likely the toxins are drawn down by the cool water. I personally would not eat any fish from the river.
I believe what Titan plans to produce will be on a much larger scale: 3X what the old plant used to produce! My biggest worry is when they want to burn hazardous waste and then we will have a toxic coctail added to our air.
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