June 2020:
Maintenance performed on Fall Brook AMD Treatment Projects

Hedin Environmental and Signor Brothers Contracting are cleaning the limestone beds associated with the Fall Brook AMD Treatment Systems. Water quality has been deteriorating and we had not seen much improvement in the water quality with standard “stirring and flushing” methods previously used. Neil Wolfe of Hedin Environmental is trying a new approach to the cleaning using bull dozers. The tumbling action of pushing the pollution-caked stone to the perimeter of the beds as it rolls through the water generates very clean stone that is then piled along the edges of the bed until all of the stone is cleaned. The dirty, polluted water remaining in the bed is then flushed out, into the flush pond. It is retained in the flush pond to allow the solids to settle to the bottom. The cleaned stone is then spread back into the bed.


The limestone bed after the dozer pushed the material to the perimeter. The tumbling action with the water remaining in the bed cleaned the stone. They are drawing on the water collected in this bed to flush the stone in the next bed.

Starting to prepare this bed for the dozer. You can see how corrupted the stone is prior to the tumbling action and flushing. They are taking the beds down as close to the base layer as possible without compromising the integrity of the lining.

Shows the discharge pipe and the polluted water entering the flush pond.