By Melanie Petrucci, Senior Community Reporter
Shrewsbury – Daniel Rowley, the town’s superintendent of water and sewer recently provided an update on recently installed equipment for a pilot program to assess the presence of hexavalent chromium (also known as Chromium-6) in the water supply.
Rowley was joined by Rich Fox and Steve Johnson who are on his team and are working closely with the pilot program at the water treatment plant located at 45 Main St.
The pilot program is being conducted by AdEdge Water Technologies, based in Georgia, that specializes in the removal of contaminants from water.
Fox shared that the purpose of the program is to remove hexavalent chromium completely from the water supply. The cost to administer the study is close to $250,000.
“They are doing a pilot study using our water and all their processes and their chemicals is going to run for 14 weeks,” he noted.
The pilot is using two processes to determine the best way to go – biological and ionic exchange.
The installation inside the treatment plant is a smaller version of what the town could build should the pilot be successful, and the Town deem necessary with the approval of Town Meeting. If so, another plant the size of the water treatment plant could be built.
When asked how much hexavalent chromium was in the water before the program began, Johnson said, “We were at 3.5 parts per billion.”
“We have traces of it in town, but we don’t want to have any,” Fox added. “This is going to tell us what we need to do for permanent removal.”
Even at that level, the town was nowhere near the Environmental Protective Agency’s guideline of 100 parts per billion for total chromium.
To illustrate perspective, the pilot’s equipment can process a half a gallon of water per minute while the plant itself pushes out 3,000 gallons of water per minute. Four million gallons of water is processed on a typical day. Therefore, another treatment facility would be needed.
There are only two of the town’s wells that are picking up Hex chrome – Home Farm 6-4 and Home Farm 6-3.
At only 3.5 parts per billion, would it be worth the cost to build another facility? Perhaps finding another well source, putting in another well and getting away from those that contain the contaminant would be more cost effective, mused Fox.
“On the heels of this piloting we are going to pilot for the removal of PFAS [Per-and polyfluoroalkyl substances,] …we continue to monitor that on a quarterly basis…” Rowley shared. The pilot will be a similar proactive approach to the hexavalent chromium pilot but will last for a longer duration.
Rowley also said that unidirectional flushing would resume in the fall and should conclude next spring.