Preparations have been underway at Community Park for the dredging of Grovers Mill Pond that is slated to begin in August.##M:[more]##
At the center of the park, a large area has been fenced off with a cyclone fence and barbed wire, which encompasses the area near the Trolley Line Trail and includes the macadam path. The fenced-in area will eventually contain the dredged material, heavy equipment, and work trailers, and the parking area, where stones have already been put down, said Pat Ward, the Community Development Coordinator. “All of the equipment will come from the parking lot into that area,” she said.
The $4.6 million project has been timed around a variety of environmental restrictions. From November 1 to April 1 was the turtle hibernation period, and from December 15 to May 15 was the bald eagle restriction period, and then from May 1 to July 31, there are restrictions for fish spawning. The only thing the contractor, Select Transportation Inc. of Ohio, could do after April 1 was begin to put up the fencing and preparation of the contained area.
On May 15 the contractor was scheduled to begin building the dredged material containment area, including building large berms toward the pond side. In the beginning of August, when the restrictions are lifted, the contractor will be putting the dredge boat into the pond.
There are two types of dredging — dry and wet. Dry dredging involves draining the pond. But it is the wet dredging that will take place at Grover’s Mill Pond, which leaves the water intact, Ward says. “There will be a pipe that basically is attached to the dredge, which will have a suction and cutter blade that will go along the bottom of the pond, like a vacuum, sucking all of the material,” she said. The material will float through a pipe to the containment area. “It shouldn’t be smelly or messy,” Ward says. “It’s all underwater.”
The dredging and water work is schedule to be completed at the end of October, when a demobilization effort will take place. By the end of November, trailers and all work equipment should be removed, and fencing will be moved to the other side of the macadam path so that it only encompasses the dredged materials in the containment area. The material dredged from the pond will remain there for a year, while being maintained and monitored, to dry out. “At the end of the year, we’re going to see if it can be combined with soil, and see if it can level out the area. That will be a year from November,” Ward said.
“We know that the pond has some arsenic levels because of the fertilizer and pesticides that farmers used that leeched into the pond,” she said.
That is not abnormal for bodies of water in the township, explained Mayor Shing-Fu Hsueh, who said the Millstone River and Big Bear Brook also have shown some levels of arsenic in the past. He said this is mostly due to the farming activities in the 1960s and 1970s.
State officials are already working to clean up a portion of the Millstone River near the Grovers Mill area in the township. According to the New Jersey Integrated Water Quality Monitoring and Assessment Report, which was released by the DEP in 2006, this area of the river has high levels of suspended solids, acidity, and phosphorous. “The DEP considers it to be an impaired water body, meaning that it doesn’t meet our standards,” said DEP spokeswoman Karen Hershey. But, “the Millstone River is not the only river in New Jersey that doesn’t meet our standards.”
She says that DEP officials are working to clean up the river, and one way of doing so, is by restricting the amount of discharge that could go into the water. “The department does have a program where entities are given permits to release effluents, and those effluent discharges are highly regulated. When we’ve seen impairments like what we’ve seen in the Millstone River, we take measures to reduce the effluent that goes into that water.”
In addition, she says, rivers like the Millstone will not meet the DEP’s standards because of other causes, like stormwater runoff. “Millstone had phosphorous in excess of our standards, which usually is an indicator of pollution from stormwater runoff,” which can come from things like fertilizer. The DEP is working on releasing an updated report this year, as it’s required to do so every two years by federal law, which will provide updates on the river, Hershey said.
