Raised water table levels at a closed Rhinebeck landfill have town officials and the State Department of Environmental Conservation, concerned, but local disagreement on what to do has put projected solutions on hold.
The 8.5-acre landfill on Stone Church Road — in a a DEC wetland — was established in the 1950s and closed in 1997. Since then, two beavers have moved into the area and built dams. That appears to have caused a 2 or 3 foot rise in the water table.
And because fluctuating water levels can allow waste material to access the water supply, the DEC has mandated that the town address the problem.
The Rhinebeck town board approved the purchase of two Havahart animal traps at their Nov. 19 meeting, but ongoing board member disagreement has stalled any decision on how to proceed.
“The question is if the higher water table since the beavers built their dam is really doing anything,” said Council Member Bruce Washburn at that meeting.
The Chazen Companies, which has been monitoring the site for the last two years, gave the town an estimate of $5,300 for the work involved in trapping the two beavers, including photography, documentation, permit applications from the DEC and the Army Corps of Engineers and studies to determine if getting rid of the animals would be effective in lowering the water table.
Another concern is that if the beaver activity stops suddenly and the dams are removed, more water could flow into the Rhinebeck Aerodrome.
“I’m willing to try the Havaharts,” said Washburn referring to live traps, “but from what I understand they might not work, so it might be wasted money.”
When the landfill was closed in 1997, a membrane was placed on top of the waste to contain it. That cap is “in good condition,” Russell Urban-Meade, a hydrogeologist with Chazen, who has been monitoring the landfill, told the board at its Dec. 10 meeting. “We’ve been keeping an eye on it for the past two years, and it seems sound, there’s no erosion, no wear.”
“Removing the beaver dams would lower the water table by the two or three feet that the dams have caused,” he added.
Another option being considered is a hydrology study, which would involve boring holes in the landfill to determine how much waste is above the water table and how much below. That would cost about $25,000, according to Council Member Elizabeth Spinzia.
“The problem is the garbage that is in the water, not the beaver,” Conservation Advisory Board Chair Jeff Romano told the board at its Dec. 10 meeting. “We really have to do the hydrology study to understand what’s going on here… That would give us a long-term solution to this problem.
Reading from the DEC report, he added, ‘Ammonia levels remain elevated well above the groundwater quality standard.’
“Ammonia is added to agricultural fields as a fertilizer,” Urban-Meade explained. “We’re not talking PCBs or petroleum.”
Council Member Joseph Gelb then suggested getting rid of the beavers, “and see what happens before we spend a lot of money drilling.”
Washburn told The Observer that until there is board agreement, the project is on hold.