Bedrock Well Testing Update
The Chittenden Solid Waste District contracted with a local environmental consulting firm to conduct a groundwater monitoring study in the summer of 2009 to determine the likelihood of contaminants from proposed and existing landfills at our Williston facilities penetrating the bedrock aquifer and entering nearby drinking water wells. Results of this study indicate that there is little likelihood of that occurring due to existing landfill leachate management programs; a naturally occurring, highly impervious geologic barrier of silts and clays between the landfill bases and the bedrock aquifer; and the determination that the direction of groundwater flow in the bedrock aquifer is to the north and away from the nearby wells.
CSWD's decision to have this study conducted arose when homeowners on Ledgewood Drive in Williston approached CSWD to request that their drinking water be tested due to concerns about possible contamination from the old landfills on Redmond Road, which are located about two-thirds of a mile north of the nearest homeowner wells. Note that these landfills have been properly capped and closed since 1995, and the water quality around them is intensively monitored under the requirements of their post-closure plan.
Prior to running the study, CSWD met with its landfill design consultant (Shaw Environmental); Heindel & Noyes (H&N), a firm specializing in hydrogeology and environmental engineering; and two State of Vermont Agency of Natural Resources environmental engineers to evaluate the likelihood of contamination from the old landfills impacting any existing drinking water wells. Based on indications that the groundwater flows north from the closed landfills--away from nearby wells--the conclusion was that contamination would be highly unlikely.
To be certain that leachate was indeed not impacting existing drinking wells in the vicinity, CSWD instructed H&N to monitor a selection of wells that would yield a representative understanding of the area's water quality and groundwater movement.
The documents below include the full report of H&N's 2009 study. Click on the name of any document to view it as a pdf file. Printouts may be viewed at the CSWD Administrative Offices (1021 Redmond Road, Williston), the Williston Town Office (7900 Williston Road), and the Dorothy Alling Memorial Library (21 Library Lane, Williston).
If you have any questions about the study, please contact CSWD General Manager Tom Moreau at 872-8100.
2004 Orthophoto
Summary Table
Bedrock Geology
Surficial Geology
Target Wells
USGS Map
Evaluation Report
Appendix 1, figures 1-4
Williston Host Town Fees
Where have the voters of the Town of Williston decided to spend their host town fees? Firefighter equipment, pedestrian improvements, scholarships, recreational upgrades . . . for a complete list, click here.
What are the environmental and societal costs of trucking waste to distant landfills? Read the full report.
Comments or questions about the regional landfill may be submitted to:
Tom Moreau, General Manager
Chittenden Solid Waste District
1021 Redmond Road
Williston, VT 05495
Phone: (802) 872-8100
Fax: (802) 878-5787
Email: tmoreau@cswd.net