- Use of artificial recharge to protect public supply wells from PFAS contamination
- Use of artificial recharge to enhance the production yield for public supply wells
- Aquifer assessment/groundwater development of new production well
- Numerical modeling of groundwater flow paths
- Permitting of artificial recharge
- Permitting of Surface Water Withdrawals -401 certificate
- Characterization of PFAS contamination - fate and transport
Challenge
Develop Artificial Recharge System to Protect Public Water Supply Production Wells from Groundwater Containing PFAS and Other Contaminants. GZA has completed a Groundwater Resource Assessment that focused on how to best utilize the groundwater resources available within the Pudding Hill Aquifer as a potable water supply for the City of Dover. This groundwater resource assessment grew out of the realization that the future viability of the Pudding Hill Aquifer as a drinking water resource for the City of Dover was being threatened by the migration of contaminated groundwater containing PFAS and other contaminants derived from the nearby Madbury Metals facility.
Solution
Solution: The ultimate purpose of this assessment was to maintain historic annual groundwater withdrawals from the Pudding Hill Aquifer, while (at the same time) protecting the Aquifer from the migration of MtBE, 1,4-Dioxane, PFOS, PFOA, and other contaminants toward the Production Well sites.
The following actions were taken to achieve these objectives:
- Establish the use of Artificial Recharge, using high flows from the nearby Bellamy River to enhance the recharge of the City’s existing Production Well and create a hydraulic mound to protect that well from the migration of groundwater containing PFAS and other contaminants
- Develop a new groundwater source in the Aquifer that could also benefit from the use of Artificial Recharge
- Modify the rate of groundwater withdrawals from the Aquifer at various well sites during different seasonal periods to lessen the migration of contaminants from the Madbury Metals facility
Benefit
As part of this Groundwater Resource Assessment, GZA installed two Artificial Recharge Basins and obtained the necessary funding and State/Federal permits to withdraw surface water from the Bellamy River to provide Artificial Recharge water to the Pudding Hill Aquifer. The Artificial Recharge Basins have been constructed using State and local funds.