Specifications include, but are not limited to: The New Hampshire Geological Survey (NHGS) within the New Hampshire Department of Environmental Services (NHDES) is seeking bids for the installation of three (3) groundwater monitoring wells to be installed in Colebrook, Franklin, and Concord, New Hampshire. The newly installed wells will replace existing monitoring wells in the New Hampshire Groundwater Level Monitoring Network that have been damaged or compromised. The preferred methods for monitoring well installation will be using 4-1/4” ID (inside diameter) Hollow Stem Augers. Final depths for each groundwater monitoring well are anticipated to be: Colebrook to a depth of 50 feet below ground surface (bgs), Franklin to a depth of 50 feet bgs, and Concord to a depth of 40 feet bgs. The final well depths will be based on field conditions and determined on site. Groundwater monitoring wells are to be constructed with schedule 40, 2-inch ID PVC riser and well screen. Filter pack sand is to be used to fill the bore annulus around the screen to a minimum of two feet above the top of the screen. A bentonite seal will be placed above the filter pack with a minimum thickness of 2-feet. A steel well protective casing will be installed and cemented at the ground surface to protect each well. Once installed, each well will be pumped to develop the well filter pack and remove fine sediments from the well.
