Artesian environmental well casings in cold regions pose a number of problems:
- Icing around the wellhead may pose safety concerns
- The true head cannot be measured without plugging the casing
- If the casing is plugged on the surface, freezing action may rupture the casing even if it is steel, almost certainly if it is PVC.
The Sub-frost Artesian Environmental Packer has features which address these problems and others. It is a mechanical packer which seals at depth (typically 3 m) by tightening screws on the surface. A top cable seal and through-pipe permit a piezometer located below the packer to be monitored with the packer in place.
A flange prevents the packer from accidental loss down the casing. The annulus above the seal may be purged to prevent freezing in that area using antifreeze or compressed air via a notch in the flange. The entire assembly is made of stainless steel and nitrile rubber, so corrosive effects of brines are minimized.