June 21st, 2018
After 36 years Terry W. Hennigar, P.Eng., FEC, who spent many months on Sable Island in the 1970’s researching the hydrogeology of Sable Island, returned this past summer to survey the island in an attempt to select wells for monitoring the quality of groundwater on the island. This work was supported by Parks Canada as an initiative of developing a long term monitoring program for the new Sable Island National Park Reserve.
The following is a summary of findings from the reconnaissance work carried out on Sable Island during August 2013:
1. Significant changes in the landscape of the island compared to the 1970s were noted. The areas of most observed changes were near the Old Mobil Base Camp on the West Spit and in the Green Plains.
2. Most of the exploratory test holes drilled in 1971 could not be located because of sand accumulations to the extent of several meters or more.
3. Two of the three former groundwater observation wells that were installed and instrumented during the early 1970s by Nova Scotia Environment were located, but were found to be inoperable as monitoring wells.
4. Implementation of a groundwater observation well network, for monitoring water levels and quality, requires new, proper well construction and instrumentation installation with digital pressure transducers.
5. Operation of a groundwater observation well network will require regular well maintenance and monitoring of instrumentation operation on a regular schedule.
6. A program will be required to assure the wells are functioning and easily located for access, servicing, and data retrieval.
Mr. Hennigar made the following recommendations for establishing and operating a groundwater observation well network on Sable Island:
1. New wells should be constructed and instrumented to implement a new groundwater observation well network for monitoring water levels and quality.
2. A dedicated observation well maintenance and monitoring program will be required to assure the wells are functioning and easily accessed for servicing.
3. New groundwater observation wells should be located in the area of the Main Station water supply and in the Green Plains.
4. The hydrogeologic setting of a selected number of ponds should be investigated to determine their status as perched or water table ponds.
Mr. Hennigar provided his professional services for free; Rae Anne LaPlante (a videographer from British Columbia), Friends of Sable Island Society and Parks Canada collaborated to cover his travel and living costs for the trip to Sable Island.