TransGas advances scheduled shutdown to facilitate groundwater researchThe Saskatchewan Watershed Authority (SWA) has asked TransGas to begin a controlled shutdown of its operations near Vanscoy to allow further research to be conducted regarding public concerns about groundwater levels in the Grandora area. The company had originally scheduled a temporary shutdown for March 2005, but has agreed to move the timing up by approximately 15 weeks.
At the direction of the SWA, TransGas will drill additional observation wells and will add additional monitoring equipment at several existing wells. It has also agreed to suspend its pumping operations about one week after the additional monitors are in place, so that accurate comparisons of data can be made during operation and non-operation.
TransGas has been using groundwater from the Tyner Valley aquifer to dissolve salt and create underground caverns for the storage of natural gas to meet the energy needs of west-central Saskatchewan.
Nolan Shaheen, the SWA's director of groundwater management, said the original request for a groundwater allocation was approved on the basis of results from test drilling and modeling done by professional hydrogeologists. A condition of the company's allocation, he noted, requires TransGas to mitigate impacts to existing users.
"However, monitoring data collected since the pumping started in January shows the water level declines in the Tyner Valley aquifer were greater than suggested by the original modeling. Users from the Grandora area, who get their water from other aquifers, have also claimed that water levels in their wells have dropped by several metres since TransGas started pumping," Shaheen explained.
At this point, he continued, it is not clear whether the water supply problems are due to the TransGas operation or some other cause. "Temporarily suspending the TransGas operation by advancing the scheduled shutdown and collecting more data will allow us to make a better water management decision."
The SWA will have the results of the latest research by late January. If the results indicate that the TransGas operations are causing the problems in the Grandora area, the Authority could direct the company to reduce the rate of water use or could suspend the allocation altogether.
If the overall use is deemed sustainable, TransGas may be allowed to resume operations at their current level. The company would be required to mitigate water wells of any other users who have suffered adverse impacts to their water supply as a result of its operations.
In compliance with the terms of its approval, TransGas has already completed mitigation on 61 local wells. This has generally involved lowering or replacing of pumps, but in some instances has required drilling new wells.
More information is available from Nolan Shaheen of the Saskatchewan Watershed Authority, 306/694-3963.