Open letter to the select committee regarding the risks and benefits of hydraulic fracturing:
North America is the first continent where hydraulic fracturing will be used in areas with permafrost. In the Peel watershed north of the Wernecke Mountains we encounter continuous permafrost. The depth of this permafrost can be anywhere between 50 to 200 metres, depending on the location, the aspect and the slope. Hydraulic fracturing has been unprecedented in these areas, and shall be used in Alaska, Yukon and the N.W.T.
The first thought that comes to mind in terms of permafrost and drilling is the question of well case integrity. According to Dr. Gilles Wendling, an expert in hydrogeology, well case integrity has been questionable in areas without permafrost. The process of proper bonding between the cement casing and the surrounding soil is very challenging in 1,000 to 5,000 metres under the Earth surface. And well integrity becomes even more unpredictable if you throw permafrost of unknown depth into the mix.
Escaping gases and fluids can cause permafrost melting in the immediate vicinity of the well. This process can create pathways for water and additional permafrost melting. Another unknown is whether the high temperature gradient between the hot gas and the frozen ground can be mitigated enough to avoid permafrost melting.
An even more troubling question is how the 4 million gallons of inserted fracturing fluid will behave under the thick permafrost layer in places like Eagle Plains.
The experience has been that an average of maximal 30 per cent of the fracturing fluid can be recaptured. Confined in upwards movement the fluid will work its way into the cracks in the rocks and permafrost, or it will mix with the deep, old formation water and join the deep underground water current.
There is no research available concerning the water quality and quantity in areas with continuous permafrost in the Yukon. Even the depth of the permafrost around Eagle Plains is greatly unknown. Hydraulic fracturing in these areas of the Yukon can only be compared with a blind cut on the operating table.
In this case of unprecedented scientific uncertainty, our neighbors in the N.W.T. will have to be consulted prior to operating at Eagle Plains or the Peel Plateau. The Peel River’s water quality and quantity has been protected under the Mackenzie River Basin Transboundary Waters Master Agreement. And I do not believe that any other river system in the North could supply the huge water quantity necessary for hydraulic fracturing.
Angela Sabo
Whitehorse