South Bruce is ideal site for DGR, says reader

To the Editor:
RE: “DGR for used nuclear fuel should not be sited near Great Lakes, says writer”

I read with some agreement, the letter from Laura Cardinal about the DGR storage site. The agreement comes from the comment about the necessity of accurate scientific and engineering testing, and the need for prototypes.

In some ways, however, a prototype has been in place for some time. The world's largest salt mine is located at Goderich, and the mine workings extend well beyond seven kilometres under Lake Huron.

The salt comes from the horizon of rock aptly named the Salina Formation. The limestone that is to serve as the storage site for the nuclear waste occurs about 200 metres, below the base of the Salina Formation.

The underground workings of the salt mine at Goderich have been in operation for several decades. I stand to be corrected, but I am not aware of any significant or dangerous contamination of the salt horizons or mine workings into the fresh water of Lake Huron, well above. The various layers of the sedimentary rock in southwestern Ontario, are reasonably consistent and continuous, well documented, and easily verified.

The author notes that "we have a specific set of our own circumstances, from rock type, water flow, arrangement of tectonic plates, etc.," and it is correct that as she points out, it is rather irrelevant to use other sites around the world as examples.

This is exactly the point. The rock type is a very dense and non-porous limestone (I don't know where various references to porous limestone come from; it's not this rock). Testing has been extensively done, and of course, will be done further before any site development is considered.

From the reports I have read, and as I interpret the engineering data, it takes an order of a million years or so for fluid to move through this particular limestone a distance of one metre. As far as the tectonic plate arrangement is concerned, so far studies have shown no tectonic movement in the past few hundred-million years.

So by all means, focus on rock type, water flow, and tectonics. You will find the site in South Bruce is the absolute envy of industry experts around the globe.

I have a great affection for this region, and its natural setting. We live here now about 10 months of the year (we are mostly in Hamilton the rest of the time).

My first calling was as a geologist. I have two degrees in that science, and enjoyed half of that working time with the Engineering and Terrain Geology Section of the Ontario Geological Survey. I only add this to establish some credibility.

My main concern is for the environment. I don't believe you can get any safer than the plan that exists.

I am concerned for many reasons with transporting the material to northern Ontario or elsewhere for permanent storage. But that is another story ...

Bob Geddes
Huron-Kinloss Township