Over the years, during our audit work, we do randomly pick sites to audit, and we go back and look at the environmental assessments and the approaches that the government is taking.
I couldn't tell you if we looked at any this year, but I know from the many years that I've been involved in the public accounts of Canada that there are a lot of experts involved who decide whether not touching the unexploded ordnance is the safest choice, that it is buried deep enough and that it doesn't cause harm to the community, anyone or the environment around it.
Really, that question is probably best asked to the Department of National Defence, which manages these sites. The department could provide you with details as to what criteria it uses to make those assessments.