I'm not sure what kind of gravel it is - but it was put in with the assistance of the MNR in 2011 so I'm sure it's safe for them. They took out the old stuff and power washed the ledge. The year before the kids showed symptoms of illness so it was decided to clean and replace the gravel on the ledge as it hadn't been done since 2002.
Oh it definitely works, just looks a bit jagged! It's all good! Thanks Carly and Alison!
