MG-30 (calcium chloride/magnesium hydroxide) is sprayed yearly on our gravel road. It is an approved product through Alberta Transportation, and is becoming more of the industry standard because it is more moderate on the soil and vegetation than straight calcium chloride. Kortech, our contractor, says it is less corrosive than rain water. It does contain some calcium chloride, but the magnesium hydroxide acts as an inhibitor in the product.
MG 30 also has road surface stabilization characteristics that bind aggregate materials, increasing grade strength and thus keeping aggregate on the road. MG 30 has also proven to help reduce washboard, grader maintenance and the frequency for gravelling.