grades of silica sand and gravel, meeting virtually every specification. 142 Prepared by Thomas P. Dolley [(703) 648–7710,
[email protected]] ... crystalline silica at quarry sites and in other industries that use materials containing it. Phased implementation of the ... Canada 2,500 2,500 France 9,310 9,300 Germany 7,500 7,500 India 11,900 12,000Web