Specifications include, but are not limited to: 4.3.1 The Contractor must furnish rock salt conforming to type 1, grade 1, as determined by American Society for Test and Materials (ASTM) standard D632, Standard Specification for Sodium Chloride. 4.3.2 The delivered rock salt must have a chemical composition with a minimum sodium chloride (NaCl) component of 95.0% (by weight). 4.3.3 The rock salt gradation must conform to the particle distribution listed in table 1 when tested using laboratory sieves. The sieves must be sized per ASTM E11, Standard Specification for Wire Cloth and Sieves for Testing Purposes. Table 1 – Rock Salt Gradation Percent Passing Sieve Size (by weight) 1/2 inch (12.5 mm) 100 3/8 inch (9.5 mm) 95 - 100 No. 4 (4.75 mm) 20 - 90 No. 8 (2.36 mm) 10 - 60 No. 30 (600 m) 0 - 15 4.3.4 The Contractor must furnish rock salt in bulk and treated with a non-toxic anticaking agent. The applied anti-caking agent must prevent caking and hardening for a period of not less than one year following delivery to the CTA irrespective of whether the rock salt is stored outdoors and uncovered. The anti-caking agent must equal or exceed the performance and quality of sodium ferrocyanide.
