All cement shall conform to ASTM C150-59. All cement shall be dry and free from hydration of “set” at its time of use. (Ord. 383 § 280, 1974).

All sand shall be fine granular material resulting from the natural disintegration of rock and shall be free from injurious amounts of oil, mica, clay, and other deleterious substances. All sand shall conform with the applicable county engineering and general services department specifications for similar use. (Ord. 383 § 281, 1974).

All rock and gravel for use in concrete shall be clean, hard, tough, durable, properly graded, and uncoated pieces, free from injurious amounts of soft, friable, thin, elongated or laminated pieces, alkali, oil, organic, or other deleterious substances. All rock and gravel shall conform with the applicable county engineering and general services department specifications for similar use. (Ord. 383 § 282, 1974).

All water used in concrete or grout shall be clean and free from oil or vegetable matter and sulfur compounds. (Ord. 383 § 283, 1974).

All concrete used for thrust blocks shall develop an ultimate compressive strength of two thousand psi at twenty-eight days, in accordance with ASTM C39-56T. (Ord. 383 § 284, 1974).