Before the street is open to traffic, the surface must be treated with a coat of asphaltic cement, applied by hand or machinery, so that the entire surface is covered with at least one-third of a gallon of asphaltic cement to the square yard. The asphaltic cement used for the surface treatment must be the product of a standard asphaltic oil or native liquid asphalt. The entire surface must then be covered with sand, gravel or limestone screenings. If limestone screenings are used they must not contain more than 5 percent of material that will pass an 80-mesh screen. If after the street has been opened to traffic there occurs a deficiency of sand during the period of the first 6 months, the contractor upon notification must resand same.