Penetration macadam surface course shall include the construction, on a previously prepared base course, of a pavement surface course of bituminous bound macadam at the prescribed locations, to the prescribed lines, grades, and dimensions, and in accordance with the plans and specifications.
A. 
The crushed stone shall be one-and-one-half-inch, five-eighths-inch or one-half-inch, and three-eighths-inch sizes, and shall conform to the requirements therefor as set forth in Article II of this chapter.
B. 
The bituminous binder shall be tar R-11 or R-12 or asphalt cement grade OA-4 or NA-4, conforming to the requirements of Article II of this chapter.
A. 
The surface course shall be constructed on a base course which shall be dry, free from frost, clean, free from loose or adhering foreign materials, and properly finished at the time the surface course is placed thereon. All rolling shall be done with three-wheel power-driven rollers having a load of not less than 330 pounds per linear inch of tread of rear wheels. The rolling shall be first parallel to the axis of the pavement starting at the edges and working toward the center, and subsequently it shall be diagonal as well as parallel to the axis. All parts of the pavement shall be rolled by the rear wheels.
B. 
The one-and-one-half-inch size crushed stone shall be spread on the base course to the proper depth. It may be spread directly from a vehicle approved for the purpose, and shall not be dumped in piles within the area on which it is to be spread. After being spread, the stone shall be kept clean and protected from coatings of foreign materials until the bituminous binder is applied. No more than sufficient stone for a day's work shall be spread in advance of rolling and the application of the bituminous binder, unless otherwise approved by the Borough Engineer. The stone shall be rolled until thoroughly compacted to the proper grade and contour, and then the surface shall not be used for any purpose until the bituminous binder is being applied. The bituminous binder material shall then be applied, as hereafter described, by means of motor-driven pressure distributors of modern design, in good mechanical condition, of not less than 600 gallons' capacity, capable of producing a sufficient pressure to apply the bituminous material in the proper manner, and equipped with spraying manifolds of various lengths as may be approved by the Borough Engineer. After the required number of applications of bituminous binder and cover materials have been made as hereinafter specified, any places found deficient in bituminous binder, or insufficiently coated or bound, or below the required grade shall have additional binder and cover material applied by hand and shall be rerolled, or shall be repaired as the Borough Engineer may direct. If, in the opinion of the Borough Engineer, it is desirable to roll the surface after it is opened to the traffic, this shall be done when and as directed by him.
C. 
The finished surface shall be firmly bound together, free from improperly consolidated spots, porous places, depressions and projections of more than 1/4 inch in 10 feet, and an excess of three-eighths-inch size stone, and shall be at the proper grade and crown.
A. 
When the bituminous binder is being applied, its temperature in degrees Fahrenheit shall be as follows:
Air Temperature
(degrees Fahrenheit)
Asphalt Cement
(degrees Fahrenheit)
Tar
(degrees Fahrenheit)
50 – 65
325 – 350
225 – 250
Over 65
300 – 350
185 – 250
B. 
The bituminous binder shall be applied only when the atmospheric temperature is above 50° F. and has remained about 40° F. for the preceding eight hours, and when the stone surfaces are dry for the full depth of the course. The first application shall be at the rate of 1.75 to 2.25 gallons per square yard of surface. While the bituminous binder is still liquid, it shall be covered with a uniform layer of clean, dry five-eighths-inch or one-half-inch size crushed stone, just sufficient to fill the surface voids, and the surface shall then be rolled until the material is thoroughly embedded in the bituminous binder and anchored in place and there is no perceptible movement under the roller. When the bituminous binder sticks to the roller wheels, additional stone shall be spread.
C. 
Immediately after the completion of the rolling, a second application shall be made of the bituminous binder at the rate of from 0.5 to 0.75 gallons per square yard, and it shall be covered with a layer of three-eighths-inch size crushed stone. The surface shall be rolled until it has the proper density, after which it shall be opened to traffic. If the bituminous binder appears on the surface, additional three-eighths-inch size crushed stone shall be spread so as to keep the entire surface covered for a period of not less than 30 days.
D. 
After 30 to 60 days' use by traffic and at such time as the Borough Engineer may approve, the surface shall be swept thoroughly and all dust and dirt shall be removed. A third application of bituminous binder shall then be made at the rate of not less than 0.33 gallons per square yard, and it shall be covered immediately with three-eighths-inch size crushed stone at the rate of not less than 25 pounds per square yard of surface, and immediately thereafter the surface shall be thoroughly rolled.