§ 801-44. Roadway foundation.

A. 

A minimum of 12 inches of clean gravel, as approved by the engineer, shall be deposited in not more than six-inch layers for the full width of the way so as to form a roadway foundation which shall be at all points parallel to the finished grade of the roadway surface. The gravel shall be compacted to 95% of the maximum dry density as determined by the Modified Proctor Test, in accordance with ASTMD-1557, Method D. The gravel shall consist of processed gravel for subbase meeting the Massachusetts DPW Specification Number M1.03.1 to the following gradation:

	Sieve Size	Percent Passing By Weight
	3 inches	100
	1 1/2 inches	70-100
	3/4 inches	50-85
	No. 4	30-60
	No. 200	0-5

B. 

The engineer will inspect the roadway foundation after the compaction of each six-inch layer and after the approval of the completed foundation.

C. 

Where it is acceptable to both the applicant's engineer and the Planning Board's engineer, an alternate roadway foundation may be utilized consisting of a minimum of 12 inches of reclaimed pavement borrow material (reclaimed asphalt). In general the use of dense graded crushed stone will only be permitted where the underlying material is suitable, well draining, and structurally sound. The dense graded crushed stone shall conform to the following gradation:

	Reclaimed Pavement Borrow Material
	Sieve Size	Percent Passing By Weight
	2 inches	100
	1 1/2 inches	70-100
	3/4 inch	50-85
	No. 4	30-55
	No. 50	8-24
	No. 200	3-10

D. 

The subgrade and each six-inch layer of gravel shall each be compacted with a minimum of three passes of a vibratory roller. Additional passes shall be made as required to achieve the 95% density required.