(A) Temporary grade surfaces. Where excavations are made in paved areas, the surface shall be replaced with a temporary gravel surface. Gravel shall be placed deep enough to provide a minimum of six inches below the bottom of the asphalt or concrete surface. Normally, this will require six inches of gravel for asphalt surfaces, 12 inches of gravel for concrete and a concrete base for asphalt wearing surfaces. Gravel shall be placed in the trench at the time it is backfilled. Temporary gravel surface shall be maintained by blading, sprinkling, rolling and adding gravel to maintain a safe, uniform surface satisfactory to the Supervisor until the final surface is laid. Excess material shall be removed from the premises immediately. Material for use on temporary gravel surfaces shall be obtained from sound, tough, durable gravel or rock meeting the requirements for grading outlined in the County Road Specifications for untreated base course.
(B) Asphalt (HMA) surfaces. The exposed edges of existing pavement shall be primed with Type MC-1 asphalt material or better. The Supervisor shall approve the type, grade and mixture of the asphalt to be used for road surface replacement. The thickness shall be equal to the adjacent surface thickness but not less than three inches. The complete surface shall not deviate more than one-half inch between old and new work. Refer to the County Specifications for additional mix requirements.
(C) Concrete surfaces. The sub-base for concrete surfaces shall be sprinkled with clean water just before placing the concrete. Joints and surfaces shall be made to match the original surfaces. The thickness of concrete shall be equal to the adjacent concrete, but in no case less than six inches thick. The Supervisor will approve the mixing, cement, water content, proportion, placement and curing of the concrete. In no case shall the concrete have less compressive strength than four pounds per square inch at the end of 28 days, and the classification shall be Class AA(AE).
(D) Maintenance. The maintenance of all concrete surfaces shall be the responsibility of the permittee. If the concrete structure is not maintained and interferes with the normal maintenance of the road, it will be removed at the permittee’s expense.
(E) Concrete base, asphalt wearing surfaces. This type of surfacing shall be constructed as described above.
(F) Gravel surfaces. Trenches excavated through gravel surfaces, such as gravel roads, shoulders and unpaved driveways, shall have six inches of road base gravel restored and maintained. The requirements for the road base can be found below and in the County Standards and Specifications. The Permittee is responsible for the maintenance of trenches across the road for one-year minimum, and all materials and compaction shall comply with County Road Specifications.
(Ord. 2023-4-1, passed 4-10-2023)