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SPECIAL PROVISIONS (ROADWAY SURFACE) A.CONCRETE PAVEMENTS 1.Openings The opening made in a concrete pavement must be so located that no side is within three(3)feet of a construction joint. If the side of the opening is within three (3) feet of a construction joint, the concrete pavement must be removed to the joint. Before breaking the concrete, the slab must first be cut with a concrete saw to a depth of not less than two(2)inches,and the exact location thereof must be approved by the Hennepin County Highway Department. All broken concrete must be re- moved from site and disposed of. NO OPENINGS SHALL BE MADE IN PORTLAND CEMENT CONCRETE DURING WINTER MONTHS EXCEPT FOR EMERGEN- CIES. IF OPENING HAS TO BE MADE, ADJACENT EDGES WILL HAVE TO BE REMOVED ONE FOOT BEYOND ORIGINAL EXCAVATION THE FOLLOWING SPRING AND REPLACED BY A PERMANENT PATCH. 2. Backfill and Compaction After the excavation has been completed, the requirements for the backfill, i.e., kind of material, compaction,etc.,shall be the same as specified for the repairs made for"Trenching or Sub-surface Operations". (See item "C"below.) 3. Replacement of Concrete The concrete used for the final surface repair shall consist of high early strength concrete to meet Minnesota Highway Depart- ment Specification dated Jan. 1, 1968, No.2301.2-3A32 H.E. This concrete to be secured only from commercial plants which can furnish a mixture that is approved by the Hennepin County Highway Department.The final finish must be burlap dragged or broomed so that it will match the surface of the adjoining concrete slab, and cured with plastic paper.All construction joints shall be replaced. The fresh concrete patch shall be protected from all traffic contacts for at least 72 hours after it has been finished. B.HIGH-TYPE ASPHALTIC CONCRETE OR BITUMINOUS PAVEMENTS 1. Openings When necessary to cut openings in high-type asphaltic concrete surfaceci roadways, the size of opening and location thereof must conform to size and location specified in the permit, or to size specified by the Highway Department.When cutting the opening,the edges are to be cut in a straight line, and sides to be smooth and vertical. No ragged edges permitted.Cutting to be done with cutting wheel,jack-hammer,spades or similar approved tools.All excavated bituminous material to be removed from site and disposed of. 2. Backfill and Compaction After the excavation has been completed, the requirements for backfill. e., kind of material, compaction, etc.,shall be the same as specified for the repairs made for"Trenching or Sub-Surface Ope ations". (See item "C"below.) 3. Replacement of Concrete Base Use procedures listed under A-3 but do not saw edges and do not screec'the surface.Allow the concrete to cure for 24 hours before placing bituminous materials. 4. Prime and Tack Coat Before laying bituminous mixture a prime coat shall be applied to the gravel base at a rate not to exceed 0.3 gallon per square yard.The prime coat shall not be applied when moisture content of top three (3) inches of the sub-grade is more than 60%of optimum moisture. 5. Restoration of Blacktop All blacktop surfaces are to be restored as soon as possible after backfilling has been completed. Bituminous surfacing ma- terial may be obtained from most commercial"Blacktop"plants.The kind and grade must be approved by the Hennepin County Highway Department. Replacement of the bituminous material shall be m:3de in layers not to exceed two(2)inches in depth, each layerto be.compacted with an approved roller or vibrating tamper unless otherwise specially authorized. 6. Sealcoat All blacktop patches shall be sealed, overlapping the old surface at least six (6) inches and matching the aggregates of the existing seal. The bituminous material shall be applied at the rate of 0.2 to 0.3 of a gallon per square yard depending upon the cover aggregate to be replaced. 7. Damage to Blacktop Any blacktop area which has been scarred by equipment, lugs,cleats,teeth,etc., shall be replaced or repaired as directed by the County Highway Department. C.TRENCHING OR SUB-SURFACE OPERATIONS 1.Openings Trenches for conduits, water, steam, oil and gas pipes, sewers and other utilities placed within the right of way shall be lo- cated as approved by the Hennepin County Highway Department. Trenches for construction along the highway shall not be opened for a distance of more than 300 feet at any one time, unless especially authorized by the Hennepin County Highway Department. 2. Storage of Excavated Materials Excavated or other material shall be placed or stored on the side of the operation farthest from the traveled road unless otherwise authorized by the Highway Dept., and in such manner that there will be no interference with the flow of water in any gutter, drain, pipe,culvert, ditch or other waterway. 3. Backfill and Compaction After excavation has been completed,it may be refilled with the excavated material which has been removed,with the follow- ing exceptions: If the excavated material consists of mucky, soft or unstable soil, boulders, or large rock, it must be removed and disposed of outside the county right of way,and replaced with granular(sandy) material approved by the Highway Department. The refilling of the trench shall be done with Class 4 gravel or other approved material compacted by the ordinary compaction method and shall follow as rapidly as possible the placing of sub-surface structures and shall be completed in such manner as will conform to the earth shoulder or subgrade or as directed by the Hennepin County Highway Department. 4. Replacement of Gravel Base The gravel base shall be replaced with approved material and compacted. All compaction must be in accordance with the Minnesota Highway Specifications dated Jan. 1, 1968,Section 2105.3 "Ordinary Compaction".