(A) Roadways.
(1) General requirements. All grading, gravel base, concrete curb and gutter, bituminous curb and bituminous paving shall conform to the current requirements of the Minnesota Department of Transportation Standard Specifications for Highway Construction.
(2) Excavation and embankment.
(a) All operations are to be done in accordance with MNDOT Specifications No. 2105. All compaction will be done by the ordinary compaction method except as follows at the County Engineer’s option, density tests may be taken to evaluate the compaction achieved. Where density tests are taken to evaluate the compaction, the fill shall meet the requirements of MNDOT Specification No. 2105 for embankment compaction by the specified density methods. In areas of cut where no utility construction is proposed, the top 12 inches below the finished subgrade shall be excavated and recompacted to a density of not less than 100% of maximum density.
(b) Granular borrow and select granular borrow are to be the requirements of MNDOT Specification No. 3149, maximum particle size to be six inches in diameter.
(3) Gravel surface, gravel base, bituminous base, bituminous wearing course and bituminous seal coat.
(a) Gravel surface and base shall be class 5 or class 2 aggregate meeting the requirements of MNDOT Specification No. 3138 unless otherwise approved by the County Engineer.
(b) Bituminous base and wearing course construction is to meet the requirements of MNDOT Specification Nos. 2331 and 2341, respectively. Recycled bituminous base MNDOT Specification No. 2332 is also permitted.
(c) Bituminous seal coat shall be constructed in accordance with MNDOT Specification No. 2356. The bituminous material and aggregate type are to be determined based on traffic volumes and service conditions.
(4) Staged construction.
(a) All roads constructed in conjunction with sanitary sewer, watermain and/or storm sewer improvements are to be completed over the course of two construction seasons. The initial phase of construction shall include the complete installation of the underground utilities, gravel base, curb and gutter and bituminous base course within the roadway areas. The bituminous wearing course shall be completed after at least one winter but before the third winter.
(b) The minimum thickness of bituminous base MNDOT 2331 shall be two inches during the interim period.
(c) All manholes and valve boxes are to be installed in the bituminous base course and left ½-inch below the surface throughout the winter and then raised to ½-inch below the final surface prior to placing the bituminous wearing course.
(B) Utility construction restoration.
(1) General requirements. The utilities being referred to pertain to sanitary sewers, storm sewers and watermains. The following requirements are to pertain to each utility unless specifically noted.
(2) Backfilling and compaction.
(a) Utility trenches are to be backfilled in lifts approximately eight inches in thickness and mechanically compacted to 100% of maximum density in the upper three feet and 95% of maximum density below the upper three feet in all roadway areas. Soil compaction shall be in accordance with MNDOT Specification No. 2105 for compaction by the specified density method. The zone around the pipe shall be bedded and compacted to industry standards depending upon the pipe material and depth of installation.
(b) Where utilities are installed in easement areas, the top 12 inches shall be compacted to 100% maximum density and the area below the top 12 inches to 95% maximum density.
(c) The compaction requirements for the utilities include all branch services and stubs as outlined above.
(C) General restoration.
(1) General requirements. All areas disturbed by construction are to be restored to a condition equal to or better than what existed prior to construction.
(2) Sod. Sod shall be required where improved lawn areas are disturbed. Sod shall be densely rooted blue grass or other approved grasses free of noxious weeds and objectionable grasses. After placement, sod shall be pressed into the underlying soil by rolling or tamping. Pegging of sod shall be required in ditches and drainage channels and on steeper slopes.
(3) Seed.
(a) Seed shall be required where construction activities disturb unimproved areas. Seed and application are to conform to mixture #700 under Minnesota Department of Transportation Specification Nos. 2575 and 3876. Seed shall be applied uniformly at 75 pounds per acre.
(b) In certain areas, seed and mulching may be required. All mulching shall be done in accordance with MNDOT Specification Nos. 2575 and 3882 for Type 1 mulch.
(c) In areas of steep slopes, seeding with wood fiber blankets may be substituted for sod. All such work shall be done in accordance with MNDOT Specification Nos. 2575, 3876 and 3885 for wood fiber blankets.
(4) Topsoil. Topsoil shall be applied to the restoration areas prior to sod or seed. Topsoil shall be pulverized black dirt acceptable to the Engineer and shall be spread to a compacted thickness of three inches.
(5) Maintenance of sodded and seeded areas. All sodded and seeded areas are to be watered and maintained in a satisfactory condition until acceptance of that portion of the work. Sod and seed that dies, or washes out, prior to acceptance are to be replaced by the developer.
(D) Debris and waste. Waste materials of any kind shall not be buried in any land or left deposited on any lot or road.