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any similar exaggerated degree of treatment will not be required.

Intensity of cleanup shall be gradually diminished from the road prism construction outward to the cleanup limits or boundary designated by the Engineer, so as to effect a natural transition in treatment, and so as to avoid sharp demarcation between the artificial and the natural.

As a general guide, the first 20-foot width nearest the roadway shall have practically all small sticks and other loose particles removed, except those of approximately 1 inch or less in thickness or diameter. The second 20-foot width shall be cleaned of substantially all sticks and loose particles exceeding approximately 2 inches in thickness or diameter, and the third 20-foot width shall be cleared of substantially all sticks and loose particles exceeding approximately 3 inches in thickness or diameter.

Trees and snags designated for removal shall be cut flush with the ground. Stumps within the areas designated for cleanup shall also be cut flush with the ground.

Refuse from cleanup operations shall be disposed of as provided under section 201.

Method of Measurement 210.03 The area to be paid for will be the number of acres and fractions thereof or thousand square feet and fractions thereof, of land acceptably cleaned up as staked or designated by the Engineer and in accordance with these specifications. Acreage will be computed from dimensions measured horizontally.

Basis of Payment 210.04 The quantity determined as provided above will be paid for at the contract unit price per unit of measurement for the pay items listed below that are shown in the bid schedule, which price and payment will be full compensation for all work prescribed in this section, except for extra work of any rehandling of spoil materials due to delayed burning as ordered by the Engineer and not made necessary by fault or negligence of the Contractor.

Payment will be made under: Pay item

Pay unit 210(1) Roadside cleanup

Acre. 210(2) Roadside cleanup

1000 square feet.

Sections 211 through 299.-RESERVED

Section 300.

BASES

Section 301.-PLANT-MIX BITUMINOUS BASE

COURSE

Description 301.01 This work shall consist of aggregate and bituminous material mixed in a central plant and spread and compacted on a prepared surface in accordance with these specifications and in reasonably close conformity with the lines, grades, thicknesses and typical cross sections shown on the plans or established by the Engineer.

Materials 301.02 Composition of Mixtures. The bituminous base shall be composed of a mixture of aggregate, filler and hydrated lime if required, and bituminous material. The several aggregate fractions shall be sized, uniformly graded and combined in such proportions that the resulting composite blend meets the job-mix formula and index of retained strength determined in accordance with subsection 401.02. The amount of bituminous material to be added will be shown in the special provisions as a percentage by weight of the total aggregate.

301.03 Materials. The type and grade of bituminous material will be specified in the contract. The grade may be changed one step by the Engineer at no change in unit price. Application temperatures shall conform to subsection 702.05 for the material specified.

Bituminous material may be conditionally accepted at the source, subject to the provisions of clause 10 of the General Provisions. Job samples will be taken from the storage tanks specified in subsection 401.08(a) (2).

Materials shall conform to the requirements of the following subsections: Asphalt cements

702.01 Tars

702.02 Aggregate

703.03 Filler

703.15 Hydrated lime

712.03

Construction Requirements

301.04 General. The construction requirements shall be as prescribed in subsections 401.07 through 401.19, inclusive, of Section 401–Plant-Mix Pavements—General.

301.05 Surface Tolerance. The requirements of subsection 401.20 shall apply except that the variation of the surface from the testing edge of the straight edge between any two contacts with the surface shall, at no point, exceed 44 inch.

Method of Measurement

301.06 Plant-mix bituminous base course will be measured as prescribed in subsection 401.21.

Basis of Payment

301.07 The Accepted Quantities of Plant-Mix Bituminous. Base Course measured as provided above, will be paid for at the contract unit price per ton for the bituminous base mixture and, if included in the bid schedule as a pay item, per ton or gallon for the bituminous material complete in place, which prices and payment will be full compensation for the work of this section. Payment will be made under: Pay item

Pay unit 301(1) Plant-mix bituminous base course (asphalt)

Ton. 301(2) Plant-mix bituminous base course (tar)

Ton. 301(3) Asphalt cement, grade

Ton. 301(4) Asphalt cement, grade

Gallon. 301(5) Tar, grade RT

Ton. 301 (6) Tar, grade RT

Gallon. Letter suffixes will be added to pay item numbers 301 (1) and 301 (2) to designate alternative types of aggregates to be bid on.

Section 302.-RESERVED

Section 303.-RESERVED

Section 304.-AGGREGATE BASE COURSE

Description 304.01 This work shall consist of furnishing and placing one or more courses of aggregate and additives if required, on a prepared surface in accordance with these specifications, in reasonably close conformity with the lines, grades, thicknesses and typical cross sections shown on the plans or established by the Engineer.

Materials

304.02 Aggregate. The aggregates shall meet the requirements of subsection 703.06.

When the stationary plant method is used the aggregate will be tested for acceptance immediately following mixing based on periodic samples taken from the pug mill output. When a road mix method is used, the aggregate will be tested for acceptance after necessary blending and before laying based on samples taken from the combined windrow for each lift.

304.03 Chemical Additives. Chemical additives shall meet the requirements of the following subsections: Calcium chloride

712.02 Sodium chloride

712.02 Hydrated lime

712.03

Construction Requirements 304.04 Preparation of Roadbed. The roadbed, including shoulders, shall be constructed, prepared, and finished as provided under section 207 before placing aggregate base course material.

304.05 Mixing and Placing. Unless otherwise specified, the Contractor may mix the base course by any one of the three following methods and if required, shall incorporate the additive shown on the plans.

(a) Stationary plant method.The base course material and water shall be mixed in an approved mixer. Water shall be added during the mixing operation in the amount necessary to provide the moisture content for compacting to the specified density. After mixing, the base material shall be transported to the job site while it contains the proper moisture content and shall be placed on the roadbed by means of an approved aggregate spreader.

(b) Travel plant method. After the material for each layer of base course has been placed through an aggregate

spreader or windrow sizing device the base shall be uniformly mixed by a traveling mixing plant. During the mixing, water shall be added in an amount sufficient to provide the necessary moisture content for compacting.

(c) Road mix method.After material for each layer of base course has been placed, the materials shall be mixed while at required moisture content by means of motor graders or other approved equipment until the mixture is uniform throughout.

The base material shall be placed on the prepared roadbed and compacted in layers of the thickness shown on the plans. When more than one layer is required, each layer shall be shaped and compacted before the succeeding layer is placed. If the Contractor elects to produce and stockpile aggregates prior to placement on the roadbed, the aggregates shall be stockpiled in accordance with the requirements of section 413.

The placing of material shall begin at the point designated by the Engineer. Placing shall be from spreader boxes or from vehicles especially equipped to distribute the material in a continuous uniform layer or windrow. The layer or windrow shall be of such size that when spread and compacted, making due allowance for any blending material that is to be added on the road, the finished layer shall be in reasonably close conformity to the nominal thickness shown on the plans.

When hauling is done over previously placed material, hauling equipment shall be dispersed uniformly over the entire surface of the previously constructed layer, to minimize rutting or uneven compaction.

304.06 Spreading and Compacting. When uniformly mixed, the mixture shall be spread smoothly for compaction to the nominal plan thickness.

Immediately following final spreading and smoothing, each layer shall be compacted to the full width by means of smooth-wheel power rollers, pneumatic-tired rollers or other approved compaction equipment. Rolling shall progress gradually from the sides to the center, parallel to the centerline of the road, and shall continue until all the surface has been rolled. Any irregularities or depressions that develop shall be corrected by loosening the material at these places and adding or removing material until the surface is smooth and uniform. Along curbs, headers, and walls, and at all places not accessible to the roller, the base material shall be compacted thoroughly with approved tampers or compactors. The material shall be both bladed and rolled until a smooth, even surface has been obtained.

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