PART C - EARTHWORK
ITEM 100 - CLEARING AND GRUBBING
100.1 Description
This item shall consist of clearing, grubbing, removing and disposing all vegetation and debris as designated in the Contract, except those objects that are designated to remain in place or are to be removed in consonance with other provisions of this Specification. The work shall also include the preservation from injury or defacement of all objects designated to remain.
100.2 Construction Requirements
100.2.1 General
The Engineer will establish the limits of work and designate all trees, shrubs, plants and other things to remain. The Contractor shall preserve all objects designated to remain. Paint required for cut or scarred surface of trees or shrubs selected for retention shall be an approved asphaltum base paint prepared especially for tree surgery.
Clearing shall extend one (1) meter beyond the toe of the fill slopes or beyond rounding of cut slopes as the case maybe for the entire length of the project unless otherwise shown on the plans or as directed by the Engineer and provided it is within the right of way limits of the project, with the exception of trees under the jurisdiction of the Forest Management Bureau (FMB).
100.2.2 Clearing and Grubbing
All surface objects and all trees, stumps, roots and other protruding obstructions, not designated to remain, shall be cleared and/or grubbed, including mowed as required, except as provided below:.
- Removal of undisturbed stumps and roots and nonperishable solid objects with a minimum depth of one (1) meter below subgrade or slope of embankment will not be required.
- In areas outside of the grading limits of cut and embankment areas, stumps and nonperishable solid objects shall be cut off not more than 150 mm above the ground line or low water level.
- In areas to be rounded at the top of cut slopes, stumps shall be cut off flush with or below the surface of the final slope line.
- Grubbing of pits, channel changes and ditches will be required only to the depth necessitated by the proposed excavation within such areas.
- In areas covered by cogon/talahib, wild grass and other vegetations, top soil shall be cut to a maximum depth of 150mm below the original ground surface or as designated by the Engineer, and disposed outside the clear.ing and grubbing limits as indicated in the typical roadway section.
Except in areas to be excavated, stump holes and other holes frorn which obstructions are removed shall be backfilled with suitable material and compacted to the required density.
If .perishable material is burned, it shall be burned under the constant care of component watchmen at such times and in such a manner that the surrounding vegetation, other adjacent property, or anything designated to remain on. the right of way will not be jeopardized. If permitted, burning shall be done in accordance with applicable laws, ordinances, and regulation.
The Contractor shall use high intensity burning procedures, (i.e., incinerators, high stacking or pit and ditch burning with forced air supplements) that produce intense burning with little or no visible smoke emission during the burning process. At the conclusion of each burning session, the fire shall be completely extinguished so that no smoldering debris remains.
In the event that the Contractor is directed by the Engineer not to start burning operations or to suspend such operations because of hazardous weather conditions, material to be burned which interferes with subsequent construction operations shall be moved by the Contractor to temporary locations clear of construction operations and later, if directed by the Engineer, shall be placed on a designated spot and burned.
Materials and debris which cannot be burned and perishable materials may be disposed off by methods and at locations approved by the Engineer, on or off the project. If disposal is by burying, the debris shall be placed in layers with the material so disturbed to avoid nesting. Each layer shall be covered or mixed with earth material by the land-fill method to fill all voids. The top layer of material buried shall be covered with at least 300 mm of earth or other approved material and shall be graded, shaped and compacted to present a pleasing appearance. If the disposal location is off the project, the Contractor shall make all necessary arrangements with property owners in writing for obtaining suitable disposal locations which are outside the limits of view from the project. The cost involved shall be included in the unit bid price. A copy of such agreement shall be furnished to the Engineer. The disposal areas shall be seeded, fertilized and mulched at the Contractor's expense.
Woody material may be disposed off by chipping. The wood chips may be used for mulch, slope erosion control or may be uniformly spread over selected areas as directed by the Engineer. Wood chips used as mulch for slope erosion control shall have a maximum thickness of 12 mm and faces not exceeding 3900 mm2 on any individual surface area. Wood chips not designated for use under other sections shall be spread over the designated areas in layers not to exceed 75 mm loose thickness. Diseased trees shall be buried or disposed off as directed by the Engineer.
All merchantable timber in the clearing area which has not been removed from the right of way prior to the beginning of construction, shall become the property of the Contractor, unless otherwise provided.
Low hanging branches and unsound or unsightly branches on trees or shrubs designated to remain shall be trimmed as directed. Branches of trees extending over the roadbed shall be trimmed to give a clear height of 6 m above the roadbed surface. All trimming shall be done by skilled workmen and in accordance with good tree surgery practices.
Timber cut inside the area staked for clearing shall be felled within the area to be cleared.
100.2.3 Individual Removal of Trees or Stumps
100.3 Method of Measurement
Measurement will be by one or more of the following alternate methods:- Area Basis. The work to be paid for shall be the number of hectares and fractions thereof acceptably cleared and grubbed within the limits indicated on the Plans or as may be adjusted in field staking by the Engineer. Areas not within the clearing and grubbing limits shown on the Plans or not staked for clearing and grubbing will not be measured for payment.
- Lump-Sum Basis. When the Bill of Quantities contains a Clearing arid Grubbing lump-sum item, no measurement of area will be made for such item.
- Individual Unit Basis (Selective Clearing). The diameter of trees will be measured at a height of 1.4 m above the ground. trees less than 150 mm in diameter will not be measured for payment.
When Bill of Quantities indicates measurement of trees by individual unit basis, the units will be designated and measured in accordance with the following schedule of sizes:
| Diameter at height of 1.4m | Pay Item Designation |
|---|---|
| Over 150 mm to 900 mm | Small |
| Over 900 mm | Large |
100.4 Basis of Payment
The accepted quantities, measured as prescribed in Section 100.3, shall be paid for at the Contract unit price for each of the Pay Items listed below that is included in the Bill of Quantities, which price and payment shall be full compensation for furnishing all labor, equipment, tools and incidentals necessary to complete the work prescribed in this Item.Payment will be made under:
| Pay Item Number | Description | Unit of Measurement |
|---|---|---|
| 100 (1) | Clearing and Grubbing | Hectare |
| 100 (2) | Clearing and Grubbing | Lump Sum |
| 100 (3) | Individual Removal of Trees, Small | Each |
| 100 (4) | Individual Removal of Trees, Large | Each |
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