Section 300 - Volume 2 Modifications

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Andhra Pradesh State Highways Project SECTION 300 - EARTHWORK, EROSION CONTROL AND DRAINAGE Clause 301 EXCAVATION FOR ROADWAY AND DRAINS Sub-Clause 301.2.1 Classification Delete paragraph (c) and replace with: “(c) Hard rock (requiring blasting) For the purposes of this contract hard rock shall describe all material, to be excavated to achieve the road design cross section including drains, which cannot be ripped and excavated with a track dozer in good condition with matching hydraulic single shank ripper of combined mass not less than 52 tonnes (this refers to a Caterpillar D9L or it’s equivalent) at a rate in excess of 90m 3 (solid) per hour. Isolated boulders greater than 1.0 cubic metres in volume may be included in this definition.” Sub-Clause 301.3.3 Excavation - General Delete the last two sentences of last paragraph. Sub-Clause 301.3.11 Disposal of excavated materials Delete this sub-clause and replace with: “All the excavated materials shall be the property of the Employer. Suitable material obtained from the excavation of the roadway, shoulders, verges, drains, cross drainage works, etc. shall be used for: i. filling for roadway embankments. Bidder Engineer in Chief (R&B) (Admin and EAP) Volume 2 Version 24-3

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Section 300 - Volume 2 Modifications

Transcript of Section 300 - Volume 2 Modifications

SECTION 300 - EARTHWORK, EROSION CONTROL AND DRAINAGE

Andhra Pradesh State Highways Project

SECTION 300 - EARTHWORK, EROSION CONTROL AND DRAINAGEClause 301

EXCAVATION FOR ROADWAY AND DRAINSSub-Clause 301.2.1ClassificationDelete paragraph (c) and replace with:

(c)Hard rock (requiring blasting)

For the purposes of this contract hard rock shall describe all material, to be excavated to achieve the road design cross section including drains, which cannot be ripped and excavated with a track dozer in good condition with matching hydraulic single shank ripper of combined mass not less than 52 tonnes (this refers to a Caterpillar D9L or its equivalent) at a rate in excess of 90m3 (solid) per hour. Isolated boulders greater than 1.0 cubic metres in volume may be included in this definition.

Sub-Clause 301.3.3 Excavation - GeneralDelete the last two sentences of last paragraph.

Sub-Clause 301.3.11Disposal of excavated materialsDelete this sub-clause and replace with:

All the excavated materials shall be the property of the Employer. Suitable material obtained from the excavation of the roadway, shoulders, verges, drains, cross drainage works, etc. shall be used for:

i.filling for roadway embankments.

ii.filling existing pits in the right of way as directed by the Engineer, including levelling and spreading, with all lifts and lead up to 2000m.

iii.for landscaping of the road as directed by the Engineer, including levelling and spreading, with all lifts and lead up to 2000m.

Unsuitable and surplus material, which, in the opinion of the Engineer cannot be used in the Works, shall be removed from site by the Contractor and disposed of at the nearest tip or other approved location in accordance with all statutory requirements.

Sub-Clause 301.3.12BackfillingAfter the last sentence add the following:

Density requirements for backfilling shall be in accordance with Table 300-2."

Sub-Clause 301.6Preparation of Cut FormationAt the end of the second last paragraph add the following:

A geotextile will be placed at the base of the excavation where directed by the Engineer. The geotextile shall be approved by the Engineer and shall comply with the requirements of Sub-Clause 706.

Sub-Clause 301.8Measurements for PaymentDelete the second and third sentences of the third paragraph and replace with:

Excavation in soil and ordinary rock shall be paid under the same item in all cases except the excavation of bridge foundations.

Delete items (iv) & (v) and replace with:

iv.Stripping including storing or disposal of top soil.....................cu.m.

v.Reapplication of top soil............................................................cu.m.

vi.Haulage of suitable material beyond initial 2000m lead............cu.m..

vii.Geotextile...................................................................................sq.m.

Items iv and v above shall also include topsoil quantities relating to embankments. Refer to Clause 305.

Sub-Clause 301.9RatesSub-Clause 301.9.1

In item (ii) replace 1000m with 2000m.

Add extra item after item (vi):

(vii)The removal from site and disposal of all surplus or unsuitable materials obtained from excavation operations, which, in the opinion of the Engineer cannot be used in the Works, shall be included in the Contract rate.

Sub-Clause 301.9.2This Sub-Clause shall read as :

The Contract unit rate for loosening and re-compacting at subgrade level shall include full compensation for loosening to the specified depth, removing the loosened soil outside the roadway excavation, rolling the surface below, breaking the clods, spreading the excavated soil in layers, watering where necessary and compacting to the requirements.

Sub-Clause 301.9.5Replace 1000m with 2000m in the first sentence.

Sub-Clause 301.9.6

Replace 1000m with 2000m in the first sentence.

Sub-Clause 301.9.7Payment for geotextileAdd new Sub-Clause.

The unit rate for placing geotextile after removal of unsuitable material shall include, cutting and lapping and all labour, materials, tools, equipment and incidental required to compete the work in accordance with Sub-Clause 706.

Clause 304

EXCAVATION FOR STRUCTURESSub-Clause 304.3.4 Preparation of FoundationIn Paragraph 2 and 3 of Sub-Clause 304.3.3, substitute concrete M10" in place of 1.3.6 nominal mix.

Sub-Clause 304.4Measurement for PaymentAfter the second sentence of the first paragraph add:

Excavation in soil shall be measured relative to the depth below existing surface level as follows:

(i)up to 3m

m3(ii)3m to 6m

m3(iii)more than 6m

m3Sub-Clause 304.5.1Delete item (v) and replace with:

(v)backfilling, clearing up the site and disposal of all surplus or unsuitable material, which, in the opinion of the Engineer cannot be used in the Works, at the nearest tip or other approved location in accordance with all statutory requirements.

Sub-Clause 304.5.3

Delete this sub-clause.

Clause 305 EMBANKMENT CONSTRUCTIONSub-Clause 305.2.1.1Delete the subsection (e) in the second paragraph and replace with the following:

(e) Soils having a liquid limit exceeding 35 and a plasticity index exceeding 18; and

Sub-Clause 305.2.1.2

This Sub-Clause shall read as under:

Highly expansive soils such as CH, MH or OH exhibiting marked swell and shrinkage properties (free swelling index exceeding 50 per cent when tested as per IS: 2720-Part 40) shall not be used in construction of subgrade and embankment.

Sub-Clause 305.2.1.4

Delete second sentence of Sub-Clause 305.2.1.4

Sub-Clause 305.2.1.6

Add new Sub-Clause.

Material used as subgrade in embankments (depth of 500mm immediately below the pavement) shall have a 4 day soaked CBR value at least equivalent to the CBR assumed in the design and shown on the drawings.

Sub-Clause 305.2.1.7

Add new Sub-Clause:

Geotextile placed at the direction of the Engineer after removal of unsuitable material shall be approved by the Engineer and shall comply with the requirements of Sub-Clause 706.

Sub-Clause 305.2.2.2 Borrow materialsDelete paragraphs 1 and 2 and replace with the following:

Borrow areas have not been designated by the Employer. The arrangement for locating the source of supply of the material for embankment as well as compliance to the different environmental requirements in respect of excavation and borrow areas as stipulated, from time to time, by the Ministry of Environment and Forest, Government of India and the local bodies, as applicable shall be the sole responsibility of the Contractor.

Borrow pits along the road shall not be permitted within the right of way or immediately adjacent to the right of way.

Paragraph 8 of this Sub-Clause given below Table 300-2 shall read as under:

The Contractor shall, at least 7 working days before commencement of compaction, submit the following to the Engineer for approval.

(i)The values of maximum dry density and optimum moisture content obtained in accordance with IS: 2720 (Part 8) for each fill material intended for use.

(ii)The graphs showing values of density against moisture content from which the maximum dry density and optimum moisture content in (i) above were determined.

(iii)The dry density-moisture content - CBR relationships for each of the fill materials intended for use in the subgrade. The adopted CBR value shall be the 4 day soaked CBR value determined in accordance with IS:2720 (Part 16).

Where material suitable for use as subgrade is available within 2 km of the work site, the Contractor shall not source the subgrade material from borrow areas.

Sub-Clause 305.3Construction OperationsSub-Clause 305.3.4 Compacting ground supporting embankment/subgradeAfter the third paragraph add the following:

A geotextile shall be placed at the base of the excavation after removal of unsuitable material if so directed by the Engineer.

Sub-Clause 305.3.5 Spreading material in layers and bringing to appropriate moisture contentSub-Clause 305.3.5.2

In para 3, substitute IS:2720 (Part 8) for IS:2720 (Part 7) or IS:2720 (Part 8) as the case may be.

Sub-Clause 305.3.9Finishing OperationsAdd after the fourth paragraph:

Work shall be completed within the following time frames:

i.Vegetation of Areas with Slopes 3 to 1 or Flatter:

Where earthworks requiring revegetation have been completed over an area exceeding one hectare, vegetation shall be carried out within fourteen days.

ii.Vegetation of Areas with Slopes Steeper than 3 to 1:

Where earthworks requiring revegetation have been completed over an area exceeding one hectare, vegetation shall be carried out within seven days.

iii.Open drains shall be vegetated within seven days of excavation.

Sub-Clause 305.4.3Earthwork over existing road surfaceReplace item (i) with:

If the existing road surface is of a bituminous type and lies more than 500mm below formation level, the same shall be scarified to a depth of 50mmbelow the underside of the bitumen, or more if specified, so as to provide an ample bond between the old and the new material. Where the existing road surface is less than 500mm below formation level, the existing surface shall be prepared for overlay in accordance with Clause 401.4.1

Delete item (iii)

Sub-Clause 305.4.7Earthwork for high embankmentDelete the first paragraph and replace with:

Material used in high embankments, including subgrade material constituting the 500 mm of embankment immediately below the pavement, shall have a minimum effective angle of internal friction () of not less than 200 and minimum effective soil cohesion (c) of not less than 1.0 t/m2. High embankment shall be constructed from borrow material in accordance with Sub-Clause 305.2.2.2 unless otherwise approved by the Engineer.

Sub-Clause 305.8Measurements for PaymentDelete the fifth paragraph and replace with:

Stripping including storing and reapplication of topsoil for embankments shall be measured in cubic metres. Payment shall be made under the relevant items of Sub-Clause 301.8

Delete the last sentence and replace with:

Filter medium behind abutments, wingwalls and other retaining structures and compacted sand backfill to foundations shall be measured as finished work in position in cubic metres.

Geotextile placed after removal of unsuitable material shall be measured in square metres of geotextile placed.

Sub-Clause 305.9.1

Add the following at the end:

Except where filter medium or compacted sand backfill to foundations is specified on the drawings or by the Engineer, no additional payment shall be made for backfill to abutments, wingwalls and other retaining structures. Backfill to retaining structures shall be measured as normal embankment.

Sub-Clause 305.9.2

Delete this Sub-Clause and replace with:

The unit rate for embankment from borrow shall include the costs of all leads from borrow areas.

The unit rates for subgrade, and high embankment shall include the costs of all leads from borrow areas where these items are constructed from borrow material.

Sub-Clause 305.9.3Delete this Sub-Clause

Sub-Clause 305.9.8Delete this Sub-Clause and replace with:

The Contract unit rate for providing and laying filter material behind abutments and compacted sand backfill to foundations shall be payment in full for carrying out the required operations including all materials, labour, tools, equipment and incidentals to complete the work to Specification.

Sub-Clause 305.9.11Add new Sub-Clause:

The unit rate for placing geotextile after removal of unsuitable material shall include, cutting and lapping and all labour, materials, tools, equipment and incidental required to compete the work in accordance with Sub-Clause 706.

Clause 306

SOIL EROSION AND SEDIMENTATION CONTROLSub-Clause 306.4Measurements for PaymentDelete this Sub-Clause and replace with the following:

All temporary sedimentation and pollution control works shall be deemed as incidental to the earthworks and other items of work and no separate payment shall be made for these items.

Sub-Clause 306.5RatesDelete this Sub-Clause.

Clause 308

SEEDING AND MULCHING

Sub-Clause 308.2MaterialsA.Seeds

Delete the first and second sentences and replace with:

The seeds shall be of approved quality and of the type shown on the drawings and shall have acceptable parity and germination to requirements set down by the Engineer.

The Contractors attention is drawn to the lead time that may be required to procure some native seed species. The Contractor shall submit to the Engineer the name(s) of the proposed seed supplier(s) within two weeks of the acceptance of the tender.

The native seed shall be delivered to the site in separate lots for each species and variety, clearly labelled to show species, variety and weight. Grass seed shall be pre-packed commercially with an accompanying certificate of germination. The Contractor shall advise the Engineer of the unavailability of any of the specified seed species at least six weeks in advance of sowing.

The Contractor shall notify the Engineer in writing at least five days prior to commencing vegetation of an area. Fertiliser used shall be an organic type having an N:P:K analysis (stated in elemental form) within the following range:

N:5.0% to 9.0%

P:1.0% to 4.0%

K:2.0% to 4.0%

Fertilizer shall be delivered to the site in unopened standard bags or containers bearing the manufacturers description, analysis of constituents and quantity. The Contractor shall advise the Engineer at least two days before applying fertiliser to allow the Engineer to inspect the unopened bags or containers. Straw to be used in mulching operations shall be derived from cereal crops comprising wheat, oats or rice. Meadow hay or weeds shall not be used. Water used shall be potable.

B.Top soil

After the third sentence add:

The Contractor shall use topsoil stockpiled on site from material previously identified by the Engineer for stripping and re-use as topsoil. Before use for vegetation work topsoil shall be screened or sorted to remove stumps, roots, stones greater than 50mm in size.

C.Bituminous Emulsion

Delete the first sentence and replace with:

The binder used in straw mulching shall be the a slow setting anionic bitumen emulsion.

Sub-Clause 308.3.1Seed-bed preparationReplace 150mm with 100mm

Replace 100mm with 150mm

Add after the first paragraph:

Where shown on the Drawings areas of old road formation shall be ripped through the full thickness of the pavement. Areas outside the earthworks directed by the Engineer to be seeded with native mix shall also be prepared in accordance with this Sub-Clause.

Sub-Clause 308.3.2Fertilizer ApplicationAdd after the first sentence:

Fertilizer shall be applied only to areas to be seeded with native seed. Fertilizer shall not be applied to areas to be seeded with native grass. Where specified, fertilizer shall be applied at a rate of 1000 kg per hectare.

Sub-Clause 308.3.3Planting of seedsAdd after the first paragraph:

The Contractor shall maintain records of measurements and calculations to determine actual distribution rates for each lot.

Add after the second paragraph:

Seeding should not be carried out in unfavourable weather conditions when the wind exceeds 15 km/hr or during rain periods. Native seeding should take place just prior to the onset of the wet season.

Sub-Clause 308.3.4Soil moisture and watering requirementsDelete this Sub-Clause and replace with:

If necessary, the Contractor shall water areas to be seeded such that soil moisture shall exist throughout the zone from 25mm to at least 125mm below the surface at the time of planting.

Sub-Clause 308.5MaintenanceAdd after the first paragraph:

Watering is to be carried out over the whole of the area to be seeded over a 12 month period such that strong growth is achieved, but shall not be less frequent than:

every three weeks between the beginning of February to mid April

every ten days from mid April until mid June, and

every month thereafter except that watering is not required during the wet season (commencement and completion of the wet season to be determined by the Engineer).

Watering shall be carried out such that soil moisture shall exist to a depth of 125mm below the surface.

Watering shall be carried out early in the morning and as late in the evening as possible.

Seed areas which do not exhibit strong growth shall be reseeded as directed by the Engineer.

During the maintenance period the Contractor shall be responsible for keeping seeded areas secure from damage by animals or other sources.

Sub-Clause 308.7RateAdd after the first paragraph:

The rate for seeding and mulching shall include fertilizer where specified, mulching material including organic manure, bituminous emulsion, watering and maintenance. Payment for native grass and native seeding shall be made as follows:

50% of payment due for the relevant items after completion of seeding and mulching to the satisfaction of the Engineer.

remaining 50% to be paid 12 months after seeding. This part of the payment is to be made in proportion to the area over which a strong grass cover as determined by the Engineer, has been established.

Sub-Clause 308.8Other areas disturbed by the ContractorAdd new Sub-Clause:

Other areas disturbed by the Contractors construction activities (such as areas for compounds, material storage, access and haul roads) shall be restored by vegetation in accordance with Section 308. This work shall be at the Contractors cost.

Clause 309

SURFACE/SUB-SURFACE DRAINS

Sub-Clause 309.2Surface DrainsAdd at the end of the third paragraph:

The concrete lining of the concrete lined drains shown on the drawings shall be constructed in accordance with the requirements of Clause 408.

Metal grates for sumps on concrete lined surface drains shall be heavy duty (trafficable by commercial vehicles) proprietary products with gaps between bars no greater than 25mm. The Contractor shall submit proposals for grating to the Engineer for approval before commencing construction of the sumps.

Add at the end of the fourth paragraph:

Surface drains shall be constructed as soon as possible after or during construction of the embankment and prior to construction of the Base.

Sub-Clause 309.3.1Scope

Delete the last sentence in the first paragraph and replace with:

Subsoil/subsurface drains shall be placed in a trench lined with geotextile. The geotextile shall be approved by the Engineer and shall comply with the requirements of Sub-Clause 702. Granular filter material for subsoil drains shall meet the grading requirements of Class II material as shown in Table 300-3.

Sub-Clause 309.4Measurements for PaymentDelete this Sub-Clause and replace with:

Surface drains not lined with concrete running adjacent to the road formation (side drains) shall be included in the items for excavation for the roadway in accordance with Sub-Clause 301.8. Surface drains that are not adjacent to the roadway and that therefore cannot be constructed as part of the roadway excavation shall be measured in cubic metres of excavation. Measurement for sub-surface drains shall be per running metre length of drain. Concrete lined surface drains shall be measured per running metre length of drain.

Measurement of inlet sumps and metal grates associated with surface drains shall be by number.

Sub-Clause 309.5RatesIn the first sentence delete except for removal of unsuitable material for which the lead shall be 1000m and replace with including removal from site and disposal of all surplus or unsuitable materials, which, in the opinion of the Engineer cannot be used in the Works.

In the second sentence delete gratings, sumps,.

Delete the third sentence and replace with:

The rate for subsoil drain shall also include geotextile, granular backfill, perforated pipe, connection to pipes or sumps and construction of outlets as detailed. The rate for concrete lined drain shall also include bedding concrete and jointing.

Clause 310

PREPARATION AND SURFACE TREATMENT OF FORMATIONDelete item (b) and replace with:

The surface shall be rolled to achieve the required compaction in accordance with Table 300-2.

Add new Clause:

Clause 314

TREE PLANTINGSub-Clause 314.1ScopeThis Sub-Clause covers the planting (including mulching and fertilising), watering and maintenance of trees as shown on the Drawings, listed in the Specification, or as directed by the Engineer.

Sub-Clause 314.2TimingUnless otherwise directed by the Superintendent, planting shall be carried out within seven (7) days of seeding operations, to avoid unnecessary disturbance of areas of existing vegetation and of areas of the works previously topsoiled and seeded, or straw mulched.

Sub-Clause 314.3ProceduresAll work specified shall be carried out under the supervision of an experienced landscape tradesman satisfactory to the Engineer.

Planting work includes:

(a) Planting of tree species on roadside margins as shown on the Drawings, or as directed by the Engineer. All planting copses are to be kept clear of all drainage lines, overhead wires and all other public utilities.

(b) Allowance shall be made in the rates quoted for the supply of any water or watering facilities necessary for the planting and maintenance of the trees. Water shall be free from oils, salts, acids, alkalis, organic matter and any other matter which would affect the growth of plants. Plant root systems shall be maintained moist at all times with particular attention prior to and immediately after planting.

(c) Preservation of Existing Vegetation

Existing vegetation shall be preserved and protected except where otherwise specified or directed. Protective measures for existing vegetation shall include :

(i)Machinery movement over and disturbance to surfaces adjacent to existing trees shall be kept to a minimum.

(ii)Deleterious material including oil, petrol, cement, bitumen, spillage from washing operations and similar contaminants shall be kept clear of trees, shrubs and grass including their root systems.

(iii)Materials shall not be stockpiled over root systems.

(iv)Damage to overhead tree canopies by machine or truck operations shall be avoided.

(d)Method of Work

The Contractor shall organise his planting work and methods so as to minimise damage to surface vegetative work already done under this Contract, by topsoiling and seeding, or by other methods. Damage to the existing vegetation caused by the Contractors tree planting operation shall be rectified at the Contractors expense.

(e) Transportation and Storage of Plants

The loading, transporting and unloading of plants from holding areas to planting sites shall be undertaken in a manner that causes minimal disturbance to the rootball, and the overall stability of the plants. The Contractor shall ensure that all care is taken in the transportation of plants to and from the work site. Plants deemed by the Superintendent to have been damaged by the Contractor, through the Contractors neglect and/or mishandling, shall be rejected and replaced at the Contractors expense. The storage of plants shall be at a site approved by the Engineer. It shall be located in an area protected from wind, dust, vermin and be accessible to an adequate water supply. During transportation and storage, plant containers shall be kept moist at all times. Plants deemed by the Superintendent be suffering from stress, due to the Contractors neglect in providing adequate water or for any other reason, shall be rejected and replaced by the Contractor at his expense.

(f)Setting Out

The positions of all plantings shall be set out in accordance with the Drawings, or as directed by the Engineer. An inspection shall be undertaken by the Engineer prior to the commencement of planting operations.

Sub-Clause 314.4Materials for LandscapingSub-Clause 314.4.1TopsoilThe quality and source of topsoil to be used shall be as specified in Section 308. In addition, planting holes shall be filled with topsoil with a pH adjusted to 5.5 if it is below 4.5.

Sub-Clause 314.4.2FertilizerFertilizer shall be a slow-release type in pellet form with an 8-9 months release period and an N.P.K ratio approximately equal to 20-4-8. Fertiliser shall be delivered to the site not less than two weeks prior to use in unopened standard bags or containers bearing the manufacturers description, analysis of constituents and quantity. The Contractor shall test the fertiliser for conformance of constituent elements prior to using the fertiliser in the work.

Sub-Clause 314.4.3MulchOnly that material that is free of soil, weeds, stones, vermin, insects or other foreign material shall be used as mulch. Mulch used in landscape planting shall be one of the following or a suitable alternative approved by the Engineer.

(i)A layer of stone 100mm thick.

(ii)Organic waste such as vegetable matter in a layer 75mm thick.

(iii)A layer of newspaper 75mm thick.

The mulch shall be free of soil, weeds, stones, vermin, insects nor other foreign material. The Contractor shall submit proposals for mulch to the Engineer for approval, 21 days before planting.

Sub-Clause 314.4.4Plant MaterialThe plants are to be supplied by the Contractor. All plants are to be supplied in the containers as specified below and shall have grown to the approved heights as specified below :

CONTAINER SIZE

APPROVED PLANT HEIGHT

Super Advanced

45 Litres

1.5m Trunk Height

Sub-Clause 314.5Planting Operations

Sub-Clause 314.5.1GeneralUnless otherwise directed by the Engineer planting shall not be carried out into dry soil in extreme summer weather conditions. Planting shall take place prior to the onset of the wet season. Plant root systems shall be maintained moist at all times with particular attention paid during the on-site period prior to and during planting.

Sub-Clause 314.5.2Individually Mulched Planting Super Advanced Size StockPlanting shall be in accordance with the landscape procedures as detailed on the Drawings and the following requirements. Planting shall be at locations indicated on the Drawings and as directed by the Engineer. The Contractor shall mark proposed planting locations for the approval of the Engineer, a minimum of 7 days before planting is to commence.

In areas where close spaced planting is to take place a Glyphosate-based herbicide approved by the Engineer shall be applied at the rate recommended by the manufacturer over the grass and weed within the area. A minimum of two applications at fourteen day intervals shall be required. No sooner than fourteen (14) days after the second application of the herbicide, the area for planting shall be evenly machine ripped and broken up to a depth of 400mm by tynes set at 300mm centres with a minimum of two passes. Each subsequent pass shall be in the opposite direction to the preceding pass.

Planting holes shall be excavated to the dimensions as shown on the Drawings. The use of an auger or similar implement to excavate planting holes is not acceptable. During planting and backfilling with site topsoil, Super Advanced sized plants shall have ten (10) fertilizer pellets placed beside the root ball. The backfilling of each hole shall then be completed and lightly compacted by tamping down so that on completion the backfilled area is flush with the natural surface level of the soil.

Immediately after back filling, mulch shall be spread to a depth as required by the Drawings and this specification. The mulch material is not to be mixed with the underlying soil during excavation and backfilling. Mulch material shall be kept just clear of the stems of plants. Trees shall be protected by steel cages in accordance with the detail on the Drawings and this Specification. Super-Advanced size plant shall receive 50 litres of water per plant, in a manner which causes minimum disturbance to the mulch, immediately after the planting operation is complete.

Sub-Clause 314.6MaintenanceThe Contractor shall water, control weeds, control insects and disease, apply fertilizer and generally maintain the works in good condition regardless of weather conditions in accordance with Clauses in this specification.

(a)Maintenance Period

The maintenance period for planting shall end at the completion of the defects liability period for the relevant road section or 12 months from the completion of planting, whichever occurs later. The Contractor shall be responsible for all maintenance requirements from the time of seeding and planting to the end of the maintenance period.

During this period the Contractor shall make good all defects and leave the site in a clean and tidy condition to the satisfaction of the Engineer. During the maintenance period the Contractor shall be responsible for keeping all plants and materials secure from damage by animals or theft.

(b)Maintenance Inspections

Routine maintenance shall be carried out at minimum monthly intervals in accordance with site requirements and prevailing weather conditions. In addition to routine maintenance visits, the Contractor shall visit the site during periods of adverse climatic conditions or as directed by the Engineer to determine status and effectiveness of maintenance previously carried out and in progress and the need for future maintenance activities.

(c)Records

The Contractor shall submit a written report to the Superintendent within four (4) days of each maintenance inspection. The report shall include date of visit, maintenance works completed, maintenance works in progress and maintenance works required. The report shall also give details of damaged or missing plants together with a location diagram. Observations and/or recommendations for additional work considered necessary for ongoing maintenance shall also be included in the report. Maintenance work required shall be approved by the Engineer or his representative before work can commence and with exception to those specifically required in the Contract.

(d)Watering

From commencement of the maintenance period plants shall be watered by minimum monthly applications. Each watering shall comprise the application of twenty (20) litres of water per plant to ensure that a distinct level of moisture is maintained. The frequency of watering the works may be reduced during periods of adequate rainfall or increased during dry periods and in accordance with the Engineers direction.

(e)Mulch

The Contractor shall maintain mulch areas in a weed free condition and where deemed necessary, at the absolute discretion of the Engineer, reinstate the mulch until completion of the maintenance period.

(f)Disease and Insect Control

During the maintenance period, plants shall be sprayed to control disease and insect infestation. The Contractor shall obtain the Engineers written approval to the type of chemical proposed for spraying before spraying is carried out. Spraying shall only be carried out in accordance with the manufacturers recommendations and only on windless days. The Superintendent shall be advised 24 hours prior to an intended spraying operation. Additional spraying may be directed by the Engineer as required. In no circumstances are pesticides to be used without the written consent of the Engineer. Where required to be used, pesticides and their application shall comply with requirements of the relevant laws and regulations.

(g)Plant Replacement

Missing or dead plants, plants in poor condition or plants nominated by the Engineer as unsatisfactory shall be removed and replaced by the Contractor, at his own cost, within 14 days of notification by the Engineer. Plant Material shall conform to Sub-Clause 314.4. Replacement plants shall be of similar size and quality and of identical species and variety to the plant being replaced unless otherwise directed by the Engineer. Replacement plants shall be planted and watered in accordance with requirements in this Specification.

Sub-Clause 314.7Measurements and PaymentThe unit of measurement for tree planting shall be per each plant. The unit of measurement for protection of trees (steel cages) shall be per each plant protected in accordance with the details on the drawings.

Sub-Clause 314.8RatesThe rate for the planting is to include supply from storage site, site preparation, excavation (in all types of material), backfilling, mulching, fertilizing, watering and maintenance of trees of the specified size.

Payment of 25% of the scheduled rate will be paid at the satisfactory completion of planting. A second payment of 25% will be paid at 3 months for those trees which are in a healthy state after

this period. For trees which have been replaced, the second payment will only be made 3 months after the trees are replanted. The final payment of 50% will be made at the end of the maintenance period for those trees which are healthy at that time. Final payment will be made for trees planted less than 6 months before the end of the maintenance period, at the discretion of the Engineer.

Payment for tree protection shall be payment in full for carrying out all operations including fill compensation for all materials labour, equipment and incidentals required to complete the works in accordance with the specifications and drawings.

Payment for tree protection works will be made in the same proportions and at the same times as the payment for planting of super advanced trees. The final payment for tree protection will only be made for trees which are healthy at the end of the maintenance period. Final payment for protection of trees planted less than 6 months before the end of the maintenance period will be made at the discretion of the Engineer.

BidderEngineer in Chief (R&B) (Admin and EAP)

Volume 2Version 24-3