Preparatory work

Earthworks - All onsite contractors must perform an underground services check and abide by appropriate Dial before You Dig information. 

Any damage to utility infrastructure will be the responsibility of the developer.


Machinery

Construction vehicles and equipment must be washed down and free of seed and soil before entering the site to prevent the spread of weeds, seeds and pathogens.


Environmental protection

Any works performed must be in accordance with the site management plan in regard to the protection from sediment movement off the site into waterways and storm water systems. Remnant vegetation is to remain and should be protected prior to work commencing and Council’s Environment and Natural Resources Unit advised of the protection plan.


Site litter retention and sediment control

The site management plan must include a site litter retention plan and a sediment control plan, for example: fencing downwind of the predominant wind direction, regular site clean ups, rubbish removal and disposal and sediment traps as required.

Methods available for controlling the movement of sediment on the site include:

  • Hay bale sediment fences
    The hay bales should follow the contours of the land as much as possible and be embedded into the ground, butted together as tightly as possible and secured.

  • Geotextile sediment fences
    The geotextile fabric should be secured with the bottom of the fabric buried to make it secure, and to ensure that water is not able to pass underneath the fabric untreated.

  • Grass filter strips
    Grass filters can be used on the footpath adjacent to and flush with the top of the kerb. The filter strip consists of a single roll of turf laid along the kerb with a 1.5 metre long strip laid perpendicular to the kerb every 10 metres.

The site must be progressively stabilised and rehabilitated as the project progresses to minimise the area of unstable ground. The maintenance of sediment control devices must continue until the site has been adequately stabilised and the risk of erosion is minimised.


Fill material

Wherever possible, material should be obtained from site. Should imported soil be required, written certification including source, site history and laboratory analysis confirming the soil complies with the EPA’s ‘Fill Material’ categorisation must be provided to the Council Representative. Imported fill will require a visual inspection and approval by the Council Representative prior to unloading on site. Fill shall be free of any deleterious material, including weed material or seed, vegetation, debris, building waste, asbestos and rock.

All rubbish must be removed from the site at the contractor’s/developer’s expense.

Structural fill shall be spread and compacted in accordance with the requirements of the current applicable Australian Standards.


Backfilling

Unless otherwise noted on drawings, backfilling and compacting for irrigation trenches and minor excavations may be site-won materials, provided such filling is sound material free of perishable material or any material that will not form stable fill and is to the satisfaction of Council. All vegetation, topsoil, debris, building waste, rock and rock floaters shall not, under any circumstances, be used as fill and all such materials shall be separated out from any site-won material considered suitable for filling.


Topsoil

Where possible, site topsoil should be used for garden beds and lawns. In acquiring site soil, the top 100 millimetre layer shall be stripped of vegetation and stockpiled on the site. Soil for use in garden bed and lawn areas may then be obtained from the stockpile soil provided the soil meets the requirements as stated below.


Existing soil

  • Free from perennial weeds and their roots, bulbs or rhizomes.

  • Free from building rubble, including bricks, concrete, plaster, timber, oil or any other matter deleterious to plant growth.

  • Free from rocks or stones greater than 5 millimetre diameter, but in any case, to have less than 5% stone by dry weight.

  • Texture to be light to medium friable.


Imported soil

Should imported soils be required, the subsoil shall be ripped and cultivated to a depth of 300 millimtres to combine with existing soil/base (refer to Australian Standard AS4419 “Soils for Landscaping and Garden Use”). Imported soils should be:

  • Free from perennial weeds and their roots, bulbs or rhizomes.

  • Free from building rubble, including bricks, concrete, plaster, timber, oil or any other matter deleterious to plant growth.

  • Free from rocks or stones greater than 5 millimetre diameter, but in any case, to have less than 5% stone by dry weight.

  • Ph to be 6.0 - 7.0.

  • Texture to be light to medium friable.

  • Free from silt material.

  • Non-hydrophobic.

The soil shall conform to the following sieve analysis:

Table 1: Sieve analysis

AS Sieve size (millimetres) % Passing by mass
2.35 100
1.18 90 - 100
0.600 70 - 80
0.300 45 - 55
0.150 20 - 30
0.075 5 - 15
0.002 3 - 5

Table 1: Sieve analysis

Where imported topsoil is to be used in landscape construction, three randomly selected samples shall be comprehensively laboratory tested to meet the above requirements. Copies of laboratory certificates demonstrating the mix is in accordance with the above requirements, including details of the soil source, are to be provided to Council prior to spreading imported soil on site.


Excavated rocks

Any earthworks, including the removal of excavated rocks, must be in accordance with the Environmental Management Plan for the site. Should excavated rocks need to be removed from the site, it must be ensured that the removal process will not cause major disturbance to adjacent works or the surrounding site.

Under no circumstances should rocks be moved into existing waterway reserves.

Any earthworks adjacent to a waterway must retain as much embedded and surface material as possible. Table 1: Sieve Analysis 10 City of Greater Geelong Landscape Standards Manual


Standard subsoil drainage detail

Where appropriate, provide subsoil drainage to prevent the ponding of surface water in garden beds or grassed areas adjacent to hard paving.

Figure 1: Subsoil drainage detail

Figure 1: Submsoil drainage detail with table showing 7 points: 1 - woodchip mulch; 2 - topsoil; 3 - cultivate subsoil to a minimum depth of 150mm and grade to fall; 4 - paving; 5 - existing sub-grade; 6 - 5-7mm drainage screenings (with no fines); 7 - 100mm PVC AG Drain/UPVC slotted drain pipe or on site retention system/wetland.
Click to Enlarge Image


Weed eradication

A Weed Management Plan, where applicable, shall be followed and implemented throughout the landscape works period.

The Weed Management Plan is to incorporate:

  • Location, species and extent of weed infestation;

  • Weed management prior to landscape works; and

  • Weed management at the completion of landscape works with recommended ongoing treatment methods and timeframes.

A weed eradication program shall be implemented to all areas scheduled for lawn and planting. Following topsoil placement, fine grading, and the installation of a fully functioning irrigation system (where applicable), establish a regular watering program that will encourage germination and growth of weeds over a two to three week period to remove weed seed bank from the soil.

The Contractor shall wait an additional one to three weeks, depending on extent of weed desiccation, to remove residual weed foliage and roots prior to sprigging of turf.

Please note: contact should be made with Council’s Environment Department regarding weed control.


Herbicides

Only herbicides registered for use in Victoria may be used. All herbicides and pesticides are to be used in strict accordance with the manufacturer’s instructions at the recommended rates. Herbicides may only be applied by a qualified contractor, certified specifically for herbicide applications.

Herbicides are not to be used in the vicinity of playgrounds or childcare centres. In areas of high density planting, spray hoods must be used to prevent damage to non-target species. Large weeds should be removed manually.


Noxious weeds

All declared noxious weeds should be removed or treated accordingly (reference: Conservation and Land Protection Act 1994).





Page last updated: Monday, 20 February 2017

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