## 10.2.3 Gates 

A sliding gate shall be installed at the entrance to the wastewater treatment plant site. 

The gate shall be operated both mechanically and manually. The gate shall be operated by a control panel button in the guard house. The height of the gate shall be 1.20 m. 

The gates shall be complete with all fittings such as rails, wheels, drop bolts; back catches, locking bars, lock plates and lock including three keys. The gates shall be provided with locks of the cylinder type. 

## 10.3 Landscaping 

## 10.3.1 General 

Prior to commencement of any landscaping work, the Contractor shall submit to the Engineer for approval his detailed proposals for landscaping including the proposed species of grass, trees and shrubs. 

## 10.3.2 Material 

## Top Soil 

Existing top soil stripped from the site and stored in heaps adjacent to the works may be reused provided it has not become contaminated and is free of rubble and debris. Where insufficient site top soil is available additional humus shall be imported from an approved source. Where the upper layer of natural soil is poor in organic matter, it shall be improved to a minimum depth of 250 mm by add- ing either clay or sand or silt to create a loamy soil texture consisting of 40% sand (size > 0.05 mm), 30% silt (size 0.05 - 0.002 mm) and 30% clay (size < 0.002 mm). 

## River Sand 

River sand for use on the site shall be obtained from an approved source. 

## Grasses 

Type of grasses shall be proposed by the Contractor and approved by the Engineer. 

Where the topsoil shall be sown with grass seed, the top 75 mm of the topsoil shall be brought to a fine tilt suitable for seeding, and sowing shall be carried out as soon as practicable after completion of top soiling having due regard to the season and the weather conditions. After the seed has been sown uniformly, they shall be raked and lightly rolled into the surface. The young grass shall be kept free from weeds and any bare patches shall be re-seeded until an even close turf is established. The grass shall be watered and rolled as required and maintained in good condition. 

## Trees and Shrubs 

Trees and shrubs shall be of the species proposed by the Contractor and approved by the Engineer and shall be of the best quality and free from disease. They shall be young stock or in the case of shrubs may be established seedlings or cuttings. All must be sufficiently mature to survive transplanting from the supply nursery. The rood systems of all plants shall be maintained intact in the soil in which they have been grown and may be supplied in containers. 

## Gravel 

Gravel for use on the site for landscaping shall comply with TSE and be of 28 mm nominal size. 

