The overall approach that the promoter and developer of a landfill should take is that of embarking on a construction project, carried out over an extended period, to build a desired landform using waste materials and incorporating appropriate environmental protection measures.

This concept combines the following two elements in ways which are appropriate for a particular site and its waste inputs:

1. Established civil engineering practices for permanent and temporary construction, based on a predetermined design, with appropriate performance standards for the materials used.

2. Process engineering to accommodate biological, chemical and physical changes which will take place within organic wastes during the active life of the site.

The important components to be considered and then built into all landfill designs are:

• Requirements for environmental protection, in order to minimise harm to the environment and to human health, in accordance with current legislation and the aims of sustainable development.

• Recognition of the effects of the different nature of wastes and their degradation processes on landfill gas and leachate generation, and the potential of these to change during the course of design and operation of the site.

• Use of a site-specific risk assessment, rather than prescriptive, approach to environmental protection, for each element and at each stage in the project, in order to determine the overall design and operational practices appropriate to the environmental setting of each individual landfill site.

• A holistic approach to landfill design and operation, utilising scientific and engineering skills as an integrated process from initial conception to final capping, including subsequent restoration and aftercare.

• The adoption of methods, standards and operational systems, based on best current practice, which reflect progress in techniques and improving standards.

• The underpinning of all actions by a quality approach, to ensure that the required quality is achieved in implementation, and that landfill standards match rising public expectations.

The need for cost-effectiveness in design, construction and operation of landfill sites to ensure that the appropriate level of environmental protection is achievable at an appropriate cost, is of course also essential, as is the need to comply with the local regulations imposed in respect of planning and emissions reduction and control/monitoring.

The method of landfilling is very simple. In essence the waste is deposited in layers, called lifts , within the landfill and above the liner system. As waste is deposited, it is compacted by heavy machinery to maximize the amount of refuse that can be disposed of in the landfill. Waste is not a high tech problem it is a low-tech problem.

What will make landfills better is not magic new technology, no new machines either; it is better design, better organization, better education, both at the municipality level and the site level.

Also for a good landfill both the main emissions of landfill gas and leachate should be planned for from the start, and the facilities for both installed ahead of when they are absolutely needed, to be sure they are ready when really necessary.

Leachate can be pumped to the collection pond or flow to it by gravity. A leachate collection tank is designed to catch and isolate the contaminants that can get into the environment. All good landfills attempt contain leachate at the site and prevent its discharge to surface or groundwaters, but it is easy to leave the provision of leachate treatment too late, and the not have a facility ready for when heavy rains arrive.