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achinery in the construction process, transportation of materials and from the production of construction materials. This type of waste is emitted to the air and has inherent effects on air quality. Solid waste can be generated from demolition and excavation or may be unused material from the construction process. Some solid waste may be recycled or reused however the majority is put into landfill sites, because of this the overarching target of the UK government's strategy for sustainable construction is to reduce the amount of construction waste to landfill by 50% by 20121. Solid waste therefore adopts the associated effects on the environment that landfill has.

Of the solid waste that is put into landfill the majority comes from the demolition of existing structures and the excavation of material to allow construction, however a relatively small proportion consists of unused materials generated from amongst others, design change, lack of skilled workforce, site untidiness, poor quality materials and manufacture and lack of product information and knowledge. Unused materials will not only contribute to the environmental effects of landfill but will have indirect environmental effects due to transportation, production and packaging. The main environmental effects of waste due to demolition and excavation are emissions from transportation and primarily issues with landfill.

Landfills are widely considered to have adverse effects on the surrounding environment and public health. The main types of environmental impacts caused by landfill sites are alteration to surrounding landscape, visual intrusion, degradation of air quality, pollution of ground water and degradation of soil quality. The construction industry makes a considerable contribution as it makes up a large proportion of the total waste assigned to landfill in the UK.

Landfill sites generally occupy a large area required for waste disposal itself as well as associated facilities and enough area to minimise the effects on surrounding groundwater and soil quality. Additionally in some cases excavation and movement of material is required to create an area which is suitable for the disposal of waste. Thus, the surrounding landscape is adversely affected. The location of a landfill site is often sensibly chosen so to minimise the effects it has on the surrounding environment, however it may be impossible to locate it so that it is entirely invisible to the public and the negative visual impact a landfill site will have on a community cannot be avoided. Gaseous emissions from a landfill site come from the transportation of waste, use of machinery and more importantly the anaerobic digestion of organic matter producing methane. Generation of gas in a landfill site is one of the largest sources of methane emissions to the atmosphere; methane having a much greater global warming effect than carbon dioxide as well as being harmful to humans. Landfill sites therefore have a negative effect on air quality and public health. The precipitation that falls on a landfill coupled with the disposal of liquid wastes results in the extraction of water soluble compounds and particulate material, such as cement, dust and asbestos. Although nowadays measures are generally taken to water-proof a landfill site resulting solutions and mixtures will almost certainly end up in surrounding groundwater and soil. Thus, a degradation of groundwater and soil quality o