The development of a strategy for Biffa Waste Services to reduce its atmospheric emissions of landfill methane

The thesis considers the environmental policy statement of Biffa Waste Services to progressively reduce its methane emissions to atmosphere, and then sets out to develop a strategy for achieving this aim. As a major waste disposal company, disposing of 5.5 million tonnes of waste to landfill in 1999, the production of methane from the biodegradation of this landfilled waste is significant, and also an important proportion of UK landfill methane emissions as a whole. It was necessary to develop a sufficiently accurate method of quantitative measurement of methane production, and a computer based mathematical model was developed. It was tailored for six alternative waste streams in order to give flexibility for the changing nature of site inputs. Waste inputs for each of 40 Biffa landfills were gathered, categorised and analysed from 1983 onwards and the results totalised. This was checked against 2 alternative existing gas production models used by AEAT and the USEPA. Alternative methods of methane disposal were considered, taking into account the wide range of potential calorific values of the gas and the application to differing types of landfill. Existing and potential disposal strategies are then considered using the various gas management technologies available and the software used as a 'what if analysis tool to investigate the potential impact of various proposals. The software is equally valid for assessing the effect of future reductions in the amount of biodegradable waste that will result from the implication of the EL) landfill directive