No abstract

To reduce emissions of greenhouse gas (GHG) from landfills, the European Union (EU) Landfill Directive 1999/31/EC requires that there be a progressive decrease in the municipal biodegradable waste disposal. The main problem of waste management (WM) in Latvia is its heavy dependence on the waste disposal at landfills. The poorly developed system for the sorted municipal waste collection and the promotion of landfilling as a major treatment option led to the disposal of 84% of the total collected municipal waste in 2012, with a high biodegradable fraction. In Latvia, the volume of emissions due to activities of the WM branch was 5.23% (632.6 CO 2 eq.) of the total GHG emissions produced in the National economy in 2010 (12 097 Gg CO 2 eq., except the land use, land-use change and forestry). Having revised the current situation in the management of biodegradable waste in Latvia, the authors propose improvements in this area. In the work, analysis of environmental impact was carried out using Waste Management Planning System (WAMPS) software in the WM modelling scenarios. The software computes the emissions, energy and turnover of waste streams for the processes within the WM system such as waste collection and transportation, composting, anaerobic digestion, and the final disposal (landfilling or incineration). The results of WAMPS modelling are presented in four categories associated with the environmental impact: acidification, global warming, eutrophication and photo-oxidant formation, each characterised by a particular emission. These categories cover an integrated WM system, starting with the point when products turn to waste which is then thrown into the bin for waste at its generation source, and ending with the point where the waste transforms either into useful material (recycled material, biogas or compost) or contributes to emissions into environment after the final disposal at a landfill or an incineration plant.

In the work, the life-cycle assessment approach is applied to the planning of waste management development in a seaside region (Piejūra) using the Waste Management Planning System (WAMPS) program. In Latvia, the measures to be taken for the climate change mitigation are of utmost importance - especially as related to the WM performance, since a disposal of biodegradable waste presents the primary source of GHG emissions. To reduce the amount of such waste is therefore one of the most significant goals in the State WM plan for 2013-2020, whose adoption is the greatest challenge for municipalities. The authors analyse seven models which involve widely employed biomass processing methods, are based on experimental data and intended for minimising the direct disposal of organic mass at the solid waste landfills. The numerical results obtained evidence that the thermal or biotechnological treatment of organic waste substantially reduces the negative environmental impact of WM practices - by up to 6% as compared with the currently existing.

The mathematical methods of waste management assessment and software for various life cycle applications are widely used as one of the decision-making support tools in waste policy. This comparatively new approach to waste management planning offers an option for investigating the life cycle impact of solid waste management processes which generate anthropogenic impact on the environment, of which the most unfavorable is greenhouse gas emission. In the research a software application called WAMPS (waste management planning system) developed by the IVL Swedish Environmental Research Institute within the Reco Baltic 21 Tech project has been used to create a better understanding about waste management processes and their produced impact on climate change. It is the first time when WAMPS software is applied for regional domestic waste management planning for the next seven-year period in the Baltic states, in this particular case for the Piejura region, which is one of the ten waste management planning regions in Latvia. The Piejura region includes one city of national level and nine districts, with the total area of about 5,300 sq. km and the number of inhabitants 153,899. In accordance with national legislation, responsibility for waste management organization has been delegated to local municipalities. In this study the solutions for elaboration of the Piejura region waste management strategy are based on those waste management processes which will produce the best environmental options. The main results of the research were obtained comparing various waste management scenarios in WAMPS: the existent situation in regional waste management, where more than 94% of domestic waste is landfilled; European Union framework demands according to Waste and Landfill directives; and the best technological solutions for the Piejura region based on local circumstances. The next phase of research will draw attention to the implementation and integration of the chosen technological solutions on the basis of economical solutions.

This paper is based on an empirical work done by author on a series of case studies such us document studies and analyzing the best practices examples. The objective of this research is to find out barriers to reach regional waste management plan demands in three municipalities: Salacgriva, Saulkrasti and Ikskile. Author gives proposal with some recommendations for development of municipal waste management as well. There are several views and attitudes of local stakeholders such us municipality, waste producers, waste collectors and mediators on how to manage collection and transportation of solid waste in practice as well as on public involvement in the process.. Passivity of stakeholders to realize theirs needs and requirements mainly depend on the limited human and financial resources, but often political will, skepticism or lack of knowledge. A lot of problems could be solved faster and easier, if there existed better communication and collaboration among local stakeholders.