Management of landfill leachate: The legacy of European Union Directives.

Landfill leachate is the product of water that has percolated through waste deposits and contains various pollutants, which necessitate effective treatment before it can be released into the environment. In the last 30years, there have been significant changes in landfill management practices in response to European Union (EU) Directives, which have led to changes in leachate composition, volumes produced and treatability. In this study, historic landfill data, combined with leachate characterisation data, were used to determine the impacts of EU Directives on landfill leachate management, composition and treatability. Inhibitory compounds including ammonium (NH4-N), cyanide, chromium, nickel and zinc, were present in young leachate at levels that may inhibit ammonium oxidising bacteria, while arsenic, copper and silver were present in young and intermediate age leachate at concentrations above inhibitory thresholds. In addition, the results of this study show that while young landfills produce less than 50% of total leachate by volume in the Republic of Ireland, they account for 70% of total annual leachate chemical oxygen demand (COD) load and approximately 80% of total 5-day biochemical oxygen demand (BOD5) and NH4-N loads. These results show that there has been a decrease in the volume of leachate produced per tonne of waste landfilled since enactment of the Landfill Directive, with a trend towards increased leachate strength (particularly COD and BOD5) during the initial five years of landfill operation. These changes may be attributed to changes in landfill management practices following the implementation of the Landfill Directive. However, this study did not demonstrate the impact of decreasing inputs of biodegradable municipal waste on leachate composition. Increasingly stringent wastewater treatment plant (WWTP) emission limit values represent a significant threat to the sustainability of co-treatment of leachate with municipal wastewater. In addition, the seasonal variation in leachate production poses a risk to effective co-treatment in municipal WWTPs, as periods of high leachate production coincide with periods of maximum hydraulic loading in WWTPs.

[1]  M. Sartaj,et al.  Treatment of municipal landfill leachate using a combined anaerobic digester and activated sludge system. , 2010, Waste management.

[2]  M. Sillanpää,et al.  Biological processes for treatment of landfill leachate. , 2010, Journal of environmental monitoring : JEM.

[3]  Kazuo Yamamoto,et al.  Influence of operating pH on biodegradation performance and fouling propensity in membrane bioreactors for landfill leachate treatment , 2015 .

[4]  Rainer Stegmann,et al.  Sardinia 99, Seventh International Waste Management and Landfill Symposium, 4-8 October, S. Margherita di Pula, Cagliari, Sardinia, Italy. Proceedings, Vol. I-V , 1999 .

[5]  G. Zeng,et al.  Landfill leachate pretreatment by coagulation–flocculation process using iron-based coagulants: Optimization by response surface methodology , 2012 .

[6]  Yu Wang.  Leachate management in the aftercare period of municipal waste landfills , 2013 .

[7]  Nadjib Drouiche,et al.  Combination of advanced oxidation and biological processes for the landfill leachate treatment , 2014 .

[8]  Mogens Henze,et al.  Wastewater Treatment: Biological and Chemical Processes , 1995 .

[9]  J. Kalka.  Landfill Leachate Toxicity Removal in Combined Treatment with Municipal Wastewater , 2012, TheScientificWorldJournal.

[10]  P Moulin,et al.  Landfill leachate treatment: Review and opportunity. , 2008, Journal of hazardous materials.

[11]  D. Frascari,et al.  Long-term characterization, lagoon treatment and migration potential of landfill leachate: a case study in an active Italian landfill. , 2004, Chemosphere.

[12]  Qingrui Zhang,et al.  Removal of ammonia from landfill leachate by struvite precipitation with the use of low-cost phosphate and magnesium sources. , 2014, Journal of environmental management.

[13]  Marc Landy,et al.  The Environmental Protection Agency , 1990 .

[14]  Osman Nuri Ağdağ,et al.  Anaerobic/aerobic treatment of municipal landfill leachate in sequential two-stage up-flow anaerobic sludge blanket reactor (UASB)/completely stirred tank reactor (CSTR) systems , 2005 .

[15]  U. Tezel.  Fate and effect of quaternary ammonium compounds in biological systems , 2009 .

[16]  A. Ledin,et al.  Present and Long-Term Composition of MSW Landfill Leachate: A Review , 2002 .

[17]  J R Gronow,et al.  Household hazardous waste in municipal landfills: contaminants in leachate. , 2005, The Science of the total environment.

[18]  A. Younsi,et al.  Environmental impact of an urban landfill on a coastal aquifer (El Jadida, Morocco) , 2004 .

[19]  F. Çeçen,et al.  Aerobic Co-Treatment of Landfill Leachate with Domestic Wastewater , 2004 .

[20]  A. Zouboulis,et al.  A field investigation of the quantity and quality of leachate from a municipal solid waste landfill in a Mediterranean climate (Thessaloniki, Greece) , 2002 .

[21]  Michael J. Semmens,et al.  Performance analysis of a pilot-scale membrane aerated biofilm reactor for the treatment of landfill leachate , 2015 .

[22]  António Albuquerque,et al.  The influence of plants on nitrogen removal from landfill leachate in discontinuous batch shallow constructed wetland with recirculating subsurface horizontal flow , 2012 .

[23]  M. Gerardi.  Nitrification and Denitrification in the Activated Sludge Process , 2002 .

[24]  Shaohua Chen,et al.  Full-scale blending treatment of fresh MSWI leachate with municipal wastewater in a wastewater treatment plant. , 2014, Waste management.

[25]  M. Hashim,et al.  Contemporary Environmental Issues of Landfill Leachate: Assessment and Remedies , 2015 .

[26]  A. E. Greenberg,et al.  Standard methods for the examination of water and wastewater : supplement to the sixteenth edition , 1988 .

[27]  Jolanta Bohdziewicz,et al.  Application of pressure-driven membrane techniques to biological treatment of landfill leachate , 2001 .