Leachate indicators of an elevated temperature landfill
Citation:
Krause, M., W. Eades, N. Detwiler, AND T. Tolaymat. Leachate indicators of an elevated temperature landfill. WASTE MANAGEMENT. Elsevier Science Ltd, New York, NY, 171:628-633, (2023). https://doi.org/10.1016/j.wasman.2023.10.001
Impact/Purpose:
Elevated temperature landfills (ETLFs) are municipal solid waste (MSW) landfills that are experiencing gas or waste temperatures above 145 degrees F (62 C). ETLFs emit large quantities of gas as well as generate more and stronger wastewater. Landfill wastewater is known as leachate. This research highlights a case study evaluation of one ETLF to understand the impact of the exothermic (heat generating) reaction on leachate volumes and characteristics and determine which leachate inorganic and organic parameters could be helpful indicators to monitor the progression of the reaction. The intended audience for this research are solid waste engineers, landfill operators, and landfill regulators.
Description:
Elevated temperature landfills (ETLFs) are municipal solid waste (MSW) landfills that have been impacted by subsurface exothermic reactions (SERs) and display unusual gas and leachate composition. Leachate quantity and quality data were analyzed to identify indicators of a SER. Annual ETLF leachate generation increased 7 times greater than the annual average from 2.04 to 14.4 m3/hectare-day (218 to 1,539 gallons/acre-day). Annual ETLF leachate generation remains about two times more than average Ohio MSW leachate generation of 1.62 +/- 1.23 m3/hectare-day (173 +/- 132 gallons/acre-day). Several general parameters such as pH, electrical conductivity (EC), and total dissolved solids (TDS) remain impacted 5 years after the reaction was first noticed. Similarly, metals such as arsenic, iron, calcium, potassium, and magnesium remain elevated. Importantly, the SER did not cause increases to compounds that would cause the leachate to be considered hazardous waste for a toxicity characteristic (e.g., lead, arsenic, etc.). However, increases to volatile organics such as acetone, benzene, and toluene make the leachate more expensive to treat. It is not clear if the volatile organic compounds are produced directly by the SERs or if they are an indicator that microbial processes -which would otherwise consume them- have been disrupted. ETLFs likely do not all undergo the same thermal reaction(s) and unlike the analysis of landfill gas composition, temporal changes in leachate constituents’ concentrations may be more important than comparing to absolute values.
