A novel simulated bio-cover was developed to facilitate the biological methane oxidation process using aged refuse and aged sludge from landfill. It was found that 78.7% and 66.9% of CH(4) could be removed, with the aged refuse: aged sludge (w/w%) ratio of 7:3 and 6:4 in bio-cover system, respectively. The maximum CH(4) removal rate could reach 100%, when the aged refuse with the disposal time more than 14 years were applied in bio-cover. Some controlled factors for the methanotrophic activity, i.e. moisture, Eh and organic matter content, were also investigated. It was found that CH(4) oxidation rate increased greatly, when the moisture content and organic matter were increased from 6.0%, 4.8% to 8.0%, 9.5%, respectively. The optimum conditions for this bio-cover system was found to be as follows: aged refuse: aged sludge ratio of 7:3, the moisture content of 8-9%, Eh of 104-108 mV and organic matter of 9.5%. (C) 2010 Elsevier Ltd. All rights reserved.