Methane generation at open and closed landfill sites in the U.S. in 2013. Graphic: Powell, et al., 2015 / Nature Climate Change

By Seth Borenstein
22 September 2015

WASHINGTON (Associated Press) – Americans are sending more than twice as much trash to landfills as the federal government has estimated, according to a new study.

It turns out that on average America tosses five pounds of trash per person per day into its landfills, according to an analysis of figures from the same study, which is based on actual landfill measurements instead of government estimates.

For years, the U.S. Environmental Protection Agency relied on estimates to determine how much trash was being sent to landfills. But in 2010, the agency required most municipal landfills to measure and report how much trash was heading into the dumps, as part of an effort to lower heat-trapping methane emissions. Researchers at Yale University looked at the records for more than 1,200 landfills and calculated amounts, predominantly based on weights.

They figured it was 289 million tons in 2012, according to a study published Monday in the journal Nature Climate Change. For the same year, EPA estimated the figure to be 135 million tons.

The Yale team calculated that in 2013, waste sent to landfills rose to 294 million tons. With 316 million people, that comes to 1,871 pounds per person in that year, the last for which there are figures.

Jon Powell at Yale's Center for Industrial Ecology said the amount is different because of the way his team calculated it: Adding up actual measurements instead of estimates based on what businesses told government indirectly. The EPA partially funded the study.

Three outside experts said they trust the Yale numbers more than the EPA's. […]

If Powell's data is correct, Americans aren't recycling as much as authorities thought. EPA estimated that Americans recycled 34.5 percent of their waste in 2012, but if the amount of trash matches Powell calculation, the recycling rate would be 21.4 percent. [more]

Study: Twice as much trash put in landfills than estimated


ABSTRACT: Landfill disposal of municipal solid waste represents one of the largest anthropogenic global methane emission sources1, and recent policy approaches have targeted significant reductions of these emissions to combat climate change in the US (ref. 2). The efficacy of active gas collection systems in the US was examined by analysing performance data, including fire occurrence, from more than 850 landfills. A generalized linear model showed that the operating status of a landfill—open and actively receiving waste or closed—was the most significant predictor of collection system performance. Gas collection systems at closed landfills were statistically significantly more efficient (p  <  0.001) and on average 17 percentage points more efficient than those at open landfills, but open landfills were found to represent 91% of all landfill methane emissions. These results demonstrate the clear need to target open landfills to achieve significant near-term methane emission reductions. This observation is underscored by landfill disposal rates in the US significantly exceeding previously reported national estimates, with this study reporting 262 million tonnes in the year 2012 compared with 122 million tonnes in 2012 as estimated by the US Environmental Protection Agency3.

Estimates of solid waste disposal rates and reduction targets for landfill gas emissions

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