The Environmental Protection Agency (EPA) heralds it as a major step forward — requiring, for the first time, large emitters of greenhouse gases (GHGs) to report their emissions.

Question is, what's the definition of “large”?

That appears debatable, even within EPA. Back in April, EPA proposed a rule to require various economic sectors that emit GHGs, those that emit 25,000 tons/year or more of carbon dioxide (CO2) or its equivalent, to report those emissions. One of the targeted sectors was agriculture, feedyards in particular.

Based on the proposed rule, only 11 feedyards in the U.S. would have been affected — those of 89,000 head or more. Then in September, EPA released its final rule and significantly ratcheted down its definition of large. In the final rule, feedyards of 29,300 head or more are required to report — somewhere around 150 to 180 facilities.

That, says Ben Weinheimer, Texas Cattle Feeders Association (TCFA) vice president, tells you there's a lot of uncertainty in EPA's assumptions, equations and the inputs into those equations they will use to calculate how much CO2 equivalent a feedyard emits.

For feedyards, those equivalents are methane and nitrous oxide. Estimates vary slightly, but methane is considered to have about 21 times the global warming potential of CO2 and nitrous oxide about 300 times. The rule specifies that manure management systems are the target — not emissions from cattle.

“It's a calculation-based methodology,” says Weinheimer, who oversees the TCFA environmental stewardship programs that cover about a third of the nation's fed-cattle production. “EPA in the final rule has relied heavily on previous work that's been done by the International Panel on Climate Change, which is largely methodologies and assumptions that have not been developed in the U.S.”

The rule requires feedyards to keep records beginning on Jan. 1, 2010, on average animal numbers during the year and average live weight — figures that feedyards keep anyway. From that point forward, however, it gets complicated, Weinheimer says, because those figures go into a series of convoluted equations designed to arrive at a figure that estimates CO2 equivalent emissions.

So what's large?

EPA says the new reporting system will provide a better understanding of where GHGs are coming from and will guide development of policies and programs to reduce emissions. However, TCFA says, EPA admits that all of agriculture in the U.S. generates only 7% of GHGs in the country. In fact, GHG emissions from all livestock manure management systems (not just feedyards, but dairy, hog and poultry) account for 0.8% of all U.S. emissions. Manure management systems from the beef sector, according to EPA data, account for only 0.12% of total GHG emissions.

EPA has already moved to begin regulating emissions under the Clean Air Act. On Sept. 30, EPA Administrator Lisa Jackson announced a proposal requiring large industrial facilities that emit at least 25,000 tons/year of GHG to obtain construction and operating permits covering these emissions when facilities are constructed or significantly modified.

“These large facilities would include power plants, refineries and factories,” according to an EPA release. “Small business, such as farms and restaurants, and many other types of small facilities, would not be included in these requirements.”

While it's still just a reporting rule for feedyards, Weinheimer asks why EPA needs to know feedyard emissions. “If regulation wasn't their motive for requesting the data, then what are they going to do with it?”

What's frustrating in this whole process, Weinheimer says, is that regulators appear to be laying the groundwork for the first step in what could become another very lengthy regulatory process. “When you start reporting, very quickly that gives you the basis for permitting, for emissions fees, for prescriptive measures on emissions reductions. And all that can be done with very little scientific basis and absolutely no consideration for the costs to the cattle producer,” he adds.