EPA’s Greenhouse Gas Inventory needs some fixing

Methane pollution from oil and gas operations is dangerously high, and the continued expansion of production through fracking in places like the Marcellus and Utica in Pennsylvania, Ohio, and West Virginia in the northeast and Permian in New Mexico and Texas in the southwest is making the climate threat worse.  

Voluntary commitments by companies to cut methane pollution have proven inadequate, at best, as was illustrated when only 10 out of approximately 8,0000 oil and gas producers signed onto a voluntary program in 2016.  At worst, these commitments are sleight-of-hand public relations trick to delay uniform, national methane rules in hopes of eking out a bit more immediate profit.

The threat is from methane pollution is real.  It is extensive and pervasive along the whole oil and gas supply chain.  And remedies to eliminate it must be enacted immediately. This is the climate reality regardless of how industry tries to spin the numbers of methane pollution from the U.S. Greenhouse Gas Inventory, which is expected to be released in its final form this week.

The most important thing to know about the U.S. Greenhouse Gas Inventory is that it is an estimate including assumptions that equipment works properly, and self-reporting from only those operations that admit methane releases over a certain threshold.  That is part of the reason why its methodology, and results have have been repeatedly challenged by experts here and here and here.  Oh, and here.

One of the most extensive studies conducted on the question of methane pollution leaks and emissions from oil and gas infrastructure in the U.S., published in the journal Science, found that the magnitude of methane pollution released is 60% higher than the EPA estimate.  That is an outrageously large discrepancy.

Were you to get a second opinion from another doctor about toxins found in your body and the results of your second screening were 60% higher than the first doctor, you would want to file a malpractice lawsuit.  Yet, year in and year out, with the help of industry, the EPA greenhouse gas estimates are reported as the gospel truth.

Just this week, a new analysis from the Environmental Defense Fund was released showing that oil and gas companies in New Mexico emit more than double the amount of methane than what EDF estimated just two years ago.  The study also shows methane pollution approximately five times more than EPA suggests–on par with the discrepancy published in the journal Science.

Generally speaking, there are three main challenges with estimating methane pollution.  The first has to do with the large number of oil and gas sources that leak and release methane pollution.  As New Mexico Land Office Commissioner recounted when touring operations in the Permian, “‘We went to some older operations, some newer operations, some [wells operated] by some smaller companies, some by larger companies.’ Not one facility they visited didn’t have emissions pouring out from pipes or seeping out of valves.” The second is the varying approaches to measurement and making estimates.  The third is accounting for abnormal operating conditions, or the methane pollution leaking from a piece of equipment that isn’t functioning properly.

The EPA’s answer to the challenge of conducting an inventory on methane leaks and releases from so many oil and gas facilities is, for the most part, to choose not to directly measure methane pollution.  Instead the EPA models oil and gas methane pollution. But the model is based on industry self-reporting and then extrapolated, and the model hasn’t been updated with the latest science.

Not even the companies are required to directly measure the methane pollution from their own facilities.  Instead, the data that is submitted to the EPA comes in the form of company estimates based on something the EPA calls “multiplying emissions factors.”  In layman’s terms, this means counting the number of a specific piece of equipment, finding a predetermined standard rate of leakage number on a table provided by the EPA, and then multiplying that to a good guess on how much methane pollution is leaking into our atmosphere.

It is a approach that is far from perfect and very problematic if the U.S. Greenhouse Gas Inventory is suggested to be comprehensive.  It is not.

EPA’s choice not to conduct any direct measurements puts a lot weight on its emission factors.  A criticism here is that many emission factors have not been updated since a 1996 GRI study. Pieces of equipment that are still given methane pollution estimates based on outdated emissions factors include well pad equipment, dehydrator vents, blowdowns, and engine exhaust.  With most methane pollution leaked and released from oil and gas happening at the production phase, these emissions factors should be most prioritized to get their leaking rates right.

The EPA also does not require that all oil and gas companies report on all of their facilities.  In fact, the exclusion of any reporting requirement for facilities under a certain threshold results in a majority of operators having no legal obligation to submit data to the EPA.  

So, for the U.S. Greenhouse Gas Inventory, we have an (1) estimate (2) with some outdated numbers (3) based upon self-reported data from (3) a minority of operators in the United States.  

That total of those factors add up to the largest problem with the EPA’s approach.  This has to do with the third challenge of capturing abnormal operating conditions. One study conducted in the Barnett Shale basin in 2015 found that 10% of sources account for 90% of methane pollution.  The reason: equipment not functioning or being used properly.

If the majority of methane pollution is caused from abnormal operating conditions, then EPA’s methodology is underestimating the actual amount of methane pollution coming from oil and gas operations.

So, if the current approach to estimating methane pollution for the U.S. Greenhouse Gas Inventory is insufficient, how can we determine the scale of the threat?  Well, the two studies mentioned here focused entirely on making determinations of methane pollution with an improved approach to measure. The data from these studies is more reliable than the EPA annual report because they calculate estimates use multiple methodologies including direct measurement on the ground and sampling of methane concentrations from the air.  One of the studies also factored in statistics on the high emitting equipment that is often at fault for running on abnormal operating conditions.

So, this is why every story covering the U.S. Greenhouse Gas Inventory should come with an asterisk and disclaimer stating that the measurement of methane pollution from the oil and gas supply line remains highly uncertain.

The oil and gas industry isn’t going to note that, for sure.

We will have to address these issues with EPA’s estimates on methane pollution because the consequence of not knowing the quantity of methane released by oil and gas in the U.S. is life-threatening.  Uncertainty about a greenhouse gas that is 86 times more potent than carbon dioxide at warming the planet over a 20 year timespan is not something no one can afford. We don’t have room for the kind of error the EPA estimate may be making when the best climate science has given the world a little more than a decade to everything it can to prevent the worst case scenario from happening.  

The least we can all do it to acknowledge the uncertainty.

The worst thing we can do is be complicit with some in the oil and gas industry at perpetuating the myth that the EPA annual report is comprehensive and a document from which U.S. methane policy should be primarily decided.  

Because the consequence of perpetuating this myth is disastrous.  With the wrong information investors will continue to invest in oil and gas infrastructure not knowing the scale of risk of the investments.  Decision makers may think the problem to be significantly less urgent that it really is. And industry will be allowed to continue to brand natural gas as a “clean” energy source while escaping accountability on their failure to account for how much of this powerful climate pollutant they’re actually responsible for adding to the atmosphere.

The U.S. Greenhouse Gas Inventory estimates for 2017 must be submitted to the United Nations by April 15th.