* — * U.S. Environmental Protection Agency	18-P-0129
March 16, 2018
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	 \ Office of Inspector General
At a Glance
Why We Did This Review
The U.S. Environmental
Protection Agency's (EPA's)
Office of the Inspector General
conducted this review in
response to a hotline complaint
alleging that the EPA used
results from two flawed studies
to estimate methane emissions
and make policy decisions
regarding oil and natural gas
production. The complaint
alleged that two methane
emissions studies conducted by
the University of Texas-Austin
(UT-Austin), and sponsored by
the Environmental Defense
Fund (EDF), were flawed due
to a malfunction in one of the
measurement devices called
a Hi Flow Sampler.
Our objectives were to
determine (1) how the EPA
estimates methane emissions
from oil and natural gas
production, including whether
the EPA used results from the
two EDF/UT-Austin studies
to estimate emissions; and
(2) whether concerns about
technical or other problems with
the studies were identified or
brought to the EPA's attention,
and how the EPA addressed
and resolved those concerns.
EPA Did Not Use Allegedly Flawed Studies to Estimate
Methane Emissions or Set New Source Performance
Standards for Oil and Natural Gas Production
Methane is a potent
greenhouse gas
emitted from natural
and industrial sources,
including oil and natural
gas production facilities.
What We Found
The Inventory of U.S. Greenhouse Gas Emissions
and Sinks (Greenhouse Gas Inventory) reflects the
EPA's official nationwide estimate for greenhouse
gas emissions from all man-made sources,
including those from oil and natural gas production.
The inventory is developed using a variety of data
sources and emission estimation methodogies.
One source of data for the inventory is emissions and activity data reported to the
EPA under its Greenhouse Gas Reporting Program. This reporting program
requires large emission sources and fuel suppliers to calculate and report their
greenhouse gas emissions data to the EPA.
The EPA used its Greenhouse Gas Inventory development process to consider
information related to the EDF/UT-Austin studies and the Hi Flow Sampler. In
memorandums issued in 2015 and 2016, inventory staff requested expert and
public feedback on specific aspects of the EDF/UT-Austin studies, how data could
potentially be used for the inventory, and potential problems with the Hi Flow
Sampler.
The EPA ultimately did not make any methodological revisions to the Greenhouse
Gas Inventory or to the Greenhouse Gas Reporting Program based on the
EDF/UT-Austin studies, and data from the studies have not been incorporated into
the inventory. In addition, the EPA did not use any data from the EDF/UT-Austin
studies to set the final 2016 New Source Performance Standards to limit methane
emissions from the oil and natural gas industry.
We make no recommendations.
This report addresses the
following:
• Improving air quality.
Send all inquiries to our public
affairs office at (202) 566-2391
or visit www.epa.gov/oiq.
Listing of OIG reports.

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