[Federal Register Volume 78, Number 36 (Friday, February 22, 2013)]
[Page 12310]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2013-04142]




Inventory of U.S. Greenhouse Gas Emissions and Sinks: 1990-2011

AGENCY: Environmental Protection Agency (EPA).

ACTION: Notice of document availability and request for comments.


SUMMARY: The Draft Inventory of U.S. Greenhouse Gas Emissions and 
Sinks: 1990-2011 is available for public review. Annual U.S. emissions 
for the period of time from 1990 through 2011 are summarized and 
presented by source category and sector. The inventory contains 
estimates of carbon dioxide (CO2), methane (CH4), 
nitrous oxide (N2O), hydrofluorocarbons (HFC), 
perfluorocarbons (PFC), and sulfur hexafluoride (SF6) 
emissions. The inventory also includes estimates of carbon fluxes in 
U.S. agricultural and forest lands. The technical approach used in this 
report to estimate emissions and sinks for greenhouse gases is 
consistent with the methodologies recommended by the Intergovernmental 
Panel on Climate Change (IPCC), and reported in a format consistent 
with the United Nations Framework Convention on Climate Change (UNFCCC) 
reporting guidelines. The Inventory of U.S. Greenhouse Gas Emissions 
and Sinks: 1990-2011 is the latest in a series of annual U.S. 
submissions to the Secretariat of the UNFCCC.

DATES: To ensure your comments are considered for the final version of 
the document, please submit your comments within 30 days of the 
appearance of this notice. However, comments received after that date 
will still be welcomed and be considered for the next edition of this 

ADDRESSES: Comments should be submitted to Mr. Leif Hockstad at: 
Environmental Protection Agency, Climate Change Division (6207J), 1200 
Pennsylvania Ave., NW., Washington, DC 20460, Fax: (202) 343-2359. You 
are welcome and encouraged to send an email with your comments to 
[email protected].

FOR FURTHER INFORMATION CONTACT: Mr. Leif Hockstad, Environmental 
Protection Agency, Office of Air and Radiation, Office of Atmospheric 
Programs, Climate Change Division, (202) 343-9432, 
[email protected].

SUPPLEMENTARY INFORMATION: For this year's public review, EPA is 
calling attention to two specific areas where interested stakeholders 
could provide feedback to improve the quality of the emission 
estimates. First, EPA is seeking comments on approaches for using 
facility-level data reported under EPA's Greenhouse Gas Reporting 
Program (GHGRP), particularly data from reporters that began reporting 
in 2011. For selected source categories, EPA could use data elements 
reported under the GHGRP, such as facility-level data that can be 
aggregated at the national level, to derive country-specific emission 
factors for use in estimating industrial process emissions. Categories 
with GHGRP-related updates under consideration include nitric acid, 
petrochemical production, phosphoric acid, titanium dioxide, lime 
production, and several fluorinated gas categories. Interested 
stakeholders should review detailed methodological approaches in 
Chapter 4 (Industrial Processes) of the report. Depending on 
stakeholder feedback, EPA may include revised estimates in the final 
published inventory report that use these emission factors derived from 
the specified GHGRP data elements.
    The second area is the natural gas sector, which in recent years 
has experienced significant growth and changes in industry practices. 
EPA recently solicited and received new information and data related to 
emissions estimates for the oil and gas industry through a variety of 
mechanisms, including the formal public notice and comment process of 
the oil and gas New Source Performance Standards (NSPS) to control 
VOCs, a stakeholder workshop on the natural gas sector emissions 
estimates, and data submitted under the GHGRP. In developing the draft 
inventory report for this public comment period, EPA carefully 
evaluated relevant information, and has made updates to two key 
sources: liquids unloading, and completions with hydraulic fracturing 
and refracturing. EPA also made additional changes to the report to 
allow for more transparency. EPA seeks feedback on these updates, and 
on incorporation of GHGRP data, and requests recommendations for 
improving the overall quality of the inventory report to be finalized 
in April 2013, as well as subsequent Inventory reports.
    The draft report can be obtained by visiting the U.S. EPA's Climate 
Change Site at: http://www.epa.gov/climatechange/ghgemissions/usinventoryreport.html.

    Dated: February 14, 2013.
Gina McCarthy,
Assistant Administrator, Office of Air and Radiation.
[FR Doc. 2013-04142 Filed 2-21-13; 8:45 am]