### A

- 1 

# Annexes to the Inventory of U.S. GHG Emissions and Sinks

The following seven annexes provide additional information related to the material presented in the main body of

this report as directed in the UNFCCC Guidelines on Reporting and Review (GE.03

- 60887). Annex 1 contains an analysis

of the key categories of emissions discussed in this report and a review of the methodology used to identify those key

categories. Annex 2 describes the methodologies used to estimate CO 2 

### emissions from fossil fuel combustion, the carbon

content of fossil fuels, and the amount of carbon stored in products from non

- energy uses of fossil fuels. Annex 3

discusses the methodologies used for a number of individual source categories in greater detail than was presented in the

main body of the report and includes explicit activity data and emission factor tables. Annex 4 presents the IPCC

reference approach for estimating CO 2 

### emissions from fossil fuel combustion. Annex 5 addresses the criteria for the

inclusion of an emission source category and discusses some of the sources that are excluded from U.S. estimates. Annex

6 provides a range of additional information that is relevant t o the contents of this report. Annex 7 provides data on the

uncertainty of the emission est imates included in this report. Finally, Annex 8 provides informa tion on the QA/QC

methods and procedures used in the development of the Inventory.

ANNEX 1 Key Category Analysis

................................ ................................ ................................ ................................ ................................ 2

ANNEX 2 Methodology and Data for Estimating CO 2 

### Emissions from Fossil Fuel Combustion

................................ ............................... 27

2.1. Methodology for Estimating Emissions of CO 2 

### from Fossil Fuel Combustion

................................ ................................ ..... 27

2.2. Methodology for Estimating the Carbon Content of Fossil Fuels

................................ ................................ ......................... 59

2.3. Methodo logy for Estimating Carbon Emitted from Non

- Energy Uses of Fossil Fuels

................................ ......................... 98

ANNEX 3 Methodological Descriptions for Additional Source or Sink Categories

................................ ................................ ................... 125

3.1. Methodology for Estimating Emissions of CH 4 

### , N 2 

### O, and Indirect Greenhouse Gases from Stationary Combustion

....... 125

3.2. Methodology for Estimating Emissions of CH 4 

### , N 2 

### O, and Indirect Greenhouse Gases from Mobile Combustion and

Me thodology for and Supplemental Information on Transportation

- Related GHG Emissions

................................ ................................ . 132

3.3. Methodology for Estimating Emissions from Commercial Aircraft Jet Fuel Consumption

................................ ................. 164

3.4. Methodology for Estimating CH 4 

### Emissions from Coal Mining

................................ ................................ .......................... 168

3.5. Methodology for Estimating CH 4 

### and CO 2 

### Emissions from Natural Gas Systems

................................ ............................. 175

3.6. Methodology for Estimating CH 4 

### and CO 2 

### Emissions from Petroleum Systems

................................ ............................... 202

3.7. Methodology for Estimating CO 2, 

### N 2 

### O and CH 4 

### Emissions from the Incineration of Waste

................................ .............. 209

3.8. Methodology for Estimating Emissions from International Bunker Fuels used by the U.S. Military

................................ .. 214

3.9. Methodology for Estimating HFC and PFC Emissions from Substitution of Ozone Depleting Substances

...................... 219

3.10. Methodology for Estimating CH 4 

### Emissions from Enteric Fermentation

................................ ................................ ............ 240

3.11. Methodology for Estimating CH 4 

### and N 2 

### O Emissions from Manure Management

................................ ............................ 258

3.12. Methodology for Estimating N 2 

### O Emissions and Soil Organic C Stock Changes from Agricultural Soil Management

(Cropland and Grassland)

................................ ................................ ................................ ................................ ................................ ........ 287

3.13. Methodology for Estimating Net Carbon Stock Changes in Forest Lands Remaining Forest Lands

................................ 338

3.14. Methodology for Estimating CH 4 

### Emissions from Landfills

................................ ................................ ................................ 367

ANNEX 4 IPCC Reference Approach for Estimating CO 2 

### Emissions from Fossil Fuel Combustion

................................ ....................... 385

AN NEX 5 Assessment of the Sources and Sinks of Greenhouse Gas Emissions Not Included

................................ ............................. 395

ANNEX 6 Additional Information

................................ ................................ ................................ ................................ .............................. 397

6.1. Global Warming Potential Values

................................ ................................ ................................ ................................ ...... 397

6.2. Ozone Depleting Substance Emissions

................................ ................................ ................................ ............................. 406

6.3. Sulfur Dioxide Emissions

................................ ................................ ................................ ................................ ................... 407

6.4. Complete List of Source Categories

................................ ................................ ................................ ................................ .. 409

6.5. Constants, Units, and Conversions

................................ ................................ ................................ ................................ ... 410

6.6. Abbreviations

................................ ................................ ................................ ................................ ................................ ..... 412

6.7. Chemical Formulas

................................ ................................ ................................ ................................ ............................ 417

ANNEX 7 Uncertainty

................................ ................................ ................................ ................................ ................................ ............... 421

7.1. Overview

................................ ................................ ................................ ................................ ................................ ............ 421

7.2. Methodology and Results

................................ ................................ ................................ ................................ .................. 421

7.3. Planned Improvements

................................ ................................ ................................ ................................ ...................... 428

7.4. Additional Information on Uncertainty Analyses by Source

................................ ................................ ............................... 429

ANNEX 8 QA/QC Procedures

................................ ................................ ................................ ................................ ................................ .. 450

8.1. Background

................................ ................................ ................................ ................................ ................................ ........ 450

8.2. Purpose

................................ ................................ ................................ ................................ ................................ .............. 450

8.3. Assessment Factors

................................ ................................ ................................ ................................ .......................... 451

### A

- 202 Inventory of U.S. Greenhouse Ga s Emissions and Sinks: 1990

- 2012



# 3.6. Methodology for Estimating CH 4 

# and CO 2 

# Emissions from Petroleum Systems

The methodology for estimating CH 4 

### and non

- combustion CO 2 

### emissions from petroleum system s is based on

the 1999 EPA draft report, Estimates of Methane Emissions from the U.S. Oil Industry (EPA 1999) and the study, Methane

Emissions from the U.S. Petroleum Industry (EPA/GRI 1996). Sixty

- four activities that emit CH 4 

### and thirty activities that

emit non

- combustion CO 2 

### from petroleum systems were examined from these reports. Most of the activities analyzed

involve crude oil production field operations, which accounted for over 98 percent of total oil industry CH 4 

### emiss ions.

Crude transportation and refining accounted for the remaining CH 4 

### emissions of less than 0.4 and less than 1.3 percent,

respectively. Non

- combustion CO 2 

### emissions were analyzed for production operations and asphalt blowing in refining

operations. N on

- combustion CO 2 

### emissions from transportation operations are not included because they are negligible.

The following steps were taken to estimate CH 4 

### and CO 2 

### emissions from petroleum systems.

Step 1: Calculate Potential Methane and Carbon Dioxide

Activit y Data

Activity levels change from year to year. Some data changes in proportion to crude oil rates: production,

transportation, refinery runs. Some change in proportion to the number of facilities: oil wells, petroleum refineries. Some

factors change p roportional to both the rate and number of facilities.

For most sources, activity data for 1995 found in EPA/GRI 1996 are extrapolated to other years using publicly

available data sources. For the remaining sources, the activity data are obtained directly from publicly available data.

For both sets of data, a determination was made on a case

- by

- case basis as to which measure of petroleum

industry activity best reflects the change in annual activity. Publicly

- reported data from the Bureau of Ocean Energy

M anagement (BOEM), Energy Information Administration (EIA), American Petroleum Institute (API), the Oil & Gas

Journal (O&GJ), the Interstate Oil and Gas Compact Commission (IOGCC), and the U.S Army Corps of Engineers

(USACE) were used to extrapolate the act ivity data from the base year to each year between 1990 and 2012. Data used

include total domestic crude oil production, number of domestic crude oil wells, total imports and exports of crude oil,

total petroleum refinery crude runs, and number of oil

- pro ducing offshore platforms. The activity data for the total crude

transported in the transportation sector is not available. In this case, all the crude oil that was transported was assumed to

go to refineries. Therefore, the activity data for the refinin g sector was used also for the transportation sector. In the few

cases where no data was located, oil industry data based on expert judgment was used. In the case of non

- combustion CO 2 

### emission sources, the activity factors are the same as for CH 4 

### emissi on sources.

Potential methane factors and emission factors

The CH 4 

### emission factors for the majority of the activities are taken from the 1999 EPA draft report, which

contained the most recent and comprehensive determination of CH 4 

### emission factors for the 64 CH 4



### - emitting activities in

the oil industry at that time. Emission factors for pneumatic devices in the production sector were recalculated in 2002

using emissions data in the EPA/GRI 1996c study. The gas engine emission fact or is taken from the EPA/GRI 1996b

study. The oil tank venting emission factor is taken from the API E&P Tank Calc weighted average for API gravity less

than 45 API degrees with the distribution of gravities taken from a sample of production data from the HPDI database.

Offshore emissions from shallow water and deep water oil platforms are taken from analysis of the Gulf

- wide Offshore

Activity Data System (GOADS) report (EPA 2005, BOEMRE 2004). The emission factors were assumed to be

representative of em issions from each source type over the period 1990 through 2012. Therefore, the same emission

factors are used for each year throughout this period.

The CO 2 

### emission factors were derived from the corresponding source CH 4 

### emission factors. The amount of CO 2 

### in the crude oil stream changes as it passes through various equipment in petroleum production operations. As a result,

four distinct stages/streams with varying CO 2 

### contents exist. The four streams that are used to estimate the emissions

factors are th e associated gas stream separated from crude oil, hydrocarbons flashed out from crude oil (such as in storage

tanks), whole crude oil itself when it leaks downstream, and gas emissions from offshore oil platforms. The standard

approach used to estimate CO 2 

### emission factors was to use the existing CH 4 

### emissions factors and multiply them by a

conversion factor, which is the ratio of CO 2 

### content to methane content for the particular stream. Ratios of CO 2 

### to CH 4 

### volume in emissions are presented in Table A

- 151 . The two exceptions are the emissions factor for storage tanks, which is

estimated using API E&P Tank Calc simulation runs of tank emissions for crude oil of different gravities less than 45 API

degrees; and the emissions factor for uncontrolled asphalt blowing, which is estimated using the data and methods

provided by API (2009).

### A

- 203 Step 2: Compile Reductions Data

The methane emissions calculated in Step 1 above generally represent expected emis sions from an activity in the

absence of emissions controls, and do not take into account any use of technologies or practices that reduce emissions. To

take into account use of such technologies, data were collected on voluntary reductions. Voluntary re ductions included in

the Petroleum Sector calculations were those reported to Gas STAR for the following activities: Artificial lift: gas lift,

Artificial lift: use compression, Artificial lift: use pumping unit, Consolidate crude oil prod and water storag e tanks

, Lower

heater

- treater temperature

, Re

- inject gas for enhanced oil recovery

, Re

- inject gas into crude , and Route casinghead gas to

VRU or compressor

.

Industry partners report CH 4 

### emission reductions by project to the Natural Gas STAR Program. The reductions

from the implementation of specific technologies and practices are calculated by the reporting partners using actual

measurement data or equipment

- specific emission factors. The reductions undergo quality assurance and quality control

checks to identify errors, inconsistencies, or irregular data before being incorporated into the Inventory. T he Inventory

uses aggregated Gas STAR reductions for the petroleum sector

.

Step 3: Calculate Net Methane and Carbon Dioxide Emissions for Each Activity f or Each Year

Annual CH 4 

### emissions from each of the 64 petroleum system activities and CO 2 

### emissions from the 30 petroleum

system activities were estimated by multiplying the activity data for each year by the corresponding emission factor.

These annual em issions for each activity were then summed to estimate the total annual CH 4 

### and CO 2 

### emissions,

respectively. Gas Star reductions data is summed for each year and deducted from the potential CH 4 

### calculated in Step 1

to estimate net CH 4 

### emissions for the Inventory.

Table A

- 147

, Table A

- 148

, Table A

- 149 , and Table A

- 152 provi de 2012 activity data, emission factors, and

emission estimates and Table A

- 150 and Table A

- 153 provide a summary of emission estimates for the years 1990, 1995,

2000, and 2005 through 2012. Table A

- 151 provides the CO 2 

### content in natural gas for equipment in different crude

streams to estimate CO 2 

### emission factors using CH 4 

### emission factors.

The tables provide references for emission factors and activity data in footnotes (the lettered footnotes). The

tables also provide information on which method was used for supplying activity data for 2012 (the numbered footnotes).

Key to table notations on methods for supplying activity data for 2012 for all tables :

1. Ratios relating other factors for which activity data are available. For example, EPA (1996) found that the

number of heater treaters (a source of CH 4 

### emissions) is related to both number of producing wells and

annual production. To estimate the activity data for heater treaters, reported statistics for wells and

production were used, along with the ratios developed for EPA (1996).

2. Activity data for 2012 available from source.

3. Activity data was held constant from 1990 through 2012 based on EPA (1999).

4. 2009, 2010, or 2011 activity data are used to determine some or all of the 2012 activity data.

Table A

- 147 : 2012 CH 4 

### Emissions from Petroleum Production Field Operatio ns

Activity/Equipment 2012 EPA Inventory Values

Emission Factor Activity Data Emissions

(Bcf/yr) Emissions

(Gg/yr)

Vented Emissions 71.623 1,377 .373

Oil Tanks

7.39 scf of CH 4 /bbl crude a 1,878 MMbbl/yr (non stripper

wells) b,c,d,1,4 13.890 267.1 21

Pneumatic Devices, High Bleed

330 scfd CH 4 /device f 145,179 No. of high

- bleed

devices c,e,g,1 17.508 336. 692

Pneumatic Devices, Low Bleed

52 scfd CH 4 /device f 269,618 No. of low

- bleed

devices c,e,g,1 5.117 98.4 1 1

Chemical Injection Pumps 248 scfd CH 4 /pump h 28,702 No. of pumps g,i,p1 2.599 49.97 3

Vessel Blowdowns 78 scfy CH 4 /vessel h 189,710 No. of vessels c,g,i,1 0.015 0.285

Compressor Blowdowns 3,775 scf/yr of CH 4 /compressor h 2,582 No. of compressors c,g,i,1 0.010 0.187

Compressor Starts 8,443 scf/yr of CH 4 /compressor h 2,582 No. of compressors c,g,i,1 0.022 0.419

Stripper wells

2,345 scf/yr of CH 4 /stripper well f 315,213 No. of stripper wells

vented f,1,4 0.739 14.21

### A

- 204 Inventory of U.S. Greenhouse Ga s Emissions and Sinks: 1990

- 2012

Activity/Equipment 2012 EPA Inventory Values

Emission Factor Activity Data Emissions

(Bcf/yr) Emissions

(Gg/yr)

Well Completion Venting 733 scf/completion h 15,753 Oil well completions c,2 0.012 0.222

Well Workovers 96 scf CH 4 /workover i 40,200 Oil well workovers g,i,1 0.004 0.074

Pipeline Pigging 2.40 scfd of CH 4 /pig station j 0 No. of crude pig stations e,3

- -

Offshore Platforms, Shallow water Oil,

fugitive, vented and combusted 54,795 scfd CH 4 /platform k 1,447 No. of shallow water oil

platforms l,4 28.930 556. 353

Offshore Platforms, Deepwater oil,

fugitive, vented and combusted 260,274 scfd CH 4 /platform k 29 No. of deep water oil

platforms l,4 2.778 53.4 19

Fugitive Emissions 2.669 51.33 0

Oil Wellheads (heavy crude)

0.13 scfd/well e,m 15,565 No. of hvy. crude

wells d,g,i,1,4 0.001 0.014

Oil Wellheads (light crude) 16.6 scfd/well e,m 205,222 No. of lt. crude wells d,g,i,1,4 1.246 23.9 5 6

Separators (heavy crude)

0.15 scfd CH 4 /separator e,m 11,142 No. of hvy. crude

seps. c,g,i,1 0.001 0.012

Separators (light crude) 14 scfd CH 4 /separator e,m 101,402 No. of lt. crude seps. c,g,i,1 0.513 9.860

Heater/Treaters (light crude) 19 scfd CH 4 /heater e,m 77,166 No. of heater treaters c,g,i,1 0.541 10. 396

Headers (heavy crude) 0.08 scfd CH 4 /header e,m 13,982 No. of hvy. crude hdrs. g,i,1 0.000* 0.008

Headers (light crude) 11 scfd CH 4 /header e,m 43,344 No. of lt. crude hdrs. g,i,1 0.172 3.303

Floating Roof Tanks 338,306 scf CH 4 /floating roof tank/yr m,n 24 No. of floating roof tanks e,3 0.008 0.159

Compressors 100 scfd CH 4 /compressor e 2,582 No. of compressors c,g,i,1 0.094 1.812

Large Compressors 16,360 scfd CH 4 /compressor e 0 No. of large comprs. e,3

- -

Sales Areas 41 scf CH 4 /loading e 1,974,334 Loadings/year c,1 0.080 1.540

Pipelines NE scfd of CH 4 /mile of pipeline 14,077 Miles of gathering line o,2 NE NE

Well Drilling NE scfd of CH 4 /oil well drilled 17,774 No. of oil wells drilled c,2 NE NE

Battery Pumps 0.24 scfd of CH 4 /pump m 160,800 No. of battery pumps g,e,1 0.014 0.271

Combustion Emissions 5.188 99.76 5

Gas Engines 0.24 scf CH 4 /HP

- hr h 16,264 MMHP

- hr c,g,i,1 3.903 75.06 3

Heaters 0.52 scf CH 4 /bbl n 2

, 369.6 MMbbl/yr c,2 1.235 23.7 46

Well Drilling 2,453 scf CH 4 /well drilled m 17,774 Oil wells drilled c,2 0.044 0.838

Flares 20 scf CH 4 /Mcf flared j 305,587 Mcf flared/yr b,c,d,1,4 0.006 0.118

Process Upset Emissions 0.155 2.98 0

Pressure Relief Valves 35 scf/yr/PR valve 197,931 No. of PR valves 0.007 0.132

Well Blowouts Onshore 2.5 MMscf/blowout 59.2 No. of blowouts/yr 0.148 2.848

Voluntary Reductions 2.34 45

Total Potential Emissions 79.64 1,531.447

Total Net Emissions 77.29 1,486

a TankCALC

b EPA / ICF International (1999)

c Energy Information Administration (EIA) Monthly Energy Review

d Interstate Oil & Gas Compact Commission (IOGCC) Marginal Wells Report

e Consensus of Industrial Review Panel

f Expert Judgment

g EIA Annual Energy Review

h Gas Research Institute (GRI) / EPA (1996)

i Radian (1999)

j Canadian Association of Petroleum Producers (CAPP) (1992)

k Adapted from the Minerals Management Service (MMS) Gulfwide Offshore Activities Data System (GOADS) by ICF (2005)

l Bureau of Ocean Energy Management (BOEM)

m American Petroleum Institute (API) (1996)

n EPA, AP 42 Compilation of Air Pollutant Emission Factors

o Oil and Gas Journal (OGJ) Petroleum Economics Issue

p Percentage of chemical injection pumps (CIPs) that are gas

- driven was determined through based on an estimate provided in 1997 by Ron Rayman. F rom Dresser

Texsteam, a major manufacturer of CIPs at the time.

- Zero Emissions

* Emissions are not actually 0, but too small to show at this level of precision.

### A

- 205

Table A

- 148 : 2012 CH 4 

### Emissions from Petroleum Transportation

Activity/Equipment Emission

Factor Units Activity

Factor Units Emissions

(Bcf/yr) Emissions

(Gg/yr)

Vented Emissions 0.256 4.928

Tanks 0.021 scf CH 4 /yr/bbl of crude delivered to refineries a 5,490 MMbbl crude feed/yr b,2 0.113 2.175

Truck Loading

0.520 scf CH 4 /yr/bbl of crude transported by truck c 131.3 MMbbl crude trans. by

truck d,2 0.068 1.313

Marine Loading 2.544 scf CH 4 /1000 gal crude marine loadings c 17,518,599 1,000 gal/yr loaded e,1,4 0.045 0.857

Rail Loading

0.520 scf CH 4 /yr/bbl of crude transported by rail c 30.1 MMbbl Crude by

rail/yr d,2 0.016 0.301

Pump Station Maintenance 36.80 scf CH 4 /station/yr f 513 No. of pump stations g,1 0.000* 0.000*

Pipeline Pigging 39 scfd of CH 4 /pig station h 1,027 No. of pig stations g,1 0.015 0.281

Fugitive Emissions 0.050 0.959

Pump Stations

25 scf CH 4 /mile/yr f 51,349 No. of miles of crude

p/l g,2 0.001 0.025

Pipelines NE scf CH 4 /bbl crude transported by pipeline f 7,471 MMbbl crude piped g,2 NE NE

Floating Roof Tanks

58,965 scf CH 4 /floating roof tank/yr i 824 No. of floating roof

tanks 3 0.049 0.934

Combustion Emissions NE NE

Pump Engine Drivers 0.24 scf CH 4 /hp

- hr j NE No. of hp

- hrs NE NE

Heaters 0.521 scf CH 4 /bbl burned k NE No. of bbl Burned NE NE

Total 0.306 5.887

a API (1992)

b Energy Information Administration (EIA) Petroleum Supply Annual, Volume 1.

c EPA, AP 42 Compilation of Air Pollutant Emission Factors

d EIA Refinery Capacity Report

e EIA Monthly Energy Review

f Radian (1996)

g OGJ Petroleum Economics Issue

h CAPP (1992)

i API TANK

j GRI / EPA (1996)

k EPA / ICF International (1999)

* Emissions are not actually 0, but too small to show a t this level of precision.

NE: Not estimated for lack of data



### Table A

- 149 : 2012 CH 4 

### Emissions from Petroleum Refining

Activity/Equipment 2012 EPA Inventory Values

Emission Factor Activity Factor Emissions

(Bcf/yr) Emissions

(Gg/yr)

Vented Emissions 0.798 15.3 49

Tanks

20.6 scf CH 4 /Mbbl a 1,930 Mbbl/calendar day heavy crude

feed b,c,1 0.015 0.279

System Blowdowns

137 scf CH 4 /Mbbl c 15,040 Mbbl/calendar day refinery

feed b,2 0.751 14.44 3

Asphalt Blowing 2,555 scf CH 4 /Mbbl c 35 Mbbl/calendar day production b,2 0.033 0.627

Fugitive Emissions 0.087 1.672

Fuel Gas System 439 Mscf CH 4 /refinery/yr a 144 Refineries d,2 0.063 1.216

Floating Roof Tanks 587 scf CH 4 /floating roof tank/yr e 767 No. of floating roof tanks 3 0.000* 0.009

Wastewater Treating 1.88 scf CH 4 /Mbbl c 15,040 Mbbl/calendar day refinery

feed b,2 0.010 0.199

Cooling Towers 2.36 scf CH 4 /Mbbl c 15,040 Mbbl/calendar day refinery

feed b,2 0.013 0.249

Combustion Emissions 0.096 1.84 2

Atmospheric Distillation 3.61 scf CH 4 /Mbbl c 15,362 Mbbl/calendar day refinery 0.020 0.389

### A

- 206 Inventory of U.S. Greenhouse Ga s Emissions and Sinks: 1990

- 2012

Activity/Equipment 2012 EPA Inventory Values

Emission Factor Activity Factor Emissions

(Bcf/yr) Emissions

(Gg/yr)

feed d,2

Vacuum Distillation 3.61 scf CH 4 /Mbbl c 7,133 Mbbl/calendar day feed f,1 0.009 0.181

Thermal Operations 6.01 scf CH 4 /Mbbl c 2,295 Mbbl/calendar day feed f,1 0.005 0.097

Catalytic Cracking 5.17 scf CH 4 /Mbbl c 5,034 Mbbl/calendar day feed f,1 0.010 0.183

Catalytic Reforming 7.22 scf CH 4 /Mbbl c 3,112 Mbbl/calendar day feed f,1 0.008 0.158

Catalytic Hydrocracking 7.22 scf CH 4 /Mbbl c 1,548 Mbbl/calendar day feed f,1 0.004 0.078

Hydrorefining 2.17 scf CH 4 /Mbbl c 2,268 Mbbl/calendar day feed f,1 0.002 0.034

Hydrotreating 6.50 scf CH 4 /Mbbl c 10,401 Mbbl/calendar day feed f,1 0.025 0.474

Alkylation/Polymerization 12.6 scf CH 4 /Mbbl c 1,088 Mbbl/calendar day feed f,1 0.005 0.096

Aromatics/Isomeration 1.80 scf CH 4 /Mbbl c 1,011 Mbbl/calendar day feed f,1 0.001 0.013

Lube Oil Processing 0.00 scf CH 4 /Mbbl c 171 Mbbl/calendar day feed f,1 0.000 0.000

Engines 0.006 scf CH 4 /hp

- hr g 1,084 MMhp

- hr/yr f,1 0.006 0.119

Flares

0.189 scf CH 4 /Mbbl c,e 15,040 Mbbl/calendar day refinery

feed b,2 0.001 0.020

Total 0.981 18.86 4

a API (1992)

b EIA Petroleum Supply Annual, Volume 1.

c Radian (1996)

d EIA Petroleum Navigator

e EPA, AP 42 Compilation of Air Pollutant Emission Factors

f OGJ Refinery Worldwide Report

g GRI / EPA (1996)

* Emissions are not actually 0, but too small to show at this level of precision.



### Table A

- 150 : Summary of CH 4 

### Emissions from Petroleum Systems (Gg)

Activity 1990 1995 2000 2007 2008 2009 2010 2011 2012

Production Field Operations 1,680 1,581 1,488 1,415 1,425 1,432 1,443 1,474 1,531

Pneumatic device venting 489 463 428 398 416 419 416 428 435

Tank venting 250 226 214 193 185 202 211 222 267

Combustion & process upsets 115 106 97 90 94 94 95 98 103

Misc. venting & fugitives 799 762 726 714 706 694 700 702 703

Wellhead fugitives 26 25 22 20 24 23 22 24 24

Crude Oil Transportation 7 6 5 5 5 5 5 5 6

Refining 18 18 19 19 19 18 19 19 19

Voluntary Reductions 0.2 1.4 17 64 77 67 60 45 45

Total Potential Emissions 1,704 1,605 1,513 1,439 1,449 1,455 1,467 1,498 1,556

Total Net Emissions 1,704 1,60 4 1, 496 1, 376 1, 372 1, 388 1,4 0 7 1,4 53 1,5 11

Note: Totals may not sum due to independent rounding.



### Table A

- 151 : Ratios of CO 2 

### to CH 4 

### Volume in Emissions from Petroleum Production Field Operations

Whole Crude,

Post

- Separator Associated Gas Tank Flash Gas Offshore

Ratio %CO 2 

### / %CH 4 

### 0.052 0.020 0.017 0.004



### Table A

- 152 : 2012 CO 2 

### Emissions from Petroleum Production Field Operations and Petroleum Refining

Activity/Equipment 2012 EPA Inventory Values

Emission Factor Activity Factor Emissions

(Bcf/yr) Emissions

(Gg/yr)

Vented Emissions 7.363 389. 364

Oil Tanks 3.53 scf of CO 2 /bbl crude a 1,878 MMbbl/yr (non stripper

wells) b,c,d,1,4 6.627 350. 477

Pneumatic Devices, High Bleed 6.704 scfd CO 2 /device f 145,179 No. of high

- bleed

devices c,e,g,1 0.355 18.7 87

### A

- 207

Activity/Equipment 2012 EPA Inventory Values

Emission Factor Activity Factor Emissions

(Bcf/yr) Emissions

(Gg/yr)

Pneumatic Devices, Low Bleed 1.055 scfd CO 2 /device f 269,618 No. of low

- bleed

devices c,e,g,1 0.104 5.491

Chemical Injection Pumps 5.033 scfd CO 2 /pump h 28,702 No. of pumps g,i,1 0.053 2.788

Vessel Blowdowns 1.583 scfy CO 2 /vessel h 189,710 No. of vessels c,g,i,1 0.000* 0.016

Compressor Blowdowns 77 scf/yr of CO 2 /compressor h 2,582 No. of compressors c,g,i,1 0.000* 0.010

Compressor Starts 171 scf/yr of CO 2 /compressor h 2,582 No. of compressors c,g,i,1 0.000* 0.023

Stripper wells 48 scf/yr of CO 2 /stripper well f 315,213 No. of stripper wells

vented f,1,4 0.015 0.793

Well Completion Venting 14.87 scf/completion h 15,753 Oil well completions c,2 0.000* 0.012

Well Workovers 1.95 scf CO 2 /workover i 40,200 Oil well workovers g,i,1 0.000* 0.004

Pipeline Pigging NE scfd of CO 2 /pig station NE No. of crude pig stations NE NE

Offshore Platforms, Shallow water Oil,

fugitive, vented and combusted 358 scfd CO 2 /platform k 1,447 No. of shallow water oil

platforms l,4 0.189 10.00

Offshore Platforms, Deepwater oil,

fugitive, vented and combusted 1,701 scfd CO 2 /platform k 29 No. of deep water oil

platforms l,4 0.018 0.960

Fugitive Emissions 0.055 2.929

Oil Wellheads (heavy crude) 0.003 scfd/well e,m 15,565 No. of hvy. crude wells d,g,i,1,4 0.000* 0.001

Oil Wellheads (light crude) 0.337 scfd/well e,m 205,222 No. of lt. crude wells d,g,i,1,4 0.025 1.337

Separators (heavy crude) 0.003 scfd CO 2 /separator e,m 11,142 No. of hvy. crude seps. c,g,i,1 0.000* 0.001

Separators (light crude) 0.281 scfd CO 2 /separator e,m 101,402 No. of lt. crude seps. c,g,i,1 0.010 0.550

Heater/Treaters (light crude) 0.319 scfd CO 2 /heater e,m 77,166 No. of heater treaters c,g,i,1 0.009 0.475

Headers (heavy crude) 0.002 scfd CO 2 /header e,m 13,982 No. of hvy. crude hdrs. g,i,1 0.000* 0.000*

Headers (light crude) 0.220 scfd CO 2 /header e,m 43,344 No. of lt. crude hdrs. g,i,1 0.003 0.184

Floating Roof Tanks 17,490 scf CO 2 /floating roof

tank/yr m,n 24 No. of floating roof tanks e,3

0.000* 0.023

Compressors 2.029 scfd CO 2 /compressor e 2,582 No. of compressors c,g,i,1 0.002 0.101

Large Compressors 332 scfd CO 2 /compressor e 0 No. of large comprs. e,3 0.000 0.000

Sales Areas 2.096 scf CO 2 /loading e 1,974,334 Loadings/year c,1 0.004 0.219

Pipelines NE scfd of CO 2 /mile of

pipeline 14,077 Miles of gathering line o,2 NE NE

Well Drilling NE scfd of CO 2 /oil well drilled 17,774 No. of oil wells drilled c,2 NE NE

Battery Pumps 0.012 scfd of CO 2 /pump m 160,800 No. of battery pumps g,e,1 0.001 0.039

Process Upset Emissions 0.003 0.178

Pressure Relief Valves 1.794 scf/yr/PR valve h 197,931 No. of PR valves c,e,1 0.000* 0.019

Well Blowouts Onshore 0.051 MMscf/blowout e 59.0 No. of blowouts/yr c,e,1 0.003 0.159

Refining Emissions 0.265 14.00

Asphalt Blowing † 20,736 scf CO 2 /Mbbl m 3 5 Mbbl/calendar day

production p,2 0.265 13.998

Total 7.686 406. 468

a TankCALC

b EPA / ICF International (1999)

c EIA Monthly Energy Review

d IOGCC Marginal Wells Report

e Consensus of Industrial Review Panel

f Expert Judgement

g EIA Annual Energy Review

h GRI / EPA (1996)

i Radian (1996)

j CAPP (1992)

k Adapted from the MMS GOADS by ICF (2005)

l BOEM

m API (1996)

### A

- 208 Inventory of U.S. Greenhouse Ga s Emissions and Sinks: 1990

- 2012 n EPA, AP 42 Compilation of Air Pollutant Emi ssion Factors

o OGJ Petroleum Economics Issue

p EIA Petroleum Supply Annual, Volume 1

* Emissions are not actually 0, but too small to show at this level of precision.

† Asphalt Blowing emissions are the only significant vented emissions from the refining sector; other sources are too small to show at this level of precision.

NE: Not estimated for lack of data

Energy use CO 2 emissions not estimated to avoid double counti ng with fossil fuel combustion



### Table A

- 153 : Summary of CO 2 

### Emissions from Petroleum Systems (Gg)

Activity 1990 1995 2000 2007 2008 2009 2010 2011 2012

Production Field Operations 376 341 323 293 284 306 317 332 392

Pneumatic device venting 27 26 24 22 23 23 23 24 24

Tank venting 328 296 281 253 243 265 276 291 350

Misc. venting & fugitives 18 18 17 16 16 16 16 16 16

Wellhead fugitives 1 1 1 1 1 1 1 1 1

Refining 18 19 21 18 16 14 15 15 14

Asphalt Blowing 18 19 21 18 16 14 15 15 14

Total 394 360 344 311 300 320 332 347 406