Appendix A to the 2015 Supporting Statement for Subpart W

Dated November 2014 

New Subpart W Reporting Elements
Emission Source Citation Reference Proposed Rule Text 

Natural Gas Pneumatic Devices 

§98.236(b)(1)(i) The total number of devices, determined according to §98.233(a)(1) and (a)(2). 

Natural Gas Pneumatic Devices 

§98.236(b)(1)(ii)(A) A list of the well ID numbers associated with the devices that are counted (for the onshore petroleum and natural 

gas production industry segment only). 

Natural Gas Pneumatic Devices 

§98.236(b)(1)(ii)(A) The number of devices reported in paragraph (b)(1)(i) of this section that are counted. 

Natural Gas Pneumatic Devices 

§98.236(b)(1)(ii)(B) A list of the well ID numbers associated with the devices that are estimated (not counted) (for the onshore 

petroleum and natural gas production industry segment only). 

Natural Gas Pneumatic Devices 

§98.236(b)(1)(ii)(B) The number of devices reported in paragraph (b)(1)(i) of this section that are estimated (not counted). 

Natural Gas Pneumatic Devices 

§98.236(b)(1)(ii)(C) Whether the calendar year is the first calendar year of reporting or the second calendar year of reporting 

Natural Gas Pneumatic Devices 

§98.236(b)(2) For each type of pneumatic device, the estimated average number of hours in the calendar year that the natural gas 

pneumatic devices reported in paragraph (b)(1)(i) of this section were operating in the calendar year (“Tt” in 

Equation W-1 of this subpart). 

Natural Gas Pneumatic Devices 

§98.236(b)(3) Annual CO2 emissions, in metric tons CO2, for the natural gas pneumatic devices combined, calculated using 

Equation W-1 of this subpart and § 98.233(a)(4), and reported in paragraph (b)(1)(i) of this section 

Natural Gas Pneumatic Devices 

§98.236(b)(4) Annual CH4 emissions, in metric tons CH4, for the natural gas pneumatic devices combined, calculated using 

Equation W-1 of this subpart and § 98.233(a)(4), and reported in paragraph (b)(1)(i) of this section 

Natural Gas Pneumatic Pump Venting 

§98.236(c)(1) Count of natural gas driven pneumatic pumps 

Natural Gas Pneumatic Pump Venting 

§98.236(c)(2) A list of the well ID numbers associated with the natural gas driven pneumatic pumps (for the onshore petroleum 

and natural gas production industry segment only). 

Natural Gas Pneumatic Pump Venting 

§98.236(c)(3) Average estimated number of hours in the calendar year the pumps were operational (“T” in Equation W-2 of this 

subpart).. 

Natural Gas Pneumatic Pump Venting 

§98.236(c)(4) Annual CO2 emissions, in metric tons CO2, for all natural gas driven pneumatic pumps combined, calculated 

according to §98.233(c)(1) and (c)(2) 

Natural Gas Pneumatic Pump Venting 

§98.236(c)(5) Annual CH4 emissions, in metric tons CH4, for all natural gas driven pneumatic pumps combined, calculated 

according to §98.233(c)(1) and (c)(2) 

Acid Gas Removal §98.236(d)(1)(i) A unique name or ID number for acid gas removal unit. Acid Gas Removal §98.236(d)(1)(ii) A list of the well ID numbers associated with the acid gas removal units (for the onshore petroleum and natural ga

production industry segment only).. 

Acid Gas Removal §98.236(d)(1)(iii) Total feed rate entering the acid gas removal unit, using a meter or engineering estimate based on process 

knowledge or best available data, in million cubic feet per year. 

Acid Gas Removal §98.236(d)(1)(iv) The calculation method used to calculate CO2 emissions from the acid gas removal unit, as specified in §98.233(d)
Emission Source Citation Reference Proposed Rule Text 

Acid Gas Removal §98.236(d)(1)(v) Whether any CO2 emissions are recovered and transferred outside the facility Acid Gas Removal §98.236(d)(1)(v) If any CO2 emissions from the acid gas removal unit were recovered and transferred outside the facility, then you 

must report the annual quantity of CO2, in metric tons CO2,that was recovered and transferred outside the facility. 

Acid Gas Removal §98.236(d)(1)(vi) Annual CO2 emissions, in metric tons CO2, from the acid gas removal unit, calculated using any one of the 

calculation methods specified in §98.233(d) and as specified in §98.233(d)(10) and (11). 

Acid Gas Removal §98.236(d)(1)(vii) Sub-basin ID that best represents the wells and/or equipment supplying gas to the unit. Acid Gas Removal §98.236(d)(2)(i)(A) For each unit for which Calculation Methodology 1 or 2 in §98.233(d) is used, annual average volumetric fraction 

of CO2 in the vent gas exiting the acid gas removal unit.

Acid Gas Removal §98.236(d)(2)(i)(B) For each unit for which Calculation Methodology 1 or 2 in §98.233(d) is used, annual volume of gas vented from 

the acid gas removal unit, in cubic feet. 

Acid Gas Removal §98.236(d)(2)(ii)(A) For each unit for which Calculation Methodology 3 in §98.233(d) is used, indicate which equation was used 

(Equation W-4A or W-4B). 

Acid Gas Removal §98.236(d)(2)(ii)(B) For each unit for which Calculation Methodology 3 in §98.233(d) is used, annual average volumetric fraction of 

CO2 in the natural gas flowing out of the acid gas removal unit, as specified in Equation W-4A or Equation W-4B 

of this subpart. 

Acid Gas Removal §98.236(d)(2)(ii)(C) For each unit for which Calculation Methodology 3 in §98.233(d) is used, annual average volumetric fraction of 

CO2 content in natural gas flowing into the acid gas removal unit, as specified in Equation W-4A or Equation W4B of this subpart. 

Acid Gas Removal §98.236(d)(2)(ii)(D) For each unit for which Calculation Methodology 3 in §98.233(d) is used, the natural gas flow rate used, as 

specified in Equation W-4A of this subpart, reported as either total annual volume of natural gas flow into the acid 

gas removal unit in cubic feet at actual conditions; or total annual volume of natural gas flow out of the acid gas 

removal unit, as specified in Equation W-4B of this subpart, in cubic feet at actual conditions,. 

Acid Gas Removal §98.236(d)(2)(iii)(A) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the name of the simulation software 

package used 

Acid Gas Removal §98.236(d)(2)(iii)(B) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the natural gas feed temperature, in 

degrees Fahrenheit. 

Acid Gas Removal §98.236(d)(2)(iii)(C) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the natural gas feed pressure, in pounds 

per square inch. 

Acid Gas Removal §98.236(d)(2)(iii)(D) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the natural gas flow rate, in standard 

cubic feet per minute. 

Acid Gas Removal §98.236(d)(2)(iii)(E) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the acid gas content of the feed natural 

gas, in mole percent. 

Acid Gas Removal §98.236(d)(2)(iii)(F) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the acid gas content of the outlet natura

gas, in mole percent. 
Emission Source Citation Reference Proposed Rule Text 

Acid Gas Removal §98.236(d)(2)(iii)(G) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the unit operating hours, excluding 

downtime for maintenance or standby, in hours per year. 

Acid Gas Removal §98.236(d)(2)(iii)(H) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the exit temperature of the natural gas, 

in degrees Fahrenheit. 

Acid Gas Removal §98.236(d)(2)(iii)(I) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the solvent pressure, in pounds per 

square inch. 

Acid Gas Removal §98.236(d)(2)(iii)(J) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the solvent temperature, in degrees 

Fahrenheit. 

Acid Gas Removal §98.236(d)(2)(iii)(K) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the solvent circulation rate, in gallons 

per minute. 

Acid Gas Removal §98.236(d)(2)(iii)(L) For each unit for which Calculation Methodology 4 in §98.233(d) is used, the solvent weight, in pounds per gallonDehydrators §98.236(e)(1)(i) Unique name or ID number for dehydrators. Dehydrators §98.236(e)(1)(ii) For the onshore petroleum and natural gas production segment only, a list of well ID number(s) associated with th

dehydrators. 

Dehydrators §98.236(e)(1)(iii) Dehydrator feed natural gas flow rate, in million standard cubic feet per day, determined by engineering estimate 

based on best available data. 

Dehydrators §98.236(e)(1)(iv) Dehydrator feed natural gas water content, in pounds per million standard cubic feet. Dehydrators §98.236(e)(1)(v) Dehydrator outlet natural gas water content, in pounds per million standard cubic feet. Dehydrators §98.236(e)(1)(vi) Dehydrator absorbent circulation pump type (e.g., natural gas pneumatic, air pneumatic, or electric). Dehydrators §98.236(e)(1)(vii) Dehydrator absorbent circulation rate, in gallons per minute. Dehydrators §98.236(e)(1)(viii) Type of absorbent (e.g., triethylene glycol (TEG), diethylene glycol (DEG), or ethylene glycol (EG)). Dehydrators §98.236(e)(1)(ix) Whether stripper gas is used in dehydrator. Dehydrators §98.236(e)(1)(x) Whether a flash tank separator is used in dehydrator. Dehydrators §98.236(e)(1)(xi) Total time the dehydrator is operating, in hours. Dehydrators §98.236(e)(1)(xii) Temperature of the wet natural gas, in degrees Fahrenheit. Dehydrators §98.236(e)(1)(xiii) Pressure of the wet natural gas, in pounds per square inch gauge. Dehydrators §98.236(e)(1)(xiv) Mole fraction of CH4 in wet natural gas. Dehydrators §98.236(e)(1)(xv) Mole fraction of CO2 in wet natural gas. Dehydrators §98.236(e)(1)(xvi) For each glycol dehydrator, whether any dehydrator emissions are vented to the atmosphere without being routed 

to a flare or regenerator firebox. 

Dehydrators §98.236(e)(1)(xvii) Whether any dehydrator emissions are vented to a flare or regenerator firebox/fire tubes. Dehydrators §98.236(e)(1)(xvii)(A) If any emissions are vented to a flare or regenerator firebox/fire tubes, annual CO2 emissions, in metric tons CO2, 

for the dehydrator, calculated according to § 98.233(e)(6). 
Emission Source Citation Reference Proposed Rule Text 

Dehydrators §98.236(e)(1)(xvii)(B) If any emissions are vented to a flare or regenerator firebox/fire tubes, annual CH4 emissions, in metric tons CH4, 

for the dehydrator, calculated according to § 98.233(e)(6). 

Dehydrators §98.236(e)(1)(xvii)(C) If any emissions are vented to a flare or regenerator firebox/fire tubes, annual N2O emissions, in metric tons N2O, 

for the dehydrator, calculated according to § 98.233(e)(6). 

Dehydrators §98.236(e)(1)(xviii) For each glycol dehydrator, whether any dehydrator emissions are vented to the atmosphere without being routed 

to a flare or regenerator firebox. 

Dehydrators §98.236(e)(1)(xviii)(A) If any emissions are not routed to a flare or regenerator firebox/fire tubes, annual CO2 emissions, in metric tons 

CO2, for the dehydrator when not venting to a flare or regenerator firebox/fire tubes, calculated according to § 

98.233(e)(1) and (e)(5). 

Dehydrators §98.236(e)(1)(xviii)(B) If any emissions are not routed to a flare or regenerator firebox/fire tubes, annual CH4 emissions, in metric tons 

CH4, for the dehydrator when not venting to a flare or regenerator firebox/fire tubes, calculated according to § 

98.233(e)(1) and (e)(5). 

Dehydrators §98.236(e)(1)(xix) For each glycol dehydrator, sub-basin ID that best represents the wells and/or equipment supplying gas to the 

dehydrator. 

Dehydrators §98.236(e)(2)(i) The total number of glycol dehydrators at the facility with an annual average daily natural gas throughput less than 

0.4 million standard cubic feet per day. 

Dehydrators §98.236(e)(2)(ii) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers associated with 

the dehydrators at the facility. 

Dehydrators §98.236(e)(2)(iii) For the onshore petroleum and natural gas production segment only, a list of the associated well ID numbers for 

glycol dehydrators at the facility that were vented to a vapor recovery device. 

Dehydrators §98.236(e)(2)(iii) For the onshore petroleum and natural gas production industry segment only, a list of the associated well ID 

numbers for each glycol dehydrator at the facility that was vented to a vapor recovery device. 

Dehydrators §98.236(e)(2)(iv) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd, the number of 

dehydrators venting to a control device other than a vapor recovery device or a flare or regenerator firebox/fire 

tubes. 

Dehydrators §98.236(e)(2)(iv) For the onshore petroleum and natural gas production segment only, a list of the associated well ID numbers for 

each type of control device (other than a vapor recovery device, flare, or regenerator firebox/fire tubes) to which a 

glycol dehydrator at the facility was vented. 

Dehydrators §98.236(e)(2)(v) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd, whether any 

glycol dehydrator emissions are vented to a flare or regenerator firebox/fire tubes. 

Dehydrators §98.236(e)(2)(v)(A) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd and vent to a 

flare or regenerator firebox, the total number of dehydrators. 

Dehydrators §98.236(e)(2)(v)(B) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd and vent to a 

flare or regenerator firebox, annual CO2 emissions, in metric tons CO2, for the dehydrators reported in paragraph 

(e)(2)(iv)(A) of this section, calculated according to § 98.233(e)(6). 
Emission Source Citation Reference Proposed Rule Text 

Dehydrators §98.236(e)(2)(v)(C) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd and vent to a 

flare or regenerator firebox, annual CH4 emissions, in metric tons CH4, for the dehydrators reported in paragraph 

(e)(2)(iv)(A) of this section, calculated according to § 98.233(e)(6). 

Dehydrators §98.236(e)(2)(v)(D) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd and vent to a 

flare or regenerator firebox, annual N2O emissions, in metric tons N2O, for the dehydrators reported in paragraph 

(e)(2)(iv)(A) of this section, calculated according to § 98.233(e)(6). 

Dehydrators §98.236(e)(2)(vi)(A) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd not vented to a 

flare or regenerator firebox/fire tubes, annual CO2 emissions in metric tons CO2, for emissions from all dehydrator

reported in paragraph (e)(2)(i) of this section that were not vented to a flare or regenerator firebox/fire tubes, 

calculated according to § 98.233(e)(2), (e)(4), and (e)(5), where emissions are added together for all such 

dehydrators. 

Dehydrators §98.236(e)(2)(vi)(B) For glycol dehydrators with an annual average daily natural gas throughput less than 0.4 MMscfd not vented to a 

flare or regenerator firebox/fire tubes, annual CH4 emissions in metric tons CO2, for emissions from all dehydrator

reported in paragraph (e)(2)(i) of this section that were not vented to a flare or regenerator firebox/fire tubes, 

calculated according to § 98.233(e)(2), (e)(4), and (e)(5), where emissions are added together for all such 

dehydrators. 

Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant, the total number of dehydrators at the facility. Dehydrators §98.236(e)(3)(i) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers associated with 

the dehydrators using desiccant at the facility. 

Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant, the total number of dehydrators venting to a vapor recovery device. Dehydrators §98.236(e)(3)(i) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers associated with 

the dehydrators using desiccant and venting to a vapor recovery device at the facility. 

Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant, the number of dehydrators venting to a control device other than a vapor 

recovery device or a flare or regenerator firebox/fire tubes. 

Dehydrators §98.236(e)(3)(i) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers associated with 

the dehydrators at the facility using desiccant and venting to a control device other than a vapor recovery device or a flare or regenerator firebox/fire tubes. 

Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant and vent to a flare or regenerator firebox, the total number of dehydrators. Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant and vent to a flare or regenerator firebox, annual CO2 emissions, in metric tons 

CO2, for the dehydrators reported in paragraph (e)(2)(iv)(A) of this section, calculated according to § 98.233(e)(6)

Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant and vent to a flare or regenerator firebox, annual CH4 emissions, in metric tons 

CH4, for the dehydrators reported in paragraph (e)(2)(iv)(A) of this section, calculated according to § 98.233(e)(6)

Dehydrators §98.236(e)(3)(i) For dehydrators that use desiccant and vent to a flare or regenerator firebox, annual N2O emissions, in metric tons 

N2O, for the dehydrators reported in paragraph (e)(2)(iv)(A) of this section, calculated according to § 98.233(e)(6)
Emission Source Citation Reference Proposed Rule Text 

Dehydrators §98.236(e)(3)(ii) Annual CO2 emissions, in metric tons CO2, for emissions from all desiccant dehydrators reported under paragraph 

(e)(3)(i) of this section that are not venting to a flare or regenerator firebox/fire tubes, calculated according to § 

98.233(e)(3), (e)(4), and (e)(5), and summing for all such dehydrators. 

Dehydrators §98.236(e)(3)(iii) Annual CH4 emissions, in metric tons CH4, for emissions from all desiccant dehydrators reported in paragraph 

(e)(3)(i) of this section that are not venting to a flare or regenerator firebox/fire tubes, calculated according to § 

98.233(e)(3), (e)(4), and (e)(5), and summing for all such dehydrators. 

Liquids Unloading §98.236(f)(1)(ii) A list of the well ID numbers associated with each sub-basin well tubing diameter and pressure group ID for which 

you used Calculation Method 1 to calculate natural gas emissions from well venting for liquids unloading. 

Liquids Unloading §98.236(f)(2)(i) A list of the well ID numbers associated with each sub-basin for which you used Calculation Method 2 or 3 to 

calculate natural gas emissions from well venting for liquids unloading. 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g) Whether the facility had any oil well completions or workovers with hydraulic fracturing in the calendar year. 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(1) For each completion or workover and well type combination, the sub-basin ID. 

Completions and Workovers with Hydraulic Fracturing - Gas and Oil Wells 

§98.236(g)(1) A list of the well ID numbers associated with each sub-basin that had completions or workovers with hydraulic 

fracturing during the calendar year 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(2) For each completion or workover and well type combination, the well type (horizontal or vertical, gas well or oil 

well). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(3) For each oil well completion or workover and well type combination, the total number of completions or 

workovers in the sub-basin and well type combination category. 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(4) For each oil well completion or workover and well type combination, the calculation method used. 
Emission Source Citation Reference Proposed Rule Text 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(5)(i) If you used Equation W-10A to calculate annual volumetric total gas emissions, the cumulative gas flowback time

in hours, for each sub-basin, from when gas is first detected until sufficient quantities are present to enable 

separation (sum of “Tp,i” in Equation W-10A). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(5)(i) If you used Equation W-10A to calculate annual volumetric total gas emissions, the cumulative flowback time, in 

hours, for each sub-basin, after sufficient quantities of gas are present to enable separation (sum of “Tp,s” in 

Equation W-10A). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(5)(ii) If you used Equation W-10A to calculate annual volumetric total gas emissions, the measured flowback rate for th

measured well(s), in standard cubic feet per hour, for each sub-basin (average of “FRs,p” in Equation W-12A). 

Completions and Workovers with Hydraulic Fracturing - Gas and Oil Wells 

§98.236(g)(5)(ii) The well ID numbers of the wells for which flowback rate is measured. 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(5)(iii)(A) If you used Equation W-12C to calculate the average gas production rate for an oil well, the gas to oil ratio for the 

well in standard cubic feet of gas per barrel of oil (“GORp” in Equation W-12C). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(5)(iii)(B) If you used Equation W-12C to calculate the average gas production rate for an oil well, the volume of oil 

produced during the first 30 days of production after completions of each newly drilled well or well workover using hydraulic fracturing, in barrels (“Vp” in Equation W-12C). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(6)(i) If you used Equation W-10B to calculate annual volumetric total gas emissions for completions that vent gas to th

atmosphere, the vented natural gas volume, in standard cubic feet per hour, for each well in the sub-basin (“FVs,p” 

in Equation W-10B). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(6)(ii) If you used Equation W-10B to calculate annual volumetric total gas emissions for completions that vent gas to th

atmosphere, the flow rate, in standard cubic feet per hour, at the beginning of the period of time when sufficient 

quantities of gas are present to enable separation (“FRp,i” in Equation W-10B). 

Completions and Workovers with Hydraulic Fracturing - Gas and Oil Wells 

§98.236(g)(6)(iii) If you used Equation W-10B to calculate annual volumetric total gas emissions for completions that vent gas to th

atmosphere, the well ID number for which vented natural gas volume was measured. 
Emission Source Citation Reference Proposed Rule Text 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(7) For each oil well completion or workover and well type combination, annual gas emissions, in standard cubic feet 

(“Es,n” in Equation W-10A or W-10B). 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(8) For each oil well completion or workover and well type combination, annual CO2 emissions, in metric tons CO2. 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(9) For each oil well completion or workover and well type combination, annual CH4 emissions, in metric tons CH4. 

Completions and Workovers with Hydraulic Fracturing of Oil Wells 

§98.236(g)(10) For each oil well completion or workover and well type combination, the total N2O emissions, in metric tons N2O, 

if the well emissions were vented to a flare. 

Completions and Workovers without Hydraulic Fracturing 

§98.236(h)(1)(i) A list of the well ID numbers for wells associated with each sub-basin that had gas well completions without 

hydraulic fracturing and without flaring. 

Completions and Workovers without Hydraulic Fracturing 

§98.236(h)(2)(i) A list of the well ID numbers for wells associated with each sub-basin that had gas well completions without 

hydraulic fracturing and with flaring. 

Completions and Workovers without Hydraulic Fracturing 

§98.236(h)(3)(i) A list of the well ID numbers for wells associated with each sub-basin that had gas well workovers without 

hydraulic fracturing and without flaring. 

Completions and Workovers without Hydraulic Fracturing 

§98.236(h)(4)(i) A list of the well ID numbers for wells associated with each sub-basin that had gas well workovers without 

hydraulic fracturing and with flaring. 

Blowdown Vent Stacks §98.236(i)(1)(i) If you calculated emissions from blowdown vent stacks by equipment or event type, the total number of 

blowdowns in the calendar year for the equipment or event type (the sum of equation variable “N” from Equation 

W-14A or Equation W-14B of this subpart, for all unique physical volumes for the equipment or event type). 

Blowdown Vent Stacks §98.236(i)(1)(ii) If you calculated emissions from blowdown vent stacks by equipment type, annual CO2 emissions for the 

equipment type, in metric tons CO2, calculated according to § 98.233(i)(2)(iii). 

Blowdown Vent Stacks §98.236(i)(1)(iii) If you calculated emissions from blowdown vent stacks by equipment type, annual CH4 emissions for the 

equipment type, in metric tons CH4, calculated according to §98.233(i)(2)(iii). 
Emission Source Citation Reference Proposed Rule Text 

Blowdown Vent Stacks §98.236(i)(2)(i) If you elect to calculate emissions from blowdown vent stacks by using a flow meter according to §98.233(i)(3), 

annual CO2 emissions from all blowdown vent stacks at the facility for which emissions were calculated using 

flow meters, in metric tons CO2 (the sum of all CO2 mass emission values calculated according to § 98.233(i)(3), 

for all flow meters). 

Blowdown Vent Stacks §98.236(i)(2)(ii) If you elect to calculate emissions from blowdown vent stacks by using a flow meter according to §98.233(i)(3), 

annual CH4 emissions from all blowdown vent stacks at the facility for which emissions were calculated using 

flow meters, in metric tons CH4, (the sum of all CH4 mass emission values calculated according to § 98.233(i)(3), 

for all flow meters). 

Blowdown Vent Stacks §98.236(i)(3)(i) For each separate transmission pipeline blowdown event, annual CO2 emission in metric tons CO2. Blowdown Vent Stacks §98.236(i)(3)(ii) For each separate transmission pipeline blowdown event, annual CH4 emission in metric tons CH4. Blowdown Vent Stacks §98.236(i)(3)(iii) Latitude and longitude location of the blowdown event in decimal degree format. Storage Tanks §98.236(j) Whether your facility sends produced oil to atmospheric tanks. Storage Tanks §98.236(j) If any of the atmospheric tanks are observed to have malfunctioning dump valves, indicate that dump valves were 

malfunctioning. 

Storage Tanks §98.236(j)(1)(i) If using Calculation Method 1 or 2, the sub-basin ID. Storage Tanks §98.236(j)(1)(ii) For the onshore petroleum and natural gas production segment only, if using Calculation Method 1 or 2, a list of 

the well ID number(s) associated with the tanks that controlled emissions with flares. 

Storage Tanks §98.236(j)(1)(iii) For the onshore petroleum and natural gas production industry segment only, if using Calculation Method 1 or 2, a 

list of the well ID number(s) associated with the tanks that did not control emissions with flares. 

Storage Tanks §98.236(j)(1)(iv) If using Calculation Method 1 or 2, calculation method used, and name of the software package used if using 

Calculation Method 1. 

Storage Tanks §98.236(j)(1)(v) If using Calculation Method 1 or 2, the total annual gas-liquid separator oil volume that is sent to applicable 

onshore storage tanks, in barrels. 

Storage Tanks §98.236(j)(1)(vi) If using Calculation Method 1 or 2, the average gas-liquid separator temperature, in degrees Fahrenheit. Storage Tanks §98.236(j)(1)(vii) If using Calculation Method 1 or 2, the average gas-liquid separator pressure, in pounds per square inch gauge. Storage Tanks §98.236(j)(1)(viii) If using Calculation Method 1 or 2, the average sales oil or stabilized oil API gravity, in degrees. Storage Tanks §98.236(j)(1)(ix) If using Calculation Method 1 or 2, the minimum and maximum concentration (mole fraction) of CO2 in flash gas 

from storage tanks. 

Storage Tanks §98.236(j)(1)(x) If using Calculation Method 1 or 2, the minimum and maximum concentration (mole fraction) of CH4 in flash gas 

from storage tanks. 

Storage Tanks §98.236(j)(1)(xi) If using Calculation Method 1 or 2, the number of wells sending oil to gas-liquid separators or directly to 

atmospheric tanks. 

Storage Tanks §98.236(j)(1)(xii) If using Calculation Method 1 or 2, the number of atmospheric tanks. 
Emission Source Citation Reference Proposed Rule Text 

Storage Tanks §98.236(j)(1)(xiv)(A) If using Calculation Method 1 or 2, if any emissions from the atmospheric tanks at your facility were controlled 

with vapor recovery systems, the number of atmospheric tanks that control emissions with vapor recovery systems

Storage Tanks §98.236(j)(1)(xiv)(B) If using Calculation Method 1 or 2, if any emissions from the atmospheric tanks at your facility were controlled 

with vapor recovery systems, the total CO2 mass, in metric tons CO2, that was recovered during the calendar year 

using a vapor recovery system. 

Storage Tanks §98.236(j)(1)(xiv)(C) If using Calculation Method 1 or 2, if any emissions from the atmospheric tanks at your facility were controlled 

with vapor recovery systems, the total CH4 mass, in metric tons CH4, that was recovered during the calendar year 

using a vapor recovery system. 

Storage Tanks §98.236(j)(1)(xiv)(D) If using Calculation Method 1 or 2, if any emissions from the atmospheric tanks at your facility were controlled 

with vapor recovery systems, annual CO2 emissions, in metric tons CO2, from atmospheric tanks equipped with vapor recovery systems. 

Storage Tanks §98.236(j)(1)(xiv)(E) If using Calculation Method 1 or 2, if any emissions from the atmospheric tanks at your facility were controlled 

with vapor recovery systems, annual CH4 emissions, in metric tons CH4, from atmospheric tanks equipped with vapor recovery systems. 

Storage Tanks §98.236(j)(1)(xv)(A) If using Calculation Method 1 or 2, if any atmospheric tanks at your facility vented gas directly to the atmosphere 

without using a vapor recovery system or without flaring, number of atmospheric tanks that vented gas directly to 

the atmosphere without using a vapor recovery system or without flaring. 

Storage Tanks §98.236(j)(1)(xv)(B) If using Calculation Method 1 or 2, if any atmospheric tanks at your facility vented gas directly to the atmosphere 

without using a vapor recovery system or without flaring, annual CO2 emissions, in metric tons CO2, that resulted from venting gas directly to the atmosphere. 

Storage Tanks §98.236(j)(1)(xv)(C) If using Calculation Method 1 or 2, if any atmospheric tanks at your facility vented gas directly to the atmosphere 

without using a vapor recovery system or without flaring, annual CH4 emissions, in metric tons CH4, that resulted from venting gas directly to the atmosphere. 

Storage Tanks §98.236(j)(1)(xvi)(A) If using Calculation Method 1 or 2, if you controlled emissions from any atmospheric tanks at your facility with 

one or more flares, the number of atmospheric tanks that controlled emissions with flares. 

Storage Tanks §98.236(j)(1)(xvi)(B) If using Calculation Method 1 or 2, if you controlled emissions from any atmospheric tanks at your facility with 

one or more flares, annual CO2 emissions, in metric tons CO2, from atmospheric tanks that controlled emissions 

with one or more flares. 

Storage Tanks §98.236(j)(1)(xvi)(C) If using Calculation Method 1 or 2, if you controlled emissions from any atmospheric tanks at your facility with 

one or more flares, annual CH4 emissions, in metric tons CH4, from atmospheric tanks that controlled emissions 

with one or more flares. 

Storage Tanks §98.236(j)(1)(xvi)(D) If using Calculation Method 1 or 2, if you controlled emissions from any atmospheric tanks at your facility with 

one or more flares, annual N2O emissions, in metric tons N2O, from atmospheric tanks that controlled emissions 

with one or more flares. 

Storage Tanks §98.236(j)(2)(i)(A) If using Calculation Method 3, the total annual oil/condensate throughput that is sent to all atmospheric tanks in 

the gathering and boosting facility, in barrels. 
Emission Source Citation Reference Proposed Rule Text 

Storage Tanks §98.236(j)(2)(i)(B) If using Calculation Method 3, an estimate of the fraction of oil/condensate throughput reported in paragraph 

(j)(2)(i)(A) sent to atmospheric tanks in the basin that controlled emissions with flares. 

Storage Tanks §98.236(j)(2)(i)(C) If using Calculation Method 3, an estimate of the fraction of oil/condensate throughput reported in paragraph 

(j)(2)(i)(A) sent to atmospheric tanks in the basin that controlled emissions with vapor recovery systems. 

Storage Tanks §98.236(j)(2)(i)(D) If using Calculation Method 3, the number of atmospheric tanks in the basin. Storage Tanks §98.236(j)(2)(ii)(A) For each sub-basin with atmospheric tanks whose emissions were calculated using Calculation Method 3 and that 

did not control emissions with flares, sub-basin ID. 

Storage Tanks §98.236(j)(2)(ii)(B) If using Calculation Method 3, the number of atmospheric tanks in the sub-basin that did not control emissions 

with flares, including those that have vapor recovery. 

Storage Tanks §98.236(j)(2)(ii)(B) For the onshore petroleum and natural gas production segment only, if using Calculation Method 3, a list of the 

well ID numbers of wells associated with atmospheric tanks in the sub-basin that did not control emissions with 

flares. 

Storage Tanks §98.236(j)(2)(ii)(C) If using Calculation Method 3, annual CO2 emissions, in metric tons CO2, from atmospheric tanks in the subbasin that did not control emissions with flares, calculated using Equation W-15 of this subpart and adjusted for 

vapor recovery, if applicable. 

Storage Tanks §98.236(j)(2)(ii)(D) If using Calculation Method 3, annual CH4 emissions, in metric tons CH4, from atmospheric tanks in the subbasin that vented gas directly to the atmosphere, calculated using Equation W-15 of this subpart and adjusted for 

vapor recovery, if applicable. 

Storage Tanks §98.236(j)(2)(iii)(A) For each sub-basin with atmospheric tanks whose emissions were calculated using Calculation Method 3 and that 

controlled emissions with flares, sub-basin ID. 

Storage Tanks §98.236(j)(2)(iii)(B) If using Calculation Method 3, the number of atmospheric tanks in the sub-basin that controlled emissions with 

flares. 

Storage Tanks §98.236(j)(2)(iii)(B) For the onshore petroleum and natural gas production segment only, if using Calculation Method 3, a list of the 

well ID numbers of wells associated with atmospheric tanks in the sub-basin that controlled emissions with flares. 

Storage Tanks §98.236(j)(2)(iii)(C) If using Calculation Method 3, annual CO2 emissions, in metric tons CO2, from atmospheric tanks that controlled 

emissions with flares, calculated using Equation W-15 of this subpart. 

Storage Tanks §98.236(j)(2)(iii)(D) If using Calculation Method 3, annual CH4 emissions, in metric tons CH4, from atmospheric tanks that controlled 

emissions with flares, calculated using Equation W-15 of this subpart. 

Storage Tanks §98.236(j)(2)(iii)(E) If using Calculation Method 3, annual N2O emissions, in metric tons N2O, from atmospheric tanks that controlled 

emissions with flares. 

Storage Tanks §98.236(j)(3)(i) The total number of gas-liquid separators whose liquid dump valves did not close properly during the calendar 

year 

Storage Tanks §98.236(j)(3)(ii) The total time the dump valves on gas-liquid separators did not close properly in the calendar year, in hours (“Tn” 

in Equation W-16). 
Emission Source Citation Reference Proposed Rule Text 

Storage Tanks §98.236(j)(3)(iii) Annual CO2 emissions, in metric tons CO2, that resulted from dump valves on gas-liquid separators not closing 

properly during the calendar year, calculated using Equation W-16 of this subpart. 

Storage Tanks §98.236(j)(3)(iv) Annual CH4 emissions, in metric tons CH4, that resulted from the dump valves on gas-liquid separators not closing 

properly during the calendar year, calculated using Equation W-16 of this subpart. 

Well Testing Venting and Flaring 

§98.236(l)(1)(ii) If you used Equation W-17A to calculate annual volumetric natural gas emissions at actual conditions from oil 

wells and the emissions are not vented to a flare, well ID numbers for the wells tested in the calendar year. 

Well Testing Venting and Flaring 

§98.236(l)(2)(ii) If you used Equation W-17A to calculate annual volumetric natural gas emissions at actual conditions from oil 

wells and the emissions are vented to a flare, well ID numbers for the wells tested in the calendar year. 

Well Testing Venting and Flaring 

§98.236(l)(3)(ii) If you used Equation W-17B to calculate annual volumetric natural gas emissions at actual conditions from gas 

wells and the emissions were not vented to a flare, well ID numbers for the wells tested in the calendar year. 

Well Testing Venting and Flaring 

§98.236(l)(4)(ii) If you used Equation W-17B to calculate annual volumetric natural gas emissions at actual conditions from gas 

wells and the emissions were vented to a flare, well ID numbers for the wells tested in the calendar year. 

Associated Natural Gas Venting and Flaring 

§98.236(m)(1) A list of well ID numbers for wells in each sub-basin for which associated gas was vented or flared. 

Associated Natural Gas Venting and Flaring 

§98.236(m)(7)(i) A list of well ID numbers for wells for which associated gas was vented directly to the atmosphere without flaring

Associated Natural Gas Venting and Flaring 

§98.236(m)(8)(i) A list of well ID numbers for wells for which associated gas was flared. 

Flare Stacks §98.236(n)(1) Unique name or ID for the flare stack. Flare Stacks §98.236(n)(2) Indicate whether the flare stack has a continuous flow measurement device. Flare Stacks §98.236(n)(3) Indicate whether the flare stack has a continuous gas composition analyzer on feed gas to the flare. Flare Stacks §98.236(n)(4) Volume of gas sent to the flare, in standard cubic feet (“Vs” in Equations W-19 and W-20 of this subpart). Flare Stacks §98.236(n)(5) Fraction of the feed gas sent to an un-lit flare (“Zu” in Equation W-19 of this subpart). Flare Stacks §98.236(n)(6) Flare combustion efficiency, expressed as the fraction of gas combusted by a burning flare. Flare Stacks §98.236(n)(7) Mole fraction of CH4 in the feed gas to the flare (“XCH4” in Equation W-19 of this subpart). Flare Stacks §98.236(n)(8) Mole fraction of CO2 in the feed gas to the flare (“XCO2” in Equation W-20 of this subpart). Flare Stacks §98.236(n)(9) Annual CO2 emissions, in metric tons CO2 (refer to Equation W-20 of this subpart). Flare Stacks §98.236(n)(10) Annual CH4 emissions, in metric tons CH4 (refer to Equation W-19 of this subpart), unless a CEMS was used to 

measure emissions. 

Flare Stacks §98.236(n)(11) Annual N2O emissions, in metric tons N2O (refer to Equation W-40 of this subpart), unless a CEMS was used to 

measure emissions. 

Flare Stacks §98.236(n)(12) Whether a CEMS was used to measure emissions from the flare. 
Emission Source Citation Reference Proposed Rule Text 

Flare Stacks §98.236(n)(13) For the onshore petroleum and natural gas production industry segment only, the well ID number(s) associated 

with each unique name or ID for the flare stack. 

Centrifugal Compressors §98.236(o)(5)(i) Number of centrifugal compressors that have wet seal oil degassing vents. Centrifugal Compressors §98.236(o)(5)(ii) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for the wells at 

which the centrifugal compressors that have wet seal oil degassing vents are located. 

Centrifugal Compressors §98.236(o)(5)(iii) Annual CO2 emissions, in metric tons CO2, from centrifugal compressors with wet seal oil degassing vents Centrifugal Compressors §98.236(o)(5)(iv) Annual CH4 emissions, in metric tons CH4, from centrifugal compressors with wet seal oil degassing vents. Reciprocating Compressors 

§98.236(p)(5)(i) Number of reciprocating compressors. 

Reciprocating Compressors 

§98.236(p)(5)(ii) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for the wells at 

which reciprocating compressors are located. 

Reciprocating Compressors 

§98.236(p)(5)(iii) Annual CO2 emissions, in metric tons CO2, from reciprocating compressors. 

Reciprocating Compressors 

§98.236(p)(5)(iv) Annual CH4 emissions, in metric tons CH4, from reciprocating compressors. 

Equipment Leaks by Population Counts 

§98.236(r)(1)(i) Component type, service type, and geographic location of the emission source type. 

Equipment Leaks by Population Counts 

§98.236(r)(1)(i) For the onshore petroleum and natural gas production segment only, a list of well ID numbers for the associated 

wells. 

Equipment Leaks by Population Counts 

§98.236(r)(1)(ii) Total number of the emission source type at the facility (“Counte” in Equation W-32A of this subpart). 

Equipment Leaks by Population Counts 

§98.236(r)(1)(iii) Average estimated time that the emission source type was operational in the calendar year, in hours (“Te” in 

Equation W-32A of this subpart). 

Equipment Leaks by Population Counts 

§98.236(r)(1)(iv) Annual CO2 emissions, in metric tons CO2, for the component type, service type, and geographic location. 

Equipment Leaks by Population Counts 

§98.236(r)(1)(v) Annual CH4 emissions, in metric tons CH4, for the component type, service type, and geographic location. 

Equipment Leaks by Population Counts 

§98.236(r)(3)(i) Calculation method used for equipment leaks. 

Equipment Leaks by Population Counts 

§98.236(r)(3)(ii)(A) An indication of whether the facility contains the major equipment type in Table W-1B. 

Equipment Leaks by Population Counts 

§98.236(r)(3)(ii)(B) For each major equipment type in natural gas gathering and boosting, and geographic location combination in 

Table W-1B, if the facility does contain the equipment type, the count of the major equipment type. 

EOR Injection Pumps §98.236(w)(2) The well ID number(s) associated with each EOR injection pump. 
Emission Source Citation Reference Proposed Rule Text 

EOR Hydrocarbon Liquids 

§98.236(x)(2) Well ID numbers associated with the EOR operations in each sub-basin. 

Combustion §98.236(z)(1)(i) For external fuel combustion units with a rated heat capacity less than or equal to 5 million Btu per hour or interna

fuel combustion units that are not compressor-drivers, with a rated heat capacity less than or equal to 1 million Btu 

per hour (or the equivalent of 130 horsepower), the type of combustion unit. 

Combustion §98.236(z)(1)(ii) For each combustion unit type listed in §98.236(z)(1), the total number of combustion units. Combustion §98.236(z)(1)(iii) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers associated with 

each combustion unit type listed in §98.236(z)(1). 

Combustion §98.236(z)(2)(i) For external fuel combustion units with a rated heat capacity greater than 5 mmBtu/hr; internal fuel combustion 

units that are not compressor-drivers, with a rated heat capacity greater than 1 million Btu per hour (or the 

equivalent of 130 horsepower); or internal fuel combustion units of any heat capacity that are compressor-drivers, 

the type of combustion unit. 

Combustion §98.236(z)(2)(ii) A list of the well ID numbers associated with the combustion units (for the onshore petroleum and natural gas 

production industry segment only). 

Combustion §98.236(z)(2)(iii) For each combustion unit type listed in §98.236(z)(2), the type of fuel combusted. Combustion §98.236(z)(2)(iv) If your facility contains: external fuel combustion units with a rated heat capacity greater than 5 mmBtu/hr; 

internal fuel combustion units that are not compressor-drivers, with a rated heat capacity greater than 1 million Btu 

per hour (or the equivalent of 130 horsepower); or internal fuel combustion units of any heat capacity that are 

compressor-drivers, report for each combustion unit type and fuel type combination, the quantity of fuel 

combusted in the calendar year, in thousand standard cubic feet, gallons, or tons. 

Combustion §98.236(z)(2)(v) For each combustion unit type listed in §98.236(z)(2), annual CO2 emissions, in metric tons CO2, calculated 

according to §98.233(z)(1) and (z)(2). 

Combustion §98.236(z)(2)(vi) For each combustion unit type listed in §98.236(z)(2), annual CH4 emissions, in metric tons CH4, calculated 

according to §98.233(z)(1) and (z)(2). 

Combustion §98.236(z)(2)(vii) For each combustion unit type listed in §98.236(z)(2), annual N2O emissions, in metric tons N2O, calculated 

according to §98.233(z)(1) and (z)(2). 

General §98.236(aa)(1)(ii)(D) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for producing 

wells at the end of the calendar year. 

General §98.236(aa)(1)(ii)(E) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for wells 

acquired during the calendar year. 

General §98.236(aa)(1)(ii)(F) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for wells 

divested during the calendar year. 

General §98.236(aa)(1)(ii)(G) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for wells 

completed during the calendar year. 
Emission Source Citation Reference Proposed Rule Text 

General §98.236(aa)(1)(ii)(H) For the onshore petroleum and natural gas production segment only, a list of the well ID numbers for wells taken 

out of production during the calendar year. 

General §98.236(aa)(10)(i) The quantity of produced gas throughput in the calendar year, in thousand standard cubic feet. General §98.236(aa)(10)(ii) The quantity of produced gas consumed by the facility in the calendar year, in thousand standard cubic feet. General §98.236(aa)(10)(iii) The quantity of produced condensate throughput in the calendar year, in barrels. General §98.236(aa)(10)(iv) The quantity of produced oil throughput in the calendar year, in barrels. General §98.236(aa)(10)(v) The quantity of gas flared, vented and/or unaccounted for in the calendar year, in thousand standard cubic feet. Natural gas transmission pipelines 

§98.236(aa)(11)(i) The quantity of natural gas received at all custody transfer stations in the calendar year, in thousand standard cubic 

feet. This value may include meter corrections, but only for the calendar year covered by the annual report. 

Natural gas transmission pipelines 

§98.236(aa)(11)(ii) The quantity of natural gas withdrawn from in-system storage in the calendar year, in thousand standard cubic feet

Natural gas transmission pipelines 

§98.236(aa)(11)(iii) The quantity of natural gas added to in-system storage in the calendar year, in thousand standard cubic feet. 

Natural gas transmission pipelines 

§98.236(aa)(11)(iv) The quantity of natural gas transferred to third parties such as LDCs or other transmission pipelines, in thousand 

standard cubic feet. 

Natural gas transmission pipelines 

§98.236(aa)(11)(v) The quantity of natural gas consumed by the transmission pipeline facility for operational purposes, in thousand 

standard cubic feet. 

Natural gas transmission pipelines 

§98.236(aa)(11)(vi) The miles of transmission pipeline in the facility.