Southwest Gas : 2023 AGA Template

All methane leak sources per 98.232 (i) (1-6) are included

for distribution. Combustion sources are excluded. CO2

is excluded.

Methane emissions and mitigation from

distribution mains

Number of gas distribution customers

1,927,107

2,051,492

2,093,590

2,157,492

2,195,856

Distribution mains in service

These metrics should include all local distribution

companies (LDCs) held by the Parent Company that

are above the LDC Facility reporting threshold for EPA's

40 C.F.R. 98, Subpart W reporting rule.

Plastic (miles)

23,973

25,473.42

25,974.9

26,423.1

27,315.4

Cathodically protected steel - bare

6,699

6,371.3

6,312.1

6,272.1

6,364.1

and coated (miles)

Unprotected steel - bare and coated (miles)

0

0

0

0

0

Cast iron/wrought iron - without upgrades (miles)

0

0

0

0

0

Plan/commitment to replace/upgrade remaining

These metrics should provide the number of years

miles of distribution mains (# of years to complete)

remaining to take out of service, replace or upgrade

cathodically unprotected steel mains, and cast iron/

wrought iron mains, consistent with applicable state

utility commission authorizations.

Unprotected steel - bare and coated (# of years

0

0

0

0

0

Optional: # of years by pipe type

to complete)

Cast iron/wrought iron (# of years to complete)

0

0

0

0

0

Optional: # of years by pipe type

CO2e fugitive methane emissions from gas

142,959

149,332.5

151,451.5

153,392.5

158,107.5

Fugitive methane emissions (not CO2 combustion

distribution operations (metric tons)

emissions) stated as CO2e, as reported to EPA under

40 CFR 98, Subpart W, sections 98.236(q)(3)(ix)

(D), 98.236(r)(1)(v), and 98.236(r)(2)(v)(B) - i.e., this is

Subpart W methane emissions as input in row 2.2

below and converted to CO2e here. This metric should

include fugitive methane emissions above the reporting

threshold for all natural gas local distribution companies

(LDCs) held by the Parent Company that are above the

LDC Facility reporting threshold for EPA's 40 C.F.R. 98,

Subpart W reporting rule. Calculated value based on

MT CH4 input in row 2.2 (below).

CH4 fugitive methane emissions from gas

5,718

5,973.5

6,058.06

6,135.7

6,324.3

INPUT VALUE (total MT CH4) as explained in definition

distribution operations (metric tons)

above. Subpart W input is CH4 (MT).

CH4 fugitive methane emissions from gas

297.8125

311.1094

315.524

319.5677

329.3906

distribution operations (MMscf/year)

Annual natural gas throughput from gas distribution

205,402,775

230,916,156

219,121,714

216,913,433

229,215,433

This metric provides gas throughput from distribution

operations in thousands of standard cubic feet

(quantity of natural gas delivered to end users) reported

(Mscf/year)

under Subpart W, 40 C.F.R. 98.236(aa)(9)(iv), as reported

on the Subpart W e-GRRT integrated reporting form in

the "Facility Overview" worksheet Excel form, Quantity of

natural gas delivered to end users (column 4).

Annual methane gas throughput from gas

195,132.6

219,370.3

208,165.6

206,067.8

217,754.7

distribution operations in millions of standard cubic

feet (MMscf/year)

Fugitive methane emissions rate (percent MMscf of

0.15%

0.14%

0.15%

0.16%

0.15%

Calculated annual metric (MMscf methane emissions/

methane emissions per MMscf of methane

MMscf methane throughput)

throughput)