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**Subpart DD —**  **Electrical Transmission and Distribution Equipment Use** 
(a) The electrical transmission and distribution equipment use source category consists of all electric transmission and distribution equipment and servicing inventory insulated with or containing sulfur hexafluoride ( SF § 98.300 Definition of the source category.

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(1) Gas

- insulated substations. ) or perfluorocarbons (PFCs) used within an electric power system. Electric transmission and distribution equipmen t and servicing inventory includes, but is not limited to:

(2) Circuit breakers. (3) Switchgear, including closed

- pressure and hermetically sealed

- pressure switchgear and gas

- insulated lines containing SF 6

(4) Gas co ntainers such as pressurized cylinders. or PFCs.

(5) Gas carts. (6) Electric power transformers. (7) Other containers of SF 6 or PFC.

(a) You must report GHG emissions from an electric power system if the total nameplate capacity of SF § 98.301 Reporting threshold.

6 and PFC containing equipment (excluding hermetically sealed

- pressure equipment) located within the facility, when added to the total nameplatePage 2 of 9 capacity of SF 6

(b) A facility other than an electric power system that is subject to this part because of emissions from any ot her source category listed in Table A

– 3 or A

– 4 in subpart A of this part is not required to report emissions under subpart DD of this part unless the total nameplate capacity of SF and PFC containing equipment (excluding hermetically sealed

- pressure equipment) that is not loca ted within the facility but is under common ownership or control, exceeds 17,820 pounds and the facility meets the requirements of §98.2(a)(1).

6 and PFC containing equipment located within that facility exceeds 17,820 p ounds.

You must report total SF § 98.302 GHGs to report.

6 and PFC emissions from your facility (including emissions from fugitive equipment leaks, installation, servicing, equipment decommissioning and disposal, and from storage cylinders) resulting from t he transmission and distribution servicing inventory and equipment listed in §98.300(a). For acquisitions of equipment containing or insulated with SF 6 or PFCs, you must report emissions from the equipment after the title to the equipment is transferred to the electric power transmission or distribution entity.

(a) Calculate the annual SF § 98.303 Calculating GHG emissions.

6 and PFC emissions using the

mass - balance approach in Equation DD

– 1 of this section:Page 3 of 9

(Eq. DD

- 1) Where:
Decrease in SF 6 Inventory = (pounds of SF 6 stored in containers, but not in energized equipment, at the beginning of the year)

— (pounds of SF 6
Acquisitions of SF stored in containers, but not in energized equipment, at the end of the year).

6 = (pounds of SF 6 purchased from chemical p roducers or distributors in bulk) + (pounds of SF 6 purchased from equipment manufacturers or distributors with or inside equipment, including hermetically sealed

- pressure switchgear) + (pounds of SF 6 Disbursements of SF returned to facility after off

- site recycling).

6 = (pounds of SF 6 in bulk and contained in equipment that is sold to other entities) + (pounds of SF 6 returned to suppliers) + (pounds of SF 6 sent off site for recycling) + (pounds of SF 6 Net Increase in Total Nameplate Capacity of Equipment Operated

= (The Nameplate Capacity of new equipment in pounds, including hermetically sealed

- pressure switchgear)

— (Nameplate Capacity of retiring equipment in pounds, including hermetically sealed

- pressure switchgear) . (Note that Nameplate Capacity refers to the full and proper charge of equipment rather than to the actual charge, which may reflect leakage). sent off

- site for destruction).

(b) Use Equation DD

– 1 of this section to estimate emissions of PFCs from power transformers, substituting the re levant PFC(s) for SF 6 in the equation. § 98.304 Monitoring and QA/QC requirements.Page 4 of 9 (a) For calendar year 2011 monitoring, you may follow the provisions of §98.3(d)(1) through (d)(2) for best available monitoring methods rather than follow the monitoring

re quirements of this section. For purposes of this subpart, any reference in §98.3(d)(1) through (d)(2) to 2010 means 2011, to March 31 means June 30, and to April 1 means July 1. Any reference to the effective date in §98.3(d)(1) through (d)(2)

means Februa ry 28, 2011. (b) You must adhere to the following QA/QC methods for reviewing the completeness and accuracy of reporting: (1) Review inputs to Equation DD

– 1 of this section to ensure inputs and outputs to the company's system are included. (2) Do not enter negative inputs and confirm that negative emissions are not calculated. However, the Decrease in SF 6

(3) Ensure that beginning

- of

- year inventory matches end

- of

year inventory from the previous year. Inventory and the Net Increase in Total Nameplate Capacity may be calculated as negative numbers.

(4) Ensure that in addition to SF 6 purchased from bulk gas distributors, SF 6 purchased from Original Equipment Manufacturers (OEM) and SF 6

(c) Ensure the following QA/QC methods are employed throughout the year: returned to the facility from off

- site recycling are also accounted for amo ng the total additions.Page 5 of 9 (1) Ensure that cylinders returned to the gas supplier are consistently weighed on a scale that is certified to be accurate and precise to within 2 pounds of t he scale's capacity true weight and is periodically recalibrated per the manufacturer's specifications. Either measure residual gas (the amount of gas remaining in returned cylinders) or have the gas supplier measure it. If the gas supplier weighs the resid ual gas, obtain from the gas supplier a detailed monthly accounting, within ± 2 pounds, of residual gas amounts in the cylinders returned to the gas supplier. (2) Ensure that cylinders weighed for the beginning and end of year inventory measurements are we ighed on a scale that is certified to be accurate and precise to within 2 pounds of the scale's capacity true weight and is periodically recalibrated per the manufacturer's specifications. All scales used to measure quantities that are to be reported under §98.306 must be calibrated using calibration procedures specified by the scale manufacturer. Calibration must be performed prior to the first reporting year. After the initial calibration, recalibration must be performed at the minimum frequency specified by the manufacturer. (3) Ensure all substations have provided information to the manager compiling the emissions report (if it is not already handled through an electronic inventory system).Page 6 of 9 (d) GHG Monitoring Plans, as described in §98.3(g)(5), must be co mpleted by April 1, 2011.

A complete record of all measured parameters used in the GHG emissions calculations is required. Replace missing data, if needed, based on data from equipment with a similar namepla te capacity for SF § 98.305 Procedures for estimating missing data.

6 and PFC, and from similar equipment repair, replacement, and maintenance operations.

In addition to the information required by §98.3(c), each annual report must contain the following information for each electric power system, by chemical: § 98.306 Data reporting requirements.

(a) Nameplate capacity of equipment (pounds) containing SF 6

(1) Existing at the beginning of the year (excluding hermetically sealed

- pressure swi tchgear). and nameplate capacity of equipment (pounds) containing each PFC:

(2) New during the year (all SF 6

(3) Retired during the year (all SF - insulated equipment, including hermetically sealed

- pressure switchgear).

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(b) Transmission miles (leng th of lines carrying voltages above 35 kilovolt). - insulated equipment, including hermetically sealed

- pressure switchgear).Page 7 of 9 (c) Distribution miles (length of lines carrying voltages at or below 35 kilovolt). (d) Pounds of SF 6

(e) Pounds o f SF and PFC stored in containers, but not in energized equipment, at the beginning of the year.

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(f) Pounds of SF and PFC stored in containers, but not in energized equipment, at the end of the year.

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(g) Pounds of SF and PFC purchased in bulk from chemical producers or distributors.

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(h) Pounds of SF and PFC purchased from equipment manufacturers or distributor s with or inside equipment, including hermetically sealed

- pressure switchgear.

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(i) Pounds of SF and PFC returned to facility after off

site recycling.

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(j) Pounds of SF and PFC in bulk and contained in equipment sold to other entities.

6 (k) Pounds of SF a nd PFC returned to suppliers.

6 (l) Pounds of SF and PFC sent off

- site for recycling.

6 and PFC sent off

- site for destruction.

In addition to the information required by §98.3(g), you must retain recor ds of the information reported and listed in §98.306. § 98.307 Records that must be retained.

§ 98.308 Definitions.Page 8 of 9 Except as specified in this section, all terms used in this subpart have the same meaning given in the Clean Air Act and subpart A of this part. Facility , with respect to an electr ic power system, means the electric power system as defined in this paragraph. An electric power system is comprised of all electric transmission and distribution equipment insulated with or containing SF 6 or PFCs that is linked through electric power tran smission or distribution lines and functions as an integrated unit, that is owned, serviced, or maintained by a single electric power transmission or distribution entity (or multiple entities with a common owner), and that is located between: (1) The point (s) at which electric energy is obtained from an electricity generating unit or a different electric power transmission or distribution entity that does not have a common owner, and (2) the point(s) at which any customer or another electric power transmiss ion or distribution entity that does not have a common owner receives the electric energy. The facility also includes servicing inventory for such equipment that contains SF 6 or PFCs. Electric power transmission or distribution entity means any entity that transmits, distributes, or supplies electricity to a consumer or other user, including any company, electric cooperative, public electric supply corporation, a similar Federal department (including the Bureau of Reclamation or thePage 9 of 9 Corps of Engineers), a m unicipally owned electric department offering service to the public, an electric public utility district, or a jointly owned electric supply project. Operator , for the purposes of this subpart, means any person who operates or supervises a facility, exclud ing a person whose sole responsibility is to ensure reliability, balance load or otherwise address electricity flow.