Southern Natural Gas Company

Seventh Revised Volume No. 1

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Effective Date: 05/05/2008, Docket: RP04- 42-003, Status: Effective

Fourth Revised Sheet No. 108 Fourth Revised Sheet No. 108 : Effective

Superseding: Third Revised Sheet No. 108



Section 3.1 (continued)

(g) have a cricondentherm hydrocarbon dew point temperature ("HDP") equal

to or less than the specification posted on SoNet Premier as a "Hydrocarbon Dew

Point Limitation" as it becomes necessary from time to time to prevent hydrocarbon

condensation in COMPANY's system or from deliveries to its customers in order to

ensure that the gas redelivered will be merchantable as provided in Section 3.2

below. COMPANY will use certain monitoring points downstream of major gas supply

sources on its system ("Monitoring Points") to measure the quantity of equivalent

gallons of liquid per mcf of gas of Hexanes and heavier (C6+) hydrocarbons in the

gas stream ("GPM Factor"). The Monitoring Points will be located at COMPANY'S

Enterprise Compressor Station on its South Main Line, the Rome No. 1 Meter Station

on COMPANY'S facilities and those of Southern LNG Inc. in Chatham County, Georgia.

The HDP calculations will be performed using the Peng Robinson equations of state.

The Hexane plus values used in the HDP calculation will be verified on an annual

basis using an extended analysis from samples taken at the Monitoring Points.

COMPANY will use the actual GPM Factor at the Monitoring Points or a projected GPM

Factor based on confirmed or reasonably anticipated events, e.g., a processing plant

outage, in order to determine (i) whether a limitation is necessary, and (ii) what

portion of COMPANY's system is affected by an excessive GPM Factor. COMPANY shall

then determine the GPM Factor level that is necessary to ensure that liquefiable

hydrocarbons do not condense out of the gas stream ("GPM Target"). The GPM Target

will then be correlated to an HDP specification which will be included in the

posting ("HDP Specification"). COMPANY shall establish groups of two or more meter

stations that will be sampled at a common point in order to determine whether they

meet the HDP Specification in the aggregate ("Aggregation Group"). All of the

processing plants located on COMPANY's system near Toca, Louisiana, shall be

referred to herein as the "Toca Plant." All of the Receipt Points located upstream

of the Toca Plant shall constitute one such Aggregation Group. The gas supplies from

the Receipt Points in such Aggregation Group will be sampled immediately downstream

of the Toca Plant at a point before the first Receipt Point on COMPANY's facilities

downstream of the Toca Plant. Other Aggregation Groups as established from time-to-

time shall be posted on SoNet Premier. New Receipt Points will be automatically

assigned to the existing Aggregation Group covering the geographical area where the

point is located. COMPANY shall provide thirty (30) days notice with a posting on

SoNet Premier to move a Receipt Point from one Aggregation Group to another and

shall include in said posting the operational reasons for moving the Receipt Point.

COMPANY shall attempt to minimize the use of HDP Limitation Notices and to the

greatest degree possible, shall endeavor to implement the highest HDP for specific

portions of its pipeline system as necessary to prevent hydrocarbon condensation

based on operating conditions, and shall limit the duration of the HDP Limitation

Notice to the extent possible. In assessing system operating conditions, COMPANY

shall consider all relevant factors affecting hydrocarbon condensation, including

specifically (i) the HDP at the Monitoring Point, (ii) events that could lead to

hydrocarbon condensation, (iii) market demand (location and volume), (iv) supply

diversity (location and volume), (v) the weather, and (vi) any opportunities within

Southern's control to blend gas supplies. COMPANY will include in any posting

pursuant to this section (1) the anticipated duration of the limitation; (2) the

Receipt Point(s) and Aggregation Group(s) with their associated Receipt Point(s) on

the system subject to the limitation; (3) the effective date and time by which

parties have to conform to the limitation;(4) the latest available HDP at the

Monitoring Points, all Aggregation Group(s) upstream of the affected Monitoring

Point, all pipeline interconnections upstream of the affected Monitoring Point, and

all Receipt Point(s) that have an HDP above the HDP Specification within the

Aggregation Group(s) that has/have an HDP above the HDP Specification; and (5) the

reason for the limitation, including the information utilized in deciding to issue

the HDP Limitation Notice. Receipt Points delivering gas into COMPANY's system

directly from well head production facilities where the actual flow during the

calendar month immediately preceding the month in which the limitation notice is

posted averaged 500 dth/d or less will be exempt from the limitation in any such

posting. COMPANY will provide prior notice by posting the limitation at least two

(2) days before the limitation will be effective. COMPANY will attempt to provide

this notice prior to the beginning of the month in which the limitation is to be

effective, but if such prior notice is not practicable, COMPANY will explain the

reason in the posting why it was unable to give such notice prior to the beginning

of the month. COMPANY shall accept gas entering the system at all Receipt Points and