Dominion Cove Point LNG, LP

Original Volume No. 1

Effective Date: 08/18/2003, Docket: RP01-217-003, Status: Effective

First Revised Sheet No. 234 First Revised Sheet No. 234 : Effective

Superseding: Original Sheet No. 234

GENERAL TERMS AND CONDITIONS

(Continued)

8. NATURAL GAS QUALITY (Continued)

(j) (v) Calculation of Interchangeability Indexes

a. The following table, titled Table of Interchangeability Calculation Constants, lists the gas components and associated constants

considered in the following interchangeability calculations.

TABLE OF INTERCHANGEABILITY CALCULATION CONSTANTS

Ideal, Gross Number

Heating Value Carbon

at Flame Stoichio- Number of Atoms

Chemical Molecular 14.696 psia Speed metric Hydrogen in Each

Entry Component Symbol Weight in Btu/CF Constant Constant Atoms Hydrocarbon

i x for x MW(i) HHV(i) FS(i) ST(i) H(i) C(i)

----- --------------- -------- --------- ----------- -------- -------- --------- ----------

1 Methane CH4 16.0430 1010.0 148 2.0 4 1

2 Ethane C2H6 30.0700 1769.7 301 3.5 6 2

3 Propane C3H8 44.0970 2516.2 398 5.0 8 3

4 iso-Butane iC4H10 58.1230 3251.9 513 6.5 10 4

5 n-Butane nC4H10 58.1230 3262.4 513 6.5 10 4

6 iso-Pentane iC5H12 72.1500 4000.9 630 8.0 12 5

7 n-Pentane nC5H12 72.1500 4008.7 630 8.0 12 5

8 Nitrogen N2 28.0134 0.0 0 0.0 0 0

9 Oxygen O2 31.9988 0.0 0 (1.0) 0 0

10 Carbon Dioxide CO2 44.0100 0.0 0 0.0 0 0

1. The listed constants are for use in the following interchangeability calculations only. The listed constants are not referenced

in any other section of the tariff.

2. The chemical composition of gas will be determined using accepted industry standards and procedures for chromatographic analyses.

3. Only the listed components are considered in the following interchangeability calculations. Any hydrocarbon compounds other than

those listed shall be assumed to be Pentane and allocated equally between i-Pentane and n-Pentane.

4. Chemical composition will be expressed in mole fractions of each component, x(i). The sum of the mole fractions of all listed

components will be one.