Exhibit 10.34

SPECIFIC TERMS IN THIS EXHIBIT HAVE BEEN REDACTED BECAUSE CONFIDENTIAL TREATMENT FOR THOSE TERMS HAS BEEN REQUESTED. THE REDACTED MATERIAL
HAS BEEN SEPERATELY FILED WITH THE SECURITIES AND EXCHANGE COMMISSION, AND THE TERMS HAVE BEEN MARKED AT THE APPROPRIATE PLACE WITH TWO ASTERISKS (**).

|                                                                                                                                                    |  |                                                    
|--------------------------------------------------------------------------------------------------------------------------------------------------- |  | ---------------------------------------------------
|DYNEGY LIQUIDS MARKETING AND TRADE
("DYNEGY")
1000 Louisiana, Suite 5800
Houston, Texas 77002-5050
Telephone: (713) 57-6400
Telecopy: (713)507-3715 |  | DYNEGY
Raw Product Purchase Agreement
("Agreement")

|         |  |                                                              |  |                                                                               |  |                                      |  | 
|-------- |  | ------------------------------------------------------------ |  | ----------------------------------------------------------------------------- |  | ------------------------------------ |  | 
|         |  |                                                              |  |                                                                               |  |                                      |  | 
|Seller:  |  | MarkWest Energy East
Texas Gas Company L.P.
("MarkWest")     |  | Confirming Arrangements Made Between: John MollenkopfMarkWest Representative: |  | Date:February 11, 2005              
|Address: |  | 155 Inverness Drive West,
Suite 200
Englewood, CO 80112-5000 |  | And:                                                                          |  | David PetersonDynegy Represenatative |  | 
|         |  |                                                              |  | Dynegy Contract No.                                                           |  | MarkWest Contract No.               

|   |  |                     |  |                             |  |                                |  |        |  |                                   |  |                     |  |                     |  |                  |  |             
|-- |  | ------------------- |  | --------------------------- |  | ------------------------------ |  | ------ |  | --------------------------------- |  | ------------------- |  | ------------------- |  | ---------------- |  | ------------
|   |  |                     |  |                             |  |                                |  |        |  | Location                          |  |                     |  |                     |  |                 
|2. |  | Product
Description |  | Approx.
Volume
(net @ 60 F) |  | Measurement
Unit Basis
(see 3) |  | Origin |  | Destination                       |  | Del.
Meth.
(see 4)  |  | Price(CentslGallon) |  | FOB             
|   |  |                     |  |                             |  |                                |  |        |  |                                   |  |                     |  |                     |  |                  |  |             
|   |  | NGL Raw Product     |  | ** barrels
per day          |  | Bbl.                           |  | M      |  | MarkWest's
Carthage, TX
Gas Plant |  | Mont
Belvieu,
Texas |  | P                   |  | See
Attachment
A |  | See
Attached

Dynegy
Liquids Marketing and Trade
    1000 Louisiana, Suite 5800
    Houston, Texas 77002-5050

| |  |                                             |  |                                    |  |        |  |                      
| |  | ------------------------------------------- |  | ---------------------------------- |  | ------ |  | ---------------------
| |  | Accepted and Agreed to:                     |  | Accepted and Agreed to:           
| |  |                                             |  |                                    |  |        |  |                      
| |  | MarkWest Energy East Texas Gas Company L.P. |  | Dynegy Liquids Marketing and Trade
| |  | By:                                         |  | /s/ Frank M. Semple                |  | By:    |  | /s/ Bruce Williamson 
| |  | Title:                                      |  | Frank M. Semple, President and CEO |  | Title: |  | Bruce Williamson, CEO

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ATTACHMENT AVOLUMES, PRICING AND SPECIAL TERMS    toRaw Product Purchase Agreement



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| |                   |  |     |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                      
| | ----------------- |  | --- |  | -----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
| | Fractionation Fee |  | =** |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                      
| | Where:            |  |     |  |                                                                                                                                                                                                                                                                                                                                                                                                                                                      
| | Gas Price         |  | =   |  | The**of INSIDE FERC'S GAS MARKET REPORT, for natural gas for the month in which the Fractionation Fee is being computed.                                                                                                                                                                                                                                                                                                                             
| | Elec              |  | =   |  | The combined average cost of purchased electricity, in cents per kilowatt hour, at ** during the preceding month.                                                                                                                                                                                                                                                                                                                                    
| | CPI-U             |  | =   |  | The latest available Consumer Price Index, All Urban Consumers("CPI-U"). U.S. city average, All Items. 1982-84 = 100 (Unadjusted) as published by the United States Bureau of Labor Statistics (the
"BLS") or any successor agency thereto ("CPIIndex"). The CPIU Index shall be taken from the data published by the Bureau of Labor Statistics either electronically at its then current Internet site or as same is published in hardcopy
form.

2

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Wire Transfer Due

For Product Moved On**

**

**




3

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ATTACHMENT BGENERAL TERMS AND CONDITIONS    toRaw Product Purchase Agreement

1.     DEFINITIONS

As used herein, the following terms shall be given the following meanings:



2.     REPRESENTATIONS AND WARRANTIES



3.     WAIVER OF CONSUMER RIGHTS



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4.     DELIVERY



5.     QUANTITY



6.     PASSAGE OF TITLE



7.     MEASUREMENT



8.     CLAIMS



2

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9.     QUALITY AND TESTING



10.   OFFSPEC RP



11.   INSPECTION



12.   FORCE MAJEURE



3

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4

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13.   INDEMNITIES



5

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14.   ASSIGNMENT



15.   NOTICE



16.   AUDIT



17.   TAXES



6

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18.   LIMITATION OF LIABILITY



19.   CONFLICTS OF INTEREST



20.   CONDUCT OF PARTIES' BUSINESS



21.   GOVERNING LAW



22.   CONFIDENTIALITY



23.   SEVERABILITY



7

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24.   NO THIRD PARTY BENEFICIARY



25.   WAIVER



26.   ALTERATIONS



27.   DEFAULT



8

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28.   PRINCIPLES OF CONSTRUCTION AND INTERPRETATION.



9

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