Atlas America Announces Atlas Pipeline Partners to Acquire 75% Interest in the NOARK Pipeline System for $163 Million.

PHILADELPHIA -- Atlas America, Inc. (Nasdaq:ATLS) (the "Company") announces that Atlas Pipeline Partners, L.P. (NYSE:APL) (the "Partnership"), of which it is the general partner and a holder of 17% of the Partnership's common units, has entered into an agreement with a subsidiary of OGE Energy Corp. (NYSE:OGE) to acquire a subsidiary which owns a 75% operating interest in NOARK Pipeline System, L.P. ("NOARK"). NOARK's assets, which will be included within the Partnership's Mid-Continent operations, include a FERC regulated interstate pipeline and an unregulated natural gas gathering system. Total consideration will be $163 million, subject to working capital adjustments. Consummation of the acquisition, expected to occur in the fourth quarter of 2005, is subject to approval under the Hart-Scott Rodino Act and other customary closing conditions.

The Partnership expects this acquisition to be immediately accretive to distributable cash flow upon closing of the transaction and to provide additional significant fixed fee revenues, with substantially all of NOARK's gross profit generated from fixed fee arrangements. The Partnership expects the acquisition to generate $15 million to $18 million of cash flow in 2006, and to increase distributions to limited partners, including the Company, by $0.10 to $0.20 in 2006.

In addition, upon completion of the acquisition, the Company anticipates an increase in the distributions it will receive, including incentive distributions, as a result of its ownership of the general partner of the Partnership.

NOARK, through its 100% ownership of Ozark Gas Transmission, L.L.C. ("OGT"), operates 565 miles of FERC regulated interstate pipeline, extending from eastern Oklahoma through central and northeastern Arkansas and into Missouri. OGT has throughput capacity of approximately 322,000 dth/d. OGT currently transports approximately 202,200 dth/d. In addition, NOARK, through its 100% ownership of Ozark Gas Gathering, L.L.C. ("OGG"), operates 365 miles of unregulated gathering pipeline in Oklahoma and Arkansas. OGG provides access to natural gas basins through approximately 400 receipt points that are then transported through OGT. OGG currently gathers approximately 36,400 mcf/d.

Edward E. Cohen, Chairman and C.E.O. of the Company, stated, "We are very excited by the opportunity for Atlas Pipeline to acquire this interest in NOARK - continuing to execute its strategy to build its presence in the mid-continent area by expanding into the long-haul pipeline business and adding to its already extensive gas gathering business. The impact to Atlas America will be considerable through increased distributions to the 1.64 million common units that the Company continues to hold and through additional incentive distributions to the Partnership's general partner - a wholly owned subsidiary of the Company."

The Partnership will host a conference call to discuss the acquisition on Thursday, September 22, 2005 at 10:00 a.m. All interested parties can access the live webcast from the home page of the Atlas Pipeline Partners, L.P. website at www.atlaspipelinepartners.com. For those who cannot listen to the live broadcast, the replay of the webcast will be available following the live call on the website and telephonically starting at noon eastern time on September 22, 2005 until midnight on October 22, 2005 by dialing 888-286-8010 and using the passcode 50103047.

Atlas America, Inc. is an energy company engaged primarily in the development and production of natural gas in the Appalachian Basin for its own account and for its investors through the offering of tax advantaged investment programs. Atlas America also owns 100% of the general partner of Atlas Pipeline Partners, L.P. (NYSE:APL). APL owns and operates more than 3,600 miles of natural gas gathering pipelines in Oklahoma, Texas, Pennsylvania, New York and Ohio and gas processing facilities in Oklahoma. For more information, please visit our website at www.atlasamerica.com, or contact investor relations at [e-mail].

Certain matters discussed within this press release are forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Although Atlas America, Inc. believes the expectations reflected in such forward-looking statements are based on reasonable assumptions, it can give no assurance that its expectations will be attained. The Partnership's actual results, performance or achievements could differ materially from those expressed or implied in this release. NOARK and its subsidiaries are subject to the risks typically associated with natural gas pipelines, including risks associated with replacing natural gas production declines of wells currently connected to its pipelines with new wells, its ability to expand its pipelines, adverse climatic conditions, adverse changes in the price of natural gas and increased costs of supplies and services. The Company discusses these risks in its Annual Report on Form 10-K. In addition, NOARK and its subsidiaries are subject to additional risks including the possibility that production from wells connected to its pipelines will be less than projected, that natural gas transported through NOARK's pipelines from outside sources will be less than projected, that regulatory challenges to its pipeline transportation rates could be brought which could lead to reductions in rates or requirements to make reparation or refund payments, that new regulatory requirements relating to pipeline integrity or safety would require substantial capital or other expenditures, or that other regulatory policy changes could occur that would lead to increased costs or reduced transportation rates. Moreover, the Partnership may encounter difficulties in integrating NOARK into its operations since, if the acquisition is completed, it would be the Partnership's third major acquisition in less than two years and since the Partnership has no prior experience in operating a pipeline regulated by FERC. As a result, the Partnership may not realize anticipated operating advantages or cost savings, may have difficulty in integrating NOARK's operating and reporting systems with the Partnership's existing systems and may not be able to maintain operating efficiencies. The occurrence of any of the foregoing risks could reduce the Partnership's revenues, cash flows and ability to make distributions, including limited and general partner distributions and general partner incentive distributions to the Company.