EXHIBIT 99.1
                                  PRESS RELEASE


RIO VISTA ENERGY PARTNERS RETAINS TRC COMPANIES, INC. TO CONSIDER STRATEGIC
ALTERNATIVES

HOUSTON--Nov. 10, 2004--Rio Vista Energy Partners L.P. (NASDAQ: RVEP), an energy
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services limited partnership, announced today that it has retained TRC
Companies, Inc. (NYSE: TRR) to assist it in considering strategic alternatives.
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In its role, TRC will help source and structure potential acquisitions and
merger opportunities designed to grow the asset base of the partnership.

"We believe that our partnership structure is an excellent vehicle to acquire
other qualified oil and gas assets," said Richard Shore Jr., Rio Vista Energy's
President. "We feel that TRC is well positioned to help us reach our goal of
replicating the successes of many of the other publicly-traded Master Limited
Partnerships."

About Rio Vista Energy Partners L.P.

Rio Vista Energy Partners is an energy services Master Limited Partnership that
owns or operates Liquefied Petroleum Gas (LPG) assets in Southeast Texas and
Northeastern Mexico. The partnership seeks to grow through the acquisition of
qualified oil and gas assets.

About TRC

Named one of FORTUNE Magazine's 100 Fastest Growing Companies in 2003, Forbes
Top 200 Best Small Companies and Business Week's Top 100 Hot Growth Companies,
TRC is a customer-focused company that creates and implements sophisticated and
innovative solutions to the challenges facing America's environmental,
infrastructure, power, and transportation markets. The Company is also a leading
provider of technical, financial, risk management, and construction services to
both industry and government customers across the country. For more information,
visit TRC's website at www.TRCsolutions.com.
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Forward-Looking Statements

Certain of the statements in this news release are forward-looking statements,
including statements regarding potential strategic alternatives, acquisitions
and merger opportunities and future growth of Rio Vista Energy Partners L.P.
(the "Partnership"). Although these statements reflect the Partnership's
beliefs, they are subject to uncertainties and risks that could cause actual
results to differ materially from expectations. These risks include the fact
that there is no assurance that the Partnership will be able to complete any
strategic transactions, acquisitions or mergers. Even if completed, future
acquisitions and expansions may not be successful, may substantially increase
our indebtedness and contingent liabilities, and may create integration
difficulties. If we do not have sufficient capital resources for acquisitions or
opportunities for expansion, our growth will be limited. All of our assets are
pledged as collateral for existing debt of Penn Octane, and we therefore may be
unable to obtain additional financing collateralized by such assets our ability
to complete future acquisitions and expansions may not be successful. Additional
information regarding risks affecting our business may be found in our
registration statement on Form 10 and Penn Octane's reports on Form 10-Q and
10-K filed with the Securities and Exchange Commission.


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Contact:
     Rio Vista Energy Partners L.P.
     Richard Shore / Ian T. Bothwell, 760-772-9080
     or
     CEOcast, Inc. for Rio Vista Energy Partners L.P.
     Ed Lewis, 212-732-4300



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