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<TITLE>Rio Vista Energy Partners L.P.</TITLE>
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<H5 align="left" style="page-break-before:always"><A HREF="#toc">Table of Contents</A></H5><P>
<DIV style="font-family: 'Times New Roman',Times,serif">


<DIV align="center" style="font-size: 10pt; margin-top: 6pt"><B>As filed with the Securities and Exchange Commission on February&nbsp;14, 2008</B>
</DIV>


<DIV align="right" style="font-size: 10pt; margin-top: 0pt"><B>Registration No.&nbsp;333-</B>
</DIV>


<DIV style="width: 100%; border-bottom: 2pt solid black; font-size: 1pt">&nbsp;</DIV>
<DIV style="width: 100%; border-bottom: 1pt solid black; font-size: 1pt">&nbsp;</DIV>




<DIV align="center" style="font-size: 14pt; margin-top: 6pt"><B>UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION</B>
</DIV>

<DIV align="center" style="font-size: 12pt"><B>Washington, D.C. 20549</B>
</DIV>

<DIV align="center" style="font-size: 18pt; margin-top: 8pt"><B>FORM S-8</B>
</DIV>


<DIV align="center" style="font-size: 12pt; margin-top: 0pt"><B>REGISTRATION STATEMENT<BR>
UNDER<BR>
THE SECURITIES ACT OF 1933</B>
</DIV>

<DIV align="center" style="font-size: 24pt; margin-top: 8pt"><B>Rio Vista Energy Partners L.P.</B>
</DIV>

<DIV align="center" style="font-size: 10pt">(Exact name of registrant as specified in its charter)</DIV>


<DIV align="center">
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<TR valign="bottom">
    <TD align="center" valign="top"><B>Delaware</B>
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top"><B>20-0153267</B></TD>
</TR>
<TR valign="bottom">
    <TD align="center" valign="top">(State or other jurisdiction
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">(I.R.S. Employer</TD>
</TR>
<TR valign="bottom">
    <TD align="center" valign="top">of incorporation or organization)
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">Identification No.)</TD>
</TR>
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</TABLE>
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
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    <TD width="47%">&nbsp;</TD>
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<TR valign="bottom">
    <TD align="center" valign="top"><B>1313 Alton Gloor Blvd., Suite&nbsp;J</B></TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD align="center" valign="top"><B>Brownsville, Texas</B>
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top"><B>98526</B></TD>
</TR>
<TR valign="bottom">
    <TD align="center" valign="top">(Address of Principal Executive Offices)
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">(Zip Code)</TD>
</TR>
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</TABLE>
</DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><B>Rio Vista Energy Partners L.P. 2005 Equity Incentive Plan</B><BR>
(Full title of the plan)</DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><B>Ian T. Bothwell<BR>
Acting Chief Executive Officer<BR>
Rio Vista Energy Partners L.P.<BR>
1313 Alton Gloor Blvd., Suite&nbsp;J<BR>
Brownsville, Texas 98526</B><BR>
(Name and address of agent for service)</DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><B>(956)&nbsp;831-0886</B><BR>
(Telephone number, including area code, of agent for service)</DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><DIV align="center"><DIV style="font-size: 3pt; margin-top: 16pt; width: 26%; border-top: 1px solid #000000">&nbsp;</DIV></DIV></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><B><I>Copies to:</I></B><BR>
<B>Roy E. Bertolatus<BR>
Andrews Kurth LLP<BR>
600 Travis, Suite&nbsp;4200<BR>
Houston, Texas 77002<BR>
(713)&nbsp;220-4200</B></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><DIV align="center"><DIV style="font-size: 3pt; margin-top: 16pt; width: 26%; border-top: 1px solid #000000">&nbsp;</DIV></DIV></DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or
a smaller reporting company. See the definitions of &#147;large accelerated filer,&#148; &#147;accelerated filer&#148; and &#147;smaller reporting company&#148; in Rule
12b-2 of the Exchange Act. (Check one):
</DIV>
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    <TD width="22%"></TD>
    <TD width="3%"></TD>
    <TD width="22%"></TD>
</TR>
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<TR valign="bottom">
    <TD align="left" valign="top">Large accelerated filer <FONT face="Wingdings">&#111;</FONT>
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">Accelerated filer <FONT face="Wingdings">&#111;</FONT>
</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">Non-accelerated filer <FONT face="Wingdings">&#111;</FONT>
</TD>
    <TD>&nbsp;</TD>
    <TD align="right" valign="top">Smaller reporting company <FONT face="Wingdings">&#120;</FONT></TD>
</TR>
<TR valign="bottom">
    <TD align="left" valign="top">&nbsp;
</TD>
    <TD>&nbsp;</TD>
    <TD colspan="5" align="center" valign="top">(Do not check if a smaller reporting company)</TD>
</TR>
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</TABLE>
</DIV>


<DIV align="center" style="font-size: 10pt; margin-top: 8pt"><B>CALCULATION OF REGISTRATION FEE</B>
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
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<TR style="font-size: 6pt" valign="bottom">
    <TD width="1%">&nbsp;</TD>
    <TD width="54%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD><!-- VRule -->
    <TD width="2%">&nbsp;</TD>
    <TD width="7%">&nbsp;</TD>
    <TD width="2%">&nbsp;</TD><!-- VRule -->
    <TD width="2%">&nbsp;</TD>
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    <TD width="2%">&nbsp;</TD>
    <TD width="7%">&nbsp;</TD>

    <TD width="1%">&nbsp;</TD>
</TR><TR style="font-size: 1px" valign="bottom">
    <TD nowrap align="left" colspan="15" style="border-bottom: 3px double #000000">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">    <TD width="1%">&nbsp;</TD>

    <TD>&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center">&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>Proposed</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>&nbsp;</B></TD>
    <TD width="1%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">    <TD width="1%">&nbsp;</TD>

    <TD>&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center">&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>maximum</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
</TR>

<TR style="font-size: 8pt" valign="bottom">    <TD width="1%">&nbsp;</TD>

    <TD>&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>Proposed maximum</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>aggregate</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>Amount of</B></TD>
    <TD width="1%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">    <TD width="1%">&nbsp;</TD>

    <TD nowrap align="center"><B>Title of securities</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>Amount to be</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>offering price</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>offering</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>registration</B></TD>
    <TD width="1%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">    <TD width="1%">&nbsp;</TD>

    <TD nowrap align="center"><B>to be registered</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>registered (1)(2)</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>per share (3)</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>price</B></TD>
    <TD style="border-right: 2px solid #000000">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center"><B>fee</B></TD>
    <TD width="1%">&nbsp;</TD>
</TR>

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    <TD width="1%" style="border-top: 2px solid #000000">&nbsp;</TD>

<TD style="border-top: 2px solid #000000"><DIV style="margin-left:30px; text-indent:-15px">Common units representing limited partner interests</DIV></TD>
    <TD style="border-right: 2px solid #000000; border-top: 2px solid #000000">&nbsp;</TD>
    <TD style="border-top: 2px solid #000000">&nbsp;</TD>
    <TD nowrap align="center" valign="top" style="border-top: 2px solid #000000">750,000 common units</TD>
    <TD style="border-right: 2px solid #000000; border-top: 2px solid #000000">&nbsp;</TD>
    <TD style="border-top: 2px solid #000000">&nbsp;</TD>
    <TD align="center" valign="top" style="border-top: 2px solid #000000">$14.42</TD>
    <TD style="border-right: 2px solid #000000; border-top: 2px solid #000000">&nbsp;</TD>
    <TD style="border-top: 2px solid #000000">&nbsp;</TD>
    <TD align="center" valign="top" style="border-top: 2px solid #000000">$10,815,000.00</TD>
    <TD style="border-right: 2px solid #000000; border-top: 2px solid #000000">&nbsp;</TD>
    <TD style="border-top: 2px solid #000000">&nbsp;</TD>
    <TD align="center" valign="top" style="border-top: 2px solid #000000">$425.03</TD>
    <TD width="1%" style="border-top: 2px solid #000000">&nbsp;</TD>
</TR>
<TR style="font-size: 1px" valign="bottom">
    <TD nowrap align="left" colspan="15" style="border-top: 3px double #000000">&nbsp;</TD>
</TR>

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</TABLE>
</DIV>

<DIV style="margin-top: 6pt">
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="3%" nowrap align="left">(1)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Pursuant to Rule 416(a) under the Securities Act, there is also being registered such
additional number of common units that become available under the plan because of events such
as recapitalizations, stock dividends, stock splits or similar transactions effected without
the receipt of consideration that increases the number of outstanding common units.</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="3%" nowrap align="left">(2)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Represents common units reserved for issuance under the Rio Vista Energy Partners L.P. 2005
Equity Incentive Plan.</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="3%" nowrap align="left">(3)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>Estimated solely for the purpose of determining the amount of the registration fee in
accordance with Rule 457(c) and (h)&nbsp;under the Securities Act of 1933, as amended, and based on
the average of the high and low prices of the common units as reported by the NASDAQ Global
Market on February&nbsp;7, 2008.</TD>
</TR>

</TABLE>
</DIV>

<DIV style="width: 100%; border-bottom: 1pt solid black; margin-top: 10pt; font-size: 1pt">&nbsp;</DIV>
<DIV style="width: 100%; border-bottom: 2pt solid black; font-size: 1pt">&nbsp;</DIV>

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<TR><TD colspan="9"><A HREF="#000">PART I INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS</A></TD></TR>
<TR><TD colspan="9"><A HREF="#001">PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</A></TD></TR>
<TR><TD colspan="9"><A HREF="#002">SIGNATURES</A></TD></TR>
<TR><TD colspan="9"><A HREF="#003">POWER OF ATTORNEY</A></TD></TR>
<TR><TD colspan="9"><A HREF="#004">EXHIBIT INDEX</A></TD></TR>
<TR><TD colspan="9"><A HREF="v38126exv5w1.htm">EXHIBIT 5.1</A></TD></TR>
<TR><TD colspan="9"><A HREF="v38126exv23w1.htm">EXHIBIT 23.1</A></TD></TR>
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<DIV align="left"><A NAME="000"></A></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>PART I</B>
</DIV>



<DIV align="center" style="font-size: 10pt; margin-top: 6pt"><B>INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The document(s) containing the information specified in Part&nbsp;I of Form S-8 (plan information
and registrant information) will be sent or given to employees as specified by Rule&nbsp;428(b)(1) under
the Securities Act of 1933, as amended (the &#147;Securities Act&#148;). In accordance with Rule&nbsp;428 and the
requirements of Part&nbsp;I of Form S-8, such documents are not being filed with the Securities and
Exchange Commission (the &#147;Commission&#148;) either as part of this registration statement or as
prospectuses or prospectus supplements pursuant to Rule&nbsp;424 under the Securities Act. Rio Vista
Energy Partners L.P. (the &#147;Partnership&#148;) shall maintain a file of such documents in accordance with
the provisions of Rule&nbsp;428(a)(2) of the Securities Act. Upon request, the Partnership shall
furnish to the Commission or its staff a copy of any or all of the documents included in the file.
</DIV>


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<!-- link1 "PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT" -->
<DIV align="left"><A NAME="001"></A></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>PART II</B>
</DIV>

 <DIV align="center" style="font-size: 10pt; margin-top: 6pt"><B>INFORMATION REQUIRED IN THE REGISTRATION STATEMENT</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;3. Incorporation of Documents by Reference.</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Partnership incorporates by reference in this registration statement the following
documents and information previously filed with the Commission:
</DIV>

<DIV style="margin-top: 6pt">
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(1)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The annual report on Form 10-K as filed by the Partnership with the Commission
(File No.&nbsp;000-50394) on April&nbsp;17, 2007.</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(2)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The quarterly reports on Form 10-Q as filed by the Registrant with the
Commission (File No.&nbsp;000-50394) on May&nbsp;21, 2007, August&nbsp;20, 2007, and November&nbsp;19,
2007.</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(3)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The current reports on Form 8-K or 8-K/A as filed by the Registrant with the
Commission (File No.&nbsp;000-50394) on February&nbsp;20, 2007, March&nbsp;9, 2007, March&nbsp;27, 2007, June&nbsp;21, 2007, July&nbsp;6,
2007, August&nbsp;1, 2007, September&nbsp;18, 2007, October&nbsp;26, 2007, November&nbsp;26, 2007, December&nbsp;4,
2007, December&nbsp;10, 2007, January&nbsp;3, 2008, and January&nbsp;29, 2008.</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left">(4)</TD>
    <TD width="1%">&nbsp;</TD>
    <TD>The description of the Partnership&#146;s common units contained in the
Partnership&#146;s Amendment No.&nbsp;1 to Form&nbsp;10 (File No.&nbsp;000-50394) as filed by the
Partnership with the Commission on September&nbsp;16, 2004, and any amendment or report
filed for the purpose of updating that description.</TD>
</TR>

</TABLE>
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;All documents filed with the Commission by the Partnership pursuant to Sections&nbsp;13(a), 13(c),
14 or 15(d) of the Securities Exchange Act of 1934, as amended, (excluding any information
furnished pursuant to Item&nbsp;2.02 and Item&nbsp;7.01 on any current report on Form 8-K) subsequent to the
date of this registration statement and prior to the filing of a post-effective amendment that
indicates that all securities offered have been sold or that deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this registration statement
and to be a part hereof from the date of filing of such documents. Nothing in this item shall be
deemed to incorporate information furnished to, but not filed with, the SEC pursuant to Item&nbsp;2.02
or Item&nbsp;7.01 of Form 8-K (or corresponding information furnished under Item&nbsp;9.01 or included as an
exhibit).
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Any statement contained herein or in a document incorporated or deemed to be incorporated
herein by reference shall be deemed to be modified or superseded for purposes of this registration
statement to the extent that a statement contained herein or in any subsequently filed document
that also is, or is deemed to be, incorporated by reference herein modifies or supersedes such
statement. Any such statement so modified or superseded shall not be deemed, except as so modified
or superseded, to constitute a part of this registration statement.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;4. Description of Securities.</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Not applicable.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;5. Interests of Named Experts and Counsel.</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The legality of the common units offered hereby is being passed upon for us by Andrews Kurth
LLP.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;6. Indemnification of Directors and Officers.</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Under the partnership agreement, in most circumstances, we will indemnify the following
persons, to the fullest extent permitted by law, from and against all losses, claims, damages or
similar events:
</DIV>

<DIV style="margin-top: 6pt">
<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">

<TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left"><B>&#149;</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD>our general partner;</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left"><B>&#149;</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD>any departing general partner;</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left"><B>&#149;</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD>any person who is or was an affiliate of a general partner or any departing general
partner;</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left"><B>&#149;</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD>any person who is or was a member, partner, officer, manager, employee, agent or trustee
of our general partner, any departing general partner, or any affiliate of a general partner
or any departing general partner; or</TD>
</TR>

<TR>
    <TD style="font-size: 6pt">&nbsp;</TD>
</TR><TR valign="top" style="font-size: 10pt; color: #000000; background: transparent">
    <TD width="2%" style="background: transparent">&nbsp;</TD>
    <TD width="3%" nowrap align="left"><B>&#149;</B></TD>
    <TD width="1%">&nbsp;</TD>
    <TD>any person who is or was serving at the request of a general partner or any departing
general partner or any affiliate of a general partner or any departing general partner, as
an officer, director, manager, employee, member, partner, agent or trustee of another
person.</TD>
</TR>

</TABLE>
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Any indemnification under these provisions will only be out of our assets. Our general partner
will not be personally liable for, or have any obligation to contribute or loan funds or assets to
us to enable us to effectuate,
</DIV>

<P align="center" style="font-size: 10pt"><!-- Folio -->II-1<!-- /Folio -->
</DIV>

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<H5 align="left" style="page-break-before:always"><A HREF="#toc">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">



<DIV align="left" style="font-size: 10pt; margin-top: 6pt">indemnification. We may purchase insurance against liabilities asserted against and expenses
incurred by persons for our activities, regardless of whether we would have the power to indemnify
the person against liabilities under the partnership agreement.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Subject to any terms, conditions or restrictions set forth in the partnership agreement,
Section&nbsp;17-108 of the Delaware Revised Uniform Limited Partnership Act empowers a Delaware limited
partnership to indemnify and hold harmless any partner or other person from and against all claims
and demands whatsoever. In addition, we have approved indemnification agreements with managers and
officers of our general partner. The form of this agreement was filed as Exhibit&nbsp;10.25 to our
Annual Report on Form 10-K for the year ended December&nbsp;31, 2006.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">To the extent that the indemnification provisions of our partnership agreement purport to include
indemnification for liabilities arising under the Securities Act of 1933, in the opinion of the
SEC, such indemnification is contrary to public policy and is therefore unenforceable.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;7. Exemption from Registration Claimed.</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Not applicable.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;8. Exhibits.</B>
</DIV>

<DIV align="right">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="97%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="90%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left">Exhibit</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left" style="border-bottom: 1px solid #000000">Number</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="left" style="border-bottom: 1px solid #000000">Description</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certificate of Limited Partnership of Rio Vista Energy Partners
L.P. filed July&nbsp;10, 2003. (Incorporated by reference to Rio
Vista&#146;s registration statement on Form&nbsp;10 filed August&nbsp;26, 2004
and amended Form&nbsp;10 filed on September&nbsp;16, 2004) (SEC File No.
000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.2
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Amendment of Certificate of Limited Partnership of Rio Vista
Energy Partners L.P. filed September&nbsp;17, 2003. (Incorporated by
reference to Rio Vista&#146;s Quarterly Report on Form&nbsp;10-Q for the
quarter ended September&nbsp;30, 2004 filed on November&nbsp;22, 2004, SEC
File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.3
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">First Amended and Restated Limited Partnership Agreement of Rio
Vista Energy Partners L.P. dated September&nbsp;16, 2004.
(Incorporated by reference to Rio Vista&#146;s registration statement
on Form&nbsp;10 filed August&nbsp;26, 2004 and amended Form&nbsp;10 filed on
September&nbsp;16, 2004) (SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.4
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">First Amendment to the First Amended and Restated Agreement of
Limited Partnership of Rio Vista Energy Partners L.P. dated as
of October&nbsp;26, 2005. (Incorporated by reference to Rio Vista&#146;s
Quarterly Report on Form&nbsp;10-Q for the quarter ended September
30, 2005 filed on November&nbsp;21, 2005, SEC File No.&nbsp;000-50394).</TD>
</TR>


<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.5
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certificate of Formation of Rio Vista GP LLC. (Incorporated by reference to Rio
Vista&#146;s registration statement on Form&nbsp;10 filed August&nbsp;26, 2004 and amended Form&nbsp;10
filed on September&nbsp;16, 2004) (SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.6
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Rio Vista GP LLC Amended and Restated Limited Liability Company Agreement dated
as of September&nbsp;16, 2004. (Incorporated by reference to Rio Vista&#146;s registration
statement on Form&nbsp;10 filed August&nbsp;26, 2004 and amended Form&nbsp;10 filed on September&nbsp;16,
2004) (SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.7
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">First Amendment to Amended and Restated Limited Liability Company Agreement of
Rio Vista GP LLC dated October&nbsp;2, 2006. (Incorporated by reference to Rio Vista&#146;s
Annual Report on Form&nbsp;10-K for the year ended December&nbsp;31, 2005 filed on April&nbsp;6, 2006,
SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.8
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Specimen Unit Certificate for Common Units (contained in Exhibit&nbsp;3.2).
(Incorporated by reference to Rio Vista&#146;s registration statement on Form&nbsp;10 filed
August&nbsp;26, 2004 and amended Form&nbsp;10 filed on September&nbsp;16, 2004) (SEC File No.
000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.9
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Rio Vista Energy Partners L.P. 2005 Equity Incentive Plan. (Incorporated by
reference to Rio Vista&#146;s Annual Report on Form&nbsp;10-K for the year ended December&nbsp;31,
2004 filed on April&nbsp;12, 2005, SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.10
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Form of Nonqualified Unit Option Agreement under the 2005 Rio Vista Energy
Partners L.P. Equity Incentive Plan. (Incorporated by reference to Rio Vista&#146;s Annual
Report on Form&nbsp;10-K for the year ended December&nbsp;31, 2006 filed on April&nbsp;17, 2007, SEC
File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*5.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Opinion of Andrews Kurth LLP with respect to legality of the securities.</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*23.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Consent of Consent of Burton McCumber &#038; Cortez, L.L.P.</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*23.4
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Consent of Andrews Kurth LLP (included as part of Exhibit&nbsp;5.1).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*24.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Power of Attorney (set forth on the signature page of this registration statement).</TD>
</TR>
<!-- End Table Body -->
</TABLE>
</DIV>



<DIV align="left">
<DIV style="font-size: 3pt; margin-top: 16pt; width: 18%; border-top: 1px solid #000000">&nbsp;</DIV>
</DIV>

<TABLE width="100%" border="0" cellpadding="0" cellspacing="0" style="font-size: 10pt">
<TR>
    <TD width="3%"></TD>
    <TD width="1%"></TD>
    <TD width="96"></TD>
</TR>

<TR valign="top">
    <TD nowrap align="left">&#043;</TD>
    <TD>&nbsp;</TD>
    <TD>Incorporated by reference.</TD>
</TR>

<TR style="font-size: 3pt"><TD>&nbsp;</TD></TR>

<TR valign="top">
    <TD nowrap align="left">*</TD>
    <TD>&nbsp;</TD>
    <TD>Filed herewith.</TD>
</TR>

</TABLE>



<DIV align="left" style="font-size: 10pt; margin-top: 12pt"><B>Item&nbsp;9. Undertakings.</B>
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">(a)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The undersigned registrant hereby undertakes:
</DIV>


<P align="center" style="font-size: 10pt"><!-- Folio -->II-2<!-- /Folio -->
</DIV>

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<DIV style="font-family: 'Times New Roman',Times,serif">




<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;To file, during any period in which offers or sales are being made, a post-effective
amendment to this registration statement:
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt; margin-left: 2%">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;To include any prospectus required by Section&nbsp;10(a)(3) of the Securities Act of
1933;
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt; margin-left: 2%">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;To reflect in the prospectus any facts or events arising after the effective date
of the registration statement (or the most recent post-effective amendment thereof) which,
individually or in the aggregate, represent a fundamental change in the information set
forth in the registration statement. Notwithstanding the foregoing, any increase or
decrease in volume of securities offered (if the total dollar value of securities offered
would not exceed that which was registered) and any deviation from the low or high end of
the estimated maximum offering range may be reflected in the form of prospectus filed with
the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price
represent no more than a 20% change in the maximum aggregate offering price set forth in the
&#147;Calculation of Registration Fee&#148; table in the effective registration statement;
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt; margin-left: 2%">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;To include any material information with respect to the plan of distribution not
previously disclosed in the registration statement or any material change to such
information in the registration statement;
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt; margin-left: 2%"><I>Provided, however, </I>That paragraphs (a)(1)(i) and (a)(1)(ii) of this section do not apply if
the information required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the Commission by the registrant
pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are
incorporated by reference in the registration statement.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;That, for the purpose of determining any liability under the Securities Act of 1933, each
such post-effective amendment shall be deemed to be a new registration statement relating to the
securities offered therein, and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(3)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;To remove from registration by means of a post-effective amendment any of the securities
being registered which remain unsold at the termination of the offering.
</DIV>
<DIV align="left" style="font-size: 10pt; margin-top: 6pt">(b)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The undersigned registrant hereby undertakes that, for purposes of determining any liability
under the Securities Act of 1933, each filing of the registrant&#146;s annual report pursuant to section
13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing
of an employee benefit plan&#146;s annual report pursuant to section 15(d) of the Securities Exchange
Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be
a new registration statement relating to the securities offered therein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering thereof.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">(c)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be
permitted to directors, officers and controlling persons of the registrant pursuant to the
provisions described under Item&nbsp;6 above, or otherwise, the registrant has been advised that in the
opinion of the Commission such indemnification is against public policy as expressed in the Act and
is, therefore, unenforceable. In the event that a claim for indemnification against such
liabilities (other than the payment of the registrant of expenses incurred or paid by a director,
officer or controlling person of the registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in connection with the
securities being registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate jurisdiction the
question whether such indemnification by it is against public policy as expressed in the Securities
Act of 1933 and will be governed by the final adjudication of such issue.
</DIV>



<P align="center" style="font-size: 10pt"><!-- Folio -->II-3<!-- /Folio -->
</DIV>

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<H5 align="left" style="page-break-before:always"><A HREF="#toc">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">



<!-- link1 "SIGNATURES" -->
<DIV align="left"><A NAME="002"></A></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>SIGNATURES</B>
</DIV>


<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it
has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and
has duly caused this registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of Houston, State of Texas, on February&nbsp;14, 2008.
</DIV>

<TABLE width="100%" border="0" cellspacing="0" cellpadding="0" style="font-size: 10pt">
<TR>
    <TD width="48%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="1%">&nbsp;</TD>
    <TD width="35%">&nbsp;</TD>
    <TD width="15%">&nbsp;</TD>
</TR>
<TR>
    <TD valign="top" align="left">&nbsp;</TD>
    <TD colspan="3" align="left">Rio Vista Energy Partners L.P.<BR>
&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">&nbsp;</TD>
    <TD valign="top">By:&nbsp;&nbsp;</TD>
    <TD colspan="2" align="left">Rio Vista GP LLC, its general partner
&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="2" align="left">&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR>
    <TD align="left">&nbsp;</TD>
    <TD valign="top">By:&nbsp;&nbsp;</TD>
    <TD colspan="2" style="border-bottom: 1px solid #000000" align="left">  /s/ Ian T. Bothwell
&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="2" align="left">Ian T. Bothwell&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR><TR>
    <TD align="left">&nbsp;</TD>
    <TD>&nbsp;</TD>
    <TD colspan="2" align="left">Acting Chief Executive Officer, Acting President,<BR>
Vice President, Chief Financial Officer,<BR>
Treasurer and Assistant Secretary&nbsp;</TD>
    <TD>&nbsp;</TD>
</TR>
<TR>
    <TD colspan="5">&nbsp;</TD>
</TR>
</TABLE>
<!-- link1 "POWER OF ATTORNEY" -->
<DIV align="left"><A NAME="003"></A></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>POWER OF ATTORNEY</B>
</DIV>



<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The undersigned managers and officers of Rio Vista GP LLC, the general partner of Rio Vista
Energy Partners L.P. hereby constitute and appoint Ian T. Bothwell and Douglas G. Manner, each with
full power to act and with full power of substitution and resubstitution, our true and lawful
attorneys-in-fact and agents with full power to execute in our name and behalf in the capacities
indicated below any and all amendments (including post-effective amendments and amendments thereto)
to this registration statement and to file the same, with all exhibits and other documents relating
thereto and any registration statement relating to any offering made pursuant to this registration
statement that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act with
the Securities and Exchange Commission and hereby ratify and confirm all that such attorney-in-fact
or his substitute shall lawfully do or cause to be done by virtue hereof.
</DIV>

<DIV align="left" style="font-size: 10pt; margin-top: 6pt">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Act of 1933, this registration statement has
been signed by the following persons in the capacities and on the date indicated.
</DIV>
<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="40%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="40%">&nbsp;</TD>
    <TD width="3%">&nbsp;</TD>
    <TD width="14%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="center" style="border-bottom: 1px solid #000000">Signature</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" style="border-bottom: 1px solid #000000">Title</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center" style="border-bottom: 1px solid #000000">Date</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom" style="padding-top: 1em">
    <TD align="left" nowrap valign="middle">/s/ Ian T. Bothwell
<DIV style="font-size: 1pt; border-bottom: 1px solid #000000">&nbsp;</DIV>
Ian T. Bothwell</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">
Acting Chief
Executive Officer,
Acting President,
Vice President,
Chief Financial
Officer, Treasurer
and Assistant
Secretary<BR>
(Principal
Executive,
Financial and
Accounting Officer)
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="middle">February 14, 2008</TD>
</TR>
<TR valign="bottom" style="padding-top: 1em">
    <TD align="left" nowrap valign="top">/s/ Richard R. Canney
<DIV style="font-size: 1pt; border-bottom: 1px solid #000000">&nbsp;</DIV>
Richard R. Canney</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">
Manager
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="middle">February 14, 2008</TD>
</TR>
<TR valign="bottom" style="padding-top: 1em">
    <TD align="left" nowrap valign="top">/s/ Murray J. Feiwell
<DIV style="font-size: 1pt; border-bottom: 1px solid #000000">&nbsp;</DIV>
Murray J. Feiwell</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">
Manager
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">February 14, 2008</TD>
</TR>
<TR valign="bottom" style="padding-top: 1em">
    <TD align="left" nowrap valign="top">/s/ Douglas G. Manner
<DIV style="font-size: 1pt; border-bottom: 1px solid #000000">&nbsp;</DIV>
Douglas G. Manner</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">
Manager
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">February 14, 2008</TD>
</TR>
<TR valign="bottom" style="padding-top: 1em">
    <TD align="left" nowrap valign="top">/s/ Bruce I. Raben
<DIV style="font-size: 1pt; border-bottom: 1px solid #000000">&nbsp;</DIV>
Bruce I. Raben</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">
Manager
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">February 14, 2008</TD>
</TR>
<TR valign="bottom" style="padding-top: 1em">
    <TD align="left" nowrap valign="top">/s/ Nicholas J. Singer
<DIV style="font-size: 1pt; border-bottom: 1px solid #000000">&nbsp;</DIV>
Nicholas J. Singer</TD>
    <TD>&nbsp;</TD>
    <TD align="center" valign="top">
Manager
</TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">February 14, 2008</TD>
</TR>
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</DIV>


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<H5 align="left" style="page-break-before:always"><A HREF="#toc">Table of Contents</A></H5><P>

<DIV style="font-family: 'Times New Roman',Times,serif">



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<DIV align="left"><A NAME="004"></A></DIV>

<DIV align="center" style="font-size: 10pt; margin-top: 18pt"><B>EXHIBIT INDEX</B>
</DIV>

<DIV align="center">
<TABLE style="font-size: 10pt" cellspacing="0" border="0" cellpadding="0" width="100%">
<!-- Begin Table Head -->
<TR valign="bottom">
    <TD width="5%">&nbsp;</TD>
    <TD width="5%">&nbsp;</TD>
    <TD width="90%">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left">Exhibit</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="center">&nbsp;</TD>
</TR>
<TR style="font-size: 8pt" valign="bottom">
    <TD nowrap align="left" style="border-bottom: 1px solid #000000">Number</TD>
    <TD>&nbsp;</TD>
    <TD nowrap align="left" style="border-bottom: 1px solid #000000">Description</TD>
</TR>

<!-- End Table Head -->
<!-- Begin Table Body -->
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certificate of Limited Partnership of Rio Vista Energy Partners
L.P. filed July&nbsp;10, 2003. (Incorporated by reference to Rio
Vista&#146;s registration statement on Form&nbsp;10 filed August&nbsp;26, 2004
and amended Form&nbsp;10 filed on September&nbsp;16, 2004) (SEC File No.
000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.2
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Amendment of Certificate of Limited Partnership of Rio Vista
Energy Partners L.P. filed September&nbsp;17, 2003. (Incorporated by
reference to Rio Vista&#146;s Quarterly Report on Form&nbsp;10-Q for the
quarter ended September&nbsp;30, 2004 filed on November&nbsp;22, 2004, SEC
File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.3
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">First Amended and Restated Limited Partnership Agreement of Rio
Vista Energy Partners L.P. dated September&nbsp;16, 2004.
(Incorporated by reference to Rio Vista&#146;s registration statement
on Form&nbsp;10 filed August&nbsp;26, 2004 and amended Form&nbsp;10 filed on
September&nbsp;16, 2004) (SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.4
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">First Amendment to the First Amended and Restated Agreement of
Limited Partnership of Rio Vista Energy Partners L.P. dated as
of October&nbsp;26, 2005. (Incorporated by reference to Rio Vista&#146;s
Quarterly Report on Form&nbsp;10-Q for the quarter ended September
30, 2005 filed on November&nbsp;21, 2005, SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.5
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Certificate of Formation of Rio Vista GP LLC. (Incorporated by reference to Rio
Vista&#146;s registration statement on Form&nbsp;10 filed August&nbsp;26, 2004 and amended Form&nbsp;10
filed on September&nbsp;16, 2004) (SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.6
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Rio Vista GP LLC Amended and Restated Limited Liability Company Agreement dated
as of September&nbsp;16, 2004. (Incorporated by reference to Rio Vista&#146;s registration
statement on Form&nbsp;10 filed August&nbsp;26, 2004 and amended Form&nbsp;10 filed on September&nbsp;16,
2004) (SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.7
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">First Amendment to Amended and Restated Limited Liability Company Agreement of
Rio Vista GP LLC dated October&nbsp;2, 2006. (Incorporated by reference to Rio Vista&#146;s
Annual Report on Form&nbsp;10-K for the year ended December&nbsp;31, 2005 filed on April&nbsp;6, 2006,
SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.8
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Specimen Unit Certificate for Common Units (contained in Exhibit&nbsp;3.2).
(Incorporated by reference to Rio Vista&#146;s registration statement on Form&nbsp;10 filed
August&nbsp;26, 2004 and amended Form&nbsp;10 filed on September&nbsp;16, 2004) (SEC File No.
000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.9
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Rio Vista Energy Partners L.P. 2005 Equity Incentive Plan. (Incorporated by
reference to Rio Vista&#146;s Annual Report on Form&nbsp;10-K for the year ended December&nbsp;31,
2004 filed on April&nbsp;12, 2005, SEC File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&#043;4.10
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Form of Nonqualified Unit Option Agreement under the 2005 Rio Vista Energy
Partners L.P. Equity Incentive Plan. (Incorporated by reference to Rio Vista&#146;s Annual
Report on Form&nbsp;10-K for the year ended December&nbsp;31, 2006 filed on April&nbsp;17, 2007, SEC
File No.&nbsp;000-50394).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*5.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Opinion of Andrews Kurth LLP with respect to legality of the securities.</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*23.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Consent of Consent of Burton McCumber &#038; Cortez, L.L.P.</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*23.4
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Consent of Andrews Kurth LLP (included as part of Exhibit&nbsp;5.1).</TD>
</TR>
<TR valign="bottom"><!-- Blank Space -->
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">&nbsp;</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">&nbsp;</TD>
</TR>
<TR valign="bottom">
    <TD valign="top"><DIV style="margin-left:0px; text-indent:-0px">*24.1
</DIV></TD>
    <TD>&nbsp;</TD>
    <TD align="left" valign="top">Power of Attorney (set forth on the signature page of this registration statement).</TD>
</TR>
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<DIV style="font-size: 3pt; margin-top: 16pt; width: 18%; border-top: 1px solid #000000">&nbsp;</DIV>
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    <TD width="3%"></TD>
    <TD width="1%"></TD>
    <TD width="96"></TD>
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<TR valign="top">
    <TD nowrap align="left">&#043;</TD>
    <TD>&nbsp;</TD>
    <TD>Incorporated by reference.</TD>
</TR>

<TR style="font-size: 3pt"><TD>&nbsp;</TD></TR>

<TR valign="top">
    <TD nowrap align="left">*</TD>
    <TD>&nbsp;</TD>
    <TD>Filed herewith.</TD>
</TR>


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</BODY>
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Rio Vista Energy Partners L.P.
Table of Contents
As filed with the Securities and Exchange Commission on February 14, 2008
Registration No. 333-
UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM S-8
REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933
Rio Vista Energy Partners L.P.
(Exact name of registrant as specified in its charter)
Delaware
20-0153267
(State or other jurisdiction
(I.R.S. Employer
of incorporation or organization)
Identification No.)
1313 Alton Gloor Blvd., Suite J
Brownsville, Texas
98526
(Address of Principal Executive Offices)
(Zip Code)
Rio Vista Energy Partners L.P. 2005 Equity Incentive Plan
(Full title of the plan)
Ian T. Bothwell
Acting Chief Executive Officer
Rio Vista Energy Partners L.P.
1313 Alton Gloor Blvd., Suite J
Brownsville, Texas 98526
(Name and address of agent for service)
(956) 831-0886
(Telephone number, including area code, of agent for service)
Copies to:
Roy E. Bertolatus
Andrews Kurth LLP
600 Travis, Suite 4200
Houston, Texas 77002
(713) 220-4200
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or
a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule
12b-2 of the Exchange Act. (Check one):
Large accelerated filer
o
Accelerated filer
o
Non-accelerated filer
o
Smaller reporting company
x
(Do not check if a smaller reporting company)
CALCULATION OF REGISTRATION FEE
Proposed
maximum
Proposed maximum
aggregate
Amount of
Title of securities
Amount to be
offering price
offering
registration
to be registered
registered (1)(2)
per share (3)
price
fee
Common units representing limited partner interests
750,000 common units
$14.42
$10,815,000.00
$425.03
(1)
Pursuant to Rule 416(a) under the Securities Act, there is also being registered such
additional number of common units that become available under the plan because of events such
as recapitalizations, stock dividends, stock splits or similar transactions effected without
the receipt of consideration that increases the number of outstanding common units.
(2)
Represents common units reserved for issuance under the Rio Vista Energy Partners L.P. 2005
Equity Incentive Plan.
(3)
Estimated solely for the purpose of determining the amount of the registration fee in
accordance with Rule 457(c) and (h) under the Securities Act of 1933, as amended, and based on
the average of the high and low prices of the common units as reported by the NASDAQ Global
Market on February 7, 2008.
TABLE OF CONTENTS
PART I INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
PART II INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
SIGNATURES
POWER OF ATTORNEY
EXHIBIT INDEX
EXHIBIT 5.1
EXHIBIT 23.1
Table of Contents
PART I
INFORMATION REQUIRED IN THE SECTION 10(a) PROSPECTUS
The document(s) containing the information specified in Part I of Form S-8 (plan information
and registrant information) will be sent or given to employees as specified by Rule 428(b)(1) under
the Securities Act of 1933, as amended (the "Securities Act"). In accordance with Rule 428 and the
requirements of Part I of Form S-8, such documents are not being filed with the Securities and
Exchange Commission (the "Commission") either as part of this registration statement or as
prospectuses or prospectus supplements pursuant to Rule 424 under the Securities Act. Rio Vista
Energy Partners L.P. (the "Partnership") shall maintain a file of such documents in accordance with
the provisions of Rule 428(a)(2) of the Securities Act. Upon request, the Partnership shall
furnish to the Commission or its staff a copy of any or all of the documents included in the file.
Table of Contents
PART II
INFORMATION REQUIRED IN THE REGISTRATION STATEMENT
Item 3. Incorporation of Documents by Reference.
The Partnership incorporates by reference in this registration statement the following
documents and information previously filed with the Commission:
(1)
The annual report on Form 10-K as filed by the Partnership with the Commission
(File No. 000-50394) on April 17, 2007.
(2)
The quarterly reports on Form 10-Q as filed by the Registrant with the
Commission (File No. 000-50394) on May 21, 2007, August 20, 2007, and November 19,
2007.
(3)
The current reports on Form 8-K or 8-K/A as filed by the Registrant with the
Commission (File No. 000-50394) on February 20, 2007, March 9, 2007, March 27, 2007, June 21, 2007, July 6,
2007, August 1, 2007, September 18, 2007, October 26, 2007, November 26, 2007, December 4,
2007, December 10, 2007, January 3, 2008, and January 29, 2008.
(4)
The description of the Partnership's common units contained in the
Partnership's Amendment No. 1 to Form 10 (File No. 000-50394) as filed by the
Partnership with the Commission on September 16, 2004, and any amendment or report
filed for the purpose of updating that description.
All documents filed with the Commission by the Partnership pursuant to Sections 13(a), 13(c),
14 or 15(d) of the Securities Exchange Act of 1934, as amended, (excluding any information
furnished pursuant to Item 2.02 and Item 7.01 on any current report on Form 8-K) subsequent to the
date of this registration statement and prior to the filing of a post-effective amendment that
indicates that all securities offered have been sold or that deregisters all securities then
remaining unsold, shall be deemed to be incorporated by reference in this registration statement
and to be a part hereof from the date of filing of such documents. Nothing in this item shall be
deemed to incorporate information furnished to, but not filed with, the SEC pursuant to Item 2.02
or Item 7.01 of Form 8-K (or corresponding information furnished under Item 9.01 or included as an
exhibit).
Any statement contained herein or in a document incorporated or deemed to be incorporated
herein by reference shall be deemed to be modified or superseded for purposes of this registration
statement to the extent that a statement contained herein or in any subsequently filed document
that also is, or is deemed to be, incorporated by reference herein modifies or supersedes such
statement. Any such statement so modified or superseded shall not be deemed, except as so modified
or superseded, to constitute a part of this registration statement.
Item 4. Description of Securities.
Not applicable.
Item 5. Interests of Named Experts and Counsel.
The legality of the common units offered hereby is being passed upon for us by Andrews Kurth
LLP.
Item 6. Indemnification of Directors and Officers.
Under the partnership agreement, in most circumstances, we will indemnify the following
persons, to the fullest extent permitted by law, from and against all losses, claims, damages or
similar events:
•
our general partner;
•
any departing general partner;
•
any person who is or was an affiliate of a general partner or any departing general
partner;
•
any person who is or was a member, partner, officer, manager, employee, agent or trustee
of our general partner, any departing general partner, or any affiliate of a general partner
or any departing general partner; or
•
any person who is or was serving at the request of a general partner or any departing
general partner or any affiliate of a general partner or any departing general partner, as
an officer, director, manager, employee, member, partner, agent or trustee of another
person.
Any indemnification under these provisions will only be out of our assets. Our general partner
will not be personally liable for, or have any obligation to contribute or loan funds or assets to
us to enable us to effectuate,
II-1
Table of Contents
indemnification. We may purchase insurance against liabilities asserted against and expenses
incurred by persons for our activities, regardless of whether we would have the power to indemnify
the person against liabilities under the partnership agreement.
Subject to any terms, conditions or restrictions set forth in the partnership agreement,
Section 17-108 of the Delaware Revised Uniform Limited Partnership Act empowers a Delaware limited
partnership to indemnify and hold harmless any partner or other person from and against all claims
and demands whatsoever. In addition, we have approved indemnification agreements with managers and
officers of our general partner. The form of this agreement was filed as Exhibit 10.25 to our
Annual Report on Form 10-K for the year ended December 31, 2006.
To the extent that the indemnification provisions of our partnership agreement purport to include
indemnification for liabilities arising under the Securities Act of 1933, in the opinion of the
SEC, such indemnification is contrary to public policy and is therefore unenforceable.
Item 7. Exemption from Registration Claimed.
Not applicable.
Item 8. Exhibits.
Exhibit
Number
Description
+4.1
Certificate of Limited Partnership of Rio Vista Energy Partners
L.P. filed July 10, 2003. (Incorporated by reference to Rio
Vista's registration statement on Form 10 filed August 26, 2004
and amended Form 10 filed on September 16, 2004) (SEC File No.
000-50394).
+4.2
Amendment of Certificate of Limited Partnership of Rio Vista
Energy Partners L.P. filed September 17, 2003. (Incorporated by
reference to Rio Vista's Quarterly Report on Form 10-Q for the
quarter ended September 30, 2004 filed on November 22, 2004, SEC
File No. 000-50394).
+4.3
First Amended and Restated Limited Partnership Agreement of Rio
Vista Energy Partners L.P. dated September 16, 2004.
(Incorporated by reference to Rio Vista's registration statement
on Form 10 filed August 26, 2004 and amended Form 10 filed on
September 16, 2004) (SEC File No. 000-50394).
+4.4
First Amendment to the First Amended and Restated Agreement of
Limited Partnership of Rio Vista Energy Partners L.P. dated as
of October 26, 2005. (Incorporated by reference to Rio Vista's
Quarterly Report on Form 10-Q for the quarter ended September
30, 2005 filed on November 21, 2005, SEC File No. 000-50394).
+4.5
Certificate of Formation of Rio Vista GP LLC. (Incorporated by reference to Rio
Vista's registration statement on Form 10 filed August 26, 2004 and amended Form 10
filed on September 16, 2004) (SEC File No. 000-50394).
+4.6
Rio Vista GP LLC Amended and Restated Limited Liability Company Agreement dated
as of September 16, 2004. (Incorporated by reference to Rio Vista's registration
statement on Form 10 filed August 26, 2004 and amended Form 10 filed on September 16,
2004) (SEC File No. 000-50394).
+4.7
First Amendment to Amended and Restated Limited Liability Company Agreement of
Rio Vista GP LLC dated October 2, 2006. (Incorporated by reference to Rio Vista's
Annual Report on Form 10-K for the year ended December 31, 2005 filed on April 6, 2006,
SEC File No. 000-50394).
+4.8
Specimen Unit Certificate for Common Units (contained in Exhibit 3.2).
(Incorporated by reference to Rio Vista's registration statement on Form 10 filed
August 26, 2004 and amended Form 10 filed on September 16, 2004) (SEC File No.
000-50394).
+4.9
Rio Vista Energy Partners L.P. 2005 Equity Incentive Plan. (Incorporated by
reference to Rio Vista's Annual Report on Form 10-K for the year ended December 31,
2004 filed on April 12, 2005, SEC File No. 000-50394).
+4.10
Form of Nonqualified Unit Option Agreement under the 2005 Rio Vista Energy
Partners L.P. Equity Incentive Plan. (Incorporated by reference to Rio Vista's Annual
Report on Form 10-K for the year ended December 31, 2006 filed on April 17, 2007, SEC
File No. 000-50394).
*5.1
Opinion of Andrews Kurth LLP with respect to legality of the securities.
*23.1
Consent of Consent of Burton McCumber & Cortez, L.L.P.
*23.4
Consent of Andrews Kurth LLP (included as part of Exhibit 5.1).
*24.1
Power of Attorney (set forth on the signature page of this registration statement).
+
Incorporated by reference.
*
Filed herewith.
Item 9. Undertakings.
(a)     The undersigned registrant hereby undertakes:
II-2
Table of Contents
(1)     To file, during any period in which offers or sales are being made, a post-effective
amendment to this registration statement:
(i)     To include any prospectus required by Section 10(a)(3) of the Securities Act of
1933;
(ii)     To reflect in the prospectus any facts or events arising after the effective date
of the registration statement (or the most recent post-effective amendment thereof) which,
individually or in the aggregate, represent a fundamental change in the information set
forth in the registration statement. Notwithstanding the foregoing, any increase or
decrease in volume of securities offered (if the total dollar value of securities offered
would not exceed that which was registered) and any deviation from the low or high end of
the estimated maximum offering range may be reflected in the form of prospectus filed with
the Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price
represent no more than a 20% change in the maximum aggregate offering price set forth in the
"Calculation of Registration Fee" table in the effective registration statement;
(iii)     To include any material information with respect to the plan of distribution not
previously disclosed in the registration statement or any material change to such
information in the registration statement;
Provided, however,
That paragraphs (a)(1)(i) and (a)(1)(ii) of this section do not apply if
the information required to be included in a post-effective amendment by those paragraphs is
contained in periodic reports filed with or furnished to the Commission by the registrant
pursuant to section 13 or section 15(d) of the Securities Exchange Act of 1934 that are
incorporated by reference in the registration statement.
(2)     That, for the purpose of determining any liability under the Securities Act of 1933, each
such post-effective amendment shall be deemed to be a new registration statement relating to the
securities offered therein, and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.
(3)     To remove from registration by means of a post-effective amendment any of the securities
being registered which remain unsold at the termination of the offering.
(b)     The undersigned registrant hereby undertakes that, for purposes of determining any liability
under the Securities Act of 1933, each filing of the registrant's annual report pursuant to section
13(a) or section 15(d) of the Securities Exchange Act of 1934 (and, where applicable, each filing
of an employee benefit plan's annual report pursuant to section 15(d) of the Securities Exchange
Act of 1934) that is incorporated by reference in the registration statement shall be deemed to be
a new registration statement relating to the securities offered therein, and the offering of such
securities at that time shall be deemed to be the initial bona fide offering thereof.
(c)     Insofar as indemnification for liabilities arising under the Securities Act of 1933 may be
permitted to directors, officers and controlling persons of the registrant pursuant to the
provisions described under Item 6 above, or otherwise, the registrant has been advised that in the
opinion of the Commission such indemnification is against public policy as expressed in the Act and
is, therefore, unenforceable. In the event that a claim for indemnification against such
liabilities (other than the payment of the registrant of expenses incurred or paid by a director,
officer or controlling person of the registrant in the successful defense of any action, suit or
proceeding) is asserted by such director, officer or controlling person in connection with the
securities being registered, the registrant will, unless in the opinion of its counsel the matter
has been settled by controlling precedent, submit to a court of appropriate jurisdiction the
question whether such indemnification by it is against public policy as expressed in the Securities
Act of 1933 and will be governed by the final adjudication of such issue.
II-3
Table of Contents
SIGNATURES
Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it
has reasonable grounds to believe that it meets all of the requirements for filing on Form S-8 and
has duly caused this registration statement to be signed on its behalf by the undersigned,
thereunto duly authorized, in the City of Houston, State of Texas, on February 14, 2008.
Rio Vista Energy Partners L.P.
By:
Rio Vista GP LLC, its general partner
By:
/s/ Ian T. Bothwell
Ian T. Bothwell
Acting Chief Executive Officer, Acting President,
Vice President, Chief Financial Officer,
Treasurer and Assistant Secretary
POWER OF ATTORNEY
The undersigned managers and officers of Rio Vista GP LLC, the general partner of Rio Vista
Energy Partners L.P. hereby constitute and appoint Ian T. Bothwell and Douglas G. Manner, each with
full power to act and with full power of substitution and resubstitution, our true and lawful
attorneys-in-fact and agents with full power to execute in our name and behalf in the capacities
indicated below any and all amendments (including post-effective amendments and amendments thereto)
to this registration statement and to file the same, with all exhibits and other documents relating
thereto and any registration statement relating to any offering made pursuant to this registration
statement that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act with
the Securities and Exchange Commission and hereby ratify and confirm all that such attorney-in-fact
or his substitute shall lawfully do or cause to be done by virtue hereof.
Pursuant to the requirements of the Securities Act of 1933, this registration statement has
been signed by the following persons in the capacities and on the date indicated.
Signature
Title
Date
/s/ Ian T. Bothwell
Ian T. Bothwell
Acting Chief
Executive Officer,
Acting President,
Vice President,
Chief Financial
Officer, Treasurer
and Assistant
Secretary
(Principal
Executive,
Financial and
Accounting Officer)
February 14, 2008
/s/ Richard R. Canney
Richard R. Canney
Manager
February 14, 2008
/s/ Murray J. Feiwell
Murray J. Feiwell
Manager
February 14, 2008
/s/ Douglas G. Manner
Douglas G. Manner
Manager
February 14, 2008
/s/ Bruce I. Raben
Bruce I. Raben
Manager
February 14, 2008
/s/ Nicholas J. Singer
Nicholas J. Singer
Manager
February 14, 2008
Table of Contents
EXHIBIT INDEX
Exhibit
Number
Description
+4.1
Certificate of Limited Partnership of Rio Vista Energy Partners
L.P. filed July 10, 2003. (Incorporated by reference to Rio
Vista's registration statement on Form 10 filed August 26, 2004
and amended Form 10 filed on September 16, 2004) (SEC File No.
000-50394).
+4.2
Amendment of Certificate of Limited Partnership of Rio Vista
Energy Partners L.P. filed September 17, 2003. (Incorporated by
reference to Rio Vista's Quarterly Report on Form 10-Q for the
quarter ended September 30, 2004 filed on November 22, 2004, SEC
File No. 000-50394).
+4.3
First Amended and Restated Limited Partnership Agreement of Rio
Vista Energy Partners L.P. dated September 16, 2004.
(Incorporated by reference to Rio Vista's registration statement
on Form 10 filed August 26, 2004 and amended Form 10 filed on
September 16, 2004) (SEC File No. 000-50394).
+4.4
First Amendment to the First Amended and Restated Agreement of
Limited Partnership of Rio Vista Energy Partners L.P. dated as
of October 26, 2005. (Incorporated by reference to Rio Vista's
Quarterly Report on Form 10-Q for the quarter ended September
30, 2005 filed on November 21, 2005, SEC File No. 000-50394).
+4.5
Certificate of Formation of Rio Vista GP LLC. (Incorporated by reference to Rio
Vista's registration statement on Form 10 filed August 26, 2004 and amended Form 10
filed on September 16, 2004) (SEC File No. 000-50394).
+4.6
Rio Vista GP LLC Amended and Restated Limited Liability Company Agreement dated
as of September 16, 2004. (Incorporated by reference to Rio Vista's registration
statement on Form 10 filed August 26, 2004 and amended Form 10 filed on September 16,
2004) (SEC File No. 000-50394).
+4.7
First Amendment to Amended and Restated Limited Liability Company Agreement of
Rio Vista GP LLC dated October 2, 2006. (Incorporated by reference to Rio Vista's
Annual Report on Form 10-K for the year ended December 31, 2005 filed on April 6, 2006,
SEC File No. 000-50394).
+4.8
Specimen Unit Certificate for Common Units (contained in Exhibit 3.2).
(Incorporated by reference to Rio Vista's registration statement on Form 10 filed
August 26, 2004 and amended Form 10 filed on September 16, 2004) (SEC File No.
000-50394).
+4.9
Rio Vista Energy Partners L.P. 2005 Equity Incentive Plan. (Incorporated by
reference to Rio Vista's Annual Report on Form 10-K for the year ended December 31,
2004 filed on April 12, 2005, SEC File No. 000-50394).
+4.10
Form of Nonqualified Unit Option Agreement under the 2005 Rio Vista Energy
Partners L.P. Equity Incentive Plan. (Incorporated by reference to Rio Vista's Annual
Report on Form 10-K for the year ended December 31, 2006 filed on April 17, 2007, SEC
File No. 000-50394).
*5.1
Opinion of Andrews Kurth LLP with respect to legality of the securities.
*23.1
Consent of Consent of Burton McCumber & Cortez, L.L.P.
*23.4
Consent of Andrews Kurth LLP (included as part of Exhibit 5.1).
*24.1
Power of Attorney (set forth on the signature page of this registration statement).
+
Incorporated by reference.
*
Filed herewith.