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<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;border-bottom:solid 2.25pt;padding-bottom:1;padding-top:0;'><font size=5>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font SIZE=5>UNITED STATES</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font SIZE=5>SECURITIES AND EXCHANGE COMMISSION</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>Washington, D.C. 20549</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>___________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font SIZE=5>FORM 8-K</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font SIZE=2>CURRENT REPORT</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>PURSUANT TO SECTION 13 OR 15(d) OF THE</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font SIZE=2>SECURITIES EXCHANGE ACT OF 1934</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>Date of Report (Date of earliest event reported) May 24, 2006</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font SIZE=5>BLACK HILLS CORPORATION</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=2>(Exact name of registrant as specified in its charter)</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=3>&nbsp;</font></p>


<table border="0" cellspacing=0 cellpadding=0 width="93%" style='margin-left:23.4pt;border-collapse:collapse'>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>South Dakota</font></b><b></b></p> </td> </tr>
    <tr >
        <td  colspan="4" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(State or other jurisdiction of incorporation)</font></b><b></b></p> </td> </tr>
    <tr >
        <td width="27%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>001-31303</font></b><b></b></p> </td>
        <td width="39%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>46-0458824</font></b><b></b></p> </td> </tr>
    <tr >
        <td width="27%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Commission File Number)</font></b><b></b></p> </td>
        <td width="39%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(IRS Employer Identification No.)</font></b><b></b></p> </td> </tr>
    <tr >
        <td width="27%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td>
        <td width="39%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td> </tr>
    <tr >
        <td  colspan="2" rowspan=2 valign=top style=' padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>625 Ninth Street, PO Box 1400 </font></b></p>
<p style='margin-left:12.6pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Rapid City, South Dakota</font></b></p>
<p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Address of principal executive offices)</font></b><b></b></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>57709-1400</font></b><b></b></p> </td> </tr>
    <tr >
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Zip Code)</font></b><b></b></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>605.721.1700</font></b><b></b></p> </td> </tr>
    <tr >
        <td  colspan="4" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Registrant&#146;s telephone number, including area code)</font></b><b></b></p> </td> </tr>
    <tr >
        <td width="27%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td>
        <td  colspan="2" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td>
        <td width="31%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b>&nbsp;</b></p> </td> </tr>
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        <td  colspan="4" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>Not Applicable</font></b><b></b></p> </td> </tr>
    <tr >
        <td  colspan="4" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:center;margin-top:0pt;margin-bottom:0pt'><b><font size=2>(Former name or former address, if changed since last report)</font></b><b></b></p> </td> </tr>
    <tr>
        <td width="190" ></td>

        <td width="274" ></td>

        <td width="14" ></td>

        <td width="218" ></td> </tr> </table>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><b><font size=3>____________</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt; text-indent:0.5in;text-align:left;'><font size=2>Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (</font><i><font size=2>see</font></i><font size=2> General Instruction A.2. below):</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt; text-indent:0.5in;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>&#144;</font></b><b></b></p> </td>
        <td width="97%" style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)</font></p>
<p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>&#144;</font></b><b></b></p> </td>
        <td width="97%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)</font></p>
<p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>&#144;</font></b><b></b></p> </td>
        <td width="97%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))</font></p>
<p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><b><font size=2>&#144;</font></b><b></b></p> </td>
        <td width="97%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))</font></p> </td> </tr></table>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;border-bottom:solid 2.25pt;padding-bottom:1;padding-top:0;'><font size=2>&nbsp;</font></p>


<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>1</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style='page-break-before:always'></p>
<pAGE>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><b><font size=2>Item 1.01 Entry into a Material Definitive Agreement</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:12pt; margin-top:0pt;text-align:left;'><font size=2>On May 24, 2006, the Registrant (the &#147;Guarantor&#148;) entered into an Amended and Restated Guaranty dated as of May 24, 2006, in favor of Wygen Funding, Limited Partnership (&#147;Lessor&#148;).    </font></p>

<p style=' margin-bottom:12pt; margin-top:0pt;text-align:left;'><font size=2>Under the terms of the original Guarantee, the Registrant guaranteed the obligations of the Registrant&#146;s subsidiary, Black Hills Wyoming, Inc. (the &#147;Lessee&#148;), pursuant to the Lease Agreement for the Wygen I plant with Wygen Funding (the &#147;Lessor&#148;) dated as of July 20, 2001, which was filed as Exhibit 10.33 to the Registrant&#146;s Form 10-K for 2001, and is incorporated herein by reference.  Wygen Funding is considered a variable interest entity and the Lessee is considered the primary beneficiary, therefore the variable interest entity has been consolidated by the Registrant in its consolidated financial statements since 2003.  Approximately $128 million of Lessor debt is currently included in the Registrant&#146;s consolidated balance sheet, which is comprised of $111.1 million of Tranche A debt due June 30, 2006 and $17.2 million of Tranche B debt due June 30, 2008.  The maturity of
the Tranche A debt has been extended from June 30, 2006 to June 30, 2008.</font></p>

<p style=' margin-bottom:12pt; margin-top:0pt;text-align:left;'><font size=2>The Amended and Restated Guarantee amends the financial covenants to conform them to the financial covenants in the Registrant&#146;s existing revolving credit facility and to include the extension of Tranche A debt under the guarantee.  </font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><b><font size=2>Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant</font></b></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>The information required by this item is included in Item 1.01.</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'>
</p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>2</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style='page-break-before:always'></p>
<pAGE>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><u><font SIZE=2>SIGNATURES</font></u></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt; text-indent:0.54in;text-align:left;'><font size=2>Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font SIZE=2>BLACK HILLS CORPORATION</font></p> </td> </tr>
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        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>By:&nbsp;&nbsp;</font><u><font size=2>/s/ Mark T. Thies</font></u>                                                                                                                   </p> </td> </tr>
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        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:21.0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Mark T. Thies</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:21.75pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Executive Vice President</font></p> </td> </tr>
    <tr >
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:26.25pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>and Chief Financial Officer</font></p> </td> </tr>
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        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr>
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            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=2>Date:&nbsp;&nbsp;May 30, 2006</font></p> </td>
        <td width="50%" valign=top style='padding:0in 5.4pt 0in 5.4pt'>
            <p style='margin-left:0pt;text-indent:0pt;text-align:left;margin-top:0pt;margin-bottom:0pt'><font size=1>&nbsp;</font></p> </td> </tr></table>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:center;'><font size=2>3</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>

<p style=' margin-bottom:0pt; margin-top:0pt;text-align:left;'><font size=2>&nbsp;</font></p>


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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
___________
FORM 8-K
____________
CURRENT REPORT
PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934
Date of Report (Date of earliest event reported) May 24, 2006
____________
BLACK HILLS CORPORATION
(Exact name of registrant as specified in its charter)
____________
South Dakota
(State or other jurisdiction of incorporation)
001-31303
46-0458824
(Commission File Number)
(IRS Employer Identification No.)
625 Ninth Street, PO Box 1400
Rapid City, South Dakota
(Address of principal executive offices)
57709-1400
(Zip Code)
605.721.1700
(Registrant's telephone number, including area code)
Not Applicable
(Former name or former address, if changed since last report)
____________
Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (
see
General Instruction A.2. below):

Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))
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Item 1.01 Entry into a Material Definitive Agreement
On May 24, 2006, the Registrant (the "Guarantor") entered into an Amended and Restated Guaranty dated as of May 24, 2006, in favor of Wygen Funding, Limited Partnership ("Lessor").
Under the terms of the original Guarantee, the Registrant guaranteed the obligations of the Registrant's subsidiary, Black Hills Wyoming, Inc. (the "Lessee"), pursuant to the Lease Agreement for the Wygen I plant with Wygen Funding (the "Lessor") dated as of July 20, 2001, which was filed as Exhibit 10.33 to the Registrant's Form 10-K for 2001, and is incorporated herein by reference.  Wygen Funding is considered a variable interest entity and the Lessee is considered the primary beneficiary, therefore the variable interest entity has been consolidated by the Registrant in its consolidated financial statements since 2003.  Approximately $128 million of Lessor debt is currently included in the Registrant's consolidated balance sheet, which is comprised of $111.1 million of Tranche A debt due June 30, 2006 and $17.2 million of Tranche B debt due June 30, 2008.  The maturity of
the Tranche A debt has been extended from June 30, 2006 to June 30, 2008.
The Amended and Restated Guarantee amends the financial covenants to conform them to the financial covenants in the Registrant's existing revolving credit facility and to include the extension of Tranche A debt under the guarantee.
Item 2.03 Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant
The information required by this item is included in Item 1.01.
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SIGNATURES
Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.
BLACK HILLS CORPORATION
By:
/s/ Mark T. Thies
Mark T. Thies
Executive Vice President
and Chief Financial Officer
Date:  May 30, 2006
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